Mention --no-window-system changes in the NEWS.
[bpt/emacs.git] / etc / NEWS
1 GNU Emacs NEWS -- history of user-visible changes. 2001-03-15
2 Copyright (C) 1999, 2000, 2001 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 \f
9 * Changes in Emacs 21.2
10
11 +++
12 ** The command line option --no-windows has been changed to
13 --no-window-system. The old one still works, but is deprecated.
14
15 ** `buffer-menu' and `list-buffers' now list buffers whose names begin
16 with a space, if they visit files.
17
18 ** tab-always-indent can be set to `never' to make sure indent-for-tab-command
19 always tabs rather than indents.
20
21 ** You can now customize fill-nobreak-predicate to control where
22 filling can break lines. We provide two sample predicates,
23 fill-single-word-nobreak-p and fill-french-nobreak-p.
24
25 ** In Texinfo mode, when Font-Lock is enabled, updating one of the
26 `foo's in `@foo ... @end foo' updates the other one on the fly.
27
28 ** New user option `add-log-always-start-new-record'.
29 When this option is enabled, M-x add-change-log-entry will always
30 start a new record regardless of when the last record is.
31
32 ** New user option `sgml-xml'.
33 When this option is enabled, SGML tags are inserted in XML style,
34 i.e., there is always a closing tag.
35 When not customized, it becomes buffer-local when it can be inferred
36 from the file name or buffer contents.
37
38 ** When the *scratch* buffer is recreated, its mode is set from
39 initial-major-mode, which normally is lisp-interaction-mode,
40 instead of using default-major-mode.
41
42 ** Byte compiler warning and error messages have been brought more
43 in line with the output of other GNU tools.
44
45 ** Lisp-mode now uses font-lock-doc-face for the docstrings.
46
47 ** perl-mode has a new variable `perl-indent-continued-arguments'.
48
49 ** `special-display-buffer-names' and `special-display-regexps' now
50 understand two new boolean pseudo-frame-parameters `same-frame' and
51 `same-window'.
52
53 ** When pure storage overflows while dumping, Emacs now prints how
54 much pure storage it will approximately need.
55
56 ** M-x setenv now expands environment variables of the form `$foo' and
57 `${foo}' in the specified new value of the environment variable. To
58 include a `$' in the value, use `$$'.
59
60 +++
61 ** File-name completion can now ignore directories.
62 If an element of the list in `completion-ignored-extensions' ends in a
63 slash `/', it indicates a subdirectory that should be ignored when
64 completing file names. Elements of `completion-ignored-extensions'
65 which do not end in a slash are never considered when a completion
66 candidate is a directory.
67
68 ** New user option `inhibit-startup-buffer-menu'.
69 When loading many files, for instance with `emacs *', Emacs normally
70 displays a buffer menu. This option turns the buffer menu off.
71
72 ** Rmail now displays 5-digit message ids in its summary buffer.
73
74 ** When using M-x revert-buffer in a compilation buffer to rerun a
75 compilation, it is now made sure that the compilation buffer is reused
76 in case it has been renamed.
77
78 ** New modes and packages
79
80 *** The ruler-mode.el library provides a minor mode for displaying an
81 "active" ruler in the header line. You can use the mouse to visually
82 change the `fill-column', `window-margins' and `tab-stop-list'
83 settings.
84
85 *** master-mode.el implements a minor mode for scrolling a slave
86 buffer without leaving your current buffer, the master buffer.
87
88 It can be used by sql.el, for example: the SQL buffer is the master
89 and its SQLi buffer is the slave. This allows you to scroll the SQLi
90 buffer containing the output from the SQL buffer containing the
91 commands.
92
93 This is how to use sql.el and master.el together: the variable
94 sql-buffer contains the slave buffer. It is a local variable in the
95 SQL buffer.
96
97 (add-hook 'sql-mode-hook
98 (function (lambda ()
99 (master-mode t)
100 (master-set-slave sql-buffer))))
101 (add-hook 'sql-set-sqli-hook
102 (function (lambda ()
103 (master-set-slave sql-buffer))))
104
105 \f
106 * Lisp Changes in Emacs 21.2
107
108 ** The default value of paragraph-start and indent-line-function has
109 been changed to reflect the one used in text-mode rather than the one
110 used in indented-text-mode.
111
112 ** New function `text-clone-create'. Text clones are chunks of text
113 that are kept identical by transparently propagating changes from one
114 clone to the other.
115
116 ** font-lock can manage arbitrary text-properties beside `face'.
117 *** the FACENAME returned in font-lock-keywords can be a list
118 of the form (face FACE PROP1 VAL1 PROP@ VAL2 ...) so you can set
119 other properties than `face'.
120 *** font-lock-extra-managed-props can be set to make sure those extra
121 properties are automatically cleaned up by font-lock.
122
123 ** The new function `run-mode-hooks' and the new macro `delay-mode-hooks'
124 are used by define-derived-mode to make sure the mode hook for the
125 parent mode is run at the end of the child mode.
126
127 ** `provide' and `featurep' now accept an optional second argument
128 to test/provide subfeatures. Also `provide' now checks `after-load-alist'
129 and run any code associated with the provided feature.
130
131 ** The variable `compilation-parse-errors-filename-function' can
132 be used to transform filenames found in compilation output.
133
134 +++
135 ** Functions `file-name-sans-extension' and `file-name-extension' now
136 ignore the leading dots in file names, so that file names such as
137 `.emacs' are treated as extensionless.
138
139 ** Functions `user-uid' and `user-real-uid' now return floats if the
140 user UID doesn't fit in a Lisp integer. Function `user-full-name'
141 accepts a float as UID parameter.
142
143 ** `define-key-after' now accepts keys longer than 1.
144
145 ** `define-derived-mode' now accepts nil as the parent.
146
147 ** The local variable `no-byte-compile' in elisp files is now obeyed.
148
149 ** New functions `keymap-prompt' and `current-active-maps'.
150
151 ** New function `describe-buffer-bindings'.
152
153 ** New vars `exec-suffixes' and `load-suffixes' used when
154 searching for an executable resp. an elisp file.
155
156 ** Variable aliases have been implemented
157
158 - Macro: defvaralias ALIAS-VAR BASE-VAR
159
160 This defines the symbol ALIAS-VAR as a variable alias for symbol
161 BASE-VAR. This means that retrieving the value of ALIAS-VAR returns
162 the value of BASE-VAR, and changing the value of ALIAS-VAR changes the
163 value of BASE-VAR.
164
165 - Function: indirect-variable VARIABLE
166
167 This function returns the variable at the end of the chain of aliases
168 of VARIABLE. If VARIABLE is not a symbol, or if VARIABLE is not
169 defined as an alias, the function returns VARIABLE.
170
171 It might be noteworthy that variables aliases work for all kinds of
172 variables, including buffer-local and frame-local variables.
173
174 ** Functions from `post-gc-hook' are run at the end of garbage
175 collection. The hook is run with GC inhibited, so use it with care.
176
177 ** If the second argument to `copy-file' is the name of a directory,
178 the file is copied to that directory instead of signaling an error.
179
180 ** The variables most-positive-fixnum and most-negative-fixnum
181 have been moved from the CL package to the core.
182
183 ** New packages:
184
185 *** The new package syntax.el provides an efficient way to find the
186 current syntactic context (as returned by parse-partial-sexp).
187
188 \f
189 * Installation Changes in Emacs 21.1
190
191 See the INSTALL file for information on installing extra libraries and
192 fonts to take advantage of the new graphical features and extra
193 charsets in this release.
194
195 ** Support for GNU/Linux on IA64 machines has been added.
196
197 ** Support for LynxOS has been added.
198
199 ** There are new configure options associated with the support for
200 images and toolkit scrollbars. Use the --help option in `configure'
201 to list them.
202
203 ** You can build a 64-bit Emacs for SPARC/Solaris systems which
204 support 64-bit executables and also on Irix 6.5. This increases the
205 maximum buffer size. See etc/MACHINES for instructions. Changes to
206 build on other 64-bit systems should be straightforward modulo any
207 necessary changes to unexec.
208
209 ** There is a new configure option `--disable-largefile' to omit
210 Unix-98-style support for large files if that is available.
211
212 ** There is a new configure option `--without-xim' that instructs
213 Emacs to not use X Input Methods (XIM), if these are available.
214
215 ** `movemail' defaults to supporting POP. You can turn this off using
216 the --without-pop configure option, should that be necessary.
217
218 ** This version can be built for the Macintosh, but does not implement
219 all of the new display features described below. The port currently
220 lacks unexec, asynchronous processes, and networking support. See the
221 "Emacs and the Mac OS" appendix in the Emacs manual, for the
222 description of aspects specific to the Mac.
223
224 ** Note that the MS-Windows port does not yet implement various of the
225 new display features described below.
226
227 \f
228 * Changes in Emacs 21.1
229
230 ** Emacs has a new redisplay engine.
231
232 The new redisplay handles characters of variable width and height.
233 Italic text can be used without redisplay problems. Fonts containing
234 oversized characters, i.e. characters larger than the logical height
235 of a font can be used. Images of various formats can be displayed in
236 the text.
237
238 ** Emacs has a new face implementation.
239
240 The new faces no longer fundamentally use X font names to specify the
241 font. Instead, each face has several independent attributes--family,
242 height, width, weight and slant--that it may or may not specify.
243 These attributes can be merged from various faces, and then together
244 specify a font.
245
246 Faces are supported on terminals that can display color or fonts.
247 These terminal capabilities are auto-detected. Details can be found
248 under Lisp changes, below.
249
250 ** Emacs can display faces on TTY frames.
251
252 Emacs automatically detects terminals that are able to display colors.
253 Faces with a weight greater than normal are displayed extra-bright, if
254 the terminal supports it. Faces with a weight less than normal and
255 italic faces are displayed dimmed, if the terminal supports it.
256 Underlined faces are displayed underlined if possible. Other face
257 attributes such as `overline', `strike-through', and `box' are ignored
258 on terminals.
259
260 The command-line options `-fg COLOR', `-bg COLOR', and `-rv' are now
261 supported on character terminals.
262
263 Emacs automatically remaps all X-style color specifications to one of
264 the colors supported by the terminal. This means you could have the
265 same color customizations that work both on a windowed display and on
266 a TTY or when Emacs is invoked with the -nw option.
267
268 ** New default font is Courier 12pt under X.
269
270 ** Sound support
271
272 Emacs supports playing sound files on GNU/Linux and FreeBSD (Voxware
273 driver and native BSD driver, a.k.a. Luigi's driver). Currently
274 supported file formats are RIFF-WAVE (*.wav) and Sun Audio (*.au).
275 You must configure Emacs with the option `--with-sound=yes' to enable
276 sound support.
277
278 ** Emacs now resizes mini-windows if appropriate.
279
280 If a message is longer than one line, or minibuffer contents are
281 longer than one line, Emacs can resize the minibuffer window unless it
282 is on a frame of its own. You can control resizing and the maximum
283 minibuffer window size by setting the following variables:
284
285 - User option: max-mini-window-height
286
287 Maximum height for resizing mini-windows. If a float, it specifies a
288 fraction of the mini-window frame's height. If an integer, it
289 specifies a number of lines.
290
291 Default is 0.25.
292
293 - User option: resize-mini-windows
294
295 How to resize mini-windows. If nil, don't resize. If t, always
296 resize to fit the size of the text. If `grow-only', let mini-windows
297 grow only, until they become empty, at which point they are shrunk
298 again.
299
300 Default is `grow-only'.
301
302 ** LessTif support.
303
304 Emacs now runs with the LessTif toolkit (see
305 <http://www.lesstif.org>). You will need version 0.92.26, or later.
306
307 ** LessTif/Motif file selection dialog.
308
309 When Emacs is configured to use LessTif or Motif, reading a file name
310 from a menu will pop up a file selection dialog if `use-dialog-box' is
311 non-nil.
312
313 ** File selection dialog on MS-Windows is supported.
314
315 When a file is visited by clicking File->Open, the MS-Windows version
316 now pops up a standard file selection dialog where you can select a
317 file to visit. File->Save As also pops up that dialog.
318
319 ** Toolkit scroll bars.
320
321 Emacs now uses toolkit scroll bars if available. When configured for
322 LessTif/Motif, it will use that toolkit's scroll bar. Otherwise, when
323 configured for Lucid and Athena widgets, it will use the Xaw3d scroll
324 bar if Xaw3d is available. You can turn off the use of toolkit scroll
325 bars by specifying `--with-toolkit-scroll-bars=no' when configuring
326 Emacs.
327
328 When you encounter problems with the Xaw3d scroll bar, watch out how
329 Xaw3d is compiled on your system. If the Makefile generated from
330 Xaw3d's Imakefile contains a `-DNARROWPROTO' compiler option, and your
331 Emacs system configuration file `s/your-system.h' does not contain a
332 define for NARROWPROTO, you might consider adding it. Take
333 `s/freebsd.h' as an example.
334
335 Alternatively, if you don't have access to the Xaw3d source code, take
336 a look at your system's imake configuration file, for example in the
337 directory `/usr/X11R6/lib/X11/config' (paths are different on
338 different systems). You will find files `*.cf' there. If your
339 system's cf-file contains a line like `#define NeedWidePrototypes NO',
340 add a `#define NARROWPROTO' to your Emacs system configuration file.
341
342 The reason for this is that one Xaw3d function uses `double' or
343 `float' function parameters depending on the setting of NARROWPROTO.
344 This is not a problem when Imakefiles are used because each system's
345 imake configuration file contains the necessary information. Since
346 Emacs doesn't use imake, this has do be done manually.
347
348 ** Tool bar support.
349
350 Emacs supports a tool bar at the top of a frame under X. For details
351 of how to define a tool bar, see the page describing Lisp-level
352 changes. Tool-bar global minor mode controls whether or not it is
353 displayed and is on by default. The appearance of the bar is improved
354 if Emacs has been built with XPM image support. Otherwise monochrome
355 icons will be used.
356
357 To make the tool bar more useful, we need contributions of extra icons
358 for specific modes (with copyright assignments). Contributions would
359 also be useful to touch up some of the PBM icons manually.
360
361 ** Tooltips.
362
363 Tooltips are small X windows displaying a help string at the current
364 mouse position. The Lisp package `tooltip' implements them. You can
365 turn them off via the user option `tooltip-mode'.
366
367 Tooltips also provides support for GUD debugging. If activated,
368 variable values can be displayed in tooltips by pointing at them with
369 the mouse in source buffers. You can customize various aspects of the
370 tooltip display in the group `tooltip'.
371
372 ** Automatic Hscrolling
373
374 Horizontal scrolling now happens automatically if
375 `automatic-hscrolling' is set (the default). This setting can be
376 customized.
377
378 If a window is scrolled horizontally with set-window-hscroll, or
379 scroll-left/scroll-right (C-x <, C-x >), this serves as a lower bound
380 for automatic horizontal scrolling. Automatic scrolling will scroll
381 the text more to the left if necessary, but won't scroll the text more
382 to the right than the column set with set-window-hscroll etc.
383
384 ** When using a windowing terminal, each Emacs window now has a cursor
385 of its own. By default, when a window is selected, the cursor is
386 solid; otherwise, it is hollow. The user-option
387 `cursor-in-non-selected-windows' controls how to display the
388 cursor in non-selected windows. If nil, no cursor is shown, if
389 non-nil a hollow box cursor is shown.
390
391 ** Fringes to the left and right of windows are used to display
392 truncation marks, continuation marks, overlay arrows and alike. The
393 foreground, background, and stipple of these areas can be changed by
394 customizing face `fringe'.
395
396 ** The mode line under X is now drawn with shadows by default.
397 You can change its appearance by modifying the face `mode-line'.
398 In particular, setting the `:box' attribute to nil turns off the 3D
399 appearance of the mode line. (The 3D appearance makes the mode line
400 occupy more space, and thus might cause the first or the last line of
401 the window to be partially obscured.)
402
403 The variable `mode-line-inverse-video', which was used in older
404 versions of emacs to make the mode-line stand out, is now deprecated.
405 However, setting it to nil will cause the `mode-line' face to be
406 ignored, and mode-lines to be drawn using the default text face.
407
408 ** Mouse-sensitive mode line.
409
410 Different parts of the mode line have been made mouse-sensitive on all
411 systems which support the mouse. Moving the mouse to a
412 mouse-sensitive part in the mode line changes the appearance of the
413 mouse pointer to an arrow, and help about available mouse actions is
414 displayed either in the echo area, or in the tooltip window if you
415 have enabled one.
416
417 Currently, the following actions have been defined:
418
419 - Mouse-1 on the buffer name in the mode line switches between two
420 buffers.
421
422 - Mouse-2 on the buffer-name switches to the next buffer, and
423 M-mouse-2 switches to the previous buffer in the buffer list.
424
425 - Mouse-3 on the buffer-name displays a buffer menu.
426
427 - Mouse-2 on the read-only or modified status in the mode line (`%' or
428 `*') toggles the status.
429
430 - Mouse-3 on the mode name displays a minor-mode menu.
431
432 ** Hourglass pointer
433
434 Emacs can optionally display an hourglass pointer under X. You can
435 turn the display on or off by customizing group `cursor'.
436
437 ** Blinking cursor
438
439 M-x blink-cursor-mode toggles a blinking cursor under X and on
440 terminals having terminal capabilities `vi', `vs', and `ve'. Blinking
441 and related parameters like frequency and delay can be customized in
442 the group `cursor'.
443
444 ** New font-lock support mode `jit-lock-mode'.
445
446 This support mode is roughly equivalent to `lazy-lock' but is
447 generally faster. It supports stealth and deferred fontification.
448 See the documentation of the function `jit-lock-mode' for more
449 details.
450
451 Font-lock uses jit-lock-mode as default support mode, so you don't
452 have to do anything to activate it.
453
454 ** The default binding of the Delete key has changed.
455
456 The new user-option `normal-erase-is-backspace' can be set to
457 determine the effect of the Delete and Backspace function keys.
458
459 On window systems, the default value of this option is chosen
460 according to the keyboard used. If the keyboard has both a Backspace
461 key and a Delete key, and both are mapped to their usual meanings, the
462 option's default value is set to t, so that Backspace can be used to
463 delete backward, and Delete can be used to delete forward. On
464 keyboards which either have only one key (usually labeled DEL), or two
465 keys DEL and BS which produce the same effect, the option's value is
466 set to nil, and these keys delete backward.
467
468 If not running under a window system, setting this option accomplishes
469 a similar effect by mapping C-h, which is usually generated by the
470 Backspace key, to DEL, and by mapping DEL to C-d via
471 `keyboard-translate'. The former functionality of C-h is available on
472 the F1 key. You should probably not use this setting on a text-only
473 terminal if you don't have both Backspace, Delete and F1 keys.
474
475 Programmatically, you can call function normal-erase-is-backspace-mode
476 to toggle the behavior of the Delete and Backspace keys.
477
478 ** The default for user-option `next-line-add-newlines' has been
479 changed to nil, i.e. C-n will no longer add newlines at the end of a
480 buffer by default.
481
482 ** The <home> and <end> keys now move to the beginning or end of the
483 current line, respectively. C-<home> and C-<end> move to the
484 beginning and end of the buffer.
485
486 ** Emacs now checks for recursive loads of Lisp files. If the
487 recursion depth exceeds `recursive-load-depth-limit', an error is
488 signaled.
489
490 ** When an error is signaled during the loading of the user's init
491 file, Emacs now pops up the *Messages* buffer.
492
493 ** Emacs now refuses to load compiled Lisp files which weren't
494 compiled with Emacs. Set `load-dangerous-libraries' to t to change
495 this behavior.
496
497 The reason for this change is an incompatible change in XEmacs's byte
498 compiler. Files compiled with XEmacs can contain byte codes that let
499 Emacs dump core.
500
501 ** Toggle buttons and radio buttons in menus.
502
503 When compiled with LessTif (or Motif) support, Emacs uses toolkit
504 widgets for radio and toggle buttons in menus. When configured for
505 Lucid, Emacs draws radio buttons and toggle buttons similar to Motif.
506
507 ** The menu bar configuration has changed. The new configuration is
508 more CUA-compliant. The most significant change is that Options is
509 now a separate menu-bar item, with Mule and Customize as its submenus.
510
511 ** Item Save Options on the Options menu allows saving options set
512 using that menu.
513
514 ** Highlighting of trailing whitespace.
515
516 When `show-trailing-whitespace' is non-nil, Emacs displays trailing
517 whitespace in the face `trailing-whitespace'. Trailing whitespace is
518 defined as spaces or tabs at the end of a line. To avoid busy
519 highlighting when entering new text, trailing whitespace is not
520 displayed if point is at the end of the line containing the
521 whitespace.
522
523 ** C-x 5 1 runs the new command delete-other-frames which deletes
524 all frames except the selected one.
525
526 ** The new user-option `confirm-kill-emacs' can be customized to
527 let Emacs ask for confirmation before exiting.
528
529 ** The header line in an Info buffer is now displayed as an emacs
530 header-line (which is like a mode-line, but at the top of the window),
531 so that it remains visible even when the buffer has been scrolled.
532 This behavior may be disabled by customizing the option
533 `Info-use-header-line'.
534
535 ** Polish, Czech, German, and French translations of Emacs' reference card
536 have been added. They are named `pl-refcard.tex', `cs-refcard.tex',
537 `de-refcard.tex' and `fr-refcard.tex'. Postscript files are included.
538
539 ** An `Emacs Survival Guide', etc/survival.tex, is available.
540
541 ** A reference card for Dired has been added. Its name is
542 `dired-ref.tex'. A French translation is available in
543 `fr-drdref.tex'.
544
545 ** C-down-mouse-3 is bound differently. Now if the menu bar is not
546 displayed it pops up a menu containing the items which would be on the
547 menu bar. If the menu bar is displayed, it pops up the major mode
548 menu or the Edit menu if there is no major mode menu.
549
550 ** Variable `load-path' is no longer customizable through Customize.
551
552 You can no longer use `M-x customize-variable' to customize `load-path'
553 because it now contains a version-dependent component. You can still
554 use `add-to-list' and `setq' to customize this variable in your
555 `~/.emacs' init file or to modify it from any Lisp program in general.
556
557 ** C-u C-x = provides detailed information about the character at
558 point in a pop-up window.
559
560 ** Emacs can now support 'wheeled' mice (such as the MS IntelliMouse)
561 under XFree86. To enable this, use the `mouse-wheel-mode' command, or
562 customize the variable `mouse-wheel-mode'.
563
564 The variables `mouse-wheel-follow-mouse' and `mouse-wheel-scroll-amount'
565 determine where and by how much buffers are scrolled.
566
567 ** Emacs' auto-save list files are now by default stored in a
568 sub-directory `.emacs.d/auto-save-list/' of the user's home directory.
569 (On MS-DOS, this subdirectory's name is `_emacs.d/auto-save.list/'.)
570 You can customize `auto-save-list-file-prefix' to change this location.
571
572 ** The function `getenv' is now callable interactively.
573
574 ** The new user-option `even-window-heights' can be set to nil
575 to prevent `display-buffer' from evening out window heights.
576
577 ** The new command M-x delete-trailing-whitespace RET will delete the
578 trailing whitespace within the current restriction. You can also add
579 this function to `write-file-hooks' or `local-write-file-hooks'.
580
581 ** When visiting a file with M-x find-file-literally, no newlines will
582 be added to the end of the buffer even if `require-final-newline' is
583 non-nil.
584
585 ** The new user-option `find-file-suppress-same-file-warnings' can be
586 set to suppress warnings ``X and Y are the same file'' when visiting a
587 file that is already visited under a different name.
588
589 ** The new user-option `electric-help-shrink-window' can be set to
590 nil to prevent adjusting the help window size to the buffer size.
591
592 ** New command M-x describe-character-set reads a character set name
593 and displays information about that.
594
595 ** The new variable `auto-mode-interpreter-regexp' contains a regular
596 expression matching interpreters, for file mode determination.
597
598 This regular expression is matched against the first line of a file to
599 determine the file's mode in `set-auto-mode' when Emacs can't deduce a
600 mode from the file's name. If it matches, the file is assumed to be
601 interpreted by the interpreter matched by the second group of the
602 regular expression. The mode is then determined as the mode
603 associated with that interpreter in `interpreter-mode-alist'.
604
605 ** New function executable-make-buffer-file-executable-if-script-p is
606 suitable as an after-save-hook as an alternative to `executable-chmod'.
607
608 ** The most preferred coding-system is now used to save a buffer if
609 buffer-file-coding-system is `undecided' and it is safe for the buffer
610 contents. (The most preferred is set by set-language-environment or
611 by M-x prefer-coding-system.) Thus if you visit an ASCII file and
612 insert a non-ASCII character from your current language environment,
613 the file will be saved silently with the appropriate coding.
614 Previously you would be prompted for a safe coding system.
615
616 ** The many obsolete language `setup-...-environment' commands have
617 been removed -- use `set-language-environment'.
618
619 ** The new Custom option `keyboard-coding-system' specifies a coding
620 system for keyboard input.
621
622 ** New variable `inhibit-iso-escape-detection' determines if Emacs'
623 coding system detection algorithm should pay attention to ISO2022's
624 escape sequences. If this variable is non-nil, the algorithm ignores
625 such escape sequences. The default value is nil, and it is
626 recommended not to change it except for the special case that you
627 always want to read any escape code verbatim. If you just want to
628 read a specific file without decoding escape codes, use C-x RET c
629 (`universal-coding-system-argument'). For instance, C-x RET c latin-1
630 RET C-x C-f filename RET.
631
632 ** Variable `default-korean-keyboard' is initialized properly from the
633 environment variable `HANGUL_KEYBOARD_TYPE'.
634
635 ** New command M-x list-charset-chars reads a character set name and
636 displays all characters in that character set.
637
638 ** M-x set-terminal-coding-system (C-x RET t) now allows CCL-based
639 coding systems such as cpXXX and cyrillic-koi8.
640
641 ** Emacs now attempts to determine the initial language environment
642 and preferred and locale coding systems systematically from the
643 LC_ALL, LC_CTYPE, and LANG environment variables during startup.
644
645 ** New language environments `Polish', `Latin-8' and `Latin-9'.
646 Latin-8 and Latin-9 correspond respectively to the ISO character sets
647 8859-14 (Celtic) and 8859-15 (updated Latin-1, with the Euro sign).
648 GNU Intlfonts doesn't support these yet but recent X releases have
649 8859-15. See etc/INSTALL for information on obtaining extra fonts.
650 There are new Leim input methods for Latin-8 and Latin-9 prefix (only)
651 and Polish `slash'.
652
653 ** New language environments `Dutch' and `Spanish'.
654 These new environments mainly select appropriate translations
655 of the tutorial.
656
657 ** In Ethiopic language environment, special key bindings for
658 function keys are changed as follows. This is to conform to "Emacs
659 Lisp Coding Convention".
660
661 new command old-binding
662 --- ------- -----------
663 f3 ethio-fidel-to-sera-buffer f5
664 S-f3 ethio-fidel-to-sera-region f5
665 C-f3 ethio-fidel-to-sera-mail-or-marker f5
666
667 f4 ethio-sera-to-fidel-buffer unchanged
668 S-f4 ethio-sera-to-fidel-region unchanged
669 C-f4 ethio-sera-to-fidel-mail-or-marker unchanged
670
671 S-f5 ethio-toggle-punctuation f3
672 S-f6 ethio-modify-vowel f6
673 S-f7 ethio-replace-space f7
674 S-f8 ethio-input-special-character f8
675 S-f9 ethio-replace-space unchanged
676 C-f9 ethio-toggle-space f2
677
678 ** There are new Leim input methods.
679 New input methods "turkish-postfix", "turkish-alt-postfix",
680 "greek-mizuochi", "TeX", and "greek-babel" are now part of the Leim
681 package.
682
683 ** The rule of input method "slovak" is slightly changed. Now the
684 rules for translating "q" and "Q" to "`" (backquote) are deleted, thus
685 typing them inserts "q" and "Q" respectively. Rules for translating
686 "=q", "+q", "=Q", and "+Q" to "`" are also deleted. Now, to input
687 "`", you must type "=q".
688
689 ** When your terminal can't display characters from some of the ISO
690 8859 character sets but can display Latin-1, you can display
691 more-or-less mnemonic sequences of ASCII/Latin-1 characters instead of
692 empty boxes (under a window system) or question marks (not under a
693 window system). Customize the option `latin1-display' to turn this
694 on.
695
696 ** M-; now calls comment-dwim which tries to do something clever based
697 on the context. M-x kill-comment is now an alias to comment-kill,
698 defined in newcomment.el. You can choose different styles of region
699 commenting with the variable `comment-style'.
700
701 ** New user options `display-time-mail-face' and
702 `display-time-use-mail-icon' control the appearance of mode-line mail
703 indicator used by the display-time package. On a suitable display the
704 indicator can be an icon and is mouse-sensitive.
705
706 ** On window-systems, additional space can be put between text lines
707 on the display using several methods
708
709 - By setting frame parameter `line-spacing' to PIXELS. PIXELS must be
710 a positive integer, and specifies that PIXELS number of pixels should
711 be put below text lines on the affected frame or frames.
712
713 - By setting X resource `lineSpacing', class `LineSpacing'. This is
714 equivalent to specifying the frame parameter.
715
716 - By specifying `--line-spacing=N' or `-lsp N' on the command line.
717
718 - By setting buffer-local variable `line-spacing'. The meaning is
719 the same, but applies to the a particular buffer only.
720
721 ** The new command `clone-indirect-buffer' can be used to create
722 an indirect buffer that is a twin copy of the current buffer. The
723 command `clone-indirect-buffer-other-window', bound to C-x 4 c,
724 does the same but displays the indirect buffer in another window.
725
726 ** New user options `backup-directory-alist' and
727 `make-backup-file-name-function' control the placement of backups,
728 typically in a single directory or in an invisible sub-directory.
729
730 ** New commands iso-iso2sgml and iso-sgml2iso convert between Latin-1
731 characters and the corresponding SGML (HTML) entities.
732
733 ** New X resources recognized
734
735 *** The X resource `synchronous', class `Synchronous', specifies
736 whether Emacs should run in synchronous mode. Synchronous mode
737 is useful for debugging X problems.
738
739 Example:
740
741 emacs.synchronous: true
742
743 *** The X resource `visualClass, class `VisualClass', specifies the
744 visual Emacs should use. The resource's value should be a string of
745 the form `CLASS-DEPTH', where CLASS is the name of the visual class,
746 and DEPTH is the requested color depth as a decimal number. Valid
747 visual class names are
748
749 TrueColor
750 PseudoColor
751 DirectColor
752 StaticColor
753 GrayScale
754 StaticGray
755
756 Visual class names specified as X resource are case-insensitive, i.e.
757 `pseudocolor', `Pseudocolor' and `PseudoColor' all have the same
758 meaning.
759
760 The program `xdpyinfo' can be used to list the visual classes
761 supported on your display, and which depths they have. If
762 `visualClass' is not specified, Emacs uses the display's default
763 visual.
764
765 Example:
766
767 emacs.visualClass: TrueColor-8
768
769 *** The X resource `privateColormap', class `PrivateColormap',
770 specifies that Emacs should use a private colormap if it is using the
771 default visual, and that visual is of class PseudoColor. Recognized
772 resource values are `true' or `on'.
773
774 Example:
775
776 emacs.privateColormap: true
777
778 ** Faces and frame parameters.
779
780 There are four new faces `scroll-bar', `border', `cursor' and `mouse'.
781 Setting the frame parameters `scroll-bar-foreground' and
782 `scroll-bar-background' sets foreground and background color of face
783 `scroll-bar' and vice versa. Setting frame parameter `border-color'
784 sets the background color of face `border' and vice versa. Likewise
785 for frame parameters `cursor-color' and face `cursor', and frame
786 parameter `mouse-color' and face `mouse'.
787
788 Changing frame parameter `font' sets font-related attributes of the
789 `default' face and vice versa. Setting frame parameters
790 `foreground-color' or `background-color' sets the colors of the
791 `default' face and vice versa.
792
793 ** New face `menu'.
794
795 The face `menu' can be used to change colors and font of Emacs' menus.
796
797 ** New frame parameter `screen-gamma' for gamma correction.
798
799 The new frame parameter `screen-gamma' specifies gamma-correction for
800 colors. Its value may be nil, the default, in which case no gamma
801 correction occurs, or a number > 0, usually a float, that specifies
802 the screen gamma of a frame's display.
803
804 PC monitors usually have a screen gamma of 2.2. smaller values result
805 in darker colors. You might want to try a screen gamma of 1.5 for LCD
806 color displays. The viewing gamma Emacs uses is 0.4545. (1/2.2).
807
808 The X resource name of this parameter is `screenGamma', class
809 `ScreenGamma'.
810
811 ** Tabs and variable-width text.
812
813 Tabs are now displayed with stretch properties; the width of a tab is
814 defined as a multiple of the normal character width of a frame, and is
815 independent of the fonts used in the text where the tab appears.
816 Thus, tabs can be used to line up text in different fonts.
817
818 ** Enhancements of the Lucid menu bar
819
820 *** The Lucid menu bar now supports the resource "margin".
821
822 emacs.pane.menubar.margin: 5
823
824 The default margin is 4 which makes the menu bar appear like the
825 LessTif/Motif one.
826
827 *** Arrows that indicate sub-menus are now drawn with shadows, as in
828 LessTif and Motif.
829
830 ** A block cursor can be drawn as wide as the glyph under it under X.
831
832 As an example: if a block cursor is over a tab character, it will be
833 drawn as wide as that tab on the display. To do this, set
834 `x-stretch-cursor' to a non-nil value.
835
836 ** Empty display lines at the end of a buffer may be marked with a
837 bitmap (this is similar to the tilde displayed by vi and Less).
838
839 This behavior is activated by setting the buffer-local variable
840 `indicate-empty-lines' to a non-nil value. The default value of this
841 variable is found in `default-indicate-empty-lines'.
842
843 ** There is a new "aggressive" scrolling method.
844
845 When scrolling up because point is above the window start, if the
846 value of the buffer-local variable `scroll-up-aggressively' is a
847 number, Emacs chooses a new window start so that point ends up that
848 fraction of the window's height from the top of the window.
849
850 When scrolling down because point is below the window end, if the
851 value of the buffer-local variable `scroll-down-aggressively' is a
852 number, Emacs chooses a new window start so that point ends up that
853 fraction of the window's height from the bottom of the window.
854
855 ** You can now easily create new *Info* buffers using either
856 M-x clone-buffer, C-u m <entry> RET or C-u g <entry> RET.
857 M-x clone-buffer can also be used on *Help* and several other special
858 buffers.
859
860 ** The command `Info-search' now uses a search history.
861
862 ** Listing buffers with M-x list-buffers (C-x C-b) now shows
863 abbreviated file names. Abbreviations can be customized by changing
864 `directory-abbrev-alist'.
865
866 ** A new variable, backup-by-copying-when-privileged-mismatch, gives
867 the highest file uid for which backup-by-copying-when-mismatch will be
868 forced on. The assumption is that uids less than or equal to this
869 value are special uids (root, bin, daemon, etc.--not real system
870 users) and that files owned by these users should not change ownership,
871 even if your system policy allows users other than root to edit them.
872
873 The default is 200; set the variable to nil to disable the feature.
874
875 ** The rectangle commands now avoid inserting undesirable spaces,
876 notably at the end of lines.
877
878 All these functions have been rewritten to avoid inserting unwanted
879 spaces, and an optional prefix now allows them to behave the old way.
880
881 ** The function `replace-rectangle' is an alias for `string-rectangle'.
882
883 ** The new command M-x string-insert-rectangle is like `string-rectangle',
884 but inserts text instead of replacing it.
885
886 ** The new command M-x query-replace-regexp-eval acts like
887 query-replace-regexp, but takes a Lisp expression which is evaluated
888 after each match to get the replacement text.
889
890 ** M-x query-replace recognizes a new command `e' (or `E') that lets
891 you edit the replacement string.
892
893 ** The new command mail-abbrev-complete-alias, bound to `M-TAB'
894 (if you load the library `mailabbrev'), lets you complete mail aliases
895 in the text, analogous to lisp-complete-symbol.
896
897 ** The variable `echo-keystrokes' may now have a floating point value.
898
899 ** If your init file is compiled (.emacs.elc), `user-init-file' is set
900 to the source name (.emacs.el), if that exists, after loading it.
901
902 ** The help string specified for a menu-item whose definition contains
903 the property `:help HELP' is now displayed under X, on MS-Windows, and
904 MS-DOS, either in the echo area or with tooltips. Many standard menus
905 displayed by Emacs now have help strings.
906
907 --
908 ** New user option `read-mail-command' specifies a command to use to
909 read mail from the menu etc.
910
911 ** The environment variable `EMACSLOCKDIR' is no longer used on MS-Windows.
912 This environment variable was used when creating lock files. Emacs on
913 MS-Windows does not use this variable anymore. This change was made
914 before Emacs 21.1, but wasn't documented until now.
915
916 ** Highlighting of mouse-sensitive regions is now supported in the
917 MS-DOS version of Emacs.
918
919 ** The new command `msdos-set-mouse-buttons' forces the MS-DOS version
920 of Emacs to behave as if the mouse had a specified number of buttons.
