*** empty log message ***
[bpt/emacs.git] / etc / NEWS
1 GNU Emacs NEWS -- history of user-visible changes. 2001-03-15
2 Copyright (C) 1999, 2000, 2001, 2002 Free Software Foundation, Inc.
3 See the end for copying conditions.
4
5 Please send Emacs bug reports to bug-gnu-emacs@gnu.org.
6 For older news, see the file ONEWS
7
8 Temporary note:
9 +++ indicates that the appropriate manual has already been updated.
10 --- means no change in the manuals is called for.
11 When you add a new item, please add it without either +++ or ---
12 so we will look at it
13
14 \f
15 * Installation Changes in Emacs 21.3
16
17 ** Emacs now supports new configure options `--program-prefix',
18 `--program-suffix' and `--program-transform-name' that affect the names of
19 installed programs.
20
21 ---
22 ** Leim is now part of the Emacs distribution.
23 You no longer need to download a separate tarball in order to build
24 Emacs with Leim.
25
26 ---
27 ** Support for FreeBSD/Alpha has been added.
28
29 ---
30 ** Support for BSD/OS 5.0 was added.
31
32 \f
33 * Changes in Emacs 21.3
34
35 ** On X and MS Windows, the blinking cursor's "off" state is now shown
36 as a hollow box or a thin bar.
37
38 +++
39 ** Emacs now supports ICCCM Extended Segments in X selections.
40
41 Some versions of X, notably XFree86, use Extended Segments to encode
42 in X selections characters that belong to character sets which are not
43 part of the list of standard charsets supported by the ICCCM spec.
44 Examples of such non-standard character sets include ISO 8859-14, ISO
45 8859-15, KOI8-R, and BIG5. The new coding system
46 `compound-text-with-extensions' supports these extensions, and is now
47 used by default for encoding and decoding X selections. If you don't
48 want this support, set `selection-coding-system' to `compound-text'.
49
50 +++
51 ** The parameters of automatic hscrolling can now be customized.
52 The variable `hscroll-margin' determines how many columns away from
53 the window edge point is allowed to get before automatic hscrolling
54 will horizontally scroll the window. The default value is 5.
55
56 The variable `hscroll-step' determines how many columns automatic
57 hscrolling will scroll the window when point gets too close to the
58 window edge. If its value is zero, the default, Emacs scrolls the
59 window so as to center point. If its value is an integer, it says how
60 many columns to scroll. If the value is a floating-point number, it
61 gives the fraction of the window's width to scroll the window.
62
63 +++
64 ** The variable `automatic-hscrolling' was renamed to `auto-hscroll-mode'.
65 The old name is still available as an alias.
66
67 ** New display feature: focus follows mouse. If you set the variable
68 x-autoselect-window to non-nil value, moving the mouse to a different
69 Emacs window will select that window. The default is nil, so that
70 this feature is not enabled.
71
72 ** The new command `describe-text-at' pops up a buffer with description
73 of text properties, overlays, and widgets at point, and lets you get
74 more information about them, by clicking on mouse-sensitive areas or
75 moving there and pressing RET.
76
77 ** Emacs normally highlights mouse sensitive text whenever the mouse
78 is over the text. By setting the new variable `mouse-highlight', you
79 can optionally enable mouse highlighting only after you move the
80 mouse, so that highlighting disappears when you press a key. You can
81 also disable mouse highlighting.
82
83 ** font-lock: in modes like C and Lisp where the fontification assumes that
84 an open-paren in column 0 is always outside of any string or comment,
85 font-lock now highlights any such open-paren-in-column-zero in bold-red
86 if it is inside a string or a comment, to indicate that it can cause
87 trouble with fontification and/or indentation.
88
89 +++
90 ** There's a new face `minibuffer-prompt'.
91 Emacs adds this face to the list of text properties stored in the
92 variable `minibuffer-prompt-properties', which is used to display the
93 prompt string.
94
95 +++
96 ** The new face `mode-line-inactive' is used to display the mode line
97 of non-selected windows. The `mode-line' face is now used to display
98 the mode line of the currently selected window.
99
100 The new variable `mode-line-in-non-selected-windows' controls whether
101 the `mode-line-inactive' face is used.
102
103 ** A menu item "Show/Hide" was added to the top-level menu "Options".
104 This menu allows you to turn various display features on and off (like
105 tool bar and the menu bar itself). You can also move the vertical
106 scroll bar to either side here or turn it off completely. There is also
107 a menu-item to toggle displaying of current date and time, current line
108 and column number in the mode-line.
109
110 ** Speedbar has moved from the "Tools" top level menu to "Show/Hide".
111
112 ** Emacs can now indicate in the mode-line the presence of new e-mails in
113 directory in addition to file. See the documentation of the user option
114 `display-time-mail-directory'.
115
116 +++
117 ** The new option `Info-scroll-prefer-subnodes' causes Info to behave
118 like the stand-alone Info reader (from the GNU Texinfo package) as far
119 as motion between nodes and their subnodes is concerned. If it is t
120 (the default), Emacs behaves as before when you type SPC in a menu: it
121 visits the subnode pointed to by the first menu entry. If this option
122 is nil, SPC scrolls to the end of the current node, and only then goes
123 to the first menu item, like the stand-alone reader does.
124
125 This change was already in Emacs 21.1, but wasn't advertised in the
126 NEWS.
127
128 ---
129 ** LDAP support now defaults to ldapsearch from OpenLDAP version 2.
130
131 +++
132 ** You can now disable pc-selection-mode after enabling it.
133 M-x pc-selection-mode behaves like a proper minor mode, and with no
134 argument it toggles the mode.
135
136 Turning off PC-Selection mode restores the global key bindings
137 that were replaced by turning on the mode.
138
139 ** Changes in support of colors on character terminals
140
141 +++
142 *** The new command-line option --color=MODE lets you specify a standard
143 mode for a tty color support. It is meant to be used on character
144 terminals whose capabilities are not set correctly in the terminal
145 database, or with terminal emulators which support colors, but don't
146 set the TERM environment variable to a name of a color-capable
147 terminal. "emacs --color" uses the same color commands as GNU `ls'
148 when invoked with "ls --color", so if your terminal can support colors
149 in "ls --color", it will support "emacs --color" as well. See the
150 user manual for the possible values of the MODE parameter.
151
152 ---
153 *** Emacs now supports several character terminals which provide more
154 than 8 colors. For example, for `xterm', 16-color, 88-color, and
155 256-color modes are supported. Emacs automatically notes at startup
156 the extended number of colors, and defines the appropriate entries for
157 all of these colors.
158
159 ---
160 *** There's a new support for colors on `rxvt' terminal emulator.
161
162 +++
163 ** Emacs can now be invoked in full-screen mode on a windowed display.
164
165 When Emacs is invoked on a window system, the new command-line options
166 `--fullwidth', `--fullheight', and `--fullscreen' produce a frame
167 whose width, height, or both width and height take up the entire
168 screen size. (For now, this works only on GNU and Unix systems, and
169 not with every window manager.)
170
171 ** Info-index finally offers completion.
172
173 ** shell-mode now supports programmable completion using `pcomplete'.
174
175 ** Controlling the left and right fringe widths.
176
177 The left and right fringe widths can now be controlled by setting the
178 `left-fringe' and `right-fringe' frame parameters to an integer value
179 specifying the width in pixels. Setting the width to 0 effectively
180 removes the corresponding fringe.
181
182 The actual fringe widths may deviate from the specified widths, since
183 the combined fringe widths must match an integral number of columns.
184 The extra width is distributed evenly between the left and right fringe.
185 For force a specific fringe width, specify the width as a negative
186 integer (if both widths are negative, only the left fringe gets the
187 specified width).
188
189 Setting the width to nil (the default), restores the default fringe
190 width which is the minimum number of pixels necessary to display any
191 of the currently defined fringe bitmaps. The width of the built-in
192 fringe bitmaps is 8 pixels.
193
194 ** Changes in C-h bindings:
195
196 C-h e displays the *Messages* buffer.
197
198 C-h followed by a control character is used for displaying files
199 that do not change:
200
201 C-h C-f displays the FAQ.
202 C-h C-e displays the PROBLEMS file.
203
204 The info-search bindings on C-h C-f, C-h C-k and C-h C-i
205 have been moved to C-h F, C-h K and C-h S.
206
207 C-h c, C-h k, C-h w, and C-h f now handle remapped interactive commands.
208
209 - C-h c and C-h k report the actual command (after possible remapping)
210 run by the key sequence.
211
212 - C-h w and C-h f on a command which has been remapped now report the
213 command it is remapped to, and the keys which can be used to run
214 that command.
215
216 For example, if C-k is bound to kill-line, and kill-line is remapped
217 to new-kill-line, these commands now report:
218
219 - C-h c and C-h k C-k reports:
220 C-k runs the command new-kill-line
221
222 - C-h w and C-h f kill-line reports:
223 kill-line is remapped to new-kill-line which is on C-k, <deleteline>
224
225 - C-h w and C-h f new-kill-line reports:
226 new-kill-line is on C-k
227
228 ** C-w in incremental search now grabs either a character or a word,
229 making the decision in a heuristic way. This new job is done by the
230 command `isearch-yank-word-or-char'. To restore the old behavior,
231 bind C-w to `isearch-yank-word' in `isearch-mode-map'.
232
233 ** In GUD mode when talking to GDB, C-x C-a C-j "jumps" the program
234 counter to the specified source line (the one where point is).
235
236 ** GUD mode improvements for jdb:
237
238 *** Search for source files using jdb classpath and class
239 information. Fast startup since there is no need to scan all
240 source files up front. There is also no need to create and maintain
241 lists of source directories to scan. Look at `gud-jdb-use-classpath'
242 and `gud-jdb-classpath' customization variables documentation.
243
244 *** Supports the standard breakpoint (gud-break, gud-clear)
245 set/clear operations from java source files under the classpath, stack
246 traversal (gud-up, gud-down), and run until current stack finish
247 (gud-finish).
248
249 *** Supports new jdb (Java 1.2 and later) in addition to oldjdb
250 (Java 1.1 jdb).
251
252 *** The previous method of searching for source files has been
253 preserved in case someone still wants/needs to use it.
254 Set gud-jdb-use-classpath to nil.
255
256 Added Customization Variables
257
258 *** gud-jdb-command-name. What command line to use to invoke jdb.
259
260 *** gud-jdb-use-classpath. Allows selection of java source file searching
261 method: set to t for new method, nil to scan gud-jdb-directories for
262 java sources (previous method).
263
264 *** gud-jdb-directories. List of directories to scan and search for java
265 classes using the original gud-jdb method (if gud-jdb-use-classpath
266 is nil).
267
268 Minor Improvements
269
270 *** Do not allow debugger output history variable to grow without bounds.
271
272 ** hide-ifdef-mode now uses overlays rather than selective-display
273 to hide its text. This should be mostly transparent but slightly
274 changes the behavior of motion commands line C-e and C-p.
275
276 ** In Dired's ! command (dired-do-shell-command), `*' and `?' now
277 control substitution of the file names only when they are surrounded
278 by whitespace. This means you can now use them as shell wildcards
279 too. If you want to use just plain `*' as a wildcard, type `*""'; the
280 doublequotes make no difference in the shell, but they prevent
281 special treatment in `dired-do-shell-command'.
282
283 ** Unquoted `$' in file names do not signal an error any more when
284 the corresponding environment variable does not exist.
285 Instead, the `$ENVVAR' text is left as is, so that `$$' quoting
286 is only rarely needed.
287
288 ** jit-lock can now be delayed with `jit-lock-defer-time'.
289
290 If this variable is non-nil, its value should be the amount of Emacs
291 idle time in seconds to wait before starting fontification. For
292 example, if you set `jit-lock-defer-time' to 0.25, fontification will
293 only happen after 0.25s of idle time.
294
295 +++
296 ** Marking commands extend the region when invoked multiple times. If
297 you hit M-C-SPC (mark-sexp), M-@ (mark-word), M-h (mark-paragraph), or
298 C-M-h (mark-defun) repeatedly, the marked region will now be extended
299 each time, so you can mark the next two sexps with M-C-SPC M-C-SPC,
300 for example. This feature also works for mark-end-of-sentence, if you
301 bind that to a key.
302
303 ** In the *Occur* buffer, `o' switches to it in another window, and
304 C-o displays the current line's occurrence in another window without
305 switching to it.
306
307 ** When you specify a frame size with --geometry, the size applies to
308 all frames you create. A position specified with --geometry only
309 affects the initial frame.
310
311 +++
312 ** M-h (mark-paragraph) now accepts a prefix arg.
313 With positive arg, M-h marks the current and the following paragraphs;
314 if the arg is negative, it marks the current and the preceding
315 paragraphs.
316
317 ** In Dired, the w command now copies the current line's file name
318 into the kill ring.
319
320 ** The variables dired-free-space-program and dired-free-space-args
321 have been renamed to directory-free-space-program and
322 directory-free-space-args, and they now apply whenever Emacs puts a
323 directory listing into a buffer.
324
325 ** mouse-wheels can now scroll a specific fraction of the window
326 (rather than a fixed number of lines) and the scrolling is `progressive'.
327
328 ** The keyboard-coding-system is now automatically set based on
329 your current locale settings. If it turns out that your terminal
330 does not support the encoding implied by your locale (for example,
331 it inserts non-ASCII chars if you hit M-i), you will need to add
332
333 (set-keyboard-coding-system nil)
334
335 to your .emacs to revert to the old behavior.
336
337 ** A new coding system `euc-tw' has been added for traditional Chinese
338 in CNS encoding; it accepts both Big 5 and CNS as input; on saving,
339 Big 5 is then converted to CNS.
340
341 +++
342 ** Emacs now reads the standard abbrevs file ~/.abbrev_defs
343 automatically at startup, if it exists. When Emacs offers to save
344 modified buffers, it saves the abbrevs too if they have changed. It
345 can do this either silently or asking for confirmation first,
346 according to the value of `save-abbrevs'.
347
348 ** Display of hollow cursors now obeys the buffer-local value (if any)
349 of `cursor-in-non-selected-windows' in the buffer that the cursor
350 appears in.
351
352 ** The default values of `tooltip-delay' and `tooltip-hide-delay'
353 were changed.
354
355 ** On terminals whose erase-char is ^H (Backspace), Emacs
356 now uses normal-erase-is-backspace-mode.
357
358 ** Etags changes.
359
360 *** In Prolog, etags creates tags for rules in addition to predicates.
361
362 *** In Perl, packages are tags. Subroutine tags are named from their
363 package. You can jump to sub tags as you did before, by the sub name, or
364 additionally by looking for package::sub.
365
366 *** New language PHP: tags are functions, classes and defines. If
367 the --members option is specified to etags, tags are vars also.
368
369 *** Honour #line directives. This is useful when dealing with C code
370 created from Yacc sources, or with any file created from Cweb source
371 files. When etags tags the generated file, it writes tags pointing to
372 the source file.
373
374 +++
375 ** The command line option --no-windows has been changed to
376 --no-window-system. The old one still works, but is deprecated.
377
378 ** `buffer-menu' and `list-buffers' now list buffers whose names begin
379 with a space, if they visit files.
380
381 ** You can now customize fill-nobreak-predicate to control where
382 filling can break lines. We provide two sample predicates,
383 fill-single-word-nobreak-p and fill-french-nobreak-p.
384
385 ** New user option `add-log-always-start-new-record'.
386 When this option is enabled, M-x add-change-log-entry will always
387 start a new record regardless of when the last record is.
388
389 ** New user option `sgml-xml'.
390 When this option is enabled, SGML tags are inserted in XML style,
391 i.e., there is always a closing tag.
392 When not customized, it becomes buffer-local when it can be inferred
393 from the file name or buffer contents.
394
395 ** New user option `isearch-resume-enabled'.
396 This option can be disabled, to avoid the normal behaviour of isearch
397 which puts calls to `isearch-resume' in the command history.
398
399 ** When the *scratch* buffer is recreated, its mode is set from
400 initial-major-mode, which normally is lisp-interaction-mode,
401 instead of using default-major-mode.
402
403 ** Byte compiler warning and error messages have been brought more
404 in line with the output of other GNU tools.
405
406 ** Lisp-mode now uses font-lock-doc-face for the docstrings.
407
408 ** perl-mode has a new variable `perl-indent-continued-arguments'.
409
410 ** `special-display-buffer-names' and `special-display-regexps' now
411 understand two new boolean pseudo-frame-parameters `same-frame' and
412 `same-window'.
413
414 ** When pure storage overflows while dumping, Emacs now prints how
415 much pure storage it will approximately need.
416
417 ** M-x setenv now expands environment variables of the form `$foo' and
418 `${foo}' in the specified new value of the environment variable. To
419 include a `$' in the value, use `$$'.
420
421 +++
422 ** File-name completion can now ignore directories.
423 If an element of the list in `completion-ignored-extensions' ends in a
424 slash `/', it indicates a subdirectory that should be ignored when
425 completing file names. Elements of `completion-ignored-extensions'
426 which do not end in a slash are never considered when a completion
427 candidate is a directory.
428
429 ** New user option `inhibit-startup-buffer-menu'.
430 When loading many files, for instance with `emacs *', Emacs normally
431 displays a buffer menu. This option turns the buffer menu off.
432
433 ** Rmail now displays 5-digit message ids in its summary buffer.
434
435 ** When using M-x revert-buffer in a compilation buffer to rerun a
436 compilation, it is now made sure that the compilation buffer is reused
437 in case it has been renamed.
438
439 ** On MS Windows, the "system caret" now follows the cursor.
440 This enables Emacs to work better with programs that need to track
441 the cursor, for example screen magnifiers and text to speech programs.
442
443 ** Tooltips now work on MS Windows.
444 See the Emacs 21.1 NEWS entry for tooltips for details.
445
446 ** Pointing devices with more than 3 buttons are now supported on MS Windows.
447 The new variable `w32-pass-extra-mouse-buttons-to-system' controls
448 whether Emacs should handle the extra buttons itself (the default), or
449 pass them to Windows to be handled with system-wide functions.
450
451 ** Under X11, it is possible to swap Alt and Meta (and Super and Hyper).
452 The new variables `x-alt-keysym', `x-hyper-keysym', `x-meta-keysym',
453 and `x-super-keysym' can be used to choose which keysyms Emacs should
454 use for the modifiers. For example, the following two lines swap
455 Meta and Alt:
456 (setq x-alt-keysym 'meta)
457 (setq x-meta-keysym 'alt)
458
459 ---
460 ** A French translation of the `Emacs Survival Guide' is available.
461
462 ---
463 ** A French translation of the Emacs Tutorial is available.
464
465 ** New modes and packages
466
467 +++
468 *** Calc is now part of the Emacs distribution.
469
470 Calc is an advanced desk calculator and mathematical tool written in
471 Emacs Lisp. Its documentation is in a separate manual; within Emacs,
472 type "C-h i m calc RET" to read that manual. A reference card is
473 available in `etc/calccard.tex' and `etc/calccard.ps'.
474
475 +++
476 *** The Emacs Lisp Reference Manual is now part of the distribution.
477
478 The ELisp reference manual in Info format is built as part of the
479 Emacs build procedure and installed together with the Emacs User
480 Manual. A menu item was added to the menu bar that makes it easy
481 accessible (Help->More Manuals->Emacs Lisp Reference).
482
483 *** The Introduction to Programming in Emacs Lisp manual is now part of
484 the distribution.
485
486 This manual is now part of the standard distribution and is installed,
487 together with the Emacs User Manual, into the Info directory. A menu
488 item was added to the menu bar that makes it easy accessible
489 (Help->More Manuals->Introduction to Emacs Lisp).
490
491 *** The ruler-mode.el library provides a minor mode for displaying an
492 "active" ruler in the header line. You can use the mouse to visually
493 change the `fill-column', `window-margins' and `tab-stop-list'
494 settings.
495
496 *** The reveal.el package provides the minor modes `reveal-mode' and
497 `global-reveal-mode' which will make text visible on the fly as you
498 move your cursor into hidden region of the buffer.
499 It should work with any package that uses overlays to hide parts
500 of a buffer, such as outline-minor-mode, hs-minor-mode, hide-ifdef-mode, ...
501
502 *** master-mode.el implements a minor mode for scrolling a slave
503 buffer without leaving your current buffer, the master buffer.
504
505 It can be used by sql.el, for example: the SQL buffer is the master
506 and its SQLi buffer is the slave. This allows you to scroll the SQLi
507 buffer containing the output from the SQL buffer containing the
508 commands.
509
510 This is how to use sql.el and master.el together: the variable
511 sql-buffer contains the slave buffer. It is a local variable in the
512 SQL buffer.
513
514 (add-hook 'sql-mode-hook
515 (function (lambda ()
516 (master-mode t)
517 (master-set-slave sql-buffer))))
518 (add-hook 'sql-set-sqli-hook
519 (function (lambda ()
520 (master-set-slave sql-buffer))))
521
522 \f
523 * Lisp Changes in Emacs 21.3
524
525 ** Interactive commands can be remapped through keymaps.
526
527 This is an alternative to using defadvice or substitute-key-definition
528 to modify the behaviour of a key binding using the normal keymap
529 binding and lookup functionality.
530
531 When a key sequence is bound to a command, and that command is
532 remapped to another command, that command is run instead of the
533 original command.
534
535 Example:
536 Suppose that minor mode my-mode has defined the commands
537 my-kill-line and my-kill-word, and it wants C-k (and any other key
538 bound to kill-line) to run the command my-kill-line instead of
539 kill-line, and likewise it wants to run my-kill-word instead of
540 kill-word.
541
542 Instead of rebinding C-k and the other keys in the minor mode map,
543 command remapping allows you to directly map kill-line into
544 my-kill-line and kill-word into my-kill-word through the minor mode
545 map using define-key:
546
547 (define-key my-mode-map [remap kill-line] 'my-kill-line)
548 (define-key my-mode-map [remap kill-word] 'my-kill-word)
549
550 Now, when my-mode is enabled, and the user enters C-k or M-d,
551 the commands my-kill-line and my-kill-word are run.
552
553 Notice that only one level of remapping is supported. In the above
554 example, this means that if my-kill-line is remapped to other-kill,
555 then C-k still runs my-kill-line.
556
557 The following changes have been made to provide command remapping:
558
559 - Command remappings are defined using `define-key' with a prefix-key
560 `remap', i.e. `(define-key MAP [remap CMD] DEF)' remaps command CMD
561 to definition DEF in keymap MAP. The definition is not limited to
562 another command; it can be anything accepted for a normal binding.
563
564 - The new function `remap-command' returns the binding for a remapped
565 command in the current keymaps, or nil if it isn't remapped.
566
567 - key-binding now remaps interactive commands unless the optional
568 third argument NO-REMAP is non-nil.
569
570 - where-is-internal now returns nil for a remapped command (e.g.
571 kill-line if my-mode is enabled), and the actual key binding for
572 the command it is remapped to (e.g. C-k for my-kill-line).
573 It also has a new optional fifth argument, NO-REMAP, which inhibits
574 remapping if non-nil (e.g. it returns C-k for kill-line and
575 <kill-line> for my-kill-line).
576
577 - The new variable `this-original-command' contains the original
578 command before remapping. It is equal to `this-command' when the
579 command was not remapped.
580
581 ** Atomic change groups.
582
583 To perform some changes in the current buffer "atomically" so that
584 they either all succeed or are all undone, use `atomic-change-group'
585 around the code that makes changes. For instance:
586
587 (atomic-change-group
588 (insert foo)
589 (delete-region x y))
590
591 If an error (or other nonlocal exit) occurs inside the body of
592 `atomic-change-group', it unmakes all the changes in that buffer that
593 were during the execution of the body. The change group has no effect
594 on any other buffers--any such changes remain.
595
596 If you need something more sophisticated, you can directly call the
597 lower-level functions that `atomic-change-group' uses. Here is how.
598
599 To set up a change group for one buffer, call `prepare-change-group'.
600 Specify the buffer as argument; it defaults to the current buffer.
601 This function returns a "handle" for the change group. You must save
602 the handle to activate the change group and then finish it.
603
604 Before you change the buffer again, you must activate the change
605 group. Pass the handle to `activate-change-group' afterward to
606 do this.
607
608 After you make the changes, you must finish the change group. You can
609 either accept the changes or cancel them all. Call
610 `accept-change-group' to accept the changes in the group as final;
611 call `cancel-change-group' to undo them all.
612
613 You should use `unwind-protect' to make sure the group is always
614 finished. The call to `activate-change-group' should be inside the
615 `unwind-protect', in case the user types C-g just after it runs.
616 (This is one reason why `prepare-change-group' and
617 `activate-change-group' are separate functions.) Once you finish the
618 group, don't use the handle again--don't try to finish the same group
619 twice.
620
621 To make a multibuffer change group, call `prepare-change-group' once
622 for each buffer you want to cover, then use `nconc' to combine the
623 returned values, like this:
624
625 (nconc (prepare-change-group buffer-1)
626 (prepare-change-group buffer-2))
627
628 You can then activate the multibuffer change group with a single call
629 to `activate-change-group', and finish it with a single call to
630 `accept-change-group' or `cancel-change-group'.
631
632 Nested use of several change groups for the same buffer works as you
633 would expect. Non-nested use of change groups for the same buffer
634 will lead to undesirable results, so don't let it happen; the first
635 change group you start for any given buffer should be the last one
636 finished.
637
638 ** You can now use non-blocking connect to open network streams.
639
640 The function open-network-stream has a new optional 7th argument.
641 If non-nil, that function will initiate a non-blocking connect and
642 return immediately before the connection is established.
643
644 It returns nil if the system does not support non-blocking connects;
645 the caller may then make a normal (blocking) open-network-stream.
646
647 The filter and sentinel functions can now be specified as arguments
648 to open-network-stream. When the non-blocking connect completes, the
649 sentinel is called with the status matching "open" or "failed".
650
651 ** New function substring-no-properties.
652
653 ** New function minibuffer-selected-window.
654
655 +++
656 *** The meanings of scroll-up-aggressively and scroll-down-aggressively
657 have been interchanged, so that the former now controls scrolling up,
658 and the latter now controls scrolling down.
659
660 +++
661 ** New function window-body-height.
662
663 This is like window-height but does not count the mode line
664 or the header line.
665
666 +++
667 ** The function `atan' now accepts an optional second argument.
668
669 When called with 2 arguments, as in `(atan Y X)', `atan' returns the
670 angle in radians between the vector [X, Y] and the X axis. (This is
671 equivalent to the standard C library function `atan2'.)
672
673 +++
674 ** You can now make a window as short as one line.
675
676 A window that is just one line tall does not display either a mode
677 line or a header line, even if the variables `mode-line-format' and
678 `header-line-format' call for them. A window that is two lines tall
679 cannot display both a mode line and a header line at once; if the
680 variables call for both, only the mode line actually appears.
681
682 +++
683 ** The new frame parameter `tty-color-mode' specifies the mode to use
684 for color support on character terminal frames. Its value can be a
685 number of colors to support, or a symbol. See the Emacs Lisp
686 Reference manual for more detailed documentation.
687
688 ** Already true in Emacs 21.1, but not emphasized clearly enough:
689
690 Multibyte buffers can now faithfully record all 256 character codes
691 from 0 to 255. As a result, most of the past reasons to use unibyte
692 buffers no longer exist. We only know of three reasons to use them
693 now:
694
695 1. If you prefer to use unibyte text all of the time.
696
697 2. For reading files into temporary buffers, when you want to avoid
698 the time it takes to convert the format.
699
700 3. For binary files where format conversion would be pointless and
701 wasteful.
702
703 ** If text has a `keymap' property, that keymap takes precedence
704 over minor mode keymaps.
705
706 ** A hex escape in a string forces the string to be multibyte.
707 An octal escape makes it unibyte.
708
709 ** The position after an invisible, intangible character
710 is considered an unacceptable value for point;
711 intangibility processing effectively treats the following character
712 as part of the intangible region even if it is not itself intangible.
713
714 Thus, point can go before an invisible, intangible region, but not
715 after it. This prevents C-f and C-b from appearing to stand still on
716 the screen.
717
718 +++
719 ** define-abbrev now accepts an optional argument SYSTEM-FLAG. If
720 non-nil, this marks the abbrev as a "system" abbrev, which means that
721 it won't be stored in the user's abbrevs file if he saves the abbrevs.
722 Major modes that predefine some abbrevs should always specify this
723 flag.
724
725 ** Support for Mocklisp has been removed.
726
727 ** The function insert-string is now obsolete.
728
729 ** The precedence of file-name-handlers has been changed.
730 Instead of blindly choosing the first handler that matches,
731 find-file-name-handler now gives precedence to a file-name handler
732 that matches near the end of the file name. More specifically, the
733 handler whose (match-beginning 0) is the largest is chosen.
734 In case of ties, the old "first matched" rule applies.
735
736 ** Dense keymaps now handle inheritance correctly.
737 Previously a dense keymap would hide all of the simple-char key
738 bindings of the parent keymap.
739
740 ** jit-lock obeys a new text-property `jit-lock-defer-multiline'.
741 If a piece of text with that property gets contextually refontified
742 (see jit-lock-defer-contextually), then all of that text will
743 be refontified. This is useful when the syntax of a textual element
744 depends on text several lines further down (and when font-lock-multiline
745 is not appropriate to solve that problem). For example in Perl:
746
747 s{
748 foo
749 }{
750 bar
751 }e
752
753 Adding/removing the last `e' changes the `bar' from being a piece of
754 text to being a piece of code, so you'd put a jit-lock-defer-multiline
755 property over the second half of the command to force (deferred)
756 refontification of `bar' whenever the `e' is added/removed.
757
758 ** describe-vector now takes a second argument `describer' which is
759 called to print the entries' values. It defaults to `princ'.
760
761 ** defcustom and other custom declarations now use a default group
762 (the last group defined in the same file) when no :group was given.
763
764 ** emacsserver now runs pre-command-hook and post-command-hook when
765 it receives a request from emacsclient.
766
767 ** The variable `recursive-load-depth-limit' has been deleted.
768 Emacs now signals an error if the same file is loaded with more
769 than 3 levels of nesting.
770
771 ** The default values of paragraph-start and indent-line-function have
772 been changed to reflect those used in Text mode rather than those used
773 in Indented-Text mode.
774
775 ** If a major mode function has a non-nil `no-clone-indirect'
776 property, `clone-indirect-buffer' signals an error if you use
777 it in that buffer.
778
779 ** If you set `query-replace-skip-read-only' non-nil,
780 `query-replace' and related functions simply ignore
781 a match if part of it has a read-only property.
782
783 ** In `replace-match', the replacement text no longer inherits
784 properties from surrounding text.
785
786 ** New function `buffer-local-value'.
787
788 - Function: buffer-local-value variable buffer
789
790 This function returns the buffer-local binding of VARIABLE (a symbol)
791 in buffer BUFFER. If VARIABLE does not have a buffer-local binding in
792 buffer BUFFER, it returns the default value of VARIABLE instead.
793
794 ** The default value of `paragraph-start' and `indent-line-function' has
795 been changed to reflect the one used in Text mode rather than the one
796 used in Indented Text mode.
797
798 ** New function `text-clone-create'. Text clones are chunks of text
799 that are kept identical by transparently propagating changes from one
800 clone to the other.
801
802 ** font-lock can manage arbitrary text-properties beside `face'.
803 *** the FACENAME returned in font-lock-keywords can be a list
804 of the form (face FACE PROP1 VAL1 PROP2 VAL2 ...) so you can set
805 other properties than `face'.
806 *** font-lock-extra-managed-props can be set to make sure those extra
807 properties are automatically cleaned up by font-lock.
808
809 ** The new function `run-mode-hooks' and the new macro `delay-mode-hooks'
810 are used by define-derived-mode to make sure the mode hook for the
811 parent mode is run at the end of the child mode.
812
813 ** `provide' and `featurep' now accept an optional second argument
814 to test/provide subfeatures. Also `provide' now checks `after-load-alist'
815 and run any code associated with the provided feature.
816
817 ** The variable `compilation-parse-errors-filename-function' can
818 be used to transform filenames found in compilation output.
819
820 +++
821 ** Functions `file-name-sans-extension' and `file-name-extension' now
822 ignore the leading dots in file names, so that file names such as
823 `.emacs' are treated as extensionless.
824
825 ** Functions `user-uid' and `user-real-uid' now return floats if the
826 user UID doesn't fit in a Lisp integer. Function `user-full-name'
827 accepts a float as UID parameter.
828
829 ** `define-key-after' now accepts keys longer than 1.
830
831 ** `define-derived-mode' now accepts nil as the parent.
832
833 ** The local variable `no-byte-compile' in elisp files is now obeyed.
834
835 ** New functions `keymap-prompt' and `current-active-maps'.
836
837 ** New function `describe-buffer-bindings'.
838
839 ** New vars `exec-suffixes' and `load-suffixes' used when
840 searching for an executable resp. an elisp file.
841
842 ** Variable aliases have been implemented
843
844 - Macro: defvaralias ALIAS-VAR BASE-VAR
845
846 This defines the symbol ALIAS-VAR as a variable alias for symbol
847 BASE-VAR. This means that retrieving the value of ALIAS-VAR returns
848 the value of BASE-VAR, and changing the value of ALIAS-VAR changes the
849 value of BASE-VAR.
850
851 - Function: indirect-variable VARIABLE
852
853 This function returns the variable at the end of the chain of aliases
854 of VARIABLE. If VARIABLE is not a symbol, or if VARIABLE is not
855 defined as an alias, the function returns VARIABLE.
856
857 It might be noteworthy that variables aliases work for all kinds of
858 variables, including buffer-local and frame-local variables.
859
860 ** Functions from `post-gc-hook' are run at the end of garbage
861 collection. The hook is run with GC inhibited, so use it with care.
862
863 ** If the second argument to `copy-file' is the name of a directory,
864 the file is copied to that directory instead of signaling an error.
865
866 ** The variables most-positive-fixnum and most-negative-fixnum
867 have been moved from the CL package to the core.
868
869 ** On MS Windows, locale-coding-system is used to interact with the OS.
870 The Windows specific variable w32-system-coding-system, which was
871 formerly used for that purpose is now an alias for locale-coding-system.
872
873 ** Functions y-or-n-p, read-char, read-keysequence and alike that
874 display a prompt but don't use the minibuffer now display the prompt
875 using the text properties (esp. the face) of the prompt string.
876
877 ** New packages:
878
879 *** The new package syntax.el provides an efficient way to find the
880 current syntactic context (as returned by parse-partial-sexp).
881
882 *** The TCL package tcl-mode.el was replaced by tcl.el.
883 This was actually done in Emacs-21.1, and was not documented.
884
885 *** The new package Ibuffer provides a powerful, completely
886 customizable replacement for buff-menu.el.
887
888 \f
889 * Installation Changes in Emacs 21.1
890
891 See the INSTALL file for information on installing extra libraries and
892 fonts to take advantage of the new graphical features and extra
893 charsets in this release.
894
895 ** Support for GNU/Linux on IA64 machines has been added.
896
897 ** Support for LynxOS has been added.
898
899 ** There are new configure options associated with the support for
900 images and toolkit scrollbars. Use the --help option in `configure'
901 to list them.
902
903 ** You can build a 64-bit Emacs for SPARC/Solaris systems which
904 support 64-bit executables and also on Irix 6.5. This increases the
905 maximum buffer size. See etc/MACHINES for instructions. Changes to
906 build on other 64-bit systems should be straightforward modulo any
907 necessary changes to unexec.
908
909 ** There is a new configure option `--disable-largefile' to omit
910 Unix-98-style support for large files if that is available.
911
912 ** There is a new configure option `--without-xim' that instructs
913 Emacs to not use X Input Methods (XIM), if these are available.
914
915 ** `movemail' defaults to supporting POP. You can turn this off using
916 the --without-pop configure option, should that be necessary.
917
918 ** This version can be built for the Macintosh, but does not implement
919 all of the new display features described below. The port currently
920 lacks unexec, asynchronous processes, and networking support. See the
921 "Emacs and the Mac OS" appendix in the Emacs manual, for the
922 description of aspects specific to the Mac.
923
924 ** Note that the MS-Windows port does not yet implement various of the
925 new display features described below.
926
927 \f
928 * Changes in Emacs 21.1
929
930 ** Emacs has a new redisplay engine.
931
932 The new redisplay handles characters of variable width and height.
933 Italic text can be used without redisplay problems. Fonts containing
934 oversized characters, i.e. characters larger than the logical height
935 of a font can be used. Images of various formats can be displayed in
936 the text.
937
938 ** Emacs has a new face implementation.
939
940 The new faces no longer fundamentally use X font names to specify the
941 font. Instead, each face has several independent attributes--family,
942 height, width, weight and slant--that it may or may not specify.
943 These attributes can be merged from various faces, and then together
944 specify a font.
945
946 Faces are supported on terminals that can display color or fonts.
947 These terminal capabilities are auto-detected. Details can be found
948 under Lisp changes, below.
949
950 ** Emacs can display faces on TTY frames.
951
952 Emacs automatically detects terminals that are able to display colors.
953 Faces with a weight greater than normal are displayed extra-bright, if
954 the terminal supports it. Faces with a weight less than normal and
955 italic faces are displayed dimmed, if the terminal supports it.
956 Underlined faces are displayed underlined if possible. Other face
957 attributes such as `overline', `strike-through', and `box' are ignored
958 on terminals.
959
960 The command-line options `-fg COLOR', `-bg COLOR', and `-rv' are now
961 supported on character terminals.
962
963 Emacs automatically remaps all X-style color specifications to one of
964 the colors supported by the terminal. This means you could have the
965 same color customizations that work both on a windowed display and on
966 a TTY or when Emacs is invoked with the -nw option.
967
968 ** New default font is Courier 12pt under X.
969
970 ** Sound support
971
972 Emacs supports playing sound files on GNU/Linux and FreeBSD (Voxware
973 driver and native BSD driver, a.k.a. Luigi's driver). Currently
974 supported file formats are RIFF-WAVE (*.wav) and Sun Audio (*.au).
975 You must configure Emacs with the option `--with-sound=yes' to enable
976 sound support.
977
978 ** Emacs now resizes mini-windows if appropriate.
979
980 If a message is longer than one line, or minibuffer contents are
981 longer than one line, Emacs can resize the minibuffer window unless it
982 is on a frame of its own. You can control resizing and the maximum
983 minibuffer window size by setting the following variables:
984
985 - User option: max-mini-window-height
986
987 Maximum height for resizing mini-windows. If a float, it specifies a
988 fraction of the mini-window frame's height. If an integer, it
989 specifies a number of lines.
990
991 Default is 0.25.
992
993 - User option: resize-mini-windows
994
995 How to resize mini-windows. If nil, don't resize. If t, always
996 resize to fit the size of the text. If `grow-only', let mini-windows
997 grow only, until they become empty, at which point they are shrunk
998 again.
999
1000 Default is `grow-only'.
1001
1002 ** LessTif support.
1003
1004 Emacs now runs with the LessTif toolkit (see
1005 <http://www.lesstif.org>). You will need version 0.92.26, or later.
1006
1007 ** LessTif/Motif file selection dialog.
1008
1009 When Emacs is configured to use LessTif or Motif, reading a file name
1010 from a menu will pop up a file selection dialog if `use-dialog-box' is
1011 non-nil.
1012
1013 ** File selection dialog on MS-Windows is supported.
1014
1015 When a file is visited by clicking File->Open, the MS-Windows version
1016 now pops up a standard file selection dialog where you can select a
1017 file to visit. File->Save As also pops up that dialog.
1018
1019 ** Toolkit scroll bars.
1020
1021 Emacs now uses toolkit scroll bars if available. When configured for
1022 LessTif/Motif, it will use that toolkit's scroll bar. Otherwise, when
1023 configured for Lucid and Athena widgets, it will use the Xaw3d scroll
1024 bar if Xaw3d is available. You can turn off the use of toolkit scroll
1025 bars by specifying `--with-toolkit-scroll-bars=no' when configuring
1026 Emacs.
1027
1028 When you encounter problems with the Xaw3d scroll bar, watch out how
1029 Xaw3d is compiled on your system. If the Makefile generated from
1030 Xaw3d's Imakefile contains a `-DNARROWPROTO' compiler option, and your
1031 Emacs system configuration file `s/your-system.h' does not contain a
1032 define for NARROWPROTO, you might consider adding it. Take
1033 `s/freebsd.h' as an example.
1034
1035 Alternatively, if you don't have access to the Xaw3d source code, take
1036 a look at your system's imake configuration file, for example in the
1037 directory `/usr/X11R6/lib/X11/config' (paths are different on
1038 different systems). You will find files `*.cf' there. If your
1039 system's cf-file contains a line like `#define NeedWidePrototypes NO',
1040 add a `#define NARROWPROTO' to your Emacs system configuration file.
1041
1042 The reason for this is that one Xaw3d function uses `double' or
1043 `float' function parameters depending on the setting of NARROWPROTO.
1044 This is not a problem when Imakefiles are used because each system's
1045 imake configuration file contains the necessary information. Since
1046 Emacs doesn't use imake, this has do be done manually.
1047
1048 ** Tool bar support.
1049
1050 Emacs supports a tool bar at the top of a frame under X. For details
1051 of how to define a tool bar, see the page describing Lisp-level
1052 changes. Tool-bar global minor mode controls whether or not it is
1053 displayed and is on by default. The appearance of the bar is improved
1054 if Emacs has been built with XPM image support. Otherwise monochrome
1055 icons will be used.
1056
1057 To make the tool bar more useful, we need contributions of extra icons
1058 for specific modes (with copyright assignments).
1059
1060 ** Tooltips.
1061
1062 Tooltips are small X windows displaying a help string at the current
1063 mouse position. The Lisp package `tooltip' implements them. You can
1064 turn them off via the user option `tooltip-mode'.
1065
1066 Tooltips also provides support for GUD debugging. If activated,
1067 variable values can be displayed in tooltips by pointing at them with
1068 the mouse in source buffers. You can customize various aspects of the
1069 tooltip display in the group `tooltip'.
1070
1071 ** Automatic Hscrolling
1072
1073 Horizontal scrolling now happens automatically if
1074 `automatic-hscrolling' is set (the default). This setting can be
1075 customized.
1076
1077 If a window is scrolled horizontally with set-window-hscroll, or
1078 scroll-left/scroll-right (C-x <, C-x >), this serves as a lower bound
1079 for automatic horizontal scrolling. Automatic scrolling will scroll
1080 the text more to the left if necessary, but won't scroll the text more
1081 to the right than the column set with set-window-hscroll etc.
1082
1083 ** When using a windowing terminal, each Emacs window now has a cursor
1084 of its own. By default, when a window is selected, the cursor is
1085 solid; otherwise, it is hollow. The user-option
1086 `cursor-in-non-selected-windows' controls how to display the
1087 cursor in non-selected windows. If nil, no cursor is shown, if
1088 non-nil a hollow box cursor is shown.
1089
1090 ** Fringes to the left and right of windows are used to display
1091 truncation marks, continuation marks, overlay arrows and alike. The
1092 foreground, background, and stipple of these areas can be changed by
1093 customizing face `fringe'.
1094
1095 ** The mode line under X is now drawn with shadows by default.
1096 You can change its appearance by modifying the face `mode-line'.
1097 In particular, setting the `:box' attribute to nil turns off the 3D
1098 appearance of the mode line. (The 3D appearance makes the mode line
1099 occupy more space, and thus might cause the first or the last line of
1100 the window to be partially obscured.)
1101
1102 The variable `mode-line-inverse-video', which was used in older
1103 versions of emacs to make the mode-line stand out, is now deprecated.
1104 However, setting it to nil will cause the `mode-line' face to be
1105 ignored, and mode-lines to be drawn using the default text face.
1106
1107 ** Mouse-sensitive mode line.
1108
1109 Different parts of the mode line have been made mouse-sensitive on all
1110 systems which support the mouse. Moving the mouse to a
1111 mouse-sensitive part in the mode line changes the appearance of the
1112 mouse pointer to an arrow, and help about available mouse actions is
1113 displayed either in the echo area, or in the tooltip window if you
1114 have enabled one.
1115
1116 Currently, the following actions have been defined:
1117
1118 - Mouse-1 on the buffer name in the mode line goes to the next buffer.
1119
1120 - Mouse-3 on the buffer-name goes to the previous buffer.
1121
1122 - Mouse-2 on the read-only or modified status in the mode line (`%' or
1123 `*') toggles the status.
1124
1125 - Mouse-3 on the mode name displays a minor-mode menu.
1126
1127 ** Hourglass pointer
1128
1129 Emacs can optionally display an hourglass pointer under X. You can
1130 turn the display on or off by customizing group `cursor'.
1131
1132 ** Blinking cursor
1133
1134 M-x blink-cursor-mode toggles a blinking cursor under X and on
1135 terminals having terminal capabilities `vi', `vs', and `ve'. Blinking
1136 and related parameters like frequency and delay can be customized in
1137 the group `cursor'.
1138
1139 ** New font-lock support mode `jit-lock-mode'.
1140
1141 This support mode is roughly equivalent to `lazy-lock' but is
1142 generally faster. It supports stealth and deferred fontification.
1143 See the documentation of the function `jit-lock-mode' for more
1144 details.
1145
1146 Font-lock uses jit-lock-mode as default support mode, so you don't
1147 have to do anything to activate it.
1148
1149 ** The default binding of the Delete key has changed.
1150
1151 The new user-option `normal-erase-is-backspace' can be set to
1152 determine the effect of the Delete and Backspace function keys.
1153
1154 On window systems, the default value of this option is chosen
1155 according to the keyboard used. If the keyboard has both a Backspace
1156 key and a Delete key, and both are mapped to their usual meanings, the
1157 option's default value is set to t, so that Backspace can be used to
1158 delete backward, and Delete can be used to delete forward. On
1159 keyboards which either have only one key (usually labeled DEL), or two
1160 keys DEL and BS which produce the same effect, the option's value is
1161 set to nil, and these keys delete backward.
1162
1163 If not running under a window system, setting this option accomplishes
1164 a similar effect by mapping C-h, which is usually generated by the
1165 Backspace key, to DEL, and by mapping DEL to C-d via
1166 `keyboard-translate'. The former functionality of C-h is available on
1167 the F1 key. You should probably not use this setting on a text-only
1168 terminal if you don't have both Backspace, Delete and F1 keys.
1169
1170 Programmatically, you can call function normal-erase-is-backspace-mode
1171 to toggle the behavior of the Delete and Backspace keys.
1172
1173 ** The default for user-option `next-line-add-newlines' has been
1174 changed to nil, i.e. C-n will no longer add newlines at the end of a
1175 buffer by default.
1176
1177 ** The <home> and <end> keys now move to the beginning or end of the
1178 current line, respectively. C-<home> and C-<end> move to the
1179 beginning and end of the buffer.
1180
1181 ** Emacs now checks for recursive loads of Lisp files. If the
1182 recursion depth exceeds `recursive-load-depth-limit', an error is
1183 signaled.
1184
1185 ** When an error is signaled during the loading of the user's init
1186 file, Emacs now pops up the *Messages* buffer.
1187
1188 ** Emacs now refuses to load compiled Lisp files which weren't
1189 compiled with Emacs. Set `load-dangerous-libraries' to t to change
1190 this behavior.
1191
1192 The reason for this change is an incompatible change in XEmacs's byte
1193 compiler. Files compiled with XEmacs can contain byte codes that let
1194 Emacs dump core.
1195
1196 ** Toggle buttons and radio buttons in menus.
1197
1198 When compiled with LessTif (or Motif) support, Emacs uses toolkit
1199 widgets for radio and toggle buttons in menus. When configured for
1200 Lucid, Emacs draws radio buttons and toggle buttons similar to Motif.
1201
1202 ** The menu bar configuration has changed. The new configuration is
1203 more CUA-compliant. The most significant change is that Options is
1204 now a separate menu-bar item, with Mule and Customize as its submenus.
1205
1206 ** Item Save Options on the Options menu allows saving options set
1207 using that menu.
1208
1209 ** Highlighting of trailing whitespace.
1210
1211 When `show-trailing-whitespace' is non-nil, Emacs displays trailing
1212 whitespace in the face `trailing-whitespace'. Trailing whitespace is
1213 defined as spaces or tabs at the end of a line. To avoid busy
1214 highlighting when entering new text, trailing whitespace is not
1215 displayed if point is at the end of the line containing the
1216 whitespace.
1217
1218 ** C-x 5 1 runs the new command delete-other-frames which deletes
1219 all frames except the selected one.
1220
1221 ** The new user-option `confirm-kill-emacs' can be customized to
1222 let Emacs ask for confirmation before exiting.
1223
1224 ** The header line in an Info buffer is now displayed as an emacs
1225 header-line (which is like a mode-line, but at the top of the window),
1226 so that it remains visible even when the buffer has been scrolled.
1227 This behavior may be disabled by customizing the option
1228 `Info-use-header-line'.
1229
1230 ** Polish, Czech, German, and French translations of Emacs' reference card
1231 have been added. They are named `pl-refcard.tex', `cs-refcard.tex',
1232 `de-refcard.tex' and `fr-refcard.tex'. Postscript files are included.
1233
1234 ** An `Emacs Survival Guide', etc/survival.tex, is available.
1235
1236 ** A reference card for Dired has been added. Its name is
1237 `dired-ref.tex'. A French translation is available in
1238 `fr-drdref.tex'.
1239
1240 ** C-down-mouse-3 is bound differently. Now if the menu bar is not
1241 displayed it pops up a menu containing the items which would be on the
1242 menu bar. If the menu bar is displayed, it pops up the major mode
1243 menu or the Edit menu if there is no major mode menu.
1244
1245 ** Variable `load-path' is no longer customizable through Customize.
1246
1247 You can no longer use `M-x customize-variable' to customize `load-path'
1248 because it now contains a version-dependent component. You can still
1249 use `add-to-list' and `setq' to customize this variable in your
1250 `~/.emacs' init file or to modify it from any Lisp program in general.
1251
1252 ** C-u C-x = provides detailed information about the character at
1253 point in a pop-up window.
1254
1255 ** Emacs can now support 'wheeled' mice (such as the MS IntelliMouse)
1256 under XFree86. To enable this, use the `mouse-wheel-mode' command, or
1257 customize the variable `mouse-wheel-mode'.
1258
1259 The variables `mouse-wheel-follow-mouse' and `mouse-wheel-scroll-amount'
1260 determine where and by how much buffers are scrolled.
1261
1262 ** Emacs' auto-save list files are now by default stored in a
1263 sub-directory `.emacs.d/auto-save-list/' of the user's home directory.
1264 (On MS-DOS, this subdirectory's name is `_emacs.d/auto-save.list/'.)
1265 You can customize `auto-save-list-file-prefix' to change this location.
1266
1267 ** The function `getenv' is now callable interactively.
1268
1269 ** The new user-option `even-window-heights' can be set to nil
1270 to prevent `display-buffer' from evening out window heights.
1271
1272 ** The new command M-x delete-trailing-whitespace RET will delete the
1273 trailing whitespace within the current restriction. You can also add
1274 this function to `write-file-hooks' or `local-write-file-hooks'.
1275
1276 ** When visiting a file with M-x find-file-literally, no newlines will
1277 be added to the end of the buffer even if `require-final-newline' is
1278 non-nil.
1279
1280 ** The new user-option `find-file-suppress-same-file-warnings' can be
1281 set to suppress warnings ``X and Y are the same file'' when visiting a
1282 file that is already visited under a different name.
1283
1284 ** The new user-option `electric-help-shrink-window' can be set to
1285 nil to prevent adjusting the help window size to the buffer size.
1286
1287 ** New command M-x describe-character-set reads a character set name
1288 and displays information about that.
1289
1290 ** The new variable `auto-mode-interpreter-regexp' contains a regular
1291 expression matching interpreters, for file mode determination.