921 This comes handy with mice that don't report their number of buttons
922 correctly. One example is the wheeled mice, which report 3 buttons,
923 but clicks on the middle button are not passed to the MS-DOS version
924 of Emacs.
925
926 ** Customize changes
927
928 *** Customize now supports comments about customized items. Use the
929 `State' menu to add comments, or give a prefix argument to
930 M-x customize-set-variable or M-x customize-set-value. Note that
931 customization comments will cause the customizations to fail in
932 earlier versions of Emacs.
933
934 *** The new option `custom-buffer-done-function' says whether to kill
935 Custom buffers when you've done with them or just bury them (the
936 default).
937
938 *** If Emacs was invoked with the `-q' or `--no-init-file' options, it
939 does not allow you to save customizations in your `~/.emacs' init
940 file. This is because saving customizations from such a session would
941 wipe out all the other customizationss you might have on your init
942 file.
943
944 ** New features in evaluation commands
945
946 *** The commands to evaluate Lisp expressions, such as C-M-x in Lisp
947 modes, C-j in Lisp Interaction mode, and M-:, now bind the variables
948 print-level, print-length, and debug-on-error based on the new
949 customizable variables eval-expression-print-level,
950 eval-expression-print-length, and eval-expression-debug-on-error.
951
952 The default values for the first two of these variables are 12 and 4
953 respectively, which means that `eval-expression' now prints at most
954 the first 12 members of a list and at most 4 nesting levels deep (if
955 the list is longer or deeper than that, an ellipsis `...' is
956 printed).
957
958 <RET> or <mouse-2> on the printed text toggles between an abbreviated
959 printed representation and an unabbreviated one.
960
961 The default value of eval-expression-debug-on-error is t, so any error
962 during evaluation produces a backtrace.
963
964 *** The function `eval-defun' (C-M-x) now loads Edebug and instruments
965 code when called with a prefix argument.
966
967 ** CC mode changes.
968
969 Note: This release contains changes that might not be compatible with
970 current user setups (although it's believed that these
971 incompatibilities will only show in very uncommon circumstances).
972 However, since the impact is uncertain, these changes may be rolled
973 back depending on user feedback. Therefore there's no forward
974 compatibility guarantee wrt the new features introduced in this
975 release.
976
977 *** The hardcoded switch to "java" style in Java mode is gone.
978 CC Mode used to automatically set the style to "java" when Java mode
979 is entered. This has now been removed since it caused too much
980 confusion.
981
982 However, to keep backward compatibility to a certain extent, the
983 default value for c-default-style now specifies the "java" style for
984 java-mode, but "gnu" for all other modes (as before). So you won't
985 notice the change if you haven't touched that variable.
986
987 *** New cleanups, space-before-funcall and compact-empty-funcall.
988 Two new cleanups have been added to c-cleanup-list:
989
990 space-before-funcall causes a space to be inserted before the opening
991 parenthesis of a function call, which gives the style "foo (bar)".
992
993 compact-empty-funcall causes any space before a function call opening
994 parenthesis to be removed if there are no arguments to the function.
995 It's typically useful together with space-before-funcall to get the
996 style "foo (bar)" and "foo()".
997
998 *** Some keywords now automatically trigger reindentation.
999 Keywords like "else", "while", "catch" and "finally" have been made
1000 "electric" to make them reindent automatically when they continue an
1001 earlier statement. An example:
1002
1003 for (i = 0; i < 17; i++)
1004 if (a[i])
1005 res += a[i]->offset;
1006 else
1007
1008 Here, the "else" should be indented like the preceding "if", since it
1009 continues that statement. CC Mode will automatically reindent it after
1010 the "else" has been typed in full, since it's not until then it's
1011 possible to decide whether it's a new statement or a continuation of
1012 the preceding "if".
1013
1014 CC Mode uses Abbrev mode to achieve this, which is therefore turned on
1015 by default.
1016
1017 *** M-a and M-e now moves by sentence in multiline strings.
1018 Previously these two keys only moved by sentence in comments, which
1019 meant that sentence movement didn't work in strings containing
1020 documentation or other natural language text.
1021
1022 The reason it's only activated in multiline strings (i.e. strings that
1023 contain a newline, even when escaped by a '\') is to avoid stopping in
1024 the short strings that often reside inside statements. Multiline
1025 strings almost always contain text in a natural language, as opposed
1026 to other strings that typically contain format specifications,
1027 commands, etc. Also, it's not that bothersome that M-a and M-e misses
1028 sentences in single line strings, since they're short anyway.
1029
1030 *** Support for autodoc comments in Pike mode.
1031 Autodoc comments for Pike are used to extract documentation from the
1032 source, like Javadoc in Java. Pike mode now recognize this markup in
1033 comment prefixes and paragraph starts.
1034
1035 *** The comment prefix regexps on c-comment-prefix may be mode specific.
1036 When c-comment-prefix is an association list, it specifies the comment
1037 line prefix on a per-mode basis, like c-default-style does. This
1038 change came about to support the special autodoc comment prefix in
1039 Pike mode only.
1040
1041 *** Better handling of syntactic errors.
1042 The recovery after unbalanced parens earlier in the buffer has been
1043 improved; CC Mode now reports them by dinging and giving a message
1044 stating the offending line, but still recovers and indent the
1045 following lines in a sane way (most of the time). An "else" with no
1046 matching "if" is handled similarly. If an error is discovered while
1047 indenting a region, the whole region is still indented and the error
1048 is reported afterwards.
1049
1050 *** Lineup functions may now return absolute columns.
1051 A lineup function can give an absolute column to indent the line to by
1052 returning a vector with the desired column as the first element.
1053
1054 *** More robust and warning-free byte compilation.
1055 Although this is strictly not a user visible change (well, depending
1056 on the view of a user), it's still worth mentioning that CC Mode now
1057 can be compiled in the standard ways without causing trouble. Some
1058 code have also been moved between the subpackages to enhance the
1059 modularity somewhat. Thanks to Martin Buchholz for doing the
1060 groundwork.
1061
1062 *** c-style-variables-are-local-p now defaults to t.
1063 This is an incompatible change that has been made to make the behavior
1064 of the style system wrt global variable settings less confusing for
1065 non-advanced users. If you know what this variable does you might
1066 want to set it to nil in your .emacs, otherwise you probably don't
1067 have to bother.
1068
1069 Defaulting c-style-variables-are-local-p to t avoids the confusing
1070 situation that occurs when a user sets some style variables globally
1071 and edits both a Java and a non-Java file in the same Emacs session.
1072 If the style variables aren't buffer local in this case, loading of
1073 the second file will cause the default style (either "gnu" or "java"
1074 by default) to override the global settings made by the user.
1075
1076 *** New initialization procedure for the style system.
1077 When the initial style for a buffer is determined by CC Mode (from the
1078 variable c-default-style), the global values of style variables now
1079 take precedence over the values specified by the chosen style. This
1080 is different than the old behavior: previously, the style-specific
1081 settings would override the global settings. This change makes it
1082 possible to do simple configuration in the intuitive way with
1083 Customize or with setq lines in one's .emacs file.
1084
1085 By default, the global value of every style variable is the new
1086 special symbol set-from-style, which causes the value to be taken from
1087 the style system. This means that in effect, only an explicit setting
1088 of a style variable will cause the "overriding" behavior described
1089 above.
1090
1091 Also note that global settings override style-specific settings *only*
1092 when the initial style of a buffer is chosen by a CC Mode major mode
1093 function. When a style is chosen in other ways --- for example, by a
1094 call like (c-set-style "gnu") in a hook, or via M-x c-set-style ---
1095 then the style-specific values take precedence over any global style
1096 values. In Lisp terms, global values override style-specific values
1097 only when the new second argument to c-set-style is non-nil; see the
1098 function documentation for more info.
1099
1100 The purpose of these changes is to make it easier for users,
1101 especially novice users, to do simple customizations with Customize or
1102 with setq in their .emacs files. On the other hand, the new system is
1103 intended to be compatible with advanced users' customizations as well,
1104 such as those that choose styles in hooks or whatnot. This new system
1105 is believed to be almost entirely compatible with current
1106 configurations, in spite of the changed precedence between style and
1107 global variable settings when a buffer's default style is set.
1108
1109 (Thanks to Eric Eide for clarifying this explanation a bit.)
1110
1111 **** c-offsets-alist is now a customizable variable.
1112 This became possible as a result of the new initialization behavior.
1113
1114 This variable is treated slightly differently from the other style
1115 variables; instead of using the symbol set-from-style, it will be
1116 completed with the syntactic symbols it doesn't already contain when
1117 the style is first initialized. This means it now defaults to the
1118 empty list to make all syntactic elements get their values from the
1119 style system.
1120
1121 **** Compatibility variable to restore the old behavior.
1122 In case your configuration doesn't work with this change, you can set
1123 c-old-style-variable-behavior to non-nil to get the old behavior back
1124 as far as possible.
1125
1126 *** Improvements to line breaking and text filling.
1127 CC Mode now handles this more intelligently and seamlessly wrt the
1128 surrounding code, especially inside comments. For details see the new
1129 chapter about this in the manual.
1130
1131 **** New variable to recognize comment line prefix decorations.
1132 The variable c-comment-prefix-regexp has been added to properly
1133 recognize the line prefix in both block and line comments. It's
1134 primarily used to initialize the various paragraph recognition and
1135 adaptive filling variables that the text handling functions uses.
1136
1137 **** New variable c-block-comment-prefix.
1138 This is a generalization of the now obsolete variable
1139 c-comment-continuation-stars to handle arbitrary strings.
1140
1141 **** CC Mode now uses adaptive fill mode.
1142 This to make it adapt better to the paragraph style inside comments.
1143
1144 It's also possible to use other adaptive filling packages inside CC
1145 Mode, notably Kyle E. Jones' Filladapt mode (http://wonderworks.com/).
1146 A new convenience function c-setup-filladapt sets up Filladapt for use
1147 inside CC Mode.
1148
1149 Note though that the 2.12 version of Filladapt lacks a feature that
1150 causes it to work suboptimally when c-comment-prefix-regexp can match
1151 the empty string (which it commonly does). A patch for that is
1152 available from the CC Mode web site (http://www.python.org/emacs/
1153 cc-mode/).
1154
1155 **** The variables `c-hanging-comment-starter-p' and
1156 `c-hanging-comment-ender-p', which controlled how comment starters and
1157 enders were filled, are not used anymore. The new version of the
1158 function `c-fill-paragraph' keeps the comment starters and enders as
1159 they were before the filling.
1160
1161 **** It's now possible to selectively turn off auto filling.
1162 The variable c-ignore-auto-fill is used to ignore auto fill mode in
1163 specific contexts, e.g. in preprocessor directives and in string
1164 literals.
1165
1166 **** New context sensitive line break function c-context-line-break.
1167 It works like newline-and-indent in normal code, and adapts the line
1168 prefix according to the comment style when used inside comments. If
1169 you're normally using newline-and-indent, you might want to switch to
1170 this function.
1171
1172 *** Fixes to IDL mode.
1173 It now does a better job in recognizing only the constructs relevant
1174 to IDL. E.g. it no longer matches "class" as the beginning of a
1175 struct block, but it does match the CORBA 2.3 "valuetype" keyword.
1176 Thanks to Eric Eide.
1177
1178 *** Improvements to the Whitesmith style.
1179 It now keeps the style consistently on all levels and both when
1180 opening braces hangs and when they don't.
1181
1182 **** New lineup function c-lineup-whitesmith-in-block.
1183
1184 *** New lineup functions c-lineup-template-args and c-indent-multi-line-block.
1185 See their docstrings for details. c-lineup-template-args does a
1186 better job of tracking the brackets used as parens in C++ templates,
1187 and is used by default to line up continued template arguments.
1188
1189 *** c-lineup-comment now preserves alignment with a comment on the
1190 previous line. It used to instead preserve comments that started in
1191 the column specified by comment-column.
1192
1193 *** c-lineup-C-comments handles "free form" text comments.
1194 In comments with a long delimiter line at the start, the indentation
1195 is kept unchanged for lines that start with an empty comment line
1196 prefix. This is intended for the type of large block comments that
1197 contain documentation with its own formatting. In these you normally
1198 don't want CC Mode to change the indentation.
1199
1200 *** The `c' syntactic symbol is now relative to the comment start
1201 instead of the previous line, to make integers usable as lineup
1202 arguments.
1203
1204 *** All lineup functions have gotten docstrings.
1205
1206 *** More preprocessor directive movement functions.
1207 c-down-conditional does the reverse of c-up-conditional.
1208 c-up-conditional-with-else and c-down-conditional-with-else are
1209 variants of these that also stops at "#else" lines (suggested by Don
1210 Provan).
1211
1212 *** Minor improvements to many movement functions in tricky situations.
1213
1214 ** Dired changes
1215
1216 *** New variable `dired-recursive-deletes' determines if the delete
1217 command will delete non-empty directories recursively. The default
1218 is, delete only empty directories.
1219
1220 *** New variable `dired-recursive-copies' determines if the copy
1221 command will copy directories recursively. The default is, do not
1222 copy directories recursively.
1223
1224 *** In command `dired-do-shell-command' (usually bound to `!') a `?'
1225 in the shell command has a special meaning similar to `*', but with
1226 the difference that the command will be run on each file individually.
1227
1228 *** The new command `dired-find-alternate-file' (usually bound to `a')
1229 replaces the Dired buffer with the buffer for an alternate file or
1230 directory.
1231
1232 *** The new command `dired-show-file-type' (usually bound to `y') shows
1233 a message in the echo area describing what type of file the point is on.
1234 This command invokes the external program `file' do its work, and so
1235 will only work on systems with that program, and will be only as
1236 accurate or inaccurate as it is.
1237
1238 *** Dired now properly handles undo changes of adding/removing `-R'
1239 from ls switches.
1240
1241 *** Dired commands that prompt for a destination file now allow the use
1242 of the `M-n' command in the minibuffer to insert the source filename,
1243 which the user can then edit. This only works if there is a single
1244 source file, not when operating on multiple marked files.
1245
1246 ** Gnus changes.
1247
1248 The Gnus NEWS entries are short, but they reflect sweeping changes in
1249 four areas: Article display treatment, MIME treatment,
1250 internationalization and mail-fetching.
1251
1252 *** The mail-fetching functions have changed. See the manual for the
1253 many details. In particular, all procmail fetching variables are gone.
1254
1255 If you used procmail like in
1256
1257 (setq nnmail-use-procmail t)
1258 (setq nnmail-spool-file 'procmail)
1259 (setq nnmail-procmail-directory "~/mail/incoming/")
1260 (setq nnmail-procmail-suffix "\\.in")
1261
1262 this now has changed to
1263
1264 (setq mail-sources
1265 '((directory :path "~/mail/incoming/"
1266 :suffix ".in")))
1267
1268 More information is available in the info doc at Select Methods ->
1269 Getting Mail -> Mail Sources
1270
1271 *** Gnus is now a MIME-capable reader. This affects many parts of
1272 Gnus, and adds a slew of new commands. See the manual for details.
1273 Separate MIME packages like RMIME, mime-compose etc., will probably no
1274 longer work; remove them and use the native facilities.
1275
1276 The FLIM/SEMI package still works with Emacs 21, but if you want to
1277 use the native facilities, you must remove any mailcap.el[c] that was
1278 installed by FLIM/SEMI version 1.13 or earlier.
1279
1280 *** Gnus has also been multilingualized. This also affects too many
1281 parts of Gnus to summarize here, and adds many new variables. There
1282 are built-in facilities equivalent to those of gnus-mule.el, which is
1283 now just a compatibility layer.
1284
1285 *** gnus-mule.el is now just a compatibility layer over the built-in
1286 Gnus facilities.
1287
1288 *** gnus-auto-select-first can now be a function to be
1289 called to position point.
1290
1291 *** The user can now decide which extra headers should be included in
1292 summary buffers and NOV files.
1293
1294 *** `gnus-article-display-hook' has been removed. Instead, a number
1295 of variables starting with `gnus-treat-' have been added.
1296
1297 *** The Gnus posting styles have been redone again and now work in a
1298 subtly different manner.
1299
1300 *** New web-based backends have been added: nnslashdot, nnwarchive
1301 and nnultimate. nnweb has been revamped, again, to keep up with
1302 ever-changing layouts.
1303
1304 *** Gnus can now read IMAP mail via nnimap.
1305
1306 *** There is image support of various kinds and some sound support.
1307
1308 ** Changes in Texinfo mode.
1309
1310 *** A couple of new key bindings have been added for inserting Texinfo
1311 macros
1312
1313 Key binding Macro
1314 -------------------------
1315 C-c C-c C-s @strong
1316 C-c C-c C-e @emph
1317 C-c C-c u @uref
1318 C-c C-c q @quotation
1319 C-c C-c m @email
1320 C-c C-o @<block> ... @end <block>
1321 M-RET @item
1322
1323 *** The " key now inserts either " or `` or '' depending on context.
1324
1325 ** Changes in Outline mode.
1326
1327 There is now support for Imenu to index headings. A new command
1328 `outline-headers-as-kill' copies the visible headings in the region to
1329 the kill ring, e.g. to produce a table of contents.
1330
1331 ** Changes to Emacs Server
1332
1333 *** The new option `server-kill-new-buffers' specifies what to do
1334 with buffers when done with them. If non-nil, the default, buffers
1335 are killed, unless they were already present before visiting them with
1336 Emacs Server. If nil, `server-temp-file-regexp' specifies which
1337 buffers to kill, as before.
1338
1339 Please note that only buffers are killed that still have a client,
1340 i.e. buffers visited with `emacsclient --no-wait' are never killed in
1341 this way.
1342
1343 ** Both emacsclient and Emacs itself now accept command line options
1344 of the form +LINE:COLUMN in addition to +LINE.
1345
1346 ** Changes to Show Paren mode.
1347
1348 *** Overlays used by Show Paren mode now use a priority property.
1349 The new user option show-paren-priority specifies the priority to
1350 use. Default is 1000.
1351
1352 ** New command M-x check-parens can be used to find unbalanced paren
1353 groups and strings in buffers in Lisp mode (or other modes).
1354
1355 ** Changes to hideshow.el
1356
1357 *** Generalized block selection and traversal
1358
1359 A block is now recognized by its start and end regexps (both strings),
1360 and an integer specifying which sub-expression in the start regexp
1361 serves as the place where a `forward-sexp'-like function can operate.
1362 See the documentation of variable `hs-special-modes-alist'.
1363
1364 *** During incremental search, if Hideshow minor mode is active,
1365 hidden blocks are temporarily shown. The variable `hs-headline' can
1366 be used in the mode line format to show the line at the beginning of
1367 the open block.
1368
1369 *** User option `hs-hide-all-non-comment-function' specifies a
1370 function to be called at each top-level block beginning, instead of
1371 the normal block-hiding function.
1372
1373 *** The command `hs-show-region' has been removed.
1374
1375 *** The key bindings have changed to fit the Emacs conventions,
1376 roughly imitating those of Outline minor mode. Notably, the prefix
1377 for all bindings is now `C-c @'. For details, see the documentation
1378 for `hs-minor-mode'.
1379
1380 *** The variable `hs-show-hidden-short-form' has been removed, and
1381 hideshow.el now always behaves as if this variable were set to t.
1382
1383 ** Changes to Change Log mode and Add-Log functions
1384
1385 *** If you invoke `add-change-log-entry' from a backup file, it makes
1386 an entry appropriate for the file's parent. This is useful for making
1387 log entries by comparing a version with deleted functions.
1388
1389 **** New command M-x change-log-merge merges another log into the
1390 current buffer.
1391
1392 *** New command M-x change-log-redate fixes any old-style date entries
1393 in a log file.
1394
1395 *** Change Log mode now adds a file's version number to change log
1396 entries if user-option `change-log-version-info-enabled' is non-nil.
1397 Unless the file is under version control the search for a file's
1398 version number is performed based on regular expressions from
1399 `change-log-version-number-regexp-list' which can be customized.
1400 Version numbers are only found in the first 10 percent of a file.
1401
1402 *** Change Log mode now defines its own faces for font-lock highlighting.
1403
1404 ** Changes to cmuscheme
1405
1406 *** The user-option `scheme-program-name' has been renamed
1407 `cmuscheme-program-name' due to conflicts with xscheme.el.
1408
1409 ** Changes in Font Lock
1410
1411 *** The new function `font-lock-remove-keywords' can be used to remove
1412 font-lock keywords from the current buffer or from a specific major mode.
1413
1414 *** Multi-line patterns are now supported. Modes using this, should
1415 set font-lock-multiline to t in their font-lock-defaults.
1416
1417 *** `font-lock-syntactic-face-function' allows major-modes to choose
1418 the face used for each string/comment.
1419
1420 *** A new standard face `font-lock-doc-face'.
1421 Meant for Lisp docstrings, Javadoc comments and other "documentation in code".
1422
1423 ** Changes to Shell mode
1424
1425 *** The `shell' command now accepts an optional argument to specify the buffer
1426 to use, which defaults to "*shell*". When used interactively, a
1427 non-default buffer may be specified by giving the `shell' command a
1428 prefix argument (causing it to prompt for the buffer name).
1429
1430 ** Comint (subshell) changes
1431
1432 These changes generally affect all modes derived from comint mode, which
1433 include shell-mode, gdb-mode, scheme-interaction-mode, etc.
1434
1435 *** Comint now by default interprets some carriage-control characters.
1436 Comint now removes CRs from CR LF sequences, and treats single CRs and
1437 BSs in the output in a way similar to a terminal (by deleting to the
1438 beginning of the line, or deleting the previous character,
1439 respectively). This is achieved by adding `comint-carriage-motion' to
1440 the `comint-output-filter-functions' hook by default.
1441
1442 *** By default, comint no longer uses the variable `comint-prompt-regexp'
1443 to distinguish prompts from user-input. Instead, it notices which
1444 parts of the text were output by the process, and which entered by the
1445 user, and attaches `field' properties to allow emacs commands to use
1446 this information. Common movement commands, notably beginning-of-line,
1447 respect field boundaries in a fairly natural manner. To disable this
1448 feature, and use the old behavior, customize the user option
1449 `comint-use-prompt-regexp-instead-of-fields'.
1450
1451 *** Comint now includes new features to send commands to running processes
1452 and redirect the output to a designated buffer or buffers.
1453
1454 *** The command M-x comint-redirect-send-command reads a command and
1455 buffer name from the mini-buffer. The command is sent to the current
1456 buffer's process, and its output is inserted into the specified buffer.
1457
1458 The command M-x comint-redirect-send-command-to-process acts like
1459 M-x comint-redirect-send-command but additionally reads the name of
1460 the buffer whose process should be used from the mini-buffer.
1461
1462 *** Packages based on comint now highlight user input and program prompts,
1463 and support choosing previous input with mouse-2. To control these features,
1464 see the user-options `comint-highlight-input' and `comint-highlight-prompt'.
1465
1466 *** The new command `comint-write-output' (usually bound to `C-c C-s')
1467 saves the output from the most recent command to a file. With a prefix
1468 argument, it appends to the file.
1469
1470 *** The command `comint-kill-output' has been renamed `comint-delete-output'
1471 (usually bound to `C-c C-o'); the old name is aliased to it for
1472 compatibility.
1473
1474 *** The new function `comint-add-to-input-history' adds commands to the input
1475 ring (history).
1476
1477 *** The new variable `comint-input-history-ignore' is a regexp for
1478 identifying history lines that should be ignored, like tcsh time-stamp
1479 strings, starting with a `#'. The default value of this variable is "^#".
1480
1481 ** Changes to Rmail mode
1482
1483 *** The new user-option rmail-user-mail-address-regexp can be
1484 set to fine tune the identification of the correspondent when
1485 receiving new mail. If it matches the address of the sender, the
1486 recipient is taken as correspondent of a mail. If nil, the default,
1487 `user-login-name' and `user-mail-address' are used to exclude yourself
1488 as correspondent.
1489
1490 Usually you don't have to set this variable, except if you collect
1491 mails sent by you under different user names. Then it should be a
1492 regexp matching your mail addresses.
1493
1494 *** The new user-option rmail-confirm-expunge controls whether and how
1495 to ask for confirmation before expunging deleted messages from an
1496 Rmail file. You can choose between no confirmation, confirmation
1497 with y-or-n-p, or confirmation with yes-or-no-p. Default is to ask
1498 for confirmation with yes-or-no-p.
1499
1500 *** RET is now bound in the Rmail summary to rmail-summary-goto-msg,
1501 like `j'.
1502
1503 *** There is a new user option `rmail-digest-end-regexps' that
1504 specifies the regular expressions to detect the line that ends a
1505 digest message.
1506
1507 *** The new user option `rmail-automatic-folder-directives' specifies
1508 in which folder to put messages automatically.
1509
1510 *** The new function `rmail-redecode-body' allows to fix a message
1511 with non-ASCII characters if Emacs happens to decode it incorrectly
1512 due to missing or malformed "charset=" header.
1513
1514 ** The new user-option `mail-envelope-from' can be used to specify
1515 an envelope-from address different from user-mail-address.
1516
1517 ** The variable mail-specify-envelope-from controls whether to
1518 use the -f option when sending mail.
1519
1520 ** The Rmail command `o' (`rmail-output-to-rmail-file') now writes the
1521 current message in the internal `emacs-mule' encoding, rather than in
1522 the encoding taken from the variable `buffer-file-coding-system'.
1523 This allows to save messages whose characters cannot be safely encoded
1524 by the buffer's coding system, and makes sure the message will be
1525 displayed correctly when you later visit the target Rmail file.
1526
1527 If you want your Rmail files be encoded in a specific coding system
1528 other than `emacs-mule', you can customize the variable
1529 `rmail-file-coding-system' to set its value to that coding system.
1530
1531 ** Changes to TeX mode
1532
1533 *** The default mode has been changed from `plain-tex-mode' to
1534 `latex-mode'.
1535
1536 *** latex-mode now has a simple indentation algorithm.
1537
1538 *** M-f and M-p jump around \begin...\end pairs.
1539
1540 *** Added support for outline-minor-mode.
1541
1542 ** Changes to RefTeX mode
1543
1544 *** RefTeX has new support for index generation. Index entries can be
1545 created with `C-c <', with completion available on index keys.
1546 Pressing `C-c /' indexes the word at the cursor with a default
1547 macro. `C-c >' compiles all index entries into an alphabetically
1548 sorted *Index* buffer which looks like the final index. Entries
1549 can be edited from that buffer.
1550
1551 *** Label and citation key selection now allow to select several
1552 items and reference them together (use `m' to mark items, `a' or
1553 `A' to use all marked entries).
1554
1555 *** reftex.el has been split into a number of smaller files to reduce
1556 memory use when only a part of RefTeX is being used.
1557
1558 *** a new command `reftex-view-crossref-from-bibtex' (bound to `C-c &'
1559 in BibTeX-mode) can be called in a BibTeX database buffer in order
1560 to show locations in LaTeX documents where a particular entry has
1561 been cited.
1562
1563 ** Emacs Lisp mode now allows multiple levels of outline headings.
1564 The level of a heading is determined from the number of leading
1565 semicolons in a heading line. Toplevel forms starting with a `('
1566 in column 1 are always made leaves.
1567
1568 ** The M-x time-stamp command (most commonly used on write-file-hooks)
1569 has the following new features:
1570
1571 *** The patterns for finding the time stamp and for updating a pattern
1572 may match text spanning multiple lines. For example, some people like
1573 to have the filename and date on separate lines. The new variable
1574 time-stamp-inserts-lines controls the matching for multi-line patterns.
1575
1576 *** More than one time stamp can be updated in the same file. This
1577 feature is useful if you need separate time stamps in a program source
1578 file to both include in formatted documentation and insert in the
1579 compiled binary. The same time-stamp will be written at each matching
1580 pattern. The variable time-stamp-count enables this new feature; it
1581 defaults to 1.
1582
1583 ** Partial Completion mode now completes environment variables in
1584 file names.
1585
1586 ** Ispell changes
1587
1588 *** The command `ispell' now spell-checks a region if
1589 transient-mark-mode is on, and the mark is active. Otherwise it
1590 spell-checks the current buffer.
1591
1592 *** Support for synchronous subprocesses - DOS/Windoze - has been
1593 added.
1594
1595 *** An "alignment error" bug was fixed when a manual spelling
1596 correction is made and re-checked.
1597
1598 *** An Italian, Portuguese, and Slovak dictionary definition has been added.
1599
1600 *** Region skipping performance has been vastly improved in some
1601 cases.
1602
1603 *** Spell checking HTML buffers has been improved and isn't so strict
1604 on syntax errors.
1605
1606 *** The buffer-local words are now always placed on a new line at the
1607 end of the buffer.
1608
1609 *** Spell checking now works in the MS-DOS version of Emacs.
1610
1611 ** Makefile mode changes
1612
1613 *** The mode now uses the abbrev table `makefile-mode-abbrev-table'.
1614
1615 *** Conditionals and include statements are now highlighted when
1616 Fontlock mode is active.
1617
1618 ** Isearch changes
1619
1620 *** Isearch now puts a call to `isearch-resume' in the command history,
1621 so that searches can be resumed.
1622
1623 *** In Isearch mode, C-M-s and C-M-r are now bound like C-s and C-r,
1624 respectively, i.e. you can repeat a regexp isearch with the same keys
1625 that started the search.
1626
1627 *** In Isearch mode, mouse-2 in the echo area now yanks the current
1628 selection into the search string rather than giving an error.
1629
1630 *** There is a new lazy highlighting feature in incremental search.
1631
1632 Lazy highlighting is switched on/off by customizing variable
1633 `isearch-lazy-highlight'. When active, all matches for the current
1634 search string are highlighted. The current match is highlighted as
1635 before using face `isearch' or `region'. All other matches are
1636 highlighted using face `isearch-lazy-highlight-face' which defaults to
1637 `secondary-selection'.
1638
1639 The extra highlighting makes it easier to anticipate where the cursor
1640 will end up each time you press C-s or C-r to repeat a pending search.
1641 Highlighting of these additional matches happens in a deferred fashion
1642 using "idle timers," so the cycles needed do not rob isearch of its
1643 usual snappy response.
1644
1645 If `isearch-lazy-highlight-cleanup' is set to t, highlights for
1646 matches are automatically cleared when you end the search. If it is
1647 set to nil, you can remove the highlights manually with `M-x
1648 isearch-lazy-highlight-cleanup'.
1649
1650 ** VC Changes
1651
1652 VC has been overhauled internally. It is now modular, making it
1653 easier to plug-in arbitrary version control backends. (See Lisp
1654 Changes for details on the new structure.) As a result, the mechanism
1655 to enable and disable support for particular version systems has
1656 changed: everything is now controlled by the new variable
1657 `vc-handled-backends'. Its value is a list of symbols that identify
1658 version systems; the default is '(RCS CVS SCCS). When finding a file,
1659 each of the backends in that list is tried in order to see whether the
1660 file is registered in that backend.
1661
1662 When registering a new file, VC first tries each of the listed
1663 backends to see if any of them considers itself "responsible" for the
1664 directory of the file (e.g. because a corresponding subdirectory for
1665 master files exists). If none of the backends is responsible, then
1666 the first backend in the list that could register the file is chosen.
1667 As a consequence, the variable `vc-default-back-end' is now obsolete.
1668
1669 The old variable `vc-master-templates' is also obsolete, although VC
1670 still supports it for backward compatibility. To define templates for
1671 RCS or SCCS, you should rather use the new variables
1672 vc-{rcs,sccs}-master-templates. (There is no such feature under CVS
1673 where it doesn't make sense.)
1674
1675 The variables `vc-ignore-vc-files' and `vc-handle-cvs' are also
1676 obsolete now, you must set `vc-handled-backends' to nil or exclude
1677 `CVS' from the list, respectively, to achieve their effect now.
1678
1679 *** General Changes
1680
1681 The variable `vc-checkout-carefully' is obsolete: the corresponding
1682 checks are always done now.
1683
1684 VC Dired buffers are now kept up-to-date during all version control
1685 operations.
1686
1687 `vc-diff' output is now displayed in `diff-mode'.
1688 `vc-print-log' uses `log-view-mode'.
1689 `vc-log-mode' (used for *VC-Log*) has been replaced by `log-edit-mode'.
1690
1691 The command C-x v m (vc-merge) now accepts an empty argument as the
1692 first revision number. This means that any recent changes on the
1693 current branch should be picked up from the repository and merged into
1694 the working file (``merge news'').
1695
1696 The commands C-x v s (vc-create-snapshot) and C-x v r
1697 (vc-retrieve-snapshot) now ask for a directory name from which to work
1698 downwards.
1699
1700 *** Multiple Backends
1701
1702 VC now lets you register files in more than one backend. This is
1703 useful, for example, if you are working with a slow remote CVS
1704 repository. You can then use RCS for local editing, and occasionally
1705 commit your changes back to CVS, or pick up changes from CVS into your
1706 local RCS archives.
1707
1708 To make this work, the ``more local'' backend (RCS in our example)
1709 should come first in `vc-handled-backends', and the ``more remote''
1710 backend (CVS) should come later. (The default value of
1711 `vc-handled-backends' already has it that way.)
1712
1713 You can then commit changes to another backend (say, RCS), by typing
1714 C-u C-x v v RCS RET (i.e. vc-next-action now accepts a backend name as
1715 a revision number). VC registers the file in the more local backend
1716 if that hasn't already happened, and commits to a branch based on the
1717 current revision number from the more remote backend.
1718
1719 If a file is registered in multiple backends, you can switch to
1720 another one using C-x v b (vc-switch-backend). This does not change
1721 any files, it only changes VC's perspective on the file. Use this to
1722 pick up changes from CVS while working under RCS locally.
1723
1724 After you are done with your local RCS editing, you can commit your
1725 changes back to CVS using C-u C-x v v CVS RET. In this case, the
1726 local RCS archive is removed after the commit, and the log entry
1727 buffer is initialized to contain the entire RCS change log of the file.
1728
1729 *** Changes for CVS
1730
1731 There is a new user option, `vc-cvs-stay-local'. If it is `t' (the
1732 default), then VC avoids network queries for files registered in
1733 remote repositories. The state of such files is then only determined
1734 by heuristics and past information. `vc-cvs-stay-local' can also be a
1735 regexp to match against repository hostnames; only files from hosts
1736 that match it are treated locally. If the variable is nil, then VC
1737 queries the repository just as often as it does for local files.
1738
1739 If `vc-cvs-stay-local' is on, then VC also makes local backups of
1740 repository versions. This means that ordinary diffs (C-x v =) and
1741 revert operations (C-x v u) can be done completely locally, without
1742 any repository interactions at all. The name of a local version
1743 backup of FILE is FILE.~REV.~, where REV is the repository version
1744 number. This format is similar to that used by C-x v ~
1745 (vc-version-other-window), except for the trailing dot. As a matter
1746 of fact, the two features can each use the files created by the other,
1747 the only difference being that files with a trailing `.' are deleted
1748 automatically after commit. (This feature doesn't work on MS-DOS,
1749 since DOS disallows more than a single dot in the trunk of a file
1750 name.)
1751
1752 If `vc-cvs-stay-local' is on, and there have been changes in the
1753 repository, VC notifies you about it when you actually try to commit.
1754 If you want to check for updates from the repository without trying to
1755 commit, you can either use C-x v m RET to perform an update on the
1756 current file, or you can use C-x v r RET to get an update for an
1757 entire directory tree.
1758
1759 The new user option `vc-cvs-use-edit' indicates whether VC should call
1760 "cvs edit" to make files writeable; it defaults to `t'. (This option
1761 is only meaningful if the CVSREAD variable is set, or if files are
1762 "watched" by other developers.)
1763
1764 The commands C-x v s (vc-create-snapshot) and C-x v r
1765 (vc-retrieve-snapshot) are now also implemented for CVS. If you give
1766 an empty snapshot name to the latter, that performs a `cvs update',
1767 starting at the given directory.
1768
1769 *** Lisp Changes in VC
1770
1771 VC has been restructured internally to make it modular. You can now
1772 add support for arbitrary version control backends by writing a
1773 library that provides a certain set of backend-specific functions, and
1774 then telling VC to use that library. For example, to add support for
1775 a version system named SYS, you write a library named vc-sys.el, which
1776 provides a number of functions vc-sys-... (see commentary at the top
1777 of vc.el for a detailed list of them). To make VC use that library,
1778 you need to put it somewhere into Emacs' load path and add the symbol
1779 `SYS' to the list `vc-handled-backends'.
1780
1781 ** The customizable EDT emulation package now supports the EDT
1782 SUBS command and EDT scroll margins. It also works with more
1783 terminal/keyboard configurations and it now works under XEmacs.
1784 See etc/edt-user.doc for more information.
1785
1786 ** New modes and packages
1787
1788 *** The new global minor mode `minibuffer-electric-default-mode'
1789 automatically hides the `(default ...)' part of minibuffer prompts when
1790 the default is not applicable.
1791
1792 *** Artist is an Emacs lisp package that allows you to draw lines,
1793 rectangles and ellipses by using your mouse and/or keyboard. The
1794 shapes are made up with the ascii characters |, -, / and \.
1795
1796 Features are:
1797
1798 - Intersecting: When a `|' intersects with a `-', a `+' is
1799 drawn, like this: | \ /
1800 --+-- X
1801 | / \
1802
1803 - Rubber-banding: When drawing lines you can interactively see the
1804 result while holding the mouse button down and moving the mouse. If
1805 your machine is not fast enough (a 386 is a bit too slow, but a
1806 pentium is well enough), you can turn this feature off. You will
1807 then see 1's and 2's which mark the 1st and 2nd endpoint of the line
1808 you are drawing.
1809
1810 - Arrows: After having drawn a (straight) line or a (straight)
1811 poly-line, you can set arrows on the line-ends by typing < or >.
1812
1813 - Flood-filling: You can fill any area with a certain character by
1814 flood-filling.
1815
1816 - Cut copy and paste: You can cut, copy and paste rectangular
1817 regions. Artist also interfaces with the rect package (this can be
1818 turned off if it causes you any trouble) so anything you cut in
1819 artist can be yanked with C-x r y and vice versa.
1820
1821 - Drawing with keys: Everything you can do with the mouse, you can
1822 also do without the mouse.
1823
1824 - Aspect-ratio: You can set the variable artist-aspect-ratio to
1825 reflect the height-width ratio for the font you are using. Squares
1826 and circles are then drawn square/round. Note, that once your
1827 ascii-file is shown with font with a different height-width ratio,
1828 the squares won't be square and the circles won't be round.
1829
1830 - Drawing operations: The following drawing operations are implemented:
1831
1832 lines straight-lines
1833 rectangles squares
1834 poly-lines straight poly-lines
1835 ellipses circles
1836 text (see-thru) text (overwrite)
1837 spray-can setting size for spraying
1838 vaporize line vaporize lines
1839 erase characters erase rectangles
1840
1841 Straight lines are lines that go horizontally, vertically or
1842 diagonally. Plain lines go in any direction. The operations in
1843 the right column are accessed by holding down the shift key while
1844 drawing.
1845
1846 It is possible to vaporize (erase) entire lines and connected lines
1847 (rectangles for example) as long as the lines being vaporized are
1848 straight and connected at their endpoints. Vaporizing is inspired
1849 by the drawrect package by Jari Aalto <jari.aalto@poboxes.com>.
1850
1851 - Picture mode compatibility: Artist is picture mode compatible (this
1852 can be turned off).
1853
1854 *** The new package Eshell is an operating system command shell
1855 implemented entirely in Emacs Lisp. Use `M-x eshell' to invoke it.
1856 It functions similarly to bash and zsh, and allows running of Lisp
1857 functions and external commands using the same syntax. It supports
1858 history lists, aliases, extended globbing, smart scrolling, etc. It
1859 will work on any platform Emacs has been ported to. And since most of
1860 the basic commands -- ls, rm, mv, cp, ln, du, cat, etc. -- have been
1861 rewritten in Lisp, it offers an operating-system independent shell,
1862 all within the scope of your Emacs process.
1863
1864 *** The new package timeclock.el is a mode is for keeping track of time
1865 intervals. You can use it for whatever purpose you like, but the
1866 typical scenario is to keep track of how much time you spend working
1867 on certain projects.
1868
1869 *** The new package hi-lock.el provides commands to highlight matches
1870 of interactively entered regexps. For example,
1871
1872 M-x highlight-regexp RET clearly RET RET
1873
1874 will highlight all occurrences of `clearly' using a yellow background
1875 face. New occurrences of `clearly' will be highlighted as they are
1876 typed. `M-x unhighlight-regexp RET' will remove the highlighting.
1877 Any existing face can be used for highlighting and a set of
1878 appropriate faces is provided. The regexps can be written into the
1879 current buffer in a form that will be recognized the next time the
1880 corresponding file is read. There are commands to highlight matches
1881 to phrases and to highlight entire lines containing a match.
1882
1883 *** The new package zone.el plays games with Emacs' display when
1884 Emacs is idle.
1885
1886 *** The new package tildify.el allows to add hard spaces or other text
1887 fragments in accordance with the current major mode.
1888
1889 *** The new package xml.el provides a simple but generic XML
1890 parser. It doesn't parse the DTDs however.
1891
1892 *** The comment operations are now provided by the newcomment.el
1893 package which allows different styles of comment-region and should
1894 be more robust while offering the same functionality.
1895 `comment-region' now doesn't always comment a-line-at-a-time, but only
1896 comments the region, breaking the line at point if necessary.
1897
1898 *** The Ebrowse package implements a C++ class browser and tags
1899 facilities tailored for use with C++. It is documented in a
1900 separate Texinfo file.
1901
1902 *** The PCL-CVS package available by either running M-x cvs-examine or
1903 by visiting a CVS administrative directory (with a prefix argument)
1904 provides an alternative interface to VC-dired for CVS. It comes with
1905 `log-view-mode' to view RCS and SCCS logs and `log-edit-mode' used to
1906 enter check-in log messages.
1907
1908 *** The new package called `woman' allows to browse Unix man pages
1909 without invoking external programs.
1910
1911 The command `M-x woman' formats manual pages entirely in Emacs Lisp
1912 and then displays them, like `M-x manual-entry' does. Unlike
1913 `manual-entry', `woman' does not invoke any external programs, so it
1914 is useful on systems such as MS-DOS/MS-Windows where the `man' and
1915 Groff or `troff' commands are not readily available.
1916
1917 The command `M-x woman-find-file' asks for the file name of a man
1918 page, then formats and displays it like `M-x woman' does.
1919
1920 *** The new command M-x re-builder offers a convenient interface for
1921 authoring regular expressions with immediate visual feedback.
1922
1923 The buffer from which the command was called becomes the target for
1924 the regexp editor popping up in a separate window. Matching text in
1925 the target buffer is immediately color marked during the editing.
1926 Each sub-expression of the regexp will show up in a different face so
1927 even complex regexps can be edited and verified on target data in a
1928 single step.
1929
1930 On displays not supporting faces the matches instead blink like
1931 matching parens to make them stand out. On such a setup you will
1932 probably also want to use the sub-expression mode when the regexp
1933 contains such to get feedback about their respective limits.
1934
1935 *** glasses-mode is a minor mode that makes
1936 unreadableIdentifiersLikeThis readable. It works as glasses, without
1937 actually modifying content of a buffer.
1938
1939 *** The package ebnf2ps translates an EBNF to a syntactic chart in
1940 PostScript.
1941
1942 Currently accepts ad-hoc EBNF, ISO EBNF and Bison/Yacc.
1943
1944 The ad-hoc default EBNF syntax has the following elements:
1945
1946 ; comment (until end of line)
1947 A non-terminal
1948 "C" terminal
1949 ?C? special
1950 $A default non-terminal
1951 $"C" default terminal
1952 $?C? default special
1953 A = B. production (A is the header and B the body)
1954 C D sequence (C occurs before D)
1955 C | D alternative (C or D occurs)
1956 A - B exception (A excluding B, B without any non-terminal)
1957 n * A repetition (A repeats n (integer) times)
1958 (C) group (expression C is grouped together)
1959 [C] optional (C may or not occurs)
1960 C+ one or more occurrences of C
1961 {C}+ one or more occurrences of C
1962 {C}* zero or more occurrences of C
1963 {C} zero or more occurrences of C
1964 C / D equivalent to: C {D C}*
1965 {C || D}+ equivalent to: C {D C}*
1966 {C || D}* equivalent to: [C {D C}*]
1967 {C || D} equivalent to: [C {D C}*]
1968
1969 Please, see ebnf2ps documentation for EBNF syntax and how to use it.
1970
1971 *** The package align.el will align columns within a region, using M-x
1972 align. Its mode-specific rules, based on regular expressions,
1973 determine where the columns should be split. In C and C++, for
1974 example, it will align variable names in declaration lists, or the
1975 equal signs of assignments.
1976
1977 *** `paragraph-indent-minor-mode' is a new minor mode supporting
1978 paragraphs in the same style as `paragraph-indent-text-mode'.
1979
1980 *** bs.el is a new package for buffer selection similar to
1981 list-buffers or electric-buffer-list. Use M-x bs-show to display a
1982 buffer menu with this package. See the Custom group `bs'.
1983
1984 *** find-lisp.el is a package emulating the Unix find command in Lisp.
1985
1986 *** calculator.el is a small calculator package that is intended to
1987 replace desktop calculators such as xcalc and calc.exe. Actually, it
1988 is not too small - it has more features than most desktop calculators,
1989 and can be customized easily to get many more functions. It should
1990 not be confused with "calc" which is a much bigger mathematical tool
1991 which answers different needs.
1992
1993 *** The minor modes cwarn-mode and global-cwarn-mode highlights
1994 suspicious C and C++ constructions. Currently, assignments inside
1995 expressions, semicolon following `if', `for' and `while' (except, of
1996 course, after a `do .. while' statement), and C++ functions with
1997 reference parameters are recognized. The modes require font-lock mode
1998 to be enabled.
1999
2000 *** smerge-mode.el provides `smerge-mode', a simple minor-mode for files
2001 containing diff3-style conflict markers, such as generated by RCS.
2002
2003 *** 5x5.el is a simple puzzle game.
2004
2005 *** hl-line.el provides `hl-line-mode', a minor mode to highlight the
2006 current line in the current buffer. It also provides
2007 `global-hl-line-mode' to provide the same behaviour in all buffers.
2008
2009 *** ansi-color.el translates ANSI terminal escapes into text-properties.
2010
2011 Please note: if `ansi-color-for-comint-mode' and
2012 `global-font-lock-mode' are non-nil, loading ansi-color.el will
2013 disable font-lock and add `ansi-color-apply' to
2014 `comint-preoutput-filter-functions' for all shell-mode buffers. This
2015 displays the output of "ls --color=yes" using the correct foreground
2016 and background colors.
2017
2018 *** delphi.el provides a major mode for editing the Delphi (Object
2019 Pascal) language.
2020
2021 *** quickurl.el provides a simple method of inserting a URL based on
2022 the text at point.
2023
2024 *** sql.el provides an interface to SQL data bases.
2025
2026 *** fortune.el uses the fortune program to create mail/news signatures.
2027
2028 *** whitespace.el is a package for warning about and cleaning bogus
2029 whitespace in a file.
2030
2031 *** PostScript mode (ps-mode) is a new major mode for editing PostScript
2032 files. It offers: interaction with a PostScript interpreter, including
2033 (very basic) error handling; fontification, easily customizable for
2034 interpreter messages; auto-indentation; insertion of EPSF templates and
2035 often used code snippets; viewing of BoundingBox; commenting out /
2036 uncommenting regions; conversion of 8bit characters to PostScript octal
2037 codes. All functionality is accessible through a menu.
2038
2039 *** delim-col helps to prettify columns in a text region or rectangle.
2040
2041 Here is an example of columns:
2042
2043 horse apple bus
2044 dog pineapple car EXTRA
2045 porcupine strawberry airplane
2046
2047 Doing the following settings:
2048
2049 (setq delimit-columns-str-before "[ ")
2050 (setq delimit-columns-str-after " ]")
2051 (setq delimit-columns-str-separator ", ")
2052 (setq delimit-columns-separator "\t")
2053
2054
2055 Selecting the lines above and typing:
2056
2057 M-x delimit-columns-region
2058
2059 It results:
2060
2061 [ horse , apple , bus , ]
2062 [ dog , pineapple , car , EXTRA ]
2063 [ porcupine, strawberry, airplane, ]
2064
2065 delim-col has the following options:
2066
2067 delimit-columns-str-before Specify a string to be inserted
2068 before all columns.
2069
2070 delimit-columns-str-separator Specify a string to be inserted
2071 between each column.
2072
2073 delimit-columns-str-after Specify a string to be inserted
2074 after all columns.
2075
2076 delimit-columns-separator Specify a regexp which separates
2077 each column.
2078
2079 delim-col has the following commands:
2080
2081 delimit-columns-region Prettify all columns in a text region.
2082 delimit-columns-rectangle Prettify all columns in a text rectangle.
2083
2084 *** Recentf mode maintains a menu for visiting files that were
2085 operated on recently. User option recentf-menu-filter specifies a
2086 menu filter function to change the menu appearance. For example, the
2087 recent file list can be displayed:
2088
2089 - organized by major modes, directories or user defined rules.
2090 - sorted by file paths, file names, ascending or descending.
2091 - showing paths relative to the current default-directory
2092
2093 The `recentf-filter-changer' menu filter function allows to
2094 dynamically change the menu appearance.
2095
2096 *** elide-head.el provides a mechanism for eliding boilerplate header
2097 text.
2098
2099 *** footnote.el provides `footnote-mode', a minor mode supporting use
2100 of footnotes. It is intended for use with Message mode, but isn't
2101 specific to Message mode.
2102
2103 *** diff-mode.el provides `diff-mode', a major mode for
2104 viewing/editing context diffs (patches). It is selected for files
2105 with extension `.diff', `.diffs', `.patch' and `.rej'.
2106
2107 *** EUDC, the Emacs Unified Directory Client, provides a common user
2108 interface to access directory servers using different directory
2109 protocols. It has a separate manual.
2110
2111 *** autoconf.el provides a major mode for editing configure.in files
2112 for Autoconf, selected automatically.
2113
2114 *** windmove.el provides moving between windows.
2115
2116 *** crm.el provides a facility to read multiple strings from the
2117 minibuffer with completion.
2118
2119 *** todo-mode.el provides management of TODO lists and integration
2120 with the diary features.
2121
2122 *** autoarg.el provides a feature reported from Twenex Emacs whereby
2123 numeric keys supply prefix args rather than self inserting.
2124
2125 *** The function `turn-off-auto-fill' unconditionally turns off Auto
2126 Fill mode.
2127
2128 *** pcomplete.el is a library that provides programmable completion
2129 facilities for Emacs, similar to what zsh and tcsh offer. The main
2130 difference is that completion functions are written in Lisp, meaning
2131 they can be profiled, debugged, etc.
2132
2133 *** antlr-mode is a new major mode for editing ANTLR grammar files.
2134 It is automatically turned on for files whose names have the extension
2135 `.g'.
2136
2137 ** Changes in sort.el
2138
2139 The function sort-numeric-fields interprets numbers starting with `0'
2140 as octal and numbers starting with `0x' or `0X' as hexadecimal. The
2141 new user-option sort-numeric-base can be used to specify a default
2142 numeric base.
2143
2144 ** Changes to Ange-ftp
2145
2146 *** Ange-ftp allows you to specify of a port number in remote file
2147 names cleanly. It is appended to the host name, separated by a hash
2148 sign, e.g. `/foo@bar.org#666:mumble'. (This syntax comes from EFS.)
2149
2150 *** If the new user-option `ange-ftp-try-passive-mode' is set, passive
2151 ftp mode will be used if the ftp client supports that.
2152
2153 *** Ange-ftp handles the output of the w32-style clients which
2154 output ^M at the end of lines.
2155
2156 ** The recommended way of using Iswitchb is via the new global minor
2157 mode `iswitchb-mode'.
2158
2159 ** Just loading the msb package doesn't switch on Msb mode anymore.
2160 If you have `(require 'msb)' in your .emacs, please replace it with
2161 `(msb-mode 1)'.
2162
2163 ** Flyspell mode has various new options. See the `flyspell' Custom
2164 group.
2165
2166 ** The user option `backward-delete-char-untabify-method' controls the
2167 behavior of `backward-delete-char-untabify'. The following values
2168 are recognized:
2169
2170 `untabify' -- turn a tab to many spaces, then delete one space;
2171 `hungry' -- delete all whitespace, both tabs and spaces;
2172 `all' -- delete all whitespace, including tabs, spaces and newlines;
2173 nil -- just delete one character.
2174
2175 Default value is `untabify'.
2176
2177 [This change was made in Emacs 20.3 but not mentioned then.]
2178
2179 ** In Cperl mode `cperl-invalid-face' should now be a normal face
2180 symbol, not double-quoted.
2181
2182 ** Some packages are declared obsolete, to be removed in a future
2183 version. They are: auto-show, c-mode, hilit19, hscroll, ooutline,
2184 profile, rnews, rnewspost, and sc. Their implementations have been
2185 moved to lisp/obsolete.
2186
2187 ** auto-compression mode is no longer enabled just by loading jka-compr.el.
2188 To control it, set `auto-compression-mode' via Custom or use the
2189 `auto-compression-mode' command.
2190
2191 ** `browse-url-gnome-moz' is a new option for
2192 `browse-url-browser-function', invoking Mozilla in GNOME, and
2193 `browse-url-kde' can be chosen for invoking the KDE browser.
2194
2195 ** The user-option `browse-url-new-window-p' has been renamed to
2196 `browse-url-new-window-flag'.
2197
2198 ** The functions `keep-lines', `flush-lines' and `how-many' now
2199 operate on the active region in Transient Mark mode.
2200
2201 ** `gnus-user-agent' is a new possibility for `mail-user-agent'. It
2202 is like `message-user-agent', but with all the Gnus paraphernalia.
2203
2204 ** The Strokes package has been updated. If your Emacs has XPM
2205 support, you can use it for pictographic editing. In Strokes mode,
2206 use C-mouse-2 to compose a complex stoke and insert it into the
2207 buffer. You can encode or decode a strokes buffer with new commands
2208 M-x strokes-encode-buffer and M-x strokes-decode-buffer. There is a
2209 new command M-x strokes-list-strokes.
2210
2211 ** Hexl contains a new command `hexl-insert-hex-string' which inserts
2212 a string of hexadecimal numbers read from the mini-buffer.
2213
2214 ** Hexl mode allows to insert non-ASCII characters.
2215
2216 The non-ASCII characters are encoded using the same encoding as the
2217 file you are visiting in Hexl mode.
2218
2219 ** Shell script mode changes.
2220
2221 Shell script mode (sh-script) can now indent scripts for shells
2222 derived from sh and rc. The indentation style is customizable, and
2223 sh-script can attempt to "learn" the current buffer's style.
2224
2225 ** Etags changes.
2226
2227 *** In DOS, etags looks for file.cgz if it cannot find file.c.
2228
2229 *** New option --ignore-case-regex is an alternative to --regex. It is now
2230 possible to bind a regexp to a language, by prepending the regexp with
2231 {lang}, where lang is one of the languages that `etags --help' prints out.
2232 This feature is useful especially for regex files, where each line contains
2233 a regular expression. The manual contains details.
2234
2235 *** In C and derived languages, etags creates tags for function
2236 declarations when given the --declarations option.
2237
2238 *** In C++, tags are created for "operator". The tags have the form
2239 "operator+", without spaces between the keyword and the operator.
2240
2241 *** You shouldn't generally need any more the -C or -c++ option: etags
2242 automatically switches to C++ parsing when it meets the `class' or
2243 `template' keywords.
2244
2245 *** Etags now is able to delve at arbitrary deeps into nested structures in
2246 C-like languages. Previously, it was limited to one or two brace levels.
2247
2248 *** New language Ada: tags are functions, procedures, packages, tasks, and
2249 types.
2250
2251 *** In Fortran, `procedure' is not tagged.
2252
2253 *** In Java, tags are created for "interface".
2254
2255 *** In Lisp, "(defstruct (foo", "(defun (operator" and similar constructs
2256 are now tagged.
2257
2258 *** In makefiles, tags the targets.
2259
2260 *** In Perl, the --globals option tags global variables. my and local
2261 variables are tagged.
2262
2263 *** New language Python: def and class at the beginning of a line are tags.
2264
2265 *** .ss files are Scheme files, .pdb is Postscript with C syntax, .psw is
2266 for PSWrap.
2267
2268 ** Changes in etags.el
2269
2270 *** The new user-option tags-case-fold-search can be used to make
2271 tags operations case-sensitive or case-insensitive. The default
2272 is to use the same setting as case-fold-search.
2273
2274 *** You can display additional output with M-x tags-apropos by setting
2275 the new variable tags-apropos-additional-actions.
2276
2277 If non-nil, the variable's value should be a list of triples (TITLE
2278 FUNCTION TO-SEARCH). For each triple, M-x tags-apropos processes
2279 TO-SEARCH and lists tags from it. TO-SEARCH should be an alist,
2280 obarray, or symbol. If it is a symbol, the symbol's value is used.
2281
2282 TITLE is a string to use to label the list of tags from TO-SEARCH.
2283
2284 FUNCTION is a function to call when an entry is selected in the Tags
2285 List buffer. It is called with one argument, the selected symbol.
2286
2287 A useful example value for this variable might be something like:
2288
2289 '(("Emacs Lisp" Info-goto-emacs-command-node obarray)
2290 ("Common Lisp" common-lisp-hyperspec common-lisp-hyperspec-obarray)
2291 ("SCWM" scwm-documentation scwm-obarray))
2292
2293 *** The face tags-tag-face can be used to customize the appearance
2294 of tags in the output of M-x tags-apropos.
2295
2296 *** Setting tags-apropos-verbose to a non-nil value displays the
2297 names of tags files in the *Tags List* buffer.
2298
2299 *** You can now search for tags that are part of the filename itself.
2300 If you have tagged the files topfile.c subdir/subfile.c
2301 /tmp/tempfile.c, you can now search for tags "topfile.c", "subfile.c",
2302 "dir/sub", "tempfile", "tempfile.c". If the tag matches the file name,
2303 point will go to the beginning of the file.
2304
2305 *** Compressed files are now transparently supported if
2306 auto-compression-mode is active. You can tag (with Etags) and search
2307 (with find-tag) both compressed and uncompressed files.
2308
2309 *** Tags commands like M-x tags-search no longer change point
2310 in buffers where no match is found. In buffers where a match is
2311 found, the original value of point is pushed on the marker ring.
2312
2313 ** Fortran mode has a new command `fortran-strip-sequence-nos' to
2314 remove text past column 72. The syntax class of `\' in Fortran is now
2315 appropriate for C-style escape sequences in strings.
2316
2317 ** SGML mode's default `sgml-validate-command' is now `nsgmls'.
2318
2319 ** A new command `view-emacs-problems' (C-h P) displays the PROBLEMS file.
2320
2321 ** The Dabbrev package has a new user-option `dabbrev-ignored-regexps'
2322 containing a list of regular expressions. Buffers matching a regular
2323 expression from that list, are not checked.
2324
2325 ** Emacs can now figure out modification times of remote files.
2326 When you do C-x C-f /user@host:/path/file RET and edit the file,
2327 and someone else modifies the file, you will be prompted to revert
2328 the buffer, just like for the local files.
2329
2330 ** The buffer menu (C-x C-b) no longer lists the *Buffer List* buffer.
2331
2332 ** When invoked with a prefix argument, the command `list-abbrevs' now
2333 displays local abbrevs, only.
2334
2335 ** Refill minor mode provides preliminary support for keeping
2336 paragraphs filled as you modify them.
2337
2338 ** The variable `double-click-fuzz' specifies how much the mouse
2339 may be moved between clicks that are recognized as a pair. Its value
2340 is measured in pixels.
2341
2342 ** The new global minor mode `auto-image-file-mode' allows image files
2343 to be visited as images.
2344
2345 ** Two new user-options `grep-command' and `grep-find-command'
2346 were added to compile.el.
2347
2348 ** Withdrawn packages
2349
2350 *** mldrag.el has been removed. mouse.el provides the same
2351 functionality with aliases for the mldrag functions.
2352
2353 *** eval-reg.el has been obsoleted by changes to edebug.el and removed.
2354
2355 *** ph.el has been obsoleted by EUDC and removed.
2356
2357 \f
2358 * Incompatible Lisp changes
2359
2360 There are a few Lisp changes which are not backwards-compatible and
2361 may require changes to existing code. Here is a list for reference.
2362 See the sections below for details.
2363
2364 ** Since `format' preserves text properties, the idiom
2365 `(format "%s" foo)' no longer works to copy and remove properties.
2366 Use `copy-sequence' and `set-text-properties'.
2367
2368 ** Since the `keymap' text property now has significance, some code
2369 which uses both `local-map' and `keymap' properties (for portability)
2370 may, for instance, give rise to duplicate menus when the keymaps from
2371 these properties are active.
2372
2373 ** The change in the treatment of non-ASCII characters in search
2374 ranges may affect some code.
2375
2376 ** A non-nil value for the LOCAL arg of add-hook makes the hook
2377 buffer-local even if `make-local-hook' hasn't been called, which might
2378 make a difference to some code.
2379
2380 ** The new treatment of the minibuffer prompt might affect code which
2381 operates on the minibuffer.
2382
2383 ** The new character sets `eight-bit-control' and `eight-bit-graphic'
2384 cause `no-conversion' and `emacs-mule-unix' coding systems to produce
2385 different results when reading files with non-ASCII characters
2386 (previously, both coding systems would produce the same results).
2387 Specifically, `no-conversion' interprets each 8-bit byte as a separate
2388 character. This makes `no-conversion' inappropriate for reading
2389 multibyte text, e.g. buffers written to disk in their internal MULE
2390 encoding (auto-saving does that, for example). If a Lisp program
2391 reads such files with `no-conversion', each byte of the multibyte
2392 sequence, including the MULE leading codes such as \201, is treated as
2393 a separate character, which prevents them from being interpreted in
2394 the buffer as multibyte characters.
2395
2396 Therefore, Lisp programs that read files which contain the internal
2397 MULE encoding should use `emacs-mule-unix'. `no-conversion' is only
2398 appropriate for reading truly binary files.
2399
2400 ** Code that relies on the obsolete `before-change-function' and
2401 `after-change-function' to detect buffer changes will now fail. Use
2402 `before-change-functions' and `after-change-functions' instead.
2403
2404 ** Code that uses `concat' with integer args now gets an error, as
2405 long promised.
2406
2407 ** The function base64-decode-string now always returns a unibyte
2408 string.
2409
2410 ** Not a Lisp incompatibility as such but, with the introduction of
2411 extra private charsets, there is now only one slot free for a new
2412 dimension-2 private charset. User code which tries to add more than
2413 one extra will fail unless you rebuild Emacs with some standard
2414 charset(s) removed; that is probably inadvisable because it changes
2415 the emacs-mule encoding. Also, files stored in the emacs-mule
2416 encoding using Emacs 20 with additional private charsets defined will
2417 probably not be read correctly by Emacs 21.
2418
2419 ** The variable `directory-sep-char' is slated for removal.
2420 Not really a change (yet), but a projected one that you should be
2421 aware of: The variable `directory-sep-char' is deprecated, and should
2422 not be used. It was always ignored on GNU/Linux and Unix systems and
2423 on MS-DOS, but the MS-Windows port tried to support it by adapting the
2424 behavior of certain primitives to the value of this variable. It
2425 turned out that such support cannot be reliable, so it was decided to
2426 remove this variable in the near future. Lisp programs are well
2427 advised not to set it to anything but '/', because any different value
2428 will not have any effect when support for this variable is removed.
2429
2430 \f
2431 * Lisp changes made after edition 2.6 of the Emacs Lisp Manual,
2432 (Display-related features are described in a page of their own below.)
2433
2434 ** Function assq-delete-all replaces function assoc-delete-all.
2435
2436 ** The new function amimate-string, from lisp/play/animate.el
2437 allows the animated display of strings.
2438
2439 ** The new function `interactive-form' can be used to obtain the
2440 interactive form of a function.
2441
2442 ** The keyword :set-after in defcustom allows to specify dependencies
2443 between custom options. Example:
2444
2445 (defcustom default-input-method nil
2446 "*Default input method for multilingual text (a string).
2447 This is the input method activated automatically by the command
2448 `toggle-input-method' (\\[toggle-input-method])."
2449 :group 'mule
2450 :type '(choice (const nil) string)
2451 :set-after '(current-language-environment))
2452
2453 This specifies that default-input-method should be set after
2454 current-language-environment even if default-input-method appears
2455 first in a custom-set-variables statement.
2456
2457 ** The new hook `kbd-macro-termination-hook' is run at the end of
2458 function execute-kbd-macro. Functions on this hook are called with no
2459 args. The hook is run independent of how the macro was terminated
2460 (signal or normal termination).
2461
2462 ** Functions `butlast' and `nbutlast' for removing trailing elements
2463 from a list are now available without requiring the CL package.
2464
2465 ** The new user-option `even-window-heights' can be set to nil
2466 to prevent `display-buffer' from evening out window heights.
2467
2468 ** The user-option `face-font-registry-alternatives' specifies
2469 alternative font registry names to try when looking for a font.
2470
2471 ** Function `md5' calculates the MD5 "message digest"/"checksum".
2472
2473 ** Function `delete-frame' runs `delete-frame-hook' before actually
2474 deleting the frame. The hook is called with one arg, the frame
2475 being deleted.
2476
2477 ** `add-hook' now makes the hook local if called with a non-nil LOCAL arg.
2478
2479 ** The treatment of non-ASCII characters in search ranges has changed.
2480 If a range in a regular expression or the arg of
2481 skip-chars-forward/backward starts with a unibyte character C and ends
2482 with a multibyte character C2, the range is divided into two: one is
2483 C..?\377, the other is C1..C2, where C1 is the first character of C2's
2484 charset.
2485
2486 ** The new function `display-message-or-buffer' displays a message in
2487 the echo area or pops up a buffer, depending on the length of the
2488 message.
2489
2490 ** The new macro `with-auto-compression-mode' allows evaluating an
2491 expression with auto-compression-mode enabled.
2492
2493 ** In image specifications, `:heuristic-mask' has been replaced
2494 with the more general `:mask' property.
2495
2496 ** Image specifications accept more `:conversion's.
2497
2498 ** A `?' can be used in a symbol name without escaping it with a
2499 backslash.
2500
2501 ** Reading from the mini-buffer now reads from standard input if Emacs
2502 is running in batch mode. For example,
2503
2504 (message "%s" (read t))
2505
2506 will read a Lisp expression from standard input and print the result
2507 to standard output.
2508
2509 ** The argument of `down-list', `backward-up-list', `up-list',
2510 `kill-sexp', `backward-kill-sexp' and `mark-sexp' is now optional.
2511
2512 ** If `display-buffer-reuse-frames' is set, function `display-buffer'
2513 will raise frames displaying a buffer, instead of creating a new
2514 frame or window.
2515
2516 ** Two new functions for removing elements from lists/sequences
2517 were added
2518
2519 - Function: remove ELT SEQ
2520
2521 Return a copy of SEQ with all occurrences of ELT removed. SEQ must be
2522 a list, vector, or string. The comparison is done with `equal'.
2523
2524 - Function: remq ELT LIST
2525
2526 Return a copy of LIST with all occurrences of ELT removed. The
2527 comparison is done with `eq'.
2528
2529 ** The function `delete' now also works with vectors and strings.
2530
2531 ** The meaning of the `:weakness WEAK' argument of make-hash-table
2532 has been changed: WEAK can now have new values `key-or-value' and
2533 `key-and-value', in addition the `nil', `key', `value', and `t'.
2534
2535 ** Function `aset' stores any multibyte character in any string
2536 without signaling "Attempt to change char length of a string". It may
2537 convert a unibyte string to multibyte if necessary.
2538
2539 ** The value of the `help-echo' text property is called as a function
2540 or evaluated, if it is not a string already, to obtain a help string.
2541
2542 ** Function `make-obsolete' now has an optional arg to say when the
2543 function was declared obsolete.
2544
2545 ** Function `plist-member' is renamed from `widget-plist-member' (which is
2546 retained as an alias).
2547
2548 ** Easy-menu's :filter now works as in XEmacs.
2549 It takes the unconverted (i.e. XEmacs) form of the menu and the result
2550 is automatically converted to Emacs' form.
2551
2552 ** The new function `window-list' has been defined
2553
2554 - Function: window-list &optional FRAME WINDOW MINIBUF
2555
2556 Return a list of windows on FRAME, starting with WINDOW. FRAME nil or
2557 omitted means use the selected frame. WINDOW nil or omitted means use
2558 the selected window. MINIBUF t means include the minibuffer window,
2559 even if it isn't active. MINIBUF nil or omitted means include the
2560 minibuffer window only if it's active. MINIBUF neither nil nor t
2561 means never include the minibuffer window.
2562
2563 ** There's a new function `get-window-with-predicate' defined as follows
2564
2565 - Function: get-window-with-predicate PREDICATE &optional MINIBUF ALL-FRAMES DEFAULT
2566
2567 Return a window satisfying PREDICATE.
2568
2569 This function cycles through all visible windows using `walk-windows',
2570 calling PREDICATE on each one. PREDICATE is called with a window as
2571 argument. The first window for which PREDICATE returns a non-nil
2572 value is returned. If no window satisfies PREDICATE, DEFAULT is
2573 returned.
2574
2575 Optional second arg MINIBUF t means count the minibuffer window even
2576 if not active. MINIBUF nil or omitted means count the minibuffer iff
2577 it is active. MINIBUF neither t nor nil means not to count the
2578 minibuffer even if it is active.
2579
2580 Several frames may share a single minibuffer; if the minibuffer
2581 counts, all windows on all frames that share that minibuffer count
2582 too. Therefore, if you are using a separate minibuffer frame
2583 and the minibuffer is active and MINIBUF says it counts,
2584 `walk-windows' includes the windows in the frame from which you
2585 entered the minibuffer, as well as the minibuffer window.
2586
2587 ALL-FRAMES is the optional third argument.
2588 ALL-FRAMES nil or omitted means cycle within the frames as specified above.
2589 ALL-FRAMES = `visible' means include windows on all visible frames.
2590 ALL-FRAMES = 0 means include windows on all visible and iconified frames.
2591 ALL-FRAMES = t means include windows on all frames including invisible frames.
2592 If ALL-FRAMES is a frame, it means include windows on that frame.
2593 Anything else means restrict to the selected frame.
2594
2595 ** The function `single-key-description' now encloses function key and
2596 event names in angle brackets. When called with a second optional
2597 argument non-nil, angle brackets won't be printed.
2598
2599 ** If the variable `message-truncate-lines' is bound to t around a
2600 call to `message', the echo area will not be resized to display that
2601 message; it will be truncated instead, as it was done in 20.x.
2602 Default value is nil.
2603
2604 ** The user option `line-number-display-limit' can now be set to nil,
2605 meaning no limit.
2606
2607 ** The new user option `line-number-display-limit-width' controls
2608 the maximum width of lines in a buffer for which Emacs displays line
2609 numbers in the mode line. The default is 200.
2610
2611 ** `select-safe-coding-system' now also checks the most preferred
2612 coding-system if buffer-file-coding-system is `undecided' and
2613 DEFAULT-CODING-SYSTEM is not specified,
2614
2615 ** The function `subr-arity' provides information about the argument
2616 list of a primitive.
2617
2618 ** `where-is-internal' now also accepts a list of keymaps.
2619
2620 ** The text property `keymap' specifies a key map which overrides the
2621 buffer's local map and the map specified by the `local-map' property.
2622 This is probably what most current uses of `local-map' want, rather
2623 than replacing the local map.
2624
2625 ** The obsolete variables `before-change-function' and
2626 `after-change-function' are no longer acted upon and have been
2627 removed. Use `before-change-functions' and `after-change-functions'
2628 instead.
2629
2630 ** The function `apropos-mode' runs the hook `apropos-mode-hook'.
2631
2632 ** `concat' no longer accepts individual integer arguments,
2633 as promised long ago.
2634
2635 ** The new function `float-time' returns the current time as a float.
2636
2637 ** The new variable auto-coding-regexp-alist specifies coding systems
2638 for reading specific files, analogous to auto-coding-alist, but
2639 patterns are checked against file contents instead of file names.
2640
2641 \f
2642 * Lisp changes in Emacs 21.1 (see following page for display-related features)
2643
2644 Note that +++ before an item means the Lisp manual has been updated.
2645 --- means that I have decided it does not need to be in the Lisp manual.
2646 When you add a new item, please add it without either +++ or ---
2647 so I will know I still need to look at it -- rms.
2648
2649 ** The new package rx.el provides an alternative sexp notation for
2650 regular expressions.
2651
2652 - Function: rx-to-string SEXP
2653
2654 Translate SEXP into a regular expression in string notation.
2655
2656 - Macro: rx SEXP
2657
2658 Translate SEXP into a regular expression in string notation.
2659
2660 The following are valid subforms of regular expressions in sexp
2661 notation.
2662
2663 STRING
2664 matches string STRING literally.
2665
2666 CHAR
2667 matches character CHAR literally.
2668
2669 `not-newline'
2670 matches any character except a newline.
2671 .
2672 `anything'
2673 matches any character
2674
2675 `(any SET)'
2676 matches any character in SET. SET may be a character or string.
2677 Ranges of characters can be specified as `A-Z' in strings.
2678
2679 '(in SET)'
2680 like `any'.
2681
2682 `(not (any SET))'
2683 matches any character not in SET
2684
2685 `line-start'
2686 matches the empty string, but only at the beginning of a line
2687 in the text being matched
2688
2689 `line-end'
2690 is similar to `line-start' but matches only at the end of a line
2691
2692 `string-start'
2693 matches the empty string, but only at the beginning of the
2694 string being matched against.
2695
2696 `string-end'
2697 matches the empty string, but only at the end of the
2698 string being matched against.
2699
2700 `buffer-start'
2701 matches the empty string, but only at the beginning of the
2702 buffer being matched against.
2703
2704 `buffer-end'
2705 matches the empty string, but only at the end of the
2706 buffer being matched against.
2707
2708 `point'
2709 matches the empty string, but only at point.
2710
2711 `word-start'
2712 matches the empty string, but only at the beginning or end of a
2713 word.
2714
2715 `word-end'
2716 matches the empty string, but only at the end of a word.
2717
2718 `word-boundary'
2719 matches the empty string, but only at the beginning or end of a
2720 word.