1292
1293 This regular expression is matched against the first line of a file to
1294 determine the file's mode in `set-auto-mode' when Emacs can't deduce a
1295 mode from the file's name. If it matches, the file is assumed to be
1296 interpreted by the interpreter matched by the second group of the
1297 regular expression. The mode is then determined as the mode
1298 associated with that interpreter in `interpreter-mode-alist'.
1299
1300 ** New function executable-make-buffer-file-executable-if-script-p is
1301 suitable as an after-save-hook as an alternative to `executable-chmod'.
1302
1303 ** The most preferred coding-system is now used to save a buffer if
1304 buffer-file-coding-system is `undecided' and it is safe for the buffer
1305 contents. (The most preferred is set by set-language-environment or
1306 by M-x prefer-coding-system.) Thus if you visit an ASCII file and
1307 insert a non-ASCII character from your current language environment,
1308 the file will be saved silently with the appropriate coding.
1309 Previously you would be prompted for a safe coding system.
1310
1311 ** The many obsolete language `setup-...-environment' commands have
1312 been removed -- use `set-language-environment'.
1313
1314 ** The new Custom option `keyboard-coding-system' specifies a coding
1315 system for keyboard input.
1316
1317 ** New variable `inhibit-iso-escape-detection' determines if Emacs'
1318 coding system detection algorithm should pay attention to ISO2022's
1319 escape sequences. If this variable is non-nil, the algorithm ignores
1320 such escape sequences. The default value is nil, and it is
1321 recommended not to change it except for the special case that you
1322 always want to read any escape code verbatim. If you just want to
1323 read a specific file without decoding escape codes, use C-x RET c
1324 (`universal-coding-system-argument'). For instance, C-x RET c latin-1
1325 RET C-x C-f filename RET.
1326
1327 ** Variable `default-korean-keyboard' is initialized properly from the
1328 environment variable `HANGUL_KEYBOARD_TYPE'.
1329
1330 ** New command M-x list-charset-chars reads a character set name and
1331 displays all characters in that character set.
1332
1333 ** M-x set-terminal-coding-system (C-x RET t) now allows CCL-based
1334 coding systems such as cpXXX and cyrillic-koi8.
1335
1336 ** Emacs now attempts to determine the initial language environment
1337 and preferred and locale coding systems systematically from the
1338 LC_ALL, LC_CTYPE, and LANG environment variables during startup.
1339
1340 ** New language environments `Polish', `Latin-8' and `Latin-9'.
1341 Latin-8 and Latin-9 correspond respectively to the ISO character sets
1342 8859-14 (Celtic) and 8859-15 (updated Latin-1, with the Euro sign).
1343 GNU Intlfonts doesn't support these yet but recent X releases have
1344 8859-15. See etc/INSTALL for information on obtaining extra fonts.
1345 There are new Leim input methods for Latin-8 and Latin-9 prefix (only)
1346 and Polish `slash'.
1347
1348 ** New language environments `Dutch' and `Spanish'.
1349 These new environments mainly select appropriate translations
1350 of the tutorial.
1351
1352 ** In Ethiopic language environment, special key bindings for
1353 function keys are changed as follows. This is to conform to "Emacs
1354 Lisp Coding Convention".
1355
1356 new command old-binding
1357 --- ------- -----------
1358 f3 ethio-fidel-to-sera-buffer f5
1359 S-f3 ethio-fidel-to-sera-region f5
1360 C-f3 ethio-fidel-to-sera-mail-or-marker f5
1361
1362 f4 ethio-sera-to-fidel-buffer unchanged
1363 S-f4 ethio-sera-to-fidel-region unchanged
1364 C-f4 ethio-sera-to-fidel-mail-or-marker unchanged
1365
1366 S-f5 ethio-toggle-punctuation f3
1367 S-f6 ethio-modify-vowel f6
1368 S-f7 ethio-replace-space f7
1369 S-f8 ethio-input-special-character f8
1370 S-f9 ethio-replace-space unchanged
1371 C-f9 ethio-toggle-space f2
1372
1373 ** There are new Leim input methods.
1374 New input methods "turkish-postfix", "turkish-alt-postfix",
1375 "greek-mizuochi", "TeX", and "greek-babel" are now part of the Leim
1376 package.
1377
1378 ** The rule of input method "slovak" is slightly changed. Now the
1379 rules for translating "q" and "Q" to "`" (backquote) are deleted, thus
1380 typing them inserts "q" and "Q" respectively. Rules for translating
1381 "=q", "+q", "=Q", and "+Q" to "`" are also deleted. Now, to input
1382 "`", you must type "=q".
1383
1384 ** When your terminal can't display characters from some of the ISO
1385 8859 character sets but can display Latin-1, you can display
1386 more-or-less mnemonic sequences of ASCII/Latin-1 characters instead of
1387 empty boxes (under a window system) or question marks (not under a
1388 window system). Customize the option `latin1-display' to turn this
1389 on.
1390
1391 ** M-; now calls comment-dwim which tries to do something clever based
1392 on the context. M-x kill-comment is now an alias to comment-kill,
1393 defined in newcomment.el. You can choose different styles of region
1394 commenting with the variable `comment-style'.
1395
1396 ** New user options `display-time-mail-face' and
1397 `display-time-use-mail-icon' control the appearance of mode-line mail
1398 indicator used by the display-time package. On a suitable display the
1399 indicator can be an icon and is mouse-sensitive.
1400
1401 ** On window-systems, additional space can be put between text lines
1402 on the display using several methods
1403
1404 - By setting frame parameter `line-spacing' to PIXELS. PIXELS must be
1405 a positive integer, and specifies that PIXELS number of pixels should
1406 be put below text lines on the affected frame or frames.
1407
1408 - By setting X resource `lineSpacing', class `LineSpacing'. This is
1409 equivalent to specifying the frame parameter.
1410
1411 - By specifying `--line-spacing=N' or `-lsp N' on the command line.
1412
1413 - By setting buffer-local variable `line-spacing'. The meaning is
1414 the same, but applies to the a particular buffer only.
1415
1416 ** The new command `clone-indirect-buffer' can be used to create
1417 an indirect buffer that is a twin copy of the current buffer. The
1418 command `clone-indirect-buffer-other-window', bound to C-x 4 c,
1419 does the same but displays the indirect buffer in another window.
1420
1421 ** New user options `backup-directory-alist' and
1422 `make-backup-file-name-function' control the placement of backups,
1423 typically in a single directory or in an invisible sub-directory.
1424
1425 ** New commands iso-iso2sgml and iso-sgml2iso convert between Latin-1
1426 characters and the corresponding SGML (HTML) entities.
1427
1428 ** New X resources recognized
1429
1430 *** The X resource `synchronous', class `Synchronous', specifies
1431 whether Emacs should run in synchronous mode. Synchronous mode
1432 is useful for debugging X problems.
1433
1434 Example:
1435
1436 emacs.synchronous: true
1437
1438 *** The X resource `visualClass, class `VisualClass', specifies the
1439 visual Emacs should use. The resource's value should be a string of
1440 the form `CLASS-DEPTH', where CLASS is the name of the visual class,
1441 and DEPTH is the requested color depth as a decimal number. Valid
1442 visual class names are
1443
1444 TrueColor
1445 PseudoColor
1446 DirectColor
1447 StaticColor
1448 GrayScale
1449 StaticGray
1450
1451 Visual class names specified as X resource are case-insensitive, i.e.
1452 `pseudocolor', `Pseudocolor' and `PseudoColor' all have the same
1453 meaning.
1454
1455 The program `xdpyinfo' can be used to list the visual classes
1456 supported on your display, and which depths they have. If
1457 `visualClass' is not specified, Emacs uses the display's default
1458 visual.
1459
1460 Example:
1461
1462 emacs.visualClass: TrueColor-8
1463
1464 *** The X resource `privateColormap', class `PrivateColormap',
1465 specifies that Emacs should use a private colormap if it is using the
1466 default visual, and that visual is of class PseudoColor. Recognized
1467 resource values are `true' or `on'.
1468
1469 Example:
1470
1471 emacs.privateColormap: true
1472
1473 ** Faces and frame parameters.
1474
1475 There are four new faces `scroll-bar', `border', `cursor' and `mouse'.
1476 Setting the frame parameters `scroll-bar-foreground' and
1477 `scroll-bar-background' sets foreground and background color of face
1478 `scroll-bar' and vice versa. Setting frame parameter `border-color'
1479 sets the background color of face `border' and vice versa. Likewise
1480 for frame parameters `cursor-color' and face `cursor', and frame
1481 parameter `mouse-color' and face `mouse'.
1482
1483 Changing frame parameter `font' sets font-related attributes of the
1484 `default' face and vice versa. Setting frame parameters
1485 `foreground-color' or `background-color' sets the colors of the
1486 `default' face and vice versa.
1487
1488 ** New face `menu'.
1489
1490 The face `menu' can be used to change colors and font of Emacs' menus.
1491
1492 ** New frame parameter `screen-gamma' for gamma correction.
1493
1494 The new frame parameter `screen-gamma' specifies gamma-correction for
1495 colors. Its value may be nil, the default, in which case no gamma
1496 correction occurs, or a number > 0, usually a float, that specifies
1497 the screen gamma of a frame's display.
1498
1499 PC monitors usually have a screen gamma of 2.2. smaller values result
1500 in darker colors. You might want to try a screen gamma of 1.5 for LCD
1501 color displays. The viewing gamma Emacs uses is 0.4545. (1/2.2).
1502
1503 The X resource name of this parameter is `screenGamma', class
1504 `ScreenGamma'.
1505
1506 ** Tabs and variable-width text.
1507
1508 Tabs are now displayed with stretch properties; the width of a tab is
1509 defined as a multiple of the normal character width of a frame, and is
1510 independent of the fonts used in the text where the tab appears.
1511 Thus, tabs can be used to line up text in different fonts.
1512
1513 ** Enhancements of the Lucid menu bar
1514
1515 *** The Lucid menu bar now supports the resource "margin".
1516
1517 emacs.pane.menubar.margin: 5
1518
1519 The default margin is 4 which makes the menu bar appear like the
1520 LessTif/Motif one.
1521
1522 *** Arrows that indicate sub-menus are now drawn with shadows, as in
1523 LessTif and Motif.
1524
1525 ** A block cursor can be drawn as wide as the glyph under it under X.
1526
1527 As an example: if a block cursor is over a tab character, it will be
1528 drawn as wide as that tab on the display. To do this, set
1529 `x-stretch-cursor' to a non-nil value.
1530
1531 ** Empty display lines at the end of a buffer may be marked with a
1532 bitmap (this is similar to the tilde displayed by vi and Less).
1533
1534 This behavior is activated by setting the buffer-local variable
1535 `indicate-empty-lines' to a non-nil value. The default value of this
1536 variable is found in `default-indicate-empty-lines'.
1537
1538 ** There is a new "aggressive" scrolling method.
1539
1540 When scrolling up because point is above the window start, if the
1541 value of the buffer-local variable `scroll-up-aggressively' is a
1542 number, Emacs chooses a new window start so that point ends up that
1543 fraction of the window's height from the top of the window.
1544
1545 When scrolling down because point is below the window end, if the
1546 value of the buffer-local variable `scroll-down-aggressively' is a
1547 number, Emacs chooses a new window start so that point ends up that
1548 fraction of the window's height from the bottom of the window.
1549
1550 ** You can now easily create new *Info* buffers using either
1551 M-x clone-buffer, C-u m <entry> RET or C-u g <entry> RET.
1552 M-x clone-buffer can also be used on *Help* and several other special
1553 buffers.
1554
1555 ** The command `Info-search' now uses a search history.
1556
1557 ** Listing buffers with M-x list-buffers (C-x C-b) now shows
1558 abbreviated file names. Abbreviations can be customized by changing
1559 `directory-abbrev-alist'.
1560
1561 ** A new variable, backup-by-copying-when-privileged-mismatch, gives
1562 the highest file uid for which backup-by-copying-when-mismatch will be
1563 forced on. The assumption is that uids less than or equal to this
1564 value are special uids (root, bin, daemon, etc.--not real system
1565 users) and that files owned by these users should not change ownership,
1566 even if your system policy allows users other than root to edit them.
1567
1568 The default is 200; set the variable to nil to disable the feature.
1569
1570 ** The rectangle commands now avoid inserting undesirable spaces,
1571 notably at the end of lines.
1572
1573 All these functions have been rewritten to avoid inserting unwanted
1574 spaces, and an optional prefix now allows them to behave the old way.
1575
1576 ** The function `replace-rectangle' is an alias for `string-rectangle'.
1577
1578 ** The new command M-x string-insert-rectangle is like `string-rectangle',
1579 but inserts text instead of replacing it.
1580
1581 ** The new command M-x query-replace-regexp-eval acts like
1582 query-replace-regexp, but takes a Lisp expression which is evaluated
1583 after each match to get the replacement text.
1584
1585 ** M-x query-replace recognizes a new command `e' (or `E') that lets
1586 you edit the replacement string.
1587
1588 ** The new command mail-abbrev-complete-alias, bound to `M-TAB'
1589 (if you load the library `mailabbrev'), lets you complete mail aliases
1590 in the text, analogous to lisp-complete-symbol.
1591
1592 ** The variable `echo-keystrokes' may now have a floating point value.
1593
1594 ** If your init file is compiled (.emacs.elc), `user-init-file' is set
1595 to the source name (.emacs.el), if that exists, after loading it.
1596
1597 ** The help string specified for a menu-item whose definition contains
1598 the property `:help HELP' is now displayed under X, on MS-Windows, and
1599 MS-DOS, either in the echo area or with tooltips. Many standard menus
1600 displayed by Emacs now have help strings.
1601
1602 --
1603 ** New user option `read-mail-command' specifies a command to use to
1604 read mail from the menu etc.
1605
1606 ** The environment variable `EMACSLOCKDIR' is no longer used on MS-Windows.
1607 This environment variable was used when creating lock files. Emacs on
1608 MS-Windows does not use this variable anymore. This change was made
1609 before Emacs 21.1, but wasn't documented until now.
1610
1611 ** Highlighting of mouse-sensitive regions is now supported in the
1612 MS-DOS version of Emacs.
1613
1614 ** The new command `msdos-set-mouse-buttons' forces the MS-DOS version
1615 of Emacs to behave as if the mouse had a specified number of buttons.
1616 This comes handy with mice that don't report their number of buttons
1617 correctly. One example is the wheeled mice, which report 3 buttons,
1618 but clicks on the middle button are not passed to the MS-DOS version
1619 of Emacs.
1620
1621 ** Customize changes
1622
1623 *** Customize now supports comments about customized items. Use the
1624 `State' menu to add comments, or give a prefix argument to
1625 M-x customize-set-variable or M-x customize-set-value. Note that
1626 customization comments will cause the customizations to fail in
1627 earlier versions of Emacs.
1628
1629 *** The new option `custom-buffer-done-function' says whether to kill
1630 Custom buffers when you've done with them or just bury them (the
1631 default).
1632
1633 *** If Emacs was invoked with the `-q' or `--no-init-file' options, it
1634 does not allow you to save customizations in your `~/.emacs' init
1635 file. This is because saving customizations from such a session would
1636 wipe out all the other customizationss you might have on your init
1637 file.
1638
1639 ** If Emacs was invoked with the `-q' or `--no-init-file' options, it
1640 does not save disabled and enabled commands for future sessions, to
1641 avoid overwriting existing customizations of this kind that are
1642 already in your init file.
1643
1644 ** New features in evaluation commands
1645
1646 *** The commands to evaluate Lisp expressions, such as C-M-x in Lisp
1647 modes, C-j in Lisp Interaction mode, and M-:, now bind the variables
1648 print-level, print-length, and debug-on-error based on the new
1649 customizable variables eval-expression-print-level,
1650 eval-expression-print-length, and eval-expression-debug-on-error.
1651
1652 The default values for the first two of these variables are 12 and 4
1653 respectively, which means that `eval-expression' now prints at most
1654 the first 12 members of a list and at most 4 nesting levels deep (if
1655 the list is longer or deeper than that, an ellipsis `...' is
1656 printed).
1657
1658 <RET> or <mouse-2> on the printed text toggles between an abbreviated
1659 printed representation and an unabbreviated one.
1660
1661 The default value of eval-expression-debug-on-error is t, so any error
1662 during evaluation produces a backtrace.
1663
1664 *** The function `eval-defun' (C-M-x) now loads Edebug and instruments
1665 code when called with a prefix argument.
1666
1667 ** CC mode changes.
1668
1669 Note: This release contains changes that might not be compatible with
1670 current user setups (although it's believed that these
1671 incompatibilities will only show in very uncommon circumstances).
1672 However, since the impact is uncertain, these changes may be rolled
1673 back depending on user feedback. Therefore there's no forward
1674 compatibility guarantee wrt the new features introduced in this
1675 release.
1676
1677 *** The hardcoded switch to "java" style in Java mode is gone.
1678 CC Mode used to automatically set the style to "java" when Java mode
1679 is entered. This has now been removed since it caused too much
1680 confusion.
1681
1682 However, to keep backward compatibility to a certain extent, the
1683 default value for c-default-style now specifies the "java" style for
1684 java-mode, but "gnu" for all other modes (as before). So you won't
1685 notice the change if you haven't touched that variable.
1686
1687 *** New cleanups, space-before-funcall and compact-empty-funcall.
1688 Two new cleanups have been added to c-cleanup-list:
1689
1690 space-before-funcall causes a space to be inserted before the opening
1691 parenthesis of a function call, which gives the style "foo (bar)".
1692
1693 compact-empty-funcall causes any space before a function call opening
1694 parenthesis to be removed if there are no arguments to the function.
1695 It's typically useful together with space-before-funcall to get the
1696 style "foo (bar)" and "foo()".
1697
1698 *** Some keywords now automatically trigger reindentation.
1699 Keywords like "else", "while", "catch" and "finally" have been made
1700 "electric" to make them reindent automatically when they continue an
1701 earlier statement. An example:
1702
1703 for (i = 0; i < 17; i++)
1704 if (a[i])
1705 res += a[i]->offset;
1706 else
1707
1708 Here, the "else" should be indented like the preceding "if", since it
1709 continues that statement. CC Mode will automatically reindent it after
1710 the "else" has been typed in full, since it's not until then it's
1711 possible to decide whether it's a new statement or a continuation of
1712 the preceding "if".
1713
1714 CC Mode uses Abbrev mode to achieve this, which is therefore turned on
1715 by default.
1716
1717 *** M-a and M-e now moves by sentence in multiline strings.
1718 Previously these two keys only moved by sentence in comments, which
1719 meant that sentence movement didn't work in strings containing
1720 documentation or other natural language text.
1721
1722 The reason it's only activated in multiline strings (i.e. strings that
1723 contain a newline, even when escaped by a '\') is to avoid stopping in
1724 the short strings that often reside inside statements. Multiline
1725 strings almost always contain text in a natural language, as opposed
1726 to other strings that typically contain format specifications,
1727 commands, etc. Also, it's not that bothersome that M-a and M-e misses
1728 sentences in single line strings, since they're short anyway.
1729
1730 *** Support for autodoc comments in Pike mode.
1731 Autodoc comments for Pike are used to extract documentation from the
1732 source, like Javadoc in Java. Pike mode now recognize this markup in
1733 comment prefixes and paragraph starts.
1734
1735 *** The comment prefix regexps on c-comment-prefix may be mode specific.
1736 When c-comment-prefix is an association list, it specifies the comment
1737 line prefix on a per-mode basis, like c-default-style does. This
1738 change came about to support the special autodoc comment prefix in
1739 Pike mode only.
1740
1741 *** Better handling of syntactic errors.
1742 The recovery after unbalanced parens earlier in the buffer has been
1743 improved; CC Mode now reports them by dinging and giving a message
1744 stating the offending line, but still recovers and indent the
1745 following lines in a sane way (most of the time). An "else" with no
1746 matching "if" is handled similarly. If an error is discovered while
1747 indenting a region, the whole region is still indented and the error
1748 is reported afterwards.
1749
1750 *** Lineup functions may now return absolute columns.
1751 A lineup function can give an absolute column to indent the line to by
1752 returning a vector with the desired column as the first element.
1753
1754 *** More robust and warning-free byte compilation.
1755 Although this is strictly not a user visible change (well, depending
1756 on the view of a user), it's still worth mentioning that CC Mode now
1757 can be compiled in the standard ways without causing trouble. Some
1758 code have also been moved between the subpackages to enhance the
1759 modularity somewhat. Thanks to Martin Buchholz for doing the
1760 groundwork.
1761
1762 *** c-style-variables-are-local-p now defaults to t.
1763 This is an incompatible change that has been made to make the behavior
1764 of the style system wrt global variable settings less confusing for
1765 non-advanced users. If you know what this variable does you might
1766 want to set it to nil in your .emacs, otherwise you probably don't
1767 have to bother.
1768
1769 Defaulting c-style-variables-are-local-p to t avoids the confusing
1770 situation that occurs when a user sets some style variables globally
1771 and edits both a Java and a non-Java file in the same Emacs session.
1772 If the style variables aren't buffer local in this case, loading of
1773 the second file will cause the default style (either "gnu" or "java"
1774 by default) to override the global settings made by the user.
1775
1776 *** New initialization procedure for the style system.
1777 When the initial style for a buffer is determined by CC Mode (from the
1778 variable c-default-style), the global values of style variables now
1779 take precedence over the values specified by the chosen style. This
1780 is different than the old behavior: previously, the style-specific
1781 settings would override the global settings. This change makes it
1782 possible to do simple configuration in the intuitive way with
1783 Customize or with setq lines in one's .emacs file.
1784
1785 By default, the global value of every style variable is the new
1786 special symbol set-from-style, which causes the value to be taken from
1787 the style system. This means that in effect, only an explicit setting
1788 of a style variable will cause the "overriding" behavior described
1789 above.
1790
1791 Also note that global settings override style-specific settings *only*
1792 when the initial style of a buffer is chosen by a CC Mode major mode
1793 function. When a style is chosen in other ways --- for example, by a
1794 call like (c-set-style "gnu") in a hook, or via M-x c-set-style ---
1795 then the style-specific values take precedence over any global style
1796 values. In Lisp terms, global values override style-specific values
1797 only when the new second argument to c-set-style is non-nil; see the
1798 function documentation for more info.
1799
1800 The purpose of these changes is to make it easier for users,
1801 especially novice users, to do simple customizations with Customize or
1802 with setq in their .emacs files. On the other hand, the new system is
1803 intended to be compatible with advanced users' customizations as well,
1804 such as those that choose styles in hooks or whatnot. This new system
1805 is believed to be almost entirely compatible with current
1806 configurations, in spite of the changed precedence between style and
1807 global variable settings when a buffer's default style is set.
1808
1809 (Thanks to Eric Eide for clarifying this explanation a bit.)
1810
1811 **** c-offsets-alist is now a customizable variable.
1812 This became possible as a result of the new initialization behavior.
1813
1814 This variable is treated slightly differently from the other style
1815 variables; instead of using the symbol set-from-style, it will be
1816 completed with the syntactic symbols it doesn't already contain when
1817 the style is first initialized. This means it now defaults to the
1818 empty list to make all syntactic elements get their values from the
1819 style system.
1820
1821 **** Compatibility variable to restore the old behavior.
1822 In case your configuration doesn't work with this change, you can set
1823 c-old-style-variable-behavior to non-nil to get the old behavior back
1824 as far as possible.
1825
1826 *** Improvements to line breaking and text filling.
1827 CC Mode now handles this more intelligently and seamlessly wrt the
1828 surrounding code, especially inside comments. For details see the new
1829 chapter about this in the manual.
1830
1831 **** New variable to recognize comment line prefix decorations.
1832 The variable c-comment-prefix-regexp has been added to properly
1833 recognize the line prefix in both block and line comments. It's
1834 primarily used to initialize the various paragraph recognition and
1835 adaptive filling variables that the text handling functions uses.
1836
1837 **** New variable c-block-comment-prefix.
1838 This is a generalization of the now obsolete variable
1839 c-comment-continuation-stars to handle arbitrary strings.
1840
1841 **** CC Mode now uses adaptive fill mode.
1842 This to make it adapt better to the paragraph style inside comments.
1843
1844 It's also possible to use other adaptive filling packages inside CC
1845 Mode, notably Kyle E. Jones' Filladapt mode (http://wonderworks.com/).
1846 A new convenience function c-setup-filladapt sets up Filladapt for use
1847 inside CC Mode.
1848
1849 Note though that the 2.12 version of Filladapt lacks a feature that
1850 causes it to work suboptimally when c-comment-prefix-regexp can match
1851 the empty string (which it commonly does). A patch for that is
1852 available from the CC Mode web site (http://www.python.org/emacs/
1853 cc-mode/).
1854
1855 **** The variables `c-hanging-comment-starter-p' and
1856 `c-hanging-comment-ender-p', which controlled how comment starters and
1857 enders were filled, are not used anymore. The new version of the
1858 function `c-fill-paragraph' keeps the comment starters and enders as
1859 they were before the filling.
1860
1861 **** It's now possible to selectively turn off auto filling.
1862 The variable c-ignore-auto-fill is used to ignore auto fill mode in
1863 specific contexts, e.g. in preprocessor directives and in string
1864 literals.
1865
1866 **** New context sensitive line break function c-context-line-break.
1867 It works like newline-and-indent in normal code, and adapts the line
1868 prefix according to the comment style when used inside comments. If
1869 you're normally using newline-and-indent, you might want to switch to
1870 this function.
1871
1872 *** Fixes to IDL mode.
1873 It now does a better job in recognizing only the constructs relevant
1874 to IDL. E.g. it no longer matches "class" as the beginning of a
1875 struct block, but it does match the CORBA 2.3 "valuetype" keyword.
1876 Thanks to Eric Eide.
1877
1878 *** Improvements to the Whitesmith style.
1879 It now keeps the style consistently on all levels and both when
1880 opening braces hangs and when they don't.
1881
1882 **** New lineup function c-lineup-whitesmith-in-block.
1883
1884 *** New lineup functions c-lineup-template-args and c-indent-multi-line-block.
1885 See their docstrings for details. c-lineup-template-args does a
1886 better job of tracking the brackets used as parens in C++ templates,
1887 and is used by default to line up continued template arguments.
1888
1889 *** c-lineup-comment now preserves alignment with a comment on the
1890 previous line. It used to instead preserve comments that started in
1891 the column specified by comment-column.
1892
1893 *** c-lineup-C-comments handles "free form" text comments.
1894 In comments with a long delimiter line at the start, the indentation
1895 is kept unchanged for lines that start with an empty comment line
1896 prefix. This is intended for the type of large block comments that
1897 contain documentation with its own formatting. In these you normally
1898 don't want CC Mode to change the indentation.
1899
1900 *** The `c' syntactic symbol is now relative to the comment start
1901 instead of the previous line, to make integers usable as lineup
1902 arguments.
1903
1904 *** All lineup functions have gotten docstrings.
1905
1906 *** More preprocessor directive movement functions.
1907 c-down-conditional does the reverse of c-up-conditional.
1908 c-up-conditional-with-else and c-down-conditional-with-else are
1909 variants of these that also stops at "#else" lines (suggested by Don
1910 Provan).
1911
1912 *** Minor improvements to many movement functions in tricky situations.
1913
1914 ** Dired changes
1915
1916 *** New variable `dired-recursive-deletes' determines if the delete
1917 command will delete non-empty directories recursively. The default
1918 is, delete only empty directories.
1919
1920 *** New variable `dired-recursive-copies' determines if the copy
1921 command will copy directories recursively. The default is, do not
1922 copy directories recursively.
1923
1924 *** In command `dired-do-shell-command' (usually bound to `!') a `?'
1925 in the shell command has a special meaning similar to `*', but with
1926 the difference that the command will be run on each file individually.
1927
1928 *** The new command `dired-find-alternate-file' (usually bound to `a')
1929 replaces the Dired buffer with the buffer for an alternate file or
1930 directory.
1931
1932 *** The new command `dired-show-file-type' (usually bound to `y') shows
1933 a message in the echo area describing what type of file the point is on.
1934 This command invokes the external program `file' do its work, and so
1935 will only work on systems with that program, and will be only as
1936 accurate or inaccurate as it is.
1937
1938 *** Dired now properly handles undo changes of adding/removing `-R'
1939 from ls switches.
1940
1941 *** Dired commands that prompt for a destination file now allow the use
1942 of the `M-n' command in the minibuffer to insert the source filename,
1943 which the user can then edit. This only works if there is a single
1944 source file, not when operating on multiple marked files.
1945
1946 ** Gnus changes.
1947
1948 The Gnus NEWS entries are short, but they reflect sweeping changes in
1949 four areas: Article display treatment, MIME treatment,
1950 internationalization and mail-fetching.
1951
1952 *** The mail-fetching functions have changed. See the manual for the
1953 many details. In particular, all procmail fetching variables are gone.
1954
1955 If you used procmail like in
1956
1957 (setq nnmail-use-procmail t)
1958 (setq nnmail-spool-file 'procmail)
1959 (setq nnmail-procmail-directory "~/mail/incoming/")
1960 (setq nnmail-procmail-suffix "\\.in")
1961
1962 this now has changed to
1963
1964 (setq mail-sources
1965 '((directory :path "~/mail/incoming/"
1966 :suffix ".in")))
1967
1968 More information is available in the info doc at Select Methods ->
1969 Getting Mail -> Mail Sources
1970
1971 *** Gnus is now a MIME-capable reader. This affects many parts of
1972 Gnus, and adds a slew of new commands. See the manual for details.
1973 Separate MIME packages like RMIME, mime-compose etc., will probably no
1974 longer work; remove them and use the native facilities.
1975
1976 The FLIM/SEMI package still works with Emacs 21, but if you want to
1977 use the native facilities, you must remove any mailcap.el[c] that was
1978 installed by FLIM/SEMI version 1.13 or earlier.
1979
1980 *** Gnus has also been multilingualized. This also affects too many
1981 parts of Gnus to summarize here, and adds many new variables. There
1982 are built-in facilities equivalent to those of gnus-mule.el, which is
1983 now just a compatibility layer.
1984
1985 *** gnus-mule.el is now just a compatibility layer over the built-in
1986 Gnus facilities.
1987
1988 *** gnus-auto-select-first can now be a function to be
1989 called to position point.
1990
1991 *** The user can now decide which extra headers should be included in
1992 summary buffers and NOV files.
1993
1994 *** `gnus-article-display-hook' has been removed. Instead, a number
1995 of variables starting with `gnus-treat-' have been added.
1996
1997 *** The Gnus posting styles have been redone again and now work in a
1998 subtly different manner.
1999
2000 *** New web-based backends have been added: nnslashdot, nnwarchive
2001 and nnultimate. nnweb has been revamped, again, to keep up with
2002 ever-changing layouts.
2003
2004 *** Gnus can now read IMAP mail via nnimap.
2005
2006 *** There is image support of various kinds and some sound support.
2007
2008 ** Changes in Texinfo mode.
2009
2010 *** A couple of new key bindings have been added for inserting Texinfo
2011 macros
2012
2013 Key binding Macro
2014 -------------------------
2015 C-c C-c C-s @strong
2016 C-c C-c C-e @emph
2017 C-c C-c u @uref
2018 C-c C-c q @quotation
2019 C-c C-c m @email
2020 C-c C-o @<block> ... @end <block>
2021 M-RET @item
2022
2023 *** The " key now inserts either " or `` or '' depending on context.
2024
2025 ** Changes in Outline mode.
2026
2027 There is now support for Imenu to index headings. A new command
2028 `outline-headers-as-kill' copies the visible headings in the region to
2029 the kill ring, e.g. to produce a table of contents.
2030
2031 ** Changes to Emacs Server
2032
2033 *** The new option `server-kill-new-buffers' specifies what to do
2034 with buffers when done with them. If non-nil, the default, buffers
2035 are killed, unless they were already present before visiting them with
2036 Emacs Server. If nil, `server-temp-file-regexp' specifies which
2037 buffers to kill, as before.
2038
2039 Please note that only buffers are killed that still have a client,
2040 i.e. buffers visited with `emacsclient --no-wait' are never killed in
2041 this way.
2042
2043 ** Both emacsclient and Emacs itself now accept command line options
2044 of the form +LINE:COLUMN in addition to +LINE.
2045
2046 ** Changes to Show Paren mode.
2047
2048 *** Overlays used by Show Paren mode now use a priority property.
2049 The new user option show-paren-priority specifies the priority to
2050 use. Default is 1000.
2051
2052 ** New command M-x check-parens can be used to find unbalanced paren
2053 groups and strings in buffers in Lisp mode (or other modes).
2054
2055 ** Changes to hideshow.el
2056
2057 *** Generalized block selection and traversal
2058
2059 A block is now recognized by its start and end regexps (both strings),
2060 and an integer specifying which sub-expression in the start regexp
2061 serves as the place where a `forward-sexp'-like function can operate.
2062 See the documentation of variable `hs-special-modes-alist'.
2063
2064 *** During incremental search, if Hideshow minor mode is active,
2065 hidden blocks are temporarily shown. The variable `hs-headline' can
2066 be used in the mode line format to show the line at the beginning of
2067 the open block.
2068
2069 *** User option `hs-hide-all-non-comment-function' specifies a
2070 function to be called at each top-level block beginning, instead of
2071 the normal block-hiding function.
2072
2073 *** The command `hs-show-region' has been removed.
2074
2075 *** The key bindings have changed to fit the Emacs conventions,
2076 roughly imitating those of Outline minor mode. Notably, the prefix
2077 for all bindings is now `C-c @'. For details, see the documentation
2078 for `hs-minor-mode'.
2079
2080 *** The variable `hs-show-hidden-short-form' has been removed, and
2081 hideshow.el now always behaves as if this variable were set to t.
2082
2083 ** Changes to Change Log mode and Add-Log functions
2084
2085 *** If you invoke `add-change-log-entry' from a backup file, it makes
2086 an entry appropriate for the file's parent. This is useful for making
2087 log entries by comparing a version with deleted functions.
2088
2089 **** New command M-x change-log-merge merges another log into the
2090 current buffer.
2091
2092 *** New command M-x change-log-redate fixes any old-style date entries
2093 in a log file.
2094
2095 *** Change Log mode now adds a file's version number to change log
2096 entries if user-option `change-log-version-info-enabled' is non-nil.
2097 Unless the file is under version control the search for a file's
2098 version number is performed based on regular expressions from
2099 `change-log-version-number-regexp-list' which can be customized.
2100 Version numbers are only found in the first 10 percent of a file.
2101
2102 *** Change Log mode now defines its own faces for font-lock highlighting.
2103
2104 ** Changes to cmuscheme
2105
2106 *** The user-option `scheme-program-name' has been renamed
2107 `cmuscheme-program-name' due to conflicts with xscheme.el.
2108
2109 ** Changes in Font Lock
2110
2111 *** The new function `font-lock-remove-keywords' can be used to remove
2112 font-lock keywords from the current buffer or from a specific major mode.
2113
2114 *** Multi-line patterns are now supported. Modes using this, should
2115 set font-lock-multiline to t in their font-lock-defaults.
2116
2117 *** `font-lock-syntactic-face-function' allows major-modes to choose
2118 the face used for each string/comment.
2119
2120 *** A new standard face `font-lock-doc-face'.
2121 Meant for Lisp docstrings, Javadoc comments and other "documentation in code".
2122
2123 ** Changes to Shell mode
2124
2125 *** The `shell' command now accepts an optional argument to specify the buffer
2126 to use, which defaults to "*shell*". When used interactively, a
2127 non-default buffer may be specified by giving the `shell' command a
2128 prefix argument (causing it to prompt for the buffer name).
2129
2130 ** Comint (subshell) changes
2131
2132 These changes generally affect all modes derived from comint mode, which
2133 include shell-mode, gdb-mode, scheme-interaction-mode, etc.
2134
2135 *** Comint now by default interprets some carriage-control characters.
2136 Comint now removes CRs from CR LF sequences, and treats single CRs and
2137 BSs in the output in a way similar to a terminal (by deleting to the
2138 beginning of the line, or deleting the previous character,
2139 respectively). This is achieved by adding `comint-carriage-motion' to
2140 the `comint-output-filter-functions' hook by default.
2141
2142 *** By default, comint no longer uses the variable `comint-prompt-regexp'
2143 to distinguish prompts from user-input. Instead, it notices which
2144 parts of the text were output by the process, and which entered by the
2145 user, and attaches `field' properties to allow emacs commands to use
2146 this information. Common movement commands, notably beginning-of-line,
2147 respect field boundaries in a fairly natural manner. To disable this
2148 feature, and use the old behavior, customize the user option
2149 `comint-use-prompt-regexp-instead-of-fields'.
2150
2151 *** Comint now includes new features to send commands to running processes
2152 and redirect the output to a designated buffer or buffers.
2153
2154 *** The command M-x comint-redirect-send-command reads a command and
2155 buffer name from the mini-buffer. The command is sent to the current
2156 buffer's process, and its output is inserted into the specified buffer.
2157
2158 The command M-x comint-redirect-send-command-to-process acts like
2159 M-x comint-redirect-send-command but additionally reads the name of
2160 the buffer whose process should be used from the mini-buffer.
2161
2162 *** Packages based on comint now highlight user input and program prompts,
2163 and support choosing previous input with mouse-2. To control these features,
2164 see the user-options `comint-highlight-input' and `comint-highlight-prompt'.
2165
2166 *** The new command `comint-write-output' (usually bound to `C-c C-s')
2167 saves the output from the most recent command to a file. With a prefix
2168 argument, it appends to the file.
2169
2170 *** The command `comint-kill-output' has been renamed `comint-delete-output'
2171 (usually bound to `C-c C-o'); the old name is aliased to it for
2172 compatibility.
2173
2174 *** The new function `comint-add-to-input-history' adds commands to the input
2175 ring (history).
2176
2177 *** The new variable `comint-input-history-ignore' is a regexp for
2178 identifying history lines that should be ignored, like tcsh time-stamp
2179 strings, starting with a `#'. The default value of this variable is "^#".
2180
2181 ** Changes to Rmail mode
2182
2183 *** The new user-option rmail-user-mail-address-regexp can be
2184 set to fine tune the identification of the correspondent when
2185 receiving new mail. If it matches the address of the sender, the
2186 recipient is taken as correspondent of a mail. If nil, the default,
2187 `user-login-name' and `user-mail-address' are used to exclude yourself
2188 as correspondent.
2189
2190 Usually you don't have to set this variable, except if you collect
2191 mails sent by you under different user names. Then it should be a
2192 regexp matching your mail addresses.
2193
2194 *** The new user-option rmail-confirm-expunge controls whether and how
2195 to ask for confirmation before expunging deleted messages from an
2196 Rmail file. You can choose between no confirmation, confirmation
2197 with y-or-n-p, or confirmation with yes-or-no-p. Default is to ask
2198 for confirmation with yes-or-no-p.
2199
2200 *** RET is now bound in the Rmail summary to rmail-summary-goto-msg,
2201 like `j'.
2202
2203 *** There is a new user option `rmail-digest-end-regexps' that
2204 specifies the regular expressions to detect the line that ends a
2205 digest message.
2206
2207 *** The new user option `rmail-automatic-folder-directives' specifies
2208 in which folder to put messages automatically.
2209
2210 *** The new function `rmail-redecode-body' allows to fix a message
2211 with non-ASCII characters if Emacs happens to decode it incorrectly
2212 due to missing or malformed "charset=" header.
2213
2214 ** The new user-option `mail-envelope-from' can be used to specify
2215 an envelope-from address different from user-mail-address.
2216
2217 ** The variable mail-specify-envelope-from controls whether to
2218 use the -f option when sending mail.
2219
2220 ** The Rmail command `o' (`rmail-output-to-rmail-file') now writes the
2221 current message in the internal `emacs-mule' encoding, rather than in
2222 the encoding taken from the variable `buffer-file-coding-system'.
2223 This allows to save messages whose characters cannot be safely encoded
2224 by the buffer's coding system, and makes sure the message will be
2225 displayed correctly when you later visit the target Rmail file.
2226
2227 If you want your Rmail files be encoded in a specific coding system
2228 other than `emacs-mule', you can customize the variable
2229 `rmail-file-coding-system' to set its value to that coding system.
2230
2231 ** Changes to TeX mode
2232
2233 *** The default mode has been changed from `plain-tex-mode' to
2234 `latex-mode'.
2235
2236 *** latex-mode now has a simple indentation algorithm.
2237
2238 *** M-f and M-p jump around \begin...\end pairs.
2239
2240 *** Added support for outline-minor-mode.
2241
2242 ** Changes to RefTeX mode
2243
2244 *** RefTeX has new support for index generation. Index entries can be
2245 created with `C-c <', with completion available on index keys.
2246 Pressing `C-c /' indexes the word at the cursor with a default
2247 macro. `C-c >' compiles all index entries into an alphabetically
2248 sorted *Index* buffer which looks like the final index. Entries
2249 can be edited from that buffer.
2250
2251 *** Label and citation key selection now allow to select several
2252 items and reference them together (use `m' to mark items, `a' or
2253 `A' to use all marked entries).
2254
2255 *** reftex.el has been split into a number of smaller files to reduce
2256 memory use when only a part of RefTeX is being used.
2257
2258 *** a new command `reftex-view-crossref-from-bibtex' (bound to `C-c &'
2259 in BibTeX-mode) can be called in a BibTeX database buffer in order
2260 to show locations in LaTeX documents where a particular entry has
2261 been cited.
2262
2263 ** Emacs Lisp mode now allows multiple levels of outline headings.
2264 The level of a heading is determined from the number of leading
2265 semicolons in a heading line. Toplevel forms starting with a `('
2266 in column 1 are always made leaves.
2267
2268 ** The M-x time-stamp command (most commonly used on write-file-hooks)
2269 has the following new features:
2270
2271 *** The patterns for finding the time stamp and for updating a pattern
2272 may match text spanning multiple lines. For example, some people like
2273 to have the filename and date on separate lines. The new variable
2274 time-stamp-inserts-lines controls the matching for multi-line patterns.
2275
2276 *** More than one time stamp can be updated in the same file. This
2277 feature is useful if you need separate time stamps in a program source
2278 file to both include in formatted documentation and insert in the
2279 compiled binary. The same time-stamp will be written at each matching
2280 pattern. The variable time-stamp-count enables this new feature; it
2281 defaults to 1.
2282
2283 ** Partial Completion mode now completes environment variables in
2284 file names.
2285
2286 ** Ispell changes
2287
2288 *** The command `ispell' now spell-checks a region if
2289 transient-mark-mode is on, and the mark is active. Otherwise it
2290 spell-checks the current buffer.
2291
2292 *** Support for synchronous subprocesses - DOS/Windoze - has been
2293 added.
2294
2295 *** An "alignment error" bug was fixed when a manual spelling
2296 correction is made and re-checked.
2297
2298 *** An Italian, Portuguese, and Slovak dictionary definition has been added.
2299
2300 *** Region skipping performance has been vastly improved in some
2301 cases.
2302
2303 *** Spell checking HTML buffers has been improved and isn't so strict
2304 on syntax errors.
2305
2306 *** The buffer-local words are now always placed on a new line at the
2307 end of the buffer.
2308
2309 *** Spell checking now works in the MS-DOS version of Emacs.
2310
2311 ** Makefile mode changes
2312
2313 *** The mode now uses the abbrev table `makefile-mode-abbrev-table'.
2314
2315 *** Conditionals and include statements are now highlighted when
2316 Fontlock mode is active.
2317
2318 ** Isearch changes
2319
2320 *** Isearch now puts a call to `isearch-resume' in the command history,
2321 so that searches can be resumed.
2322
2323 *** In Isearch mode, C-M-s and C-M-r are now bound like C-s and C-r,
2324 respectively, i.e. you can repeat a regexp isearch with the same keys
2325 that started the search.
2326
2327 *** In Isearch mode, mouse-2 in the echo area now yanks the current
2328 selection into the search string rather than giving an error.
2329
2330 *** There is a new lazy highlighting feature in incremental search.
2331
2332 Lazy highlighting is switched on/off by customizing variable
2333 `isearch-lazy-highlight'. When active, all matches for the current
2334 search string are highlighted. The current match is highlighted as
2335 before using face `isearch' or `region'. All other matches are
2336 highlighted using face `isearch-lazy-highlight-face' which defaults to
2337 `secondary-selection'.
2338
2339 The extra highlighting makes it easier to anticipate where the cursor
2340 will end up each time you press C-s or C-r to repeat a pending search.
2341 Highlighting of these additional matches happens in a deferred fashion
2342 using "idle timers," so the cycles needed do not rob isearch of its
2343 usual snappy response.
2344
2345 If `isearch-lazy-highlight-cleanup' is set to t, highlights for
2346 matches are automatically cleared when you end the search. If it is
2347 set to nil, you can remove the highlights manually with `M-x
2348 isearch-lazy-highlight-cleanup'.
2349
2350 ** VC Changes
2351
2352 VC has been overhauled internally. It is now modular, making it
2353 easier to plug-in arbitrary version control backends. (See Lisp
2354 Changes for details on the new structure.) As a result, the mechanism
2355 to enable and disable support for particular version systems has
2356 changed: everything is now controlled by the new variable
2357 `vc-handled-backends'. Its value is a list of symbols that identify
2358 version systems; the default is '(RCS CVS SCCS). When finding a file,
2359 each of the backends in that list is tried in order to see whether the
2360 file is registered in that backend.
2361
2362 When registering a new file, VC first tries each of the listed
2363 backends to see if any of them considers itself "responsible" for the
2364 directory of the file (e.g. because a corresponding subdirectory for
2365 master files exists). If none of the backends is responsible, then
2366 the first backend in the list that could register the file is chosen.
2367 As a consequence, the variable `vc-default-back-end' is now obsolete.
2368
2369 The old variable `vc-master-templates' is also obsolete, although VC
2370 still supports it for backward compatibility. To define templates for
2371 RCS or SCCS, you should rather use the new variables
2372 vc-{rcs,sccs}-master-templates. (There is no such feature under CVS
2373 where it doesn't make sense.)
2374
2375 The variables `vc-ignore-vc-files' and `vc-handle-cvs' are also
2376 obsolete now, you must set `vc-handled-backends' to nil or exclude
2377 `CVS' from the list, respectively, to achieve their effect now.
2378
2379 *** General Changes
2380
2381 The variable `vc-checkout-carefully' is obsolete: the corresponding
2382 checks are always done now.
2383
2384 VC Dired buffers are now kept up-to-date during all version control
2385 operations.
2386
2387 `vc-diff' output is now displayed in `diff-mode'.
2388 `vc-print-log' uses `log-view-mode'.
2389 `vc-log-mode' (used for *VC-Log*) has been replaced by `log-edit-mode'.
2390
2391 The command C-x v m (vc-merge) now accepts an empty argument as the
2392 first revision number. This means that any recent changes on the
2393 current branch should be picked up from the repository and merged into
2394 the working file (``merge news'').
2395
2396 The commands C-x v s (vc-create-snapshot) and C-x v r
2397 (vc-retrieve-snapshot) now ask for a directory name from which to work
2398 downwards.
2399
2400 *** Multiple Backends
2401
2402 VC now lets you register files in more than one backend. This is
2403 useful, for example, if you are working with a slow remote CVS
2404 repository. You can then use RCS for local editing, and occasionally
2405 commit your changes back to CVS, or pick up changes from CVS into your
2406 local RCS archives.
2407
2408 To make this work, the ``more local'' backend (RCS in our example)
2409 should come first in `vc-handled-backends', and the ``more remote''
2410 backend (CVS) should come later. (The default value of
2411 `vc-handled-backends' already has it that way.)
2412
2413 You can then commit changes to another backend (say, RCS), by typing
2414 C-u C-x v v RCS RET (i.e. vc-next-action now accepts a backend name as
2415 a revision number). VC registers the file in the more local backend
2416 if that hasn't already happened, and commits to a branch based on the
2417 current revision number from the more remote backend.
2418
2419 If a file is registered in multiple backends, you can switch to
2420 another one using C-x v b (vc-switch-backend). This does not change
2421 any files, it only changes VC's perspective on the file. Use this to
2422 pick up changes from CVS while working under RCS locally.
2423
2424 After you are done with your local RCS editing, you can commit your
2425 changes back to CVS using C-u C-x v v CVS RET. In this case, the
2426 local RCS archive is removed after the commit, and the log entry
2427 buffer is initialized to contain the entire RCS change log of the file.
2428
2429 *** Changes for CVS
2430
2431 There is a new user option, `vc-cvs-stay-local'. If it is `t' (the
2432 default), then VC avoids network queries for files registered in
2433 remote repositories. The state of such files is then only determined
2434 by heuristics and past information. `vc-cvs-stay-local' can also be a
2435 regexp to match against repository hostnames; only files from hosts
2436 that match it are treated locally. If the variable is nil, then VC
2437 queries the repository just as often as it does for local files.
2438
2439 If `vc-cvs-stay-local' is on, then VC also makes local backups of
2440 repository versions. This means that ordinary diffs (C-x v =) and
2441 revert operations (C-x v u) can be done completely locally, without
2442 any repository interactions at all. The name of a local version
2443 backup of FILE is FILE.~REV.~, where REV is the repository version
2444 number. This format is similar to that used by C-x v ~
2445 (vc-version-other-window), except for the trailing dot. As a matter
2446 of fact, the two features can each use the files created by the other,
2447 the only difference being that files with a trailing `.' are deleted
2448 automatically after commit. (This feature doesn't work on MS-DOS,
2449 since DOS disallows more than a single dot in the trunk of a file
2450 name.)
2451
2452 If `vc-cvs-stay-local' is on, and there have been changes in the
2453 repository, VC notifies you about it when you actually try to commit.
2454 If you want to check for updates from the repository without trying to
2455 commit, you can either use C-x v m RET to perform an update on the
2456 current file, or you can use C-x v r RET to get an update for an
2457 entire directory tree.
2458
2459 The new user option `vc-cvs-use-edit' indicates whether VC should call
2460 "cvs edit" to make files writeable; it defaults to `t'. (This option
2461 is only meaningful if the CVSREAD variable is set, or if files are
2462 "watched" by other developers.)
2463
2464 The commands C-x v s (vc-create-snapshot) and C-x v r
2465 (vc-retrieve-snapshot) are now also implemented for CVS. If you give
2466 an empty snapshot name to the latter, that performs a `cvs update',
2467 starting at the given directory.
2468
2469 *** Lisp Changes in VC
2470
2471 VC has been restructured internally to make it modular. You can now
2472 add support for arbitrary version control backends by writing a
2473 library that provides a certain set of backend-specific functions, and
2474 then telling VC to use that library. For example, to add support for
2475 a version system named SYS, you write a library named vc-sys.el, which
2476 provides a number of functions vc-sys-... (see commentary at the top
2477 of vc.el for a detailed list of them). To make VC use that library,
2478 you need to put it somewhere into Emacs' load path and add the symbol
2479 `SYS' to the list `vc-handled-backends'.
2480
2481 ** The customizable EDT emulation package now supports the EDT
2482 SUBS command and EDT scroll margins. It also works with more
2483 terminal/keyboard configurations and it now works under XEmacs.
2484 See etc/edt-user.doc for more information.
2485
2486 ** New modes and packages
2487
2488 *** The new global minor mode `minibuffer-electric-default-mode'
2489 automatically hides the `(default ...)' part of minibuffer prompts when
2490 the default is not applicable.
2491
2492 *** Artist is an Emacs lisp package that allows you to draw lines,
2493 rectangles and ellipses by using your mouse and/or keyboard. The
2494 shapes are made up with the ascii characters |, -, / and \.
2495
2496 Features are:
2497
2498 - Intersecting: When a `|' intersects with a `-', a `+' is
2499 drawn, like this: | \ /
2500 --+-- X
2501 | / \
2502
2503 - Rubber-banding: When drawing lines you can interactively see the
2504 result while holding the mouse button down and moving the mouse. If
2505 your machine is not fast enough (a 386 is a bit too slow, but a
2506 pentium is well enough), you can turn this feature off. You will
2507 then see 1's and 2's which mark the 1st and 2nd endpoint of the line
2508 you are drawing.