2721
2722 `(not word-boundary)'
2723 matches the empty string, but not at the beginning or end of a
2724 word.
2725
2726 `digit'
2727 matches 0 through 9.
2728
2729 `control'
2730 matches ASCII control characters.
2731
2732 `hex-digit'
2733 matches 0 through 9, a through f and A through F.
2734
2735 `blank'
2736 matches space and tab only.
2737
2738 `graphic'
2739 matches graphic characters--everything except ASCII control chars,
2740 space, and DEL.
2741
2742 `printing'
2743 matches printing characters--everything except ASCII control chars
2744 and DEL.
2745
2746 `alphanumeric'
2747 matches letters and digits. (But at present, for multibyte characters,
2748 it matches anything that has word syntax.)
2749
2750 `letter'
2751 matches letters. (But at present, for multibyte characters,
2752 it matches anything that has word syntax.)
2753
2754 `ascii'
2755 matches ASCII (unibyte) characters.
2756
2757 `nonascii'
2758 matches non-ASCII (multibyte) characters.
2759
2760 `lower'
2761 matches anything lower-case.
2762
2763 `upper'
2764 matches anything upper-case.
2765
2766 `punctuation'
2767 matches punctuation. (But at present, for multibyte characters,
2768 it matches anything that has non-word syntax.)
2769
2770 `space'
2771 matches anything that has whitespace syntax.
2772
2773 `word'
2774 matches anything that has word syntax.
2775
2776 `(syntax SYNTAX)'
2777 matches a character with syntax SYNTAX. SYNTAX must be one
2778 of the following symbols.
2779
2780 `whitespace' (\\s- in string notation)
2781 `punctuation' (\\s.)
2782 `word' (\\sw)
2783 `symbol' (\\s_)
2784 `open-parenthesis' (\\s()
2785 `close-parenthesis' (\\s))
2786 `expression-prefix' (\\s')
2787 `string-quote' (\\s\")
2788 `paired-delimiter' (\\s$)
2789 `escape' (\\s\\)
2790 `character-quote' (\\s/)
2791 `comment-start' (\\s<)
2792 `comment-end' (\\s>)
2793
2794 `(not (syntax SYNTAX))'
2795 matches a character that has not syntax SYNTAX.
2796
2797 `(category CATEGORY)'
2798 matches a character with category CATEGORY. CATEGORY must be
2799 either a character to use for C, or one of the following symbols.
2800
2801 `consonant' (\\c0 in string notation)
2802 `base-vowel' (\\c1)
2803 `upper-diacritical-mark' (\\c2)
2804 `lower-diacritical-mark' (\\c3)
2805 `tone-mark' (\\c4)
2806 `symbol' (\\c5)
2807 `digit' (\\c6)
2808 `vowel-modifying-diacritical-mark' (\\c7)
2809 `vowel-sign' (\\c8)
2810 `semivowel-lower' (\\c9)
2811 `not-at-end-of-line' (\\c<)
2812 `not-at-beginning-of-line' (\\c>)
2813 `alpha-numeric-two-byte' (\\cA)
2814 `chinse-two-byte' (\\cC)
2815 `greek-two-byte' (\\cG)
2816 `japanese-hiragana-two-byte' (\\cH)
2817 `indian-tow-byte' (\\cI)
2818 `japanese-katakana-two-byte' (\\cK)
2819 `korean-hangul-two-byte' (\\cN)
2820 `cyrillic-two-byte' (\\cY)
2821 `ascii' (\\ca)
2822 `arabic' (\\cb)
2823 `chinese' (\\cc)
2824 `ethiopic' (\\ce)
2825 `greek' (\\cg)
2826 `korean' (\\ch)
2827 `indian' (\\ci)
2828 `japanese' (\\cj)
2829 `japanese-katakana' (\\ck)
2830 `latin' (\\cl)
2831 `lao' (\\co)
2832 `tibetan' (\\cq)
2833 `japanese-roman' (\\cr)
2834 `thai' (\\ct)
2835 `vietnamese' (\\cv)
2836 `hebrew' (\\cw)
2837 `cyrillic' (\\cy)
2838 `can-break' (\\c|)
2839
2840 `(not (category CATEGORY))'
2841 matches a character that has not category CATEGORY.
2842
2843 `(and SEXP1 SEXP2 ...)'
2844 matches what SEXP1 matches, followed by what SEXP2 matches, etc.
2845
2846 `(submatch SEXP1 SEXP2 ...)'
2847 like `and', but makes the match accessible with `match-end',
2848 `match-beginning', and `match-string'.
2849
2850 `(group SEXP1 SEXP2 ...)'
2851 another name for `submatch'.
2852
2853 `(or SEXP1 SEXP2 ...)'
2854 matches anything that matches SEXP1 or SEXP2, etc. If all
2855 args are strings, use `regexp-opt' to optimize the resulting
2856 regular expression.
2857
2858 `(minimal-match SEXP)'
2859 produce a non-greedy regexp for SEXP. Normally, regexps matching
2860 zero or more occurrances of something are \"greedy\" in that they
2861 match as much as they can, as long as the overall regexp can
2862 still match. A non-greedy regexp matches as little as possible.
2863
2864 `(maximal-match SEXP)'
2865 produce a greedy regexp for SEXP. This is the default.
2866
2867 `(zero-or-more SEXP)'
2868 matches zero or more occurrences of what SEXP matches.
2869
2870 `(0+ SEXP)'
2871 like `zero-or-more'.
2872
2873 `(* SEXP)'
2874 like `zero-or-more', but always produces a greedy regexp.
2875
2876 `(*? SEXP)'
2877 like `zero-or-more', but always produces a non-greedy regexp.
2878
2879 `(one-or-more SEXP)'
2880 matches one or more occurrences of A.
2881
2882 `(1+ SEXP)'
2883 like `one-or-more'.
2884
2885 `(+ SEXP)'
2886 like `one-or-more', but always produces a greedy regexp.
2887
2888 `(+? SEXP)'
2889 like `one-or-more', but always produces a non-greedy regexp.
2890
2891 `(zero-or-one SEXP)'
2892 matches zero or one occurrences of A.
2893
2894 `(optional SEXP)'
2895 like `zero-or-one'.
2896
2897 `(? SEXP)'
2898 like `zero-or-one', but always produces a greedy regexp.
2899
2900 `(?? SEXP)'
2901 like `zero-or-one', but always produces a non-greedy regexp.
2902
2903 `(repeat N SEXP)'
2904 matches N occurrences of what SEXP matches.
2905
2906 `(repeat N M SEXP)'
2907 matches N to M occurrences of what SEXP matches.
2908
2909 `(eval FORM)'
2910 evaluate FORM and insert result. If result is a string,
2911 `regexp-quote' it.
2912
2913 `(regexp REGEXP)'
2914 include REGEXP in string notation in the result.
2915
2916 *** The features `md5' and `overlay' are now provided by default.
2917
2918 *** The special form `save-restriction' now works correctly even if the
2919 buffer is widened inside the save-restriction and changes made outside
2920 the original restriction. Previously, doing this would cause the saved
2921 restriction to be restored incorrectly.
2922
2923 *** The functions `find-charset-region' and `find-charset-string' include
2924 `eight-bit-control' and/or `eight-bit-graphic' in the returned list
2925 when they find 8-bit characters. Previously, they included `ascii' in a
2926 multibyte buffer and `unknown' in a unibyte buffer.
2927
2928 *** The functions `set-buffer-multibyte', `string-as-multibyte' and
2929 `string-as-unibyte' change the byte sequence of a buffer or a string
2930 if it contains a character from the `eight-bit-control' character set.
2931
2932 *** The handling of multibyte sequences in a multibyte buffer is
2933 changed. Previously, a byte sequence matching the pattern
2934 [\200-\237][\240-\377]+ was interpreted as a single character
2935 regardless of the length of the trailing bytes [\240-\377]+. Thus, if
2936 the sequence was longer than what the leading byte indicated, the
2937 extra trailing bytes were ignored by Lisp functions. Now such extra
2938 bytes are independent 8-bit characters belonging to the charset
2939 eight-bit-graphic.
2940
2941 ** Fontsets are now implemented using char-tables.
2942
2943 A fontset can now be specified for each independent character, for
2944 a group of characters or for a character set rather than just for a
2945 character set as previously.
2946
2947 *** The arguments of the function `set-fontset-font' are changed.
2948 They are NAME, CHARACTER, FONTNAME, and optional FRAME. The function
2949 modifies fontset NAME to use FONTNAME for CHARACTER.
2950
2951 CHARACTER may be a cons (FROM . TO), where FROM and TO are non-generic
2952 characters. In that case FONTNAME is used for all characters in the
2953 range FROM and TO (inclusive). CHARACTER may be a charset. In that
2954 case FONTNAME is used for all character in the charset.
2955
2956 FONTNAME may be a cons (FAMILY . REGISTRY), where FAMILY is the family
2957 name of a font and REGISTRY is a registry name of a font.
2958
2959 *** Variable x-charset-registry has been deleted. The default charset
2960 registries of character sets are set in the default fontset
2961 "fontset-default".
2962
2963 *** The function `create-fontset-from-fontset-spec' ignores the second
2964 argument STYLE-VARIANT. It never creates style-variant fontsets.
2965
2966 ** The method of composing characters is changed. Now character
2967 composition is done by a special text property `composition' in
2968 buffers and strings.
2969
2970 *** Charset composition is deleted. Emacs never creates a `composite
2971 character' which is an independent character with a unique character
2972 code. Thus the following functions handling `composite characters'
2973 have been deleted: composite-char-component,
2974 composite-char-component-count, composite-char-composition-rule,
2975 composite-char-composition-rule and decompose-composite-char delete.
2976 The variables leading-code-composition and min-composite-char have
2977 also been deleted.
2978
2979 *** Three more glyph reference points are added. They can be used to
2980 specify a composition rule. See the documentation of the variable
2981 `reference-point-alist' for more detail.
2982
2983 *** The function `compose-region' takes new arguments COMPONENTS and
2984 MODIFICATION-FUNC. With COMPONENTS, you can specify not only a
2985 composition rule but also characters to be composed. Such characters
2986 may differ between buffer and string text.
2987
2988 *** The function `compose-string' takes new arguments START, END,
2989 COMPONENTS, and MODIFICATION-FUNC.
2990
2991 *** The function `compose-string' puts text property `composition'
2992 directly on the argument STRING instead of returning a new string.
2993 Likewise, the function `decompose-string' just removes text property
2994 `composition' from STRING.
2995
2996 *** The new function `find-composition' returns information about
2997 a composition at a specified position in a buffer or a string.
2998
2999 *** The function `decompose-composite-char' is now labeled as
3000 obsolete.
3001
3002 ** The new coding system `mac-roman' is primarily intended for use on
3003 the Macintosh but may be used generally for Macintosh-encoded text.
3004
3005 ** The new character sets `mule-unicode-0100-24ff',
3006 `mule-unicode-2500-33ff', and `mule-unicode-e000-ffff' have been
3007 introduced for Unicode characters in the range U+0100..U+24FF,
3008 U+2500..U+33FF, U+E000..U+FFFF respectively.
3009
3010 Note that the character sets are not yet unified in Emacs, so
3011 characters which belong to charsets such as Latin-2, Greek, Hebrew,
3012 etc. and the same characters in the `mule-unicode-*' charsets are
3013 different characters, as far as Emacs is concerned. For example, text
3014 which includes Unicode characters from the Latin-2 locale cannot be
3015 encoded by Emacs with ISO 8859-2 coding system.
3016
3017 ** The new coding system `mule-utf-8' has been added.
3018 It provides limited support for decoding/encoding UTF-8 text. For
3019 details, please see the documentation string of this coding system.
3020
3021 ** The new character sets `japanese-jisx0213-1' and
3022 `japanese-jisx0213-2' have been introduced for the new Japanese
3023 standard JIS X 0213 Plane 1 and Plane 2.
3024
3025 ** The new character sets `latin-iso8859-14' and `latin-iso8859-15'
3026 have been introduced.
3027
3028 ** The new character sets `eight-bit-control' and `eight-bit-graphic'
3029 have been introduced for 8-bit characters in the ranges 0x80..0x9F and
3030 0xA0..0xFF respectively. Note that the multibyte representation of
3031 eight-bit-control is never exposed; this leads to an exception in the
3032 emacs-mule coding system, which encodes everything else to the
3033 buffer/string internal representation. Note that to search for
3034 eight-bit-graphic characters in a multibyte buffer, the search string
3035 must be multibyte, otherwise such characters will be converted to
3036 their multibyte equivalent.
3037
3038 ** If the APPEND argument of `write-region' is an integer, it seeks to
3039 that offset in the file before writing.
3040
3041 ** The function `add-minor-mode' has been added for convenience and
3042 compatibility with XEmacs (and is used internally by define-minor-mode).
3043
3044 ** The function `shell-command' now sets the default directory of the
3045 `*Shell Command Output*' buffer to the default directory of the buffer
3046 from which the command was issued.
3047
3048 ** The functions `query-replace', `query-replace-regexp',
3049 `query-replace-regexp-eval' `map-query-replace-regexp',
3050 `replace-string', `replace-regexp', and `perform-replace' take two
3051 additional optional arguments START and END that specify the region to
3052 operate on.
3053
3054 ** The new function `count-screen-lines' is a more flexible alternative
3055 to `window-buffer-height'.
3056
3057 - Function: count-screen-lines &optional BEG END COUNT-FINAL-NEWLINE WINDOW
3058
3059 Return the number of screen lines in the region between BEG and END.
3060 The number of screen lines may be different from the number of actual
3061 lines, due to line breaking, display table, etc.
3062
3063 Optional arguments BEG and END default to `point-min' and `point-max'
3064 respectively.
3065
3066 If region ends with a newline, ignore it unless optional third argument
3067 COUNT-FINAL-NEWLINE is non-nil.
3068
3069 The optional fourth argument WINDOW specifies the window used for
3070 obtaining parameters such as width, horizontal scrolling, and so
3071 on. The default is to use the selected window's parameters.
3072
3073 Like `vertical-motion', `count-screen-lines' always uses the current
3074 buffer, regardless of which buffer is displayed in WINDOW. This makes
3075 possible to use `count-screen-lines' in any buffer, whether or not it
3076 is currently displayed in some window.
3077
3078 ** The new function `mapc' is like `mapcar' but doesn't collect the
3079 argument function's results.
3080
3081 ** The functions base64-decode-region and base64-decode-string now
3082 signal an error instead of returning nil if decoding fails. Also,
3083 `base64-decode-string' now always returns a unibyte string (in Emacs
3084 20, it returned a multibyte string when the result was a valid multibyte
3085 sequence).
3086
3087 ** The function sendmail-user-agent-compose now recognizes a `body'
3088 header in the list of headers passed to it.
3089
3090 ** The new function member-ignore-case works like `member', but
3091 ignores differences in case and text representation.
3092
3093 ** The buffer-local variable cursor-type can be used to specify the
3094 cursor to use in windows displaying a buffer. Values are interpreted
3095 as follows:
3096
3097 t use the cursor specified for the frame (default)
3098 nil don't display a cursor
3099 `bar' display a bar cursor with default width
3100 (bar . WIDTH) display a bar cursor with width WIDTH
3101 others display a box cursor.
3102
3103 ** The variable open-paren-in-column-0-is-defun-start controls whether
3104 an open parenthesis in column 0 is considered to be the start of a
3105 defun. If set, the default, it is considered a defun start. If not
3106 set, an open parenthesis in column 0 has no special meaning.
3107
3108 ** The new function `string-to-syntax' can be used to translate syntax
3109 specifications in string form as accepted by `modify-syntax-entry' to
3110 the cons-cell form that is used for the values of the `syntax-table'
3111 text property, and in `font-lock-syntactic-keywords'.
3112
3113 Example:
3114
3115 (string-to-syntax "()")
3116 => (4 . 41)
3117
3118 ** Emacs' reader supports CL read syntax for integers in bases
3119 other than 10.
3120
3121 *** `#BINTEGER' or `#bINTEGER' reads INTEGER in binary (radix 2).
3122 INTEGER optionally contains a sign.
3123
3124 #b1111
3125 => 15
3126 #b-1111
3127 => -15
3128
3129 *** `#OINTEGER' or `#oINTEGER' reads INTEGER in octal (radix 8).
3130
3131 #o666
3132 => 438
3133
3134 *** `#XINTEGER' or `#xINTEGER' reads INTEGER in hexadecimal (radix 16).
3135
3136 #xbeef
3137 => 48815
3138
3139 *** `#RADIXrINTEGER' reads INTEGER in radix RADIX, 2 <= RADIX <= 36.
3140
3141 #2R-111
3142 => -7
3143 #25rah
3144 => 267
3145
3146 ** The function `documentation-property' now evaluates the value of
3147 the given property to obtain a string if it doesn't refer to etc/DOC
3148 and isn't a string.
3149
3150 ** If called for a symbol, the function `documentation' now looks for
3151 a `function-documentation' property of that symbol. If it has a non-nil
3152 value, the documentation is taken from that value. If the value is
3153 not a string, it is evaluated to obtain a string.
3154
3155 ** The last argument of `define-key-after' defaults to t for convenience.
3156
3157 ** The new function `replace-regexp-in-string' replaces all matches
3158 for a regexp in a string.
3159
3160 ** `mouse-position' now runs the abnormal hook
3161 `mouse-position-function'.
3162
3163 ** The function string-to-number now returns a float for numbers
3164 that don't fit into a Lisp integer.
3165
3166 ** The variable keyword-symbols-constants-flag has been removed.
3167 Keywords are now always considered constants.
3168
3169 ** The new function `delete-and-extract-region' deletes text and
3170 returns it.
3171
3172 ** The function `clear-this-command-keys' now also clears the vector
3173 returned by function `recent-keys'.
3174
3175 ** Variables `beginning-of-defun-function' and `end-of-defun-function'
3176 can be used to define handlers for the functions that find defuns.
3177 Major modes can define these locally instead of rebinding C-M-a
3178 etc. if the normal conventions for defuns are not appropriate for the
3179 mode.
3180
3181 ** easy-mmode-define-minor-mode now takes an additional BODY argument
3182 and is renamed `define-minor-mode'.
3183
3184 ** If an abbrev has a hook function which is a symbol, and that symbol
3185 has a non-nil `no-self-insert' property, the return value of the hook
3186 function specifies whether an expansion has been done or not. If it
3187 returns nil, abbrev-expand also returns nil, meaning "no expansion has
3188 been performed."
3189
3190 When abbrev expansion is done by typing a self-inserting character,
3191 and the abbrev has a hook with the `no-self-insert' property, and the
3192 hook function returns non-nil meaning expansion has been done,
3193 then the self-inserting character is not inserted.
3194
3195 ** The function `intern-soft' now accepts a symbol as first argument.
3196 In this case, that exact symbol is looked up in the specified obarray,
3197 and the function's value is nil if it is not found.
3198
3199 ** The new macro `with-syntax-table' can be used to evaluate forms
3200 with the syntax table of the current buffer temporarily set to a
3201 specified table.
3202
3203 (with-syntax-table TABLE &rest BODY)
3204
3205 Evaluate BODY with syntax table of current buffer set to a copy of
3206 TABLE. The current syntax table is saved, BODY is evaluated, and the
3207 saved table is restored, even in case of an abnormal exit. Value is
3208 what BODY returns.
3209
3210 ** Regular expressions now support intervals \{n,m\} as well as
3211 Perl's shy-groups \(?:...\) and non-greedy *? +? and ?? operators.
3212 Also back-references like \2 are now considered as an error if the
3213 corresponding subgroup does not exist (or is not closed yet).
3214 Previously it would have been silently turned into `2' (ignoring the `\').
3215
3216 ** The optional argument BUFFER of function file-local-copy has been
3217 removed since it wasn't used by anything.
3218
3219 ** The file name argument of function `file-locked-p' is now required
3220 instead of being optional.
3221
3222 ** The new built-in error `text-read-only' is signaled when trying to
3223 modify read-only text.
3224
3225 ** New functions and variables for locales.
3226
3227 The new variable `locale-coding-system' specifies how to encode and
3228 decode strings passed to low-level message functions like strerror and
3229 time functions like strftime. The new variables
3230 `system-messages-locale' and `system-time-locale' give the system
3231 locales to be used when invoking these two types of functions.
3232
3233 The new function `set-locale-environment' sets the language
3234 environment, preferred coding system, and locale coding system from
3235 the system locale as specified by the LC_ALL, LC_CTYPE, and LANG
3236 environment variables. Normally, it is invoked during startup and need
3237 not be invoked thereafter. It uses the new variables
3238 `locale-language-names', `locale-charset-language-names', and
3239 `locale-preferred-coding-systems' to make its decisions.
3240
3241 ** syntax tables now understand nested comments.
3242 To declare a comment syntax as allowing nesting, just add an `n'
3243 modifier to either of the characters of the comment end and the comment
3244 start sequences.
3245
3246 ** The function `pixmap-spec-p' has been renamed `bitmap-spec-p'
3247 because `bitmap' is more in line with the usual X terminology.
3248
3249 ** New function `propertize'
3250
3251 The new function `propertize' can be used to conveniently construct
3252 strings with text properties.
3253
3254 - Function: propertize STRING &rest PROPERTIES
3255
3256 Value is a copy of STRING with text properties assigned as specified
3257 by PROPERTIES. PROPERTIES is a sequence of pairs PROPERTY VALUE, with
3258 PROPERTY being the name of a text property and VALUE being the
3259 specified value of that property. Example:
3260
3261 (propertize "foo" 'face 'bold 'read-only t)
3262
3263 ** push and pop macros.
3264
3265 Simple versions of the push and pop macros of Common Lisp
3266 are now defined in Emacs Lisp. These macros allow only symbols
3267 as the place that holds the list to be changed.
3268
3269 (push NEWELT LISTNAME) add NEWELT to the front of LISTNAME's value.
3270 (pop LISTNAME) return first elt of LISTNAME, and remove it
3271 (thus altering the value of LISTNAME).
3272
3273 ** New dolist and dotimes macros.
3274
3275 Simple versions of the dolist and dotimes macros of Common Lisp
3276 are now defined in Emacs Lisp.
3277
3278 (dolist (VAR LIST [RESULT]) BODY...)
3279 Execute body once for each element of LIST,
3280 using the variable VAR to hold the current element.
3281 Then return the value of RESULT, or nil if RESULT is omitted.
3282
3283 (dotimes (VAR COUNT [RESULT]) BODY...)
3284 Execute BODY with VAR bound to successive integers running from 0,
3285 inclusive, to COUNT, exclusive.
3286 Then return the value of RESULT, or nil if RESULT is omitted.
3287
3288 ** Regular expressions now support Posix character classes such as
3289 [:alpha:], [:space:] and so on. These must be used within a character
3290 class--for instance, [-[:digit:].+] matches digits or a period
3291 or a sign.
3292
3293 [:digit:] matches 0 through 9
3294 [:cntrl:] matches ASCII control characters
3295 [:xdigit:] matches 0 through 9, a through f and A through F.
3296 [:blank:] matches space and tab only
3297 [:graph:] matches graphic characters--everything except ASCII control chars,
3298 space, and DEL.
3299 [:print:] matches printing characters--everything except ASCII control chars
3300 and DEL.
3301 [:alnum:] matches letters and digits.
3302 (But at present, for multibyte characters,
3303 it matches anything that has word syntax.)
3304 [:alpha:] matches letters.
3305 (But at present, for multibyte characters,
3306 it matches anything that has word syntax.)
3307 [:ascii:] matches ASCII (unibyte) characters.
3308 [:nonascii:] matches non-ASCII (multibyte) characters.
3309 [:lower:] matches anything lower-case.
3310 [:punct:] matches punctuation.
3311 (But at present, for multibyte characters,
3312 it matches anything that has non-word syntax.)
3313 [:space:] matches anything that has whitespace syntax.
3314 [:upper:] matches anything upper-case.
3315 [:word:] matches anything that has word syntax.
3316
3317 ** Emacs now has built-in hash tables.
3318
3319 The following functions are defined for hash tables:
3320
3321 - Function: make-hash-table ARGS
3322
3323 The argument list ARGS consists of keyword/argument pairs. All arguments
3324 are optional. The following arguments are defined:
3325
3326 :test TEST
3327
3328 TEST must be a symbol specifying how to compare keys. Default is `eql'.
3329 Predefined are `eq', `eql' and `equal'. If TEST is not predefined,
3330 it must have been defined with `define-hash-table-test'.
3331
3332 :size SIZE
3333
3334 SIZE must be an integer > 0 giving a hint to the implementation how
3335 many elements will be put in the hash table. Default size is 65.
3336
3337 :rehash-size REHASH-SIZE
3338
3339 REHASH-SIZE specifies by how much to grow a hash table once it becomes
3340 full. If REHASH-SIZE is an integer, add that to the hash table's old
3341 size to get the new size. Otherwise, REHASH-SIZE must be a float >
3342 1.0, and the new size is computed by multiplying REHASH-SIZE with the
3343 old size. Default rehash size is 1.5.
3344
3345 :rehash-threshold THRESHOLD
3346
3347 THRESHOLD must be a float > 0 and <= 1.0 specifying when to resize the
3348 hash table. It is resized when the ratio of (number of entries) /
3349 (size of hash table) is >= THRESHOLD. Default threshold is 0.8.
3350
3351 :weakness WEAK
3352
3353 WEAK must be either nil, one of the symbols `key, `value',
3354 `key-or-value', `key-and-value', or t, meaning the same as
3355 `key-and-value'. Entries are removed from weak tables during garbage
3356 collection if their key and/or value are not referenced elsewhere
3357 outside of the hash table. Default are non-weak hash tables.
3358
3359 - Function: makehash &optional TEST
3360
3361 Similar to make-hash-table, but only TEST can be specified.
3362
3363 - Function: hash-table-p TABLE
3364
3365 Returns non-nil if TABLE is a hash table object.
3366
3367 - Function: copy-hash-table TABLE
3368
3369 Returns a copy of TABLE. Only the table itself is copied, keys and
3370 values are shared.
3371
3372 - Function: hash-table-count TABLE
3373
3374 Returns the number of entries in TABLE.
3375
3376 - Function: hash-table-rehash-size TABLE
3377
3378 Returns the rehash size of TABLE.
3379
3380 - Function: hash-table-rehash-threshold TABLE
3381
3382 Returns the rehash threshold of TABLE.
3383
3384 - Function: hash-table-rehash-size TABLE
3385
3386 Returns the size of TABLE.
3387
3388 - Function: hash-table-test TABLE
3389
3390 Returns the test TABLE uses to compare keys.
3391
3392 - Function: hash-table-weakness TABLE
3393
3394 Returns the weakness specified for TABLE.
3395
3396 - Function: clrhash TABLE
3397
3398 Clear TABLE.
3399
3400 - Function: gethash KEY TABLE &optional DEFAULT
3401
3402 Look up KEY in TABLE and return its associated VALUE or DEFAULT if
3403 not found.
3404
3405 - Function: puthash KEY VALUE TABLE
3406
3407 Associate KEY with VALUE in TABLE. If KEY is already associated with
3408 another value, replace the old value with VALUE.
3409
3410 - Function: remhash KEY TABLE
3411
3412 Remove KEY from TABLE if it is there.
3413
3414 - Function: maphash FUNCTION TABLE
3415
3416 Call FUNCTION for all elements in TABLE. FUNCTION must take two
3417 arguments KEY and VALUE.
3418
3419 - Function: sxhash OBJ
3420
3421 Return a hash code for Lisp object OBJ.
3422
3423 - Function: define-hash-table-test NAME TEST-FN HASH-FN
3424
3425 Define a new hash table test named NAME. If NAME is specified as
3426 a test in `make-hash-table', the table created will use TEST-FN for
3427 comparing keys, and HASH-FN to compute hash codes for keys. Test
3428 and hash function are stored as symbol property `hash-table-test'
3429 of NAME with a value of (TEST-FN HASH-FN).
3430
3431 TEST-FN must take two arguments and return non-nil if they are the same.
3432
3433 HASH-FN must take one argument and return an integer that is the hash
3434 code of the argument. The function should use the whole range of
3435 integer values for hash code computation, including negative integers.
3436
3437 Example: The following creates a hash table whose keys are supposed to
3438 be strings that are compared case-insensitively.
3439
3440 (defun case-fold-string= (a b)
3441 (compare-strings a nil nil b nil nil t))
3442
3443 (defun case-fold-string-hash (a)
3444 (sxhash (upcase a)))
3445
3446 (define-hash-table-test 'case-fold 'case-fold-string=
3447 'case-fold-string-hash))
3448
3449 (make-hash-table :test 'case-fold)
3450
3451 ** The Lisp reader handles circular structure.
3452
3453 It now works to use the #N= and #N# constructs to represent
3454 circular structures. For example, #1=(a . #1#) represents
3455 a cons cell which is its own cdr.
3456
3457 ** The Lisp printer handles circular structure.
3458
3459 If you bind print-circle to a non-nil value, the Lisp printer outputs
3460 #N= and #N# constructs to represent circular and shared structure.
3461
3462 ** If the second argument to `move-to-column' is anything but nil or
3463 t, that means replace a tab with spaces if necessary to reach the
3464 specified column, but do not add spaces at the end of the line if it
3465 is too short to reach that column.
3466
3467 ** perform-replace has a new feature: the REPLACEMENTS argument may
3468 now be a cons cell (FUNCTION . DATA). This means to call FUNCTION
3469 after each match to get the replacement text. FUNCTION is called with
3470 two arguments: DATA, and the number of replacements already made.
3471
3472 If the FROM-STRING contains any upper-case letters,
3473 perform-replace also turns off `case-fold-search' temporarily
3474 and inserts the replacement text without altering case in it.
3475
3476 ** The function buffer-size now accepts an optional argument
3477 to specify which buffer to return the size of.
3478
3479 ** The calendar motion commands now run the normal hook
3480 calendar-move-hook after moving point.
3481
3482 ** The new variable small-temporary-file-directory specifies a
3483 directory to use for creating temporary files that are likely to be
3484 small. (Certain Emacs features use this directory.) If
3485 small-temporary-file-directory is nil, they use
3486 temporary-file-directory instead.
3487
3488 ** The variable `inhibit-modification-hooks', if non-nil, inhibits all
3489 the hooks that track changes in the buffer. This affects
3490 `before-change-functions' and `after-change-functions', as well as
3491 hooks attached to text properties and overlay properties.
3492
3493 ** assq-delete-all is a new function that deletes all the
3494 elements of an alist which have a car `eq' to a particular value.
3495
3496 ** make-temp-file provides a more reliable way to create a temporary file.
3497
3498 make-temp-file is used like make-temp-name, except that it actually
3499 creates the file before it returns. This prevents a timing error,
3500 ensuring that no other job can use the same name for a temporary file.
3501
3502 ** New exclusive-open feature in `write-region'
3503
3504 The optional seventh arg is now called MUSTBENEW. If non-nil, it insists
3505 on a check for an existing file with the same name. If MUSTBENEW
3506 is `excl', that means to get an error if the file already exists;
3507 never overwrite. If MUSTBENEW is neither nil nor `excl', that means
3508 ask for confirmation before overwriting, but do go ahead and
3509 overwrite the file if the user gives confirmation.
3510
3511 If the MUSTBENEW argument in `write-region' is `excl',
3512 that means to use a special feature in the `open' system call
3513 to get an error if the file exists at that time.
3514 The error reported is `file-already-exists'.
3515
3516 ** Function `format' now handles text properties.
3517
3518 Text properties of the format string are applied to the result string.
3519 If the result string is longer than the format string, text properties
3520 ending at the end of the format string are extended to the end of the
3521 result string.
3522
3523 Text properties from string arguments are applied to the result
3524 string where arguments appear in the result string.
3525
3526 Example:
3527
3528 (let ((s1 "hello, %s")
3529 (s2 "world"))
3530 (put-text-property 0 (length s1) 'face 'bold s1)
3531 (put-text-property 0 (length s2) 'face 'italic s2)
3532 (format s1 s2))
3533
3534 results in a bold-face string with an italic `world' at the end.
3535
3536 ** Messages can now be displayed with text properties.
3537
3538 Text properties are handled as described above for function `format'.
3539 The following example displays a bold-face message with an italic
3540 argument in it.
3541
3542 (let ((msg "hello, %s!")
3543 (arg "world"))
3544 (put-text-property 0 (length msg) 'face 'bold msg)
3545 (put-text-property 0 (length arg) 'face 'italic arg)
3546 (message msg arg))
3547
3548 ** Sound support
3549
3550 Emacs supports playing sound files on GNU/Linux and the free BSDs
3551 (Voxware driver and native BSD driver, aka as Luigi's driver).
3552
3553 Currently supported file formats are RIFF-WAVE (*.wav) and Sun Audio
3554 (*.au). You must configure Emacs with the option `--with-sound=yes'
3555 to enable sound support.
3556
3557 Sound files can be played by calling (play-sound SOUND). SOUND is a
3558 list of the form `(sound PROPERTY...)'. The function is only defined
3559 when sound support is present for the system on which Emacs runs. The
3560 functions runs `play-sound-functions' with one argument which is the
3561 sound to play, before playing the sound.
3562
3563 The following sound properties are supported:
3564
3565 - `:file FILE'
3566
3567 FILE is a file name. If FILE isn't an absolute name, it will be
3568 searched relative to `data-directory'.
3569
3570 - `:data DATA'
3571
3572 DATA is a string containing sound data. Either :file or :data
3573 may be present, but not both.
3574
3575 - `:volume VOLUME'
3576
3577 VOLUME must be an integer in the range 0..100 or a float in the range
3578 0..1. This property is optional.
3579
3580 - `:device DEVICE'
3581
3582 DEVICE is a string specifying the system device on which to play the
3583 sound. The default device is system-dependent.
3584
3585 Other properties are ignored.
3586
3587 An alternative interface is called as
3588 (play-sound-file FILE &optional VOLUME DEVICE).
3589
3590 ** `multimedia' is a new Finder keyword and Custom group.
3591
3592 ** keywordp is a new predicate to test efficiently for an object being
3593 a keyword symbol.
3594
3595 ** Changes to garbage collection
3596
3597 *** The function garbage-collect now additionally returns the number
3598 of live and free strings.
3599
3600 *** There is a new variable `strings-consed' holding the number of
3601 strings that have been consed so far.
3602
3603 \f
3604 * Lisp-level Display features added after release 2.6 of the Emacs
3605 Lisp Manual
3606
3607 ** The user-option `resize-mini-windows' controls how Emacs resizes
3608 mini-windows.
3609
3610 ** The function `pos-visible-in-window-p' now has a third optional
3611 argument, PARTIALLY. If a character is only partially visible, nil is
3612 returned, unless PARTIALLY is non-nil.
3613
3614 ** On window systems, `glyph-table' is no longer used.
3615
3616 ** Help strings in menu items are now used to provide `help-echo' text.
3617
3618 ** The function `image-size' can be used to determine the size of an
3619 image.
3620
3621 - Function: image-size SPEC &optional PIXELS FRAME
3622
3623 Return the size of an image as a pair (WIDTH . HEIGHT).
3624
3625 SPEC is an image specification. PIXELS non-nil means return sizes
3626 measured in pixels, otherwise return sizes measured in canonical
3627 character units (fractions of the width/height of the frame's default
3628 font). FRAME is the frame on which the image will be displayed.
3629 FRAME nil or omitted means use the selected frame.
3630
3631 ** The function `image-mask-p' can be used to determine if an image
3632 has a mask bitmap.
3633
3634 - Function: image-mask-p SPEC &optional FRAME
3635
3636 Return t if image SPEC has a mask bitmap.
3637 FRAME is the frame on which the image will be displayed. FRAME nil
3638 or omitted means use the selected frame.
3639
3640 ** The function `find-image' can be used to find a usable image
3641 satisfying one of a list of specifications.
3642
3643 ** The STRING argument of `put-image' and `insert-image' is now
3644 optional.
3645
3646 ** Image specifications may contain the property `:ascent center' (see
3647 below).
3648
3649 \f
3650 * New Lisp-level Display features in Emacs 21.1
3651
3652 Note that +++ before an item means the Lisp manual has been updated.
3653 --- means that I have decided it does not need to be in the Lisp manual.
3654 When you add a new item, please add it without either +++ or ---
3655 so I will know I still need to look at it -- rms.
3656
3657 ** The function tty-suppress-bold-inverse-default-colors can be used
3658 to make Emacs avoid displaying text with bold black foreground on TTYs.
3659
3660 Some terminals, notably PC consoles, emulate bold text by displaying
3661 text in brighter colors. On such a console, a bold black foreground
3662 is displayed in a gray color. If this turns out to be hard to read on
3663 your monitor---the problem occurred with the mode line on
3664 laptops---you can instruct Emacs to ignore the text's boldness, and to
3665 just display it black instead.
3666
3667 This situation can't be detected automatically. You will have to put
3668 a line like
3669
3670 (tty-suppress-bold-inverse-default-colors t)
3671
3672 in your `.emacs'.
3673
3674 ** New face implementation.
3675
3676 Emacs faces have been reimplemented from scratch. They don't use XLFD
3677 font names anymore and face merging now works as expected.
3678
3679 *** New faces.
3680
3681 Each face can specify the following display attributes:
3682
3683 1. Font family or fontset alias name.
3684
3685 2. Relative proportionate width, aka character set width or set
3686 width (swidth), e.g. `semi-compressed'.
3687
3688 3. Font height in 1/10pt
3689
3690 4. Font weight, e.g. `bold'.
3691
3692 5. Font slant, e.g. `italic'.
3693
3694 6. Foreground color.
3695
3696 7. Background color.
3697
3698 8. Whether or not characters should be underlined, and in what color.
3699
3700 9. Whether or not characters should be displayed in inverse video.
3701
3702 10. A background stipple, a bitmap.
3703
3704 11. Whether or not characters should be overlined, and in what color.
3705
3706 12. Whether or not characters should be strike-through, and in what
3707 color.
3708
3709 13. Whether or not a box should be drawn around characters, its
3710 color, the width of the box lines, and 3D appearance.
3711
3712 Faces are frame-local by nature because Emacs allows to define the
3713 same named face (face names are symbols) differently for different
3714 frames. Each frame has an alist of face definitions for all named
3715 faces. The value of a named face in such an alist is a Lisp vector
3716 with the symbol `face' in slot 0, and a slot for each of the face
3717 attributes mentioned above.
3718
3719 There is also a global face alist `face-new-frame-defaults'. Face
3720 definitions from this list are used to initialize faces of newly
3721 created frames.
3722
3723 A face doesn't have to specify all attributes. Those not specified
3724 have a nil value. Faces specifying all attributes are called
3725 `fully-specified'.
3726
3727 *** Face merging.
3728
3729 The display style of a given character in the text is determined by
3730 combining several faces. This process is called `face merging'. Any
3731 aspect of the display style that isn't specified by overlays or text
3732 properties is taken from the `default' face. Since it is made sure
3733 that the default face is always fully-specified, face merging always
3734 results in a fully-specified face.
3735
3736 *** Face realization.
3737
3738 After all face attributes for a character have been determined by
3739 merging faces of that character, that face is `realized'. The
3740 realization process maps face attributes to what is physically
3741 available on the system where Emacs runs. The result is a `realized
3742 face' in form of an internal structure which is stored in the face
3743 cache of the frame on which it was realized.
3744
3745 Face realization is done in the context of the charset of the
3746 character to display because different fonts and encodings are used
3747 for different charsets. In other words, for characters of different
3748 charsets, different realized faces are needed to display them.
3749
3750 Except for composite characters, faces are always realized for a
3751 specific character set and contain a specific font, even if the face
3752 being realized specifies a fontset. The reason is that the result of
3753 the new font selection stage is better than what can be done with
3754 statically defined font name patterns in fontsets.
3755
3756 In unibyte text, Emacs' charsets aren't applicable; function
3757 `char-charset' reports ASCII for all characters, including those >
3758 0x7f. The X registry and encoding of fonts to use is determined from
3759 the variable `face-default-registry' in this case. The variable is
3760 initialized at Emacs startup time from the font the user specified for
3761 Emacs.
3762
3763 Currently all unibyte text, i.e. all buffers with
3764 `enable-multibyte-characters' nil are displayed with fonts of the same
3765 registry and encoding `face-default-registry'. This is consistent
3766 with the fact that languages can also be set globally, only.
3767
3768 **** Clearing face caches.
3769
3770 The Lisp function `clear-face-cache' can be called to clear face caches
3771 on all frames. If called with a non-nil argument, it will also unload
3772 unused fonts.
3773
3774 *** Font selection.
3775
3776 Font selection tries to find the best available matching font for a
3777 given (charset, face) combination. This is done slightly differently
3778 for faces specifying a fontset, or a font family name.
3779
3780 If the face specifies a fontset name, that fontset determines a
3781 pattern for fonts of the given charset. If the face specifies a font
3782 family, a font pattern is constructed. Charset symbols have a
3783 property `x-charset-registry' for that purpose that maps a charset to
3784 an XLFD registry and encoding in the font pattern constructed.
3785
3786 Available fonts on the system on which Emacs runs are then matched
3787 against the font pattern. The result of font selection is the best
3788 match for the given face attributes in this font list.
3789
3790 Font selection can be influenced by the user.
3791
3792 The user can specify the relative importance he gives the face
3793 attributes width, height, weight, and slant by setting
3794 face-font-selection-order (faces.el) to a list of face attribute
3795 names. The default is (:width :height :weight :slant), and means
3796 that font selection first tries to find a good match for the font
3797 width specified by a face, then---within fonts with that width---tries
3798 to find a best match for the specified font height, etc.
3799
3800 Setting `face-font-family-alternatives' allows the user to specify
3801 alternative font families to try if a family specified by a face
3802 doesn't exist.
3803
3804 Setting `face-font-registry-alternatives' allows the user to specify
3805 all alternative font registry names to try for a face specifying a
3806 registry.
3807
3808 Please note that the interpretations of the above two variables are
3809 slightly different.
3810
3811 Setting face-ignored-fonts allows the user to ignore specific fonts.
3812
3813
3814 **** Scalable fonts
3815
3816 Emacs can make use of scalable fonts but doesn't do so by default,
3817 since the use of too many or too big scalable fonts may crash XFree86
3818 servers.
3819
3820 To enable scalable font use, set the variable
3821 `scalable-fonts-allowed'. A value of nil, the default, means never use
3822 scalable fonts. A value of t means any scalable font may be used.
3823 Otherwise, the value must be a list of regular expressions. A
3824 scalable font may then be used if it matches a regular expression from
3825 that list. Example:
3826
3827 (setq scalable-fonts-allowed '("muleindian-2$"))
3828
3829 allows the use of scalable fonts with registry `muleindian-2'.
3830
3831 *** Functions and variables related to font selection.
3832
3833 - Function: x-family-fonts &optional FAMILY FRAME
3834
3835 Return a list of available fonts of family FAMILY on FRAME. If FAMILY
3836 is omitted or nil, list all families. Otherwise, FAMILY must be a
3837 string, possibly containing wildcards `?' and `*'.
3838
3839 If FRAME is omitted or nil, use the selected frame. Each element of
3840 the result is a vector [FAMILY WIDTH POINT-SIZE WEIGHT SLANT FIXED-P
3841 FULL REGISTRY-AND-ENCODING]. FAMILY is the font family name.
3842 POINT-SIZE is the size of the font in 1/10 pt. WIDTH, WEIGHT, and
3843 SLANT are symbols describing the width, weight and slant of the font.
3844 These symbols are the same as for face attributes. FIXED-P is non-nil
3845 if the font is fixed-pitch. FULL is the full name of the font, and
3846 REGISTRY-AND-ENCODING is a string giving the registry and encoding of
3847 the font. The result list is sorted according to the current setting
3848 of the face font sort order.
3849
3850 - Function: x-font-family-list
3851
3852 Return a list of available font families on FRAME. If FRAME is
3853 omitted or nil, use the selected frame. Value is a list of conses
3854 (FAMILY . FIXED-P) where FAMILY is a font family, and FIXED-P is
3855 non-nil if fonts of that family are fixed-pitch.
3856
3857 - Variable: font-list-limit
3858
3859 Limit for font matching. If an integer > 0, font matching functions
3860 won't load more than that number of fonts when searching for a
3861 matching font. The default is currently 100.
3862
3863 *** Setting face attributes.
3864
3865 For the most part, the new face implementation is interface-compatible
3866 with the old one. Old face attribute related functions are now
3867 implemented in terms of the new functions `set-face-attribute' and
3868 `face-attribute'.
3869
3870 Face attributes are identified by their names which are keyword
3871 symbols. All attributes can be set to `unspecified'.
3872
3873 The following attributes are recognized:
3874
3875 `:family'
3876
3877 VALUE must be a string specifying the font family, e.g. ``courier'',
3878 or a fontset alias name. If a font family is specified, wild-cards `*'
3879 and `?' are allowed.
3880
3881 `:width'
3882
3883 VALUE specifies the relative proportionate width of the font to use.
3884 It must be one of the symbols `ultra-condensed', `extra-condensed',
3885 `condensed', `semi-condensed', `normal', `semi-expanded', `expanded',
3886 `extra-expanded', or `ultra-expanded'.
3887
3888 `:height'
3889
3890 VALUE must be either an integer specifying the height of the font to use
3891 in 1/10 pt, a floating point number specifying the amount by which to
3892 scale any underlying face, or a function, which is called with the old
3893 height (from the underlying face), and should return the new height.
3894
3895 `:weight'
3896
3897 VALUE specifies the weight of the font to use. It must be one of the
3898 symbols `ultra-bold', `extra-bold', `bold', `semi-bold', `normal',
3899 `semi-light', `light', `extra-light', `ultra-light'.
3900
3901 `:slant'
3902
3903 VALUE specifies the slant of the font to use. It must be one of the
3904 symbols `italic', `oblique', `normal', `reverse-italic', or
3905 `reverse-oblique'.
3906
3907 `:foreground', `:background'
3908
3909 VALUE must be a color name, a string.
3910
3911 `:underline'
3912
3913 VALUE specifies whether characters in FACE should be underlined. If
3914 VALUE is t, underline with foreground color of the face. If VALUE is
3915 a string, underline with that color. If VALUE is nil, explicitly
3916 don't underline.
3917
3918 `:overline'
3919
3920 VALUE specifies whether characters in FACE should be overlined. If
3921 VALUE is t, overline with foreground color of the face. If VALUE is a
3922 string, overline with that color. If VALUE is nil, explicitly don't
3923 overline.
3924
3925 `:strike-through'
3926
3927 VALUE specifies whether characters in FACE should be drawn with a line
3928 striking through them. If VALUE is t, use the foreground color of the
3929 face. If VALUE is a string, strike-through with that color. If VALUE
3930 is nil, explicitly don't strike through.
3931
3932 `:box'
3933
3934 VALUE specifies whether characters in FACE should have a box drawn
3935 around them. If VALUE is nil, explicitly don't draw boxes. If
3936 VALUE is t, draw a box with lines of width 1 in the foreground color
3937 of the face. If VALUE is a string, the string must be a color name,
3938 and the box is drawn in that color with a line width of 1. Otherwise,
3939 VALUE must be a property list of the form `(:line-width WIDTH
3940 :color COLOR :style STYLE)'. If a keyword/value pair is missing from
3941 the property list, a default value will be used for the value, as
3942 specified below. WIDTH specifies the width of the lines to draw; it
3943 defaults to 1. COLOR is the name of the color to draw in, default is
3944 the foreground color of the face for simple boxes, and the background
3945 color of the face for 3D boxes. STYLE specifies whether a 3D box
3946 should be draw. If STYLE is `released-button', draw a box looking
3947 like a released 3D button. If STYLE is `pressed-button' draw a box
3948 that appears like a pressed button. If STYLE is nil, the default if
3949 the property list doesn't contain a style specification, draw a 2D
3950 box.
3951
3952 `:inverse-video'
3953
3954 VALUE specifies whether characters in FACE should be displayed in
3955 inverse video. VALUE must be one of t or nil.
3956
3957 `:stipple'
3958
3959 If VALUE is a string, it must be the name of a file of pixmap data.
3960 The directories listed in the `x-bitmap-file-path' variable are
3961 searched. Alternatively, VALUE may be a list of the form (WIDTH
3962 HEIGHT DATA) where WIDTH and HEIGHT are the size in pixels, and DATA
3963 is a string containing the raw bits of the bitmap. VALUE nil means
3964 explicitly don't use a stipple pattern.
3965
3966 For convenience, attributes `:family', `:width', `:height', `:weight',
3967 and `:slant' may also be set in one step from an X font name:
3968
3969 `:font'
3970
3971 Set font-related face attributes from VALUE. VALUE must be a valid
3972 XLFD font name. If it is a font name pattern, the first matching font
3973 is used--this is for compatibility with the behavior of previous
3974 versions of Emacs.
3975
3976 For compatibility with Emacs 20, keywords `:bold' and `:italic' can
3977 be used to specify that a bold or italic font should be used. VALUE
3978 must be t or nil in that case. A value of `unspecified' is not allowed."
3979
3980 Please see also the documentation of `set-face-attribute' and
3981 `defface'.
3982
3983 `:inherit'
3984
3985 VALUE is the name of a face from which to inherit attributes, or a list
3986 of face names. Attributes from inherited faces are merged into the face
3987 like an underlying face would be, with higher priority than underlying faces.
3988
3989 *** Face attributes and X resources
3990
3991 The following X resource names can be used to set face attributes
3992 from X resources:
3993
3994 Face attribute X resource class
3995 -----------------------------------------------------------------------
3996 :family attributeFamily . Face.AttributeFamily
3997 :width attributeWidth Face.AttributeWidth
3998 :height attributeHeight Face.AttributeHeight
3999 :weight attributeWeight Face.AttributeWeight
4000 :slant attributeSlant Face.AttributeSlant
4001 foreground attributeForeground Face.AttributeForeground
4002 :background attributeBackground . Face.AttributeBackground
4003 :overline attributeOverline Face.AttributeOverline
4004 :strike-through attributeStrikeThrough Face.AttributeStrikeThrough
4005 :box attributeBox Face.AttributeBox
4006 :underline attributeUnderline Face.AttributeUnderline
4007 :inverse-video attributeInverse Face.AttributeInverse
4008 :stipple attributeStipple Face.AttributeStipple
4009 or attributeBackgroundPixmap
4010 Face.AttributeBackgroundPixmap
4011 :font attributeFont Face.AttributeFont
4012 :bold attributeBold Face.AttributeBold
4013 :italic attributeItalic . Face.AttributeItalic
4014 :font attributeFont Face.AttributeFont
4015
4016 *** Text property `face'.
4017
4018 The value of the `face' text property can now be a single face
4019 specification or a list of such specifications. Each face
4020 specification can be
4021
4022 1. A symbol or string naming a Lisp face.
4023
4024 2. A property list of the form (KEYWORD VALUE ...) where each
4025 KEYWORD is a face attribute name, and VALUE is an appropriate value
4026 for that attribute. Please see the doc string of `set-face-attribute'
4027 for face attribute names.
4028
4029 3. Conses of the form (FOREGROUND-COLOR . COLOR) or
4030 (BACKGROUND-COLOR . COLOR) where COLOR is a color name. This is
4031 for compatibility with previous Emacs versions.
4032
4033 ** Support functions for colors on text-only terminals.
4034
4035 The function `tty-color-define' can be used to define colors for use
4036 on TTY and MSDOS frames. It maps a color name to a color number on
4037 the terminal. Emacs defines a couple of common color mappings by
4038 default. You can get defined colors with a call to
4039 `defined-colors'. The function `tty-color-clear' can be
4040 used to clear the mapping table.
4041
4042 ** Unified support for colors independent of frame type.
4043
4044 The new functions `defined-colors', `color-defined-p', `color-values',
4045 and `display-color-p' work for any type of frame. On frames whose
4046 type is neither x nor w32, these functions transparently map X-style
4047 color specifications to the closest colors supported by the frame
4048 display. Lisp programs should use these new functions instead of the
4049 old `x-defined-colors', `x-color-defined-p', `x-color-values', and
4050 `x-display-color-p'. (The old function names are still available for
4051 compatibility; they are now aliases of the new names.) Lisp programs
4052 should no more look at the value of the variable window-system to
4053 modify their color-related behavior.
4054
4055 The primitives `color-gray-p' and `color-supported-p' also work for
4056 any frame type.
4057
4058 ** Platform-independent functions to describe display capabilities.
4059
4060 The new functions `display-mouse-p', `display-popup-menus-p',
4061 `display-graphic-p', `display-selections-p', `display-screens',
4062 `display-pixel-width', `display-pixel-height', `display-mm-width',
4063 `display-mm-height', `display-backing-store', `display-save-under',
4064 `display-planes', `display-color-cells', `display-visual-class', and
4065 `display-grayscale-p' describe the basic capabilities of a particular
4066 display. Lisp programs should call these functions instead of testing
4067 the value of the variables `window-system' or `system-type', or calling
4068 platform-specific functions such as `x-display-pixel-width'.
4069
4070 The new function `display-images-p' returns non-nil if a particular
4071 display can display image files.
4072
4073 ** The minibuffer prompt is now actually inserted in the minibuffer.
4074
4075 This makes it possible to scroll through the prompt, if you want to.
4076 To disallow this completely (like previous versions of emacs), customize
4077 the variable `minibuffer-prompt-properties', and turn on the
4078 `Inviolable' option.
4079
4080 The function minibuffer-prompt-end returns the current position of the
4081 end of the minibuffer prompt, if the minibuffer is current.
4082 Otherwise, it returns zero.
4083
4084 ** New `field' abstraction in buffers.
4085
4086 There is now code to support an abstraction called `fields' in emacs
4087 buffers. A field is a contiguous region of text with the same `field'
4088 property (which can be a text property or an overlay).
4089
4090 Many emacs functions, such as forward-word, forward-sentence,
4091 forward-paragraph, beginning-of-line, etc., stop moving when they come
4092 to the boundary between fields; beginning-of-line and end-of-line will
4093 not let the point move past the field boundary, but other movement
4094 commands continue into the next field if repeated. Stopping at field
4095 boundaries can be suppressed programmatically by binding
4096 `inhibit-field-text-motion' to a non-nil value around calls to these
4097 functions.
4098
4099 Now that the minibuffer prompt is inserted into the minibuffer, it is in
4100 a separate field from the user-input part of the buffer, so that common
4101 editing commands treat the user's text separately from the prompt.
4102
4103 The following functions are defined for operating on fields:
4104
4105 - Function: constrain-to-field NEW-POS OLD-POS &optional ESCAPE-FROM-EDGE ONLY-IN-LINE INHIBIT-CAPTURE-PROPERTY
4106
4107 Return the position closest to NEW-POS that is in the same field as OLD-POS.
4108
4109 A field is a region of text with the same `field' property.
4110 If NEW-POS is nil, then the current point is used instead, and set to the
4111 constrained position if that is different.
4112
4113 If OLD-POS is at the boundary of two fields, then the allowable
4114 positions for NEW-POS depends on the value of the optional argument
4115 ESCAPE-FROM-EDGE: If ESCAPE-FROM-EDGE is nil, then NEW-POS is
4116 constrained to the field that has the same `field' char-property
4117 as any new characters inserted at OLD-POS, whereas if ESCAPE-FROM-EDGE
4118 is non-nil, NEW-POS is constrained to the union of the two adjacent
4119 fields. Additionally, if two fields are separated by another field with
4120 the special value `boundary', then any point within this special field is
4121 also considered to be `on the boundary'.
4122
4123 If the optional argument ONLY-IN-LINE is non-nil and constraining
4124 NEW-POS would move it to a different line, NEW-POS is returned
4125 unconstrained. This useful for commands that move by line, like
4126 C-n or C-a, which should generally respect field boundaries
4127 only in the case where they can still move to the right line.
4128
4129 If the optional argument INHIBIT-CAPTURE-PROPERTY is non-nil, and OLD-POS has
4130 a non-nil property of that name, then any field boundaries are ignored.
4131
4132 Field boundaries are not noticed if `inhibit-field-text-motion' is non-nil.
4133
4134 - Function: delete-field &optional POS
4135
4136 Delete the field surrounding POS.
4137 A field is a region of text with the same `field' property.
4138 If POS is nil, the value of point is used for POS.
4139
4140 - Function: field-beginning &optional POS ESCAPE-FROM-EDGE
4141
4142 Return the beginning of the field surrounding POS.
4143 A field is a region of text with the same `field' property.
4144 If POS is nil, the value of point is used for POS.
4145 If ESCAPE-FROM-EDGE is non-nil and POS is at the beginning of its
4146 field, then the beginning of the *previous* field is returned.
4147
4148 - Function: field-end &optional POS ESCAPE-FROM-EDGE
4149
4150 Return the end of the field surrounding POS.
4151 A field is a region of text with the same `field' property.
4152 If POS is nil, the value of point is used for POS.
4153 If ESCAPE-FROM-EDGE is non-nil and POS is at the end of its field,
4154 then the end of the *following* field is returned.
4155
4156 - Function: field-string &optional POS
4157
4158 Return the contents of the field surrounding POS as a string.
4159 A field is a region of text with the same `field' property.
4160 If POS is nil, the value of point is used for POS.
4161
4162 - Function: field-string-no-properties &optional POS
4163
4164 Return the contents of the field around POS, without text-properties.
4165 A field is a region of text with the same `field' property.
4166 If POS is nil, the value of point is used for POS.
4167
4168 ** Image support.
4169
4170 Emacs can now display images. Images are inserted into text by giving
4171 strings or buffer text a `display' text property containing one of
4172 (AREA IMAGE) or IMAGE. The display of the `display' property value
4173 replaces the display of the characters having that property.
4174
4175 If the property value has the form (AREA IMAGE), AREA must be one of
4176 `(margin left-margin)', `(margin right-margin)' or `(margin nil)'. If
4177 AREA is `(margin nil)', IMAGE will be displayed in the text area of a
4178 window, otherwise it will be displayed in the left or right marginal
4179 area.
4180
4181 IMAGE is an image specification.
4182
4183 *** Image specifications
4184
4185 Image specifications are lists of the form `(image PROPS)' where PROPS
4186 is a property list whose keys are keyword symbols. Each
4187 specifications must contain a property `:type TYPE' with TYPE being a
4188 symbol specifying the image type, e.g. `xbm'. Properties not
4189 described below are ignored.
4190
4191 The following is a list of properties all image types share.
4192
4193 `:ascent ASCENT'
4194
4195 ASCENT must be a number in the range 0..100, or the symbol `center'.
4196 If it is a number, it specifies the percentage of the image's height
4197 to use for its ascent.
4198
4199 If not specified, ASCENT defaults to the value 50 which means that the
4200 image will be centered with the base line of the row it appears in.
4201
4202 If ASCENT is `center' the image is vertically centered around a
4203 centerline which is the vertical center of text drawn at the position
4204 of the image, in the manner specified by the text properties and
4205 overlays that apply to the image.
4206
4207 `:margin MARGIN'
4208
4209 MARGIN must be either a number >= 0 specifying how many pixels to put
4210 as margin around the image, or a pair (X . Y) with X specifying the
4211 horizontal margin and Y specifying the vertical margin. Default is 0.
4212
4213 `:relief RELIEF'
4214
4215 RELIEF is analogous to the `:relief' attribute of faces. Puts a relief
4216 around an image.
4217
4218 `:conversion ALGO'
4219
4220 Apply an image algorithm to the image before displaying it.
4221
4222 ALGO `laplace' or `emboss' means apply a Laplace or ``emboss''
4223 edge-detection algorithm to the image.
4224
4225 ALGO `(edge-detection :matrix MATRIX :color-adjust ADJUST)' means
4226 apply a general edge-detection algorithm. MATRIX must be either a
4227 nine-element list or a nine-element vector of numbers. A pixel at
4228 position x/y in the transformed image is computed from original pixels
4229 around that position. MATRIX specifies, for each pixel in the
4230 neighborhood of x/y, a factor with which that pixel will influence the
4231 transformed pixel; element 0 specifies the factor for the pixel at
4232 x-1/y-1, element 1 the factor for the pixel at x/y-1 etc. as shown
4233 below.
4234
4235 (x-1/y-1 x/y-1 x+1/y-1
4236 x-1/y x/y x+1/y
4237 x-1/y+1 x/y+1 x+1/y+1)
4238
4239 The resulting pixel is computed from the color intensity of the color
4240 resulting from summing up the RGB values of surrounding pixels,
4241 multiplied by the specified factors, and dividing that sum by the sum
4242 of the factors' absolute values.
4243
4244 Laplace edge-detection currently uses a matrix of
4245
4246 (1 0 0
4247 0 0 0
4248 9 9 -1)
4249
4250 Emboss edge-detection uses a matrix of
4251
4252 ( 2 -1 0
4253 -1 0 1
4254 0 1 -2)
4255
4256 ALGO `disabled' means transform the image so that it looks
4257 ``disabled''.
4258
4259 `:mask MASK'
4260
4261 If MASK is `heuristic' or `(heuristic BG)', build a clipping mask for
4262 the image, so that the background of a frame is visible behind the
4263 image. If BG is not specified, or if BG is t, determine the
4264 background color of the image by looking at the 4 corners of the
4265 image, assuming the most frequently occurring color from the corners is
4266 the background color of the image. Otherwise, BG must be a list `(RED
4267 GREEN BLUE)' specifying the color to assume for the background of the
4268 image.
4269
4270 If MASK is nil, remove a mask from the image, if it has one. Images
4271 in some formats include a mask which can be removed by specifying
4272 `:mask nil'.
4273
4274 `:file FILE'
4275
4276 Load image from FILE. If FILE is not absolute after expanding it,
4277 search for the image in `data-directory'. Some image types support
4278 building images from data. When this is done, no `:file' property
4279 may be present in the image specification.
4280
4281 `:data DATA'
4282
4283 Get image data from DATA. (As of this writing, this is not yet
4284 supported for image type `postscript'). Either :file or :data may be
4285 present in an image specification, but not both. All image types
4286 support strings as DATA, some types allow additional types of DATA.
4287
4288 *** Supported image types
4289
4290 **** XBM, image type `xbm'.
4291
4292 XBM images don't require an external library. Additional image
4293 properties supported are
4294
4295 `:foreground FG'
4296
4297 FG must be a string specifying the image foreground color, or nil
4298 meaning to use the default. Default is the frame's foreground.
4299
4300 `:background BG'
4301
4302 BG must be a string specifying the image foreground color, or nil
4303 meaning to use the default. Default is the frame's background color.
4304
4305 XBM images can be constructed from data instead of file. In this
4306 case, the image specification must contain the following properties
4307 instead of a `:file' property.
4308
4309 `:width WIDTH'
4310
4311 WIDTH specifies the width of the image in pixels.
4312
4313 `:height HEIGHT'
4314
4315 HEIGHT specifies the height of the image in pixels.
4316
4317 `:data DATA'
4318
4319 DATA must be either
4320
4321 1. a string large enough to hold the bitmap data, i.e. it must
4322 have a size >= (WIDTH + 7) / 8 * HEIGHT
4323
4324 2. a bool-vector of size >= WIDTH * HEIGHT
4325
4326 3. a vector of strings or bool-vectors, one for each line of the
4327 bitmap.
4328
4329 4. a string that's an in-memory XBM file. Neither width nor
4330 height may be specified in this case because these are defined
4331 in the file.
4332
4333 **** XPM, image type `xpm'
4334
4335 XPM images require the external library `libXpm', package
4336 `xpm-3.4k.tar.gz', version 3.4k or later. Make sure the library is
4337 found when Emacs is configured by supplying appropriate paths via
4338 `--x-includes' and `--x-libraries'.
4339
4340 Additional image properties supported are:
4341
4342 `:color-symbols SYMBOLS'
4343
4344 SYMBOLS must be a list of pairs (NAME . COLOR), with NAME being the
4345 name of color as it appears in an XPM file, and COLOR being an X color
4346 name.
4347
4348 XPM images can be built from memory instead of files. In that case,
4349 add a `:data' property instead of a `:file' property.
4350
4351 The XPM library uses libz in its implementation so that it is able
4352 to display compressed images.
4353
4354 **** PBM, image type `pbm'
4355
4356 PBM images don't require an external library. Color, gray-scale and
4357 mono images are supported. Additional image properties supported for
4358 mono images are
4359
4360 `:foreground FG'
4361
4362 FG must be a string specifying the image foreground color, or nil
4363 meaning to use the default. Default is the frame's foreground.
4364
4365 `:background FG'
4366
4367 BG must be a string specifying the image foreground color, or nil
4368 meaning to use the default. Default is the frame's background color.
4369
4370 **** JPEG, image type `jpeg'
4371
4372 Support for JPEG images requires the external library `libjpeg',
4373 package `jpegsrc.v6a.tar.gz', or later. Additional image properties
4374 are:
4375
4376 **** TIFF, image type `tiff'
4377
4378 Support for TIFF images requires the external library `libtiff',
4379 package `tiff-v3.4-tar.gz', or later. There are no additional image
4380 properties defined.
4381
4382 **** GIF, image type `gif'
4383
4384 Support for GIF images requires the external library `libungif', package
4385 `libungif-4.1.0', or later.
4386
4387 Additional image properties supported are:
4388
4389 `:index INDEX'
4390
4391 INDEX must be an integer >= 0. Load image number INDEX from a
4392 multi-image GIF file. An error is signaled if INDEX is too large.
4393
4394 This could be used to implement limited support for animated GIFs.
4395 For example, the following function displays a multi-image GIF file
4396 at point-min in the current buffer, switching between sub-images
4397 every 0.1 seconds.
4398
4399 (defun show-anim (file max)
4400 "Display multi-image GIF file FILE which contains MAX subimages."
4401 (display-anim (current-buffer) file 0 max t))
4402
4403 (defun display-anim (buffer file idx max first-time)
4404 (when (= idx max)
4405 (setq idx 0))
4406 (let ((img (create-image file nil nil :index idx)))
4407 (save-excursion
4408 (set-buffer buffer)
4409 (goto-char (point-min))
4410 (unless first-time (delete-char 1))
4411 (insert-image img "x"))
4412 (run-with-timer 0.1 nil 'display-anim buffer file (1+ idx) max nil)))
4413
4414 **** PNG, image type `png'
4415
4416 Support for PNG images requires the external library `libpng',
4417 package `libpng-1.0.2.tar.gz', or later. There are no additional image
4418 properties defined.
4419
4420 **** Ghostscript, image type `postscript'.
4421
4422 Additional image properties supported are:
4423
4424 `:pt-width WIDTH'
4425
4426 WIDTH is width of the image in pt (1/72 inch). WIDTH must be an
4427 integer. This is a required property.
4428
4429 `:pt-height HEIGHT'
4430
4431 HEIGHT specifies the height of the image in pt (1/72 inch). HEIGHT
4432 must be a integer. This is an required property.
4433
4434 `:bounding-box BOX'
4435
4436 BOX must be a list or vector of 4 integers giving the bounding box of
4437 the PS image, analogous to the `BoundingBox' comment found in PS
4438 files. This is an required property.
4439
4440 Part of the Ghostscript interface is implemented in Lisp. See
4441 lisp/gs.el.
4442
4443 *** Lisp interface.
4444
4445 The variable `image-types' contains a list of those image types
4446 which are supported in the current configuration.
4447
4448 Images are stored in an image cache and removed from the cache when
4449 they haven't been displayed for `image-cache-eviction-delay seconds.
4450 The function `clear-image-cache' can be used to clear the image cache
4451 manually. Images in the cache are compared with `equal', i.e. all
4452 images with `equal' specifications share the same image.
4453
4454 *** Simplified image API, image.el
4455
4456 The new Lisp package image.el contains functions that simplify image
4457 creation and putting images into text. The function `create-image'
4458 can be used to create images. The macro `defimage' can be used to
4459 define an image based on available image types. The functions
4460 `put-image' and `insert-image' can be used to insert an image into a
4461 buffer.
4462
4463 ** Display margins.
4464
4465 Windows can now have margins which are used for special text
4466 and images.
4467
4468 To give a window margins, either set the buffer-local variables
4469 `left-margin-width' and `right-margin-width', or call
4470 `set-window-margins'. The function `window-margins' can be used to
4471 obtain the current settings. To make `left-margin-width' and
4472 `right-margin-width' take effect, you must set them before displaying
4473 the buffer in a window, or use `set-window-buffer' to force an update
4474 of the display margins.
4475
4476 You can put text in margins by giving it a `display' text property
4477 containing a pair of the form `(LOCATION . VALUE)', where LOCATION is
4478 one of `left-margin' or `right-margin' or nil. VALUE can be either a
4479 string, an image specification or a stretch specification (see later
4480 in this file).
4481
4482 ** Help display
4483
4484 Emacs displays short help messages in the echo area, when the mouse
4485 moves over a tool-bar item or a piece of text that has a text property
4486 `help-echo'. This feature also applies to strings in the mode line
4487 that have a `help-echo' property.
4488
4489 If the value of the `help-echo' property is a function, that function
4490 is called with three arguments WINDOW, OBJECT and POSITION. WINDOW is
4491 the window in which the help was found.
4492
4493 If OBJECT is a buffer, POS is the position in the buffer where the
4494 `help-echo' text property was found.
4495
4496 If OBJECT is an overlay, that overlay has a `help-echo' property, and
4497 POS is the position in the overlay's buffer under the mouse.
4498
4499 If OBJECT is a string (an overlay string or a string displayed with
4500 the `display' property), POS is the position in that string under the
4501 mouse.
4502
4503 If the value of the `help-echo' property is neither a function nor a
4504 string, it is evaluated to obtain a help string.
4505
4506 For tool-bar and menu-bar items, their key definition is used to
4507 determine the help to display. If their definition contains a
4508 property `:help FORM', FORM is evaluated to determine the help string.
4509 For tool-bar items without a help form, the caption of the item is
4510 used as help string.
4511
4512 The hook `show-help-function' can be set to a function that displays
4513 the help string differently. For example, enabling a tooltip window
4514 causes the help display to appear there instead of in the echo area.
4515
4516 ** Vertical fractional scrolling.
4517
4518 The display of text in windows can be scrolled smoothly in pixels.
4519 This is useful, for example, for making parts of large images visible.
4520
4521 The function `window-vscroll' returns the current value of vertical
4522 scrolling, a non-negative fraction of the canonical character height.
4523 The function `set-window-vscroll' can be used to set the vertical
4524 scrolling value. Here is an example of how these function might be
4525 used.
4526
4527 (global-set-key [A-down]
4528 #'(lambda ()
4529 (interactive)
4530 (set-window-vscroll (selected-window)
4531 (+ 0.5 (window-vscroll)))))
4532 (global-set-key [A-up]
4533 #'(lambda ()
4534 (interactive)
4535 (set-window-vscroll (selected-window)
4536 (- (window-vscroll) 0.5)))))
4537
4538 ** New hook `fontification-functions'.
4539
4540 Functions from `fontification-functions' are called from redisplay
4541 when it encounters a region of text that is not yet fontified. This
4542 variable automatically becomes buffer-local when set. Each function
4543 is called with one argument, POS.
4544
4545 At least one of the hook functions should fontify one or more
4546 characters starting at POS in the current buffer. It should mark them
4547 as fontified by giving them a non-nil value of the `fontified' text
4548 property. It may be reasonable for these functions to check for the
4549 `fontified' property and not put it back on, but they do not have to.
4550
4551 ** Tool bar support.
4552
4553 Emacs supports a tool bar at the top of a frame under X. The frame
4554 parameter `tool-bar-lines' (X resource "toolBar", class "ToolBar")
4555 controls how may lines to reserve for the tool bar. A zero value
4556 suppresses the tool bar. If the value is non-zero and
4557 `auto-resize-tool-bars' is non-nil the tool bar's size will be changed
4558 automatically so that all tool bar items are visible.
4559
4560 *** Tool bar item definitions
4561
4562 Tool bar items are defined using `define-key' with a prefix-key
4563 `tool-bar'. For example `(define-key global-map [tool-bar item1] ITEM)'
4564 where ITEM is a list `(menu-item CAPTION BINDING PROPS...)'.
4565
4566 CAPTION is the caption of the item, If it's not a string, it is
4567 evaluated to get a string. The caption is currently not displayed in
4568 the tool bar, but it is displayed if the item doesn't have a `:help'
4569 property (see below).
4570
4571 BINDING is the tool bar item's binding. Tool bar items with keymaps as
4572 binding are currently ignored.
4573
4574 The following properties are recognized:
4575
4576 `:enable FORM'.
4577
4578 FORM is evaluated and specifies whether the tool bar item is enabled
4579 or disabled.
4580
4581 `:visible FORM'
4582
4583 FORM is evaluated and specifies whether the tool bar item is displayed.
4584
4585 `:filter FUNCTION'
4586
4587 FUNCTION is called with one parameter, the same list BINDING in which
4588 FUNCTION is specified as the filter. The value FUNCTION returns is
4589 used instead of BINDING to display this item.
4590
4591 `:button (TYPE SELECTED)'
4592
4593 TYPE must be one of `:radio' or `:toggle'. SELECTED is evaluated
4594 and specifies whether the button is selected (pressed) or not.
4595
4596 `:image IMAGES'
4597
4598 IMAGES is either a single image specification or a vector of four
4599 image specifications. If it is a vector, this table lists the
4600 meaning of each of the four elements:
4601
4602 Index Use when item is
4603 ----------------------------------------
4604 0 enabled and selected
4605 1 enabled and deselected
4606 2 disabled and selected
4607 3 disabled and deselected
4608
4609 If IMAGE is a single image specification, a Laplace edge-detection
4610 algorithm is used on that image to draw the image in disabled state.
4611
4612 `:help HELP-STRING'.
4613
4614 Gives a help string to display for the tool bar item. This help
4615 is displayed when the mouse is moved over the item.
4616
4617 The function `toolbar-add-item' is a convenience function for adding
4618 toolbar items generally, and `tool-bar-add-item-from-menu' can be used
4619 to define a toolbar item with a binding copied from an item on the
4620 menu bar.
4621
4622 The default bindings use a menu-item :filter to derive the tool-bar
4623 dynamically from variable `tool-bar-map' which may be set
4624 buffer-locally to override the global map.
4625
4626 *** Tool-bar-related variables.
4627
4628 If `auto-resize-tool-bar' is non-nil, the tool bar will automatically
4629 resize to show all defined tool bar items. It will never grow larger
4630 than 1/4 of the frame's size.