2509
2510 - Arrows: After having drawn a (straight) line or a (straight)
2511 poly-line, you can set arrows on the line-ends by typing < or >.
2512
2513 - Flood-filling: You can fill any area with a certain character by
2514 flood-filling.
2515
2516 - Cut copy and paste: You can cut, copy and paste rectangular
2517 regions. Artist also interfaces with the rect package (this can be
2518 turned off if it causes you any trouble) so anything you cut in
2519 artist can be yanked with C-x r y and vice versa.
2520
2521 - Drawing with keys: Everything you can do with the mouse, you can
2522 also do without the mouse.
2523
2524 - Aspect-ratio: You can set the variable artist-aspect-ratio to
2525 reflect the height-width ratio for the font you are using. Squares
2526 and circles are then drawn square/round. Note, that once your
2527 ascii-file is shown with font with a different height-width ratio,
2528 the squares won't be square and the circles won't be round.
2529
2530 - Drawing operations: The following drawing operations are implemented:
2531
2532 lines straight-lines
2533 rectangles squares
2534 poly-lines straight poly-lines
2535 ellipses circles
2536 text (see-thru) text (overwrite)
2537 spray-can setting size for spraying
2538 vaporize line vaporize lines
2539 erase characters erase rectangles
2540
2541 Straight lines are lines that go horizontally, vertically or
2542 diagonally. Plain lines go in any direction. The operations in
2543 the right column are accessed by holding down the shift key while
2544 drawing.
2545
2546 It is possible to vaporize (erase) entire lines and connected lines
2547 (rectangles for example) as long as the lines being vaporized are
2548 straight and connected at their endpoints. Vaporizing is inspired
2549 by the drawrect package by Jari Aalto <jari.aalto@poboxes.com>.
2550
2551 - Picture mode compatibility: Artist is picture mode compatible (this
2552 can be turned off).
2553
2554 *** The new package Eshell is an operating system command shell
2555 implemented entirely in Emacs Lisp. Use `M-x eshell' to invoke it.
2556 It functions similarly to bash and zsh, and allows running of Lisp
2557 functions and external commands using the same syntax. It supports
2558 history lists, aliases, extended globbing, smart scrolling, etc. It
2559 will work on any platform Emacs has been ported to. And since most of
2560 the basic commands -- ls, rm, mv, cp, ln, du, cat, etc. -- have been
2561 rewritten in Lisp, it offers an operating-system independent shell,
2562 all within the scope of your Emacs process.
2563
2564 *** The new package timeclock.el is a mode is for keeping track of time
2565 intervals. You can use it for whatever purpose you like, but the
2566 typical scenario is to keep track of how much time you spend working
2567 on certain projects.
2568
2569 *** The new package hi-lock.el provides commands to highlight matches
2570 of interactively entered regexps. For example,
2571
2572 M-x highlight-regexp RET clearly RET RET
2573
2574 will highlight all occurrences of `clearly' using a yellow background
2575 face. New occurrences of `clearly' will be highlighted as they are
2576 typed. `M-x unhighlight-regexp RET' will remove the highlighting.
2577 Any existing face can be used for highlighting and a set of
2578 appropriate faces is provided. The regexps can be written into the
2579 current buffer in a form that will be recognized the next time the
2580 corresponding file is read. There are commands to highlight matches
2581 to phrases and to highlight entire lines containing a match.
2582
2583 *** The new package zone.el plays games with Emacs' display when
2584 Emacs is idle.
2585
2586 *** The new package tildify.el allows to add hard spaces or other text
2587 fragments in accordance with the current major mode.
2588
2589 *** The new package xml.el provides a simple but generic XML
2590 parser. It doesn't parse the DTDs however.
2591
2592 *** The comment operations are now provided by the newcomment.el
2593 package which allows different styles of comment-region and should
2594 be more robust while offering the same functionality.
2595 `comment-region' now doesn't always comment a-line-at-a-time, but only
2596 comments the region, breaking the line at point if necessary.
2597
2598 *** The Ebrowse package implements a C++ class browser and tags
2599 facilities tailored for use with C++. It is documented in a
2600 separate Texinfo file.
2601
2602 *** The PCL-CVS package available by either running M-x cvs-examine or
2603 by visiting a CVS administrative directory (with a prefix argument)
2604 provides an alternative interface to VC-dired for CVS. It comes with
2605 `log-view-mode' to view RCS and SCCS logs and `log-edit-mode' used to
2606 enter check-in log messages.
2607
2608 *** The new package called `woman' allows to browse Unix man pages
2609 without invoking external programs.
2610
2611 The command `M-x woman' formats manual pages entirely in Emacs Lisp
2612 and then displays them, like `M-x manual-entry' does. Unlike
2613 `manual-entry', `woman' does not invoke any external programs, so it
2614 is useful on systems such as MS-DOS/MS-Windows where the `man' and
2615 Groff or `troff' commands are not readily available.
2616
2617 The command `M-x woman-find-file' asks for the file name of a man
2618 page, then formats and displays it like `M-x woman' does.
2619
2620 *** The new command M-x re-builder offers a convenient interface for
2621 authoring regular expressions with immediate visual feedback.
2622
2623 The buffer from which the command was called becomes the target for
2624 the regexp editor popping up in a separate window. Matching text in
2625 the target buffer is immediately color marked during the editing.
2626 Each sub-expression of the regexp will show up in a different face so
2627 even complex regexps can be edited and verified on target data in a
2628 single step.
2629
2630 On displays not supporting faces the matches instead blink like
2631 matching parens to make them stand out. On such a setup you will
2632 probably also want to use the sub-expression mode when the regexp
2633 contains such to get feedback about their respective limits.
2634
2635 *** glasses-mode is a minor mode that makes
2636 unreadableIdentifiersLikeThis readable. It works as glasses, without
2637 actually modifying content of a buffer.
2638
2639 *** The package ebnf2ps translates an EBNF to a syntactic chart in
2640 PostScript.
2641
2642 Currently accepts ad-hoc EBNF, ISO EBNF and Bison/Yacc.
2643
2644 The ad-hoc default EBNF syntax has the following elements:
2645
2646 ; comment (until end of line)
2647 A non-terminal
2648 "C" terminal
2649 ?C? special
2650 $A default non-terminal
2651 $"C" default terminal
2652 $?C? default special
2653 A = B. production (A is the header and B the body)
2654 C D sequence (C occurs before D)
2655 C | D alternative (C or D occurs)
2656 A - B exception (A excluding B, B without any non-terminal)
2657 n * A repetition (A repeats n (integer) times)
2658 (C) group (expression C is grouped together)
2659 [C] optional (C may or not occurs)
2660 C+ one or more occurrences of C
2661 {C}+ one or more occurrences of C
2662 {C}* zero or more occurrences of C
2663 {C} zero or more occurrences of C
2664 C / D equivalent to: C {D C}*
2665 {C || D}+ equivalent to: C {D C}*
2666 {C || D}* equivalent to: [C {D C}*]
2667 {C || D} equivalent to: [C {D C}*]
2668
2669 Please, see ebnf2ps documentation for EBNF syntax and how to use it.
2670
2671 *** The package align.el will align columns within a region, using M-x
2672 align. Its mode-specific rules, based on regular expressions,
2673 determine where the columns should be split. In C and C++, for
2674 example, it will align variable names in declaration lists, or the
2675 equal signs of assignments.
2676
2677 *** `paragraph-indent-minor-mode' is a new minor mode supporting
2678 paragraphs in the same style as `paragraph-indent-text-mode'.
2679
2680 *** bs.el is a new package for buffer selection similar to
2681 list-buffers or electric-buffer-list. Use M-x bs-show to display a
2682 buffer menu with this package. See the Custom group `bs'.
2683
2684 *** find-lisp.el is a package emulating the Unix find command in Lisp.
2685
2686 *** calculator.el is a small calculator package that is intended to
2687 replace desktop calculators such as xcalc and calc.exe. Actually, it
2688 is not too small - it has more features than most desktop calculators,
2689 and can be customized easily to get many more functions. It should
2690 not be confused with "calc" which is a much bigger mathematical tool
2691 which answers different needs.
2692
2693 *** The minor modes cwarn-mode and global-cwarn-mode highlights
2694 suspicious C and C++ constructions. Currently, assignments inside
2695 expressions, semicolon following `if', `for' and `while' (except, of
2696 course, after a `do .. while' statement), and C++ functions with
2697 reference parameters are recognized. The modes require font-lock mode
2698 to be enabled.
2699
2700 *** smerge-mode.el provides `smerge-mode', a simple minor-mode for files
2701 containing diff3-style conflict markers, such as generated by RCS.
2702
2703 *** 5x5.el is a simple puzzle game.
2704
2705 *** hl-line.el provides `hl-line-mode', a minor mode to highlight the
2706 current line in the current buffer. It also provides
2707 `global-hl-line-mode' to provide the same behaviour in all buffers.
2708
2709 *** ansi-color.el translates ANSI terminal escapes into text-properties.
2710
2711 Please note: if `ansi-color-for-comint-mode' and
2712 `global-font-lock-mode' are non-nil, loading ansi-color.el will
2713 disable font-lock and add `ansi-color-apply' to
2714 `comint-preoutput-filter-functions' for all shell-mode buffers. This
2715 displays the output of "ls --color=yes" using the correct foreground
2716 and background colors.
2717
2718 *** delphi.el provides a major mode for editing the Delphi (Object
2719 Pascal) language.
2720
2721 *** quickurl.el provides a simple method of inserting a URL based on
2722 the text at point.
2723
2724 *** sql.el provides an interface to SQL data bases.
2725
2726 *** fortune.el uses the fortune program to create mail/news signatures.
2727
2728 *** whitespace.el is a package for warning about and cleaning bogus
2729 whitespace in a file.
2730
2731 *** PostScript mode (ps-mode) is a new major mode for editing PostScript
2732 files. It offers: interaction with a PostScript interpreter, including
2733 (very basic) error handling; fontification, easily customizable for
2734 interpreter messages; auto-indentation; insertion of EPSF templates and
2735 often used code snippets; viewing of BoundingBox; commenting out /
2736 uncommenting regions; conversion of 8bit characters to PostScript octal
2737 codes. All functionality is accessible through a menu.
2738
2739 *** delim-col helps to prettify columns in a text region or rectangle.
2740
2741 Here is an example of columns:
2742
2743 horse apple bus
2744 dog pineapple car EXTRA
2745 porcupine strawberry airplane
2746
2747 Doing the following settings:
2748
2749 (setq delimit-columns-str-before "[ ")
2750 (setq delimit-columns-str-after " ]")
2751 (setq delimit-columns-str-separator ", ")
2752 (setq delimit-columns-separator "\t")
2753
2754
2755 Selecting the lines above and typing:
2756
2757 M-x delimit-columns-region
2758
2759 It results:
2760
2761 [ horse , apple , bus , ]
2762 [ dog , pineapple , car , EXTRA ]
2763 [ porcupine, strawberry, airplane, ]
2764
2765 delim-col has the following options:
2766
2767 delimit-columns-str-before Specify a string to be inserted
2768 before all columns.
2769
2770 delimit-columns-str-separator Specify a string to be inserted
2771 between each column.
2772
2773 delimit-columns-str-after Specify a string to be inserted
2774 after all columns.
2775
2776 delimit-columns-separator Specify a regexp which separates
2777 each column.
2778
2779 delim-col has the following commands:
2780
2781 delimit-columns-region Prettify all columns in a text region.
2782 delimit-columns-rectangle Prettify all columns in a text rectangle.
2783
2784 *** Recentf mode maintains a menu for visiting files that were
2785 operated on recently. User option recentf-menu-filter specifies a
2786 menu filter function to change the menu appearance. For example, the
2787 recent file list can be displayed:
2788
2789 - organized by major modes, directories or user defined rules.
2790 - sorted by file paths, file names, ascending or descending.
2791 - showing paths relative to the current default-directory
2792
2793 The `recentf-filter-changer' menu filter function allows to
2794 dynamically change the menu appearance.
2795
2796 *** elide-head.el provides a mechanism for eliding boilerplate header
2797 text.
2798
2799 *** footnote.el provides `footnote-mode', a minor mode supporting use
2800 of footnotes. It is intended for use with Message mode, but isn't
2801 specific to Message mode.
2802
2803 *** diff-mode.el provides `diff-mode', a major mode for
2804 viewing/editing context diffs (patches). It is selected for files
2805 with extension `.diff', `.diffs', `.patch' and `.rej'.
2806
2807 *** EUDC, the Emacs Unified Directory Client, provides a common user
2808 interface to access directory servers using different directory
2809 protocols. It has a separate manual.
2810
2811 *** autoconf.el provides a major mode for editing configure.in files
2812 for Autoconf, selected automatically.
2813
2814 *** windmove.el provides moving between windows.
2815
2816 *** crm.el provides a facility to read multiple strings from the
2817 minibuffer with completion.
2818
2819 *** todo-mode.el provides management of TODO lists and integration
2820 with the diary features.
2821
2822 *** autoarg.el provides a feature reported from Twenex Emacs whereby
2823 numeric keys supply prefix args rather than self inserting.
2824
2825 *** The function `turn-off-auto-fill' unconditionally turns off Auto
2826 Fill mode.
2827
2828 *** pcomplete.el is a library that provides programmable completion
2829 facilities for Emacs, similar to what zsh and tcsh offer. The main
2830 difference is that completion functions are written in Lisp, meaning
2831 they can be profiled, debugged, etc.
2832
2833 *** antlr-mode is a new major mode for editing ANTLR grammar files.
2834 It is automatically turned on for files whose names have the extension
2835 `.g'.
2836
2837 ** Changes in sort.el
2838
2839 The function sort-numeric-fields interprets numbers starting with `0'
2840 as octal and numbers starting with `0x' or `0X' as hexadecimal. The
2841 new user-option sort-numeric-base can be used to specify a default
2842 numeric base.
2843
2844 ** Changes to Ange-ftp
2845
2846 *** Ange-ftp allows you to specify of a port number in remote file
2847 names cleanly. It is appended to the host name, separated by a hash
2848 sign, e.g. `/foo@bar.org#666:mumble'. (This syntax comes from EFS.)
2849
2850 *** If the new user-option `ange-ftp-try-passive-mode' is set, passive
2851 ftp mode will be used if the ftp client supports that.
2852
2853 *** Ange-ftp handles the output of the w32-style clients which
2854 output ^M at the end of lines.
2855
2856 ** The recommended way of using Iswitchb is via the new global minor
2857 mode `iswitchb-mode'.
2858
2859 ** Just loading the msb package doesn't switch on Msb mode anymore.
2860 If you have `(require 'msb)' in your .emacs, please replace it with
2861 `(msb-mode 1)'.
2862
2863 ** Flyspell mode has various new options. See the `flyspell' Custom
2864 group.
2865
2866 ** The user option `backward-delete-char-untabify-method' controls the
2867 behavior of `backward-delete-char-untabify'. The following values
2868 are recognized:
2869
2870 `untabify' -- turn a tab to many spaces, then delete one space;
2871 `hungry' -- delete all whitespace, both tabs and spaces;
2872 `all' -- delete all whitespace, including tabs, spaces and newlines;
2873 nil -- just delete one character.
2874
2875 Default value is `untabify'.
2876
2877 [This change was made in Emacs 20.3 but not mentioned then.]
2878
2879 ** In Cperl mode `cperl-invalid-face' should now be a normal face
2880 symbol, not double-quoted.
2881
2882 ** Some packages are declared obsolete, to be removed in a future
2883 version. They are: auto-show, c-mode, hilit19, hscroll, ooutline,
2884 profile, rnews, rnewspost, and sc. Their implementations have been
2885 moved to lisp/obsolete.
2886
2887 ** auto-compression mode is no longer enabled just by loading jka-compr.el.
2888 To control it, set `auto-compression-mode' via Custom or use the
2889 `auto-compression-mode' command.
2890
2891 ** `browse-url-gnome-moz' is a new option for
2892 `browse-url-browser-function', invoking Mozilla in GNOME, and
2893 `browse-url-kde' can be chosen for invoking the KDE browser.
2894
2895 ** The user-option `browse-url-new-window-p' has been renamed to
2896 `browse-url-new-window-flag'.
2897
2898 ** The functions `keep-lines', `flush-lines' and `how-many' now
2899 operate on the active region in Transient Mark mode.
2900
2901 ** `gnus-user-agent' is a new possibility for `mail-user-agent'. It
2902 is like `message-user-agent', but with all the Gnus paraphernalia.
2903
2904 ** The Strokes package has been updated. If your Emacs has XPM
2905 support, you can use it for pictographic editing. In Strokes mode,
2906 use C-mouse-2 to compose a complex stoke and insert it into the
2907 buffer. You can encode or decode a strokes buffer with new commands
2908 M-x strokes-encode-buffer and M-x strokes-decode-buffer. There is a
2909 new command M-x strokes-list-strokes.
2910
2911 ** Hexl contains a new command `hexl-insert-hex-string' which inserts
2912 a string of hexadecimal numbers read from the mini-buffer.
2913
2914 ** Hexl mode allows to insert non-ASCII characters.
2915
2916 The non-ASCII characters are encoded using the same encoding as the
2917 file you are visiting in Hexl mode.
2918
2919 ** Shell script mode changes.
2920
2921 Shell script mode (sh-script) can now indent scripts for shells
2922 derived from sh and rc. The indentation style is customizable, and
2923 sh-script can attempt to "learn" the current buffer's style.
2924
2925 ** Etags changes.
2926
2927 *** In DOS, etags looks for file.cgz if it cannot find file.c.
2928
2929 *** New option --ignore-case-regex is an alternative to --regex. It is now
2930 possible to bind a regexp to a language, by prepending the regexp with
2931 {lang}, where lang is one of the languages that `etags --help' prints out.
2932 This feature is useful especially for regex files, where each line contains
2933 a regular expression. The manual contains details.
2934
2935 *** In C and derived languages, etags creates tags for function
2936 declarations when given the --declarations option.
2937
2938 *** In C++, tags are created for "operator". The tags have the form
2939 "operator+", without spaces between the keyword and the operator.
2940
2941 *** You shouldn't generally need any more the -C or -c++ option: etags
2942 automatically switches to C++ parsing when it meets the `class' or
2943 `template' keywords.
2944
2945 *** Etags now is able to delve at arbitrary deeps into nested structures in
2946 C-like languages. Previously, it was limited to one or two brace levels.
2947
2948 *** New language Ada: tags are functions, procedures, packages, tasks, and
2949 types.
2950
2951 *** In Fortran, `procedure' is not tagged.
2952
2953 *** In Java, tags are created for "interface".
2954
2955 *** In Lisp, "(defstruct (foo", "(defun (operator" and similar constructs
2956 are now tagged.
2957
2958 *** In makefiles, tags the targets.
2959
2960 *** In Perl, the --globals option tags global variables. my and local
2961 variables are tagged.
2962
2963 *** New language Python: def and class at the beginning of a line are tags.
2964
2965 *** .ss files are Scheme files, .pdb is Postscript with C syntax, .psw is
2966 for PSWrap.
2967
2968 ** Changes in etags.el
2969
2970 *** The new user-option tags-case-fold-search can be used to make
2971 tags operations case-sensitive or case-insensitive. The default
2972 is to use the same setting as case-fold-search.
2973
2974 *** You can display additional output with M-x tags-apropos by setting
2975 the new variable tags-apropos-additional-actions.
2976
2977 If non-nil, the variable's value should be a list of triples (TITLE
2978 FUNCTION TO-SEARCH). For each triple, M-x tags-apropos processes
2979 TO-SEARCH and lists tags from it. TO-SEARCH should be an alist,
2980 obarray, or symbol. If it is a symbol, the symbol's value is used.
2981
2982 TITLE is a string to use to label the list of tags from TO-SEARCH.
2983
2984 FUNCTION is a function to call when an entry is selected in the Tags
2985 List buffer. It is called with one argument, the selected symbol.
2986
2987 A useful example value for this variable might be something like:
2988
2989 '(("Emacs Lisp" Info-goto-emacs-command-node obarray)
2990 ("Common Lisp" common-lisp-hyperspec common-lisp-hyperspec-obarray)
2991 ("SCWM" scwm-documentation scwm-obarray))
2992
2993 *** The face tags-tag-face can be used to customize the appearance
2994 of tags in the output of M-x tags-apropos.
2995
2996 *** Setting tags-apropos-verbose to a non-nil value displays the
2997 names of tags files in the *Tags List* buffer.
2998
2999 *** You can now search for tags that are part of the filename itself.
3000 If you have tagged the files topfile.c subdir/subfile.c
3001 /tmp/tempfile.c, you can now search for tags "topfile.c", "subfile.c",
3002 "dir/sub", "tempfile", "tempfile.c". If the tag matches the file name,
3003 point will go to the beginning of the file.
3004
3005 *** Compressed files are now transparently supported if
3006 auto-compression-mode is active. You can tag (with Etags) and search
3007 (with find-tag) both compressed and uncompressed files.
3008
3009 *** Tags commands like M-x tags-search no longer change point
3010 in buffers where no match is found. In buffers where a match is
3011 found, the original value of point is pushed on the marker ring.
3012
3013 ** Fortran mode has a new command `fortran-strip-sequence-nos' to
3014 remove text past column 72. The syntax class of `\' in Fortran is now
3015 appropriate for C-style escape sequences in strings.
3016
3017 ** SGML mode's default `sgml-validate-command' is now `nsgmls'.
3018
3019 ** A new command `view-emacs-problems' (C-h P) displays the PROBLEMS file.
3020
3021 ** The Dabbrev package has a new user-option `dabbrev-ignored-regexps'
3022 containing a list of regular expressions. Buffers matching a regular
3023 expression from that list, are not checked.
3024
3025 ** Emacs can now figure out modification times of remote files.
3026 When you do C-x C-f /user@host:/path/file RET and edit the file,
3027 and someone else modifies the file, you will be prompted to revert
3028 the buffer, just like for the local files.
3029
3030 ** The buffer menu (C-x C-b) no longer lists the *Buffer List* buffer.
3031
3032 ** When invoked with a prefix argument, the command `list-abbrevs' now
3033 displays local abbrevs, only.
3034
3035 ** Refill minor mode provides preliminary support for keeping
3036 paragraphs filled as you modify them.
3037
3038 ** The variable `double-click-fuzz' specifies how much the mouse
3039 may be moved between clicks that are recognized as a pair. Its value
3040 is measured in pixels.
3041
3042 ** The new global minor mode `auto-image-file-mode' allows image files
3043 to be visited as images.
3044
3045 ** Two new user-options `grep-command' and `grep-find-command'
3046 were added to compile.el.
3047
3048 ** Withdrawn packages
3049
3050 *** mldrag.el has been removed. mouse.el provides the same
3051 functionality with aliases for the mldrag functions.
3052
3053 *** eval-reg.el has been obsoleted by changes to edebug.el and removed.
3054
3055 *** ph.el has been obsoleted by EUDC and removed.
3056
3057 \f
3058 * Incompatible Lisp changes
3059
3060 There are a few Lisp changes which are not backwards-compatible and
3061 may require changes to existing code. Here is a list for reference.
3062 See the sections below for details.
3063
3064 ** Since `format' preserves text properties, the idiom
3065 `(format "%s" foo)' no longer works to copy and remove properties.
3066 Use `copy-sequence' to copy the string, then use `set-text-properties'
3067 to remove the properties of the copy.
3068
3069 ** Since the `keymap' text property now has significance, some code
3070 which uses both `local-map' and `keymap' properties (for portability)
3071 may, for instance, give rise to duplicate menus when the keymaps from
3072 these properties are active.
3073
3074 ** The change in the treatment of non-ASCII characters in search
3075 ranges may affect some code.
3076
3077 ** A non-nil value for the LOCAL arg of add-hook makes the hook
3078 buffer-local even if `make-local-hook' hasn't been called, which might
3079 make a difference to some code.
3080
3081 ** The new treatment of the minibuffer prompt might affect code which
3082 operates on the minibuffer.
3083
3084 ** The new character sets `eight-bit-control' and `eight-bit-graphic'
3085 cause `no-conversion' and `emacs-mule-unix' coding systems to produce
3086 different results when reading files with non-ASCII characters
3087 (previously, both coding systems would produce the same results).
3088 Specifically, `no-conversion' interprets each 8-bit byte as a separate
3089 character. This makes `no-conversion' inappropriate for reading
3090 multibyte text, e.g. buffers written to disk in their internal MULE
3091 encoding (auto-saving does that, for example). If a Lisp program
3092 reads such files with `no-conversion', each byte of the multibyte
3093 sequence, including the MULE leading codes such as \201, is treated as
3094 a separate character, which prevents them from being interpreted in
3095 the buffer as multibyte characters.
3096
3097 Therefore, Lisp programs that read files which contain the internal
3098 MULE encoding should use `emacs-mule-unix'. `no-conversion' is only
3099 appropriate for reading truly binary files.
3100
3101 ** Code that relies on the obsolete `before-change-function' and
3102 `after-change-function' to detect buffer changes will now fail. Use
3103 `before-change-functions' and `after-change-functions' instead.
3104
3105 ** Code that uses `concat' with integer args now gets an error, as
3106 long promised.
3107
3108 ** The function base64-decode-string now always returns a unibyte
3109 string.
3110
3111 ** Not a Lisp incompatibility as such but, with the introduction of
3112 extra private charsets, there is now only one slot free for a new
3113 dimension-2 private charset. User code which tries to add more than
3114 one extra will fail unless you rebuild Emacs with some standard
3115 charset(s) removed; that is probably inadvisable because it changes
3116 the emacs-mule encoding. Also, files stored in the emacs-mule
3117 encoding using Emacs 20 with additional private charsets defined will
3118 probably not be read correctly by Emacs 21.
3119
3120 ** The variable `directory-sep-char' is slated for removal.
3121 Not really a change (yet), but a projected one that you should be
3122 aware of: The variable `directory-sep-char' is deprecated, and should
3123 not be used. It was always ignored on GNU/Linux and Unix systems and
3124 on MS-DOS, but the MS-Windows port tried to support it by adapting the
3125 behavior of certain primitives to the value of this variable. It
3126 turned out that such support cannot be reliable, so it was decided to
3127 remove this variable in the near future. Lisp programs are well
3128 advised not to set it to anything but '/', because any different value
3129 will not have any effect when support for this variable is removed.
3130
3131 \f
3132 * Lisp changes made after edition 2.6 of the Emacs Lisp Manual,
3133 (Display-related features are described in a page of their own below.)
3134
3135 ** Function assq-delete-all replaces function assoc-delete-all.
3136
3137 ** The new function animate-string, from lisp/play/animate.el
3138 allows the animated display of strings.
3139
3140 ** The new function `interactive-form' can be used to obtain the
3141 interactive form of a function.
3142
3143 ** The keyword :set-after in defcustom allows to specify dependencies
3144 between custom options. Example:
3145
3146 (defcustom default-input-method nil
3147 "*Default input method for multilingual text (a string).
3148 This is the input method activated automatically by the command
3149 `toggle-input-method' (\\[toggle-input-method])."
3150 :group 'mule
3151 :type '(choice (const nil) string)
3152 :set-after '(current-language-environment))
3153
3154 This specifies that default-input-method should be set after
3155 current-language-environment even if default-input-method appears
3156 first in a custom-set-variables statement.
3157
3158 ** The new hook `kbd-macro-termination-hook' is run at the end of
3159 function execute-kbd-macro. Functions on this hook are called with no
3160 args. The hook is run independent of how the macro was terminated
3161 (signal or normal termination).
3162
3163 ** Functions `butlast' and `nbutlast' for removing trailing elements
3164 from a list are now available without requiring the CL package.
3165
3166 ** The new user-option `even-window-heights' can be set to nil
3167 to prevent `display-buffer' from evening out window heights.
3168
3169 ** The user-option `face-font-registry-alternatives' specifies
3170 alternative font registry names to try when looking for a font.
3171
3172 ** Function `md5' calculates the MD5 "message digest"/"checksum".
3173
3174 ** Function `delete-frame' runs `delete-frame-hook' before actually
3175 deleting the frame. The hook is called with one arg, the frame
3176 being deleted.
3177
3178 ** `add-hook' now makes the hook local if called with a non-nil LOCAL arg.
3179
3180 ** The treatment of non-ASCII characters in search ranges has changed.
3181 If a range in a regular expression or the arg of
3182 skip-chars-forward/backward starts with a unibyte character C and ends
3183 with a multibyte character C2, the range is divided into two: one is
3184 C..?\377, the other is C1..C2, where C1 is the first character of C2's
3185 charset.
3186
3187 ** The new function `display-message-or-buffer' displays a message in
3188 the echo area or pops up a buffer, depending on the length of the
3189 message.
3190
3191 ** The new macro `with-auto-compression-mode' allows evaluating an
3192 expression with auto-compression-mode enabled.
3193
3194 ** In image specifications, `:heuristic-mask' has been replaced
3195 with the more general `:mask' property.
3196
3197 ** Image specifications accept more `:conversion's.
3198
3199 ** A `?' can be used in a symbol name without escaping it with a
3200 backslash.
3201
3202 ** Reading from the mini-buffer now reads from standard input if Emacs
3203 is running in batch mode. For example,
3204
3205 (message "%s" (read t))
3206
3207 will read a Lisp expression from standard input and print the result
3208 to standard output.
3209
3210 ** The argument of `down-list', `backward-up-list', `up-list',
3211 `kill-sexp', `backward-kill-sexp' and `mark-sexp' is now optional.
3212
3213 ** If `display-buffer-reuse-frames' is set, function `display-buffer'
3214 will raise frames displaying a buffer, instead of creating a new
3215 frame or window.
3216
3217 ** Two new functions for removing elements from lists/sequences
3218 were added
3219
3220 - Function: remove ELT SEQ
3221
3222 Return a copy of SEQ with all occurrences of ELT removed. SEQ must be
3223 a list, vector, or string. The comparison is done with `equal'.
3224
3225 - Function: remq ELT LIST
3226
3227 Return a copy of LIST with all occurrences of ELT removed. The
3228 comparison is done with `eq'.
3229
3230 ** The function `delete' now also works with vectors and strings.
3231
3232 ** The meaning of the `:weakness WEAK' argument of make-hash-table
3233 has been changed: WEAK can now have new values `key-or-value' and
3234 `key-and-value', in addition the `nil', `key', `value', and `t'.
3235
3236 ** Function `aset' stores any multibyte character in any string
3237 without signaling "Attempt to change char length of a string". It may
3238 convert a unibyte string to multibyte if necessary.
3239
3240 ** The value of the `help-echo' text property is called as a function
3241 or evaluated, if it is not a string already, to obtain a help string.
3242
3243 ** Function `make-obsolete' now has an optional arg to say when the
3244 function was declared obsolete.
3245
3246 ** Function `plist-member' is renamed from `widget-plist-member' (which is
3247 retained as an alias).
3248
3249 ** Easy-menu's :filter now works as in XEmacs.
3250 It takes the unconverted (i.e. XEmacs) form of the menu and the result
3251 is automatically converted to Emacs' form.
3252
3253 ** The new function `window-list' has been defined
3254
3255 - Function: window-list &optional FRAME WINDOW MINIBUF
3256
3257 Return a list of windows on FRAME, starting with WINDOW. FRAME nil or
3258 omitted means use the selected frame. WINDOW nil or omitted means use
3259 the selected window. MINIBUF t means include the minibuffer window,
3260 even if it isn't active. MINIBUF nil or omitted means include the
3261 minibuffer window only if it's active. MINIBUF neither nil nor t
3262 means never include the minibuffer window.
3263
3264 ** There's a new function `get-window-with-predicate' defined as follows
3265
3266 - Function: get-window-with-predicate PREDICATE &optional MINIBUF ALL-FRAMES DEFAULT
3267
3268 Return a window satisfying PREDICATE.
3269
3270 This function cycles through all visible windows using `walk-windows',
3271 calling PREDICATE on each one. PREDICATE is called with a window as
3272 argument. The first window for which PREDICATE returns a non-nil
3273 value is returned. If no window satisfies PREDICATE, DEFAULT is
3274 returned.
3275
3276 Optional second arg MINIBUF t means count the minibuffer window even
3277 if not active. MINIBUF nil or omitted means count the minibuffer iff
3278 it is active. MINIBUF neither t nor nil means not to count the
3279 minibuffer even if it is active.
3280
3281 Several frames may share a single minibuffer; if the minibuffer
3282 counts, all windows on all frames that share that minibuffer count
3283 too. Therefore, if you are using a separate minibuffer frame
3284 and the minibuffer is active and MINIBUF says it counts,
3285 `walk-windows' includes the windows in the frame from which you
3286 entered the minibuffer, as well as the minibuffer window.
3287
3288 ALL-FRAMES is the optional third argument.
3289 ALL-FRAMES nil or omitted means cycle within the frames as specified above.
3290 ALL-FRAMES = `visible' means include windows on all visible frames.
3291 ALL-FRAMES = 0 means include windows on all visible and iconified frames.
3292 ALL-FRAMES = t means include windows on all frames including invisible frames.
3293 If ALL-FRAMES is a frame, it means include windows on that frame.
3294 Anything else means restrict to the selected frame.
3295
3296 ** The function `single-key-description' now encloses function key and
3297 event names in angle brackets. When called with a second optional
3298 argument non-nil, angle brackets won't be printed.
3299
3300 ** If the variable `message-truncate-lines' is bound to t around a
3301 call to `message', the echo area will not be resized to display that
3302 message; it will be truncated instead, as it was done in 20.x.
3303 Default value is nil.
3304
3305 ** The user option `line-number-display-limit' can now be set to nil,
3306 meaning no limit.
3307
3308 ** The new user option `line-number-display-limit-width' controls
3309 the maximum width of lines in a buffer for which Emacs displays line
3310 numbers in the mode line. The default is 200.
3311
3312 ** `select-safe-coding-system' now also checks the most preferred
3313 coding-system if buffer-file-coding-system is `undecided' and
3314 DEFAULT-CODING-SYSTEM is not specified,
3315
3316 ** The function `subr-arity' provides information about the argument
3317 list of a primitive.
3318
3319 ** `where-is-internal' now also accepts a list of keymaps.
3320
3321 ** The text property `keymap' specifies a key map which overrides the
3322 buffer's local map and the map specified by the `local-map' property.
3323 This is probably what most current uses of `local-map' want, rather
3324 than replacing the local map.
3325
3326 ** The obsolete variables `before-change-function' and
3327 `after-change-function' are no longer acted upon and have been
3328 removed. Use `before-change-functions' and `after-change-functions'
3329 instead.
3330
3331 ** The function `apropos-mode' runs the hook `apropos-mode-hook'.
3332
3333 ** `concat' no longer accepts individual integer arguments,
3334 as promised long ago.
3335
3336 ** The new function `float-time' returns the current time as a float.
3337
3338 ** The new variable auto-coding-regexp-alist specifies coding systems
3339 for reading specific files, analogous to auto-coding-alist, but
3340 patterns are checked against file contents instead of file names.
3341
3342 \f
3343 * Lisp changes in Emacs 21.1 (see following page for display-related features)
3344
3345 ** The new package rx.el provides an alternative sexp notation for
3346 regular expressions.
3347
3348 - Function: rx-to-string SEXP
3349
3350 Translate SEXP into a regular expression in string notation.
3351
3352 - Macro: rx SEXP
3353
3354 Translate SEXP into a regular expression in string notation.
3355
3356 The following are valid subforms of regular expressions in sexp
3357 notation.
3358
3359 STRING
3360 matches string STRING literally.
3361
3362 CHAR
3363 matches character CHAR literally.
3364
3365 `not-newline'
3366 matches any character except a newline.
3367 .
3368 `anything'
3369 matches any character
3370
3371 `(any SET)'
3372 matches any character in SET. SET may be a character or string.
3373 Ranges of characters can be specified as `A-Z' in strings.
3374
3375 '(in SET)'
3376 like `any'.
3377
3378 `(not (any SET))'
3379 matches any character not in SET
3380
3381 `line-start'
3382 matches the empty string, but only at the beginning of a line
3383 in the text being matched
3384
3385 `line-end'
3386 is similar to `line-start' but matches only at the end of a line
3387
3388 `string-start'
3389 matches the empty string, but only at the beginning of the
3390 string being matched against.
3391
3392 `string-end'
3393 matches the empty string, but only at the end of the
3394 string being matched against.
3395
3396 `buffer-start'
3397 matches the empty string, but only at the beginning of the
3398 buffer being matched against.
3399
3400 `buffer-end'
3401 matches the empty string, but only at the end of the
3402 buffer being matched against.
3403
3404 `point'
3405 matches the empty string, but only at point.
3406
3407 `word-start'
3408 matches the empty string, but only at the beginning or end of a
3409 word.
3410
3411 `word-end'
3412 matches the empty string, but only at the end of a word.
3413
3414 `word-boundary'
3415 matches the empty string, but only at the beginning or end of a
3416 word.
3417
3418 `(not word-boundary)'
3419 matches the empty string, but not at the beginning or end of a
3420 word.
3421
3422 `digit'
3423 matches 0 through 9.
3424
3425 `control'
3426 matches ASCII control characters.
3427
3428 `hex-digit'
3429 matches 0 through 9, a through f and A through F.
3430
3431 `blank'
3432 matches space and tab only.
3433
3434 `graphic'
3435 matches graphic characters--everything except ASCII control chars,
3436 space, and DEL.
3437
3438 `printing'
3439 matches printing characters--everything except ASCII control chars
3440 and DEL.
3441
3442 `alphanumeric'
3443 matches letters and digits. (But at present, for multibyte characters,
3444 it matches anything that has word syntax.)
3445
3446 `letter'
3447 matches letters. (But at present, for multibyte characters,
3448 it matches anything that has word syntax.)
3449
3450 `ascii'
3451 matches ASCII (unibyte) characters.
3452
3453 `nonascii'
3454 matches non-ASCII (multibyte) characters.
3455
3456 `lower'
3457 matches anything lower-case.
3458
3459 `upper'
3460 matches anything upper-case.
3461
3462 `punctuation'
3463 matches punctuation. (But at present, for multibyte characters,
3464 it matches anything that has non-word syntax.)
3465
3466 `space'
3467 matches anything that has whitespace syntax.
3468
3469 `word'
3470 matches anything that has word syntax.
3471
3472 `(syntax SYNTAX)'
3473 matches a character with syntax SYNTAX. SYNTAX must be one
3474 of the following symbols.
3475
3476 `whitespace' (\\s- in string notation)
3477 `punctuation' (\\s.)
3478 `word' (\\sw)
3479 `symbol' (\\s_)
3480 `open-parenthesis' (\\s()
3481 `close-parenthesis' (\\s))
3482 `expression-prefix' (\\s')
3483 `string-quote' (\\s\")
3484 `paired-delimiter' (\\s$)
3485 `escape' (\\s\\)
3486 `character-quote' (\\s/)
3487 `comment-start' (\\s<)
3488 `comment-end' (\\s>)
3489
3490 `(not (syntax SYNTAX))'
3491 matches a character that has not syntax SYNTAX.
3492
3493 `(category CATEGORY)'
3494 matches a character with category CATEGORY. CATEGORY must be
3495 either a character to use for C, or one of the following symbols.
3496
3497 `consonant' (\\c0 in string notation)
3498 `base-vowel' (\\c1)
3499 `upper-diacritical-mark' (\\c2)
3500 `lower-diacritical-mark' (\\c3)
3501 `tone-mark' (\\c4)
3502 `symbol' (\\c5)
3503 `digit' (\\c6)
3504 `vowel-modifying-diacritical-mark' (\\c7)
3505 `vowel-sign' (\\c8)
3506 `semivowel-lower' (\\c9)
3507 `not-at-end-of-line' (\\c<)
3508 `not-at-beginning-of-line' (\\c>)
3509 `alpha-numeric-two-byte' (\\cA)
3510 `chinse-two-byte' (\\cC)
3511 `greek-two-byte' (\\cG)
3512 `japanese-hiragana-two-byte' (\\cH)
3513 `indian-tow-byte' (\\cI)
3514 `japanese-katakana-two-byte' (\\cK)
3515 `korean-hangul-two-byte' (\\cN)
3516 `cyrillic-two-byte' (\\cY)
3517 `ascii' (\\ca)
3518 `arabic' (\\cb)
3519 `chinese' (\\cc)
3520 `ethiopic' (\\ce)
3521 `greek' (\\cg)
3522 `korean' (\\ch)
3523 `indian' (\\ci)
3524 `japanese' (\\cj)
3525 `japanese-katakana' (\\ck)
3526 `latin' (\\cl)
3527 `lao' (\\co)
3528 `tibetan' (\\cq)
3529 `japanese-roman' (\\cr)
3530 `thai' (\\ct)
3531 `vietnamese' (\\cv)
3532 `hebrew' (\\cw)
3533 `cyrillic' (\\cy)
3534 `can-break' (\\c|)
3535
3536 `(not (category CATEGORY))'
3537 matches a character that has not category CATEGORY.
3538
3539 `(and SEXP1 SEXP2 ...)'
3540 matches what SEXP1 matches, followed by what SEXP2 matches, etc.
3541
3542 `(submatch SEXP1 SEXP2 ...)'
3543 like `and', but makes the match accessible with `match-end',
3544 `match-beginning', and `match-string'.
3545
3546 `(group SEXP1 SEXP2 ...)'
3547 another name for `submatch'.
3548
3549 `(or SEXP1 SEXP2 ...)'
3550 matches anything that matches SEXP1 or SEXP2, etc. If all
3551 args are strings, use `regexp-opt' to optimize the resulting
3552 regular expression.
3553
3554 `(minimal-match SEXP)'
3555 produce a non-greedy regexp for SEXP. Normally, regexps matching
3556 zero or more occurrances of something are \"greedy\" in that they
3557 match as much as they can, as long as the overall regexp can
3558 still match. A non-greedy regexp matches as little as possible.
3559
3560 `(maximal-match SEXP)'
3561 produce a greedy regexp for SEXP. This is the default.
3562
3563 `(zero-or-more SEXP)'
3564 matches zero or more occurrences of what SEXP matches.
3565
3566 `(0+ SEXP)'
3567 like `zero-or-more'.
3568
3569 `(* SEXP)'
3570 like `zero-or-more', but always produces a greedy regexp.
3571
3572 `(*? SEXP)'
3573 like `zero-or-more', but always produces a non-greedy regexp.
3574
3575 `(one-or-more SEXP)'
3576 matches one or more occurrences of A.
3577
3578 `(1+ SEXP)'
3579 like `one-or-more'.
3580
3581 `(+ SEXP)'
3582 like `one-or-more', but always produces a greedy regexp.
3583
3584 `(+? SEXP)'
3585 like `one-or-more', but always produces a non-greedy regexp.
3586
3587 `(zero-or-one SEXP)'
3588 matches zero or one occurrences of A.
3589
3590 `(optional SEXP)'
3591 like `zero-or-one'.
3592
3593 `(? SEXP)'
3594 like `zero-or-one', but always produces a greedy regexp.
3595
3596 `(?? SEXP)'
3597 like `zero-or-one', but always produces a non-greedy regexp.
3598
3599 `(repeat N SEXP)'
3600 matches N occurrences of what SEXP matches.
3601
3602 `(repeat N M SEXP)'
3603 matches N to M occurrences of what SEXP matches.
3604
3605 `(eval FORM)'
3606 evaluate FORM and insert result. If result is a string,
3607 `regexp-quote' it.
3608
3609 `(regexp REGEXP)'
3610 include REGEXP in string notation in the result.
3611
3612 *** The features `md5' and `overlay' are now provided by default.
3613
3614 *** The special form `save-restriction' now works correctly even if the
3615 buffer is widened inside the save-restriction and changes made outside
3616 the original restriction. Previously, doing this would cause the saved
3617 restriction to be restored incorrectly.
3618
3619 *** The functions `find-charset-region' and `find-charset-string' include
3620 `eight-bit-control' and/or `eight-bit-graphic' in the returned list
3621 when they find 8-bit characters. Previously, they included `ascii' in a
3622 multibyte buffer and `unknown' in a unibyte buffer.
3623
3624 *** The functions `set-buffer-multibyte', `string-as-multibyte' and
3625 `string-as-unibyte' change the byte sequence of a buffer or a string
3626 if it contains a character from the `eight-bit-control' character set.
3627
3628 *** The handling of multibyte sequences in a multibyte buffer is
3629 changed. Previously, a byte sequence matching the pattern
3630 [\200-\237][\240-\377]+ was interpreted as a single character
3631 regardless of the length of the trailing bytes [\240-\377]+. Thus, if
3632 the sequence was longer than what the leading byte indicated, the
3633 extra trailing bytes were ignored by Lisp functions. Now such extra
3634 bytes are independent 8-bit characters belonging to the charset
3635 eight-bit-graphic.
3636
3637 ** Fontsets are now implemented using char-tables.
3638
3639 A fontset can now be specified for each independent character, for
3640 a group of characters or for a character set rather than just for a
3641 character set as previously.
3642
3643 *** The arguments of the function `set-fontset-font' are changed.
3644 They are NAME, CHARACTER, FONTNAME, and optional FRAME. The function
3645 modifies fontset NAME to use FONTNAME for CHARACTER.
3646
3647 CHARACTER may be a cons (FROM . TO), where FROM and TO are non-generic
3648 characters. In that case FONTNAME is used for all characters in the
3649 range FROM and TO (inclusive). CHARACTER may be a charset. In that
3650 case FONTNAME is used for all character in the charset.
3651
3652 FONTNAME may be a cons (FAMILY . REGISTRY), where FAMILY is the family
3653 name of a font and REGISTRY is a registry name of a font.
3654
3655 *** Variable x-charset-registry has been deleted. The default charset
3656 registries of character sets are set in the default fontset
3657 "fontset-default".
3658
3659 *** The function `create-fontset-from-fontset-spec' ignores the second
3660 argument STYLE-VARIANT. It never creates style-variant fontsets.
3661
3662 ** The method of composing characters is changed. Now character
3663 composition is done by a special text property `composition' in
3664 buffers and strings.
3665
3666 *** Charset composition is deleted. Emacs never creates a `composite
3667 character' which is an independent character with a unique character
3668 code. Thus the following functions handling `composite characters'
3669 have been deleted: composite-char-component,
3670 composite-char-component-count, composite-char-composition-rule,
3671 composite-char-composition-rule and decompose-composite-char delete.
3672 The variables leading-code-composition and min-composite-char have
3673 also been deleted.
3674
3675 *** Three more glyph reference points are added. They can be used to
3676 specify a composition rule. See the documentation of the variable
3677 `reference-point-alist' for more detail.
3678
3679 *** The function `compose-region' takes new arguments COMPONENTS and
3680 MODIFICATION-FUNC. With COMPONENTS, you can specify not only a
3681 composition rule but also characters to be composed. Such characters
3682 may differ between buffer and string text.
3683
3684 *** The function `compose-string' takes new arguments START, END,
3685 COMPONENTS, and MODIFICATION-FUNC.
3686
3687 *** The function `compose-string' puts text property `composition'
3688 directly on the argument STRING instead of returning a new string.
3689 Likewise, the function `decompose-string' just removes text property
3690 `composition' from STRING.
3691
3692 *** The new function `find-composition' returns information about
3693 a composition at a specified position in a buffer or a string.
3694
3695 *** The function `decompose-composite-char' is now labeled as
3696 obsolete.
3697
3698 ** The new coding system `mac-roman' is primarily intended for use on
3699 the Macintosh but may be used generally for Macintosh-encoded text.
3700
3701 ** The new character sets `mule-unicode-0100-24ff',
3702 `mule-unicode-2500-33ff', and `mule-unicode-e000-ffff' have been
3703 introduced for Unicode characters in the range U+0100..U+24FF,
3704 U+2500..U+33FF, U+E000..U+FFFF respectively.
3705
3706 Note that the character sets are not yet unified in Emacs, so
3707 characters which belong to charsets such as Latin-2, Greek, Hebrew,
3708 etc. and the same characters in the `mule-unicode-*' charsets are
3709 different characters, as far as Emacs is concerned. For example, text
3710 which includes Unicode characters from the Latin-2 locale cannot be
3711 encoded by Emacs with ISO 8859-2 coding system.
3712
3713 ** The new coding system `mule-utf-8' has been added.
3714 It provides limited support for decoding/encoding UTF-8 text. For
3715 details, please see the documentation string of this coding system.
3716
3717 ** The new character sets `japanese-jisx0213-1' and
3718 `japanese-jisx0213-2' have been introduced for the new Japanese
3719 standard JIS X 0213 Plane 1 and Plane 2.
3720
3721 ** The new character sets `latin-iso8859-14' and `latin-iso8859-15'
3722 have been introduced.
3723
3724 ** The new character sets `eight-bit-control' and `eight-bit-graphic'
3725 have been introduced for 8-bit characters in the ranges 0x80..0x9F and
3726 0xA0..0xFF respectively. Note that the multibyte representation of
3727 eight-bit-control is never exposed; this leads to an exception in the
3728 emacs-mule coding system, which encodes everything else to the
3729 buffer/string internal representation. Note that to search for
3730 eight-bit-graphic characters in a multibyte buffer, the search string
3731 must be multibyte, otherwise such characters will be converted to
3732 their multibyte equivalent.
3733
3734 ** If the APPEND argument of `write-region' is an integer, it seeks to
3735 that offset in the file before writing.
3736
3737 ** The function `add-minor-mode' has been added for convenience and
3738 compatibility with XEmacs (and is used internally by define-minor-mode).
3739
3740 ** The function `shell-command' now sets the default directory of the
3741 `*Shell Command Output*' buffer to the default directory of the buffer
3742 from which the command was issued.
3743
3744 ** The functions `query-replace', `query-replace-regexp',
3745 `query-replace-regexp-eval' `map-query-replace-regexp',
3746 `replace-string', `replace-regexp', and `perform-replace' take two
3747 additional optional arguments START and END that specify the region to
3748 operate on.
3749
3750 ** The new function `count-screen-lines' is a more flexible alternative
3751 to `window-buffer-height'.
3752
3753 - Function: count-screen-lines &optional BEG END COUNT-FINAL-NEWLINE WINDOW
3754
3755 Return the number of screen lines in the region between BEG and END.
3756 The number of screen lines may be different from the number of actual
3757 lines, due to line breaking, display table, etc.
3758
3759 Optional arguments BEG and END default to `point-min' and `point-max'
3760 respectively.
3761
3762 If region ends with a newline, ignore it unless optional third argument
3763 COUNT-FINAL-NEWLINE is non-nil.
3764
3765 The optional fourth argument WINDOW specifies the window used for
3766 obtaining parameters such as width, horizontal scrolling, and so
3767 on. The default is to use the selected window's parameters.
3768
3769 Like `vertical-motion', `count-screen-lines' always uses the current
3770 buffer, regardless of which buffer is displayed in WINDOW. This makes
3771 possible to use `count-screen-lines' in any buffer, whether or not it
3772 is currently displayed in some window.
3773
3774 ** The new function `mapc' is like `mapcar' but doesn't collect the
3775 argument function's results.
3776
3777 ** The functions base64-decode-region and base64-decode-string now
3778 signal an error instead of returning nil if decoding fails. Also,
3779 `base64-decode-string' now always returns a unibyte string (in Emacs
3780 20, it returned a multibyte string when the result was a valid multibyte
3781 sequence).
3782
3783 ** The function sendmail-user-agent-compose now recognizes a `body'
3784 header in the list of headers passed to it.
3785
3786 ** The new function member-ignore-case works like `member', but
3787 ignores differences in case and text representation.
3788
3789 ** The buffer-local variable cursor-type can be used to specify the
3790 cursor to use in windows displaying a buffer. Values are interpreted
3791 as follows:
3792
3793 t use the cursor specified for the frame (default)
3794 nil don't display a cursor
3795 `bar' display a bar cursor with default width
3796 (bar . WIDTH) display a bar cursor with width WIDTH
3797 others display a box cursor.
3798
3799 ** The variable open-paren-in-column-0-is-defun-start controls whether
3800 an open parenthesis in column 0 is considered to be the start of a
3801 defun. If set, the default, it is considered a defun start. If not
3802 set, an open parenthesis in column 0 has no special meaning.
3803
3804 ** The new function `string-to-syntax' can be used to translate syntax
3805 specifications in string form as accepted by `modify-syntax-entry' to
3806 the cons-cell form that is used for the values of the `syntax-table'
3807 text property, and in `font-lock-syntactic-keywords'.
3808
3809 Example:
3810
3811 (string-to-syntax "()")
3812 => (4 . 41)
3813
3814 ** Emacs' reader supports CL read syntax for integers in bases
3815 other than 10.
3816
3817 *** `#BINTEGER' or `#bINTEGER' reads INTEGER in binary (radix 2).
3818 INTEGER optionally contains a sign.
3819
3820 #b1111
3821 => 15
3822 #b-1111
3823 => -15
3824
3825 *** `#OINTEGER' or `#oINTEGER' reads INTEGER in octal (radix 8).
3826
3827 #o666
3828 => 438
3829
3830 *** `#XINTEGER' or `#xINTEGER' reads INTEGER in hexadecimal (radix 16).
3831
3832 #xbeef
3833 => 48815
3834
3835 *** `#RADIXrINTEGER' reads INTEGER in radix RADIX, 2 <= RADIX <= 36.
3836
3837 #2R-111
3838 => -7
3839 #25rah
3840 => 267
3841
3842 ** The function `documentation-property' now evaluates the value of
3843 the given property to obtain a string if it doesn't refer to etc/DOC
3844 and isn't a string.
3845
3846 ** If called for a symbol, the function `documentation' now looks for
3847 a `function-documentation' property of that symbol. If it has a non-nil
3848 value, the documentation is taken from that value. If the value is
3849 not a string, it is evaluated to obtain a string.
3850
3851 ** The last argument of `define-key-after' defaults to t for convenience.
3852
3853 ** The new function `replace-regexp-in-string' replaces all matches
3854 for a regexp in a string.
3855
3856 ** `mouse-position' now runs the abnormal hook
3857 `mouse-position-function'.
3858
3859 ** The function string-to-number now returns a float for numbers
3860 that don't fit into a Lisp integer.
3861
3862 ** The variable keyword-symbols-constants-flag has been removed.
3863 Keywords are now always considered constants.
3864
3865 ** The new function `delete-and-extract-region' deletes text and
3866 returns it.
3867
3868 ** The function `clear-this-command-keys' now also clears the vector
3869 returned by function `recent-keys'.
3870
3871 ** Variables `beginning-of-defun-function' and `end-of-defun-function'
3872 can be used to define handlers for the functions that find defuns.
3873 Major modes can define these locally instead of rebinding C-M-a
3874 etc. if the normal conventions for defuns are not appropriate for the
3875 mode.
3876
3877 ** easy-mmode-define-minor-mode now takes an additional BODY argument
3878 and is renamed `define-minor-mode'.
3879
3880 ** If an abbrev has a hook function which is a symbol, and that symbol
3881 has a non-nil `no-self-insert' property, the return value of the hook
3882 function specifies whether an expansion has been done or not. If it
3883 returns nil, abbrev-expand also returns nil, meaning "no expansion has
3884 been performed."
3885
3886 When abbrev expansion is done by typing a self-inserting character,
3887 and the abbrev has a hook with the `no-self-insert' property, and the
3888 hook function returns non-nil meaning expansion has been done,
3889 then the self-inserting character is not inserted.
3890
3891 ** The function `intern-soft' now accepts a symbol as first argument.
3892 In this case, that exact symbol is looked up in the specified obarray,
3893 and the function's value is nil if it is not found.
3894
3895 ** The new macro `with-syntax-table' can be used to evaluate forms
3896 with the syntax table of the current buffer temporarily set to a
3897 specified table.
3898
3899 (with-syntax-table TABLE &rest BODY)
3900
3901 Evaluate BODY with syntax table of current buffer set to a copy of
3902 TABLE. The current syntax table is saved, BODY is evaluated, and the
3903 saved table is restored, even in case of an abnormal exit. Value is
3904 what BODY returns.
3905
3906 ** Regular expressions now support intervals \{n,m\} as well as
3907 Perl's shy-groups \(?:...\) and non-greedy *? +? and ?? operators.
3908 Also back-references like \2 are now considered as an error if the
3909 corresponding subgroup does not exist (or is not closed yet).
3910 Previously it would have been silently turned into `2' (ignoring the `\').
3911
3912 ** The optional argument BUFFER of function file-local-copy has been
3913 removed since it wasn't used by anything.
3914
3915 ** The file name argument of function `file-locked-p' is now required
3916 instead of being optional.
3917
3918 ** The new built-in error `text-read-only' is signaled when trying to
3919 modify read-only text.
3920
3921 ** New functions and variables for locales.
3922
3923 The new variable `locale-coding-system' specifies how to encode and
3924 decode strings passed to low-level message functions like strerror and
3925 time functions like strftime. The new variables
3926 `system-messages-locale' and `system-time-locale' give the system
3927 locales to be used when invoking these two types of functions.
3928
3929 The new function `set-locale-environment' sets the language
3930 environment, preferred coding system, and locale coding system from
3931 the system locale as specified by the LC_ALL, LC_CTYPE, and LANG
3932 environment variables. Normally, it is invoked during startup and need
3933 not be invoked thereafter. It uses the new variables
3934 `locale-language-names', `locale-charset-language-names', and
3935 `locale-preferred-coding-systems' to make its decisions.
3936
3937 ** syntax tables now understand nested comments.
3938 To declare a comment syntax as allowing nesting, just add an `n'
3939 modifier to either of the characters of the comment end and the comment
3940 start sequences.
3941
3942 ** The function `pixmap-spec-p' has been renamed `bitmap-spec-p'
3943 because `bitmap' is more in line with the usual X terminology.
3944
3945 ** New function `propertize'
3946
3947 The new function `propertize' can be used to conveniently construct
3948 strings with text properties.
3949
3950 - Function: propertize STRING &rest PROPERTIES
3951
3952 Value is a copy of STRING with text properties assigned as specified
3953 by PROPERTIES. PROPERTIES is a sequence of pairs PROPERTY VALUE, with
3954 PROPERTY being the name of a text property and VALUE being the
3955 specified value of that property. Example:
3956
3957 (propertize "foo" 'face 'bold 'read-only t)
3958
3959 ** push and pop macros.
3960
3961 Simple versions of the push and pop macros of Common Lisp
3962 are now defined in Emacs Lisp. These macros allow only symbols
3963 as the place that holds the list to be changed.
3964
3965 (push NEWELT LISTNAME) add NEWELT to the front of LISTNAME's value.
3966 (pop LISTNAME) return first elt of LISTNAME, and remove it
3967 (thus altering the value of LISTNAME).
3968
3969 ** New dolist and dotimes macros.
3970
3971 Simple versions of the dolist and dotimes macros of Common Lisp
3972 are now defined in Emacs Lisp.
3973
3974 (dolist (VAR LIST [RESULT]) BODY...)
3975 Execute body once for each element of LIST,
3976 using the variable VAR to hold the current element.
3977 Then return the value of RESULT, or nil if RESULT is omitted.
3978
3979 (dotimes (VAR COUNT [RESULT]) BODY...)
3980 Execute BODY with VAR bound to successive integers running from 0,
3981 inclusive, to COUNT, exclusive.
3982 Then return the value of RESULT, or nil if RESULT is omitted.
3983
3984 ** Regular expressions now support Posix character classes such as
3985 [:alpha:], [:space:] and so on. These must be used within a character
3986 class--for instance, [-[:digit:].+] matches digits or a period
3987 or a sign.
3988
3989 [:digit:] matches 0 through 9
3990 [:cntrl:] matches ASCII control characters
3991 [:xdigit:] matches 0 through 9, a through f and A through F.
3992 [:blank:] matches space and tab only
3993 [:graph:] matches graphic characters--everything except ASCII control chars,
3994 space, and DEL.
3995 [:print:] matches printing characters--everything except ASCII control chars
3996 and DEL.
3997 [:alnum:] matches letters and digits.
3998 (But at present, for multibyte characters,
3999 it matches anything that has word syntax.)
4000 [:alpha:] matches letters.
4001 (But at present, for multibyte characters,
4002 it matches anything that has word syntax.)
4003 [:ascii:] matches ASCII (unibyte) characters.
4004 [:nonascii:] matches non-ASCII (multibyte) characters.
4005 [:lower:] matches anything lower-case.
4006 [:punct:] matches punctuation.
4007 (But at present, for multibyte characters,
4008 it matches anything that has non-word syntax.)
4009 [:space:] matches anything that has whitespace syntax.
4010 [:upper:] matches anything upper-case.
4011 [:word:] matches anything that has word syntax.
4012
4013 ** Emacs now has built-in hash tables.
4014
4015 The following functions are defined for hash tables:
4016
4017 - Function: make-hash-table ARGS
4018
4019 The argument list ARGS consists of keyword/argument pairs. All arguments
4020 are optional. The following arguments are defined:
4021
4022 :test TEST
4023
4024 TEST must be a symbol specifying how to compare keys. Default is `eql'.
4025 Predefined are `eq', `eql' and `equal'. If TEST is not predefined,
4026 it must have been defined with `define-hash-table-test'.
4027
4028 :size SIZE
4029
4030 SIZE must be an integer > 0 giving a hint to the implementation how
4031 many elements will be put in the hash table. Default size is 65.
4032
4033 :rehash-size REHASH-SIZE
4034
4035 REHASH-SIZE specifies by how much to grow a hash table once it becomes
4036 full. If REHASH-SIZE is an integer, add that to the hash table's old
4037 size to get the new size. Otherwise, REHASH-SIZE must be a float >
4038 1.0, and the new size is computed by multiplying REHASH-SIZE with the
4039 old size. Default rehash size is 1.5.
4040
4041 :rehash-threshold THRESHOLD
4042
4043 THRESHOLD must be a float > 0 and <= 1.0 specifying when to resize the
4044 hash table. It is resized when the ratio of (number of entries) /
4045 (size of hash table) is >= THRESHOLD. Default threshold is 0.8.
4046
4047 :weakness WEAK
4048
4049 WEAK must be either nil, one of the symbols `key, `value',
4050 `key-or-value', `key-and-value', or t, meaning the same as
4051 `key-and-value'. Entries are removed from weak tables during garbage
4052 collection if their key and/or value are not referenced elsewhere
4053 outside of the hash table. Default are non-weak hash tables.
4054
4055 - Function: makehash &optional TEST
4056
4057 Similar to make-hash-table, but only TEST can be specified.
4058
4059 - Function: hash-table-p TABLE
4060
4061 Returns non-nil if TABLE is a hash table object.
4062
4063 - Function: copy-hash-table TABLE
4064
4065 Returns a copy of TABLE. Only the table itself is copied, keys and
4066 values are shared.
4067
4068 - Function: hash-table-count TABLE
4069
4070 Returns the number of entries in TABLE.
4071
4072 - Function: hash-table-rehash-size TABLE
4073
4074 Returns the rehash size of TABLE.
4075
4076 - Function: hash-table-rehash-threshold TABLE
4077
4078 Returns the rehash threshold of TABLE.
4079
4080 - Function: hash-table-rehash-size TABLE
4081
4082 Returns the size of TABLE.
4083
4084 - Function: hash-table-test TABLE
4085
4086 Returns the test TABLE uses to compare keys.
4087
4088 - Function: hash-table-weakness TABLE
4089
4090 Returns the weakness specified for TABLE.
4091
4092 - Function: clrhash TABLE
4093
4094 Clear TABLE.
4095
4096 - Function: gethash KEY TABLE &optional DEFAULT
4097
4098 Look up KEY in TABLE and return its associated VALUE or DEFAULT if
4099 not found.
4100
4101 - Function: puthash KEY VALUE TABLE
4102
4103 Associate KEY with VALUE in TABLE. If KEY is already associated with
4104 another value, replace the old value with VALUE.
4105
4106 - Function: remhash KEY TABLE
4107
4108 Remove KEY from TABLE if it is there.
4109
4110 - Function: maphash FUNCTION TABLE
4111
4112 Call FUNCTION for all elements in TABLE. FUNCTION must take two
4113 arguments KEY and VALUE.
4114
4115 - Function: sxhash OBJ
4116
4117 Return a hash code for Lisp object OBJ.
4118
4119 - Function: define-hash-table-test NAME TEST-FN HASH-FN
4120
4121 Define a new hash table test named NAME. If NAME is specified as
4122 a test in `make-hash-table', the table created will use TEST-FN for
4123 comparing keys, and HASH-FN to compute hash codes for keys. Test
4124 and hash function are stored as symbol property `hash-table-test'
4125 of NAME with a value of (TEST-FN HASH-FN).
4126
4127 TEST-FN must take two arguments and return non-nil if they are the same.
4128
4129 HASH-FN must take one argument and return an integer that is the hash
4130 code of the argument. The function should use the whole range of
4131 integer values for hash code computation, including negative integers.
4132
4133 Example: The following creates a hash table whose keys are supposed to
4134 be strings that are compared case-insensitively.
4135
4136 (defun case-fold-string= (a b)
4137 (compare-strings a nil nil b nil nil t))
4138
4139 (defun case-fold-string-hash (a)
4140 (sxhash (upcase a)))
4141
4142 (define-hash-table-test 'case-fold 'case-fold-string=
4143 'case-fold-string-hash))
4144
4145 (make-hash-table :test 'case-fold)
4146
4147 ** The Lisp reader handles circular structure.
4148
4149 It now works to use the #N= and #N# constructs to represent
4150 circular structures. For example, #1=(a . #1#) represents
4151 a cons cell which is its own cdr.
4152
4153 ** The Lisp printer handles circular structure.
4154
4155 If you bind print-circle to a non-nil value, the Lisp printer outputs
4156 #N= and #N# constructs to represent circular and shared structure.
4157
4158 ** If the second argument to `move-to-column' is anything but nil or
4159 t, that means replace a tab with spaces if necessary to reach the
4160 specified column, but do not add spaces at the end of the line if it
4161 is too short to reach that column.
4162
4163 ** perform-replace has a new feature: the REPLACEMENTS argument may
4164 now be a cons cell (FUNCTION . DATA). This means to call FUNCTION
4165 after each match to get the replacement text. FUNCTION is called with
4166 two arguments: DATA, and the number of replacements already made.
4167
4168 If the FROM-STRING contains any upper-case letters,
4169 perform-replace also turns off `case-fold-search' temporarily
4170 and inserts the replacement text without altering case in it.
4171
4172 ** The function buffer-size now accepts an optional argument
4173 to specify which buffer to return the size of.
4174
4175 ** The calendar motion commands now run the normal hook
4176 calendar-move-hook after moving point.
4177
4178 ** The new variable small-temporary-file-directory specifies a
4179 directory to use for creating temporary files that are likely to be
4180 small. (Certain Emacs features use this directory.) If
4181 small-temporary-file-directory is nil, they use
4182 temporary-file-directory instead.
4183
4184 ** The variable `inhibit-modification-hooks', if non-nil, inhibits all
4185 the hooks that track changes in the buffer. This affects
4186 `before-change-functions' and `after-change-functions', as well as
4187 hooks attached to text properties and overlay properties.
4188
4189 ** assq-delete-all is a new function that deletes all the
4190 elements of an alist which have a car `eq' to a particular value.
4191
4192 ** make-temp-file provides a more reliable way to create a temporary file.
4193
4194 make-temp-file is used like make-temp-name, except that it actually
4195 creates the file before it returns. This prevents a timing error,
4196 ensuring that no other job can use the same name for a temporary file.
4197
4198 ** New exclusive-open feature in `write-region'
4199
4200 The optional seventh arg is now called MUSTBENEW. If non-nil, it insists
4201 on a check for an existing file with the same name. If MUSTBENEW
4202 is `excl', that means to get an error if the file already exists;
4203 never overwrite. If MUSTBENEW is neither nil nor `excl', that means
4204 ask for confirmation before overwriting, but do go ahead and
4205 overwrite the file if the user gives confirmation.
4206
4207 If the MUSTBENEW argument in `write-region' is `excl',
4208 that means to use a special feature in the `open' system call
4209 to get an error if the file exists at that time.
4210 The error reported is `file-already-exists'.
4211
4212 ** Function `format' now handles text properties.
4213
4214 Text properties of the format string are applied to the result string.
4215 If the result string is longer than the format string, text properties
4216 ending at the end of the format string are extended to the end of the
4217 result string.
4218
4219 Text properties from string arguments are applied to the result
4220 string where arguments appear in the result string.
4221
4222 Example:
4223
4224 (let ((s1 "hello, %s")
4225 (s2 "world"))
4226 (put-text-property 0 (length s1) 'face 'bold s1)
4227 (put-text-property 0 (length s2) 'face 'italic s2)
4228 (format s1 s2))
4229
4230 results in a bold-face string with an italic `world' at the end.
4231
4232 ** Messages can now be displayed with text properties.
4233
4234 Text properties are handled as described above for function `format'.
4235 The following example displays a bold-face message with an italic
4236 argument in it.
4237
4238 (let ((msg "hello, %s!")
4239 (arg "world"))
4240 (put-text-property 0 (length msg) 'face 'bold msg)
4241 (put-text-property 0 (length arg) 'face 'italic arg)
4242 (message msg arg))
4243
4244 ** Sound support
4245
4246 Emacs supports playing sound files on GNU/Linux and the free BSDs
4247 (Voxware driver and native BSD driver, aka as Luigi's driver).
4248
4249 Currently supported file formats are RIFF-WAVE (*.wav) and Sun Audio
4250 (*.au). You must configure Emacs with the option `--with-sound=yes'
4251 to enable sound support.
4252
4253 Sound files can be played by calling (play-sound SOUND). SOUND is a
4254 list of the form `(sound PROPERTY...)'. The function is only defined
4255 when sound support is present for the system on which Emacs runs. The
4256 functions runs `play-sound-functions' with one argument which is the
4257 sound to play, before playing the sound.
4258
4259 The following sound properties are supported:
4260
4261 - `:file FILE'
4262
4263 FILE is a file name. If FILE isn't an absolute name, it will be
4264 searched relative to `data-directory'.
4265
4266 - `:data DATA'
4267
4268 DATA is a string containing sound data. Either :file or :data
4269 may be present, but not both.
4270
4271 - `:volume VOLUME'
4272
4273 VOLUME must be an integer in the range 0..100 or a float in the range
4274 0..1. This property is optional.
4275
4276 - `:device DEVICE'
4277
4278 DEVICE is a string specifying the system device on which to play the
4279 sound. The default device is system-dependent.
4280
4281 Other properties are ignored.
4282
4283 An alternative interface is called as
4284 (play-sound-file FILE &optional VOLUME DEVICE).
4285
4286 ** `multimedia' is a new Finder keyword and Custom group.
4287
4288 ** keywordp is a new predicate to test efficiently for an object being
4289 a keyword symbol.
4290
4291 ** Changes to garbage collection
4292
4293 *** The function garbage-collect now additionally returns the number
4294 of live and free strings.
4295
4296 *** There is a new variable `strings-consed' holding the number of
4297 strings that have been consed so far.
4298
4299 \f
4300 * Lisp-level Display features added after release 2.6 of the Emacs
4301 Lisp Manual
4302
4303 ** The user-option `resize-mini-windows' controls how Emacs resizes
4304 mini-windows.
4305
4306 ** The function `pos-visible-in-window-p' now has a third optional
4307 argument, PARTIALLY. If a character is only partially visible, nil is
4308 returned, unless PARTIALLY is non-nil.
4309
4310 ** On window systems, `glyph-table' is no longer used.
4311
4312 ** Help strings in menu items are now used to provide `help-echo' text.
4313
4314 ** The function `image-size' can be used to determine the size of an
4315 image.
4316
4317 - Function: image-size SPEC &optional PIXELS FRAME
4318
4319 Return the size of an image as a pair (WIDTH . HEIGHT).
4320
4321 SPEC is an image specification. PIXELS non-nil means return sizes
4322 measured in pixels, otherwise return sizes measured in canonical
4323 character units (fractions of the width/height of the frame's default
4324 font). FRAME is the frame on which the image will be displayed.
4325 FRAME nil or omitted means use the selected frame.
4326
4327 ** The function `image-mask-p' can be used to determine if an image
4328 has a mask bitmap.
4329
4330 - Function: image-mask-p SPEC &optional FRAME
4331
4332 Return t if image SPEC has a mask bitmap.
4333 FRAME is the frame on which the image will be displayed. FRAME nil
4334 or omitted means use the selected frame.
4335
4336 ** The function `find-image' can be used to find a usable image
4337 satisfying one of a list of specifications.
4338
4339 ** The STRING argument of `put-image' and `insert-image' is now
4340 optional.
4341
4342 ** Image specifications may contain the property `:ascent center' (see
4343 below).
4344
4345 \f
4346 * New Lisp-level Display features in Emacs 21.1
4347
4348 ** The function tty-suppress-bold-inverse-default-colors can be used
4349 to make Emacs avoid displaying text with bold black foreground on TTYs.
4350
4351 Some terminals, notably PC consoles, emulate bold text by displaying
4352 text in brighter colors. On such a console, a bold black foreground
4353 is displayed in a gray color. If this turns out to be hard to read on
4354 your monitor---the problem occurred with the mode line on
4355 laptops---you can instruct Emacs to ignore the text's boldness, and to
4356 just display it black instead.
4357
4358 This situation can't be detected automatically. You will have to put
4359 a line like
4360
4361 (tty-suppress-bold-inverse-default-colors t)
4362
4363 in your `.emacs'.
4364
4365 ** New face implementation.
4366
4367 Emacs faces have been reimplemented from scratch. They don't use XLFD
4368 font names anymore and face merging now works as expected.
4369
4370 *** New faces.
4371
4372 Each face can specify the following display attributes:
4373
4374 1. Font family or fontset alias name.
4375
4376 2. Relative proportionate width, aka character set width or set
4377 width (swidth), e.g. `semi-compressed'.
4378
4379 3. Font height in 1/10pt
4380
4381 4. Font weight, e.g. `bold'.
4382
4383 5. Font slant, e.g. `italic'.
4384
4385 6. Foreground color.
4386
4387 7. Background color.
4388
4389 8. Whether or not characters should be underlined, and in what color.
4390
4391 9. Whether or not characters should be displayed in inverse video.
4392
4393 10. A background stipple, a bitmap.
4394
4395 11. Whether or not characters should be overlined, and in what color.
4396
4397 12. Whether or not characters should be strike-through, and in what
4398 color.
4399
4400 13. Whether or not a box should be drawn around characters, its
4401 color, the width of the box lines, and 3D appearance.
4402
4403 Faces are frame-local by nature because Emacs allows to define the
4404 same named face (face names are symbols) differently for different
4405 frames. Each frame has an alist of face definitions for all named
4406 faces. The value of a named face in such an alist is a Lisp vector
4407 with the symbol `face' in slot 0, and a slot for each of the face
4408 attributes mentioned above.
4409
4410 There is also a global face alist `face-new-frame-defaults'. Face
4411 definitions from this list are used to initialize faces of newly
4412 created frames.
4413
4414 A face doesn't have to specify all attributes. Those not specified
4415 have a nil value. Faces specifying all attributes are called
4416 `fully-specified'.
4417
4418 *** Face merging.
4419
4420 The display style of a given character in the text is determined by
4421 combining several faces. This process is called `face merging'. Any
4422 aspect of the display style that isn't specified by overlays or text
4423 properties is taken from the `default' face. Since it is made sure
4424 that the default face is always fully-specified, face merging always
4425 results in a fully-specified face.
4426
4427 *** Face realization.
4428
4429 After all face attributes for a character have been determined by
4430 merging faces of that character, that face is `realized'. The
4431 realization process maps face attributes to what is physically
4432 available on the system where Emacs runs. The result is a `realized
4433 face' in form of an internal structure which is stored in the face
4434 cache of the frame on which it was realized.
4435
4436 Face realization is done in the context of the charset of the
4437 character to display because different fonts and encodings are used
4438 for different charsets. In other words, for characters of different
4439 charsets, different realized faces are needed to display them.
4440
4441 Except for composite characters, faces are always realized for a
4442 specific character set and contain a specific font, even if the face
4443 being realized specifies a fontset. The reason is that the result of
4444 the new font selection stage is better than what can be done with
4445 statically defined font name patterns in fontsets.
4446
4447 In unibyte text, Emacs' charsets aren't applicable; function
4448 `char-charset' reports ASCII for all characters, including those >
4449 0x7f. The X registry and encoding of fonts to use is determined from
4450 the variable `face-default-registry' in this case. The variable is
4451 initialized at Emacs startup time from the font the user specified for
4452 Emacs.
4453
4454 Currently all unibyte text, i.e. all buffers with
4455 `enable-multibyte-characters' nil are displayed with fonts of the same
4456 registry and encoding `face-default-registry'. This is consistent
4457 with the fact that languages can also be set globally, only.
4458
4459 **** Clearing face caches.
4460
4461 The Lisp function `clear-face-cache' can be called to clear face caches
4462 on all frames. If called with a non-nil argument, it will also unload
4463 unused fonts.
4464
4465 *** Font selection.
4466
4467 Font selection tries to find the best available matching font for a
4468 given (charset, face) combination. This is done slightly differently
4469 for faces specifying a fontset, or a font family name.
4470
4471 If the face specifies a fontset name, that fontset determines a
4472 pattern for fonts of the given charset. If the face specifies a font
4473 family, a font pattern is constructed. Charset symbols have a
4474 property `x-charset-registry' for that purpose that maps a charset to
4475 an XLFD registry and encoding in the font pattern constructed.
4476
4477 Available fonts on the system on which Emacs runs are then matched
4478 against the font pattern. The result of font selection is the best
4479 match for the given face attributes in this font list.
4480
4481 Font selection can be influenced by the user.
4482
4483 The user can specify the relative importance he gives the face
4484 attributes width, height, weight, and slant by setting
4485 face-font-selection-order (faces.el) to a list of face attribute
4486 names. The default is (:width :height :weight :slant), and means
4487 that font selection first tries to find a good match for the font
4488 width specified by a face, then---within fonts with that width---tries
4489 to find a best match for the specified font height, etc.
4490
4491 Setting `face-font-family-alternatives' allows the user to specify
4492 alternative font families to try if a family specified by a face
4493 doesn't exist.
4494
4495 Setting `face-font-registry-alternatives' allows the user to specify
4496 all alternative font registry names to try for a face specifying a
4497 registry.
4498
4499 Please note that the interpretations of the above two variables are
4500 slightly different.
4501
4502 Setting face-ignored-fonts allows the user to ignore specific fonts.
4503
4504
4505 **** Scalable fonts
4506
4507 Emacs can make use of scalable fonts but doesn't do so by default,
4508 since the use of too many or too big scalable fonts may crash XFree86
4509 servers.
4510
4511 To enable scalable font use, set the variable
4512 `scalable-fonts-allowed'. A value of nil, the default, means never use
4513 scalable fonts. A value of t means any scalable font may be used.
4514 Otherwise, the value must be a list of regular expressions. A
4515 scalable font may then be used if it matches a regular expression from
4516 that list. Example:
4517
4518 (setq scalable-fonts-allowed '("muleindian-2$"))
4519
4520 allows the use of scalable fonts with registry `muleindian-2'.
4521
4522 *** Functions and variables related to font selection.
4523
4524 - Function: x-family-fonts &optional FAMILY FRAME
4525
4526 Return a list of available fonts of family FAMILY on FRAME. If FAMILY
4527 is omitted or nil, list all families. Otherwise, FAMILY must be a
4528 string, possibly containing wildcards `?' and `*'.
4529
4530 If FRAME is omitted or nil, use the selected frame. Each element of
4531 the result is a vector [FAMILY WIDTH POINT-SIZE WEIGHT SLANT FIXED-P
4532 FULL REGISTRY-AND-ENCODING]. FAMILY is the font family name.
4533 POINT-SIZE is the size of the font in 1/10 pt. WIDTH, WEIGHT, and
4534 SLANT are symbols describing the width, weight and slant of the font.
4535 These symbols are the same as for face attributes. FIXED-P is non-nil
4536 if the font is fixed-pitch. FULL is the full name of the font, and
4537 REGISTRY-AND-ENCODING is a string giving the registry and encoding of
4538 the font. The result list is sorted according to the current setting
4539 of the face font sort order.
4540
4541 - Function: x-font-family-list
4542
4543 Return a list of available font families on FRAME. If FRAME is
4544 omitted or nil, use the selected frame. Value is a list of conses
4545 (FAMILY . FIXED-P) where FAMILY is a font family, and FIXED-P is
4546 non-nil if fonts of that family are fixed-pitch.
4547
4548 - Variable: font-list-limit
4549
4550 Limit for font matching. If an integer > 0, font matching functions
4551 won't load more than that number of fonts when searching for a
4552 matching font. The default is currently 100.
4553
4554 *** Setting face attributes.
4555
4556 For the most part, the new face implementation is interface-compatible
4557 with the old one. Old face attribute related functions are now
4558 implemented in terms of the new functions `set-face-attribute' and
4559 `face-attribute'.
4560
4561 Face attributes are identified by their names which are keyword
4562 symbols. All attributes can be set to `unspecified'.
4563
4564 The following attributes are recognized:
4565
4566 `:family'
4567
4568 VALUE must be a string specifying the font family, e.g. ``courier'',
4569 or a fontset alias name. If a font family is specified, wild-cards `*'
4570 and `?' are allowed.
4571
4572 `:width'
4573
4574 VALUE specifies the relative proportionate width of the font to use.
4575 It must be one of the symbols `ultra-condensed', `extra-condensed',
4576 `condensed', `semi-condensed', `normal', `semi-expanded', `expanded',
4577 `extra-expanded', or `ultra-expanded'.
4578
4579 `:height'
4580
4581 VALUE must be either an integer specifying the height of the font to use
4582 in 1/10 pt, a floating point number specifying the amount by which to
4583 scale any underlying face, or a function, which is called with the old
4584 height (from the underlying face), and should return the new height.
4585
4586 `:weight'
4587
4588 VALUE specifies the weight of the font to use. It must be one of the
4589 symbols `ultra-bold', `extra-bold', `bold', `semi-bold', `normal',
4590 `semi-light', `light', `extra-light', `ultra-light'.
4591
4592 `:slant'
4593
4594 VALUE specifies the slant of the font to use. It must be one of the
4595 symbols `italic', `oblique', `normal', `reverse-italic', or
4596 `reverse-oblique'.
4597
4598 `:foreground', `:background'
4599
4600 VALUE must be a color name, a string.
4601
4602 `:underline'
4603
4604 VALUE specifies whether characters in FACE should be underlined. If
4605 VALUE is t, underline with foreground color of the face. If VALUE is
4606 a string, underline with that color. If VALUE is nil, explicitly
4607 don't underline.
4608
4609 `:overline'
4610
4611 VALUE specifies whether characters in FACE should be overlined. If
4612 VALUE is t, overline with foreground color of the face. If VALUE is a
4613 string, overline with that color. If VALUE is nil, explicitly don't
4614 overline.
4615
4616 `:strike-through'
4617
4618 VALUE specifies whether characters in FACE should be drawn with a line
4619 striking through them. If VALUE is t, use the foreground color of the
4620 face. If VALUE is a string, strike-through with that color. If VALUE
4621 is nil, explicitly don't strike through.
4622
4623 `:box'
4624
4625 VALUE specifies whether characters in FACE should have a box drawn
4626 around them. If VALUE is nil, explicitly don't draw boxes. If
4627 VALUE is t, draw a box with lines of width 1 in the foreground color
4628 of the face. If VALUE is a string, the string must be a color name,
4629 and the box is drawn in that color with a line width of 1. Otherwise,
4630 VALUE must be a property list of the form `(:line-width WIDTH
4631 :color COLOR :style STYLE)'. If a keyword/value pair is missing from
4632 the property list, a default value will be used for the value, as
4633 specified below. WIDTH specifies the width of the lines to draw; it
4634 defaults to 1. COLOR is the name of the color to draw in, default is
4635 the foreground color of the face for simple boxes, and the background
4636 color of the face for 3D boxes. STYLE specifies whether a 3D box
4637 should be draw. If STYLE is `released-button', draw a box looking
4638 like a released 3D button. If STYLE is `pressed-button' draw a box
4639 that appears like a pressed button. If STYLE is nil, the default if
4640 the property list doesn't contain a style specification, draw a 2D
4641 box.
4642
4643 `:inverse-video'
4644
4645 VALUE specifies whether characters in FACE should be displayed in
4646 inverse video. VALUE must be one of t or nil.
4647
4648 `:stipple'
4649
4650 If VALUE is a string, it must be the name of a file of pixmap data.
4651 The directories listed in the `x-bitmap-file-path' variable are
4652 searched. Alternatively, VALUE may be a list of the form (WIDTH
4653 HEIGHT DATA) where WIDTH and HEIGHT are the size in pixels, and DATA
4654 is a string containing the raw bits of the bitmap. VALUE nil means
4655 explicitly don't use a stipple pattern.
4656
4657 For convenience, attributes `:family', `:width', `:height', `:weight',
4658 and `:slant' may also be set in one step from an X font name:
4659
4660 `:font'
4661
4662 Set font-related face attributes from VALUE. VALUE must be a valid
4663 XLFD font name. If it is a font name pattern, the first matching font
4664 is used--this is for compatibility with the behavior of previous
4665 versions of Emacs.
4666
4667 For compatibility with Emacs 20, keywords `:bold' and `:italic' can
4668 be used to specify that a bold or italic font should be used. VALUE
4669 must be t or nil in that case. A value of `unspecified' is not allowed."
4670
4671 Please see also the documentation of `set-face-attribute' and
4672 `defface'.
4673
4674 `:inherit'
4675
4676 VALUE is the name of a face from which to inherit attributes, or a list
4677 of face names. Attributes from inherited faces are merged into the face
4678 like an underlying face would be, with higher priority than underlying faces.
4679
4680 *** Face attributes and X resources
4681
4682 The following X resource names can be used to set face attributes
4683 from X resources:
4684
4685 Face attribute X resource class
4686 -----------------------------------------------------------------------
4687 :family attributeFamily . Face.AttributeFamily
4688 :width attributeWidth Face.AttributeWidth
4689 :height attributeHeight Face.AttributeHeight
4690 :weight attributeWeight Face.AttributeWeight
4691 :slant attributeSlant Face.AttributeSlant
4692 foreground attributeForeground Face.AttributeForeground
4693 :background attributeBackground . Face.AttributeBackground
4694 :overline attributeOverline Face.AttributeOverline
4695 :strike-through attributeStrikeThrough Face.AttributeStrikeThrough
4696 :box attributeBox Face.AttributeBox
4697 :underline attributeUnderline Face.AttributeUnderline
4698 :inverse-video attributeInverse Face.AttributeInverse
4699 :stipple attributeStipple Face.AttributeStipple
4700 or attributeBackgroundPixmap
4701 Face.AttributeBackgroundPixmap
4702 :font attributeFont Face.AttributeFont
4703 :bold attributeBold Face.AttributeBold
4704 :italic attributeItalic . Face.AttributeItalic
4705 :font attributeFont Face.AttributeFont
4706
4707 *** Text property `face'.
4708
4709 The value of the `face' text property can now be a single face
4710 specification or a list of such specifications. Each face
4711 specification can be
4712
4713 1. A symbol or string naming a Lisp face.
4714
4715 2. A property list of the form (KEYWORD VALUE ...) where each
4716 KEYWORD is a face attribute name, and VALUE is an appropriate value
4717 for that attribute. Please see the doc string of `set-face-attribute'
4718 for face attribute names.
4719
4720 3. Conses of the form (FOREGROUND-COLOR . COLOR) or
4721 (BACKGROUND-COLOR . COLOR) where COLOR is a color name. This is
4722 for compatibility with previous Emacs versions.
4723
4724 ** Support functions for colors on text-only terminals.
4725
4726 The function `tty-color-define' can be used to define colors for use
4727 on TTY and MSDOS frames. It maps a color name to a color number on
4728 the terminal. Emacs defines a couple of common color mappings by
4729 default. You can get defined colors with a call to
4730 `defined-colors'. The function `tty-color-clear' can be
4731 used to clear the mapping table.
4732
4733 ** Unified support for colors independent of frame type.
4734
4735 The new functions `defined-colors', `color-defined-p', `color-values',
4736 and `display-color-p' work for any type of frame. On frames whose
4737 type is neither x nor w32, these functions transparently map X-style
4738 color specifications to the closest colors supported by the frame
4739 display. Lisp programs should use these new functions instead of the
4740 old `x-defined-colors', `x-color-defined-p', `x-color-values', and
4741 `x-display-color-p'. (The old function names are still available for
4742 compatibility; they are now aliases of the new names.) Lisp programs
4743 should no more look at the value of the variable window-system to
4744 modify their color-related behavior.
4745
4746 The primitives `color-gray-p' and `color-supported-p' also work for
4747 any frame type.
4748
4749 ** Platform-independent functions to describe display capabilities.
4750
4751 The new functions `display-mouse-p', `display-popup-menus-p',
4752 `display-graphic-p', `display-selections-p', `display-screens',
4753 `display-pixel-width', `display-pixel-height', `display-mm-width',
4754 `display-mm-height', `display-backing-store', `display-save-under',
4755 `display-planes', `display-color-cells', `display-visual-class', and
4756 `display-grayscale-p' describe the basic capabilities of a particular
4757 display. Lisp programs should call these functions instead of testing
4758 the value of the variables `window-system' or `system-type', or calling
4759 platform-specific functions such as `x-display-pixel-width'.
4760
4761 The new function `display-images-p' returns non-nil if a particular
4762 display can display image files.
4763
4764 ** The minibuffer prompt is now actually inserted in the minibuffer.
4765
4766 This makes it possible to scroll through the prompt, if you want to.
4767 To disallow this completely (like previous versions of emacs), customize
4768 the variable `minibuffer-prompt-properties', and turn on the
4769 `Inviolable' option.
4770
4771 The function `minibuffer-prompt-end' returns the current position of the
4772 end of the minibuffer prompt, if the minibuffer is current.
4773 Otherwise, it returns `(point-min)'.
4774
4775 ** New `field' abstraction in buffers.
4776
4777 There is now code to support an abstraction called `fields' in emacs
4778 buffers. A field is a contiguous region of text with the same `field'
4779 property (which can be a text property or an overlay).
4780
4781 Many emacs functions, such as forward-word, forward-sentence,
4782 forward-paragraph, beginning-of-line, etc., stop moving when they come
4783 to the boundary between fields; beginning-of-line and end-of-line will
4784 not let the point move past the field boundary, but other movement
4785 commands continue into the next field if repeated. Stopping at field
4786 boundaries can be suppressed programmatically by binding
4787 `inhibit-field-text-motion' to a non-nil value around calls to these
4788 functions.
4789
4790 Now that the minibuffer prompt is inserted into the minibuffer, it is in
4791 a separate field from the user-input part of the buffer, so that common
4792 editing commands treat the user's text separately from the prompt.
4793
4794 The following functions are defined for operating on fields:
4795
4796 - Function: constrain-to-field NEW-POS OLD-POS &optional ESCAPE-FROM-EDGE ONLY-IN-LINE INHIBIT-CAPTURE-PROPERTY
4797
4798 Return the position closest to NEW-POS that is in the same field as OLD-POS.
4799
4800 A field is a region of text with the same `field' property.
4801 If NEW-POS is nil, then the current point is used instead, and set to the
4802 constrained position if that is different.
4803
4804 If OLD-POS is at the boundary of two fields, then the allowable
4805 positions for NEW-POS depends on the value of the optional argument
4806 ESCAPE-FROM-EDGE: If ESCAPE-FROM-EDGE is nil, then NEW-POS is
4807 constrained to the field that has the same `field' char-property
4808 as any new characters inserted at OLD-POS, whereas if ESCAPE-FROM-EDGE
4809 is non-nil, NEW-POS is constrained to the union of the two adjacent
4810 fields. Additionally, if two fields are separated by another field with
4811 the special value `boundary', then any point within this special field is
4812 also considered to be `on the boundary'.
4813
4814 If the optional argument ONLY-IN-LINE is non-nil and constraining
4815 NEW-POS would move it to a different line, NEW-POS is returned
4816 unconstrained. This useful for commands that move by line, like
4817 C-n or C-a, which should generally respect field boundaries
4818 only in the case where they can still move to the right line.
4819
4820 If the optional argument INHIBIT-CAPTURE-PROPERTY is non-nil, and OLD-POS has
4821 a non-nil property of that name, then any field boundaries are ignored.
4822
4823 Field boundaries are not noticed if `inhibit-field-text-motion' is non-nil.
4824
4825 - Function: delete-field &optional POS
4826
4827 Delete the field surrounding POS.
4828 A field is a region of text with the same `field' property.
4829 If POS is nil, the value of point is used for POS.
4830
4831 - Function: field-beginning &optional POS ESCAPE-FROM-EDGE
4832
4833 Return the beginning of the field surrounding POS.
4834 A field is a region of text with the same `field' property.
4835 If POS is nil, the value of point is used for POS.
4836 If ESCAPE-FROM-EDGE is non-nil and POS is at the beginning of its
4837 field, then the beginning of the *previous* field is returned.
4838
4839 - Function: field-end &optional POS ESCAPE-FROM-EDGE
4840
4841 Return the end of the field surrounding POS.
4842 A field is a region of text with the same `field' property.
4843 If POS is nil, the value of point is used for POS.
4844 If ESCAPE-FROM-EDGE is non-nil and POS is at the end of its field,
4845 then the end of the *following* field is returned.
4846
4847 - Function: field-string &optional POS
4848
4849 Return the contents of the field surrounding POS as a string.
4850 A field is a region of text with the same `field' property.
4851 If POS is nil, the value of point is used for POS.
4852
4853 - Function: field-string-no-properties &optional POS
4854
4855 Return the contents of the field around POS, without text-properties.
4856 A field is a region of text with the same `field' property.
4857 If POS is nil, the value of point is used for POS.
4858
4859 ** Image support.
4860
4861 Emacs can now display images. Images are inserted into text by giving
4862 strings or buffer text a `display' text property containing one of
4863 (AREA IMAGE) or IMAGE. The display of the `display' property value
4864 replaces the display of the characters having that property.
4865
4866 If the property value has the form (AREA IMAGE), AREA must be one of
4867 `(margin left-margin)', `(margin right-margin)' or `(margin nil)'. If
4868 AREA is `(margin nil)', IMAGE will be displayed in the text area of a
4869 window, otherwise it will be displayed in the left or right marginal
4870 area.
4871
4872 IMAGE is an image specification.
4873
4874 *** Image specifications
4875
4876 Image specifications are lists of the form `(image PROPS)' where PROPS
4877 is a property list whose keys are keyword symbols. Each
4878 specifications must contain a property `:type TYPE' with TYPE being a
4879 symbol specifying the image type, e.g. `xbm'. Properties not
4880 described below are ignored.
4881
4882 The following is a list of properties all image types share.
4883
4884 `:ascent ASCENT'
4885
4886 ASCENT must be a number in the range 0..100, or the symbol `center'.
4887 If it is a number, it specifies the percentage of the image's height
4888 to use for its ascent.
4889
4890 If not specified, ASCENT defaults to the value 50 which means that the
4891 image will be centered with the base line of the row it appears in.
4892
4893 If ASCENT is `center' the image is vertically centered around a
4894 centerline which is the vertical center of text drawn at the position
4895 of the image, in the manner specified by the text properties and
4896 overlays that apply to the image.
4897
4898 `:margin MARGIN'
4899
4900 MARGIN must be either a number >= 0 specifying how many pixels to put
4901 as margin around the image, or a pair (X . Y) with X specifying the
4902 horizontal margin and Y specifying the vertical margin. Default is 0.
4903
4904 `:relief RELIEF'
4905
4906 RELIEF is analogous to the `:relief' attribute of faces. Puts a relief
4907 around an image.
4908
4909 `:conversion ALGO'
4910
4911 Apply an image algorithm to the image before displaying it.
4912
4913 ALGO `laplace' or `emboss' means apply a Laplace or ``emboss''
4914 edge-detection algorithm to the image.
4915
4916 ALGO `(edge-detection :matrix MATRIX :color-adjust ADJUST)' means
4917 apply a general edge-detection algorithm. MATRIX must be either a
4918 nine-element list or a nine-element vector of numbers. A pixel at
4919 position x/y in the transformed image is computed from original pixels
4920 around that position. MATRIX specifies, for each pixel in the
4921 neighborhood of x/y, a factor with which that pixel will influence the
4922 transformed pixel; element 0 specifies the factor for the pixel at
4923 x-1/y-1, element 1 the factor for the pixel at x/y-1 etc. as shown
4924 below.
4925
4926 (x-1/y-1 x/y-1 x+1/y-1
4927 x-1/y x/y x+1/y
4928 x-1/y+1 x/y+1 x+1/y+1)
4929
4930 The resulting pixel is computed from the color intensity of the color
4931 resulting from summing up the RGB values of surrounding pixels,
4932 multiplied by the specified factors, and dividing that sum by the sum
4933 of the factors' absolute values.
4934
4935 Laplace edge-detection currently uses a matrix of
4936
4937 (1 0 0
4938 0 0 0
4939 9 9 -1)
4940
4941 Emboss edge-detection uses a matrix of
4942
4943 ( 2 -1 0
4944 -1 0 1
4945 0 1 -2)
4946
4947 ALGO `disabled' means transform the image so that it looks
4948 ``disabled''.
4949
4950 `:mask MASK'
4951
4952 If MASK is `heuristic' or `(heuristic BG)', build a clipping mask for
4953 the image, so that the background of a frame is visible behind the
4954 image. If BG is not specified, or if BG is t, determine the
4955 background color of the image by looking at the 4 corners of the
4956 image, assuming the most frequently occurring color from the corners is
4957 the background color of the image. Otherwise, BG must be a list `(RED
4958 GREEN BLUE)' specifying the color to assume for the background of the
4959 image.
4960
4961 If MASK is nil, remove a mask from the image, if it has one. Images
4962 in some formats include a mask which can be removed by specifying
4963 `:mask nil'.
4964
4965 `:file FILE'
4966
4967 Load image from FILE. If FILE is not absolute after expanding it,
4968 search for the image in `data-directory'. Some image types support
4969 building images from data. When this is done, no `:file' property
4970 may be present in the image specification.
4971
4972 `:data DATA'
4973
4974 Get image data from DATA. (As of this writing, this is not yet
4975 supported for image type `postscript'). Either :file or :data may be
4976 present in an image specification, but not both. All image types
4977 support strings as DATA, some types allow additional types of DATA.
4978
4979 *** Supported image types
4980
4981 **** XBM, image type `xbm'.
4982
4983 XBM images don't require an external library. Additional image
4984 properties supported are
4985
4986 `:foreground FG'
4987
4988 FG must be a string specifying the image foreground color, or nil
4989 meaning to use the default. Default is the frame's foreground.
4990
4991 `:background BG'
4992
4993 BG must be a string specifying the image foreground color, or nil
4994 meaning to use the default. Default is the frame's background color.
4995
4996 XBM images can be constructed from data instead of file. In this
4997 case, the image specification must contain the following properties
4998 instead of a `:file' property.
4999
5000 `:width WIDTH'
5001
5002 WIDTH specifies the width of the image in pixels.
5003
5004 `:height HEIGHT'
5005
5006 HEIGHT specifies the height of the image in pixels.
5007
5008 `:data DATA'
5009
5010 DATA must be either
5011
5012 1. a string large enough to hold the bitmap data, i.e. it must
5013 have a size >= (WIDTH + 7) / 8 * HEIGHT
5014
5015 2. a bool-vector of size >= WIDTH * HEIGHT
5016
5017 3. a vector of strings or bool-vectors, one for each line of the
5018 bitmap.
5019
5020 4. a string that's an in-memory XBM file. Neither width nor
5021 height may be specified in this case because these are defined
5022 in the file.
5023
5024 **** XPM, image type `xpm'
5025
5026 XPM images require the external library `libXpm', package
5027 `xpm-3.4k.tar.gz', version 3.4k or later. Make sure the library is
5028 found when Emacs is configured by supplying appropriate paths via
5029 `--x-includes' and `--x-libraries'.
5030
5031 Additional image properties supported are:
5032
5033 `:color-symbols SYMBOLS'
5034
5035 SYMBOLS must be a list of pairs (NAME . COLOR), with NAME being the
5036 name of color as it appears in an XPM file, and COLOR being an X color
5037 name.
5038
5039 XPM images can be built from memory instead of files. In that case,
5040 add a `:data' property instead of a `:file' property.
5041
5042 The XPM library uses libz in its implementation so that it is able
5043 to display compressed images.
5044
5045 **** PBM, image type `pbm'
5046
5047 PBM images don't require an external library. Color, gray-scale and
5048 mono images are supported. Additional image properties supported for
5049 mono images are
5050
5051 `:foreground FG'
5052
5053 FG must be a string specifying the image foreground color, or nil
5054 meaning to use the default. Default is the frame's foreground.
5055
5056 `:background FG'
5057
5058 BG must be a string specifying the image foreground color, or nil
5059 meaning to use the default. Default is the frame's background color.
5060
5061 **** JPEG, image type `jpeg'
5062
5063 Support for JPEG images requires the external library `libjpeg',
5064 package `jpegsrc.v6a.tar.gz', or later. Additional image properties
5065 are:
5066
5067 **** TIFF, image type `tiff'
5068
5069 Support for TIFF images requires the external library `libtiff',
5070 package `tiff-v3.4-tar.gz', or later. There are no additional image
5071 properties defined.
5072
5073 **** GIF, image type `gif'
5074
5075 Support for GIF images requires the external library `libungif', package
5076 `libungif-4.1.0', or later.
5077
5078 Additional image properties supported are:
5079
5080 `:index INDEX'
5081
5082 INDEX must be an integer >= 0. Load image number INDEX from a
5083 multi-image GIF file. An error is signaled if INDEX is too large.
5084
5085 This could be used to implement limited support for animated GIFs.
5086 For example, the following function displays a multi-image GIF file
5087 at point-min in the current buffer, switching between sub-images
5088 every 0.1 seconds.
5089
5090 (defun show-anim (file max)
5091 "Display multi-image GIF file FILE which contains MAX subimages."
5092 (display-anim (current-buffer) file 0 max t))
5093
5094 (defun display-anim (buffer file idx max first-time)
5095 (when (= idx max)
5096 (setq idx 0))
5097 (let ((img (create-image file nil nil :index idx)))
5098 (save-excursion
5099 (set-buffer buffer)
5100 (goto-char (point-min))
5101 (unless first-time (delete-char 1))
5102 (insert-image img "x"))
5103 (run-with-timer 0.1 nil 'display-anim buffer file (1+ idx) max nil)))
5104
5105 **** PNG, image type `png'
5106
5107 Support for PNG images requires the external library `libpng',
5108 package `libpng-1.0.2.tar.gz', or later. There are no additional image
5109 properties defined.
5110
5111 **** Ghostscript, image type `postscript'.
5112
5113 Additional image properties supported are:
5114
5115 `:pt-width WIDTH'
5116
5117 WIDTH is width of the image in pt (1/72 inch). WIDTH must be an
5118 integer. This is a required property.
5119
5120 `:pt-height HEIGHT'
5121
5122 HEIGHT specifies the height of the image in pt (1/72 inch). HEIGHT
5123 must be a integer. This is an required property.