4631
4632 If `auto-raise-tool-bar-buttons' is non-nil, tool bar buttons will be
4633 raised when the mouse moves over them.
4634
4635 You can add extra space between tool bar items by setting
4636 `tool-bar-button-margin' to a positive integer specifying a number of
4637 pixels, or a pair of integers (X . Y) specifying horizontal and
4638 vertical margins . Default is 1.
4639
4640 You can change the shadow thickness of tool bar buttons by setting
4641 `tool-bar-button-relief' to an integer. Default is 3.
4642
4643 *** Tool-bar clicks with modifiers.
4644
4645 You can bind commands to clicks with control, shift, meta etc. on
4646 a tool bar item. If
4647
4648 (define-key global-map [tool-bar shell]
4649 '(menu-item "Shell" shell
4650 :image (image :type xpm :file "shell.xpm")))
4651
4652 is the original tool bar item definition, then
4653
4654 (define-key global-map [tool-bar S-shell] 'some-command)
4655
4656 makes a binding to run `some-command' for a shifted click on the same
4657 item.
4658
4659 ** Mode line changes.
4660
4661 *** Mouse-sensitive mode line.
4662
4663 The mode line can be made mouse-sensitive by displaying strings there
4664 that have a `local-map' text property. There are three ways to display
4665 a string with a `local-map' property in the mode line.
4666
4667 1. The mode line spec contains a variable whose string value has
4668 a `local-map' text property.
4669
4670 2. The mode line spec contains a format specifier (e.g. `%12b'), and
4671 that format specifier has a `local-map' property.
4672
4673 3. The mode line spec contains a list containing `:eval FORM'. FORM
4674 is evaluated. If the result is a string, and that string has a
4675 `local-map' property.
4676
4677 The same mechanism is used to determine the `face' and `help-echo'
4678 properties of strings in the mode line. See `bindings.el' for an
4679 example.
4680
4681 *** If a mode line element has the form `(:eval FORM)', FORM is
4682 evaluated and the result is used as mode line element.
4683
4684 *** You can suppress mode-line display by setting the buffer-local
4685 variable mode-line-format to nil.
4686
4687 *** A headerline can now be displayed at the top of a window.
4688
4689 This mode line's contents are controlled by the new variable
4690 `header-line-format' and `default-header-line-format' which are
4691 completely analogous to `mode-line-format' and
4692 `default-mode-line-format'. A value of nil means don't display a top
4693 line.
4694
4695 The appearance of top mode lines is controlled by the face
4696 `header-line'.
4697
4698 The function `coordinates-in-window-p' returns `header-line' for a
4699 position in the header-line.
4700
4701 ** Text property `display'
4702
4703 The `display' text property is used to insert images into text,
4704 replace text with other text, display text in marginal area, and it is
4705 also used to control other aspects of how text displays. The value of
4706 the `display' property should be a display specification, as described
4707 below, or a list or vector containing display specifications.
4708
4709 *** Replacing text, displaying text in marginal areas
4710
4711 To replace the text having the `display' property with some other
4712 text, use a display specification of the form `(LOCATION STRING)'.
4713
4714 If LOCATION is `(margin left-margin)', STRING is displayed in the left
4715 marginal area, if it is `(margin right-margin)', it is displayed in
4716 the right marginal area, and if LOCATION is `(margin nil)' STRING
4717 is displayed in the text. In the latter case you can also use the
4718 simpler form STRING as property value.
4719
4720 *** Variable width and height spaces
4721
4722 To display a space of fractional width or height, use a display
4723 specification of the form `(LOCATION STRECH)'. If LOCATION is
4724 `(margin left-margin)', the space is displayed in the left marginal
4725 area, if it is `(margin right-margin)', it is displayed in the right
4726 marginal area, and if LOCATION is `(margin nil)' the space is
4727 displayed in the text. In the latter case you can also use the
4728 simpler form STRETCH as property value.
4729
4730 The stretch specification STRETCH itself is a list of the form `(space
4731 PROPS)', where PROPS is a property list which can contain the
4732 properties described below.
4733
4734 The display of the fractional space replaces the display of the
4735 characters having the `display' property.
4736
4737 - :width WIDTH
4738
4739 Specifies that the space width should be WIDTH times the normal
4740 character width. WIDTH can be an integer or floating point number.
4741
4742 - :relative-width FACTOR
4743
4744 Specifies that the width of the stretch should be computed from the
4745 first character in a group of consecutive characters that have the
4746 same `display' property. The computation is done by multiplying the
4747 width of that character by FACTOR.
4748
4749 - :align-to HPOS
4750
4751 Specifies that the space should be wide enough to reach HPOS. The
4752 value HPOS is measured in units of the normal character width.
4753
4754 Exactly one of the above properties should be used.
4755
4756 - :height HEIGHT
4757
4758 Specifies the height of the space, as HEIGHT, measured in terms of the
4759 normal line height.
4760
4761 - :relative-height FACTOR
4762
4763 The height of the space is computed as the product of the height
4764 of the text having the `display' property and FACTOR.
4765
4766 - :ascent ASCENT
4767
4768 Specifies that ASCENT percent of the height of the stretch should be
4769 used for the ascent of the stretch, i.e. for the part above the
4770 baseline. The value of ASCENT must be a non-negative number less or
4771 equal to 100.
4772
4773 You should not use both `:height' and `:relative-height' together.
4774
4775 *** Images
4776
4777 A display specification for an image has the form `(LOCATION
4778 . IMAGE)', where IMAGE is an image specification. The image replaces,
4779 in the display, the characters having this display specification in
4780 their `display' text property. If LOCATION is `(margin left-margin)',
4781 the image will be displayed in the left marginal area, if it is
4782 `(margin right-margin)' it will be displayed in the right marginal
4783 area, and if LOCATION is `(margin nil)' the image will be displayed in
4784 the text. In the latter case you can also use the simpler form IMAGE
4785 as display specification.
4786
4787 *** Other display properties
4788
4789 - (space-width FACTOR)
4790
4791 Specifies that space characters in the text having that property
4792 should be displayed FACTOR times as wide as normal; FACTOR must be an
4793 integer or float.
4794
4795 - (height HEIGHT)
4796
4797 Display text having this property in a font that is smaller or larger.
4798
4799 If HEIGHT is a list of the form `(+ N)', where N is an integer, that
4800 means to use a font that is N steps larger. If HEIGHT is a list of
4801 the form `(- N)', that means to use a font that is N steps smaller. A
4802 ``step'' is defined by the set of available fonts; each size for which
4803 a font is available counts as a step.
4804
4805 If HEIGHT is a number, that means to use a font that is HEIGHT times
4806 as tall as the frame's default font.
4807
4808 If HEIGHT is a symbol, it is called as a function with the current
4809 height as argument. The function should return the new height to use.
4810
4811 Otherwise, HEIGHT is evaluated to get the new height, with the symbol
4812 `height' bound to the current specified font height.
4813
4814 - (raise FACTOR)
4815
4816 FACTOR must be a number, specifying a multiple of the current
4817 font's height. If it is positive, that means to display the characters
4818 raised. If it is negative, that means to display them lower down. The
4819 amount of raising or lowering is computed without taking account of the
4820 `height' subproperty.
4821
4822 *** Conditional display properties
4823
4824 All display specifications can be conditionalized. If a specification
4825 has the form `(when CONDITION . SPEC)', the specification SPEC applies
4826 only when CONDITION yields a non-nil value when evaluated. During the
4827 evaluation, `object' is bound to the string or buffer having the
4828 conditional display property; `position' and `buffer-position' are
4829 bound to the position within `object' and the buffer position where
4830 the display property was found, respectively. Both positions can be
4831 different when object is a string.
4832
4833 The normal specification consisting of SPEC only is equivalent to
4834 `(when t . SPEC)'.
4835
4836 ** New menu separator types.
4837
4838 Emacs now supports more than one menu separator type. Menu items with
4839 item names consisting of dashes only (including zero dashes) are
4840 treated like before. In addition, the following item names are used
4841 to specify other menu separator types.
4842
4843 - `--no-line' or `--space', or `--:space', or `--:noLine'
4844
4845 No separator lines are drawn, but a small space is inserted where the
4846 separator occurs.
4847
4848 - `--single-line' or `--:singleLine'
4849
4850 A single line in the menu's foreground color.
4851
4852 - `--double-line' or `--:doubleLine'
4853
4854 A double line in the menu's foreground color.
4855
4856 - `--single-dashed-line' or `--:singleDashedLine'
4857
4858 A single dashed line in the menu's foreground color.
4859
4860 - `--double-dashed-line' or `--:doubleDashedLine'
4861
4862 A double dashed line in the menu's foreground color.
4863
4864 - `--shadow-etched-in' or `--:shadowEtchedIn'
4865
4866 A single line with 3D sunken appearance. This is the form
4867 displayed for item names consisting of dashes only.
4868
4869 - `--shadow-etched-out' or `--:shadowEtchedOut'
4870
4871 A single line with 3D raised appearance.
4872
4873 - `--shadow-etched-in-dash' or `--:shadowEtchedInDash'
4874
4875 A single dashed line with 3D sunken appearance.
4876
4877 - `--shadow-etched-out-dash' or `--:shadowEtchedOutDash'
4878
4879 A single dashed line with 3D raise appearance.
4880
4881 - `--shadow-double-etched-in' or `--:shadowDoubleEtchedIn'
4882
4883 Two lines with 3D sunken appearance.
4884
4885 - `--shadow-double-etched-out' or `--:shadowDoubleEtchedOut'
4886
4887 Two lines with 3D raised appearance.
4888
4889 - `--shadow-double-etched-in-dash' or `--:shadowDoubleEtchedInDash'
4890
4891 Two dashed lines with 3D sunken appearance.
4892
4893 - `--shadow-double-etched-out-dash' or `--:shadowDoubleEtchedOutDash'
4894
4895 Two dashed lines with 3D raised appearance.
4896
4897 Under LessTif/Motif, the last four separator types are displayed like
4898 the corresponding single-line separators.
4899
4900 ** New frame parameters for scroll bar colors.
4901
4902 The new frame parameters `scroll-bar-foreground' and
4903 `scroll-bar-background' can be used to change scroll bar colors.
4904 Their value must be either a color name, a string, or nil to specify
4905 that scroll bars should use a default color. For toolkit scroll bars,
4906 default colors are toolkit specific. For non-toolkit scroll bars, the
4907 default background is the background color of the frame, and the
4908 default foreground is black.
4909
4910 The X resource name of these parameters are `scrollBarForeground'
4911 (class ScrollBarForeground) and `scrollBarBackground' (class
4912 `ScrollBarBackground').
4913
4914 Setting these parameters overrides toolkit specific X resource
4915 settings for scroll bar colors.
4916
4917 ** You can set `redisplay-dont-pause' to a non-nil value to prevent
4918 display updates from being interrupted when input is pending.
4919
4920 ** Changing a window's width may now change its window start if it
4921 starts on a continuation line. The new window start is computed based
4922 on the window's new width, starting from the start of the continued
4923 line as the start of the screen line with the minimum distance from
4924 the original window start.
4925
4926 ** The variable `hscroll-step' and the functions
4927 `hscroll-point-visible' and `hscroll-window-column' have been removed
4928 now that proper horizontal scrolling is implemented.
4929
4930 ** Windows can now be made fixed-width and/or fixed-height.
4931
4932 A window is fixed-size if its buffer has a buffer-local variable
4933 `window-size-fixed' whose value is not nil. A value of `height' makes
4934 windows fixed-height, a value of `width' makes them fixed-width, any
4935 other non-nil value makes them both fixed-width and fixed-height.
4936
4937 The following code makes all windows displaying the current buffer
4938 fixed-width and fixed-height.
4939
4940 (set (make-local-variable 'window-size-fixed) t)
4941
4942 A call to enlarge-window on a window gives an error if that window is
4943 fixed-width and it is tried to change the window's width, or if the
4944 window is fixed-height, and it is tried to change its height. To
4945 change the size of a fixed-size window, bind `window-size-fixed'
4946 temporarily to nil, for example
4947
4948 (let ((window-size-fixed nil))
4949 (enlarge-window 10))
4950
4951 Likewise, an attempt to split a fixed-height window vertically,
4952 or a fixed-width window horizontally results in a error.
4953
4954 ** The cursor-type frame parameter is now supported on MS-DOS
4955 terminals. When Emacs starts, it by default changes the cursor shape
4956 to a solid box, as it does on Unix. The `cursor-type' frame parameter
4957 overrides this as it does on Unix, except that the bar cursor is
4958 horizontal rather than vertical (since the MS-DOS display doesn't
4959 support a vertical-bar cursor).
4960
4961
4962 \f
4963 * Emacs 20.7 is a bug-fix release with few user-visible changes
4964
4965 ** It is now possible to use CCL-based coding systems for keyboard
4966 input.
4967
4968 ** ange-ftp now handles FTP security extensions, like Kerberos.
4969
4970 ** Rmail has been extended to recognize more forms of digest messages.
4971
4972 ** Now, most coding systems set in keyboard coding system work not
4973 only for character input, but also in incremental search. The
4974 exceptions are such coding systems that handle 2-byte character sets
4975 (e.g euc-kr, euc-jp) and that use ISO's escape sequence
4976 (e.g. iso-2022-jp). They are ignored in incremental search.
4977
4978 ** Support for Macintosh PowerPC-based machines running GNU/Linux has
4979 been added.
4980
4981 \f
4982 * Emacs 20.6 is a bug-fix release with one user-visible change
4983
4984 ** Support for ARM-based non-RISCiX machines has been added.
4985
4986
4987 \f
4988 * Emacs 20.5 is a bug-fix release with no user-visible changes.
4989
4990 ** Not new, but not mentioned before:
4991 M-w when Transient Mark mode is enabled disables the mark.
4992 \f
4993 * Changes in Emacs 20.4
4994
4995 ** Init file may be called .emacs.el.
4996
4997 You can now call the Emacs init file `.emacs.el'.
4998 Formerly the name had to be `.emacs'. If you use the name
4999 `.emacs.el', you can byte-compile the file in the usual way.
5000
5001 If both `.emacs' and `.emacs.el' exist, the latter file
5002 is the one that is used.
5003
5004 ** shell-command, and shell-command-on-region, now return
5005 the exit code of the command (unless it is asynchronous).
5006 Also, you can specify a place to put the error output,
5007 separate from the command's regular output.
5008 Interactively, the variable shell-command-default-error-buffer
5009 says where to put error output; set it to a buffer name.
5010 In calls from Lisp, an optional argument ERROR-BUFFER specifies
5011 the buffer name.
5012
5013 When you specify a non-nil error buffer (or buffer name), any error
5014 output is inserted before point in that buffer, with \f\n to separate
5015 it from the previous batch of error output. The error buffer is not
5016 cleared, so error output from successive commands accumulates there.
5017
5018 ** Setting the default value of enable-multibyte-characters to nil in
5019 the .emacs file, either explicitly using setq-default, or via Custom,
5020 is now essentially equivalent to using --unibyte: all buffers
5021 created during startup will be made unibyte after loading .emacs.
5022
5023 ** C-x C-f now handles the wildcards * and ? in file names. For
5024 example, typing C-x C-f c*.c RET visits all the files whose names
5025 match c*.c. To visit a file whose name contains * or ?, add the
5026 quoting sequence /: to the beginning of the file name.
5027
5028 ** The M-x commands keep-lines, flush-lines and count-matches
5029 now have the same feature as occur and query-replace:
5030 if the pattern contains any upper case letters, then
5031 they never ignore case.
5032
5033 ** The end-of-line format conversion feature previously mentioned
5034 under `* Emacs 20.1 changes for MS-DOS and MS-Windows' actually
5035 applies to all operating systems. Emacs recognizes from the contents
5036 of a file what convention it uses to separate lines--newline, CRLF, or
5037 just CR--and automatically converts the contents to the normal Emacs
5038 convention (using newline to separate lines) for editing. This is a
5039 part of the general feature of coding system conversion.
5040
5041 If you subsequently save the buffer, Emacs converts the text back to
5042 the same format that was used in the file before.
5043
5044 You can turn off end-of-line conversion by setting the variable
5045 `inhibit-eol-conversion' to non-nil, e.g. with Custom in the MULE group.
5046
5047 ** The character set property `prefered-coding-system' has been
5048 renamed to `preferred-coding-system', for the sake of correct spelling.
5049 This is a fairly internal feature, so few programs should be affected.
5050
5051 ** Mode-line display of end-of-line format is changed.
5052 The indication of the end-of-line format of the file visited by a
5053 buffer is now more explicit when that format is not the usual one for
5054 your operating system. For example, the DOS-style end-of-line format
5055 is displayed as "(DOS)" on Unix and GNU/Linux systems. The usual
5056 end-of-line format is still displayed as a single character (colon for
5057 Unix, backslash for DOS and Windows, and forward slash for the Mac).
5058
5059 The values of the variables eol-mnemonic-unix, eol-mnemonic-dos,
5060 eol-mnemonic-mac, and eol-mnemonic-undecided, which are strings,
5061 control what is displayed in the mode line for each end-of-line
5062 format. You can now customize these variables.
5063
5064 ** In the previous version of Emacs, tar-mode didn't work well if a
5065 filename contained non-ASCII characters. Now this is fixed. Such a
5066 filename is decoded by file-name-coding-system if the default value of
5067 enable-multibyte-characters is non-nil.
5068
5069 ** The command temp-buffer-resize-mode toggles a minor mode
5070 in which temporary buffers (such as help buffers) are given
5071 windows just big enough to hold the whole contents.
5072
5073 ** If you use completion.el, you must now run the function
5074 dynamic-completion-mode to enable it. Just loading the file
5075 doesn't have any effect.
5076
5077 ** In Flyspell mode, the default is now to make just one Ispell process,
5078 not one per buffer.
5079
5080 ** If you use iswitchb but do not call (iswitchb-default-keybindings) to
5081 use the default keybindings, you will need to add the following line:
5082 (add-hook 'minibuffer-setup-hook 'iswitchb-minibuffer-setup)
5083
5084 ** Auto-show mode is no longer enabled just by loading auto-show.el.
5085 To control it, set `auto-show-mode' via Custom or use the
5086 `auto-show-mode' command.
5087
5088 ** Handling of X fonts' ascent/descent parameters has been changed to
5089 avoid redisplay problems. As a consequence, compared with previous
5090 versions the line spacing and frame size now differ with some font
5091 choices, typically increasing by a pixel per line. This change
5092 occurred in version 20.3 but was not documented then.
5093
5094 ** If you select the bar cursor style, it uses the frame's
5095 cursor-color, rather than the cursor foreground pixel.
5096
5097 ** In multibyte mode, Rmail decodes incoming MIME messages using the
5098 character set specified in the message. If you want to disable this
5099 feature, set the variable rmail-decode-mime-charset to nil.
5100
5101 ** Not new, but not mentioned previously in NEWS: when you use #! at
5102 the beginning of a file to make it executable and specify an
5103 interpreter program, Emacs looks on the second line for the -*- mode
5104 and variable specification, as well as on the first line.
5105
5106 ** Support for IBM codepage encoding of non-ASCII characters.
5107
5108 The new command M-x codepage-setup creates a special coding system
5109 that can be used to convert text between a specific IBM codepage and
5110 one of the character sets built into Emacs which matches that
5111 codepage. For example, codepage 850 corresponds to Latin-1 character
5112 set, codepage 855 corresponds to Cyrillic-ISO character set, etc.
5113
5114 Windows codepages 1250, 1251 and some others, where Windows deviates
5115 from the corresponding ISO character set, are also supported.
5116
5117 IBM box-drawing characters and other glyphs which don't have
5118 equivalents in the corresponding ISO character set, are converted to
5119 a character defined by dos-unsupported-char-glyph on MS-DOS, and to
5120 `?' on other systems.
5121
5122 IBM codepages are widely used on MS-DOS and MS-Windows, so this
5123 feature is most useful on those platforms, but it can also be used on
5124 Unix.
5125
5126 Emacs compiled for MS-DOS automatically loads the support for the
5127 current codepage when it starts.
5128
5129 ** Mail changes
5130
5131 *** When mail is sent using compose-mail (C-x m), and if
5132 `mail-send-nonascii' is set to the new default value `mime',
5133 appropriate MIME headers are added. The headers are added only if
5134 non-ASCII characters are present in the body of the mail, and no other
5135 MIME headers are already present. For example, the following three
5136 headers are added if the coding system used in the *mail* buffer is
5137 latin-1:
5138
5139 MIME-version: 1.0
5140 Content-type: text/plain; charset=iso-8859-1
5141 Content-Transfer-Encoding: 8bit
5142
5143 *** The new variable default-sendmail-coding-system specifies the
5144 default way to encode outgoing mail. This has higher priority than
5145 default-buffer-file-coding-system but has lower priority than
5146 sendmail-coding-system and the local value of
5147 buffer-file-coding-system.
5148
5149 You should not set this variable manually. Instead, set
5150 sendmail-coding-system to specify a fixed encoding for all outgoing
5151 mail.
5152
5153 *** When you try to send a message that contains non-ASCII characters,
5154 if the coding system specified by those variables doesn't handle them,
5155 Emacs will ask you to select a suitable coding system while showing a
5156 list of possible coding systems.
5157
5158 ** CC Mode changes
5159
5160 *** c-default-style can now take an association list that maps major
5161 modes to style names. When this variable is an alist, Java mode no
5162 longer hardcodes a setting to "java" style. See the variable's
5163 docstring for details.
5164
5165 *** It's now possible to put a list as the offset on a syntactic
5166 symbol. The list is evaluated recursively until a non-nil offset is
5167 found. This is useful to combine several lineup functions to act in a
5168 prioritized order on a single line. However, none of the supplied
5169 lineup functions use this feature currently.
5170
5171 *** New syntactic symbol catch-clause, which is used on the "catch" and
5172 "finally" lines in try-catch constructs in C++ and Java.
5173
5174 *** New cleanup brace-catch-brace on c-cleanup-list, which does for
5175 "catch" lines what brace-elseif-brace does for "else if" lines.
5176
5177 *** The braces of Java anonymous inner classes are treated separately
5178 from the braces of other classes in auto-newline mode. Two new
5179 symbols inexpr-class-open and inexpr-class-close may be used on
5180 c-hanging-braces-alist to control the automatic newlines used for
5181 anonymous classes.
5182
5183 *** Support for the Pike language added, along with new Pike specific
5184 syntactic symbols: inlambda, lambda-intro-cont
5185
5186 *** Support for Java anonymous classes via new syntactic symbol
5187 inexpr-class. New syntactic symbol inexpr-statement for Pike
5188 support and gcc-style statements inside expressions. New lineup
5189 function c-lineup-inexpr-block.
5190
5191 *** New syntactic symbol brace-entry-open which is used in brace lists
5192 (i.e. static initializers) when a list entry starts with an open
5193 brace. These used to be recognized as brace-list-entry's.
5194 c-electric-brace also recognizes brace-entry-open braces
5195 (brace-list-entry's can no longer be electrified).
5196
5197 *** New command c-indent-line-or-region, not bound by default.
5198
5199 *** `#' is only electric when typed in the indentation of a line.
5200
5201 *** Parentheses are now electric (via the new command c-electric-paren)
5202 for auto-reindenting lines when parens are typed.
5203
5204 *** In "gnu" style, inline-open offset is now set to zero.
5205
5206 *** Uniform handling of the inclass syntactic symbol. The indentation
5207 associated with it is now always relative to the class opening brace.
5208 This means that the indentation behavior has changed in some
5209 circumstances, but only if you've put anything besides 0 on the
5210 class-open syntactic symbol (none of the default styles do that).
5211
5212 ** Gnus changes.
5213
5214 *** New functionality for using Gnus as an offline newsreader has been
5215 added. A plethora of new commands and modes have been added. See the
5216 Gnus manual for the full story.
5217
5218 *** The nndraft backend has returned, but works differently than
5219 before. All Message buffers are now also articles in the nndraft
5220 group, which is created automatically.
5221
5222 *** `gnus-alter-header-function' can now be used to alter header
5223 values.
5224
5225 *** `gnus-summary-goto-article' now accept Message-ID's.
5226
5227 *** A new Message command for deleting text in the body of a message
5228 outside the region: `C-c C-v'.
5229
5230 *** You can now post to component group in nnvirtual groups with
5231 `C-u C-c C-c'.
5232
5233 *** `nntp-rlogin-program' -- new variable to ease customization.
5234
5235 *** `C-u C-c C-c' in `gnus-article-edit-mode' will now inhibit
5236 re-highlighting of the article buffer.
5237
5238 *** New element in `gnus-boring-article-headers' -- `long-to'.
5239
5240 *** `M-i' symbolic prefix command. See the section "Symbolic
5241 Prefixes" in the Gnus manual for details.
5242
5243 *** `L' and `I' in the summary buffer now take the symbolic prefix
5244 `a' to add the score rule to the "all.SCORE" file.
5245
5246 *** `gnus-simplify-subject-functions' variable to allow greater
5247 control over simplification.
5248
5249 *** `A T' -- new command for fetching the current thread.
5250
5251 *** `/ T' -- new command for including the current thread in the
5252 limit.
5253
5254 *** `M-RET' is a new Message command for breaking cited text.
5255
5256 *** \\1-expressions are now valid in `nnmail-split-methods'.
5257
5258 *** The `custom-face-lookup' function has been removed.
5259 If you used this function in your initialization files, you must
5260 rewrite them to use `face-spec-set' instead.
5261
5262 *** Canceling now uses the current select method. Symbolic prefix
5263 `a' forces normal posting method.
5264
5265 *** New command to translate M******** sm*rtq**t*s into proper text
5266 -- `W d'.
5267
5268 *** For easier debugging of nntp, you can set `nntp-record-commands'
5269 to a non-nil value.
5270
5271 *** nntp now uses ~/.authinfo, a .netrc-like file, for controlling
5272 where and how to send AUTHINFO to NNTP servers.
5273
5274 *** A command for editing group parameters from the summary buffer
5275 has been added.
5276
5277 *** A history of where mails have been split is available.
5278
5279 *** A new article date command has been added -- `article-date-iso8601'.
5280
5281 *** Subjects can be simplified when threading by setting
5282 `gnus-score-thread-simplify'.
5283
5284 *** A new function for citing in Message has been added --
5285 `message-cite-original-without-signature'.
5286
5287 *** `article-strip-all-blank-lines' -- new article command.
5288
5289 *** A new Message command to kill to the end of the article has
5290 been added.
5291
5292 *** A minimum adaptive score can be specified by using the
5293 `gnus-adaptive-word-minimum' variable.
5294
5295 *** The "lapsed date" article header can be kept continually
5296 updated by the `gnus-start-date-timer' command.
5297
5298 *** Web listserv archives can be read with the nnlistserv backend.
5299
5300 *** Old dejanews archives can now be read by nnweb.
5301
5302 *** `gnus-posting-styles' has been re-activated.
5303
5304 ** Changes to TeX and LaTeX mode
5305
5306 *** The new variable `tex-start-options-string' can be used to give
5307 options for the TeX run. The default value causes TeX to run in
5308 nonstopmode. For an interactive TeX run set it to nil or "".
5309
5310 *** The command `tex-feed-input' sends input to the Tex Shell. In a
5311 TeX buffer it is bound to the keys C-RET, C-c RET, and C-c C-m (some
5312 of these keys may not work on all systems). For instance, if you run
5313 TeX interactively and if the TeX run stops because of an error, you
5314 can continue it without leaving the TeX buffer by typing C-RET.
5315
5316 *** The Tex Shell Buffer is now in `compilation-shell-minor-mode'.
5317 All error-parsing commands of the Compilation major mode are available
5318 but bound to keys that don't collide with the shell. Thus you can use
5319 the Tex Shell for command line executions like a usual shell.
5320
5321 *** The commands `tex-validate-region' and `tex-validate-buffer' check
5322 the matching of braces and $'s. The errors are listed in a *Occur*
5323 buffer and you can use C-c C-c or mouse-2 to go to a particular
5324 mismatch.
5325
5326 ** Changes to RefTeX mode
5327
5328 *** The table of contents buffer can now also display labels and
5329 file boundaries in addition to sections. Use `l', `i', and `c' keys.
5330
5331 *** Labels derived from context (the section heading) are now
5332 lowercase by default. To make the label legal in LaTeX, latin-1
5333 characters will lose their accent. All Mule characters will be
5334 removed from the label.
5335
5336 *** The automatic display of cross reference information can also use
5337 a window instead of the echo area. See variable `reftex-auto-view-crossref'.
5338
5339 *** kpsewhich can be used by RefTeX to find TeX and BibTeX files. See the
5340 customization group `reftex-finding-files'.
5341
5342 *** The option `reftex-bibfile-ignore-list' has been renamed to
5343 `reftex-bibfile-ignore-regexps' and indeed can be fed with regular
5344 expressions.
5345
5346 *** Multiple Selection buffers are now hidden buffers.
5347
5348 ** New/deleted modes and packages
5349
5350 *** The package snmp-mode.el provides major modes for editing SNMP and
5351 SNMPv2 MIBs. It has entries on `auto-mode-alist'.
5352
5353 *** The package sql.el provides a major mode, M-x sql-mode, for
5354 editing SQL files, and M-x sql-interactive-mode for interacting with
5355 SQL interpreters. It has an entry on `auto-mode-alist'.
5356
5357 *** M-x highlight-changes-mode provides a minor mode displaying buffer
5358 changes with a special face.
5359
5360 *** ispell4.el has been deleted. It got in the way of ispell.el and
5361 this was hard to fix reliably. It has long been obsolete -- use
5362 Ispell 3.1 and ispell.el.
5363 \f
5364 * MS-DOS changes in Emacs 20.4
5365
5366 ** Emacs compiled for MS-DOS now supports MULE features better.
5367 This includes support for display of all ISO 8859-N character sets,
5368 conversion to and from IBM codepage encoding of non-ASCII characters,
5369 and automatic setup of the MULE environment at startup. For details,
5370 check out the section `MS-DOS and MULE' in the manual.
5371
5372 The MS-DOS installation procedure automatically configures and builds
5373 Emacs with input method support if it finds an unpacked Leim
5374 distribution when the config.bat script is run.
5375
5376 ** Formerly, the value of lpr-command did not affect printing on
5377 MS-DOS unless print-region-function was set to nil, but now it
5378 controls whether an external program is invoked or output is written
5379 directly to a printer port. Similarly, in the previous version of
5380 Emacs, the value of ps-lpr-command did not affect PostScript printing
5381 on MS-DOS unless ps-printer-name was set to something other than a
5382 string (eg. t or `pipe'), but now it controls whether an external
5383 program is used. (These changes were made so that configuration of
5384 printing variables would be almost identical across all platforms.)
5385
5386 ** In the previous version of Emacs, PostScript and non-PostScript
5387 output was piped to external programs, but because most print programs
5388 available for MS-DOS and MS-Windows cannot read data from their standard
5389 input, on those systems the data to be output is now written to a
5390 temporary file whose name is passed as the last argument to the external
5391 program.
5392
5393 An exception is made for `print', a standard program on Windows NT,
5394 and `nprint', a standard program on Novell Netware. For both of these
5395 programs, the command line is constructed in the appropriate syntax
5396 automatically, using only the value of printer-name or ps-printer-name
5397 as appropriate--the value of the relevant `-switches' variable is
5398 ignored, as both programs have no useful switches.
5399
5400 ** The value of the variable dos-printer (cf. dos-ps-printer), if it has
5401 a value, overrides the value of printer-name (cf. ps-printer-name), on
5402 MS-DOS and MS-Windows only. This has been true since version 20.3, but
5403 was not documented clearly before.
5404
5405 ** All the Emacs games now work on MS-DOS terminals.
5406 This includes Tetris and Snake.
5407 \f
5408 * Lisp changes in Emacs 20.4
5409
5410 ** New functions line-beginning-position and line-end-position
5411 return the position of the beginning or end of the current line.
5412 They both accept an optional argument, which has the same
5413 meaning as the argument to beginning-of-line or end-of-line.
5414
5415 ** find-file and allied functions now have an optional argument
5416 WILDCARD. If this is non-nil, they do wildcard processing,
5417 and visit all files that match the wildcard pattern.
5418
5419 ** Changes in the file-attributes function.
5420
5421 *** The file size returned by file-attributes may be an integer or a float.
5422 It is an integer if the size fits in a Lisp integer, float otherwise.
5423
5424 *** The inode number returned by file-attributes may be an integer (if
5425 the number fits in a Lisp integer) or a cons cell containing two
5426 integers.
5427
5428 ** The new function directory-files-and-attributes returns a list of
5429 files in a directory and their attributes. It accepts the same
5430 arguments as directory-files and has similar semantics, except that
5431 file names and attributes are returned.
5432
5433 ** The new function file-attributes-lessp is a helper function for
5434 sorting the list generated by directory-files-and-attributes. It
5435 accepts two arguments, each a list of a file name and its attributes.
5436 It compares the file names of each according to string-lessp and
5437 returns the result.
5438
5439 ** The new function file-expand-wildcards expands a wildcard-pattern
5440 to produce a list of existing files that match the pattern.
5441
5442 ** New functions for base64 conversion:
5443
5444 The function base64-encode-region converts a part of the buffer
5445 into the base64 code used in MIME. base64-decode-region
5446 performs the opposite conversion. Line-breaking is supported
5447 optionally.
5448
5449 Functions base64-encode-string and base64-decode-string do a similar
5450 job on the text in a string. They return the value as a new string.
5451
5452 **
5453 The new function process-running-child-p
5454 will tell you if a subprocess has given control of its
5455 terminal to its own child process.
5456
5457 ** interrupt-process and such functions have a new feature:
5458 when the second argument is `lambda', they send a signal
5459 to the running child of the subshell, if any, but if the shell
5460 itself owns its terminal, no signal is sent.
5461
5462 ** There are new widget types `plist' and `alist' which can
5463 be used for customizing variables whose values are plists or alists.
5464
5465 ** easymenu.el Now understands `:key-sequence' and `:style button'.
5466 :included is an alias for :visible.
5467
5468 easy-menu-add-item now understands the values returned by
5469 easy-menu-remove-item and easy-menu-item-present-p. This can be used
5470 to move or copy menu entries.
5471
5472 ** Multibyte editing changes
5473
5474 *** The definitions of sref and char-bytes are changed. Now, sref is
5475 an alias of aref and char-bytes always returns 1. This change is to
5476 make some Emacs Lisp code which works on 20.2 and earlier also
5477 work on the latest Emacs. Such code uses a combination of sref and
5478 char-bytes in a loop typically as below:
5479 (setq char (sref str idx)
5480 idx (+ idx (char-bytes idx)))
5481 The byte-compiler now warns that this is obsolete.
5482
5483 If you want to know how many bytes a specific multibyte character
5484 (say, CH) occupies in a multibyte buffer, use this code:
5485 (charset-bytes (char-charset ch))
5486
5487 *** In multibyte mode, when you narrow a buffer to some region, and the
5488 region is preceded or followed by non-ASCII codes, inserting or
5489 deleting at the head or the end of the region may signal this error:
5490
5491 Byte combining across boundary of accessible buffer text inhibited
5492
5493 This is to avoid some bytes being combined together into a character
5494 across the boundary.
5495
5496 *** The functions find-charset-region and find-charset-string include
5497 `unknown' in the returned list in the following cases:
5498 o The current buffer or the target string is unibyte and
5499 contains 8-bit characters.
5500 o The current buffer or the target string is multibyte and
5501 contains invalid characters.
5502
5503 *** The functions decode-coding-region and encode-coding-region remove
5504 text properties of the target region. Ideally, they should correctly
5505 preserve text properties, but for the moment, it's hard. Removing
5506 text properties is better than preserving them in a less-than-correct
5507 way.
5508
5509 *** prefer-coding-system sets EOL conversion of default coding systems.
5510 If the argument to prefer-coding-system specifies a certain type of
5511 end of line conversion, the default coding systems set by
5512 prefer-coding-system will specify that conversion type for end of line.
5513
5514 *** The new function thai-compose-string can be used to properly
5515 compose Thai characters in a string.
5516
5517 ** The primitive `define-prefix-command' now takes an optional third
5518 argument NAME, which should be a string. It supplies the menu name
5519 for the created keymap. Keymaps created in order to be displayed as
5520 menus should always use the third argument.
5521
5522 ** The meanings of optional second arguments for read-char,
5523 read-event, and read-char-exclusive are flipped. Now the second
5524 arguments are INHERIT-INPUT-METHOD. These functions use the current
5525 input method (if any) if and only if INHERIT-INPUT-METHOD is non-nil.
5526
5527 ** The new function clear-this-command-keys empties out the contents
5528 of the vector that (this-command-keys) returns. This is useful in
5529 programs that read passwords, to prevent the passwords from echoing
5530 inadvertently as part of the next command in certain cases.
5531
5532 ** The new macro `with-temp-message' displays a temporary message in
5533 the echo area, while executing some Lisp code. Like `progn', it
5534 returns the value of the last form, but it also restores the previous
5535 echo area contents.
5536
5537 (with-temp-message MESSAGE &rest BODY)
5538
5539 ** The function `require' now takes an optional third argument
5540 NOERROR. If it is non-nil, then there is no error if the
5541 requested feature cannot be loaded.
5542
5543 ** In the function modify-face, an argument of (nil) for the
5544 foreground color, background color or stipple pattern
5545 means to clear out that attribute.