5124
5125 `:bounding-box BOX'
5126
5127 BOX must be a list or vector of 4 integers giving the bounding box of
5128 the PS image, analogous to the `BoundingBox' comment found in PS
5129 files. This is an required property.
5130
5131 Part of the Ghostscript interface is implemented in Lisp. See
5132 lisp/gs.el.
5133
5134 *** Lisp interface.
5135
5136 The variable `image-types' contains a list of those image types
5137 which are supported in the current configuration.
5138
5139 Images are stored in an image cache and removed from the cache when
5140 they haven't been displayed for `image-cache-eviction-delay seconds.
5141 The function `clear-image-cache' can be used to clear the image cache
5142 manually. Images in the cache are compared with `equal', i.e. all
5143 images with `equal' specifications share the same image.
5144
5145 *** Simplified image API, image.el
5146
5147 The new Lisp package image.el contains functions that simplify image
5148 creation and putting images into text. The function `create-image'
5149 can be used to create images. The macro `defimage' can be used to
5150 define an image based on available image types. The functions
5151 `put-image' and `insert-image' can be used to insert an image into a
5152 buffer.
5153
5154 ** Display margins.
5155
5156 Windows can now have margins which are used for special text
5157 and images.
5158
5159 To give a window margins, either set the buffer-local variables
5160 `left-margin-width' and `right-margin-width', or call
5161 `set-window-margins'. The function `window-margins' can be used to
5162 obtain the current settings. To make `left-margin-width' and
5163 `right-margin-width' take effect, you must set them before displaying
5164 the buffer in a window, or use `set-window-buffer' to force an update
5165 of the display margins.
5166
5167 You can put text in margins by giving it a `display' text property
5168 containing a pair of the form `(LOCATION . VALUE)', where LOCATION is
5169 one of `left-margin' or `right-margin' or nil. VALUE can be either a
5170 string, an image specification or a stretch specification (see later
5171 in this file).
5172
5173 ** Help display
5174
5175 Emacs displays short help messages in the echo area, when the mouse
5176 moves over a tool-bar item or a piece of text that has a text property
5177 `help-echo'. This feature also applies to strings in the mode line
5178 that have a `help-echo' property.
5179
5180 If the value of the `help-echo' property is a function, that function
5181 is called with three arguments WINDOW, OBJECT and POSITION. WINDOW is
5182 the window in which the help was found.
5183
5184 If OBJECT is a buffer, POS is the position in the buffer where the
5185 `help-echo' text property was found.
5186
5187 If OBJECT is an overlay, that overlay has a `help-echo' property, and
5188 POS is the position in the overlay's buffer under the mouse.
5189
5190 If OBJECT is a string (an overlay string or a string displayed with
5191 the `display' property), POS is the position in that string under the
5192 mouse.
5193
5194 If the value of the `help-echo' property is neither a function nor a
5195 string, it is evaluated to obtain a help string.
5196
5197 For tool-bar and menu-bar items, their key definition is used to
5198 determine the help to display. If their definition contains a
5199 property `:help FORM', FORM is evaluated to determine the help string.
5200 For tool-bar items without a help form, the caption of the item is
5201 used as help string.
5202
5203 The hook `show-help-function' can be set to a function that displays
5204 the help string differently. For example, enabling a tooltip window
5205 causes the help display to appear there instead of in the echo area.
5206
5207 ** Vertical fractional scrolling.
5208
5209 The display of text in windows can be scrolled smoothly in pixels.
5210 This is useful, for example, for making parts of large images visible.
5211
5212 The function `window-vscroll' returns the current value of vertical
5213 scrolling, a non-negative fraction of the canonical character height.
5214 The function `set-window-vscroll' can be used to set the vertical
5215 scrolling value. Here is an example of how these function might be
5216 used.
5217
5218 (global-set-key [A-down]
5219 #'(lambda ()
5220 (interactive)
5221 (set-window-vscroll (selected-window)
5222 (+ 0.5 (window-vscroll)))))
5223 (global-set-key [A-up]
5224 #'(lambda ()
5225 (interactive)
5226 (set-window-vscroll (selected-window)
5227 (- (window-vscroll) 0.5)))))
5228
5229 ** New hook `fontification-functions'.
5230
5231 Functions from `fontification-functions' are called from redisplay
5232 when it encounters a region of text that is not yet fontified. This
5233 variable automatically becomes buffer-local when set. Each function
5234 is called with one argument, POS.
5235
5236 At least one of the hook functions should fontify one or more
5237 characters starting at POS in the current buffer. It should mark them
5238 as fontified by giving them a non-nil value of the `fontified' text
5239 property. It may be reasonable for these functions to check for the
5240 `fontified' property and not put it back on, but they do not have to.
5241
5242 ** Tool bar support.
5243
5244 Emacs supports a tool bar at the top of a frame under X. The frame
5245 parameter `tool-bar-lines' (X resource "toolBar", class "ToolBar")
5246 controls how may lines to reserve for the tool bar. A zero value
5247 suppresses the tool bar. If the value is non-zero and
5248 `auto-resize-tool-bars' is non-nil the tool bar's size will be changed
5249 automatically so that all tool bar items are visible.
5250
5251 *** Tool bar item definitions
5252
5253 Tool bar items are defined using `define-key' with a prefix-key
5254 `tool-bar'. For example `(define-key global-map [tool-bar item1] ITEM)'
5255 where ITEM is a list `(menu-item CAPTION BINDING PROPS...)'.
5256
5257 CAPTION is the caption of the item, If it's not a string, it is
5258 evaluated to get a string. The caption is currently not displayed in
5259 the tool bar, but it is displayed if the item doesn't have a `:help'
5260 property (see below).
5261
5262 BINDING is the tool bar item's binding. Tool bar items with keymaps as
5263 binding are currently ignored.
5264
5265 The following properties are recognized:
5266
5267 `:enable FORM'.
5268
5269 FORM is evaluated and specifies whether the tool bar item is enabled
5270 or disabled.
5271
5272 `:visible FORM'
5273
5274 FORM is evaluated and specifies whether the tool bar item is displayed.
5275
5276 `:filter FUNCTION'
5277
5278 FUNCTION is called with one parameter, the same list BINDING in which
5279 FUNCTION is specified as the filter. The value FUNCTION returns is
5280 used instead of BINDING to display this item.
5281
5282 `:button (TYPE SELECTED)'
5283
5284 TYPE must be one of `:radio' or `:toggle'. SELECTED is evaluated
5285 and specifies whether the button is selected (pressed) or not.
5286
5287 `:image IMAGES'
5288
5289 IMAGES is either a single image specification or a vector of four
5290 image specifications. If it is a vector, this table lists the
5291 meaning of each of the four elements:
5292
5293 Index Use when item is
5294 ----------------------------------------
5295 0 enabled and selected
5296 1 enabled and deselected
5297 2 disabled and selected
5298 3 disabled and deselected
5299
5300 If IMAGE is a single image specification, a Laplace edge-detection
5301 algorithm is used on that image to draw the image in disabled state.
5302
5303 `:help HELP-STRING'.
5304
5305 Gives a help string to display for the tool bar item. This help
5306 is displayed when the mouse is moved over the item.
5307
5308 The function `toolbar-add-item' is a convenience function for adding
5309 toolbar items generally, and `tool-bar-add-item-from-menu' can be used
5310 to define a toolbar item with a binding copied from an item on the
5311 menu bar.
5312
5313 The default bindings use a menu-item :filter to derive the tool-bar
5314 dynamically from variable `tool-bar-map' which may be set
5315 buffer-locally to override the global map.
5316
5317 *** Tool-bar-related variables.
5318
5319 If `auto-resize-tool-bar' is non-nil, the tool bar will automatically
5320 resize to show all defined tool bar items. It will never grow larger
5321 than 1/4 of the frame's size.
5322
5323 If `auto-raise-tool-bar-buttons' is non-nil, tool bar buttons will be
5324 raised when the mouse moves over them.
5325
5326 You can add extra space between tool bar items by setting
5327 `tool-bar-button-margin' to a positive integer specifying a number of
5328 pixels, or a pair of integers (X . Y) specifying horizontal and
5329 vertical margins . Default is 1.
5330
5331 You can change the shadow thickness of tool bar buttons by setting
5332 `tool-bar-button-relief' to an integer. Default is 3.
5333
5334 *** Tool-bar clicks with modifiers.
5335
5336 You can bind commands to clicks with control, shift, meta etc. on
5337 a tool bar item. If
5338
5339 (define-key global-map [tool-bar shell]
5340 '(menu-item "Shell" shell
5341 :image (image :type xpm :file "shell.xpm")))
5342
5343 is the original tool bar item definition, then
5344
5345 (define-key global-map [tool-bar S-shell] 'some-command)
5346
5347 makes a binding to run `some-command' for a shifted click on the same
5348 item.
5349
5350 ** Mode line changes.
5351
5352 *** Mouse-sensitive mode line.
5353
5354 The mode line can be made mouse-sensitive by displaying strings there
5355 that have a `local-map' text property. There are three ways to display
5356 a string with a `local-map' property in the mode line.
5357
5358 1. The mode line spec contains a variable whose string value has
5359 a `local-map' text property.
5360
5361 2. The mode line spec contains a format specifier (e.g. `%12b'), and
5362 that format specifier has a `local-map' property.
5363
5364 3. The mode line spec contains a list containing `:eval FORM'. FORM
5365 is evaluated. If the result is a string, and that string has a
5366 `local-map' property.
5367
5368 The same mechanism is used to determine the `face' and `help-echo'
5369 properties of strings in the mode line. See `bindings.el' for an
5370 example.
5371
5372 *** If a mode line element has the form `(:eval FORM)', FORM is
5373 evaluated and the result is used as mode line element.
5374
5375 *** You can suppress mode-line display by setting the buffer-local
5376 variable mode-line-format to nil.
5377
5378 *** A headerline can now be displayed at the top of a window.
5379
5380 This mode line's contents are controlled by the new variable
5381 `header-line-format' and `default-header-line-format' which are
5382 completely analogous to `mode-line-format' and
5383 `default-mode-line-format'. A value of nil means don't display a top
5384 line.
5385
5386 The appearance of top mode lines is controlled by the face
5387 `header-line'.
5388
5389 The function `coordinates-in-window-p' returns `header-line' for a
5390 position in the header-line.
5391
5392 ** Text property `display'
5393
5394 The `display' text property is used to insert images into text,
5395 replace text with other text, display text in marginal area, and it is
5396 also used to control other aspects of how text displays. The value of
5397 the `display' property should be a display specification, as described
5398 below, or a list or vector containing display specifications.
5399
5400 *** Replacing text, displaying text in marginal areas
5401
5402 To replace the text having the `display' property with some other
5403 text, use a display specification of the form `(LOCATION STRING)'.
5404
5405 If LOCATION is `(margin left-margin)', STRING is displayed in the left
5406 marginal area, if it is `(margin right-margin)', it is displayed in
5407 the right marginal area, and if LOCATION is `(margin nil)' STRING
5408 is displayed in the text. In the latter case you can also use the
5409 simpler form STRING as property value.
5410
5411 *** Variable width and height spaces
5412
5413 To display a space of fractional width or height, use a display
5414 specification of the form `(LOCATION STRECH)'. If LOCATION is
5415 `(margin left-margin)', the space is displayed in the left marginal
5416 area, if it is `(margin right-margin)', it is displayed in the right
5417 marginal area, and if LOCATION is `(margin nil)' the space is
5418 displayed in the text. In the latter case you can also use the
5419 simpler form STRETCH as property value.
5420
5421 The stretch specification STRETCH itself is a list of the form `(space
5422 PROPS)', where PROPS is a property list which can contain the
5423 properties described below.
5424
5425 The display of the fractional space replaces the display of the
5426 characters having the `display' property.
5427
5428 - :width WIDTH
5429
5430 Specifies that the space width should be WIDTH times the normal
5431 character width. WIDTH can be an integer or floating point number.
5432
5433 - :relative-width FACTOR
5434
5435 Specifies that the width of the stretch should be computed from the
5436 first character in a group of consecutive characters that have the
5437 same `display' property. The computation is done by multiplying the
5438 width of that character by FACTOR.
5439
5440 - :align-to HPOS
5441
5442 Specifies that the space should be wide enough to reach HPOS. The
5443 value HPOS is measured in units of the normal character width.
5444
5445 Exactly one of the above properties should be used.
5446
5447 - :height HEIGHT
5448
5449 Specifies the height of the space, as HEIGHT, measured in terms of the
5450 normal line height.
5451
5452 - :relative-height FACTOR
5453
5454 The height of the space is computed as the product of the height
5455 of the text having the `display' property and FACTOR.
5456
5457 - :ascent ASCENT
5458
5459 Specifies that ASCENT percent of the height of the stretch should be
5460 used for the ascent of the stretch, i.e. for the part above the
5461 baseline. The value of ASCENT must be a non-negative number less or
5462 equal to 100.
5463
5464 You should not use both `:height' and `:relative-height' together.
5465
5466 *** Images
5467
5468 A display specification for an image has the form `(LOCATION
5469 . IMAGE)', where IMAGE is an image specification. The image replaces,
5470 in the display, the characters having this display specification in
5471 their `display' text property. If LOCATION is `(margin left-margin)',
5472 the image will be displayed in the left marginal area, if it is
5473 `(margin right-margin)' it will be displayed in the right marginal
5474 area, and if LOCATION is `(margin nil)' the image will be displayed in
5475 the text. In the latter case you can also use the simpler form IMAGE
5476 as display specification.
5477
5478 *** Other display properties
5479
5480 - (space-width FACTOR)
5481
5482 Specifies that space characters in the text having that property
5483 should be displayed FACTOR times as wide as normal; FACTOR must be an
5484 integer or float.
5485
5486 - (height HEIGHT)
5487
5488 Display text having this property in a font that is smaller or larger.
5489
5490 If HEIGHT is a list of the form `(+ N)', where N is an integer, that
5491 means to use a font that is N steps larger. If HEIGHT is a list of
5492 the form `(- N)', that means to use a font that is N steps smaller. A
5493 ``step'' is defined by the set of available fonts; each size for which
5494 a font is available counts as a step.
5495
5496 If HEIGHT is a number, that means to use a font that is HEIGHT times
5497 as tall as the frame's default font.
5498
5499 If HEIGHT is a symbol, it is called as a function with the current
5500 height as argument. The function should return the new height to use.
5501
5502 Otherwise, HEIGHT is evaluated to get the new height, with the symbol
5503 `height' bound to the current specified font height.
5504
5505 - (raise FACTOR)
5506
5507 FACTOR must be a number, specifying a multiple of the current
5508 font's height. If it is positive, that means to display the characters
5509 raised. If it is negative, that means to display them lower down. The
5510 amount of raising or lowering is computed without taking account of the
5511 `height' subproperty.
5512
5513 *** Conditional display properties
5514
5515 All display specifications can be conditionalized. If a specification
5516 has the form `(when CONDITION . SPEC)', the specification SPEC applies
5517 only when CONDITION yields a non-nil value when evaluated. During the
5518 evaluation, `object' is bound to the string or buffer having the
5519 conditional display property; `position' and `buffer-position' are
5520 bound to the position within `object' and the buffer position where
5521 the display property was found, respectively. Both positions can be
5522 different when object is a string.
5523
5524 The normal specification consisting of SPEC only is equivalent to
5525 `(when t . SPEC)'.
5526
5527 ** New menu separator types.
5528
5529 Emacs now supports more than one menu separator type. Menu items with
5530 item names consisting of dashes only (including zero dashes) are
5531 treated like before. In addition, the following item names are used
5532 to specify other menu separator types.
5533
5534 - `--no-line' or `--space', or `--:space', or `--:noLine'
5535
5536 No separator lines are drawn, but a small space is inserted where the
5537 separator occurs.
5538
5539 - `--single-line' or `--:singleLine'
5540
5541 A single line in the menu's foreground color.
5542
5543 - `--double-line' or `--:doubleLine'
5544
5545 A double line in the menu's foreground color.
5546
5547 - `--single-dashed-line' or `--:singleDashedLine'
5548
5549 A single dashed line in the menu's foreground color.
5550
5551 - `--double-dashed-line' or `--:doubleDashedLine'
5552
5553 A double dashed line in the menu's foreground color.
5554
5555 - `--shadow-etched-in' or `--:shadowEtchedIn'
5556
5557 A single line with 3D sunken appearance. This is the form
5558 displayed for item names consisting of dashes only.
5559
5560 - `--shadow-etched-out' or `--:shadowEtchedOut'
5561
5562 A single line with 3D raised appearance.
5563
5564 - `--shadow-etched-in-dash' or `--:shadowEtchedInDash'
5565
5566 A single dashed line with 3D sunken appearance.
5567
5568 - `--shadow-etched-out-dash' or `--:shadowEtchedOutDash'
5569
5570 A single dashed line with 3D raise appearance.
5571
5572 - `--shadow-double-etched-in' or `--:shadowDoubleEtchedIn'
5573
5574 Two lines with 3D sunken appearance.
5575
5576 - `--shadow-double-etched-out' or `--:shadowDoubleEtchedOut'
5577
5578 Two lines with 3D raised appearance.
5579
5580 - `--shadow-double-etched-in-dash' or `--:shadowDoubleEtchedInDash'
5581
5582 Two dashed lines with 3D sunken appearance.
5583
5584 - `--shadow-double-etched-out-dash' or `--:shadowDoubleEtchedOutDash'
5585
5586 Two dashed lines with 3D raised appearance.
5587
5588 Under LessTif/Motif, the last four separator types are displayed like
5589 the corresponding single-line separators.
5590
5591 ** New frame parameters for scroll bar colors.
5592
5593 The new frame parameters `scroll-bar-foreground' and
5594 `scroll-bar-background' can be used to change scroll bar colors.
5595 Their value must be either a color name, a string, or nil to specify
5596 that scroll bars should use a default color. For toolkit scroll bars,
5597 default colors are toolkit specific. For non-toolkit scroll bars, the
5598 default background is the background color of the frame, and the
5599 default foreground is black.
5600
5601 The X resource name of these parameters are `scrollBarForeground'
5602 (class ScrollBarForeground) and `scrollBarBackground' (class
5603 `ScrollBarBackground').
5604
5605 Setting these parameters overrides toolkit specific X resource
5606 settings for scroll bar colors.
5607
5608 ** You can set `redisplay-dont-pause' to a non-nil value to prevent
5609 display updates from being interrupted when input is pending.
5610
5611 ** Changing a window's width may now change its window start if it
5612 starts on a continuation line. The new window start is computed based
5613 on the window's new width, starting from the start of the continued
5614 line as the start of the screen line with the minimum distance from
5615 the original window start.
5616
5617 ** The variable `hscroll-step' and the functions
5618 `hscroll-point-visible' and `hscroll-window-column' have been removed
5619 now that proper horizontal scrolling is implemented.
5620
5621 ** Windows can now be made fixed-width and/or fixed-height.
5622
5623 A window is fixed-size if its buffer has a buffer-local variable
5624 `window-size-fixed' whose value is not nil. A value of `height' makes
5625 windows fixed-height, a value of `width' makes them fixed-width, any
5626 other non-nil value makes them both fixed-width and fixed-height.
5627
5628 The following code makes all windows displaying the current buffer
5629 fixed-width and fixed-height.
5630
5631 (set (make-local-variable 'window-size-fixed) t)
5632
5633 A call to enlarge-window on a window gives an error if that window is
5634 fixed-width and it is tried to change the window's width, or if the
5635 window is fixed-height, and it is tried to change its height. To
5636 change the size of a fixed-size window, bind `window-size-fixed'
5637 temporarily to nil, for example
5638
5639 (let ((window-size-fixed nil))
5640 (enlarge-window 10))
5641
5642 Likewise, an attempt to split a fixed-height window vertically,
5643 or a fixed-width window horizontally results in a error.
5644
5645 ** The cursor-type frame parameter is now supported on MS-DOS
5646 terminals. When Emacs starts, it by default changes the cursor shape
5647 to a solid box, as it does on Unix. The `cursor-type' frame parameter
5648 overrides this as it does on Unix, except that the bar cursor is
5649 horizontal rather than vertical (since the MS-DOS display doesn't
5650 support a vertical-bar cursor).
5651
5652
5653 \f
5654 * Emacs 20.7 is a bug-fix release with few user-visible changes
5655
5656 ** It is now possible to use CCL-based coding systems for keyboard
5657 input.
5658
5659 ** ange-ftp now handles FTP security extensions, like Kerberos.
5660
5661 ** Rmail has been extended to recognize more forms of digest messages.
5662
5663 ** Now, most coding systems set in keyboard coding system work not
5664 only for character input, but also in incremental search. The
5665 exceptions are such coding systems that handle 2-byte character sets
5666 (e.g euc-kr, euc-jp) and that use ISO's escape sequence
5667 (e.g. iso-2022-jp). They are ignored in incremental search.
5668
5669 ** Support for Macintosh PowerPC-based machines running GNU/Linux has
5670 been added.
5671
5672 \f
5673 * Emacs 20.6 is a bug-fix release with one user-visible change
5674
5675 ** Support for ARM-based non-RISCiX machines has been added.
5676
5677
5678 \f
5679 * Emacs 20.5 is a bug-fix release with no user-visible changes.
5680
5681 ** Not new, but not mentioned before:
5682 M-w when Transient Mark mode is enabled disables the mark.
5683 \f
5684 * Changes in Emacs 20.4
5685
5686 ** Init file may be called .emacs.el.
5687
5688 You can now call the Emacs init file `.emacs.el'.
5689 Formerly the name had to be `.emacs'. If you use the name
5690 `.emacs.el', you can byte-compile the file in the usual way.
5691
5692 If both `.emacs' and `.emacs.el' exist, the latter file
5693 is the one that is used.
5694
5695 ** shell-command, and shell-command-on-region, now return
5696 the exit code of the command (unless it is asynchronous).
5697 Also, you can specify a place to put the error output,
5698 separate from the command's regular output.
5699 Interactively, the variable shell-command-default-error-buffer
5700 says where to put error output; set it to a buffer name.
5701 In calls from Lisp, an optional argument ERROR-BUFFER specifies
5702 the buffer name.
5703
5704 When you specify a non-nil error buffer (or buffer name), any error
5705 output is inserted before point in that buffer, with \f\n to separate
5706 it from the previous batch of error output. The error buffer is not
5707 cleared, so error output from successive commands accumulates there.
5708
5709 ** Setting the default value of enable-multibyte-characters to nil in
5710 the .emacs file, either explicitly using setq-default, or via Custom,
5711 is now essentially equivalent to using --unibyte: all buffers
5712 created during startup will be made unibyte after loading .emacs.
5713
5714 ** C-x C-f now handles the wildcards * and ? in file names. For
5715 example, typing C-x C-f c*.c RET visits all the files whose names
5716 match c*.c. To visit a file whose name contains * or ?, add the
5717 quoting sequence /: to the beginning of the file name.
5718
5719 ** The M-x commands keep-lines, flush-lines and count-matches
5720 now have the same feature as occur and query-replace:
5721 if the pattern contains any upper case letters, then
5722 they never ignore case.
5723
5724 ** The end-of-line format conversion feature previously mentioned
5725 under `* Emacs 20.1 changes for MS-DOS and MS-Windows' actually
5726 applies to all operating systems. Emacs recognizes from the contents
5727 of a file what convention it uses to separate lines--newline, CRLF, or
5728 just CR--and automatically converts the contents to the normal Emacs
5729 convention (using newline to separate lines) for editing. This is a
5730 part of the general feature of coding system conversion.
5731
5732 If you subsequently save the buffer, Emacs converts the text back to
5733 the same format that was used in the file before.
5734
5735 You can turn off end-of-line conversion by setting the variable
5736 `inhibit-eol-conversion' to non-nil, e.g. with Custom in the MULE group.
5737
5738 ** The character set property `prefered-coding-system' has been
5739 renamed to `preferred-coding-system', for the sake of correct spelling.
5740 This is a fairly internal feature, so few programs should be affected.
5741
5742 ** Mode-line display of end-of-line format is changed.
5743 The indication of the end-of-line format of the file visited by a
5744 buffer is now more explicit when that format is not the usual one for
5745 your operating system. For example, the DOS-style end-of-line format
5746 is displayed as "(DOS)" on Unix and GNU/Linux systems. The usual
5747 end-of-line format is still displayed as a single character (colon for
5748 Unix, backslash for DOS and Windows, and forward slash for the Mac).
5749
5750 The values of the variables eol-mnemonic-unix, eol-mnemonic-dos,
5751 eol-mnemonic-mac, and eol-mnemonic-undecided, which are strings,
5752 control what is displayed in the mode line for each end-of-line
5753 format. You can now customize these variables.
5754
5755 ** In the previous version of Emacs, tar-mode didn't work well if a
5756 filename contained non-ASCII characters. Now this is fixed. Such a
5757 filename is decoded by file-name-coding-system if the default value of
5758 enable-multibyte-characters is non-nil.
5759
5760 ** The command temp-buffer-resize-mode toggles a minor mode
5761 in which temporary buffers (such as help buffers) are given
5762 windows just big enough to hold the whole contents.
5763
5764 ** If you use completion.el, you must now run the function
5765 dynamic-completion-mode to enable it. Just loading the file
5766 doesn't have any effect.
5767
5768 ** In Flyspell mode, the default is now to make just one Ispell process,
5769 not one per buffer.
5770
5771 ** If you use iswitchb but do not call (iswitchb-default-keybindings) to
5772 use the default keybindings, you will need to add the following line:
5773 (add-hook 'minibuffer-setup-hook 'iswitchb-minibuffer-setup)
5774
5775 ** Auto-show mode is no longer enabled just by loading auto-show.el.
5776 To control it, set `auto-show-mode' via Custom or use the
5777 `auto-show-mode' command.
5778
5779 ** Handling of X fonts' ascent/descent parameters has been changed to
5780 avoid redisplay problems. As a consequence, compared with previous
5781 versions the line spacing and frame size now differ with some font
5782 choices, typically increasing by a pixel per line. This change
5783 occurred in version 20.3 but was not documented then.
5784
5785 ** If you select the bar cursor style, it uses the frame's
5786 cursor-color, rather than the cursor foreground pixel.
5787
5788 ** In multibyte mode, Rmail decodes incoming MIME messages using the
5789 character set specified in the message. If you want to disable this
5790 feature, set the variable rmail-decode-mime-charset to nil.
5791
5792 ** Not new, but not mentioned previously in NEWS: when you use #! at
5793 the beginning of a file to make it executable and specify an
5794 interpreter program, Emacs looks on the second line for the -*- mode
5795 and variable specification, as well as on the first line.
5796
5797 ** Support for IBM codepage encoding of non-ASCII characters.
5798
5799 The new command M-x codepage-setup creates a special coding system
5800 that can be used to convert text between a specific IBM codepage and
5801 one of the character sets built into Emacs which matches that
5802 codepage. For example, codepage 850 corresponds to Latin-1 character
5803 set, codepage 855 corresponds to Cyrillic-ISO character set, etc.
5804
5805 Windows codepages 1250, 1251 and some others, where Windows deviates
5806 from the corresponding ISO character set, are also supported.
5807
5808 IBM box-drawing characters and other glyphs which don't have
5809 equivalents in the corresponding ISO character set, are converted to
5810 a character defined by dos-unsupported-char-glyph on MS-DOS, and to
5811 `?' on other systems.
5812
5813 IBM codepages are widely used on MS-DOS and MS-Windows, so this
5814 feature is most useful on those platforms, but it can also be used on
5815 Unix.
5816
5817 Emacs compiled for MS-DOS automatically loads the support for the
5818 current codepage when it starts.
5819
5820 ** Mail changes
5821
5822 *** When mail is sent using compose-mail (C-x m), and if
5823 `mail-send-nonascii' is set to the new default value `mime',
5824 appropriate MIME headers are added. The headers are added only if
5825 non-ASCII characters are present in the body of the mail, and no other
5826 MIME headers are already present. For example, the following three
5827 headers are added if the coding system used in the *mail* buffer is
5828 latin-1:
5829
5830 MIME-version: 1.0
5831 Content-type: text/plain; charset=iso-8859-1
5832 Content-Transfer-Encoding: 8bit
5833
5834 *** The new variable default-sendmail-coding-system specifies the
5835 default way to encode outgoing mail. This has higher priority than
5836 default-buffer-file-coding-system but has lower priority than
5837 sendmail-coding-system and the local value of
5838 buffer-file-coding-system.
5839
5840 You should not set this variable manually. Instead, set
5841 sendmail-coding-system to specify a fixed encoding for all outgoing
5842 mail.
5843
5844 *** When you try to send a message that contains non-ASCII characters,
5845 if the coding system specified by those variables doesn't handle them,
5846 Emacs will ask you to select a suitable coding system while showing a
5847 list of possible coding systems.
5848
5849 ** CC Mode changes
5850
5851 *** c-default-style can now take an association list that maps major
5852 modes to style names. When this variable is an alist, Java mode no
5853 longer hardcodes a setting to "java" style. See the variable's
5854 docstring for details.
5855
5856 *** It's now possible to put a list as the offset on a syntactic
5857 symbol. The list is evaluated recursively until a non-nil offset is
5858 found. This is useful to combine several lineup functions to act in a
5859 prioritized order on a single line. However, none of the supplied
5860 lineup functions use this feature currently.
5861
5862 *** New syntactic symbol catch-clause, which is used on the "catch" and
5863 "finally" lines in try-catch constructs in C++ and Java.
5864
5865 *** New cleanup brace-catch-brace on c-cleanup-list, which does for
5866 "catch" lines what brace-elseif-brace does for "else if" lines.
5867
5868 *** The braces of Java anonymous inner classes are treated separately
5869 from the braces of other classes in auto-newline mode. Two new
5870 symbols inexpr-class-open and inexpr-class-close may be used on
5871 c-hanging-braces-alist to control the automatic newlines used for
5872 anonymous classes.
5873
5874 *** Support for the Pike language added, along with new Pike specific
5875 syntactic symbols: inlambda, lambda-intro-cont
5876
5877 *** Support for Java anonymous classes via new syntactic symbol
5878 inexpr-class. New syntactic symbol inexpr-statement for Pike
5879 support and gcc-style statements inside expressions. New lineup
5880 function c-lineup-inexpr-block.
5881
5882 *** New syntactic symbol brace-entry-open which is used in brace lists
5883 (i.e. static initializers) when a list entry starts with an open
5884 brace. These used to be recognized as brace-list-entry's.
5885 c-electric-brace also recognizes brace-entry-open braces
5886 (brace-list-entry's can no longer be electrified).
5887
5888 *** New command c-indent-line-or-region, not bound by default.
5889
5890 *** `#' is only electric when typed in the indentation of a line.
5891
5892 *** Parentheses are now electric (via the new command c-electric-paren)
5893 for auto-reindenting lines when parens are typed.
5894
5895 *** In "gnu" style, inline-open offset is now set to zero.
5896
5897 *** Uniform handling of the inclass syntactic symbol. The indentation
5898 associated with it is now always relative to the class opening brace.
5899 This means that the indentation behavior has changed in some
5900 circumstances, but only if you've put anything besides 0 on the
5901 class-open syntactic symbol (none of the default styles do that).
5902
5903 ** Gnus changes.
5904
5905 *** New functionality for using Gnus as an offline newsreader has been
5906 added. A plethora of new commands and modes have been added. See the
5907 Gnus manual for the full story.
5908
5909 *** The nndraft backend has returned, but works differently than
5910 before. All Message buffers are now also articles in the nndraft
5911 group, which is created automatically.
5912
5913 *** `gnus-alter-header-function' can now be used to alter header
5914 values.
5915
5916 *** `gnus-summary-goto-article' now accept Message-ID's.
5917
5918 *** A new Message command for deleting text in the body of a message
5919 outside the region: `C-c C-v'.
5920
5921 *** You can now post to component group in nnvirtual groups with
5922 `C-u C-c C-c'.
5923
5924 *** `nntp-rlogin-program' -- new variable to ease customization.
5925
5926 *** `C-u C-c C-c' in `gnus-article-edit-mode' will now inhibit
5927 re-highlighting of the article buffer.
5928
5929 *** New element in `gnus-boring-article-headers' -- `long-to'.
5930
5931 *** `M-i' symbolic prefix command. See the section "Symbolic
5932 Prefixes" in the Gnus manual for details.
5933
5934 *** `L' and `I' in the summary buffer now take the symbolic prefix
5935 `a' to add the score rule to the "all.SCORE" file.
5936
5937 *** `gnus-simplify-subject-functions' variable to allow greater
5938 control over simplification.
5939
5940 *** `A T' -- new command for fetching the current thread.
5941
5942 *** `/ T' -- new command for including the current thread in the
5943 limit.
5944
5945 *** `M-RET' is a new Message command for breaking cited text.
5946
5947 *** \\1-expressions are now valid in `nnmail-split-methods'.
5948
5949 *** The `custom-face-lookup' function has been removed.
5950 If you used this function in your initialization files, you must
5951 rewrite them to use `face-spec-set' instead.
5952
5953 *** Canceling now uses the current select method. Symbolic prefix
5954 `a' forces normal posting method.
5955
5956 *** New command to translate M******** sm*rtq**t*s into proper text
5957 -- `W d'.
5958
5959 *** For easier debugging of nntp, you can set `nntp-record-commands'
5960 to a non-nil value.
5961
5962 *** nntp now uses ~/.authinfo, a .netrc-like file, for controlling
5963 where and how to send AUTHINFO to NNTP servers.
5964
5965 *** A command for editing group parameters from the summary buffer
5966 has been added.
5967
5968 *** A history of where mails have been split is available.
5969
5970 *** A new article date command has been added -- `article-date-iso8601'.
5971
5972 *** Subjects can be simplified when threading by setting
5973 `gnus-score-thread-simplify'.
5974
5975 *** A new function for citing in Message has been added --
5976 `message-cite-original-without-signature'.
5977
5978 *** `article-strip-all-blank-lines' -- new article command.
5979
5980 *** A new Message command to kill to the end of the article has
5981 been added.
5982
5983 *** A minimum adaptive score can be specified by using the
5984 `gnus-adaptive-word-minimum' variable.
5985
5986 *** The "lapsed date" article header can be kept continually
5987 updated by the `gnus-start-date-timer' command.
5988
5989 *** Web listserv archives can be read with the nnlistserv backend.
5990
5991 *** Old dejanews archives can now be read by nnweb.
5992
5993 *** `gnus-posting-styles' has been re-activated.
5994
5995 ** Changes to TeX and LaTeX mode
5996
5997 *** The new variable `tex-start-options-string' can be used to give
5998 options for the TeX run. The default value causes TeX to run in
5999 nonstopmode. For an interactive TeX run set it to nil or "".
6000
6001 *** The command `tex-feed-input' sends input to the Tex Shell. In a
6002 TeX buffer it is bound to the keys C-RET, C-c RET, and C-c C-m (some
6003 of these keys may not work on all systems). For instance, if you run
6004 TeX interactively and if the TeX run stops because of an error, you
6005 can continue it without leaving the TeX buffer by typing C-RET.
6006
6007 *** The Tex Shell Buffer is now in `compilation-shell-minor-mode'.
6008 All error-parsing commands of the Compilation major mode are available
6009 but bound to keys that don't collide with the shell. Thus you can use
6010 the Tex Shell for command line executions like a usual shell.
6011
6012 *** The commands `tex-validate-region' and `tex-validate-buffer' check
6013 the matching of braces and $'s. The errors are listed in a *Occur*
6014 buffer and you can use C-c C-c or mouse-2 to go to a particular
6015 mismatch.
6016
6017 ** Changes to RefTeX mode
6018
6019 *** The table of contents buffer can now also display labels and
6020 file boundaries in addition to sections. Use `l', `i', and `c' keys.
6021
6022 *** Labels derived from context (the section heading) are now
6023 lowercase by default. To make the label legal in LaTeX, latin-1
6024 characters will lose their accent. All Mule characters will be
6025 removed from the label.
6026
6027 *** The automatic display of cross reference information can also use
6028 a window instead of the echo area. See variable `reftex-auto-view-crossref'.
6029
6030 *** kpsewhich can be used by RefTeX to find TeX and BibTeX files. See the
6031 customization group `reftex-finding-files'.
6032
6033 *** The option `reftex-bibfile-ignore-list' has been renamed to
6034 `reftex-bibfile-ignore-regexps' and indeed can be fed with regular
6035 expressions.
6036
6037 *** Multiple Selection buffers are now hidden buffers.
6038
6039 ** New/deleted modes and packages
6040
6041 *** The package snmp-mode.el provides major modes for editing SNMP and
6042 SNMPv2 MIBs. It has entries on `auto-mode-alist'.
6043
6044 *** The package sql.el provides a major mode, M-x sql-mode, for
6045 editing SQL files, and M-x sql-interactive-mode for interacting with
6046 SQL interpreters. It has an entry on `auto-mode-alist'.
6047
6048 *** M-x highlight-changes-mode provides a minor mode displaying buffer
6049 changes with a special face.
6050
6051 *** ispell4.el has been deleted. It got in the way of ispell.el and
6052 this was hard to fix reliably. It has long been obsolete -- use
6053 Ispell 3.1 and ispell.el.
6054 \f
6055 * MS-DOS changes in Emacs 20.4
6056
6057 ** Emacs compiled for MS-DOS now supports MULE features better.
6058 This includes support for display of all ISO 8859-N character sets,
6059 conversion to and from IBM codepage encoding of non-ASCII characters,
6060 and automatic setup of the MULE environment at startup. For details,
6061 check out the section `MS-DOS and MULE' in the manual.
6062
6063 The MS-DOS installation procedure automatically configures and builds
6064 Emacs with input method support if it finds an unpacked Leim
6065 distribution when the config.bat script is run.
6066
6067 ** Formerly, the value of lpr-command did not affect printing on
6068 MS-DOS unless print-region-function was set to nil, but now it
6069 controls whether an external program is invoked or output is written
6070 directly to a printer port. Similarly, in the previous version of
6071 Emacs, the value of ps-lpr-command did not affect PostScript printing
6072 on MS-DOS unless ps-printer-name was set to something other than a
6073 string (eg. t or `pipe'), but now it controls whether an external
6074 program is used. (These changes were made so that configuration of
6075 printing variables would be almost identical across all platforms.)
6076
6077 ** In the previous version of Emacs, PostScript and non-PostScript
6078 output was piped to external programs, but because most print programs
6079 available for MS-DOS and MS-Windows cannot read data from their standard
6080 input, on those systems the data to be output is now written to a
6081 temporary file whose name is passed as the last argument to the external
6082 program.
6083
6084 An exception is made for `print', a standard program on Windows NT,
6085 and `nprint', a standard program on Novell Netware. For both of these
6086 programs, the command line is constructed in the appropriate syntax
6087 automatically, using only the value of printer-name or ps-printer-name
6088 as appropriate--the value of the relevant `-switches' variable is
6089 ignored, as both programs have no useful switches.
6090
6091 ** The value of the variable dos-printer (cf. dos-ps-printer), if it has
6092 a value, overrides the value of printer-name (cf. ps-printer-name), on
6093 MS-DOS and MS-Windows only. This has been true since version 20.3, but
6094 was not documented clearly before.
6095
6096 ** All the Emacs games now work on MS-DOS terminals.
6097 This includes Tetris and Snake.
6098 \f
6099 * Lisp changes in Emacs 20.4
6100
6101 ** New functions line-beginning-position and line-end-position
6102 return the position of the beginning or end of the current line.
6103 They both accept an optional argument, which has the same
6104 meaning as the argument to beginning-of-line or end-of-line.
6105
6106 ** find-file and allied functions now have an optional argument
6107 WILDCARD. If this is non-nil, they do wildcard processing,
6108 and visit all files that match the wildcard pattern.
6109
6110 ** Changes in the file-attributes function.
6111
6112 *** The file size returned by file-attributes may be an integer or a float.
6113 It is an integer if the size fits in a Lisp integer, float otherwise.
6114
6115 *** The inode number returned by file-attributes may be an integer (if
6116 the number fits in a Lisp integer) or a cons cell containing two
6117 integers.
6118
6119 ** The new function directory-files-and-attributes returns a list of
6120 files in a directory and their attributes. It accepts the same
6121 arguments as directory-files and has similar semantics, except that
6122 file names and attributes are returned.
6123
6124 ** The new function file-attributes-lessp is a helper function for
6125 sorting the list generated by directory-files-and-attributes. It
6126 accepts two arguments, each a list of a file name and its attributes.
6127 It compares the file names of each according to string-lessp and
6128 returns the result.
6129
6130 ** The new function file-expand-wildcards expands a wildcard-pattern
6131 to produce a list of existing files that match the pattern.
6132
6133 ** New functions for base64 conversion:
6134
6135 The function base64-encode-region converts a part of the buffer
6136 into the base64 code used in MIME. base64-decode-region
6137 performs the opposite conversion. Line-breaking is supported
6138 optionally.
6139
6140 Functions base64-encode-string and base64-decode-string do a similar
6141 job on the text in a string. They return the value as a new string.
6142
6143 **
6144 The new function process-running-child-p
6145 will tell you if a subprocess has given control of its
6146 terminal to its own child process.
6147
6148 ** interrupt-process and such functions have a new feature:
6149 when the second argument is `lambda', they send a signal
6150 to the running child of the subshell, if any, but if the shell
6151 itself owns its terminal, no signal is sent.
6152
6153 ** There are new widget types `plist' and `alist' which can
6154 be used for customizing variables whose values are plists or alists.
6155
6156 ** easymenu.el now understands `:key-sequence' and `:style button'.
6157 :included is an alias for :visible.
6158
6159 easy-menu-add-item now understands the values returned by
6160 easy-menu-remove-item and easy-menu-item-present-p. This can be used
6161 to move or copy menu entries.
6162
6163 ** Multibyte editing changes
6164
6165 *** The definitions of sref and char-bytes are changed. Now, sref is
6166 an alias of aref and char-bytes always returns 1. This change is to
6167 make some Emacs Lisp code which works on 20.2 and earlier also
6168 work on the latest Emacs. Such code uses a combination of sref and
6169 char-bytes in a loop typically as below:
6170 (setq char (sref str idx)
6171 idx (+ idx (char-bytes idx)))
6172 The byte-compiler now warns that this is obsolete.
6173
6174 If you want to know how many bytes a specific multibyte character
6175 (say, CH) occupies in a multibyte buffer, use this code:
6176 (charset-bytes (char-charset ch))
6177
6178 *** In multibyte mode, when you narrow a buffer to some region, and the
6179 region is preceded or followed by non-ASCII codes, inserting or
6180 deleting at the head or the end of the region may signal this error:
6181
6182 Byte combining across boundary of accessible buffer text inhibited
6183
6184 This is to avoid some bytes being combined together into a character
6185 across the boundary.
6186
6187 *** The functions find-charset-region and find-charset-string include
6188 `unknown' in the returned list in the following cases:
6189 o The current buffer or the target string is unibyte and
6190 contains 8-bit characters.
6191 o The current buffer or the target string is multibyte and
6192 contains invalid characters.
6193
6194 *** The functions decode-coding-region and encode-coding-region remove
6195 text properties of the target region. Ideally, they should correctly
6196 preserve text properties, but for the moment, it's hard. Removing
6197 text properties is better than preserving them in a less-than-correct
6198 way.
6199
6200 *** prefer-coding-system sets EOL conversion of default coding systems.
6201 If the argument to prefer-coding-system specifies a certain type of
6202 end of line conversion, the default coding systems set by
6203 prefer-coding-system will specify that conversion type for end of line.
6204
6205 *** The new function thai-compose-string can be used to properly
6206 compose Thai characters in a string.
6207
6208 ** The primitive `define-prefix-command' now takes an optional third
6209 argument NAME, which should be a string. It supplies the menu name
6210 for the created keymap. Keymaps created in order to be displayed as
6211 menus should always use the third argument.
6212
6213 ** The meanings of optional second arguments for read-char,
6214 read-event, and read-char-exclusive are flipped. Now the second
6215 arguments are INHERIT-INPUT-METHOD. These functions use the current
6216 input method (if any) if and only if INHERIT-INPUT-METHOD is non-nil.
6217
6218 ** The new function clear-this-command-keys empties out the contents
6219 of the vector that (this-command-keys) returns. This is useful in
6220 programs that read passwords, to prevent the passwords from echoing
6221 inadvertently as part of the next command in certain cases.
6222
6223 ** The new macro `with-temp-message' displays a temporary message in
6224 the echo area, while executing some Lisp code. Like `progn', it
6225 returns the value of the last form, but it also restores the previous
6226 echo area contents.
6227
6228 (with-temp-message MESSAGE &rest BODY)
6229
6230 ** The function `require' now takes an optional third argument
6231 NOERROR. If it is non-nil, then there is no error if the
6232 requested feature cannot be loaded.
6233
6234 ** In the function modify-face, an argument of (nil) for the
6235 foreground color, background color or stipple pattern
6236 means to clear out that attribute.
6237
6238 ** The `outer-window-id' frame property of an X frame
6239 gives the window number of the outermost X window for the frame.
6240
6241 ** Temporary buffers made with with-output-to-temp-buffer are now
6242 read-only by default, and normally use the major mode Help mode
6243 unless you put them in some other non-Fundamental mode before the
6244 end of with-output-to-temp-buffer.
6245
6246 ** The new functions gap-position and gap-size return information on
6247 the gap of the current buffer.
6248
6249 ** The new functions position-bytes and byte-to-position provide a way
6250 to convert between character positions and byte positions in the
6251 current buffer.
6252
6253 ** vc.el defines two new macros, `edit-vc-file' and `with-vc-file', to
6254 facilitate working with version-controlled files from Lisp programs.
6255 These macros check out a given file automatically if needed, and check
6256 it back in after any modifications have been made.
6257 \f
6258 * Installation Changes in Emacs 20.3
6259
6260 ** The default value of load-path now includes most subdirectories of
6261 the site-specific directories /usr/local/share/emacs/site-lisp and
6262 /usr/local/share/emacs/VERSION/site-lisp, in addition to those
6263 directories themselves. Both immediate subdirectories and
6264 subdirectories multiple levels down are added to load-path.
6265
6266 Not all subdirectories are included, though. Subdirectories whose
6267 names do not start with a letter or digit are excluded.
6268 Subdirectories named RCS or CVS are excluded. Also, a subdirectory
6269 which contains a file named `.nosearch' is excluded. You can use
6270 these methods to prevent certain subdirectories from being searched.
6271
6272 Emacs finds these subdirectories and adds them to load-path when it
6273 starts up. While it would be cleaner to find the subdirectories each
6274 time Emacs loads a file, that would be much slower.
6275
6276 This feature is an incompatible change. If you have stored some Emacs
6277 Lisp files in a subdirectory of the site-lisp directory specifically
6278 to prevent them from being used, you will need to rename the
6279 subdirectory to start with a non-alphanumeric character, or create a
6280 `.nosearch' file in it, in order to continue to achieve the desired
6281 results.
6282
6283 ** Emacs no longer includes an old version of the C preprocessor from
6284 GCC. This was formerly used to help compile Emacs with C compilers
6285 that had limits on the significant length of an identifier, but in
6286 fact we stopped supporting such compilers some time ago.
6287 \f
6288 * Changes in Emacs 20.3
6289
6290 ** The new command C-x z (repeat) repeats the previous command
6291 including its argument. If you repeat the z afterward,
6292 it repeats the command additional times; thus, you can
6293 perform many repetitions with one keystroke per repetition.
6294
6295 ** Emacs now supports "selective undo" which undoes only within a
6296 specified region. To do this, set point and mark around the desired
6297 region and type C-u C-x u (or C-u C-_). You can then continue undoing
6298 further, within the same region, by repeating the ordinary undo
6299 command C-x u or C-_. This will keep undoing changes that were made
6300 within the region you originally specified, until either all of them
6301 are undone, or it encounters a change which crosses the edge of that
6302 region.
6303
6304 In Transient Mark mode, undoing when a region is active requests
6305 selective undo.
6306
6307 ** If you specify --unibyte when starting Emacs, then all buffers are
6308 unibyte, except when a Lisp program specifically creates a multibyte
6309 buffer. Setting the environment variable EMACS_UNIBYTE has the same
6310 effect. The --no-unibyte option overrides EMACS_UNIBYTE and directs
6311 Emacs to run normally in multibyte mode.
6312
6313 The option --unibyte does not affect the reading of Emacs Lisp files,
6314 though. If you want a Lisp file to be read in unibyte mode, use
6315 -*-unibyte: t;-*- on its first line. That will force Emacs to
6316 load that file in unibyte mode, regardless of how Emacs was started.
6317
6318 ** toggle-enable-multibyte-characters no longer has a key binding and
6319 no longer appears in the menu bar. We've realized that changing the
6320 enable-multibyte-characters variable in an existing buffer is
6321 something that most users not do.
6322
6323 ** You can specify a coding system to use for the next cut or paste
6324 operations through the window system with the command C-x RET X.
6325 The coding system can make a difference for communication with other
6326 applications.
6327
6328 C-x RET x specifies a coding system for all subsequent cutting and
6329 pasting operations.
6330
6331 ** You can specify the printer to use for commands that do printing by
6332 setting the variable `printer-name'. Just what a printer name looks
6333 like depends on your operating system. You can specify a different
6334 printer for the Postscript printing commands by setting
6335 `ps-printer-name'.
6336
6337 ** Emacs now supports on-the-fly spell checking by the means of a
6338 minor mode. It is called M-x flyspell-mode. You don't have to remember
6339 any other special commands to use it, and you will hardly notice it
6340 except when you make a spelling error. Flyspell works by highlighting
6341 incorrect words as soon as they are completed or as soon as the cursor
6342 hits a new word.
6343
6344 Flyspell mode works with whichever dictionary you have selected for
6345 Ispell in Emacs. In TeX mode, it understands TeX syntax so as not
6346 to be confused by TeX commands.
6347
6348 You can correct a misspelled word by editing it into something
6349 correct. You can also correct it, or accept it as correct, by
6350 clicking on the word with Mouse-2; that gives you a pop-up menu
6351 of various alternative replacements and actions.
6352
6353 Flyspell mode also proposes "automatic" corrections. M-TAB replaces
6354 the current misspelled word with a possible correction. If several
6355 corrections are made possible, M-TAB cycles through them in
6356 alphabetical order, or in order of decreasing likelihood if
6357 flyspell-sort-corrections is nil.
6358
6359 Flyspell mode also flags an error when a word is repeated, if
6360 flyspell-mark-duplications-flag is non-nil.
6361
6362 ** Changes in input method usage.
6363
6364 Now you can use arrow keys (right, left, down, up) for selecting among
6365 the alternatives just the same way as you do by C-f, C-b, C-n, and C-p
6366 respectively.
6367
6368 You can use the ENTER key to accept the current conversion.
6369
6370 If you type TAB to display a list of alternatives, you can select one
6371 of the alternatives with Mouse-2.
6372
6373 The meaning of the variable `input-method-verbose-flag' is changed so
6374 that you can set it to t, nil, `default', or `complex-only'.
6375
6376 If the value is nil, extra guidance is never given.
6377
6378 If the value is t, extra guidance is always given.
6379
6380 If the value is `complex-only', extra guidance is always given only
6381 when you are using complex input methods such as chinese-py.
6382
6383 If the value is `default' (this is the default), extra guidance is
6384 given in the following case:
6385 o When you are using a complex input method.
6386 o When you are using a simple input method but not in the minibuffer.
6387
6388 If you are using Emacs through a very slow line, setting
6389 input-method-verbose-flag to nil or to complex-only is a good choice,
6390 and if you are using an input method you are not familiar with,
6391 setting it to t is helpful.
6392
6393 The old command select-input-method is now called set-input-method.
6394
6395 In the language environment "Korean", you can use the following
6396 keys:
6397 Shift-SPC toggle-korean-input-method
6398 C-F9 quail-hangul-switch-symbol-ksc
6399 F9 quail-hangul-switch-hanja
6400 These key bindings are canceled when you switch to another language
6401 environment.
6402
6403 ** The minibuffer history of file names now records the specified file
6404 names, not the entire minibuffer input. For example, if the
6405 minibuffer starts out with /usr/foo/, you might type in /etc/passwd to
6406 get
6407
6408 /usr/foo//etc/passwd
6409
6410 which stands for the file /etc/passwd.
6411
6412 Formerly, this used to put /usr/foo//etc/passwd in the history list.
6413 Now this puts just /etc/passwd in the history list.
6414
6415 ** If you are root, Emacs sets backup-by-copying-when-mismatch to t
6416 at startup, so that saving a file will be sure to preserve
6417 its owner and group.
6418
6419 ** find-func.el can now also find the place of definition of Emacs
6420 Lisp variables in user-loaded libraries.
6421
6422 ** C-x r t (string-rectangle) now deletes the existing rectangle
6423 contents before inserting the specified string on each line.
6424
6425 ** There is a new command delete-whitespace-rectangle
6426 which deletes whitespace starting from a particular column
6427 in all the lines on a rectangle. The column is specified
6428 by the left edge of the rectangle.
6429
6430 ** You can now store a number into a register with C-u NUMBER C-x r n REG,
6431 increment it by INC with C-u INC C-x r + REG (to increment by one, omit
6432 C-u INC), and insert it in the buffer with C-x r g REG. This is useful
6433 for writing keyboard macros.
6434
6435 ** The new command M-x speedbar displays a frame in which directories,
6436 files, and tags can be displayed, manipulated, and jumped to. The
6437 frame defaults to 20 characters in width, and is the same height as
6438 the frame that it was started from. Some major modes define
6439 additional commands for the speedbar, including Rmail, GUD/GDB, and
6440 info.
6441
6442 ** query-replace-regexp is now bound to C-M-%.
6443
6444 ** In Transient Mark mode, when the region is active, M-x
6445 query-replace and the other replace commands now operate on the region
6446 contents only.
6447
6448 ** M-x write-region, when used interactively, now asks for
6449 confirmation before overwriting an existing file. When you call
6450 the function from a Lisp program, a new optional argument CONFIRM
6451 says whether to ask for confirmation in this case.
6452
6453 ** If you use find-file-literally and the file is already visited
6454 non-literally, the command asks you whether to revisit the file
6455 literally. If you say no, it signals an error.
6456
6457 ** Major modes defined with the "derived mode" feature
6458 now use the proper name for the mode hook: WHATEVER-mode-hook.
6459 Formerly they used the name WHATEVER-mode-hooks, but that is
6460 inconsistent with Emacs conventions.
6461
6462 ** shell-command-on-region (and shell-command) reports success or
6463 failure if the command produces no output.
6464
6465 ** Set focus-follows-mouse to nil if your window system or window
6466 manager does not transfer focus to another window when you just move
6467 the mouse.
6468
6469 ** mouse-menu-buffer-maxlen has been renamed to
6470 mouse-buffer-menu-maxlen to be consistent with the other related
6471 function and variable names.
6472
6473 ** The new variable auto-coding-alist specifies coding systems for
6474 reading specific files. This has higher priority than
6475 file-coding-system-alist.
6476
6477 ** If you set the variable unibyte-display-via-language-environment to
6478 t, then Emacs displays non-ASCII characters are displayed by
6479 converting them to the equivalent multibyte characters according to
6480 the current language environment. As a result, they are displayed
6481 according to the current fontset.
6482
6483 ** C-q's handling of codes in the range 0200 through 0377 is changed.
6484
6485 The codes in the range 0200 through 0237 are inserted as one byte of
6486 that code regardless of the values of nonascii-translation-table and
6487 nonascii-insert-offset.
6488
6489 For the codes in the range 0240 through 0377, if
6490 enable-multibyte-characters is non-nil and nonascii-translation-table
6491 nor nonascii-insert-offset can't convert them to valid multibyte
6492 characters, they are converted to Latin-1 characters.
6493
6494 ** If you try to find a file that is not read-accessible, you now get
6495 an error, rather than an empty buffer and a warning.
6496
6497 ** In the minibuffer history commands M-r and M-s, an upper case
6498 letter in the regular expression forces case-sensitive search.
6499
6500 ** In the *Help* buffer, cross-references to commands and variables
6501 are inferred and hyperlinked. Use C-h m in Help mode for the relevant
6502 command keys.
6503
6504 ** M-x apropos-command, with a prefix argument, no longer looks for
6505 user option variables--instead it looks for noninteractive functions.
6506
6507 Meanwhile, the command apropos-variable normally searches for
6508 user option variables; with a prefix argument, it looks at
6509 all variables that have documentation.
6510
6511 ** When you type a long line in the minibuffer, and the minibuffer
6512 shows just one line, automatically scrolling works in a special way
6513 that shows you overlap with the previous line of text. The variable
6514 minibuffer-scroll-overlap controls how many characters of overlap
6515 it should show; the default is 20.
6516
6517 Meanwhile, Resize Minibuffer mode is still available; in that mode,
6518 the minibuffer grows taller (up to a point) as needed to show the whole
6519 of your input.
6520
6521 ** The new command M-x customize-changed-options lets you customize
6522 all the options whose meanings or default values have changed in
6523 recent Emacs versions. You specify a previous Emacs version number as
6524 argument, and the command creates a customization buffer showing all
6525 the customizable options which were changed since that version.
6526 Newly added options are included as well.
6527
6528 If you don't specify a particular version number argument,
6529 then the customization buffer shows all the customizable options
6530 for which Emacs versions of changes are recorded.
6531
6532 This function is also bound to the Changed Options entry in the
6533 Customize menu.
6534
6535 ** When you run M-x grep with a prefix argument, it figures out
6536 the tag around point and puts that into the default grep command.
6537
6538 ** The new command M-* (pop-tag-mark) pops back through a history of
6539 buffer positions from which M-. or other tag-finding commands were
6540 invoked.
6541
6542 ** The new variable comment-padding specifies the number of spaces
6543 that `comment-region' will insert before the actual text of the comment.
6544 The default is 1.
6545
6546 ** In Fortran mode the characters `.', `_' and `$' now have symbol
6547 syntax, not word syntax. Fortran mode now supports `imenu' and has
6548 new commands fortran-join-line (M-^) and fortran-narrow-to-subprogram
6549 (C-x n d). M-q can be used to fill a statement or comment block
6550 sensibly.
6551
6552 ** GUD now supports jdb, the Java debugger, and pdb, the Python debugger.
6553
6554 ** If you set the variable add-log-keep-changes-together to a non-nil
6555 value, the command `C-x 4 a' will automatically notice when you make
6556 two entries in one day for one file, and combine them.
6557
6558 ** You can use the command M-x diary-mail-entries to mail yourself a
6559 reminder about upcoming diary entries. See the documentation string
6560 for a sample shell script for calling this function automatically
6561 every night.
6562
6563 ** Desktop changes
6564
6565 *** All you need to do to enable use of the Desktop package, is to set
6566 the variable desktop-enable to t with Custom.
6567
6568 *** Minor modes are now restored. Which minor modes are restored
6569 and how modes are restored is controlled by `desktop-minor-mode-table'.
6570
6571 ** There is no need to do anything special, now, to enable Gnus to
6572 read and post multi-lingual articles.
6573
6574 ** Outline mode has now support for showing hidden outlines when
6575 doing an isearch. In order for this to happen search-invisible should
6576 be set to open (the default). If an isearch match is inside a hidden
6577 outline the outline is made visible. If you continue pressing C-s and
6578 the match moves outside the formerly invisible outline, the outline is
6579 made invisible again.
6580
6581 ** Mail reading and sending changes
6582
6583 *** The Rmail e command now switches to displaying the whole header of
6584 the message before it lets you edit the message. This is so that any
6585 changes you make in the header will not be lost if you subsequently
6586 toggle.
6587
6588 *** The w command in Rmail, which writes the message body into a file,
6589 now works in the summary buffer as well. (The command to delete the
6590 summary buffer is now Q.) The default file name for the w command, if
6591 the message has no subject, is stored in the variable
6592 rmail-default-body-file.
6593
6594 *** Most of the commands and modes that operate on mail and netnews no
6595 longer depend on the value of mail-header-separator. Instead, they
6596 handle whatever separator the buffer happens to use.
6597
6598 *** If you set mail-signature to a value which is not t, nil, or a string,
6599 it should be an expression. When you send a message, this expression
6600 is evaluated to insert the signature.
6601
6602 *** The new Lisp library feedmail.el (version 8) enhances processing of
6603 outbound email messages. It works in coordination with other email
6604 handling packages (e.g., rmail, VM, gnus) and is responsible for
6605 putting final touches on messages and actually submitting them for
6606 transmission. Users of the emacs program "fakemail" might be
6607 especially interested in trying feedmail.
6608
6609 feedmail is not enabled by default. See comments at the top of
6610 feedmail.el for set-up instructions. Among the bigger features
6611 provided by feedmail are:
6612
6613 **** you can park outgoing messages into a disk-based queue and
6614 stimulate sending some or all of them later (handy for laptop users);
6615 there is also a queue for draft messages
6616
6617 **** you can get one last look at the prepped outbound message and
6618 be prompted for confirmation
6619
6620 **** does smart filling of address headers
6621
6622 **** can generate a MESSAGE-ID: line and a DATE: line; the date can be
6623 the time the message was written or the time it is being sent; this
6624 can make FCC copies more closely resemble copies that recipients get
6625
6626 **** you can specify an arbitrary function for actually transmitting
6627 the message; included in feedmail are interfaces for /bin/[r]mail,
6628 /usr/lib/sendmail, and elisp smtpmail; it's easy to write a new
6629 function for something else (10-20 lines of elisp)
6630
6631 ** Dired changes
6632
6633 *** The Dired function dired-do-toggle, which toggles marked and unmarked
6634 files, is now bound to "t" instead of "T".
6635
6636 *** dired-at-point has been added to ffap.el. It allows one to easily
6637 run Dired on the directory name at point.
6638
6639 *** Dired has a new command: %g. It searches the contents of
6640 files in the directory and marks each file that contains a match
6641 for a specified regexp.
6642
6643 ** VC Changes
6644
6645 *** New option vc-ignore-vc-files lets you turn off version control
6646 conveniently.
6647
6648 *** VC Dired has been completely rewritten. It is now much
6649 faster, especially for CVS, and works very similar to ordinary
6650 Dired.
6651
6652 VC Dired is invoked by typing C-x v d and entering the name of the
6653 directory to display. By default, VC Dired gives you a recursive
6654 listing of all files at or below the given directory which are
6655 currently locked (for CVS, all files not up-to-date are shown).
6656
6657 You can change the listing format by setting vc-dired-recurse to nil,
6658 then it shows only the given directory, and you may also set
6659 vc-dired-terse-display to nil, then it shows all files under version
6660 control plus the names of any subdirectories, so that you can type `i'
6661 on such lines to insert them manually, as in ordinary Dired.
6662
6663 All Dired commands operate normally in VC Dired, except for `v', which
6664 is redefined as the version control prefix. That means you may type
6665 `v l', `v =' etc. to invoke `vc-print-log', `vc-diff' and the like on
6666 the file named in the current Dired buffer line. `v v' invokes
6667 `vc-next-action' on this file, or on all files currently marked.
6668
6669 The new command `v t' (vc-dired-toggle-terse-mode) allows you to
6670 toggle between terse display (only locked files) and full display (all
6671 VC files plus subdirectories). There is also a special command,
6672 `* l', to mark all files currently locked.
6673
6674 Giving a prefix argument to C-x v d now does the same thing as in
6675 ordinary Dired: it allows you to supply additional options for the ls
6676 command in the minibuffer, to fine-tune VC Dired's output.
6677
6678 *** Under CVS, if you merge changes from the repository into a working
6679 file, and CVS detects conflicts, VC now offers to start an ediff
6680 session to resolve them.
6681
6682 Alternatively, you can use the new command `vc-resolve-conflicts' to
6683 resolve conflicts in a file at any time. It works in any buffer that
6684 contains conflict markers as generated by rcsmerge (which is what CVS
6685 uses as well).
6686
6687 *** You can now transfer changes between branches, using the new
6688 command vc-merge (C-x v m). It is implemented for RCS and CVS. When
6689 you invoke it in a buffer under version-control, you can specify
6690 either an entire branch or a pair of versions, and the changes on that
6691 branch or between the two versions are merged into the working file.
6692 If this results in any conflicts, they may be resolved interactively,
6693 using ediff.
6694
6695 ** Changes in Font Lock
6696
6697 *** The face and variable previously known as font-lock-reference-face
6698 are now called font-lock-constant-face to better reflect their typical
6699 use for highlighting constants and labels. (Its face properties are
6700 unchanged.) The variable font-lock-reference-face remains for now for
6701 compatibility reasons, but its value is font-lock-constant-face.
6702
6703 ** Frame name display changes
6704
6705 *** The command set-frame-name lets you set the name of the current
6706 frame. You can use the new command select-frame-by-name to select and
6707 raise a frame; this is mostly useful on character-only terminals, or
6708 when many frames are invisible or iconified.
6709
6710 *** On character-only terminal (not a window system), changing the
6711 frame name is now reflected on the mode line and in the Buffers/Frames
6712 menu.
6713
6714 ** Comint (subshell) changes
6715
6716 *** In Comint modes, the commands to kill, stop or interrupt a
6717 subjob now also kill pending input. This is for compatibility
6718 with ordinary shells, where the signal characters do this.
6719
6720 *** There are new commands in Comint mode.
6721
6722 C-c C-x fetches the "next" line from the input history;
6723 that is, the line after the last line you got.
6724 You can use this command to fetch successive lines, one by one.
6725
6726 C-c SPC accumulates lines of input. More precisely, it arranges to
6727 send the current line together with the following line, when you send
6728 the following line.
6729
6730 C-c C-a if repeated twice consecutively now moves to the process mark,
6731 which separates the pending input from the subprocess output and the
6732 previously sent input.
6733
6734 C-c M-r now runs comint-previous-matching-input-from-input;
6735 it searches for a previous command, using the current pending input
6736 as the search string.
6737
6738 *** New option compilation-scroll-output can be set to scroll
6739 automatically in compilation-mode windows.
6740
6741 ** C mode changes
6742
6743 *** Multiline macros are now handled, both as they affect indentation,
6744 and as recognized syntax. New syntactic symbol cpp-macro-cont is
6745 assigned to second and subsequent lines of a multiline macro
6746 definition.
6747
6748 *** A new style "user" which captures all non-hook-ified
6749 (i.e. top-level) .emacs file variable settings and customizations.
6750 Style "cc-mode" is an alias for "user" and is deprecated. "gnu"
6751 style is still the default however.
6752
6753 *** "java" style now conforms to Sun's JDK coding style.
6754
6755 *** There are new commands c-beginning-of-defun, c-end-of-defun which
6756 are alternatives which you could bind to C-M-a and C-M-e if you prefer
6757 them. They do not have key bindings by default.
6758
6759 *** New and improved implementations of M-a (c-beginning-of-statement)
6760 and M-e (c-end-of-statement).
6761
6762 *** C++ namespace blocks are supported, with new syntactic symbols
6763 namespace-open, namespace-close, and innamespace.
6764
6765 *** File local variable settings of c-file-style and c-file-offsets
6766 makes the style variables local to that buffer only.
6767
6768 *** New indentation functions c-lineup-close-paren,
6769 c-indent-one-line-block, c-lineup-dont-change.
6770
6771 *** Improvements (hopefully!) to the way CC Mode is loaded. You
6772 should now be able to do a (require 'cc-mode) to get the entire
6773 package loaded properly for customization in your .emacs file. A new
6774 variable c-initialize-on-load controls this and is t by default.
6775
6776 ** Changes to hippie-expand.
6777
6778 *** New customization variable `hippie-expand-dabbrev-skip-space'. If
6779 non-nil, trailing spaces may be included in the abbreviation to search for,
6780 which then gives the same behavior as the original `dabbrev-expand'.
6781
6782 *** New customization variable `hippie-expand-dabbrev-as-symbol'. If
6783 non-nil, characters of syntax '_' is considered part of the word when
6784 expanding dynamically.
6785
6786 *** New customization variable `hippie-expand-no-restriction'. If
6787 non-nil, narrowed buffers are widened before they are searched.
6788
6789 *** New customization variable `hippie-expand-only-buffers'. If
6790 non-empty, buffers searched are restricted to the types specified in
6791 this list. Useful for example when constructing new special-purpose
6792 expansion functions with `make-hippie-expand-function'.
6793
6794 *** Text properties of the expansion are no longer copied.
6795
6796 ** Changes in BibTeX mode.
6797
6798 *** Any titleword matching a regexp in the new variable
6799 bibtex-autokey-titleword-ignore (case sensitive) is ignored during
6800 automatic key generation. This replaces variable
6801 bibtex-autokey-titleword-first-ignore, which only checked for matches
6802 against the first word in the title.
6803
6804 *** Autokey generation now uses all words from the title, not just
6805 capitalized words. To avoid conflicts with existing customizations,
6806 bibtex-autokey-titleword-ignore is set up such that words starting with
6807 lowerkey characters will still be ignored. Thus, if you want to use
6808 lowercase words from the title, you will have to overwrite the
6809 bibtex-autokey-titleword-ignore standard setting.
6810
6811 *** Case conversion of names and title words for automatic key
6812 generation is more flexible. Variable bibtex-autokey-preserve-case is
6813 replaced by bibtex-autokey-titleword-case-convert and
6814 bibtex-autokey-name-case-convert.
6815
6816 ** Changes in vcursor.el.
6817
6818 *** Support for character terminals is available: there is a new keymap
6819 and the vcursor will appear as an arrow between buffer text. A
6820 variable `vcursor-interpret-input' allows input from the vcursor to be
6821 entered exactly as if typed. Numerous functions, including
6822 `vcursor-compare-windows', have been rewritten to improve consistency
6823 in the selection of windows and corresponding keymaps.
6824
6825 *** vcursor options can now be altered with M-x customize under the
6826 Editing group once the package is loaded.
6827
6828 *** Loading vcursor now does not define keys by default, as this is
6829 generally a bad side effect. Use M-x customize to set
6830 vcursor-key-bindings to t to restore the old behavior.
6831
6832 *** vcursor-auto-disable can be `copy', which turns off copying from the
6833 vcursor, but doesn't disable it, after any non-vcursor command.
6834
6835 ** Ispell changes.
6836
6837 *** You can now spell check comments and strings in the current
6838 buffer with M-x ispell-comments-and-strings. Comments and strings
6839 are identified by syntax tables in effect.
6840
6841 *** Generic region skipping implemented.
6842 A single buffer can be broken into a number of regions where text will
6843 and will not be checked. The definitions of the regions can be user
6844 defined. New applications and improvements made available by this
6845 include:
6846
6847 o URLs are automatically skipped
6848 o EMail message checking is vastly improved.
6849
6850 *** Ispell can highlight the erroneous word even on non-window terminals.
6851
6852 ** Changes to RefTeX mode
6853
6854 RefTeX has been updated in order to make it more usable with very
6855 large projects (like a several volume math book). The parser has been
6856 re-written from scratch. To get maximum speed from RefTeX, check the
6857 section `Optimizations' in the manual.
6858
6859 *** New recursive parser.
6860
6861 The old version of RefTeX created a single large buffer containing the
6862 entire multifile document in order to parse the document. The new
6863 recursive parser scans the individual files.
6864
6865 *** Parsing only part of a document.
6866
6867 Reparsing of changed document parts can now be made faster by enabling
6868 partial scans. To use this feature, read the documentation string of
6869 the variable `reftex-enable-partial-scans' and set the variable to t.
6870
6871 (setq reftex-enable-partial-scans t)
6872
6873 *** Storing parsing information in a file.
6874
6875 This can improve startup times considerably. To turn it on, use
6876
6877 (setq reftex-save-parse-info t)
6878
6879 *** Using multiple selection buffers
6880
6881 If the creation of label selection buffers is too slow (this happens
6882 for large documents), you can reuse these buffers by setting
6883
6884 (setq reftex-use-multiple-selection-buffers t)
6885
6886 *** References to external documents.
6887
6888 The LaTeX package `xr' allows to cross-reference labels in external
6889 documents. RefTeX can provide information about the external
6890 documents as well. To use this feature, set up the \externaldocument
6891 macros required by the `xr' package and rescan the document with
6892 RefTeX. The external labels can then be accessed with the `x' key in
6893 the selection buffer provided by `reftex-reference' (bound to `C-c )').
6894 The `x' key also works in the table of contents buffer.
6895
6896 *** Many more labeled LaTeX environments are recognized by default.
6897
6898 The built-in command list now covers all the standard LaTeX commands,
6899 and all of the major packages included in the LaTeX distribution.
6900
6901 Also, RefTeX now understands the \appendix macro and changes
6902 the enumeration of sections in the *toc* buffer accordingly.
6903
6904 *** Mouse support for selection and *toc* buffers
6905
6906 The mouse can now be used to select items in the selection and *toc*
6907 buffers. See also the new option `reftex-highlight-selection'.
6908
6909 *** New keymaps for selection and table of contents modes.
6910
6911 The selection processes for labels and citation keys, and the table of
6912 contents buffer now have their own keymaps: `reftex-select-label-map',
6913 `reftex-select-bib-map', `reftex-toc-map'. The selection processes
6914 have a number of new keys predefined. In particular, TAB lets you
6915 enter a label with completion. Check the on-the-fly help (press `?'
6916 at the selection prompt) or read the Info documentation to find out
6917 more.
6918
6919 *** Support for the varioref package
6920
6921 The `v' key in the label selection buffer toggles \ref versus \vref.
6922
6923 *** New hooks
6924
6925 Three new hooks can be used to redefine the way labels, references,
6926 and citations are created. These hooks are
6927 `reftex-format-label-function', `reftex-format-ref-function',
6928 `reftex-format-cite-function'.
6929
6930 *** Citations outside LaTeX
6931
6932 The command `reftex-citation' may also be used outside LaTeX (e.g. in
6933 a mail buffer). See the Info documentation for details.
6934
6935 *** Short context is no longer fontified.
6936
6937 The short context in the label menu no longer copies the
6938 fontification from the text in the buffer. If you prefer it to be
6939 fontified, use
6940
6941 (setq reftex-refontify-context t)
6942
6943 ** file-cache-minibuffer-complete now accepts a prefix argument.
6944 With a prefix argument, it does not try to do completion of
6945 the file name within its directory; it only checks for other
6946 directories that contain the same file name.
6947
6948 Thus, given the file name Makefile, and assuming that a file
6949 Makefile.in exists in the same directory, ordinary
6950 file-cache-minibuffer-complete will try to complete Makefile to
6951 Makefile.in and will therefore never look for other directories that
6952 have Makefile. A prefix argument tells it not to look for longer
6953 names such as Makefile.in, so that instead it will look for other
6954 directories--just as if the name were already complete in its present
6955 directory.
6956
6957 ** New modes and packages
6958
6959 *** There is a new alternative major mode for Perl, Cperl mode.
6960 It has many more features than Perl mode, and some people prefer
6961 it, but some do not.
6962
6963 *** There is a new major mode, M-x vhdl-mode, for editing files of VHDL
6964 code.
6965
6966 *** M-x which-function-mode enables a minor mode that displays the
6967 current function name continuously in the mode line, as you move
6968 around in a buffer.
6969
6970 Which Function mode is effective in major modes which support Imenu.
6971
6972 *** Gametree is a major mode for editing game analysis trees. The author
6973 uses it for keeping notes about his postal Chess games, but it should
6974 be helpful for other two-player games as well, as long as they have an
6975 established system of notation similar to Chess.
6976
6977 *** The new minor mode checkdoc-minor-mode provides Emacs Lisp
6978 documentation string checking for style and spelling. The style
6979 guidelines are found in the Emacs Lisp programming manual.
6980
6981 *** The net-utils package makes some common networking features
6982 available in Emacs. Some of these functions are wrappers around
6983 system utilities (ping, nslookup, etc); others are implementations of
6984 simple protocols (finger, whois) in Emacs Lisp. There are also
6985 functions to make simple connections to TCP/IP ports for debugging and
6986 the like.
6987
6988 *** highlight-changes-mode is a minor mode that uses colors to
6989 identify recently changed parts of the buffer text.
6990
6991 *** The new package `midnight' lets you specify things to be done
6992 within Emacs at midnight--by default, kill buffers that you have not
6993 used in a considerable time. To use this feature, customize
6994 the user option `midnight-mode' to t.
6995
6996 *** The file generic-x.el defines a number of simple major modes.
6997
6998 apache-generic-mode: For Apache and NCSA httpd configuration files
6999 samba-generic-mode: Samba configuration files
7000 fvwm-generic-mode: For fvwm initialization files
7001 x-resource-generic-mode: For X resource files
7002 hosts-generic-mode: For hosts files (.rhosts, /etc/hosts, etc)
7003 mailagent-rules-generic-mode: For mailagent .rules files
7004 javascript-generic-mode: For JavaScript files
7005 vrml-generic-mode: For VRML files
7006 java-manifest-generic-mode: For Java MANIFEST files
7007 java-properties-generic-mode: For Java property files
7008 mailrc-generic-mode: For .mailrc files
7009
7010 Platform-specific modes:
7011
7012 prototype-generic-mode: For Solaris/Sys V prototype files
7013 pkginfo-generic-mode: For Solaris/Sys V pkginfo files
7014 alias-generic-mode: For C shell alias files
7015 inf-generic-mode: For MS-Windows INF files
7016 ini-generic-mode: For MS-Windows INI files
7017 reg-generic-mode: For MS-Windows Registry files
7018 bat-generic-mode: For MS-Windows BAT scripts
7019 rc-generic-mode: For MS-Windows Resource files
7020 rul-generic-mode: For InstallShield scripts
7021 \f
7022 * Lisp changes in Emacs 20.3 since the Emacs Lisp Manual was published
7023
7024 ** If you want a Lisp file to be read in unibyte mode,
7025 use -*-unibyte: t;-*- on its first line.
7026 That will force Emacs to read that file in unibyte mode.
7027 Otherwise, the file will be loaded and byte-compiled in multibyte mode.
7028
7029 Thus, each lisp file is read in a consistent way regardless of whether
7030 you started Emacs with --unibyte, so that a Lisp program gives
7031 consistent results regardless of how Emacs was started.
7032
7033 ** The new function assoc-default is useful for searching an alist,
7034 and using a default value if the key is not found there. You can
7035 specify a comparison predicate, so this function is useful for
7036 searching comparing a string against an alist of regular expressions.
7037
7038 ** The functions unibyte-char-to-multibyte and
7039 multibyte-char-to-unibyte convert between unibyte and multibyte
7040 character codes, in a way that is appropriate for the current language
7041 environment.
7042
7043 ** The functions read-event, read-char and read-char-exclusive now
7044 take two optional arguments. PROMPT, if non-nil, specifies a prompt
7045 string. SUPPRESS-INPUT-METHOD, if non-nil, says to disable the
7046 current input method for reading this one event.
7047
7048 ** Two new variables print-escape-nonascii and print-escape-multibyte
7049 now control whether to output certain characters as
7050 backslash-sequences. print-escape-nonascii applies to single-byte
7051 non-ASCII characters; print-escape-multibyte applies to multibyte
7052 characters. Both of these variables are used only when printing
7053 in readable fashion (prin1 uses them, princ does not).
7054 \f
7055 * Lisp changes in Emacs 20.3 before the Emacs Lisp Manual was published
7056
7057 ** Compiled Emacs Lisp files made with the modified "MBSK" version
7058 of Emacs 20.2 do not work in Emacs 20.3.
7059
7060 ** Buffer positions are now measured in characters, as they were
7061 in Emacs 19 and before. This means that (forward-char 1)
7062 always increases point by 1.
7063
7064 The function chars-in-region now just subtracts its arguments. It is
7065 considered obsolete. The function char-boundary-p has been deleted.
7066
7067 See below for additional changes relating to multibyte characters.
7068
7069 ** defcustom, defface and defgroup now accept the keyword `:version'.
7070 Use this to specify in which version of Emacs a certain variable's
7071 default value changed. For example,
7072
7073 (defcustom foo-max 34 "*Maximum number of foo's allowed."
7074 :type 'integer
7075 :group 'foo
7076 :version "20.3")
7077
7078 (defgroup foo-group nil "The foo group."
7079 :version "20.3")
7080
7081 If an entire new group is added or the variables in it have the
7082 default values changed, then just add a `:version' to that group. It
7083 is recommended that new packages added to the distribution contain a
7084 `:version' in the top level group.
7085
7086 This information is used to control the customize-changed-options command.
7087
7088 ** It is now an error to change the value of a symbol whose name
7089 starts with a colon--if it is interned in the standard obarray.
7090
7091 However, setting such a symbol to its proper value, which is that
7092 symbol itself, is not an error. This is for the sake of programs that
7093 support previous Emacs versions by explicitly setting these variables
7094 to themselves.
7095
7096 If you set the variable keyword-symbols-constant-flag to nil,
7097 this error is suppressed, and you can set these symbols to any
7098 values whatever.
7099
7100 ** There is a new debugger command, R.
7101 It evaluates an expression like e, but saves the result
7102 in the buffer *Debugger-record*.
7103
7104 ** Frame-local variables.
7105
7106 You can now make a variable local to various frames. To do this, call
7107 the function make-variable-frame-local; this enables frames to have
7108 local bindings for that variable.
7109
7110 These frame-local bindings are actually frame parameters: you create a
7111 frame-local binding in a specific frame by calling
7112 modify-frame-parameters and specifying the variable name as the
7113 parameter name.
7114
7115 Buffer-local bindings take precedence over frame-local bindings.
7116 Thus, if the current buffer has a buffer-local binding, that binding is
7117 active; otherwise, if the selected frame has a frame-local binding,
7118 that binding is active; otherwise, the default binding is active.
7119
7120 It would not be hard to implement window-local bindings, but it is not
7121 clear that this would be very useful; windows tend to come and go in a
7122 very transitory fashion, so that trying to produce any specific effect
7123 through a window-local binding would not be very robust.
7124
7125 ** `sregexq' and `sregex' are two new functions for constructing
7126 "symbolic regular expressions." These are Lisp expressions that, when
7127 evaluated, yield conventional string-based regexps. The symbolic form
7128 makes it easier to construct, read, and maintain complex patterns.
7129 See the documentation in sregex.el.
7130
7131 ** parse-partial-sexp's return value has an additional element which
7132 is used to pass information along if you pass it to another call to
7133 parse-partial-sexp, starting its scan where the first call ended.
7134 The contents of this field are not yet finalized.
7135
7136 ** eval-region now accepts a fourth optional argument READ-FUNCTION.
7137 If it is non-nil, that function is used instead of `read'.
7138
7139 ** unload-feature by default removes the feature's functions from
7140 known hooks to avoid trouble, but a package providing FEATURE can
7141 define a hook FEATURE-unload-hook to be run by unload-feature instead.
7142
7143 ** read-from-minibuffer no longer returns the argument DEFAULT-VALUE
7144 when the user enters empty input. It now returns the null string, as
7145 it did in Emacs 19. The default value is made available in the
7146 history via M-n, but it is not applied here as a default.
7147
7148 The other, more specialized minibuffer-reading functions continue to
7149 return the default value (not the null string) when the user enters
7150 empty input.
7151
7152 ** The new variable read-buffer-function controls which routine to use
7153 for selecting buffers. For example, if you set this variable to
7154 `iswitchb-read-buffer', iswitchb will be used to read buffer names.
7155 Other functions can also be used if they accept the same arguments as
7156 `read-buffer' and return the selected buffer name as a string.
7157
7158 ** The new function read-passwd reads a password from the terminal,
7159 echoing a period for each character typed. It takes three arguments:
7160 a prompt string, a flag which says "read it twice to make sure", and a
7161 default password to use if the user enters nothing.
7162
7163 ** The variable fill-nobreak-predicate gives major modes a way to
7164 specify not to break a line at certain places. Its value is a
7165 function which is called with no arguments, with point located at the
7166 place where a break is being considered. If the function returns
7167 non-nil, then the line won't be broken there.
7168
7169 ** window-end now takes an optional second argument, UPDATE.
7170 If this is non-nil, then the function always returns an accurate
7171 up-to-date value for the buffer position corresponding to the
7172 end of the window, even if this requires computation.
7173
7174 ** other-buffer now takes an optional argument FRAME
7175 which specifies which frame's buffer list to use.
7176 If it is nil, that means use the selected frame's buffer list.
7177
7178 ** The new variable buffer-display-time, always local in every buffer,
7179 holds the value of (current-time) as of the last time that a window
7180 was directed to display this buffer.
7181
7182 ** It is now meaningful to compare two window-configuration objects
7183 with `equal'. Two window-configuration objects are equal if they
7184 describe equivalent arrangements of windows, in the same frame--in
7185 other words, if they would give the same results if passed to
7186 set-window-configuration.
7187
7188 ** compare-window-configurations is a new function that compares two
7189 window configurations loosely. It ignores differences in saved buffer
7190 positions and scrolling, and considers only the structure and sizes of
7191 windows and the choice of buffers to display.
7192
7193 ** The variable minor-mode-overriding-map-alist allows major modes to
7194 override the key bindings of a minor mode. The elements of this alist
7195 look like the elements of minor-mode-map-alist: (VARIABLE . KEYMAP).
7196
7197 If the VARIABLE in an element of minor-mode-overriding-map-alist has a
7198 non-nil value, the paired KEYMAP is active, and totally overrides the
7199 map (if any) specified for the same variable in minor-mode-map-alist.
7200
7201 minor-mode-overriding-map-alist is automatically local in all buffers,
7202 and it is meant to be set by major modes.
7203
7204 ** The function match-string-no-properties is like match-string
7205 except that it discards all text properties from the result.
7206
7207 ** The function load-average now accepts an optional argument
7208 USE-FLOATS. If it is non-nil, the load average values are returned as
7209 floating point numbers, rather than as integers to be divided by 100.
7210
7211 ** The new variable temporary-file-directory specifies the directory
7212 to use for creating temporary files. The default value is determined
7213 in a reasonable way for your operating system; on GNU and Unix systems
7214 it is based on the TMP and TMPDIR environment variables.
7215
7216 ** Menu changes
7217
7218 *** easymenu.el now uses the new menu item format and supports the
7219 keywords :visible and :filter. The existing keyword :keys is now
7220 better supported.
7221
7222 The variable `easy-menu-precalculate-equivalent-keybindings' controls
7223 a new feature which calculates keyboard equivalents for the menu when
7224 you define the menu. The default is t. If you rarely use menus, you
7225 can set the variable to nil to disable this precalculation feature;
7226 then the calculation is done only if you use the menu bar.
7227
7228 *** A new format for menu items is supported.
7229
7230 In a keymap, a key binding that has the format
7231 (STRING . REAL-BINDING) or (STRING HELP-STRING . REAL-BINDING)
7232 defines a menu item. Now a menu item definition may also be a list that
7233 starts with the symbol `menu-item'.
7234
7235 The format is:
7236 (menu-item ITEM-NAME) or
7237 (menu-item ITEM-NAME REAL-BINDING . ITEM-PROPERTY-LIST)
7238 where ITEM-NAME is an expression which evaluates to the menu item
7239 string, and ITEM-PROPERTY-LIST has the form of a property list.
7240 The supported properties include
7241
7242 :enable FORM Evaluate FORM to determine whether the
7243 item is enabled.
7244 :visible FORM Evaluate FORM to determine whether the
7245 item should appear in the menu.
7246 :filter FILTER-FN
7247 FILTER-FN is a function of one argument,
7248 which will be REAL-BINDING.
7249 It should return a binding to use instead.
7250 :keys DESCRIPTION
7251 DESCRIPTION is a string that describes an equivalent keyboard
7252 binding for REAL-BINDING. DESCRIPTION is expanded with
7253 `substitute-command-keys' before it is used.
7254 :key-sequence KEY-SEQUENCE
7255 KEY-SEQUENCE is a key-sequence for an equivalent
7256 keyboard binding.
7257 :key-sequence nil
7258 This means that the command normally has no
7259 keyboard equivalent.
7260 :help HELP HELP is the extra help string (not currently used).
7261 :button (TYPE . SELECTED)
7262 TYPE is :toggle or :radio.
7263 SELECTED is a form, to be evaluated, and its
7264 value says whether this button is currently selected.
7265
7266 Buttons are at the moment only simulated by prefixes in the menu.
7267 Eventually ordinary X-buttons may be supported.
7268
7269 (menu-item ITEM-NAME) defines unselectable item.
7270
7271 ** New event types
7272
7273 *** The new event type `mouse-wheel' is generated by a wheel on a
7274 mouse (such as the MS Intellimouse). The event contains a delta that
7275 corresponds to the amount and direction that the wheel is rotated,
7276 which is typically used to implement a scroll or zoom. The format is:
7277
7278 (mouse-wheel POSITION DELTA)
7279
7280 where POSITION is a list describing the position of the event in the
7281 same format as a mouse-click event, and DELTA is a signed number
7282 indicating the number of increments by which the wheel was rotated. A
7283 negative DELTA indicates that the wheel was rotated backwards, towards
7284 the user, and a positive DELTA indicates that the wheel was rotated
7285 forward, away from the user.
7286
7287 As of now, this event type is generated only on MS Windows.
7288
7289 *** The new event type `drag-n-drop' is generated when a group of
7290 files is selected in an application outside of Emacs, and then dragged
7291 and dropped onto an Emacs frame. The event contains a list of
7292 filenames that were dragged and dropped, which are then typically
7293 loaded into Emacs. The format is:
7294
7295 (drag-n-drop POSITION FILES)
7296
7297 where POSITION is a list describing the position of the event in the
7298 same format as a mouse-click event, and FILES is the list of filenames
7299 that were dragged and dropped.
7300
7301 As of now, this event type is generated only on MS Windows.
7302
7303 ** Changes relating to multibyte characters.
7304
7305 *** The variable enable-multibyte-characters is now read-only;
7306 any attempt to set it directly signals an error. The only way
7307 to change this value in an existing buffer is with set-buffer-multibyte.
7308
7309 *** In a string constant, `\ ' now stands for "nothing at all". You
7310 can use it to terminate a hex escape which is followed by a character
7311 that could otherwise be read as part of the hex escape.
7312
7313 *** String indices are now measured in characters, as they were
7314 in Emacs 19 and before.
7315
7316 The function chars-in-string has been deleted.
7317 The function concat-chars has been renamed to `string'.
7318
7319 *** The function set-buffer-multibyte sets the flag in the current
7320 buffer that says whether the buffer uses multibyte representation or
7321 unibyte representation. If the argument is nil, it selects unibyte
7322 representation. Otherwise it selects multibyte representation.
7323
7324 This function does not change the contents of the buffer, viewed
7325 as a sequence of bytes. However, it does change the contents
7326 viewed as characters; a sequence of two bytes which is treated as
7327 one character when the buffer uses multibyte representation
7328 will count as two characters using unibyte representation.
7329
7330 This function sets enable-multibyte-characters to record which
7331 representation is in use. It also adjusts various data in the buffer
7332 (including its markers, overlays and text properties) so that they are
7333 consistent with the new representation.
7334
7335 *** string-make-multibyte takes a string and converts it to multibyte
7336 representation. Most of the time, you don't need to care
7337 about the representation, because Emacs converts when necessary;
7338 however, it makes a difference when you compare strings.
7339
7340 The conversion of non-ASCII characters works by adding the value of
7341 nonascii-insert-offset to each character, or by translating them
7342 using the table nonascii-translation-table.
7343
7344 *** string-make-unibyte takes a string and converts it to unibyte
7345 representation. Most of the time, you don't need to care about the
7346 representation, but it makes a difference when you compare strings.
7347
7348 The conversion from multibyte to unibyte representation
7349 loses information; the only time Emacs performs it automatically
7350 is when inserting a multibyte string into a unibyte buffer.
7351
7352 *** string-as-multibyte takes a string, and returns another string
7353 which contains the same bytes, but treats them as multibyte.
7354
7355 *** string-as-unibyte takes a string, and returns another string
7356 which contains the same bytes, but treats them as unibyte.
7357
7358 *** The new function compare-strings lets you compare
7359 portions of two strings. Unibyte strings are converted to multibyte,
7360 so that a unibyte string can match a multibyte string.
7361 You can specify whether to ignore case or not.
7362
7363 *** assoc-ignore-case now uses compare-strings so that
7364 it can treat unibyte and multibyte strings as equal.
7365
7366 *** Regular expression operations and buffer string searches now
7367 convert the search pattern to multibyte or unibyte to accord with the
7368 buffer or string being searched.
7369
7370 One consequence is that you cannot always use \200-\377 inside of
7371 [...] to match all non-ASCII characters. This does still work when
7372 searching or matching a unibyte buffer or string, but not when
7373 searching or matching a multibyte string. Unfortunately, there is no
7374 obvious choice of syntax to use within [...] for that job. But, what
7375 you want is just to match all non-ASCII characters, the regular
7376 expression [^\0-\177] works for it.
7377
7378 *** Structure of coding system changed.
7379
7380 All coding systems (including aliases and subsidiaries) are named
7381 by symbols; the symbol's `coding-system' property is a vector
7382 which defines the coding system. Aliases share the same vector
7383 as the principal name, so that altering the contents of this
7384 vector affects the principal name and its aliases. You can define
7385 your own alias name of a coding system by the function
7386 define-coding-system-alias.
7387
7388 The coding system definition includes a property list of its own. Use
7389 the new functions `coding-system-get' and `coding-system-put' to
7390 access such coding system properties as post-read-conversion,
7391 pre-write-conversion, character-translation-table-for-decode,
7392 character-translation-table-for-encode, mime-charset, and
7393 safe-charsets. For instance, (coding-system-get 'iso-latin-1
7394 'mime-charset) gives the corresponding MIME-charset parameter
7395 `iso-8859-1'.
7396
7397 Among the coding system properties listed above, safe-charsets is new.
7398 The value of this property is a list of character sets which this
7399 coding system can correctly encode and decode. For instance:
7400 (coding-system-get 'iso-latin-1 'safe-charsets) => (ascii latin-iso8859-1)
7401
7402 Here, "correctly encode" means that the encoded character sets can
7403 also be handled safely by systems other than Emacs as far as they
7404 are capable of that coding system. Though, Emacs itself can encode
7405 the other character sets and read it back correctly.
7406
7407 *** The new function select-safe-coding-system can be used to find a
7408 proper coding system for encoding the specified region or string.
7409 This function requires a user interaction.
7410
7411 *** The new functions find-coding-systems-region and
7412 find-coding-systems-string are helper functions used by
7413 select-safe-coding-system. They return a list of all proper coding
7414 systems to encode a text in some region or string. If you don't want
7415 a user interaction, use one of these functions instead of
7416 select-safe-coding-system.
7417
7418 *** The explicit encoding and decoding functions, such as
7419 decode-coding-region and encode-coding-string, now set
7420 last-coding-system-used to reflect the actual way encoding or decoding
7421 was done.
7422
7423 *** The new function detect-coding-with-language-environment can be
7424 used to detect a coding system of text according to priorities of
7425 coding systems used by some specific language environment.
7426
7427 *** The functions detect-coding-region and detect-coding-string always
7428 return a list if the arg HIGHEST is nil. Thus, if only ASCII
7429 characters are found, they now return a list of single element
7430 `undecided' or its subsidiaries.
7431
7432 *** The new functions coding-system-change-eol-conversion and
7433 coding-system-change-text-conversion can be used to get a different
7434 coding system than what specified only in how end-of-line or text is
7435 converted.
7436
7437 *** The new function set-selection-coding-system can be used to set a
7438 coding system for communicating with other X clients.
7439
7440 *** The function `map-char-table' now passes as argument only valid
7441 character codes, plus generic characters that stand for entire
7442 character sets or entire subrows of a character set. In other words,
7443 each time `map-char-table' calls its FUNCTION argument, the key value
7444 either will be a valid individual character code, or will stand for a
7445 range of characters.
7446
7447 *** The new function `char-valid-p' can be used for checking whether a
7448 Lisp object is a valid character code or not.
7449
7450 *** The new function `charset-after' returns a charset of a character
7451 in the current buffer at position POS.
7452
7453 *** Input methods are now implemented using the variable
7454 input-method-function. If this is non-nil, its value should be a
7455 function; then, whenever Emacs reads an input event that is a printing
7456 character with no modifier bits, it calls that function, passing the
7457 event as an argument. Often this function will read more input, first
7458 binding input-method-function to nil.
7459
7460 The return value should be a list of the events resulting from input
7461 method processing. These events will be processed sequentially as
7462 input, before resorting to unread-command-events. Events returned by
7463 the input method function are not passed to the input method function,
7464 not even if they are printing characters with no modifier bits.
7465
7466 The input method function is not called when reading the second and
7467 subsequent events of a key sequence.
7468
7469 *** You can customize any language environment by using
7470 set-language-environment-hook and exit-language-environment-hook.
7471
7472 The hook `exit-language-environment-hook' should be used to undo
7473 customizations that you made with set-language-environment-hook. For
7474 instance, if you set up a special key binding for a specific language
7475 environment by set-language-environment-hook, you should set up
7476 exit-language-environment-hook to restore the normal key binding.
7477 \f
7478 * Changes in Emacs 20.1
7479
7480 ** Emacs has a new facility for customization of its many user
7481 options. It is called M-x customize. With this facility you can look
7482 at the many user options in an organized way; they are grouped into a
7483 tree structure.
7484
7485 M-x customize also knows what sorts of values are legitimate for each
7486 user option and ensures that you don't use invalid values.
7487
7488 With M-x customize, you can set options either for the present Emacs
7489 session or permanently. (Permanent settings are stored automatically
7490 in your .emacs file.)
7491
7492 ** Scroll bars are now on the left side of the window.
7493 You can change this with M-x customize-option scroll-bar-mode.
7494
7495 ** The mode line no longer includes the string `Emacs'.
7496 This makes more space in the mode line for other information.
7497
7498 ** When you select a region with the mouse, it is highlighted
7499 immediately afterward. At that time, if you type the DELETE key, it
7500 kills the region.
7501
7502 The BACKSPACE key, and the ASCII character DEL, do not do this; they
7503 delete the character before point, as usual.
7504
7505 ** In an incremental search the whole current match is highlighted
7506 on terminals which support this. (You can disable this feature
7507 by setting search-highlight to nil.)
7508
7509 ** In the minibuffer, in some cases, you can now use M-n to
7510 insert the default value into the minibuffer as text. In effect,
7511 the default value (if the minibuffer routines know it) is tacked
7512 onto the history "in the future". (The more normal use of the
7513 history list is to use M-p to insert minibuffer input used in the
7514 past.)
7515
7516 ** In Text mode, now only blank lines separate paragraphs.
7517 This makes it possible to get the full benefit of Adaptive Fill mode
7518 in Text mode, and other modes derived from it (such as Mail mode).
7519 TAB in Text mode now runs the command indent-relative; this
7520 makes a practical difference only when you use indented paragraphs.
7521
7522 As a result, the old Indented Text mode is now identical to Text mode,
7523 and is an alias for it.
7524
7525 If you want spaces at the beginning of a line to start a paragraph,
7526 use the new mode, Paragraph Indent Text mode.
7527
7528 ** Scrolling changes
7529
7530 *** Scroll commands to scroll a whole screen now preserve the screen
7531 position of the cursor, if scroll-preserve-screen-position is non-nil.
7532
7533 In this mode, if you scroll several screens back and forth, finishing
7534 on the same screen where you started, the cursor goes back to the line
7535 where it started.
7536
7537 *** If you set scroll-conservatively to a small number, then when you
7538 move point a short distance off the screen, Emacs will scroll the
7539 screen just far enough to bring point back on screen, provided that
7540 does not exceed `scroll-conservatively' lines.
7541
7542 *** The new variable scroll-margin says how close point can come to the
7543 top or bottom of a window. It is a number of screen lines; if point
7544 comes within that many lines of the top or bottom of the window, Emacs
7545 recenters the window.
7546
7547 ** International character set support (MULE)
7548
7549 Emacs now supports a wide variety of international character sets,
7550 including European variants of the Latin alphabet, as well as Chinese,
7551 Devanagari (Hindi and Marathi), Ethiopian, Greek, IPA, Japanese,
7552 Korean, Lao, Russian, Thai, Tibetan, and Vietnamese scripts. These
7553 features have been merged from the modified version of Emacs known as
7554 MULE (for "MULti-lingual Enhancement to GNU Emacs")
7555
7556 Users of these scripts have established many more-or-less standard
7557 coding systems for storing files. Emacs uses a single multibyte
7558 character encoding within Emacs buffers; it can translate from a wide
7559 variety of coding systems when reading a file and can translate back
7560 into any of these coding systems when saving a file.
7561
7562 Keyboards, even in the countries where these character sets are used,
7563 generally don't have keys for all the characters in them. So Emacs
7564 supports various "input methods", typically one for each script or
7565 language, to make it possible to type them.
7566
7567 The Emacs internal multibyte encoding represents a non-ASCII
7568 character as a sequence of bytes in the range 0200 through 0377.
7569
7570 The new prefix key C-x RET is used for commands that pertain
7571 to multibyte characters, coding systems, and input methods.
7572
7573 You can disable multibyte character support as follows:
7574
7575 (setq-default enable-multibyte-characters nil)
7576
7577 Calling the function standard-display-european turns off multibyte
7578 characters, unless you specify a non-nil value for the second
7579 argument, AUTO. This provides compatibility for people who are
7580 already using standard-display-european to continue using unibyte
7581 characters for their work until they want to change.
7582
7583 *** Input methods
7584
7585 An input method is a kind of character conversion which is designed
7586 specifically for interactive input. In Emacs, typically each language
7587 has its own input method (though sometimes several languages which use
7588 the same characters can share one input method). Some languages
7589 support several input methods.
7590
7591 The simplest kind of input method works by mapping ASCII letters into
7592 another alphabet. This is how the Greek and Russian input methods
7593 work.
7594
7595 A more powerful technique is composition: converting sequences of
7596 characters into one letter. Many European input methods use
7597 composition to produce a single non-ASCII letter from a sequence which
7598 consists of a letter followed by diacritics. For example, a' is one
7599 sequence of two characters that might be converted into a single
7600 letter.
7601
7602 The input methods for syllabic scripts typically use mapping followed
7603 by conversion. The input methods for Thai and Korean work this way.
7604 First, letters are mapped into symbols for particular sounds or tone
7605 marks; then, sequences of these which make up a whole syllable are
7606 mapped into one syllable sign--most often a "composite character".
7607
7608 None of these methods works very well for Chinese and Japanese, so
7609 they are handled specially. First you input a whole word using
7610 phonetic spelling; then, after the word is in the buffer, Emacs
7611 converts it into one or more characters using a large dictionary.
7612
7613 Since there is more than one way to represent a phonetically spelled
7614 word using Chinese characters, Emacs can only guess which one to use;
7615 typically these input methods give you a way to say "guess again" if
7616 the first guess is wrong.
7617
7618 *** The command C-x RET m (toggle-enable-multibyte-characters)
7619 turns multibyte character support on or off for the current buffer.
7620
7621 If multibyte character support is turned off in a buffer, then each
7622 byte is a single character, even codes 0200 through 0377--exactly as
7623 they did in Emacs 19.34. This includes the features for support for
7624 the European characters, ISO Latin-1 and ISO Latin-2.
7625
7626 However, there is no need to turn off multibyte character support to
7627 use ISO Latin-1 or ISO Latin-2; the Emacs multibyte character set
7628 includes all the characters in these character sets, and Emacs can
7629 translate automatically to and from either one.
7630
7631 *** Visiting a file in unibyte mode.
7632
7633 Turning off multibyte character support in the buffer after visiting a
7634 file with multibyte code conversion will display the multibyte
7635 sequences already in the buffer, byte by byte. This is probably not
7636 what you want.