5546
5547 ** The `outer-window-id' frame property of an X frame
5548 gives the window number of the outermost X window for the frame.
5549
5550 ** Temporary buffers made with with-output-to-temp-buffer are now
5551 read-only by default, and normally use the major mode Help mode
5552 unless you put them in some other non-Fundamental mode before the
5553 end of with-output-to-temp-buffer.
5554
5555 ** The new functions gap-position and gap-size return information on
5556 the gap of the current buffer.
5557
5558 ** The new functions position-bytes and byte-to-position provide a way
5559 to convert between character positions and byte positions in the
5560 current buffer.
5561
5562 ** vc.el defines two new macros, `edit-vc-file' and `with-vc-file', to
5563 facilitate working with version-controlled files from Lisp programs.
5564 These macros check out a given file automatically if needed, and check
5565 it back in after any modifications have been made.
5566 \f
5567 * Installation Changes in Emacs 20.3
5568
5569 ** The default value of load-path now includes most subdirectories of
5570 the site-specific directories /usr/local/share/emacs/site-lisp and
5571 /usr/local/share/emacs/VERSION/site-lisp, in addition to those
5572 directories themselves. Both immediate subdirectories and
5573 subdirectories multiple levels down are added to load-path.
5574
5575 Not all subdirectories are included, though. Subdirectories whose
5576 names do not start with a letter or digit are excluded.
5577 Subdirectories named RCS or CVS are excluded. Also, a subdirectory
5578 which contains a file named `.nosearch' is excluded. You can use
5579 these methods to prevent certain subdirectories from being searched.
5580
5581 Emacs finds these subdirectories and adds them to load-path when it
5582 starts up. While it would be cleaner to find the subdirectories each
5583 time Emacs loads a file, that would be much slower.
5584
5585 This feature is an incompatible change. If you have stored some Emacs
5586 Lisp files in a subdirectory of the site-lisp directory specifically
5587 to prevent them from being used, you will need to rename the
5588 subdirectory to start with a non-alphanumeric character, or create a
5589 `.nosearch' file in it, in order to continue to achieve the desired
5590 results.
5591
5592 ** Emacs no longer includes an old version of the C preprocessor from
5593 GCC. This was formerly used to help compile Emacs with C compilers
5594 that had limits on the significant length of an identifier, but in
5595 fact we stopped supporting such compilers some time ago.
5596 \f
5597 * Changes in Emacs 20.3
5598
5599 ** The new command C-x z (repeat) repeats the previous command
5600 including its argument. If you repeat the z afterward,
5601 it repeats the command additional times; thus, you can
5602 perform many repetitions with one keystroke per repetition.
5603
5604 ** Emacs now supports "selective undo" which undoes only within a
5605 specified region. To do this, set point and mark around the desired
5606 region and type C-u C-x u (or C-u C-_). You can then continue undoing
5607 further, within the same region, by repeating the ordinary undo
5608 command C-x u or C-_. This will keep undoing changes that were made
5609 within the region you originally specified, until either all of them
5610 are undone, or it encounters a change which crosses the edge of that
5611 region.
5612
5613 In Transient Mark mode, undoing when a region is active requests
5614 selective undo.
5615
5616 ** If you specify --unibyte when starting Emacs, then all buffers are
5617 unibyte, except when a Lisp program specifically creates a multibyte
5618 buffer. Setting the environment variable EMACS_UNIBYTE has the same
5619 effect. The --no-unibyte option overrides EMACS_UNIBYTE and directs
5620 Emacs to run normally in multibyte mode.
5621
5622 The option --unibyte does not affect the reading of Emacs Lisp files,
5623 though. If you want a Lisp file to be read in unibyte mode, use
5624 -*-unibyte: t;-*- on its first line. That will force Emacs to
5625 load that file in unibyte mode, regardless of how Emacs was started.
5626
5627 ** toggle-enable-multibyte-characters no longer has a key binding and
5628 no longer appears in the menu bar. We've realized that changing the
5629 enable-multibyte-characters variable in an existing buffer is
5630 something that most users not do.
5631
5632 ** You can specify a coding system to use for the next cut or paste
5633 operations through the window system with the command C-x RET X.
5634 The coding system can make a difference for communication with other
5635 applications.
5636
5637 C-x RET x specifies a coding system for all subsequent cutting and
5638 pasting operations.
5639
5640 ** You can specify the printer to use for commands that do printing by
5641 setting the variable `printer-name'. Just what a printer name looks
5642 like depends on your operating system. You can specify a different
5643 printer for the Postscript printing commands by setting
5644 `ps-printer-name'.
5645
5646 ** Emacs now supports on-the-fly spell checking by the means of a
5647 minor mode. It is called M-x flyspell-mode. You don't have to remember
5648 any other special commands to use it, and you will hardly notice it
5649 except when you make a spelling error. Flyspell works by highlighting
5650 incorrect words as soon as they are completed or as soon as the cursor
5651 hits a new word.
5652
5653 Flyspell mode works with whichever dictionary you have selected for
5654 Ispell in Emacs. In TeX mode, it understands TeX syntax so as not
5655 to be confused by TeX commands.
5656
5657 You can correct a misspelled word by editing it into something
5658 correct. You can also correct it, or accept it as correct, by
5659 clicking on the word with Mouse-2; that gives you a pop-up menu
5660 of various alternative replacements and actions.
5661
5662 Flyspell mode also proposes "automatic" corrections. M-TAB replaces
5663 the current misspelled word with a possible correction. If several
5664 corrections are made possible, M-TAB cycles through them in
5665 alphabetical order, or in order of decreasing likelihood if
5666 flyspell-sort-corrections is nil.
5667
5668 Flyspell mode also flags an error when a word is repeated, if
5669 flyspell-mark-duplications-flag is non-nil.
5670
5671 ** Changes in input method usage.
5672
5673 Now you can use arrow keys (right, left, down, up) for selecting among
5674 the alternatives just the same way as you do by C-f, C-b, C-n, and C-p
5675 respectively.
5676
5677 You can use the ENTER key to accept the current conversion.
5678
5679 If you type TAB to display a list of alternatives, you can select one
5680 of the alternatives with Mouse-2.
5681
5682 The meaning of the variable `input-method-verbose-flag' is changed so
5683 that you can set it to t, nil, `default', or `complex-only'.
5684
5685 If the value is nil, extra guidance is never given.
5686
5687 If the value is t, extra guidance is always given.
5688
5689 If the value is `complex-only', extra guidance is always given only
5690 when you are using complex input methods such as chinese-py.
5691
5692 If the value is `default' (this is the default), extra guidance is
5693 given in the following case:
5694 o When you are using a complex input method.
5695 o When you are using a simple input method but not in the minibuffer.
5696
5697 If you are using Emacs through a very slow line, setting
5698 input-method-verbose-flag to nil or to complex-only is a good choice,
5699 and if you are using an input method you are not familiar with,
5700 setting it to t is helpful.
5701
5702 The old command select-input-method is now called set-input-method.
5703
5704 In the language environment "Korean", you can use the following
5705 keys:
5706 Shift-SPC toggle-korean-input-method
5707 C-F9 quail-hangul-switch-symbol-ksc
5708 F9 quail-hangul-switch-hanja
5709 These key bindings are canceled when you switch to another language
5710 environment.
5711
5712 ** The minibuffer history of file names now records the specified file
5713 names, not the entire minibuffer input. For example, if the
5714 minibuffer starts out with /usr/foo/, you might type in /etc/passwd to
5715 get
5716
5717 /usr/foo//etc/passwd
5718
5719 which stands for the file /etc/passwd.
5720
5721 Formerly, this used to put /usr/foo//etc/passwd in the history list.
5722 Now this puts just /etc/passwd in the history list.
5723
5724 ** If you are root, Emacs sets backup-by-copying-when-mismatch to t
5725 at startup, so that saving a file will be sure to preserve
5726 its owner and group.
5727
5728 ** find-func.el can now also find the place of definition of Emacs
5729 Lisp variables in user-loaded libraries.
5730
5731 ** C-x r t (string-rectangle) now deletes the existing rectangle
5732 contents before inserting the specified string on each line.
5733
5734 ** There is a new command delete-whitespace-rectangle
5735 which deletes whitespace starting from a particular column
5736 in all the lines on a rectangle. The column is specified
5737 by the left edge of the rectangle.
5738
5739 ** You can now store a number into a register with C-u NUMBER C-x r n REG,
5740 increment it by INC with C-u INC C-x r + REG (to increment by one, omit
5741 C-u INC), and insert it in the buffer with C-x r g REG. This is useful
5742 for writing keyboard macros.
5743
5744 ** The new command M-x speedbar displays a frame in which directories,
5745 files, and tags can be displayed, manipulated, and jumped to. The
5746 frame defaults to 20 characters in width, and is the same height as
5747 the frame that it was started from. Some major modes define
5748 additional commands for the speedbar, including Rmail, GUD/GDB, and
5749 info.
5750
5751 ** query-replace-regexp is now bound to C-M-%.
5752
5753 ** In Transient Mark mode, when the region is active, M-x
5754 query-replace and the other replace commands now operate on the region
5755 contents only.
5756
5757 ** M-x write-region, when used interactively, now asks for
5758 confirmation before overwriting an existing file. When you call
5759 the function from a Lisp program, a new optional argument CONFIRM
5760 says whether to ask for confirmation in this case.
5761
5762 ** If you use find-file-literally and the file is already visited
5763 non-literally, the command asks you whether to revisit the file
5764 literally. If you say no, it signals an error.
5765
5766 ** Major modes defined with the "derived mode" feature
5767 now use the proper name for the mode hook: WHATEVER-mode-hook.
5768 Formerly they used the name WHATEVER-mode-hooks, but that is
5769 inconsistent with Emacs conventions.
5770
5771 ** shell-command-on-region (and shell-command) reports success or
5772 failure if the command produces no output.
5773
5774 ** Set focus-follows-mouse to nil if your window system or window
5775 manager does not transfer focus to another window when you just move
5776 the mouse.
5777
5778 ** mouse-menu-buffer-maxlen has been renamed to
5779 mouse-buffer-menu-maxlen to be consistent with the other related
5780 function and variable names.
5781
5782 ** The new variable auto-coding-alist specifies coding systems for
5783 reading specific files. This has higher priority than
5784 file-coding-system-alist.
5785
5786 ** If you set the variable unibyte-display-via-language-environment to
5787 t, then Emacs displays non-ASCII characters are displayed by
5788 converting them to the equivalent multibyte characters according to
5789 the current language environment. As a result, they are displayed
5790 according to the current fontset.
5791
5792 ** C-q's handling of codes in the range 0200 through 0377 is changed.
5793
5794 The codes in the range 0200 through 0237 are inserted as one byte of
5795 that code regardless of the values of nonascii-translation-table and
5796 nonascii-insert-offset.
5797
5798 For the codes in the range 0240 through 0377, if
5799 enable-multibyte-characters is non-nil and nonascii-translation-table
5800 nor nonascii-insert-offset can't convert them to valid multibyte
5801 characters, they are converted to Latin-1 characters.
5802
5803 ** If you try to find a file that is not read-accessible, you now get
5804 an error, rather than an empty buffer and a warning.
5805
5806 ** In the minibuffer history commands M-r and M-s, an upper case
5807 letter in the regular expression forces case-sensitive search.
5808
5809 ** In the *Help* buffer, cross-references to commands and variables
5810 are inferred and hyperlinked. Use C-h m in Help mode for the relevant
5811 command keys.
5812
5813 ** M-x apropos-command, with a prefix argument, no longer looks for
5814 user option variables--instead it looks for noninteractive functions.
5815
5816 Meanwhile, the command apropos-variable normally searches for
5817 user option variables; with a prefix argument, it looks at
5818 all variables that have documentation.
5819
5820 ** When you type a long line in the minibuffer, and the minibuffer
5821 shows just one line, automatically scrolling works in a special way
5822 that shows you overlap with the previous line of text. The variable
5823 minibuffer-scroll-overlap controls how many characters of overlap
5824 it should show; the default is 20.
5825
5826 Meanwhile, Resize Minibuffer mode is still available; in that mode,
5827 the minibuffer grows taller (up to a point) as needed to show the whole
5828 of your input.
5829
5830 ** The new command M-x customize-changed-options lets you customize
5831 all the options whose meanings or default values have changed in
5832 recent Emacs versions. You specify a previous Emacs version number as
5833 argument, and the command creates a customization buffer showing all
5834 the customizable options which were changed since that version.
5835 Newly added options are included as well.
5836
5837 If you don't specify a particular version number argument,
5838 then the customization buffer shows all the customizable options
5839 for which Emacs versions of changes are recorded.
5840
5841 This function is also bound to the Changed Options entry in the
5842 Customize menu.
5843
5844 ** When you run M-x grep with a prefix argument, it figures out
5845 the tag around point and puts that into the default grep command.
5846
5847 ** The new command M-* (pop-tag-mark) pops back through a history of
5848 buffer positions from which M-. or other tag-finding commands were
5849 invoked.
5850
5851 ** The new variable comment-padding specifies the number of spaces
5852 that `comment-region' will insert before the actual text of the comment.
5853 The default is 1.
5854
5855 ** In Fortran mode the characters `.', `_' and `$' now have symbol
5856 syntax, not word syntax. Fortran mode now supports `imenu' and has
5857 new commands fortran-join-line (M-^) and fortran-narrow-to-subprogram
5858 (C-x n d). M-q can be used to fill a statement or comment block
5859 sensibly.
5860
5861 ** GUD now supports jdb, the Java debugger, and pdb, the Python debugger.
5862
5863 ** If you set the variable add-log-keep-changes-together to a non-nil
5864 value, the command `C-x 4 a' will automatically notice when you make
5865 two entries in one day for one file, and combine them.
5866
5867 ** You can use the command M-x diary-mail-entries to mail yourself a
5868 reminder about upcoming diary entries. See the documentation string
5869 for a sample shell script for calling this function automatically
5870 every night.
5871
5872 ** Desktop changes
5873
5874 *** All you need to do to enable use of the Desktop package, is to set
5875 the variable desktop-enable to t with Custom.
5876
5877 *** Minor modes are now restored. Which minor modes are restored
5878 and how modes are restored is controlled by `desktop-minor-mode-table'.
5879
5880 ** There is no need to do anything special, now, to enable Gnus to
5881 read and post multi-lingual articles.
5882
5883 ** Outline mode has now support for showing hidden outlines when
5884 doing an isearch. In order for this to happen search-invisible should
5885 be set to open (the default). If an isearch match is inside a hidden
5886 outline the outline is made visible. If you continue pressing C-s and
5887 the match moves outside the formerly invisible outline, the outline is
5888 made invisible again.
5889
5890 ** Mail reading and sending changes
5891
5892 *** The Rmail e command now switches to displaying the whole header of
5893 the message before it lets you edit the message. This is so that any
5894 changes you make in the header will not be lost if you subsequently
5895 toggle.
5896
5897 *** The w command in Rmail, which writes the message body into a file,
5898 now works in the summary buffer as well. (The command to delete the
5899 summary buffer is now Q.) The default file name for the w command, if
5900 the message has no subject, is stored in the variable
5901 rmail-default-body-file.
5902
5903 *** Most of the commands and modes that operate on mail and netnews no
5904 longer depend on the value of mail-header-separator. Instead, they
5905 handle whatever separator the buffer happens to use.
5906
5907 *** If you set mail-signature to a value which is not t, nil, or a string,
5908 it should be an expression. When you send a message, this expression
5909 is evaluated to insert the signature.
5910
5911 *** The new Lisp library feedmail.el (version 8) enhances processing of
5912 outbound email messages. It works in coordination with other email
5913 handling packages (e.g., rmail, VM, gnus) and is responsible for
5914 putting final touches on messages and actually submitting them for
5915 transmission. Users of the emacs program "fakemail" might be
5916 especially interested in trying feedmail.
5917
5918 feedmail is not enabled by default. See comments at the top of
5919 feedmail.el for set-up instructions. Among the bigger features
5920 provided by feedmail are:
5921
5922 **** you can park outgoing messages into a disk-based queue and
5923 stimulate sending some or all of them later (handy for laptop users);
5924 there is also a queue for draft messages
5925
5926 **** you can get one last look at the prepped outbound message and
5927 be prompted for confirmation
5928
5929 **** does smart filling of address headers
5930
5931 **** can generate a MESSAGE-ID: line and a DATE: line; the date can be
5932 the time the message was written or the time it is being sent; this
5933 can make FCC copies more closely resemble copies that recipients get
5934
5935 **** you can specify an arbitrary function for actually transmitting
5936 the message; included in feedmail are interfaces for /bin/[r]mail,
5937 /usr/lib/sendmail, and elisp smtpmail; it's easy to write a new
5938 function for something else (10-20 lines of elisp)
5939
5940 ** Dired changes
5941
5942 *** The Dired function dired-do-toggle, which toggles marked and unmarked
5943 files, is now bound to "t" instead of "T".
5944
5945 *** dired-at-point has been added to ffap.el. It allows one to easily
5946 run Dired on the directory name at point.
5947
5948 *** Dired has a new command: %g. It searches the contents of
5949 files in the directory and marks each file that contains a match
5950 for a specified regexp.
5951
5952 ** VC Changes
5953
5954 *** New option vc-ignore-vc-files lets you turn off version control
5955 conveniently.
5956
5957 *** VC Dired has been completely rewritten. It is now much
5958 faster, especially for CVS, and works very similar to ordinary
5959 Dired.
5960
5961 VC Dired is invoked by typing C-x v d and entering the name of the
5962 directory to display. By default, VC Dired gives you a recursive
5963 listing of all files at or below the given directory which are
5964 currently locked (for CVS, all files not up-to-date are shown).
5965
5966 You can change the listing format by setting vc-dired-recurse to nil,
5967 then it shows only the given directory, and you may also set
5968 vc-dired-terse-display to nil, then it shows all files under version
5969 control plus the names of any subdirectories, so that you can type `i'
5970 on such lines to insert them manually, as in ordinary Dired.
5971
5972 All Dired commands operate normally in VC Dired, except for `v', which
5973 is redefined as the version control prefix. That means you may type
5974 `v l', `v =' etc. to invoke `vc-print-log', `vc-diff' and the like on
5975 the file named in the current Dired buffer line. `v v' invokes
5976 `vc-next-action' on this file, or on all files currently marked.
5977
5978 The new command `v t' (vc-dired-toggle-terse-mode) allows you to
5979 toggle between terse display (only locked files) and full display (all
5980 VC files plus subdirectories). There is also a special command,
5981 `* l', to mark all files currently locked.
5982
5983 Giving a prefix argument to C-x v d now does the same thing as in
5984 ordinary Dired: it allows you to supply additional options for the ls
5985 command in the minibuffer, to fine-tune VC Dired's output.
5986
5987 *** Under CVS, if you merge changes from the repository into a working
5988 file, and CVS detects conflicts, VC now offers to start an ediff
5989 session to resolve them.
5990
5991 Alternatively, you can use the new command `vc-resolve-conflicts' to
5992 resolve conflicts in a file at any time. It works in any buffer that
5993 contains conflict markers as generated by rcsmerge (which is what CVS
5994 uses as well).
5995
5996 *** You can now transfer changes between branches, using the new
5997 command vc-merge (C-x v m). It is implemented for RCS and CVS. When
5998 you invoke it in a buffer under version-control, you can specify
5999 either an entire branch or a pair of versions, and the changes on that
6000 branch or between the two versions are merged into the working file.
6001 If this results in any conflicts, they may be resolved interactively,
6002 using ediff.
6003
6004 ** Changes in Font Lock
6005
6006 *** The face and variable previously known as font-lock-reference-face
6007 are now called font-lock-constant-face to better reflect their typical
6008 use for highlighting constants and labels. (Its face properties are
6009 unchanged.) The variable font-lock-reference-face remains for now for
6010 compatibility reasons, but its value is font-lock-constant-face.
6011
6012 ** Frame name display changes
6013
6014 *** The command set-frame-name lets you set the name of the current
6015 frame. You can use the new command select-frame-by-name to select and
6016 raise a frame; this is mostly useful on character-only terminals, or
6017 when many frames are invisible or iconified.
6018
6019 *** On character-only terminal (not a window system), changing the
6020 frame name is now reflected on the mode line and in the Buffers/Frames
6021 menu.
6022
6023 ** Comint (subshell) changes
6024
6025 *** In Comint modes, the commands to kill, stop or interrupt a
6026 subjob now also kill pending input. This is for compatibility
6027 with ordinary shells, where the signal characters do this.
6028
6029 *** There are new commands in Comint mode.
6030
6031 C-c C-x fetches the "next" line from the input history;
6032 that is, the line after the last line you got.
6033 You can use this command to fetch successive lines, one by one.
6034
6035 C-c SPC accumulates lines of input. More precisely, it arranges to
6036 send the current line together with the following line, when you send
6037 the following line.
6038
6039 C-c C-a if repeated twice consecutively now moves to the process mark,
6040 which separates the pending input from the subprocess output and the
6041 previously sent input.
6042
6043 C-c M-r now runs comint-previous-matching-input-from-input;
6044 it searches for a previous command, using the current pending input
6045 as the search string.
6046
6047 *** New option compilation-scroll-output can be set to scroll
6048 automatically in compilation-mode windows.
6049
6050 ** C mode changes
6051
6052 *** Multiline macros are now handled, both as they affect indentation,
6053 and as recognized syntax. New syntactic symbol cpp-macro-cont is
6054 assigned to second and subsequent lines of a multiline macro
6055 definition.
6056
6057 *** A new style "user" which captures all non-hook-ified
6058 (i.e. top-level) .emacs file variable settings and customizations.
6059 Style "cc-mode" is an alias for "user" and is deprecated. "gnu"
6060 style is still the default however.
6061
6062 *** "java" style now conforms to Sun's JDK coding style.
6063
6064 *** There are new commands c-beginning-of-defun, c-end-of-defun which
6065 are alternatives which you could bind to C-M-a and C-M-e if you prefer
6066 them. They do not have key bindings by default.
6067
6068 *** New and improved implementations of M-a (c-beginning-of-statement)
6069 and M-e (c-end-of-statement).
6070
6071 *** C++ namespace blocks are supported, with new syntactic symbols
6072 namespace-open, namespace-close, and innamespace.
6073
6074 *** File local variable settings of c-file-style and c-file-offsets
6075 makes the style variables local to that buffer only.
6076
6077 *** New indentation functions c-lineup-close-paren,
6078 c-indent-one-line-block, c-lineup-dont-change.
6079
6080 *** Improvements (hopefully!) to the way CC Mode is loaded. You
6081 should now be able to do a (require 'cc-mode) to get the entire
6082 package loaded properly for customization in your .emacs file. A new
6083 variable c-initialize-on-load controls this and is t by default.
6084
6085 ** Changes to hippie-expand.
6086
6087 *** New customization variable `hippie-expand-dabbrev-skip-space'. If
6088 non-nil, trailing spaces may be included in the abbreviation to search for,
6089 which then gives the same behavior as the original `dabbrev-expand'.
6090
6091 *** New customization variable `hippie-expand-dabbrev-as-symbol'. If
6092 non-nil, characters of syntax '_' is considered part of the word when
6093 expanding dynamically.
6094
6095 *** New customization variable `hippie-expand-no-restriction'. If
6096 non-nil, narrowed buffers are widened before they are searched.
6097
6098 *** New customization variable `hippie-expand-only-buffers'. If
6099 non-empty, buffers searched are restricted to the types specified in
6100 this list. Useful for example when constructing new special-purpose
6101 expansion functions with `make-hippie-expand-function'.
6102
6103 *** Text properties of the expansion are no longer copied.
6104
6105 ** Changes in BibTeX mode.
6106
6107 *** Any titleword matching a regexp in the new variable
6108 bibtex-autokey-titleword-ignore (case sensitive) is ignored during
6109 automatic key generation. This replaces variable
6110 bibtex-autokey-titleword-first-ignore, which only checked for matches
6111 against the first word in the title.
6112
6113 *** Autokey generation now uses all words from the title, not just
6114 capitalized words. To avoid conflicts with existing customizations,
6115 bibtex-autokey-titleword-ignore is set up such that words starting with
6116 lowerkey characters will still be ignored. Thus, if you want to use
6117 lowercase words from the title, you will have to overwrite the
6118 bibtex-autokey-titleword-ignore standard setting.
6119
6120 *** Case conversion of names and title words for automatic key
6121 generation is more flexible. Variable bibtex-autokey-preserve-case is
6122 replaced by bibtex-autokey-titleword-case-convert and
6123 bibtex-autokey-name-case-convert.
6124
6125 ** Changes in vcursor.el.
6126
6127 *** Support for character terminals is available: there is a new keymap
6128 and the vcursor will appear as an arrow between buffer text. A
6129 variable `vcursor-interpret-input' allows input from the vcursor to be
6130 entered exactly as if typed. Numerous functions, including
6131 `vcursor-compare-windows', have been rewritten to improve consistency
6132 in the selection of windows and corresponding keymaps.
6133
6134 *** vcursor options can now be altered with M-x customize under the
6135 Editing group once the package is loaded.
6136
6137 *** Loading vcursor now does not define keys by default, as this is
6138 generally a bad side effect. Use M-x customize to set
6139 vcursor-key-bindings to t to restore the old behavior.
6140
6141 *** vcursor-auto-disable can be `copy', which turns off copying from the
6142 vcursor, but doesn't disable it, after any non-vcursor command.
6143
6144 ** Ispell changes.
6145
6146 *** You can now spell check comments and strings in the current
6147 buffer with M-x ispell-comments-and-strings. Comments and strings
6148 are identified by syntax tables in effect.
6149
6150 *** Generic region skipping implemented.
6151 A single buffer can be broken into a number of regions where text will
6152 and will not be checked. The definitions of the regions can be user
6153 defined. New applications and improvements made available by this
6154 include:
6155
6156 o URLs are automatically skipped
6157 o EMail message checking is vastly improved.
6158
6159 *** Ispell can highlight the erroneous word even on non-window terminals.
6160
6161 ** Changes to RefTeX mode
6162
6163 RefTeX has been updated in order to make it more usable with very
6164 large projects (like a several volume math book). The parser has been
6165 re-written from scratch. To get maximum speed from RefTeX, check the
6166 section `Optimizations' in the manual.
6167
6168 *** New recursive parser.
6169
6170 The old version of RefTeX created a single large buffer containing the
6171 entire multifile document in order to parse the document. The new
6172 recursive parser scans the individual files.
6173
6174 *** Parsing only part of a document.
6175
6176 Reparsing of changed document parts can now be made faster by enabling
6177 partial scans. To use this feature, read the documentation string of
6178 the variable `reftex-enable-partial-scans' and set the variable to t.
6179
6180 (setq reftex-enable-partial-scans t)
6181
6182 *** Storing parsing information in a file.
6183
6184 This can improve startup times considerably. To turn it on, use
6185
6186 (setq reftex-save-parse-info t)
6187
6188 *** Using multiple selection buffers
6189
6190 If the creation of label selection buffers is too slow (this happens
6191 for large documents), you can reuse these buffers by setting
6192
6193 (setq reftex-use-multiple-selection-buffers t)
6194
6195 *** References to external documents.
6196
6197 The LaTeX package `xr' allows to cross-reference labels in external
6198 documents. RefTeX can provide information about the external
6199 documents as well. To use this feature, set up the \externaldocument
6200 macros required by the `xr' package and rescan the document with
6201 RefTeX. The external labels can then be accessed with the `x' key in
6202 the selection buffer provided by `reftex-reference' (bound to `C-c )').
6203 The `x' key also works in the table of contents buffer.
6204
6205 *** Many more labeled LaTeX environments are recognized by default.
6206
6207 The built-in command list now covers all the standard LaTeX commands,
6208 and all of the major packages included in the LaTeX distribution.
6209
6210 Also, RefTeX now understands the \appendix macro and changes
6211 the enumeration of sections in the *toc* buffer accordingly.
6212
6213 *** Mouse support for selection and *toc* buffers
6214
6215 The mouse can now be used to select items in the selection and *toc*
6216 buffers. See also the new option `reftex-highlight-selection'.
6217
6218 *** New keymaps for selection and table of contents modes.
6219
6220 The selection processes for labels and citation keys, and the table of
6221 contents buffer now have their own keymaps: `reftex-select-label-map',
6222 `reftex-select-bib-map', `reftex-toc-map'. The selection processes
6223 have a number of new keys predefined. In particular, TAB lets you
6224 enter a label with completion. Check the on-the-fly help (press `?'
6225 at the selection prompt) or read the Info documentation to find out
6226 more.
6227
6228 *** Support for the varioref package
6229
6230 The `v' key in the label selection buffer toggles \ref versus \vref.
6231
6232 *** New hooks
6233
6234 Three new hooks can be used to redefine the way labels, references,
6235 and citations are created. These hooks are
6236 `reftex-format-label-function', `reftex-format-ref-function',
6237 `reftex-format-cite-function'.
6238
6239 *** Citations outside LaTeX
6240
6241 The command `reftex-citation' may also be used outside LaTeX (e.g. in
6242 a mail buffer). See the Info documentation for details.
6243
6244 *** Short context is no longer fontified.
6245
6246 The short context in the label menu no longer copies the
6247 fontification from the text in the buffer. If you prefer it to be
6248 fontified, use
6249
6250 (setq reftex-refontify-context t)
6251
6252 ** file-cache-minibuffer-complete now accepts a prefix argument.
6253 With a prefix argument, it does not try to do completion of
6254 the file name within its directory; it only checks for other
6255 directories that contain the same file name.
6256
6257 Thus, given the file name Makefile, and assuming that a file
6258 Makefile.in exists in the same directory, ordinary
6259 file-cache-minibuffer-complete will try to complete Makefile to
6260 Makefile.in and will therefore never look for other directories that
6261 have Makefile. A prefix argument tells it not to look for longer
6262 names such as Makefile.in, so that instead it will look for other
6263 directories--just as if the name were already complete in its present
6264 directory.
6265
6266 ** New modes and packages
6267
6268 *** There is a new alternative major mode for Perl, Cperl mode.
6269 It has many more features than Perl mode, and some people prefer
6270 it, but some do not.
6271
6272 *** There is a new major mode, M-x vhdl-mode, for editing files of VHDL
6273 code.
6274
6275 *** M-x which-function-mode enables a minor mode that displays the
6276 current function name continuously in the mode line, as you move
6277 around in a buffer.
6278
6279 Which Function mode is effective in major modes which support Imenu.
6280
6281 *** Gametree is a major mode for editing game analysis trees. The author
6282 uses it for keeping notes about his postal Chess games, but it should
6283 be helpful for other two-player games as well, as long as they have an
6284 established system of notation similar to Chess.
6285
6286 *** The new minor mode checkdoc-minor-mode provides Emacs Lisp
6287 documentation string checking for style and spelling. The style
6288 guidelines are found in the Emacs Lisp programming manual.
6289
6290 *** The net-utils package makes some common networking features
6291 available in Emacs. Some of these functions are wrappers around
6292 system utilities (ping, nslookup, etc); others are implementations of
6293 simple protocols (finger, whois) in Emacs Lisp. There are also
6294 functions to make simple connections to TCP/IP ports for debugging and
6295 the like.
6296
6297 *** highlight-changes-mode is a minor mode that uses colors to
6298 identify recently changed parts of the buffer text.
6299
6300 *** The new package `midnight' lets you specify things to be done
6301 within Emacs at midnight--by default, kill buffers that you have not
6302 used in a considerable time. To use this feature, customize
6303 the user option `midnight-mode' to t.
6304
6305 *** The file generic-x.el defines a number of simple major modes.
6306
6307 apache-generic-mode: For Apache and NCSA httpd configuration files
6308 samba-generic-mode: Samba configuration files
6309 fvwm-generic-mode: For fvwm initialization files
6310 x-resource-generic-mode: For X resource files
6311 hosts-generic-mode: For hosts files (.rhosts, /etc/hosts, etc)
6312 mailagent-rules-generic-mode: For mailagent .rules files
6313 javascript-generic-mode: For JavaScript files
6314 vrml-generic-mode: For VRML files
6315 java-manifest-generic-mode: For Java MANIFEST files
6316 java-properties-generic-mode: For Java property files
6317 mailrc-generic-mode: For .mailrc files
6318
6319 Platform-specific modes:
6320
6321 prototype-generic-mode: For Solaris/Sys V prototype files
6322 pkginfo-generic-mode: For Solaris/Sys V pkginfo files
6323 alias-generic-mode: For C shell alias files
6324 inf-generic-mode: For MS-Windows INF files
6325 ini-generic-mode: For MS-Windows INI files
6326 reg-generic-mode: For MS-Windows Registry files
6327 bat-generic-mode: For MS-Windows BAT scripts
6328 rc-generic-mode: For MS-Windows Resource files
6329 rul-generic-mode: For InstallShield scripts
6330 \f
6331 * Lisp changes in Emacs 20.3 since the Emacs Lisp Manual was published
6332
6333 ** If you want a Lisp file to be read in unibyte mode,
6334 use -*-unibyte: t;-*- on its first line.
6335 That will force Emacs to read that file in unibyte mode.
6336 Otherwise, the file will be loaded and byte-compiled in multibyte mode.
6337
6338 Thus, each lisp file is read in a consistent way regardless of whether
6339 you started Emacs with --unibyte, so that a Lisp program gives
6340 consistent results regardless of how Emacs was started.
6341
6342 ** The new function assoc-default is useful for searching an alist,
6343 and using a default value if the key is not found there. You can
6344 specify a comparison predicate, so this function is useful for
6345 searching comparing a string against an alist of regular expressions.
6346
6347 ** The functions unibyte-char-to-multibyte and
6348 multibyte-char-to-unibyte convert between unibyte and multibyte
6349 character codes, in a way that is appropriate for the current language
6350 environment.
6351
6352 ** The functions read-event, read-char and read-char-exclusive now
6353 take two optional arguments. PROMPT, if non-nil, specifies a prompt
6354 string. SUPPRESS-INPUT-METHOD, if non-nil, says to disable the
6355 current input method for reading this one event.
6356
6357 ** Two new variables print-escape-nonascii and print-escape-multibyte
6358 now control whether to output certain characters as
6359 backslash-sequences. print-escape-nonascii applies to single-byte
6360 non-ASCII characters; print-escape-multibyte applies to multibyte
6361 characters. Both of these variables are used only when printing
6362 in readable fashion (prin1 uses them, princ does not).
6363 \f
6364 * Lisp changes in Emacs 20.3 before the Emacs Lisp Manual was published
6365
6366 ** Compiled Emacs Lisp files made with the modified "MBSK" version
6367 of Emacs 20.2 do not work in Emacs 20.3.
6368
6369 ** Buffer positions are now measured in characters, as they were
6370 in Emacs 19 and before. This means that (forward-char 1)
6371 always increases point by 1.
6372
6373 The function chars-in-region now just subtracts its arguments. It is
6374 considered obsolete. The function char-boundary-p has been deleted.
6375
6376 See below for additional changes relating to multibyte characters.
6377
6378 ** defcustom, defface and defgroup now accept the keyword `:version'.
6379 Use this to specify in which version of Emacs a certain variable's
6380 default value changed. For example,
6381
6382 (defcustom foo-max 34 "*Maximum number of foo's allowed."
6383 :type 'integer
6384 :group 'foo
6385 :version "20.3")
6386
6387 (defgroup foo-group nil "The foo group."
6388 :version "20.3")
6389
6390 If an entire new group is added or the variables in it have the
6391 default values changed, then just add a `:version' to that group. It
6392 is recommended that new packages added to the distribution contain a
6393 `:version' in the top level group.
6394
6395 This information is used to control the customize-changed-options command.
6396
6397 ** It is now an error to change the value of a symbol whose name
6398 starts with a colon--if it is interned in the standard obarray.
6399
6400 However, setting such a symbol to its proper value, which is that
6401 symbol itself, is not an error. This is for the sake of programs that
6402 support previous Emacs versions by explicitly setting these variables
6403 to themselves.
6404
6405 If you set the variable keyword-symbols-constant-flag to nil,
6406 this error is suppressed, and you can set these symbols to any
6407 values whatever.
6408
6409 ** There is a new debugger command, R.
6410 It evaluates an expression like e, but saves the result
6411 in the buffer *Debugger-record*.
6412
6413 ** Frame-local variables.
6414
6415 You can now make a variable local to various frames. To do this, call
6416 the function make-variable-frame-local; this enables frames to have
6417 local bindings for that variable.
6418
6419 These frame-local bindings are actually frame parameters: you create a
6420 frame-local binding in a specific frame by calling
6421 modify-frame-parameters and specifying the variable name as the
6422 parameter name.
6423
6424 Buffer-local bindings take precedence over frame-local bindings.
6425 Thus, if the current buffer has a buffer-local binding, that binding is
6426 active; otherwise, if the selected frame has a frame-local binding,
6427 that binding is active; otherwise, the default binding is active.
6428
6429 It would not be hard to implement window-local bindings, but it is not
6430 clear that this would be very useful; windows tend to come and go in a
6431 very transitory fashion, so that trying to produce any specific effect
6432 through a window-local binding would not be very robust.
6433
6434 ** `sregexq' and `sregex' are two new functions for constructing
6435 "symbolic regular expressions." These are Lisp expressions that, when
6436 evaluated, yield conventional string-based regexps. The symbolic form
6437 makes it easier to construct, read, and maintain complex patterns.