7637
7638 If you want to edit a file of unibyte characters (Latin-1, for
7639 example), you can do it by specifying `no-conversion' as the coding
7640 system when reading the file. This coding system also turns off
7641 multibyte characters in that buffer.
7642
7643 If you turn off multibyte character support entirely, this turns off
7644 character conversion as well.
7645
7646 *** Displaying international characters on X Windows.
7647
7648 A font for X typically displays just one alphabet or script.
7649 Therefore, displaying the entire range of characters Emacs supports
7650 requires using many fonts.
7651
7652 Therefore, Emacs now supports "fontsets". Each fontset is a
7653 collection of fonts, each assigned to a range of character codes.
7654
7655 A fontset has a name, like a font. Individual fonts are defined by
7656 the X server; fontsets are defined within Emacs itself. But once you
7657 have defined a fontset, you can use it in a face or a frame just as
7658 you would use a font.
7659
7660 If a fontset specifies no font for a certain character, or if it
7661 specifies a font that does not exist on your system, then it cannot
7662 display that character. It will display an empty box instead.
7663
7664 The fontset height and width are determined by the ASCII characters
7665 (that is, by the font in the fontset which is used for ASCII
7666 characters).
7667
7668 *** Defining fontsets.
7669
7670 Emacs does not use any fontset by default. Its default font is still
7671 chosen as in previous versions. You can tell Emacs to use a fontset
7672 with the `-fn' option or the `Font' X resource.
7673
7674 Emacs creates a standard fontset automatically according to the value
7675 of standard-fontset-spec. This fontset's short name is
7676 `fontset-standard'. Bold, italic, and bold-italic variants of the
7677 standard fontset are created automatically.
7678
7679 If you specify a default ASCII font with the `Font' resource or `-fn'
7680 argument, a fontset is generated from it. This works by replacing the
7681 FOUNDARY, FAMILY, ADD_STYLE, and AVERAGE_WIDTH fields of the font name
7682 with `*' then using this to specify a fontset. This fontset's short
7683 name is `fontset-startup'.
7684
7685 Emacs checks resources of the form Fontset-N where N is 0, 1, 2...
7686 The resource value should have this form:
7687 FONTSET-NAME, [CHARSET-NAME:FONT-NAME]...
7688 FONTSET-NAME should have the form of a standard X font name, except:
7689 * most fields should be just the wild card "*".
7690 * the CHARSET_REGISTRY field should be "fontset"
7691 * the CHARSET_ENCODING field can be any nickname of the fontset.
7692 The construct CHARSET-NAME:FONT-NAME can be repeated any number
7693 of times; each time specifies the font for one character set.
7694 CHARSET-NAME should be the name of a character set, and FONT-NAME
7695 should specify an actual font to use for that character set.
7696
7697 Each of these fontsets has an alias which is made from the
7698 last two font name fields, CHARSET_REGISTRY and CHARSET_ENCODING.
7699 You can refer to the fontset by that alias or by its full name.
7700
7701 For any character sets that you don't mention, Emacs tries to choose a
7702 font by substituting into FONTSET-NAME. For instance, with the
7703 following resource,
7704 Emacs*Fontset-0: -*-fixed-medium-r-normal-*-24-*-*-*-*-*-fontset-24
7705 the font for ASCII is generated as below:
7706 -*-fixed-medium-r-normal-*-24-*-ISO8859-1
7707 Here is the substitution rule:
7708 Change CHARSET_REGISTRY and CHARSET_ENCODING to that of the charset
7709 defined in the variable x-charset-registries. For instance, ASCII has
7710 the entry (ascii . "ISO8859-1") in this variable. Then, reduce
7711 sequences of wild cards -*-...-*- with a single wildcard -*-.
7712 (This is to prevent use of auto-scaled fonts.)
7713
7714 The function which processes the fontset resource value to create the
7715 fontset is called create-fontset-from-fontset-spec. You can also call
7716 that function explicitly to create a fontset.
7717
7718 With the X resource Emacs.Font, you can specify a fontset name just
7719 like an actual font name. But be careful not to specify a fontset
7720 name in a wildcard resource like Emacs*Font--that tries to specify the
7721 fontset for other purposes including menus, and they cannot handle
7722 fontsets.
7723
7724 *** The command M-x set-language-environment sets certain global Emacs
7725 defaults for a particular choice of language.
7726
7727 Selecting a language environment typically specifies a default input
7728 method and which coding systems to recognize automatically when
7729 visiting files. However, it does not try to reread files you have
7730 already visited; the text in those buffers is not affected. The
7731 language environment may also specify a default choice of coding
7732 system for new files that you create.
7733
7734 It makes no difference which buffer is current when you use
7735 set-language-environment, because these defaults apply globally to the
7736 whole Emacs session.
7737
7738 For example, M-x set-language-environment RET Latin-1 RET
7739 chooses the Latin-1 character set. In the .emacs file, you can do this
7740 with (set-language-environment "Latin-1").
7741
7742 *** The command C-x RET f (set-buffer-file-coding-system)
7743 specifies the file coding system for the current buffer. This
7744 specifies what sort of character code translation to do when saving
7745 the file. As an argument, you must specify the name of one of the
7746 coding systems that Emacs supports.
7747
7748 *** The command C-x RET c (universal-coding-system-argument)
7749 lets you specify a coding system when you read or write a file.
7750 This command uses the minibuffer to read a coding system name.
7751 After you exit the minibuffer, the specified coding system
7752 is used for *the immediately following command*.
7753
7754 So if the immediately following command is a command to read or
7755 write a file, it uses the specified coding system for that file.
7756
7757 If the immediately following command does not use the coding system,
7758 then C-x RET c ultimately has no effect.
7759
7760 For example, C-x RET c iso-8859-1 RET C-x C-f temp RET
7761 visits the file `temp' treating it as ISO Latin-1.
7762
7763 *** You can specify the coding system for a file using the -*-
7764 construct. Include `coding: CODINGSYSTEM;' inside the -*-...-*-
7765 to specify use of coding system CODINGSYSTEM. You can also
7766 specify the coding system in a local variable list at the end
7767 of the file.
7768
7769 *** The command C-x RET t (set-terminal-coding-system) specifies
7770 the coding system for terminal output. If you specify a character
7771 code for terminal output, all characters output to the terminal are
7772 translated into that character code.
7773
7774 This feature is useful for certain character-only terminals built in
7775 various countries to support the languages of those countries.
7776
7777 By default, output to the terminal is not translated at all.
7778
7779 *** The command C-x RET k (set-keyboard-coding-system) specifies
7780 the coding system for keyboard input.
7781
7782 Character code translation of keyboard input is useful for terminals
7783 with keys that send non-ASCII graphic characters--for example,
7784 some terminals designed for ISO Latin-1 or subsets of it.
7785
7786 By default, keyboard input is not translated at all.
7787
7788 Character code translation of keyboard input is similar to using an
7789 input method, in that both define sequences of keyboard input that
7790 translate into single characters. However, input methods are designed
7791 to be convenient for interactive use, while the code translations are
7792 designed to work with terminals.
7793
7794 *** The command C-x RET p (set-buffer-process-coding-system)
7795 specifies the coding system for input and output to a subprocess.
7796 This command applies to the current buffer; normally, each subprocess
7797 has its own buffer, and thus you can use this command to specify
7798 translation to and from a particular subprocess by giving the command
7799 in the corresponding buffer.
7800
7801 By default, process input and output are not translated at all.
7802
7803 *** The variable file-name-coding-system specifies the coding system
7804 to use for encoding file names before operating on them.
7805 It is also used for decoding file names obtained from the system.
7806
7807 *** The command C-\ (toggle-input-method) activates or deactivates
7808 an input method. If no input method has been selected before, the
7809 command prompts for you to specify the language and input method you
7810 want to use.
7811
7812 C-u C-\ (select-input-method) lets you switch to a different input
7813 method. C-h C-\ (or C-h I) describes the current input method.
7814
7815 *** Some input methods remap the keyboard to emulate various keyboard
7816 layouts commonly used for particular scripts. How to do this
7817 remapping properly depends on your actual keyboard layout. To specify
7818 which layout your keyboard has, use M-x quail-set-keyboard-layout.
7819
7820 *** The command C-h C (describe-coding-system) displays
7821 the coding systems currently selected for various purposes, plus
7822 related information.
7823
7824 *** The command C-h h (view-hello-file) displays a file called
7825 HELLO, which has examples of text in many languages, using various
7826 scripts.
7827
7828 *** The command C-h L (describe-language-support) displays
7829 information about the support for a particular language.
7830 You specify the language as an argument.
7831
7832 *** The mode line now contains a letter or character that identifies
7833 the coding system used in the visited file. It normally follows the
7834 first dash.
7835
7836 A dash indicates the default state of affairs: no code conversion
7837 (except CRLF => newline if appropriate). `=' means no conversion
7838 whatsoever. The ISO 8859 coding systems are represented by digits
7839 1 through 9. Other coding systems are represented by letters:
7840
7841 A alternativnyj (Russian)
7842 B big5 (Chinese)
7843 C cn-gb-2312 (Chinese)
7844 C iso-2022-cn (Chinese)
7845 D in-is13194-devanagari (Indian languages)
7846 E euc-japan (Japanese)
7847 I iso-2022-cjk or iso-2022-ss2 (Chinese, Japanese, Korean)
7848 J junet (iso-2022-7) or old-jis (iso-2022-jp-1978-irv) (Japanese)
7849 K euc-korea (Korean)
7850 R koi8 (Russian)
7851 Q tibetan
7852 S shift_jis (Japanese)
7853 T lao
7854 T tis620 (Thai)
7855 V viscii or vscii (Vietnamese)
7856 i iso-2022-lock (Chinese, Japanese, Korean)
7857 k iso-2022-kr (Korean)
7858 v viqr (Vietnamese)
7859 z hz (Chinese)
7860
7861 When you are using a character-only terminal (not a window system),
7862 two additional characters appear in between the dash and the file
7863 coding system. These two characters describe the coding system for
7864 keyboard input, and the coding system for terminal output.
7865
7866 *** The new variable rmail-file-coding-system specifies the code
7867 conversion to use for RMAIL files. The default value is nil.
7868
7869 When you read mail with Rmail, each message is decoded automatically
7870 into Emacs' internal format. This has nothing to do with
7871 rmail-file-coding-system. That variable controls reading and writing
7872 Rmail files themselves.
7873
7874 *** The new variable sendmail-coding-system specifies the code
7875 conversion for outgoing mail. The default value is nil.
7876
7877 Actually, there are three different ways of specifying the coding system
7878 for sending mail:
7879
7880 - If you use C-x RET f in the mail buffer, that takes priority.
7881 - Otherwise, if you set sendmail-coding-system non-nil, that specifies it.
7882 - Otherwise, the default coding system for new files is used,
7883 if that is non-nil. That comes from your language environment.
7884 - Otherwise, Latin-1 is used.
7885
7886 *** The command C-h t (help-with-tutorial) accepts a prefix argument
7887 to specify the language for the tutorial file. Currently, English,
7888 Japanese, Korean and Thai are supported. We welcome additional
7889 translations.
7890
7891 ** An easy new way to visit a file with no code or format conversion
7892 of any kind: Use M-x find-file-literally. There is also a command
7893 insert-file-literally which inserts a file into the current buffer
7894 without any conversion.
7895
7896 ** C-q's handling of octal character codes is changed.
7897 You can now specify any number of octal digits.
7898 RET terminates the digits and is discarded;
7899 any other non-digit terminates the digits and is then used as input.
7900
7901 ** There are new commands for looking up Info documentation for
7902 functions, variables and file names used in your programs.
7903
7904 Type M-x info-lookup-symbol to look up a symbol in the buffer at point.
7905 Type M-x info-lookup-file to look up a file in the buffer at point.
7906
7907 Precisely which Info files are used to look it up depends on the major
7908 mode. For example, in C mode, the GNU libc manual is used.
7909
7910 ** M-TAB in most programming language modes now runs the command
7911 complete-symbol. This command performs completion on the symbol name
7912 in the buffer before point.
7913
7914 With a numeric argument, it performs completion based on the set of
7915 symbols documented in the Info files for the programming language that
7916 you are using.
7917
7918 With no argument, it does completion based on the current tags tables,
7919 just like the old binding of M-TAB (complete-tag).
7920
7921 ** File locking works with NFS now.
7922
7923 The lock file for FILENAME is now a symbolic link named .#FILENAME,
7924 in the same directory as FILENAME.
7925
7926 This means that collision detection between two different machines now
7927 works reasonably well; it also means that no file server or directory
7928 can become a bottleneck.
7929
7930 The new method does have drawbacks. It means that collision detection
7931 does not operate when you edit a file in a directory where you cannot
7932 create new files. Collision detection also doesn't operate when the
7933 file server does not support symbolic links. But these conditions are
7934 rare, and the ability to have collision detection while using NFS is
7935 so useful that the change is worth while.
7936
7937 When Emacs or a system crashes, this may leave behind lock files which
7938 are stale. So you may occasionally get warnings about spurious
7939 collisions. When you determine that the collision is spurious, just
7940 tell Emacs to go ahead anyway.
7941
7942 ** If you wish to use Show Paren mode to display matching parentheses,
7943 it is no longer sufficient to load paren.el. Instead you must call
7944 show-paren-mode.
7945
7946 ** If you wish to use Delete Selection mode to replace a highlighted
7947 selection when you insert new text, it is no longer sufficient to load
7948 delsel.el. Instead you must call the function delete-selection-mode.
7949
7950 ** If you wish to use Partial Completion mode to complete partial words
7951 within symbols or filenames, it is no longer sufficient to load
7952 complete.el. Instead you must call the function partial-completion-mode.
7953
7954 ** If you wish to use uniquify to rename buffers for you,
7955 it is no longer sufficient to load uniquify.el. You must also
7956 set uniquify-buffer-name-style to one of the non-nil legitimate values.
7957
7958 ** Changes in View mode.
7959
7960 *** Several new commands are available in View mode.
7961 Do H in view mode for a list of commands.
7962
7963 *** There are two new commands for entering View mode:
7964 view-file-other-frame and view-buffer-other-frame.
7965
7966 *** Exiting View mode does a better job of restoring windows to their
7967 previous state.
7968
7969 *** New customization variable view-scroll-auto-exit. If non-nil,
7970 scrolling past end of buffer makes view mode exit.
7971
7972 *** New customization variable view-exits-all-viewing-windows. If
7973 non-nil, view-mode will at exit restore all windows viewing buffer,
7974 not just the selected window.
7975
7976 *** New customization variable view-read-only. If non-nil, visiting a
7977 read-only file automatically enters View mode, and toggle-read-only
7978 turns View mode on or off.
7979
7980 *** New customization variable view-remove-frame-by-deleting controls
7981 how to remove a not needed frame at view mode exit. If non-nil,
7982 delete the frame, if nil make an icon of it.
7983
7984 ** C-x v l, the command to print a file's version control log,
7985 now positions point at the entry for the file's current branch version.
7986
7987 ** C-x v =, the command to compare a file with the last checked-in version,
7988 has a new feature. If the file is currently not locked, so that it is
7989 presumably identical to the last checked-in version, the command now asks
7990 which version to compare with.
7991
7992 ** When using hideshow.el, incremental search can temporarily show hidden
7993 blocks if a match is inside the block.
7994
7995 The block is hidden again if the search is continued and the next match
7996 is outside the block. By customizing the variable
7997 isearch-hide-immediately you can choose to hide all the temporarily
7998 shown blocks only when exiting from incremental search.
7999
8000 By customizing the variable hs-isearch-open you can choose what kind
8001 of blocks to temporarily show during isearch: comment blocks, code
8002 blocks, all of them or none.
8003
8004 ** The new command C-x 4 0 (kill-buffer-and-window) kills the
8005 current buffer and deletes the selected window. It asks for
8006 confirmation first.
8007
8008 ** C-x C-w, which saves the buffer into a specified file name,
8009 now changes the major mode according to that file name.
8010 However, the mode will not be changed if
8011 (1) a local variables list or the `-*-' line specifies a major mode, or
8012 (2) the current major mode is a "special" mode,
8013 not suitable for ordinary files, or
8014 (3) the new file name does not particularly specify any mode.
8015
8016 This applies to M-x set-visited-file-name as well.
8017
8018 However, if you set change-major-mode-with-file-name to nil, then
8019 these commands do not change the major mode.
8020
8021 ** M-x occur changes.
8022
8023 *** If the argument to M-x occur contains upper case letters,
8024 it performs a case-sensitive search.
8025
8026 *** In the *Occur* buffer made by M-x occur,
8027 if you type g or M-x revert-buffer, this repeats the search
8028 using the same regular expression and the same buffer as before.
8029
8030 ** In Transient Mark mode, the region in any one buffer is highlighted
8031 in just one window at a time. At first, it is highlighted in the
8032 window where you set the mark. The buffer's highlighting remains in
8033 that window unless you select to another window which shows the same
8034 buffer--then the highlighting moves to that window.
8035
8036 ** The feature to suggest key bindings when you use M-x now operates
8037 after the command finishes. The message suggesting key bindings
8038 appears temporarily in the echo area. The previous echo area contents
8039 come back after a few seconds, in case they contain useful information.
8040
8041 ** Each frame now independently records the order for recently
8042 selected buffers, so that the default for C-x b is now based on the
8043 buffers recently selected in the selected frame.
8044
8045 ** Outline mode changes.
8046
8047 *** Outline mode now uses overlays (this is the former noutline.el).
8048
8049 *** Incremental searches skip over invisible text in Outline mode.
8050
8051 ** When a minibuffer window is active but not the selected window, if
8052 you try to use the minibuffer, you used to get a nested minibuffer.
8053 Now, this not only gives an error, it also cancels the minibuffer that
8054 was already active.
8055
8056 The motive for this change is so that beginning users do not
8057 unknowingly move away from minibuffers, leaving them active, and then
8058 get confused by it.
8059
8060 If you want to be able to have recursive minibuffers, you must
8061 set enable-recursive-minibuffers to non-nil.
8062
8063 ** Changes in dynamic abbrevs.
8064
8065 *** Expanding dynamic abbrevs with M-/ is now smarter about case
8066 conversion. If the expansion has mixed case not counting the first
8067 character, and the abbreviation matches the beginning of the expansion
8068 including case, then the expansion is copied verbatim.
8069
8070 The expansion is also copied verbatim if the abbreviation itself has
8071 mixed case. And using SPC M-/ to copy an additional word always
8072 copies it verbatim except when the previous copied word is all caps.
8073
8074 *** The values of `dabbrev-case-replace' and `dabbrev-case-fold-search'
8075 are no longer Lisp expressions. They have simply three possible
8076 values.
8077
8078 `dabbrev-case-replace' has these three values: nil (don't preserve
8079 case), t (do), or `case-replace' (do like M-x query-replace).
8080 `dabbrev-case-fold-search' has these three values: nil (don't ignore
8081 case), t (do), or `case-fold-search' (do like search).
8082
8083 ** Minibuffer history lists are truncated automatically now to a
8084 certain length. The variable history-length specifies how long they
8085 can be. The default value is 30.
8086
8087 ** Changes in Mail mode.
8088
8089 *** The key C-x m no longer runs the `mail' command directly.
8090 Instead, it runs the command `compose-mail', which invokes the mail
8091 composition mechanism you have selected with the variable
8092 `mail-user-agent'. The default choice of user agent is
8093 `sendmail-user-agent', which gives behavior compatible with the old
8094 behavior.
8095
8096 C-x 4 m now runs compose-mail-other-window, and C-x 5 m runs
8097 compose-mail-other-frame.
8098
8099 *** While composing a reply to a mail message, from Rmail, you can use
8100 the command C-c C-r to cite just the region from the message you are
8101 replying to. This copies the text which is the selected region in the
8102 buffer that shows the original message.
8103
8104 *** The command C-c C-i inserts a file at the end of the message,
8105 with separator lines around the contents.
8106
8107 *** The command M-x expand-mail-aliases expands all mail aliases
8108 in suitable mail headers. Emacs automatically extracts mail alias
8109 definitions from your mail alias file (e.g., ~/.mailrc). You do not
8110 need to expand mail aliases yourself before sending mail.
8111
8112 *** New features in the mail-complete command.
8113
8114 **** The mail-complete command now inserts the user's full name,
8115 for local users or if that is known. The variable mail-complete-style
8116 controls the style to use, and whether to do this at all.
8117 Its values are like those of mail-from-style.
8118
8119 **** The variable mail-passwd-command lets you specify a shell command
8120 to run to fetch a set of password-entries that add to the ones in
8121 /etc/passwd.
8122
8123 **** The variable mail-passwd-file now specifies a list of files to read
8124 to get the list of user ids. By default, one file is used:
8125 /etc/passwd.
8126
8127 ** You can "quote" a file name to inhibit special significance of
8128 special syntax, by adding `/:' to the beginning. Thus, if you have a
8129 directory named `/foo:', you can prevent it from being treated as a
8130 reference to a remote host named `foo' by writing it as `/:/foo:'.
8131
8132 Emacs uses this new construct automatically when necessary, such as
8133 when you start it with a working directory whose name might otherwise
8134 be taken to be magic.
8135
8136 ** There is a new command M-x grep-find which uses find to select
8137 files to search through, and grep to scan them. The output is
8138 available in a Compile mode buffer, as with M-x grep.
8139
8140 M-x grep now uses the -e option if the grep program supports that.
8141 (-e prevents problems if the search pattern starts with a dash.)
8142
8143 ** In Dired, the & command now flags for deletion the files whose names
8144 suggest they are probably not needed in the long run.
8145
8146 In Dired, * is now a prefix key for mark-related commands.
8147
8148 new key dired.el binding old key
8149 ------- ---------------- -------
8150 * c dired-change-marks c
8151 * m dired-mark m
8152 * * dired-mark-executables * (binding deleted)
8153 * / dired-mark-directories / (binding deleted)
8154 * @ dired-mark-symlinks @ (binding deleted)
8155 * u dired-unmark u
8156 * DEL dired-unmark-backward DEL
8157 * ? dired-unmark-all-files C-M-?
8158 * ! dired-unmark-all-marks
8159 * % dired-mark-files-regexp % m
8160 * C-n dired-next-marked-file M-}
8161 * C-p dired-prev-marked-file M-{
8162
8163 ** Rmail changes.
8164
8165 *** When Rmail cannot convert your incoming mail into Babyl format, it
8166 saves the new mail in the file RMAILOSE.n, where n is an integer
8167 chosen to make a unique name. This way, Rmail will not keep crashing
8168 each time you run it.
8169
8170 *** In Rmail, the variable rmail-summary-line-count-flag now controls
8171 whether to include the line count in the summary. Non-nil means yes.
8172
8173 *** In Rmail summary buffers, d and C-d (the commands to delete
8174 messages) now take repeat counts as arguments. A negative argument
8175 means to move in the opposite direction.
8176
8177 *** In Rmail, the t command now takes an optional argument which lets
8178 you specify whether to show the message headers in full or pruned.
8179
8180 *** In Rmail, the new command w (rmail-output-body-to-file) writes
8181 just the body of the current message into a file, without the headers.
8182 It takes the file name from the message subject, by default, but you
8183 can edit that file name in the minibuffer before it is actually used
8184 for output.
8185
8186 ** Gnus changes.
8187
8188 *** nntp.el has been totally rewritten in an asynchronous fashion.
8189
8190 *** Article prefetching functionality has been moved up into
8191 Gnus.
8192
8193 *** Scoring can now be performed with logical operators like
8194 `and', `or', `not', and parent redirection.
8195
8196 *** Article washing status can be displayed in the
8197 article mode line.
8198
8199 *** gnus.el has been split into many smaller files.
8200
8201 *** Suppression of duplicate articles based on Message-ID.
8202
8203 (setq gnus-suppress-duplicates t)
8204
8205 *** New variables for specifying what score and adapt files
8206 are to be considered home score and adapt files. See
8207 `gnus-home-score-file' and `gnus-home-adapt-files'.
8208
8209 *** Groups can inherit group parameters from parent topics.
8210
8211 *** Article editing has been revamped and is now usable.
8212
8213 *** Signatures can be recognized in more intelligent fashions.
8214 See `gnus-signature-separator' and `gnus-signature-limit'.
8215
8216 *** Summary pick mode has been made to look more nn-like.
8217 Line numbers are displayed and the `.' command can be
8218 used to pick articles.
8219
8220 *** Commands for moving the .newsrc.eld from one server to
8221 another have been added.
8222
8223 `M-x gnus-change-server'
8224
8225 *** A way to specify that "uninteresting" fields be suppressed when
8226 generating lines in buffers.
8227
8228 *** Several commands in the group buffer can be undone with
8229 `C-M-_'.
8230
8231 *** Scoring can be done on words using the new score type `w'.
8232
8233 *** Adaptive scoring can be done on a Subject word-by-word basis:
8234
8235 (setq gnus-use-adaptive-scoring '(word))
8236
8237 *** Scores can be decayed.
8238
8239 (setq gnus-decay-scores t)
8240
8241 *** Scoring can be performed using a regexp on the Date header. The
8242 Date is normalized to compact ISO 8601 format first.
8243
8244 *** A new command has been added to remove all data on articles from
8245 the native server.
8246
8247 `M-x gnus-group-clear-data-on-native-groups'
8248
8249 *** A new command for reading collections of documents
8250 (nndoc with nnvirtual on top) has been added -- `C-M-d'.
8251
8252 *** Process mark sets can be pushed and popped.
8253
8254 *** A new mail-to-news backend makes it possible to post
8255 even when the NNTP server doesn't allow posting.
8256
8257 *** A new backend for reading searches from Web search engines
8258 (DejaNews, Alta Vista, InReference) has been added.
8259
8260 Use the `G w' command in the group buffer to create such
8261 a group.
8262
8263 *** Groups inside topics can now be sorted using the standard
8264 sorting functions, and each topic can be sorted independently.
8265
8266 See the commands under the `T S' submap.
8267
8268 *** Subsets of the groups can be sorted independently.
8269
8270 See the commands under the `G P' submap.
8271
8272 *** Cached articles can be pulled into the groups.
8273
8274 Use the `Y c' command.
8275
8276 *** Score files are now applied in a more reliable order.
8277
8278 *** Reports on where mail messages end up can be generated.
8279
8280 `M-x nnmail-split-history'
8281
8282 *** More hooks and functions have been added to remove junk
8283 from incoming mail before saving the mail.
8284
8285 See `nnmail-prepare-incoming-header-hook'.
8286
8287 *** The nnml mail backend now understands compressed article files.
8288
8289 *** To enable Gnus to read/post multi-lingual articles, you must execute
8290 the following code, for instance, in your .emacs.
8291
8292 (add-hook 'gnus-startup-hook 'gnus-mule-initialize)
8293
8294 Then, when you start Gnus, it will decode non-ASCII text automatically
8295 and show appropriate characters. (Note: if you are using gnus-mime
8296 from the SEMI package, formerly known as TM, you should NOT add this
8297 hook to gnus-startup-hook; gnus-mime has its own method of handling
8298 this issue.)
8299
8300 Since it is impossible to distinguish all coding systems
8301 automatically, you may need to specify a choice of coding system for a
8302 particular news group. This can be done by:
8303
8304 (gnus-mule-add-group NEWSGROUP 'CODING-SYSTEM)
8305
8306 Here NEWSGROUP should be a string which names a newsgroup or a tree
8307 of newsgroups. If NEWSGROUP is "XXX.YYY", all news groups under
8308 "XXX.YYY" (including "XXX.YYY.ZZZ") will use the specified coding
8309 system. CODING-SYSTEM specifies which coding system to use (for both
8310 for reading and posting).
8311
8312 CODING-SYSTEM can also be a cons cell of the form
8313 (READ-CODING-SYSTEM . POST-CODING-SYSTEM)
8314 Then READ-CODING-SYSTEM is used when you read messages from the
8315 newsgroups, while POST-CODING-SYSTEM is used when you post messages
8316 there.
8317
8318 Emacs knows the right coding systems for certain newsgroups by
8319 default. Here are some of these default settings:
8320
8321 (gnus-mule-add-group "fj" 'iso-2022-7)
8322 (gnus-mule-add-group "alt.chinese.text" 'hz-gb-2312)
8323 (gnus-mule-add-group "alt.hk" 'hz-gb-2312)
8324 (gnus-mule-add-group "alt.chinese.text.big5" 'cn-big5)
8325 (gnus-mule-add-group "soc.culture.vietnamese" '(nil . viqr))
8326
8327 When you reply by mail to an article, these settings are ignored;
8328 the mail is encoded according to sendmail-coding-system, as usual.
8329
8330 ** CC mode changes.
8331
8332 *** If you edit primarily one style of C (or C++, Objective-C, Java)
8333 code, you may want to make the CC Mode style variables have global
8334 values so that you can set them directly in your .emacs file. To do
8335 this, set c-style-variables-are-local-p to nil in your .emacs file.
8336 Note that this only takes effect if you do it *before* cc-mode.el is
8337 loaded.
8338
8339 If you typically edit more than one style of C (or C++, Objective-C,
8340 Java) code in a single Emacs session, you may want to make the CC Mode
8341 style variables have buffer local values. By default, all buffers
8342 share the same style variable settings; to make them buffer local, set
8343 c-style-variables-are-local-p to t in your .emacs file. Note that you
8344 must do this *before* CC Mode is loaded.
8345
8346 *** The new variable c-indentation-style holds the C style name
8347 of the current buffer.
8348
8349 *** The variable c-block-comments-indent-p has been deleted, because
8350 it is no longer necessary. C mode now handles all the supported styles
8351 of block comments, with no need to say which one you will use.
8352
8353 *** There is a new indentation style "python", which specifies the C
8354 style that the Python developers like.
8355
8356 *** There is a new c-cleanup-list option: brace-elseif-brace.
8357 This says to put ...} else if (...) {... on one line,
8358 just as brace-else-brace says to put ...} else {... on one line.
8359
8360 ** VC Changes [new]
8361
8362 *** In vc-retrieve-snapshot (C-x v r), if you don't specify a snapshot
8363 name, it retrieves the *latest* versions of all files in the current
8364 directory and its subdirectories (aside from files already locked).
8365
8366 This feature is useful if your RCS directory is a link to a common
8367 master directory, and you want to pick up changes made by other
8368 developers.
8369
8370 You can do the same thing for an individual file by typing C-u C-x C-q
8371 RET in a buffer visiting that file.
8372
8373 *** VC can now handle files under CVS that are being "watched" by
8374 other developers. Such files are made read-only by CVS. To get a
8375 writable copy, type C-x C-q in a buffer visiting such a file. VC then
8376 calls "cvs edit", which notifies the other developers of it.
8377
8378 *** vc-version-diff (C-u C-x v =) now suggests reasonable defaults for
8379 version numbers, based on the current state of the file.
8380
8381 ** Calendar changes.
8382
8383 *** A new function, list-holidays, allows you list holidays or
8384 subclasses of holidays for ranges of years. Related menu items allow
8385 you do this for the year of the selected date, or the
8386 following/previous years.
8387
8388 *** There is now support for the Baha'i calendar system. Use `pb' in
8389 the *Calendar* buffer to display the current Baha'i date. The Baha'i
8390 calendar, or "Badi calendar" is a system of 19 months with 19 days
8391 each, and 4 intercalary days (5 during a Gregorian leap year). The
8392 calendar begins May 23, 1844, with each of the months named after a
8393 supposed attribute of God.
8394
8395 ** ps-print changes
8396
8397 There are some new user variables and subgroups for customizing the page
8398 layout.
8399
8400 *** Headers & Footers (subgroup)
8401
8402 Some printer systems print a header page and force the first page to
8403 be printed on the back of the header page when using duplex. If your
8404 printer system has this behavior, set variable
8405 `ps-banner-page-when-duplexing' to t.
8406
8407 If variable `ps-banner-page-when-duplexing' is non-nil, it prints a
8408 blank page as the very first printed page. So, it behaves as if the
8409 very first character of buffer (or region) were a form feed ^L (\014).
8410
8411 The variable `ps-spool-config' specifies who is responsible for
8412 setting duplex mode and page size. Valid values are:
8413
8414 lpr-switches duplex and page size are configured by `ps-lpr-switches'.
8415 Don't forget to set `ps-lpr-switches' to select duplex
8416 printing for your printer.
8417
8418 setpagedevice duplex and page size are configured by ps-print using the
8419 setpagedevice PostScript operator.
8420
8421 nil duplex and page size are configured by ps-print *not* using
8422 the setpagedevice PostScript operator.
8423
8424 The variable `ps-spool-tumble' specifies how the page images on
8425 opposite sides of a sheet are oriented with respect to each other. If
8426 `ps-spool-tumble' is nil, ps-print produces output suitable for
8427 bindings on the left or right. If `ps-spool-tumble' is non-nil,
8428 ps-print produces output suitable for bindings at the top or bottom.
8429 This variable takes effect only if `ps-spool-duplex' is non-nil.
8430 The default value is nil.
8431
8432 The variable `ps-header-frame-alist' specifies a header frame
8433 properties alist. Valid frame properties are:
8434
8435 fore-color Specify the foreground frame color.
8436 Value should be a float number between 0.0 (black
8437 color) and 1.0 (white color), or a string which is a
8438 color name, or a list of 3 float numbers which
8439 correspond to the Red Green Blue color scale, each
8440 float number between 0.0 (dark color) and 1.0 (bright
8441 color). The default is 0 ("black").
8442
8443 back-color Specify the background frame color (similar to fore-color).
8444 The default is 0.9 ("gray90").
8445
8446 shadow-color Specify the shadow color (similar to fore-color).
8447 The default is 0 ("black").
8448
8449 border-color Specify the border color (similar to fore-color).
8450 The default is 0 ("black").
8451
8452 border-width Specify the border width.
8453 The default is 0.4.
8454
8455 Any other property is ignored.
8456
8457 Don't change this alist directly; instead use Custom, or the
8458 `ps-value', `ps-get', `ps-put' and `ps-del' functions (see there for
8459 documentation).
8460
8461 Ps-print can also print footers. The footer variables are:
8462 `ps-print-footer', `ps-footer-offset', `ps-print-footer-frame',
8463 `ps-footer-font-family', `ps-footer-font-size', `ps-footer-line-pad',
8464 `ps-footer-lines', `ps-left-footer', `ps-right-footer' and
8465 `ps-footer-frame-alist'. These variables are similar to those
8466 controlling headers.
8467
8468 *** Color management (subgroup)
8469
8470 If `ps-print-color-p' is non-nil, the buffer's text will be printed in
8471 color.
8472
8473 *** Face Management (subgroup)
8474
8475 If you need to print without worrying about face background colors,
8476 set the variable `ps-use-face-background' which specifies if face
8477 background should be used. Valid values are:
8478
8479 t always use face background color.
8480 nil never use face background color.
8481 (face...) list of faces whose background color will be used.
8482
8483 *** N-up printing (subgroup)
8484
8485 The variable `ps-n-up-printing' specifies the number of pages per
8486 sheet of paper.
8487
8488 The variable `ps-n-up-margin' specifies the margin in points (pt)
8489 between the sheet border and the n-up printing.
8490
8491 If variable `ps-n-up-border-p' is non-nil, a border is drawn around
8492 each page.
8493
8494 The variable `ps-n-up-filling' specifies how the page matrix is filled
8495 on each sheet of paper. Following are the valid values for
8496 `ps-n-up-filling' with a filling example using a 3x4 page matrix:
8497
8498 `left-top' 1 2 3 4 `left-bottom' 9 10 11 12
8499 5 6 7 8 5 6 7 8
8500 9 10 11 12 1 2 3 4
8501
8502 `right-top' 4 3 2 1 `right-bottom' 12 11 10 9
8503 8 7 6 5 8 7 6 5
8504 12 11 10 9 4 3 2 1
8505
8506 `top-left' 1 4 7 10 `bottom-left' 3 6 9 12
8507 2 5 8 11 2 5 8 11
8508 3 6 9 12 1 4 7 10
8509
8510 `top-right' 10 7 4 1 `bottom-right' 12 9 6 3
8511 11 8 5 2 11 8 5 2
8512 12 9 6 3 10 7 4 1
8513
8514 Any other value is treated as `left-top'.
8515
8516 *** Zebra stripes (subgroup)
8517
8518 The variable `ps-zebra-color' controls the zebra stripes grayscale or
8519 RGB color.
8520
8521 The variable `ps-zebra-stripe-follow' specifies how zebra stripes
8522 continue on next page. Visually, valid values are (the character `+'
8523 to the right of each column indicates that a line is printed):
8524
8525 `nil' `follow' `full' `full-follow'
8526 Current Page -------- ----------- --------- ----------------
8527 1 XXXXX + 1 XXXXXXXX + 1 XXXXXX + 1 XXXXXXXXXXXXX +
8528 2 XXXXX + 2 XXXXXXXX + 2 XXXXXX + 2 XXXXXXXXXXXXX +
8529 3 XXXXX + 3 XXXXXXXX + 3 XXXXXX + 3 XXXXXXXXXXXXX +
8530 4 + 4 + 4 + 4 +
8531 5 + 5 + 5 + 5 +
8532 6 + 6 + 6 + 6 +
8533 7 XXXXX + 7 XXXXXXXX + 7 XXXXXX + 7 XXXXXXXXXXXXX +
8534 8 XXXXX + 8 XXXXXXXX + 8 XXXXXX + 8 XXXXXXXXXXXXX +
8535 9 XXXXX + 9 XXXXXXXX + 9 XXXXXX + 9 XXXXXXXXXXXXX +
8536 10 + 10 +
8537 11 + 11 +
8538 -------- ----------- --------- ----------------
8539 Next Page -------- ----------- --------- ----------------
8540 12 XXXXX + 12 + 10 XXXXXX + 10 +
8541 13 XXXXX + 13 XXXXXXXX + 11 XXXXXX + 11 +
8542 14 XXXXX + 14 XXXXXXXX + 12 XXXXXX + 12 +
8543 15 + 15 XXXXXXXX + 13 + 13 XXXXXXXXXXXXX +
8544 16 + 16 + 14 + 14 XXXXXXXXXXXXX +
8545 17 + 17 + 15 + 15 XXXXXXXXXXXXX +
8546 18 XXXXX + 18 + 16 XXXXXX + 16 +
8547 19 XXXXX + 19 XXXXXXXX + 17 XXXXXX + 17 +
8548 20 XXXXX + 20 XXXXXXXX + 18 XXXXXX + 18 +
8549 21 + 21 XXXXXXXX +
8550 22 + 22 +
8551 -------- ----------- --------- ----------------
8552
8553 Any other value is treated as `nil'.
8554
8555
8556 *** Printer management (subgroup)
8557
8558 The variable `ps-printer-name-option' determines the option used by
8559 some utilities to indicate the printer name; it's used only when
8560 `ps-printer-name' is a non-empty string. If you're using the lpr
8561 utility to print, for example, `ps-printer-name-option' should be set
8562 to "-P".
8563
8564 The variable `ps-manual-feed' indicates if the printer requires manual
8565 paper feeding. If it's nil, automatic feeding takes place. If it's
8566 non-nil, manual feeding takes place.
8567
8568 The variable `ps-end-with-control-d' specifies whether C-d (\x04)
8569 should be inserted at end of the generated PostScript. Non-nil means
8570 do so.
8571
8572 *** Page settings (subgroup)
8573
8574 If variable `ps-warn-paper-type' is nil, it's *not* treated as an
8575 error if the PostScript printer doesn't have a paper with the size
8576 indicated by `ps-paper-type'; the default paper size will be used
8577 instead. If `ps-warn-paper-type' is non-nil, an error is signaled if
8578 the PostScript printer doesn't support a paper with the size indicated
8579 by `ps-paper-type'. This is used when `ps-spool-config' is set to
8580 `setpagedevice'.
8581
8582 The variable `ps-print-upside-down' determines the orientation for
8583 printing pages: nil means `normal' printing, non-nil means
8584 `upside-down' printing (that is, the page is rotated by 180 degrees).
8585
8586 The variable `ps-selected-pages' specifies which pages to print. If
8587 it's nil, all pages are printed. If it's a list, list elements may be
8588 integers specifying a single page to print, or cons cells (FROM . TO)
8589 specifying to print from page FROM to TO. Invalid list elements, that
8590 is integers smaller than one, or elements whose FROM is greater than
8591 its TO, are ignored.
8592
8593 The variable `ps-even-or-odd-pages' specifies how to print even/odd
8594 pages. Valid values are:
8595
8596 nil print all pages.
8597
8598 `even-page' print only even pages.
8599
8600 `odd-page' print only odd pages.
8601
8602 `even-sheet' print only even sheets.
8603 That is, if `ps-n-up-printing' is 1, it behaves like
8604 `even-page', but for values greater than 1, it'll
8605 print only the even sheet of paper.
8606
8607 `odd-sheet' print only odd sheets.
8608 That is, if `ps-n-up-printing' is 1, it behaves like
8609 `odd-page'; but for values greater than 1, it'll print
8610 only the odd sheet of paper.
8611
8612 Any other value is treated as nil.
8613
8614 If you set `ps-selected-pages' (see there for documentation), pages
8615 are filtered by `ps-selected-pages', and then by
8616 `ps-even-or-odd-pages'. For example, if we have:
8617
8618 (setq ps-selected-pages '(1 4 (6 . 10) (12 . 16) 20))
8619
8620 and we combine this with `ps-even-or-odd-pages' and
8621 `ps-n-up-printing', we get:
8622
8623 `ps-n-up-printing' = 1:
8624 `ps-even-or-odd-pages' PAGES PRINTED
8625 nil 1, 4, 6, 7, 8, 9, 10, 12, 13, 14, 15, 16, 20
8626 even-page 4, 6, 8, 10, 12, 14, 16, 20
8627 odd-page 1, 7, 9, 13, 15
8628 even-sheet 4, 6, 8, 10, 12, 14, 16, 20
8629 odd-sheet 1, 7, 9, 13, 15
8630
8631 `ps-n-up-printing' = 2:
8632 `ps-even-or-odd-pages' PAGES PRINTED
8633 nil 1/4, 6/7, 8/9, 10/12, 13/14, 15/16, 20
8634 even-page 4/6, 8/10, 12/14, 16/20
8635 odd-page 1/7, 9/13, 15
8636 even-sheet 6/7, 10/12, 15/16
8637 odd-sheet 1/4, 8/9, 13/14, 20
8638
8639 *** Miscellany (subgroup)
8640
8641 The variable `ps-error-handler-message' specifies where error handler
8642 messages should be sent.
8643
8644 It is also possible to add a user-defined PostScript prologue code in
8645 front of all generated prologue code by setting the variable
8646 `ps-user-defined-prologue'.
8647
8648 The variable `ps-line-number-font' specifies the font for line numbers.
8649
8650 The variable `ps-line-number-font-size' specifies the font size in
8651 points for line numbers.
8652
8653 The variable `ps-line-number-color' specifies the color for line
8654 numbers. See `ps-zebra-color' for documentation.
8655
8656 The variable `ps-line-number-step' specifies the interval in which
8657 line numbers are printed. For example, if `ps-line-number-step' is set
8658 to 2, the printing will look like:
8659
8660 1 one line
8661 one line
8662 3 one line
8663 one line
8664 5 one line
8665 one line
8666 ...
8667
8668 Valid values are:
8669
8670 integer an integer specifying the interval in which line numbers are
8671 printed. If it's smaller than or equal to zero, 1
8672 is used.
8673
8674 `zebra' specifies that only the line number of the first line in a
8675 zebra stripe is to be printed.
8676
8677 Any other value is treated as `zebra'.
8678
8679 The variable `ps-line-number-start' specifies the starting point in
8680 the interval given by `ps-line-number-step'. For example, if
8681 `ps-line-number-step' is set to 3, and `ps-line-number-start' is set to
8682 3, the output will look like:
8683
8684 one line
8685 one line
8686 3 one line
8687 one line
8688 one line
8689 6 one line
8690 one line
8691 one line
8692 9 one line
8693 one line
8694 ...
8695
8696 The variable `ps-postscript-code-directory' specifies the directory
8697 where the PostScript prologue file used by ps-print is found.
8698
8699 The variable `ps-line-spacing' determines the line spacing in points,
8700 for ordinary text, when generating PostScript (similar to
8701 `ps-font-size').
8702
8703 The variable `ps-paragraph-spacing' determines the paragraph spacing,
8704 in points, for ordinary text, when generating PostScript (similar to
8705 `ps-font-size').
8706
8707 The variable `ps-paragraph-regexp' specifies the paragraph delimiter.
8708
8709 The variable `ps-begin-cut-regexp' and `ps-end-cut-regexp' specify the
8710 start and end of a region to cut out when printing.
8711
8712 ** hideshow changes.
8713
8714 *** now supports hiding of blocks of single line comments (like // for
8715 C++, ; for lisp).
8716
8717 *** Support for java-mode added.
8718
8719 *** When doing `hs-hide-all' it is now possible to also hide the comments
8720 in the file if `hs-hide-comments-when-hiding-all' is set.
8721
8722 *** The new function `hs-hide-initial-comment' hides the comments at
8723 the beginning of the files. Finally those huge RCS logs don't stay in your
8724 way! This is run by default when entering the `hs-minor-mode'.
8725
8726 *** Now uses overlays instead of `selective-display', so is more
8727 robust and a lot faster.
8728
8729 *** A block beginning can span multiple lines.
8730
8731 *** The new variable `hs-show-hidden-short-form' if t, directs hideshow
8732 to show only the beginning of a block when it is hidden. See the
8733 documentation for more details.
8734
8735 ** Changes in Enriched mode.
8736
8737 *** When you visit a file in enriched-mode, Emacs will make sure it is
8738 filled to the current fill-column. This behavior is now independent
8739 of the size of the window. When you save the file, the fill-column in
8740 use is stored as well, so that the whole buffer need not be refilled
8741 the next time unless the fill-column is different.
8742
8743 *** use-hard-newlines is now a minor mode. When it is enabled, Emacs
8744 distinguishes between hard and soft newlines, and treats hard newlines
8745 as paragraph boundaries. Otherwise all newlines inserted are marked
8746 as soft, and paragraph boundaries are determined solely from the text.
8747
8748 ** Font Lock mode
8749
8750 *** Custom support
8751
8752 The variables font-lock-face-attributes, font-lock-display-type and
8753 font-lock-background-mode are now obsolete; the recommended way to specify the
8754 faces to use for Font Lock mode is with M-x customize-group on the new custom
8755 group font-lock-highlighting-faces. If you set font-lock-face-attributes in
8756 your ~/.emacs file, Font Lock mode will respect its value. However, you should
8757 consider converting from setting that variable to using M-x customize.
8758
8759 You can still use X resources to specify Font Lock face appearances.
8760
8761 *** Maximum decoration
8762
8763 Fontification now uses the maximum level of decoration supported by
8764 default. Previously, fontification used a mode-specific default level
8765 of decoration, which is typically the minimum level of decoration
8766 supported. You can set font-lock-maximum-decoration to nil
8767 to get the old behavior.
8768
8769 *** New support
8770
8771 Support is now provided for Java, Objective-C, AWK and SIMULA modes.
8772
8773 Note that Font Lock mode can be turned on without knowing exactly what modes
8774 support Font Lock mode, via the command global-font-lock-mode.
8775
8776 *** Configurable support
8777
8778 Support for C, C++, Objective-C and Java can be more easily configured for
8779 additional types and classes via the new variables c-font-lock-extra-types,
8780 c++-font-lock-extra-types, objc-font-lock-extra-types and, you guessed it,
8781 java-font-lock-extra-types. These value of each of these variables should be a
8782 list of regexps matching the extra type names. For example, the default value
8783 of c-font-lock-extra-types is ("\\sw+_t") which means fontification follows the
8784 convention that C type names end in _t. This results in slower fontification.
8785
8786 Of course, you can change the variables that specify fontification in whatever
8787 way you wish, typically by adding regexps. However, these new variables make
8788 it easier to make specific and common changes for the fontification of types.
8789
8790 *** Adding highlighting patterns to existing support
8791
8792 You can use the new function font-lock-add-keywords to add your own
8793 highlighting patterns, such as for project-local or user-specific constructs,
8794 for any mode.
8795
8796 For example, to highlight `FIXME:' words in C comments, put:
8797
8798 (font-lock-add-keywords 'c-mode '(("\\<FIXME:" 0 font-lock-warning-face t)))
8799
8800 in your ~/.emacs.
8801
8802 *** New faces
8803
8804 Font Lock now defines two new faces, font-lock-builtin-face and
8805 font-lock-warning-face. These are intended to highlight builtin keywords,
8806 distinct from a language's normal keywords, and objects that should be brought
8807 to user attention, respectively. Various modes now use these new faces.
8808
8809 *** Changes to fast-lock support mode
8810
8811 The fast-lock package, one of the two Font Lock support modes, can now process
8812 cache files silently. You can use the new variable fast-lock-verbose, in the
8813 same way as font-lock-verbose, to control this feature.
8814
8815 *** Changes to lazy-lock support mode
8816
8817 The lazy-lock package, one of the two Font Lock support modes, can now fontify
8818 according to the true syntactic context relative to other lines. You can use
8819 the new variable lazy-lock-defer-contextually to control this feature. If
8820 non-nil, changes to the buffer will cause subsequent lines in the buffer to be
8821 refontified after lazy-lock-defer-time seconds of idle time. If nil, then only
8822 the modified lines will be refontified; this is the same as the previous Lazy
8823 Lock mode behaviour and the behaviour of Font Lock mode.
8824
8825 This feature is useful in modes where strings or comments can span lines.
8826 For example, if a string or comment terminating character is deleted, then if
8827 this feature is enabled subsequent lines in the buffer will be correctly
8828 refontified to reflect their new syntactic context. Previously, only the line
8829 containing the deleted character would be refontified and you would have to use
8830 the command M-g M-g (font-lock-fontify-block) to refontify some lines.
8831
8832 As a consequence of this new feature, two other variables have changed:
8833
8834 Variable `lazy-lock-defer-driven' is renamed `lazy-lock-defer-on-scrolling'.
8835 Variable `lazy-lock-defer-time' can now only be a time, i.e., a number.
8836 Buffer modes for which on-the-fly deferral applies can be specified via the
8837 new variable `lazy-lock-defer-on-the-fly'.
8838
8839 If you set these variables in your ~/.emacs, then you may have to change those
8840 settings.
8841
8842 ** Ada mode changes.
8843
8844 *** There is now better support for using find-file.el with Ada mode.
8845 If you switch between spec and body, the cursor stays in the same
8846 procedure (modulo overloading). If a spec has no body file yet, but
8847 you try to switch to its body file, Ada mode now generates procedure
8848 stubs.
8849
8850 *** There are two new commands:
8851 - `ada-make-local' : invokes gnatmake on the current buffer
8852 - `ada-check-syntax' : check syntax of current buffer.
8853
8854 The user options `ada-compiler-make', `ada-make-options',
8855 `ada-language-version', `ada-compiler-syntax-check', and
8856 `ada-compile-options' are used within these commands.
8857
8858 *** Ada mode can now work with Outline minor mode. The outline level
8859 is calculated from the indenting, not from syntactic constructs.
8860 Outlining does not work if your code is not correctly indented.
8861
8862 *** The new function `ada-gnat-style' converts the buffer to the style of
8863 formatting used in GNAT. It places two blanks after a comment start,
8864 places one blank between a word end and an opening '(', and puts one
8865 space between a comma and the beginning of a word.
8866
8867 ** Scheme mode changes.
8868
8869 *** Scheme mode indentation now uses many of the facilities of Lisp
8870 mode; therefore, the variables to customize it are the variables used
8871 for Lisp mode which have names starting with `lisp-'. The variables
8872 with names starting with `scheme-' which used to do this no longer
8873 have any effect.
8874
8875 If you want to use different indentation for Scheme and Lisp, this is
8876 still possible, but now you must do it by adding a hook to
8877 scheme-mode-hook, which could work by setting the `lisp-' indentation
8878 variables as buffer-local variables.