6438 See the documentation in sregex.el.
6439
6440 ** parse-partial-sexp's return value has an additional element which
6441 is used to pass information along if you pass it to another call to
6442 parse-partial-sexp, starting its scan where the first call ended.
6443 The contents of this field are not yet finalized.
6444
6445 ** eval-region now accepts a fourth optional argument READ-FUNCTION.
6446 If it is non-nil, that function is used instead of `read'.
6447
6448 ** unload-feature by default removes the feature's functions from
6449 known hooks to avoid trouble, but a package providing FEATURE can
6450 define a hook FEATURE-unload-hook to be run by unload-feature instead.
6451
6452 ** read-from-minibuffer no longer returns the argument DEFAULT-VALUE
6453 when the user enters empty input. It now returns the null string, as
6454 it did in Emacs 19. The default value is made available in the
6455 history via M-n, but it is not applied here as a default.
6456
6457 The other, more specialized minibuffer-reading functions continue to
6458 return the default value (not the null string) when the user enters
6459 empty input.
6460
6461 ** The new variable read-buffer-function controls which routine to use
6462 for selecting buffers. For example, if you set this variable to
6463 `iswitchb-read-buffer', iswitchb will be used to read buffer names.
6464 Other functions can also be used if they accept the same arguments as
6465 `read-buffer' and return the selected buffer name as a string.
6466
6467 ** The new function read-passwd reads a password from the terminal,
6468 echoing a period for each character typed. It takes three arguments:
6469 a prompt string, a flag which says "read it twice to make sure", and a
6470 default password to use if the user enters nothing.
6471
6472 ** The variable fill-nobreak-predicate gives major modes a way to
6473 specify not to break a line at certain places. Its value is a
6474 function which is called with no arguments, with point located at the
6475 place where a break is being considered. If the function returns
6476 non-nil, then the line won't be broken there.
6477
6478 ** window-end now takes an optional second argument, UPDATE.
6479 If this is non-nil, then the function always returns an accurate
6480 up-to-date value for the buffer position corresponding to the
6481 end of the window, even if this requires computation.
6482
6483 ** other-buffer now takes an optional argument FRAME
6484 which specifies which frame's buffer list to use.
6485 If it is nil, that means use the selected frame's buffer list.
6486
6487 ** The new variable buffer-display-time, always local in every buffer,
6488 holds the value of (current-time) as of the last time that a window
6489 was directed to display this buffer.
6490
6491 ** It is now meaningful to compare two window-configuration objects
6492 with `equal'. Two window-configuration objects are equal if they
6493 describe equivalent arrangements of windows, in the same frame--in
6494 other words, if they would give the same results if passed to
6495 set-window-configuration.
6496
6497 ** compare-window-configurations is a new function that compares two
6498 window configurations loosely. It ignores differences in saved buffer
6499 positions and scrolling, and considers only the structure and sizes of
6500 windows and the choice of buffers to display.
6501
6502 ** The variable minor-mode-overriding-map-alist allows major modes to
6503 override the key bindings of a minor mode. The elements of this alist
6504 look like the elements of minor-mode-map-alist: (VARIABLE . KEYMAP).
6505
6506 If the VARIABLE in an element of minor-mode-overriding-map-alist has a
6507 non-nil value, the paired KEYMAP is active, and totally overrides the
6508 map (if any) specified for the same variable in minor-mode-map-alist.
6509
6510 minor-mode-overriding-map-alist is automatically local in all buffers,
6511 and it is meant to be set by major modes.
6512
6513 ** The function match-string-no-properties is like match-string
6514 except that it discards all text properties from the result.
6515
6516 ** The function load-average now accepts an optional argument
6517 USE-FLOATS. If it is non-nil, the load average values are returned as
6518 floating point numbers, rather than as integers to be divided by 100.
6519
6520 ** The new variable temporary-file-directory specifies the directory
6521 to use for creating temporary files. The default value is determined
6522 in a reasonable way for your operating system; on GNU and Unix systems
6523 it is based on the TMP and TMPDIR environment variables.
6524
6525 ** Menu changes
6526
6527 *** easymenu.el now uses the new menu item format and supports the
6528 keywords :visible and :filter. The existing keyword :keys is now
6529 better supported.
6530
6531 The variable `easy-menu-precalculate-equivalent-keybindings' controls
6532 a new feature which calculates keyboard equivalents for the menu when
6533 you define the menu. The default is t. If you rarely use menus, you
6534 can set the variable to nil to disable this precalculation feature;
6535 then the calculation is done only if you use the menu bar.
6536
6537 *** A new format for menu items is supported.
6538
6539 In a keymap, a key binding that has the format
6540 (STRING . REAL-BINDING) or (STRING HELP-STRING . REAL-BINDING)
6541 defines a menu item. Now a menu item definition may also be a list that
6542 starts with the symbol `menu-item'.
6543
6544 The format is:
6545 (menu-item ITEM-NAME) or
6546 (menu-item ITEM-NAME REAL-BINDING . ITEM-PROPERTY-LIST)
6547 where ITEM-NAME is an expression which evaluates to the menu item
6548 string, and ITEM-PROPERTY-LIST has the form of a property list.
6549 The supported properties include
6550
6551 :enable FORM Evaluate FORM to determine whether the
6552 item is enabled.
6553 :visible FORM Evaluate FORM to determine whether the
6554 item should appear in the menu.
6555 :filter FILTER-FN
6556 FILTER-FN is a function of one argument,
6557 which will be REAL-BINDING.
6558 It should return a binding to use instead.
6559 :keys DESCRIPTION
6560 DESCRIPTION is a string that describes an equivalent keyboard
6561 binding for REAL-BINDING. DESCRIPTION is expanded with
6562 `substitute-command-keys' before it is used.
6563 :key-sequence KEY-SEQUENCE
6564 KEY-SEQUENCE is a key-sequence for an equivalent
6565 keyboard binding.
6566 :key-sequence nil
6567 This means that the command normally has no
6568 keyboard equivalent.
6569 :help HELP HELP is the extra help string (not currently used).
6570 :button (TYPE . SELECTED)
6571 TYPE is :toggle or :radio.
6572 SELECTED is a form, to be evaluated, and its
6573 value says whether this button is currently selected.
6574
6575 Buttons are at the moment only simulated by prefixes in the menu.
6576 Eventually ordinary X-buttons may be supported.
6577
6578 (menu-item ITEM-NAME) defines unselectable item.
6579
6580 ** New event types
6581
6582 *** The new event type `mouse-wheel' is generated by a wheel on a
6583 mouse (such as the MS Intellimouse). The event contains a delta that
6584 corresponds to the amount and direction that the wheel is rotated,
6585 which is typically used to implement a scroll or zoom. The format is:
6586
6587 (mouse-wheel POSITION DELTA)
6588
6589 where POSITION is a list describing the position of the event in the
6590 same format as a mouse-click event, and DELTA is a signed number
6591 indicating the number of increments by which the wheel was rotated. A
6592 negative DELTA indicates that the wheel was rotated backwards, towards
6593 the user, and a positive DELTA indicates that the wheel was rotated
6594 forward, away from the user.
6595
6596 As of now, this event type is generated only on MS Windows.
6597
6598 *** The new event type `drag-n-drop' is generated when a group of
6599 files is selected in an application outside of Emacs, and then dragged
6600 and dropped onto an Emacs frame. The event contains a list of
6601 filenames that were dragged and dropped, which are then typically
6602 loaded into Emacs. The format is:
6603
6604 (drag-n-drop POSITION FILES)
6605
6606 where POSITION is a list describing the position of the event in the
6607 same format as a mouse-click event, and FILES is the list of filenames
6608 that were dragged and dropped.
6609
6610 As of now, this event type is generated only on MS Windows.
6611
6612 ** Changes relating to multibyte characters.
6613
6614 *** The variable enable-multibyte-characters is now read-only;
6615 any attempt to set it directly signals an error. The only way
6616 to change this value in an existing buffer is with set-buffer-multibyte.
6617
6618 *** In a string constant, `\ ' now stands for "nothing at all". You
6619 can use it to terminate a hex escape which is followed by a character
6620 that could otherwise be read as part of the hex escape.
6621
6622 *** String indices are now measured in characters, as they were
6623 in Emacs 19 and before.
6624
6625 The function chars-in-string has been deleted.
6626 The function concat-chars has been renamed to `string'.
6627
6628 *** The function set-buffer-multibyte sets the flag in the current
6629 buffer that says whether the buffer uses multibyte representation or
6630 unibyte representation. If the argument is nil, it selects unibyte
6631 representation. Otherwise it selects multibyte representation.
6632
6633 This function does not change the contents of the buffer, viewed
6634 as a sequence of bytes. However, it does change the contents
6635 viewed as characters; a sequence of two bytes which is treated as
6636 one character when the buffer uses multibyte representation
6637 will count as two characters using unibyte representation.
6638
6639 This function sets enable-multibyte-characters to record which
6640 representation is in use. It also adjusts various data in the buffer
6641 (including its markers, overlays and text properties) so that they are
6642 consistent with the new representation.
6643
6644 *** string-make-multibyte takes a string and converts it to multibyte
6645 representation. Most of the time, you don't need to care
6646 about the representation, because Emacs converts when necessary;
6647 however, it makes a difference when you compare strings.
6648
6649 The conversion of non-ASCII characters works by adding the value of
6650 nonascii-insert-offset to each character, or by translating them
6651 using the table nonascii-translation-table.
6652
6653 *** string-make-unibyte takes a string and converts it to unibyte
6654 representation. Most of the time, you don't need to care about the
6655 representation, but it makes a difference when you compare strings.
6656
6657 The conversion from multibyte to unibyte representation
6658 loses information; the only time Emacs performs it automatically
6659 is when inserting a multibyte string into a unibyte buffer.
6660
6661 *** string-as-multibyte takes a string, and returns another string
6662 which contains the same bytes, but treats them as multibyte.
6663
6664 *** string-as-unibyte takes a string, and returns another string
6665 which contains the same bytes, but treats them as unibyte.
6666
6667 *** The new function compare-strings lets you compare
6668 portions of two strings. Unibyte strings are converted to multibyte,
6669 so that a unibyte string can match a multibyte string.
6670 You can specify whether to ignore case or not.
6671
6672 *** assoc-ignore-case now uses compare-strings so that
6673 it can treat unibyte and multibyte strings as equal.
6674
6675 *** Regular expression operations and buffer string searches now
6676 convert the search pattern to multibyte or unibyte to accord with the
6677 buffer or string being searched.
6678
6679 One consequence is that you cannot always use \200-\377 inside of
6680 [...] to match all non-ASCII characters. This does still work when
6681 searching or matching a unibyte buffer or string, but not when
6682 searching or matching a multibyte string. Unfortunately, there is no
6683 obvious choice of syntax to use within [...] for that job. But, what
6684 you want is just to match all non-ASCII characters, the regular
6685 expression [^\0-\177] works for it.
6686
6687 *** Structure of coding system changed.
6688
6689 All coding systems (including aliases and subsidiaries) are named
6690 by symbols; the symbol's `coding-system' property is a vector
6691 which defines the coding system. Aliases share the same vector
6692 as the principal name, so that altering the contents of this
6693 vector affects the principal name and its aliases. You can define
6694 your own alias name of a coding system by the function
6695 define-coding-system-alias.
6696
6697 The coding system definition includes a property list of its own. Use
6698 the new functions `coding-system-get' and `coding-system-put' to
6699 access such coding system properties as post-read-conversion,
6700 pre-write-conversion, character-translation-table-for-decode,
6701 character-translation-table-for-encode, mime-charset, and
6702 safe-charsets. For instance, (coding-system-get 'iso-latin-1
6703 'mime-charset) gives the corresponding MIME-charset parameter
6704 `iso-8859-1'.
6705
6706 Among the coding system properties listed above, safe-charsets is new.
6707 The value of this property is a list of character sets which this
6708 coding system can correctly encode and decode. For instance:
6709 (coding-system-get 'iso-latin-1 'safe-charsets) => (ascii latin-iso8859-1)
6710
6711 Here, "correctly encode" means that the encoded character sets can
6712 also be handled safely by systems other than Emacs as far as they
6713 are capable of that coding system. Though, Emacs itself can encode
6714 the other character sets and read it back correctly.
6715
6716 *** The new function select-safe-coding-system can be used to find a
6717 proper coding system for encoding the specified region or string.
6718 This function requires a user interaction.
6719
6720 *** The new functions find-coding-systems-region and
6721 find-coding-systems-string are helper functions used by
6722 select-safe-coding-system. They return a list of all proper coding
6723 systems to encode a text in some region or string. If you don't want
6724 a user interaction, use one of these functions instead of
6725 select-safe-coding-system.
6726
6727 *** The explicit encoding and decoding functions, such as
6728 decode-coding-region and encode-coding-string, now set
6729 last-coding-system-used to reflect the actual way encoding or decoding
6730 was done.
6731
6732 *** The new function detect-coding-with-language-environment can be
6733 used to detect a coding system of text according to priorities of
6734 coding systems used by some specific language environment.
6735
6736 *** The functions detect-coding-region and detect-coding-string always
6737 return a list if the arg HIGHEST is nil. Thus, if only ASCII
6738 characters are found, they now return a list of single element
6739 `undecided' or its subsidiaries.
6740
6741 *** The new functions coding-system-change-eol-conversion and
6742 coding-system-change-text-conversion can be used to get a different
6743 coding system than what specified only in how end-of-line or text is
6744 converted.
6745
6746 *** The new function set-selection-coding-system can be used to set a
6747 coding system for communicating with other X clients.
6748
6749 *** The function `map-char-table' now passes as argument only valid
6750 character codes, plus generic characters that stand for entire
6751 character sets or entire subrows of a character set. In other words,
6752 each time `map-char-table' calls its FUNCTION argument, the key value
6753 either will be a valid individual character code, or will stand for a
6754 range of characters.
6755
6756 *** The new function `char-valid-p' can be used for checking whether a
6757 Lisp object is a valid character code or not.
6758
6759 *** The new function `charset-after' returns a charset of a character
6760 in the current buffer at position POS.
6761
6762 *** Input methods are now implemented using the variable
6763 input-method-function. If this is non-nil, its value should be a
6764 function; then, whenever Emacs reads an input event that is a printing
6765 character with no modifier bits, it calls that function, passing the
6766 event as an argument. Often this function will read more input, first
6767 binding input-method-function to nil.
6768
6769 The return value should be a list of the events resulting from input
6770 method processing. These events will be processed sequentially as
6771 input, before resorting to unread-command-events. Events returned by
6772 the input method function are not passed to the input method function,
6773 not even if they are printing characters with no modifier bits.
6774
6775 The input method function is not called when reading the second and
6776 subsequent events of a key sequence.
6777
6778 *** You can customize any language environment by using
6779 set-language-environment-hook and exit-language-environment-hook.
6780
6781 The hook `exit-language-environment-hook' should be used to undo
6782 customizations that you made with set-language-environment-hook. For
6783 instance, if you set up a special key binding for a specific language
6784 environment by set-language-environment-hook, you should set up
6785 exit-language-environment-hook to restore the normal key binding.
6786 \f
6787 * Changes in Emacs 20.1
6788
6789 ** Emacs has a new facility for customization of its many user
6790 options. It is called M-x customize. With this facility you can look
6791 at the many user options in an organized way; they are grouped into a
6792 tree structure.
6793
6794 M-x customize also knows what sorts of values are legitimate for each
6795 user option and ensures that you don't use invalid values.
6796
6797 With M-x customize, you can set options either for the present Emacs
6798 session or permanently. (Permanent settings are stored automatically
6799 in your .emacs file.)
6800
6801 ** Scroll bars are now on the left side of the window.
6802 You can change this with M-x customize-option scroll-bar-mode.
6803
6804 ** The mode line no longer includes the string `Emacs'.
6805 This makes more space in the mode line for other information.
6806
6807 ** When you select a region with the mouse, it is highlighted
6808 immediately afterward. At that time, if you type the DELETE key, it
6809 kills the region.
6810
6811 The BACKSPACE key, and the ASCII character DEL, do not do this; they
6812 delete the character before point, as usual.
6813
6814 ** In an incremental search the whole current match is highlighted
6815 on terminals which support this. (You can disable this feature
6816 by setting search-highlight to nil.)
6817
6818 ** In the minibuffer, in some cases, you can now use M-n to
6819 insert the default value into the minibuffer as text. In effect,
6820 the default value (if the minibuffer routines know it) is tacked
6821 onto the history "in the future". (The more normal use of the
6822 history list is to use M-p to insert minibuffer input used in the
6823 past.)
6824
6825 ** In Text mode, now only blank lines separate paragraphs.
6826 This makes it possible to get the full benefit of Adaptive Fill mode
6827 in Text mode, and other modes derived from it (such as Mail mode).
6828 TAB in Text mode now runs the command indent-relative; this
6829 makes a practical difference only when you use indented paragraphs.
6830
6831 As a result, the old Indented Text mode is now identical to Text mode,
6832 and is an alias for it.
6833
6834 If you want spaces at the beginning of a line to start a paragraph,
6835 use the new mode, Paragraph Indent Text mode.
6836
6837 ** Scrolling changes
6838
6839 *** Scroll commands to scroll a whole screen now preserve the screen
6840 position of the cursor, if scroll-preserve-screen-position is non-nil.
6841
6842 In this mode, if you scroll several screens back and forth, finishing
6843 on the same screen where you started, the cursor goes back to the line
6844 where it started.
6845
6846 *** If you set scroll-conservatively to a small number, then when you
6847 move point a short distance off the screen, Emacs will scroll the
6848 screen just far enough to bring point back on screen, provided that
6849 does not exceed `scroll-conservatively' lines.
6850
6851 *** The new variable scroll-margin says how close point can come to the
6852 top or bottom of a window. It is a number of screen lines; if point
6853 comes within that many lines of the top or bottom of the window, Emacs
6854 recenters the window.
6855
6856 ** International character set support (MULE)
6857
6858 Emacs now supports a wide variety of international character sets,
6859 including European variants of the Latin alphabet, as well as Chinese,
6860 Devanagari (Hindi and Marathi), Ethiopian, Greek, IPA, Japanese,
6861 Korean, Lao, Russian, Thai, Tibetan, and Vietnamese scripts. These
6862 features have been merged from the modified version of Emacs known as
6863 MULE (for "MULti-lingual Enhancement to GNU Emacs")
6864
6865 Users of these scripts have established many more-or-less standard
6866 coding systems for storing files. Emacs uses a single multibyte
6867 character encoding within Emacs buffers; it can translate from a wide
6868 variety of coding systems when reading a file and can translate back
6869 into any of these coding systems when saving a file.
6870
6871 Keyboards, even in the countries where these character sets are used,
6872 generally don't have keys for all the characters in them. So Emacs
6873 supports various "input methods", typically one for each script or
6874 language, to make it possible to type them.
6875
6876 The Emacs internal multibyte encoding represents a non-ASCII
6877 character as a sequence of bytes in the range 0200 through 0377.
6878
6879 The new prefix key C-x RET is used for commands that pertain
6880 to multibyte characters, coding systems, and input methods.
6881
6882 You can disable multibyte character support as follows:
6883
6884 (setq-default enable-multibyte-characters nil)
6885
6886 Calling the function standard-display-european turns off multibyte
6887 characters, unless you specify a non-nil value for the second
6888 argument, AUTO. This provides compatibility for people who are
6889 already using standard-display-european to continue using unibyte
6890 characters for their work until they want to change.
6891
6892 *** Input methods
6893
6894 An input method is a kind of character conversion which is designed
6895 specifically for interactive input. In Emacs, typically each language
6896 has its own input method (though sometimes several languages which use
6897 the same characters can share one input method). Some languages
6898 support several input methods.
6899
6900 The simplest kind of input method works by mapping ASCII letters into
6901 another alphabet. This is how the Greek and Russian input methods
6902 work.
6903
6904 A more powerful technique is composition: converting sequences of
6905 characters into one letter. Many European input methods use
6906 composition to produce a single non-ASCII letter from a sequence which
6907 consists of a letter followed by diacritics. For example, a' is one
6908 sequence of two characters that might be converted into a single
6909 letter.
6910
6911 The input methods for syllabic scripts typically use mapping followed
6912 by conversion. The input methods for Thai and Korean work this way.
6913 First, letters are mapped into symbols for particular sounds or tone
6914 marks; then, sequences of these which make up a whole syllable are
6915 mapped into one syllable sign--most often a "composite character".
6916
6917 None of these methods works very well for Chinese and Japanese, so
6918 they are handled specially. First you input a whole word using
6919 phonetic spelling; then, after the word is in the buffer, Emacs
6920 converts it into one or more characters using a large dictionary.
6921
6922 Since there is more than one way to represent a phonetically spelled
6923 word using Chinese characters, Emacs can only guess which one to use;
6924 typically these input methods give you a way to say "guess again" if
6925 the first guess is wrong.
6926
6927 *** The command C-x RET m (toggle-enable-multibyte-characters)
6928 turns multibyte character support on or off for the current buffer.
6929
6930 If multibyte character support is turned off in a buffer, then each
6931 byte is a single character, even codes 0200 through 0377--exactly as
6932 they did in Emacs 19.34. This includes the features for support for
6933 the European characters, ISO Latin-1 and ISO Latin-2.
6934
6935 However, there is no need to turn off multibyte character support to
6936 use ISO Latin-1 or ISO Latin-2; the Emacs multibyte character set
6937 includes all the characters in these character sets, and Emacs can
6938 translate automatically to and from either one.
6939
6940 *** Visiting a file in unibyte mode.
6941
6942 Turning off multibyte character support in the buffer after visiting a
6943 file with multibyte code conversion will display the multibyte
6944 sequences already in the buffer, byte by byte. This is probably not
6945 what you want.
6946
6947 If you want to edit a file of unibyte characters (Latin-1, for
6948 example), you can do it by specifying `no-conversion' as the coding
6949 system when reading the file. This coding system also turns off
6950 multibyte characters in that buffer.
6951
6952 If you turn off multibyte character support entirely, this turns off
6953 character conversion as well.
6954
6955 *** Displaying international characters on X Windows.
6956
6957 A font for X typically displays just one alphabet or script.
6958 Therefore, displaying the entire range of characters Emacs supports
6959 requires using many fonts.
6960
6961 Therefore, Emacs now supports "fontsets". Each fontset is a
6962 collection of fonts, each assigned to a range of character codes.
6963
6964 A fontset has a name, like a font. Individual fonts are defined by
6965 the X server; fontsets are defined within Emacs itself. But once you
6966 have defined a fontset, you can use it in a face or a frame just as
6967 you would use a font.
6968
6969 If a fontset specifies no font for a certain character, or if it
6970 specifies a font that does not exist on your system, then it cannot
6971 display that character. It will display an empty box instead.
6972
6973 The fontset height and width are determined by the ASCII characters
6974 (that is, by the font in the fontset which is used for ASCII
6975 characters). If another font in the fontset has a different height,
6976 or the wrong width, then characters assigned to that font are clipped,
6977 and displayed within a box if highlight-wrong-size-font is non-nil.
6978
6979 *** Defining fontsets.
6980
6981 Emacs does not use any fontset by default. Its default font is still
6982 chosen as in previous versions. You can tell Emacs to use a fontset
6983 with the `-fn' option or the `Font' X resource.
6984
6985 Emacs creates a standard fontset automatically according to the value
6986 of standard-fontset-spec. This fontset's short name is
6987 `fontset-standard'. Bold, italic, and bold-italic variants of the
6988 standard fontset are created automatically.
6989
6990 If you specify a default ASCII font with the `Font' resource or `-fn'
6991 argument, a fontset is generated from it. This works by replacing the
6992 FOUNDARY, FAMILY, ADD_STYLE, and AVERAGE_WIDTH fields of the font name
6993 with `*' then using this to specify a fontset. This fontset's short
6994 name is `fontset-startup'.
6995
6996 Emacs checks resources of the form Fontset-N where N is 0, 1, 2...
6997 The resource value should have this form:
6998 FONTSET-NAME, [CHARSET-NAME:FONT-NAME]...
6999 FONTSET-NAME should have the form of a standard X font name, except:
7000 * most fields should be just the wild card "*".
7001 * the CHARSET_REGISTRY field should be "fontset"
7002 * the CHARSET_ENCODING field can be any nickname of the fontset.
7003 The construct CHARSET-NAME:FONT-NAME can be repeated any number
7004 of times; each time specifies the font for one character set.
7005 CHARSET-NAME should be the name of a character set, and FONT-NAME
7006 should specify an actual font to use for that character set.
7007
7008 Each of these fontsets has an alias which is made from the
7009 last two font name fields, CHARSET_REGISTRY and CHARSET_ENCODING.
7010 You can refer to the fontset by that alias or by its full name.
7011
7012 For any character sets that you don't mention, Emacs tries to choose a
7013 font by substituting into FONTSET-NAME. For instance, with the
7014 following resource,
7015 Emacs*Fontset-0: -*-fixed-medium-r-normal-*-24-*-*-*-*-*-fontset-24
7016 the font for ASCII is generated as below:
7017 -*-fixed-medium-r-normal-*-24-*-ISO8859-1
7018 Here is the substitution rule:
7019 Change CHARSET_REGISTRY and CHARSET_ENCODING to that of the charset
7020 defined in the variable x-charset-registries. For instance, ASCII has
7021 the entry (ascii . "ISO8859-1") in this variable. Then, reduce
7022 sequences of wild cards -*-...-*- with a single wildcard -*-.
7023 (This is to prevent use of auto-scaled fonts.)
7024
7025 The function which processes the fontset resource value to create the
7026 fontset is called create-fontset-from-fontset-spec. You can also call
7027 that function explicitly to create a fontset.
7028
7029 With the X resource Emacs.Font, you can specify a fontset name just
7030 like an actual font name. But be careful not to specify a fontset
7031 name in a wildcard resource like Emacs*Font--that tries to specify the
7032 fontset for other purposes including menus, and they cannot handle
7033 fontsets.
7034
7035 *** The command M-x set-language-environment sets certain global Emacs
7036 defaults for a particular choice of language.
7037
7038 Selecting a language environment typically specifies a default input
7039 method and which coding systems to recognize automatically when
7040 visiting files. However, it does not try to reread files you have
7041 already visited; the text in those buffers is not affected. The
7042 language environment may also specify a default choice of coding
7043 system for new files that you create.
7044
7045 It makes no difference which buffer is current when you use
7046 set-language-environment, because these defaults apply globally to the
7047 whole Emacs session.
7048
7049 For example, M-x set-language-environment RET Latin-1 RET
7050 chooses the Latin-1 character set. In the .emacs file, you can do this
7051 with (set-language-environment "Latin-1").
7052
7053 *** The command C-x RET f (set-buffer-file-coding-system)
7054 specifies the file coding system for the current buffer. This
7055 specifies what sort of character code translation to do when saving
7056 the file. As an argument, you must specify the name of one of the
7057 coding systems that Emacs supports.
7058
7059 *** The command C-x RET c (universal-coding-system-argument)
7060 lets you specify a coding system when you read or write a file.
7061 This command uses the minibuffer to read a coding system name.
7062 After you exit the minibuffer, the specified coding system
7063 is used for *the immediately following command*.
7064
7065 So if the immediately following command is a command to read or
7066 write a file, it uses the specified coding system for that file.
7067
7068 If the immediately following command does not use the coding system,
7069 then C-x RET c ultimately has no effect.
7070
7071 For example, C-x RET c iso-8859-1 RET C-x C-f temp RET
7072 visits the file `temp' treating it as ISO Latin-1.
7073
7074 *** You can specify the coding system for a file using the -*-
7075 construct. Include `coding: CODINGSYSTEM;' inside the -*-...-*-
7076 to specify use of coding system CODINGSYSTEM. You can also
7077 specify the coding system in a local variable list at the end
7078 of the file.
7079
7080 *** The command C-x RET t (set-terminal-coding-system) specifies
7081 the coding system for terminal output. If you specify a character
7082 code for terminal output, all characters output to the terminal are
7083 translated into that character code.
7084
7085 This feature is useful for certain character-only terminals built in
7086 various countries to support the languages of those countries.
7087
7088 By default, output to the terminal is not translated at all.
7089
7090 *** The command C-x RET k (set-keyboard-coding-system) specifies
7091 the coding system for keyboard input.
7092
7093 Character code translation of keyboard input is useful for terminals
7094 with keys that send non-ASCII graphic characters--for example,
7095 some terminals designed for ISO Latin-1 or subsets of it.
7096
7097 By default, keyboard input is not translated at all.
7098
7099 Character code translation of keyboard input is similar to using an
7100 input method, in that both define sequences of keyboard input that
7101 translate into single characters. However, input methods are designed
7102 to be convenient for interactive use, while the code translations are
7103 designed to work with terminals.
7104
7105 *** The command C-x RET p (set-buffer-process-coding-system)
7106 specifies the coding system for input and output to a subprocess.
7107 This command applies to the current buffer; normally, each subprocess
7108 has its own buffer, and thus you can use this command to specify
7109 translation to and from a particular subprocess by giving the command
7110 in the corresponding buffer.
7111
7112 By default, process input and output are not translated at all.
7113
7114 *** The variable file-name-coding-system specifies the coding system
7115 to use for encoding file names before operating on them.
7116 It is also used for decoding file names obtained from the system.
7117
7118 *** The command C-\ (toggle-input-method) activates or deactivates
7119 an input method. If no input method has been selected before, the
7120 command prompts for you to specify the language and input method you
7121 want to use.
7122
7123 C-u C-\ (select-input-method) lets you switch to a different input
7124 method. C-h C-\ (or C-h I) describes the current input method.
7125
7126 *** Some input methods remap the keyboard to emulate various keyboard
7127 layouts commonly used for particular scripts. How to do this
7128 remapping properly depends on your actual keyboard layout. To specify
7129 which layout your keyboard has, use M-x quail-set-keyboard-layout.
7130
7131 *** The command C-h C (describe-coding-system) displays
7132 the coding systems currently selected for various purposes, plus
7133 related information.
7134
7135 *** The command C-h h (view-hello-file) displays a file called
7136 HELLO, which has examples of text in many languages, using various
7137 scripts.
7138
7139 *** The command C-h L (describe-language-support) displays
7140 information about the support for a particular language.
7141 You specify the language as an argument.
7142
7143 *** The mode line now contains a letter or character that identifies
7144 the coding system used in the visited file. It normally follows the
7145 first dash.
7146
7147 A dash indicates the default state of affairs: no code conversion
7148 (except CRLF => newline if appropriate). `=' means no conversion
7149 whatsoever. The ISO 8859 coding systems are represented by digits
7150 1 through 9. Other coding systems are represented by letters:
7151
7152 A alternativnyj (Russian)
7153 B big5 (Chinese)
7154 C cn-gb-2312 (Chinese)
7155 C iso-2022-cn (Chinese)
7156 D in-is13194-devanagari (Indian languages)
7157 E euc-japan (Japanese)
7158 I iso-2022-cjk or iso-2022-ss2 (Chinese, Japanese, Korean)
7159 J junet (iso-2022-7) or old-jis (iso-2022-jp-1978-irv) (Japanese)
7160 K euc-korea (Korean)
7161 R koi8 (Russian)
7162 Q tibetan
7163 S shift_jis (Japanese)
7164 T lao
7165 T tis620 (Thai)
7166 V viscii or vscii (Vietnamese)
7167 i iso-2022-lock (Chinese, Japanese, Korean)
7168 k iso-2022-kr (Korean)
7169 v viqr (Vietnamese)
7170 z hz (Chinese)
7171
7172 When you are using a character-only terminal (not a window system),
7173 two additional characters appear in between the dash and the file
7174 coding system. These two characters describe the coding system for
7175 keyboard input, and the coding system for terminal output.
7176
7177 *** The new variable rmail-file-coding-system specifies the code
7178 conversion to use for RMAIL files. The default value is nil.
7179
7180 When you read mail with Rmail, each message is decoded automatically
7181 into Emacs' internal format. This has nothing to do with
7182 rmail-file-coding-system. That variable controls reading and writing
7183 Rmail files themselves.
7184
7185 *** The new variable sendmail-coding-system specifies the code
7186 conversion for outgoing mail. The default value is nil.
7187
7188 Actually, there are three different ways of specifying the coding system
7189 for sending mail:
7190
7191 - If you use C-x RET f in the mail buffer, that takes priority.
7192 - Otherwise, if you set sendmail-coding-system non-nil, that specifies it.
7193 - Otherwise, the default coding system for new files is used,
7194 if that is non-nil. That comes from your language environment.
7195 - Otherwise, Latin-1 is used.
7196
7197 *** The command C-h t (help-with-tutorial) accepts a prefix argument
7198 to specify the language for the tutorial file. Currently, English,
7199 Japanese, Korean and Thai are supported. We welcome additional
7200 translations.
7201
7202 ** An easy new way to visit a file with no code or format conversion
7203 of any kind: Use M-x find-file-literally. There is also a command
7204 insert-file-literally which inserts a file into the current buffer
7205 without any conversion.
7206
7207 ** C-q's handling of octal character codes is changed.
7208 You can now specify any number of octal digits.
7209 RET terminates the digits and is discarded;
7210 any other non-digit terminates the digits and is then used as input.
7211
7212 ** There are new commands for looking up Info documentation for
7213 functions, variables and file names used in your programs.
7214
7215 Type M-x info-lookup-symbol to look up a symbol in the buffer at point.
7216 Type M-x info-lookup-file to look up a file in the buffer at point.
7217
7218 Precisely which Info files are used to look it up depends on the major
7219 mode. For example, in C mode, the GNU libc manual is used.
7220
7221 ** M-TAB in most programming language modes now runs the command
7222 complete-symbol. This command performs completion on the symbol name
7223 in the buffer before point.
7224
7225 With a numeric argument, it performs completion based on the set of
7226 symbols documented in the Info files for the programming language that
7227 you are using.
7228
7229 With no argument, it does completion based on the current tags tables,
7230 just like the old binding of M-TAB (complete-tag).
7231
7232 ** File locking works with NFS now.
7233
7234 The lock file for FILENAME is now a symbolic link named .#FILENAME,
7235 in the same directory as FILENAME.
7236
7237 This means that collision detection between two different machines now
7238 works reasonably well; it also means that no file server or directory
7239 can become a bottleneck.
7240
7241 The new method does have drawbacks. It means that collision detection
7242 does not operate when you edit a file in a directory where you cannot
7243 create new files. Collision detection also doesn't operate when the
7244 file server does not support symbolic links. But these conditions are
7245 rare, and the ability to have collision detection while using NFS is
7246 so useful that the change is worth while.
7247
7248 When Emacs or a system crashes, this may leave behind lock files which
7249 are stale. So you may occasionally get warnings about spurious
7250 collisions. When you determine that the collision is spurious, just
7251 tell Emacs to go ahead anyway.
7252
7253 ** If you wish to use Show Paren mode to display matching parentheses,
7254 it is no longer sufficient to load paren.el. Instead you must call
7255 show-paren-mode.
7256
7257 ** If you wish to use Delete Selection mode to replace a highlighted
7258 selection when you insert new text, it is no longer sufficient to load
7259 delsel.el. Instead you must call the function delete-selection-mode.
7260
7261 ** If you wish to use Partial Completion mode to complete partial words
7262 within symbols or filenames, it is no longer sufficient to load
7263 complete.el. Instead you must call the function partial-completion-mode.
7264
7265 ** If you wish to use uniquify to rename buffers for you,
7266 it is no longer sufficient to load uniquify.el. You must also
7267 set uniquify-buffer-name-style to one of the non-nil legitimate values.
7268
7269 ** Changes in View mode.
7270
7271 *** Several new commands are available in View mode.
7272 Do H in view mode for a list of commands.
7273
7274 *** There are two new commands for entering View mode:
7275 view-file-other-frame and view-buffer-other-frame.
7276
7277 *** Exiting View mode does a better job of restoring windows to their
7278 previous state.
7279
7280 *** New customization variable view-scroll-auto-exit. If non-nil,
7281 scrolling past end of buffer makes view mode exit.
7282
7283 *** New customization variable view-exits-all-viewing-windows. If
7284 non-nil, view-mode will at exit restore all windows viewing buffer,
7285 not just the selected window.
7286
7287 *** New customization variable view-read-only. If non-nil, visiting a
7288 read-only file automatically enters View mode, and toggle-read-only
7289 turns View mode on or off.
7290
7291 *** New customization variable view-remove-frame-by-deleting controls
7292 how to remove a not needed frame at view mode exit. If non-nil,
7293 delete the frame, if nil make an icon of it.
7294
7295 ** C-x v l, the command to print a file's version control log,
7296 now positions point at the entry for the file's current branch version.
7297
7298 ** C-x v =, the command to compare a file with the last checked-in version,
7299 has a new feature. If the file is currently not locked, so that it is
7300 presumably identical to the last checked-in version, the command now asks
7301 which version to compare with.
7302
7303 ** When using hideshow.el, incremental search can temporarily show hidden
7304 blocks if a match is inside the block.
7305
7306 The block is hidden again if the search is continued and the next match
7307 is outside the block. By customizing the variable
7308 isearch-hide-immediately you can choose to hide all the temporarily
7309 shown blocks only when exiting from incremental search.
7310
7311 By customizing the variable hs-isearch-open you