8879
8880 *** DSSSL mode is a variant of Scheme mode, for editing DSSSL scripts.
8881 Use M-x dsssl-mode.
8882
8883 ** Changes to the emacsclient program
8884
8885 *** If a socket can't be found, and environment variables LOGNAME or
8886 USER are set, emacsclient now looks for a socket based on the UID
8887 associated with the name. That is an emacsclient running as root
8888 can connect to an Emacs server started by a non-root user.
8889
8890 *** The emacsclient program now accepts an option --no-wait which tells
8891 it to return immediately without waiting for you to "finish" the
8892 buffer in Emacs.
8893
8894 *** The new option --alternate-editor allows to specify an editor to
8895 use if Emacs is not running. The environment variable
8896 ALTERNATE_EDITOR can be used for the same effect; the command line
8897 option takes precedence.
8898
8899 ** M-x eldoc-mode enables a minor mode in which the echo area
8900 constantly shows the parameter list for function being called at point
8901 (in Emacs Lisp and Lisp Interaction modes only).
8902
8903 ** C-x n d now runs the new command narrow-to-defun,
8904 which narrows the accessible parts of the buffer to just
8905 the current defun.
8906
8907 ** Emacs now handles the `--' argument in the standard way; all
8908 following arguments are treated as ordinary file names.
8909
8910 ** On MSDOS and Windows, the bookmark file is now called _emacs.bmk,
8911 and the saved desktop file is now called _emacs.desktop (truncated if
8912 necessary).
8913
8914 ** When you kill a buffer that visits a file,
8915 if there are any registers that save positions in the file,
8916 these register values no longer become completely useless.
8917 If you try to go to such a register with C-x j, then you are
8918 asked whether to visit the file again. If you say yes,
8919 it visits the file and then goes to the same position.
8920
8921 ** When you visit a file that changes frequently outside Emacs--for
8922 example, a log of output from a process that continues to run--it may
8923 be useful for Emacs to revert the file without querying you whenever
8924 you visit the file afresh with C-x C-f.
8925
8926 You can request this behavior for certain files by setting the
8927 variable revert-without-query to a list of regular expressions. If a
8928 file's name matches any of these regular expressions, find-file and
8929 revert-buffer revert the buffer without asking for permission--but
8930 only if you have not edited the buffer text yourself.
8931
8932 ** set-default-font has been renamed to set-frame-font
8933 since it applies only to the current frame.
8934
8935 ** In TeX mode, you can use the variable tex-main-file to specify the
8936 file for tex-file to run TeX on. (By default, tex-main-file is nil,
8937 and tex-file runs TeX on the current visited file.)
8938
8939 This is useful when you are editing a document that consists of
8940 multiple files. In each of the included files, you can set up a local
8941 variable list which specifies the top-level file of your document for
8942 tex-main-file. Then tex-file will run TeX on the whole document
8943 instead of just the file you are editing.
8944
8945 ** RefTeX mode
8946
8947 RefTeX mode is a new minor mode with special support for \label, \ref
8948 and \cite macros in LaTeX documents. RefTeX distinguishes labels of
8949 different environments (equation, figure, ...) and has full support for
8950 multifile documents. To use it, select a buffer with a LaTeX document and
8951 turn the mode on with M-x reftex-mode. Here are the main user commands:
8952
8953 C-c ( reftex-label
8954 Creates a label semi-automatically. RefTeX is context sensitive and
8955 knows which kind of label is needed.
8956
8957 C-c ) reftex-reference
8958 Offers in a menu all labels in the document, along with context of the
8959 label definition. The selected label is referenced as \ref{LABEL}.
8960
8961 C-c [ reftex-citation
8962 Prompts for a regular expression and displays a list of matching BibTeX
8963 database entries. The selected entry is cited with a \cite{KEY} macro.
8964
8965 C-c & reftex-view-crossref
8966 Views the cross reference of a \ref or \cite command near point.
8967
8968 C-c = reftex-toc
8969 Shows a table of contents of the (multifile) document. From there you
8970 can quickly jump to every section.
8971
8972 Under X, RefTeX installs a "Ref" menu in the menu bar, with additional
8973 commands. Press `?' to get help when a prompt mentions this feature.
8974 Full documentation and customization examples are in the file
8975 reftex.el. You can use the finder to view the file documentation:
8976 C-h p --> tex --> reftex.el
8977
8978 ** Changes in BibTeX mode.
8979
8980 *** Info documentation is now available.
8981
8982 *** Don't allow parentheses in string constants anymore. This confused
8983 both the BibTeX program and Emacs BibTeX mode.
8984
8985 *** Renamed variable bibtex-mode-user-optional-fields to
8986 bibtex-user-optional-fields.
8987
8988 *** Removed variable bibtex-include-OPTannote
8989 (use bibtex-user-optional-fields instead).
8990
8991 *** New interactive functions to copy and kill fields and complete
8992 entries to the BibTeX kill ring, from where they can be yanked back by
8993 appropriate functions.
8994
8995 *** New interactive functions for repositioning and marking of
8996 entries. They are bound by default to C-M-l and C-M-h.
8997
8998 *** New hook bibtex-clean-entry-hook. It is called after entry has
8999 been cleaned.
9000
9001 *** New variable bibtex-field-delimiters, which replaces variables
9002 bibtex-field-{left|right}-delimiter.
9003
9004 *** New variable bibtex-entry-delimiters to determine how entries
9005 shall be delimited.
9006
9007 *** Allow preinitialization of fields. See documentation of
9008 bibtex-user-optional-fields, bibtex-entry-field-alist, and
9009 bibtex-include-OPTkey for details.
9010
9011 *** Book and InBook entries require either an author or an editor
9012 field. This is now supported by bibtex.el. Alternative fields are
9013 prefixed with `ALT'.
9014
9015 *** New variable bibtex-entry-format, which replaces variable
9016 bibtex-clean-entry-zap-empty-opts and allows specification of many
9017 formatting options performed on cleaning an entry (see variable
9018 documentation).
9019
9020 *** Even more control on how automatic keys are generated. See
9021 documentation of bibtex-generate-autokey for details. Transcriptions
9022 for foreign languages other than German are now handled, too.
9023
9024 *** New boolean user option bibtex-comma-after-last-field to decide if
9025 comma should be inserted at end of last field.
9026
9027 *** New boolean user option bibtex-align-at-equal-sign to determine if
9028 alignment should be made at left side of field contents or at equal
9029 signs. New user options to control entry layout (e.g. indentation).
9030
9031 *** New function bibtex-fill-entry to realign entries.
9032
9033 *** New function bibtex-reformat to reformat region or buffer.
9034
9035 *** New function bibtex-convert-alien to convert a BibTeX database
9036 from alien sources.
9037
9038 *** New function bibtex-complete-key (similar to bibtex-complete-string)
9039 to complete prefix to a key defined in buffer. Mainly useful in
9040 crossref entries.
9041
9042 *** New function bibtex-count-entries to count entries in buffer or
9043 region.
9044
9045 *** Added support for imenu.
9046
9047 *** The function `bibtex-validate' now checks current region instead
9048 of buffer if mark is active. Now it shows all errors of buffer in a
9049 `compilation mode' buffer. You can use the normal commands (e.g.
9050 `next-error') for compilation modes to jump to errors.
9051
9052 *** New variable `bibtex-string-file-path' to determine where the files
9053 from `bibtex-string-files' are searched.
9054
9055 ** Iso Accents mode now supports Latin-3 as an alternative.
9056
9057 ** The command next-error now opens blocks hidden by hideshow.
9058
9059 ** The function using-unix-filesystems has been replaced by the
9060 functions add-untranslated-filesystem and remove-untranslated-filesystem.
9061 Each of these functions takes the name of a drive letter or directory
9062 as an argument.
9063
9064 When a filesystem is added as untranslated, all files on it are read
9065 and written in binary mode (no cr/lf translation is performed).
9066
9067 ** browse-url changes
9068
9069 *** New methods for: Grail (browse-url-generic), MMM (browse-url-mmm),
9070 Lynx in a separate xterm (browse-url-lynx-xterm) or in an Emacs window
9071 (browse-url-lynx-emacs), remote W3 (browse-url-w3-gnudoit), generic
9072 non-remote-controlled browsers (browse-url-generic) and associated
9073 customization variables.
9074
9075 *** New commands `browse-url-of-region' and `browse-url'.
9076
9077 *** URLs marked up with <URL:...> (RFC1738) work if broken across
9078 lines. Browsing methods can be associated with URL regexps
9079 (e.g. mailto: URLs) via `browse-url-browser-function'.
9080
9081 ** Changes in Ediff
9082
9083 *** Clicking Mouse-2 on a brief command description in Ediff control panel
9084 pops up the Info file for this command.
9085
9086 *** There is now a variable, ediff-autostore-merges, which controls whether
9087 the result of a merge is saved in a file. By default, this is done only when
9088 merge is done from a session group (eg, when merging files in two different
9089 directories).
9090
9091 *** Since Emacs 19.31 (this hasn't been announced before), Ediff can compare
9092 and merge groups of files residing in different directories, or revisions of
9093 files in the same directory.
9094
9095 *** Since Emacs 19.31, Ediff can apply multi-file patches interactively.
9096 The patches must be in the context format or GNU unified format. (The bug
9097 related to the GNU format has now been fixed.)
9098
9099 ** Changes in Viper
9100
9101 *** The startup file is now .viper instead of .vip
9102 *** All variable/function names have been changed to start with viper-
9103 instead of vip-.
9104 *** C-\ now simulates the meta-key in all Viper states.
9105 *** C-z in Insert state now escapes to Vi for the duration of the next
9106 Viper command. In Vi and Insert states, C-z behaves as before.
9107 *** C-c \ escapes to Vi for one command if Viper is in Insert or Emacs states.
9108 *** _ is no longer the meta-key in Vi state.
9109 *** The variable viper-insert-state-cursor-color can be used to change cursor
9110 color when Viper is in insert state.
9111 *** If search lands the cursor near the top or the bottom of the window,
9112 Viper pulls the window up or down to expose more context. The variable
9113 viper-adjust-window-after-search controls this behavior.
9114
9115 ** Etags changes.
9116
9117 *** In C, C++, Objective C and Java, Etags tags global variables by
9118 default. The resulting tags files are inflated by 30% on average.
9119 Use --no-globals to turn this feature off. Etags can also tag
9120 variables which are members of structure-like constructs, but it does
9121 not by default. Use --members to turn this feature on.
9122
9123 *** C++ member functions are now recognized as tags.
9124
9125 *** Java is tagged like C++. In addition, "extends" and "implements"
9126 constructs are tagged. Files are recognised by the extension .java.
9127
9128 *** Etags can now handle programs written in Postscript. Files are
9129 recognised by the extensions .ps and .pdb (Postscript with C syntax).
9130 In Postscript, tags are lines that start with a slash.
9131
9132 *** Etags now handles Objective C and Objective C++ code. The usual C and
9133 C++ tags are recognized in these languages; in addition, etags
9134 recognizes special Objective C syntax for classes, class categories,
9135 methods and protocols.
9136
9137 *** Etags also handles Cobol. Files are recognised by the extension
9138 .cobol. The tagged lines are those containing a word that begins in
9139 column 8 and ends in a full stop, i.e. anything that could be a
9140 paragraph name.
9141
9142 *** Regexps in Etags now support intervals, as in ed or grep. The syntax of
9143 an interval is \{M,N\}, and it means to match the preceding expression
9144 at least M times and as many as N times.
9145
9146 ** The format for specifying a custom format for time-stamp to insert
9147 in files has changed slightly.
9148
9149 With the new enhancements to the functionality of format-time-string,
9150 time-stamp-format will change to be eventually compatible with it.
9151 This conversion is being done in two steps to maintain compatibility
9152 with old time-stamp-format values.
9153
9154 In the new scheme, alternate case is signified by the number-sign
9155 (`#') modifier, rather than changing the case of the format character.
9156 This feature is as yet incompletely implemented for compatibility
9157 reasons.
9158
9159 In the old time-stamp-format, all numeric fields defaulted to their
9160 natural width. (With format-time-string, each format has a
9161 fixed-width default.) In this version, you can specify the colon
9162 (`:') modifier to a numeric conversion to mean "give me the historical
9163 time-stamp-format width default." Do not use colon if you are
9164 specifying an explicit width, as in "%02d".
9165
9166 Numbers are no longer truncated to the requested width, except in the
9167 case of "%02y", which continues to give a two-digit year. Digit
9168 truncation probably wasn't being used for anything else anyway.
9169
9170 The new formats will work with old versions of Emacs. New formats are
9171 being recommended now to allow time-stamp-format to change in the
9172 future to be compatible with format-time-string. The new forms being
9173 recommended now will continue to work then.
9174
9175 See the documentation string for the variable time-stamp-format for
9176 details.
9177
9178 ** There are some additional major modes:
9179
9180 dcl-mode, for editing VMS DCL files.
9181 m4-mode, for editing files of m4 input.
9182 meta-mode, for editing MetaFont and MetaPost source files.
9183
9184 ** In Shell mode, the command shell-copy-environment-variable lets you
9185 copy the value of a specified environment variable from the subshell
9186 into Emacs.
9187
9188 ** New Lisp packages include:
9189
9190 *** battery.el displays battery status for laptops.
9191
9192 *** M-x bruce (named after Lenny Bruce) is a program that might
9193 be used for adding some indecent words to your email.
9194
9195 *** M-x crisp-mode enables an emulation for the CRiSP editor.
9196
9197 *** M-x dirtrack arranges for better tracking of directory changes
9198 in shell buffers.
9199
9200 *** The new library elint.el provides for linting of Emacs Lisp code.
9201 See the documentation for `elint-initialize', `elint-current-buffer'
9202 and `elint-defun'.
9203
9204 *** M-x expand-add-abbrevs defines a special kind of abbrev which is
9205 meant for programming constructs. These abbrevs expand like ordinary
9206 ones, when you type SPC, but only at the end of a line and not within
9207 strings or comments.
9208
9209 These abbrevs can act as templates: you can define places within an
9210 abbrev for insertion of additional text. Once you expand the abbrev,
9211 you can then use C-x a p and C-x a n to move back and forth to these
9212 insertion points. Thus you can conveniently insert additional text
9213 at these points.
9214
9215 *** filecache.el remembers the location of files so that you
9216 can visit them by short forms of their names.
9217
9218 *** find-func.el lets you find the definition of the user-loaded
9219 Emacs Lisp function at point.
9220
9221 *** M-x handwrite converts text to a "handwritten" picture.
9222
9223 *** M-x iswitchb-buffer is a command for switching to a buffer, much like
9224 switch-buffer, but it reads the argument in a more helpful way.
9225
9226 *** M-x landmark implements a neural network for landmark learning.
9227
9228 *** M-x locate provides a convenient interface to the `locate' program.
9229
9230 *** M4 mode is a new mode for editing files of m4 input.
9231
9232 *** mantemp.el creates C++ manual template instantiations
9233 from the GCC error messages which indicate which instantiations are needed.
9234
9235 *** mouse-copy.el provides a one-click copy and move feature.
9236 You can drag a region with M-mouse-1, and it is automatically
9237 inserted at point. M-Shift-mouse-1 deletes the text from its
9238 original place after inserting the copy.
9239
9240 *** mouse-drag.el lets you do scrolling by dragging Mouse-2
9241 on the buffer.
9242
9243 You click the mouse and move; that distance either translates into the
9244 velocity to scroll (with mouse-drag-throw) or the distance to scroll
9245 (with mouse-drag-drag). Horizontal scrolling is enabled when needed.
9246
9247 Enable mouse-drag with:
9248 (global-set-key [down-mouse-2] 'mouse-drag-throw)
9249 -or-
9250 (global-set-key [down-mouse-2] 'mouse-drag-drag)
9251
9252 *** mspools.el is useful for determining which mail folders have
9253 mail waiting to be read in them. It works with procmail.
9254
9255 *** Octave mode is a major mode for editing files of input for Octave.
9256 It comes with a facility for communicating with an Octave subprocess.
9257
9258 *** ogonek
9259
9260 The ogonek package provides functions for changing the coding of
9261 Polish diacritic characters in buffers. Codings known from various
9262 platforms are supported such as ISO8859-2, Mazovia, IBM Latin2, and
9263 TeX. For example, you can change the coding from Mazovia to
9264 ISO8859-2. Another example is a change of coding from ISO8859-2 to
9265 prefix notation (in which `/a' stands for the aogonek character, for
9266 instance) and vice versa.
9267
9268 To use this package load it using
9269 M-x load-library [enter] ogonek
9270 Then, you may get an explanation by calling one of
9271 M-x ogonek-jak -- in Polish
9272 M-x ogonek-how -- in English
9273 The info specifies the commands and variables provided as well as the
9274 ways of customization in `.emacs'.
9275
9276 *** Interface to ph.
9277
9278 Emacs provides a client interface to CCSO Nameservers (ph/qi)
9279
9280 The CCSO nameserver is used in many universities to provide directory
9281 services about people. ph.el provides a convenient Emacs interface to
9282 these servers.
9283
9284 *** uce.el is useful for replying to unsolicited commercial email.
9285
9286 *** vcursor.el implements a "virtual cursor" feature.
9287 You can move the virtual cursor with special commands
9288 while the real cursor does not move.
9289
9290 *** webjump.el is a "hot list" package which you can set up
9291 for visiting your favorite web sites.
9292
9293 *** M-x winner-mode is a minor mode which saves window configurations,
9294 so you can move back to other configurations that you have recently used.
9295
9296 ** movemail change
9297
9298 Movemail no longer needs to be installed setuid root in order for POP
9299 mail retrieval to function properly. This is because it no longer
9300 supports the RPOP (reserved-port POP) protocol; instead, it uses the
9301 user's POP password to authenticate to the mail server.
9302
9303 This change was made earlier, but not reported in NEWS before.
9304 \f
9305 * Emacs 20.1 changes for MS-DOS and MS-Windows.
9306
9307 ** Changes in handling MS-DOS/MS-Windows text files.
9308
9309 Emacs handles three different conventions for representing
9310 end-of-line: CRLF for MSDOS, LF for Unix and GNU, and CR (used on the
9311 Macintosh). Emacs determines which convention is used in a specific
9312 file based on the contents of that file (except for certain special
9313 file names), and when it saves the file, it uses the same convention.
9314
9315 To save the file and change the end-of-line convention, you can use
9316 C-x RET f (set-buffer-file-coding-system) to specify a different
9317 coding system for the buffer. Then, when you save the file, the newly
9318 specified coding system will take effect. For example, to save with
9319 LF, specify undecided-unix (or some other ...-unix coding system); to
9320 save with CRLF, specify undecided-dos.
9321 \f
9322 * Lisp Changes in Emacs 20.1
9323
9324 ** Byte-compiled files made with Emacs 20 will, in general, work in
9325 Emacs 19 as well, as long as the source code runs in Emacs 19. And
9326 vice versa: byte-compiled files made with Emacs 19 should also run in
9327 Emacs 20, as long as the program itself works in Emacs 20.
9328
9329 ** Windows-specific functions and variables have been renamed
9330 to start with w32- instead of win32-.
9331
9332 In hacker language, calling something a "win" is a form of praise. We
9333 don't want to praise a non-free Microsoft system, so we don't call it
9334 "win".
9335
9336 ** Basic Lisp changes
9337
9338 *** A symbol whose name starts with a colon now automatically
9339 evaluates to itself. Therefore such a symbol can be used as a constant.
9340
9341 *** The defined purpose of `defconst' has been changed. It should now
9342 be used only for values that should not be changed whether by a program
9343 or by the user.
9344
9345 The actual behavior of defconst has not been changed.
9346
9347 *** There are new macros `when' and `unless'
9348
9349 (when CONDITION BODY...) is short for (if CONDITION (progn BODY...))
9350 (unless CONDITION BODY...) is short for (if CONDITION nil BODY...)
9351
9352 *** Emacs now defines functions caar, cadr, cdar and cddr with their
9353 usual Lisp meanings. For example, caar returns the car of the car of
9354 its argument.
9355
9356 *** equal, when comparing strings, now ignores their text properties.
9357
9358 *** The new function `functionp' tests whether an object is a function.
9359
9360 *** arrayp now returns t for char-tables and bool-vectors.
9361
9362 *** Certain primitives which use characters (as integers) now get an
9363 error if the integer is not a valid character code. These primitives
9364 include insert-char, char-to-string, and the %c construct in the
9365 `format' function.
9366
9367 *** The `require' function now insists on adding a suffix, either .el
9368 or .elc, to the file name. Thus, (require 'foo) will not use a file
9369 whose name is just foo. It insists on foo.el or foo.elc.
9370
9371 *** The `autoload' function, when the file name does not contain
9372 either a directory name or the suffix .el or .elc, insists on
9373 adding one of these suffixes.
9374
9375 *** string-to-number now takes an optional second argument BASE
9376 which specifies the base to use when converting an integer.
9377 If BASE is omitted, base 10 is used.
9378
9379 We have not implemented other radices for floating point numbers,
9380 because that would be much more work and does not seem useful.
9381
9382 *** substring now handles vectors as well as strings.
9383
9384 *** The Common Lisp function eql is no longer defined normally.
9385 You must load the `cl' library to define it.
9386
9387 *** The new macro `with-current-buffer' lets you evaluate an expression
9388 conveniently with a different current buffer. It looks like this:
9389
9390 (with-current-buffer BUFFER BODY-FORMS...)
9391
9392 BUFFER is the expression that says which buffer to use.
9393 BODY-FORMS say what to do in that buffer.
9394
9395 *** The new primitive `save-current-buffer' saves and restores the
9396 choice of current buffer, like `save-excursion', but without saving or
9397 restoring the value of point or the mark. `with-current-buffer'
9398 works using `save-current-buffer'.
9399
9400 *** The new macro `with-temp-file' lets you do some work in a new buffer and
9401 write the output to a specified file. Like `progn', it returns the value
9402 of the last form.
9403
9404 *** The new macro `with-temp-buffer' lets you do some work in a new buffer,
9405 which is discarded after use. Like `progn', it returns the value of the
9406 last form. If you wish to return the buffer contents, use (buffer-string)
9407 as the last form.
9408
9409 *** The new function split-string takes a string, splits it at certain
9410 characters, and returns a list of the substrings in between the
9411 matches.
9412
9413 For example, (split-string "foo bar lose" " +") returns ("foo" "bar" "lose").
9414
9415 *** The new macro with-output-to-string executes some Lisp expressions
9416 with standard-output set up so that all output feeds into a string.
9417 Then it returns that string.
9418
9419 For example, if the current buffer name is `foo',
9420
9421 (with-output-to-string
9422 (princ "The buffer is ")
9423 (princ (buffer-name)))
9424
9425 returns "The buffer is foo".
9426
9427 ** Non-ASCII characters are now supported, if enable-multibyte-characters
9428 is non-nil.
9429
9430 These characters have character codes above 256. When inserted in the
9431 buffer or stored in a string, they are represented as multibyte
9432 characters that occupy several buffer positions each.
9433
9434 *** When enable-multibyte-characters is non-nil, a single character in
9435 a buffer or string can be two or more bytes (as many as four).
9436
9437 Buffers and strings are still made up of unibyte elements;
9438 character positions and string indices are always measured in bytes.
9439 Therefore, moving forward one character can increase the buffer
9440 position by 2, 3 or 4. The function forward-char moves by whole
9441 characters, and therefore is no longer equivalent to
9442 (lambda (n) (goto-char (+ (point) n))).
9443
9444 ASCII characters (codes 0 through 127) are still single bytes, always.
9445 Sequences of byte values 128 through 255 are used to represent
9446 non-ASCII characters. These sequences are called "multibyte
9447 characters".
9448
9449 The first byte of a multibyte character is always in the range 128
9450 through 159 (octal 0200 through 0237). These values are called
9451 "leading codes". The second and subsequent bytes are always in the
9452 range 160 through 255 (octal 0240 through 0377). The first byte, the
9453 leading code, determines how many bytes long the sequence is.
9454
9455 *** The function forward-char moves over characters, and therefore
9456 (forward-char 1) may increase point by more than 1 if it moves over a
9457 multibyte character. Likewise, delete-char always deletes a
9458 character, which may be more than one buffer position.
9459
9460 This means that some Lisp programs, which assume that a character is
9461 always one buffer position, need to be changed.
9462
9463 However, all ASCII characters are always one buffer position.
9464
9465 *** The regexp [\200-\377] no longer matches all non-ASCII characters,
9466 because when enable-multibyte-characters is non-nil, these characters
9467 have codes that are not in the range octal 200 to octal 377. However,
9468 the regexp [^\000-\177] does match all non-ASCII characters,
9469 guaranteed.
9470
9471 *** The function char-boundary-p returns non-nil if position POS is
9472 between two characters in the buffer (not in the middle of a
9473 character).
9474
9475 When the value is non-nil, it says what kind of character follows POS:
9476
9477 0 if POS is at an ASCII character or at the end of range,
9478 1 if POS is before a 2-byte length multi-byte form,
9479 2 if POS is at a head of 3-byte length multi-byte form,
9480 3 if POS is at a head of 4-byte length multi-byte form,
9481 4 if POS is at a head of multi-byte form of a composite character.
9482
9483 *** The function char-bytes returns how many bytes the character CHAR uses.
9484
9485 *** Strings can contain multibyte characters. The function
9486 `length' returns the string length counting bytes, which may be
9487 more than the number of characters.
9488
9489 You can include a multibyte character in a string constant by writing
9490 it literally. You can also represent it with a hex escape,
9491 \xNNNNNNN..., using as many digits as necessary. Any character which
9492 is not a valid hex digit terminates this construct. If you want to
9493 follow it with a character that is a hex digit, write backslash and
9494 newline in between; that will terminate the hex escape.
9495
9496 *** The function concat-chars takes arguments which are characters
9497 and returns a string containing those characters.
9498
9499 *** The function sref access a multibyte character in a string.
9500 (sref STRING INDX) returns the character in STRING at INDEX. INDEX
9501 counts from zero. If INDEX is at a position in the middle of a
9502 character, sref signals an error.
9503
9504 *** The function chars-in-string returns the number of characters
9505 in a string. This is less than the length of the string, if the
9506 string contains multibyte characters (the length counts bytes).
9507
9508 *** The function chars-in-region returns the number of characters
9509 in a region from BEG to END. This is less than (- END BEG) if the
9510 region contains multibyte characters (the length counts bytes).
9511
9512 *** The function string-to-list converts a string to a list of
9513 the characters in it. string-to-vector converts a string
9514 to a vector of the characters in it.
9515
9516 *** The function store-substring alters part of the contents
9517 of a string. You call it as follows:
9518
9519 (store-substring STRING IDX OBJ)
9520
9521 This says to alter STRING, by storing OBJ starting at index IDX in
9522 STRING. OBJ may be either a character or a (smaller) string.
9523 This function really does alter the contents of STRING.
9524 Since it is impossible to change the length of an existing string,
9525 it is an error if OBJ doesn't fit within STRING's actual length.
9526
9527 *** char-width returns the width (in columns) of the character CHAR,
9528 if it were displayed in the current buffer and the selected window.
9529
9530 *** string-width returns the width (in columns) of the text in STRING,
9531 if it were displayed in the current buffer and the selected window.
9532
9533 *** truncate-string-to-width shortens a string, if necessary,
9534 to fit within a certain number of columns. (Of course, it does
9535 not alter the string that you give it; it returns a new string
9536 which contains all or just part of the existing string.)
9537
9538 (truncate-string-to-width STR END-COLUMN &optional START-COLUMN PADDING)
9539
9540 This returns the part of STR up to column END-COLUMN.
9541
9542 The optional argument START-COLUMN specifies the starting column.
9543 If this is non-nil, then the first START-COLUMN columns of the string
9544 are not included in the resulting value.
9545
9546 The optional argument PADDING, if non-nil, is a padding character to be added
9547 at the beginning and end the resulting string, to extend it to exactly
9548 WIDTH columns. If PADDING is nil, that means do not pad; then, if STRING
9549 is narrower than WIDTH, the value is equal to STRING.
9550
9551 If PADDING and START-COLUMN are both non-nil, and if there is no clean
9552 place in STRING that corresponds to START-COLUMN (because one
9553 character extends across that column), then the padding character
9554 PADDING is added one or more times at the beginning of the result
9555 string, so that its columns line up as if it really did start at
9556 column START-COLUMN.
9557
9558 *** When the functions in the list after-change-functions are called,
9559 the third argument is the number of bytes in the pre-change text, not
9560 necessarily the number of characters. It is, in effect, the
9561 difference in buffer position between the beginning and the end of the
9562 changed text, before the change.
9563
9564 *** The characters Emacs uses are classified in various character
9565 sets, each of which has a name which is a symbol. In general there is
9566 one character set for each script, not for each language.
9567
9568 **** The function charsetp tests whether an object is a character set name.
9569
9570 **** The variable charset-list holds a list of character set names.
9571
9572 **** char-charset, given a character code, returns the name of the character
9573 set that the character belongs to. (The value is a symbol.)
9574
9575 **** split-char, given a character code, returns a list containing the
9576 name of the character set, followed by one or two byte-values
9577 which identify the character within that character set.
9578
9579 **** make-char, given a character set name and one or two subsequent
9580 byte-values, constructs a character code. This is roughly the
9581 opposite of split-char.
9582
9583 **** find-charset-region returns a list of the character sets
9584 of all the characters between BEG and END.
9585
9586 **** find-charset-string returns a list of the character sets
9587 of all the characters in a string.
9588
9589 *** Here are the Lisp facilities for working with coding systems
9590 and specifying coding systems.
9591
9592 **** The function coding-system-list returns a list of all coding
9593 system names (symbols). With optional argument t, it returns a list
9594 of all distinct base coding systems, not including variants.
9595 (Variant coding systems are those like latin-1-dos, latin-1-unix
9596 and latin-1-mac which specify the end-of-line conversion as well
9597 as what to do about code conversion.)
9598
9599 **** coding-system-p tests a symbol to see if it is a coding system
9600 name. It returns t if so, nil if not.
9601
9602 **** file-coding-system-alist specifies which coding systems to use
9603 for certain file names. It works like network-coding-system-alist,
9604 except that the PATTERN is matched against the file name.
9605
9606 Each element has the format (PATTERN . VAL), where PATTERN determines
9607 which file names the element applies to. PATTERN should be a regexp
9608 to match against a file name.
9609
9610 VAL is a coding system, a cons cell containing two coding systems, or
9611 a function symbol. If VAL is a coding system, it is used for both
9612 decoding what received from the network stream and encoding what sent
9613 to the network stream. If VAL is a cons cell containing two coding
9614 systems, the car specifies the coding system for decoding, and the cdr
9615 specifies the coding system for encoding.
9616
9617 If VAL is a function symbol, the function must return a coding system
9618 or a cons cell containing two coding systems, which is used as above.
9619
9620 **** The variable network-coding-system-alist specifies
9621 the coding system to use for network sockets.
9622
9623 Each element has the format (PATTERN . VAL), where PATTERN determines
9624 which network sockets the element applies to. PATTERN should be
9625 either a port number or a regular expression matching some network
9626 service names.
9627
9628 VAL is a coding system, a cons cell containing two coding systems, or
9629 a function symbol. If VAL is a coding system, it is used for both
9630 decoding what received from the network stream and encoding what sent
9631 to the network stream. If VAL is a cons cell containing two coding
9632 systems, the car specifies the coding system for decoding, and the cdr
9633 specifies the coding system for encoding.
9634
9635 If VAL is a function symbol, the function must return a coding system
9636 or a cons cell containing two coding systems, which is used as above.
9637
9638 **** process-coding-system-alist specifies which coding systems to use
9639 for certain subprocess. It works like network-coding-system-alist,
9640 except that the PATTERN is matched against the program name used to
9641 start the subprocess.
9642
9643 **** The variable default-process-coding-system specifies the coding
9644 systems to use for subprocess (and net connection) input and output,
9645 when nothing else specifies what to do. The value is a cons cell
9646 (OUTPUT-CODING . INPUT-CODING). OUTPUT-CODING applies to output
9647 to the subprocess, and INPUT-CODING applies to input from it.
9648
9649 **** The variable coding-system-for-write, if non-nil, specifies the
9650 coding system to use for writing a file, or for output to a synchronous
9651 subprocess.
9652
9653 It also applies to any asynchronous subprocess or network connection,
9654 but in a different way: the value of coding-system-for-write when you
9655 start the subprocess or connection affects that subprocess or
9656 connection permanently or until overridden.
9657
9658 The variable coding-system-for-write takes precedence over
9659 file-coding-system-alist, process-coding-system-alist and
9660 network-coding-system-alist, and all other methods of specifying a
9661 coding system for output. But most of the time this variable is nil.
9662 It exists so that Lisp programs can bind it to a specific coding
9663 system for one operation at a time.
9664
9665 **** coding-system-for-read applies similarly to input from
9666 files, subprocesses or network connections.
9667
9668 **** The function process-coding-system tells you what
9669 coding systems(s) an existing subprocess is using.
9670 The value is a cons cell,
9671 (DECODING-CODING-SYSTEM . ENCODING-CODING-SYSTEM)
9672 where DECODING-CODING-SYSTEM is used for decoding output from
9673 the subprocess, and ENCODING-CODING-SYSTEM is used for encoding
9674 input to the subprocess.
9675
9676 **** The function set-process-coding-system can be used to
9677 change the coding systems in use for an existing subprocess.
9678
9679 ** Emacs has a new facility to help users manage the many
9680 customization options. To make a Lisp program work with this facility,
9681 you need to use the new macros defgroup and defcustom.
9682
9683 You use defcustom instead of defvar, for defining a user option
9684 variable. The difference is that you specify two additional pieces of
9685 information (usually): the "type" which says what values are
9686 legitimate, and the "group" which specifies the hierarchy for
9687 customization.
9688
9689 Thus, instead of writing
9690
9691 (defvar foo-blurgoze nil
9692 "*Non-nil means that foo will act very blurgozely.")
9693
9694 you would now write this:
9695
9696 (defcustom foo-blurgoze nil
9697 "*Non-nil means that foo will act very blurgozely."
9698 :type 'boolean
9699 :group foo)
9700
9701 The type `boolean' means that this variable has only
9702 two meaningful states: nil and non-nil. Other type values
9703 describe other possibilities; see the manual for Custom
9704 for a description of them.
9705
9706 The "group" argument is used to specify a group which the option
9707 should belong to. You define a new group like this:
9708
9709 (defgroup ispell nil
9710 "Spell checking using Ispell."
9711 :group 'processes)
9712
9713 The "group" argument in defgroup specifies the parent group. The root
9714 group is called `emacs'; it should not contain any variables itself,
9715 but only other groups. The immediate subgroups of `emacs' correspond
9716 to the keywords used by C-h p. Under these subgroups come
9717 second-level subgroups that belong to individual packages.
9718
9719 Each Emacs package should have its own set of groups. A simple
9720 package should have just one group; a more complex package should
9721 have a hierarchy of its own groups. The sole or root group of a
9722 package should be a subgroup of one or more of the "keyword"
9723 first-level subgroups.
9724
9725 ** New `widget' library for inserting UI components in buffers.
9726
9727 This library, used by the new custom library, is documented in a
9728 separate manual that accompanies Emacs.
9729
9730 ** easy-mmode
9731
9732 The easy-mmode package provides macros and functions that make
9733 developing minor modes easier. Roughly, the programmer has to code
9734 only the functionality of the minor mode. All the rest--toggles,
9735 predicate, and documentation--can be done in one call to the macro
9736 `easy-mmode-define-minor-mode' (see the documentation). See also
9737 `easy-mmode-define-keymap'.
9738
9739 ** Text property changes
9740
9741 *** The `intangible' property now works on overlays as well as on a
9742 text property.
9743
9744 *** The new functions next-char-property-change and
9745 previous-char-property-change scan through the buffer looking for a
9746 place where either a text property or an overlay might change. The
9747 functions take two arguments, POSITION and LIMIT. POSITION is the
9748 starting position for the scan. LIMIT says where to stop the scan.
9749
9750 If no property change is found before LIMIT, the value is LIMIT. If
9751 LIMIT is nil, scan goes to the beginning or end of the accessible part
9752 of the buffer. If no property change is found, the value is the
9753 position of the beginning or end of the buffer.
9754
9755 *** In the `local-map' text property or overlay property, the property
9756 value can now be a symbol whose function definition is a keymap. This
9757 is an alternative to using the keymap itself.
9758
9759 ** Changes in invisibility features
9760
9761 *** Isearch can now temporarily show parts of the buffer which are
9762 hidden by an overlay with a invisible property, when the search match
9763 is inside that portion of the buffer. To enable this the overlay
9764 should have a isearch-open-invisible property which is a function that
9765 would be called having the overlay as an argument, the function should
9766 make the overlay visible.
9767
9768 During incremental search the overlays are shown by modifying the
9769 invisible and intangible properties, if beside this more actions are
9770 needed the overlay should have a isearch-open-invisible-temporary
9771 which is a function. The function is called with 2 arguments: one is
9772 the overlay and the second is nil when it should show the overlay and
9773 t when it should hide it.
9774
9775 *** add-to-invisibility-spec, remove-from-invisibility-spec
9776
9777 Modes that use overlays to hide portions of a buffer should set the
9778 invisible property of the overlay to the mode's name (or another symbol)
9779 and modify the `buffer-invisibility-spec' to include that symbol.
9780 Use `add-to-invisibility-spec' and `remove-from-invisibility-spec' to
9781 manipulate the `buffer-invisibility-spec'.
9782 Here is an example of how to do this:
9783
9784 ;; If we want to display an ellipsis:
9785 (add-to-invisibility-spec '(my-symbol . t))
9786 ;; If you don't want ellipsis:
9787 (add-to-invisibility-spec 'my-symbol)
9788
9789 ...
9790 (overlay-put (make-overlay beginning end) 'invisible 'my-symbol)
9791
9792 ...
9793 ;; When done with the overlays:
9794 (remove-from-invisibility-spec '(my-symbol . t))
9795 ;; Or respectively:
9796 (remove-from-invisibility-spec 'my-symbol)
9797
9798 ** Changes in syntax parsing.
9799
9800 *** The syntax-directed buffer-scan functions (such as
9801 `parse-partial-sexp', `forward-word' and similar functions) can now
9802 obey syntax information specified by text properties, if the variable
9803 `parse-sexp-lookup-properties' is non-nil.
9804
9805 If the value of `parse-sexp-lookup-properties' is nil, the behavior
9806 is as before: the syntax-table of the current buffer is always
9807 used to determine the syntax of the character at the position.
9808
9809 When `parse-sexp-lookup-properties' is non-nil, the syntax of a
9810 character in the buffer is calculated thus:
9811
9812 a) if the `syntax-table' text-property of that character
9813 is a cons, this cons becomes the syntax-type;
9814
9815 Valid values of `syntax-table' text-property are: nil, a valid
9816 syntax-table, and a valid syntax-table element, i.e.,
9817 a cons cell of the form (SYNTAX-CODE . MATCHING-CHAR).
9818
9819 b) if the character's `syntax-table' text-property
9820 is a syntax table, this syntax table is used
9821 (instead of the syntax-table of the current buffer) to
9822 determine the syntax type of the character.
9823
9824 c) otherwise the syntax-type is determined by the syntax-table
9825 of the current buffer.
9826
9827 *** The meaning of \s in regular expressions is also affected by the
9828 value of `parse-sexp-lookup-properties'. The details are the same as
9829 for the syntax-directed buffer-scan functions.
9830
9831 *** There are two new syntax-codes, `!' and `|' (numeric values 14
9832 and 15). A character with a code `!' starts a comment which is ended
9833 only by another character with the same code (unless quoted). A
9834 character with a code `|' starts a string which is ended only by
9835 another character with the same code (unless quoted).
9836
9837 These codes are mainly meant for use as values of the `syntax-table'
9838 text property.
9839
9840 *** The function `parse-partial-sexp' has new semantics for the sixth
9841 arg COMMENTSTOP. If it is `syntax-table', parse stops after the start
9842 of a comment or a string, or after end of a comment or a string.
9843
9844 *** The state-list which the return value from `parse-partial-sexp'
9845 (and can also be used as an argument) now has an optional ninth
9846 element: the character address of the start of last comment or string;
9847 nil if none. The fourth and eighth elements have special values if the
9848 string/comment is started by a "!" or "|" syntax-code.
9849
9850 *** Since new features of `parse-partial-sexp' allow a complete
9851 syntactic parsing, `font-lock' no longer supports
9852 `font-lock-comment-start-regexp'.
9853
9854 ** Changes in face features
9855
9856 *** The face functions are now unconditionally defined in Emacs, even
9857 if it does not support displaying on a device that supports faces.
9858
9859 *** The function face-documentation returns the documentation string
9860 of a face (or nil if it doesn't have one).
9861
9862 *** The function face-bold-p returns t if a face should be bold.
9863 set-face-bold-p sets that flag.
9864
9865 *** The function face-italic-p returns t if a face should be italic.
9866 set-face-italic-p sets that flag.
9867
9868 *** You can now specify foreground and background colors for text
9869 by adding elements of the form (foreground-color . COLOR-NAME)
9870 and (background-color . COLOR-NAME) to the list of faces in
9871 the `face' property (either the character's text property or an
9872 overlay property).
9873
9874 This means that you no longer need to create named faces to use
9875 arbitrary colors in a Lisp package.
9876
9877 ** Changes in file-handling functions
9878
9879 *** File-access primitive functions no longer discard an extra redundant
9880 directory name from the beginning of the file name. In other words,
9881 they no longer do anything special with // or /~. That conversion
9882 is now done only in substitute-in-file-name.
9883
9884 This makes it possible for a Lisp program to open a file whose name
9885 begins with ~.
9886
9887 *** If copy-file is unable to set the date of the output file,
9888 it now signals an error with the condition file-date-error.
9889
9890 *** The inode number returned by file-attributes may be an integer (if
9891 the number fits in a Lisp integer) or a list of integers.
9892
9893 *** insert-file-contents can now read from a special file,
9894 as long as the arguments VISIT and REPLACE are nil.
9895
9896 *** The RAWFILE arg to find-file-noselect, if non-nil, now suppresses
9897 character code conversion as well as other things.
9898
9899 Meanwhile, this feature does work with remote file names
9900 (formerly it did not).
9901
9902 *** Lisp packages which create temporary files should use the TMPDIR
9903 environment variable to decide which directory to put them in.
9904
9905 *** interpreter-mode-alist elements now specify regexps
9906 instead of constant strings.
9907
9908 *** expand-file-name no longer treats `//' or `/~' specially. It used
9909 to delete all the text of a file name up through the first slash of
9910 any `//' or `/~' sequence. Now it passes them straight through.
9911
9912 substitute-in-file-name continues to treat those sequences specially,
9913 in the same way as before.
9914
9915 *** The variable `format-alist' is more general now.
9916 The FROM-FN and TO-FN in a format definition can now be strings
9917 which specify shell commands to use as filters to perform conversion.
9918
9919 *** The new function access-file tries to open a file, and signals an
9920 error if that fails. If the open succeeds, access-file does nothing
9921 else, and returns nil.
9922
9923 *** The function insert-directory now signals an error if the specified
9924 directory cannot be listed.
9925
9926 ** Changes in minibuffer input
9927
9928 *** The functions read-buffer, read-variable, read-command, read-string
9929 read-file-name, read-from-minibuffer and completing-read now take an
9930 additional argument which specifies the default value. If this
9931 argument is non-nil, it should be a string; that string is used in two
9932 ways:
9933
9934 It is returned if the user enters empty input.
9935 It is available through the history command M-n.
9936
9937 *** The functions read-string, read-from-minibuffer,
9938 read-no-blanks-input and completing-read now take an additional
9939 argument INHERIT-INPUT-METHOD. If this is non-nil, then the
9940 minibuffer inherits the current input method and the setting of
9941 enable-multibyte-characters from the previously current buffer.
9942
9943 In an interactive spec, you can use M instead of s to read an
9944 argument in this way.
9945
9946 *** All minibuffer input functions discard text properties
9947 from the text you enter in the minibuffer, unless the variable
9948 minibuffer-allow-text-properties is non-nil.
9949
9950 ** Echo area features
9951
9952 *** Clearing the echo area now runs the normal hook
9953 echo-area-clear-hook. Note that the echo area can be used while the
9954 minibuffer is active; in that case, the minibuffer is still active
9955 after the echo area is cleared.
9956
9957 *** The function current-message returns the message currently displayed
9958 in the echo area, or nil if there is none.
9959
9960 ** Keyboard input features
9961
9962 *** tty-erase-char is a new variable that reports which character was
9963 set up as the terminal's erase character when time Emacs was started.
9964
9965 *** num-nonmacro-input-events is the total number of input events
9966 received so far from the terminal. It does not count those generated
9967 by keyboard macros.
9968
9969 ** Frame-related changes
9970
9971 *** make-frame runs the normal hook before-make-frame-hook just before
9972 creating a frame, and just after creating a frame it runs the abnormal
9973 hook after-make-frame-functions with the new frame as arg.
9974
9975 *** The new hook window-configuration-change-hook is now run every time
9976 the window configuration has changed. The frame whose configuration
9977 has changed is the selected frame when the hook is run.
9978
9979 *** Each frame now independently records the order for recently
9980 selected buffers, in its buffer-list frame parameter, so that the
9981 value of other-buffer is now based on the buffers recently displayed
9982 in the selected frame.
9983
9984 *** The value of the frame parameter vertical-scroll-bars
9985 is now `left', `right' or nil. A non-nil value specifies
9986 which side of the window to put the scroll bars on.
9987
9988 ** X Windows features
9989
9990 *** You can examine X resources for other applications by binding
9991 x-resource-class around a call to x-get-resource. The usual value of
9992 x-resource-class is "Emacs", which is the correct value for Emacs.
9993
9994 *** In menus, checkboxes and radio buttons now actually work.
9995 The menu displays the current status of the box or button.
9996
9997 *** The function x-list-fonts now takes an optional fourth argument
9998 MAXIMUM which sets a limit on how many matching fonts to return.
9999 A smaller value of MAXIMUM makes the function faster.
10000
10001 If the only question is whether *any* font matches the pattern,
10002 it is good to supply 1 for this argument.
10003
10004 ** Subprocess features
10005
10006 *** A reminder: it is no longer necessary for subprocess filter
10007 functions and sentinels to do save-match-data, because Emacs does this
10008 automatically.
10009
10010 *** The new function shell-command-to-string executes a shell command
10011 and returns the output from the command as a string.
10012
10013 *** The new function process-contact returns t for a child process,
10014 and (HOSTNAME SERVICE) for a net connection.
10015
10016 ** An error in running pre-command-hook or post-command-hook
10017 does clear the variable to nil. The documentation was wrong before.
10018
10019 ** In define-key-after, if AFTER is t, the new binding now always goes
10020 at the end of the keymap. If the keymap is a menu, this means it
10021 goes after the other menu items.
10022
10023 ** If you have a program that makes several changes in the same area
10024 of the buffer, you can use the macro combine-after-change-calls
10025 around that Lisp code to make it faster when after-change hooks
10026 are in use.
10027
10028 The macro arranges to call the after-change functions just once for a
10029 series of several changes--if that seems safe.
10030
10031 Don't alter the variables after-change-functions and
10032 after-change-function within the body of a combine-after-change-calls
10033 form.
10034
10035 ** If you define an abbrev (with define-abbrev) whose EXPANSION
10036 is not a string, then the abbrev does not expand in the usual sense,
10037 but its hook is still run.
10038
10039 ** Normally, the Lisp debugger is not used (even if you have enabled it)
10040 for errors that are handled by condition-case.
10041
10042 If you set debug-on-signal to a non-nil value, then the debugger is called
10043 regardless of whether there is a handler for the condition. This is
10044 useful for debugging problems that happen inside of a condition-case.
10045
10046 This mode of operation seems to be unreliable in other ways. Errors that
10047 are normal and ought to be handled, perhaps in timers or process
10048 filters, will instead invoke the debugger. So don't say you weren't
10049 warned.
10050
10051 ** The new variable ring-bell-function lets you specify your own
10052 way for Emacs to "ring the bell".
10053
10054 ** If run-at-time's TIME argument is t, the action is repeated at
10055 integral multiples of REPEAT from the epoch; this is useful for
10056 functions like display-time.
10057
10058 ** You can use the function locate-library to find the precise file
10059 name of a Lisp library. This isn't new, but wasn't documented before.
10060
10061 ** Commands for entering view mode have new optional arguments that
10062 can be used from Lisp. Low-level entrance to and exit from view mode
10063 is done by functions view-mode-enter and view-mode-exit.
10064
10065 ** batch-byte-compile-file now makes Emacs return a nonzero status code
10066 if there is an error in compilation.
10067
10068 ** pop-to-buffer, switch-to-buffer-other-window and
10069 switch-to-buffer-other-frame now accept an additional optional
10070 argument NORECORD, much like switch-to-buffer. If it is non-nil,
10071 they don't put the buffer at the front of the buffer list.
10072
10073 ** If your .emacs file leaves the *scratch* buffer non-empty,
10074 Emacs does not display the startup message, so as to avoid changing
10075 the *scratch* buffer.
10076
10077 ** The new function regexp-opt returns an efficient regexp to match a string.
10078 The arguments are STRINGS and (optionally) PAREN. This function can be used
10079 where regexp matching or searching is intensively used and speed is important,
10080 e.g., in Font Lock mode.
10081
10082 ** The variable buffer-display-count is local to each buffer,
10083 and is incremented each time the buffer is displayed in a window.
10084 It starts at 0 when the buffer is created.
10085
10086 ** The new function compose-mail starts composing a mail message
10087 using the user's chosen mail composition agent (specified with the
10088 variable mail-user-agent). It has variants compose-mail-other-window
10089 and compose-mail-other-frame.
10090
10091 ** The `user-full-name' function now takes an optional parameter which
10092 can either be a number (the UID) or a string (the login name). The
10093 full name of the specified user will be returned.
10094
10095 ** Lisp packages that load files of customizations, or any other sort
10096 of user profile, should obey the variable init-file-user in deciding
10097 where to find it. They should load the profile of the user name found
10098 in that variable. If init-file-user is nil, meaning that the -q
10099 option was used, then Lisp packages should not load the customization
10100 files at all.
10101
10102 ** format-time-string now allows you to specify the field width
10103 and type of padding. This works as in printf: you write the field
10104 width as digits in the middle of a %-construct. If you start
10105 the field width with 0, it means to pad with zeros.
10106
10107 For example, %S normally specifies the number of seconds since the
10108 minute; %03S means to pad this with zeros to 3 positions, %_3S to pad
10109 with spaces to 3 positions. Plain %3S pads with zeros, because that
10110 is how %S normally pads to two positions.
10111
10112 ** thing-at-point now supports a new kind of "thing": url.
10113
10114 ** imenu.el changes.
10115
10116 You can now specify a function to be run when selecting an
10117 item from menu created by imenu.
10118
10119 An example of using this feature: if we define imenu items for the
10120 #include directives in a C file, we can open the included file when we
10121 select one of those items.
10122 \f
10123 * For older news, see the file ONEWS
10124
10125 ----------------------------------------------------------------------
10126 Copyright information:
10127
10128 Copyright (C) 1999, 2000, 2001 Free Software Foundation, Inc.
10129
10130 Permission is granted to anyone to make or distribute verbatim copies
10131 of this document as received, in any medium, provided that the
10132 copyright notice and this permission notice are preserved,
10133 thus giving the recipient permission to redistribute in turn.
10134
10135 Permission is granted to distribute modified versions
10136 of this document, or of portions of it,
10137 under the above conditions, provided also that they
10138 carry prominent notices stating who last changed them.
10139 \f
10140 Local variables:
10141 mode: outline
10142 paragraph-separate: "[ \f]*$"
10143 end: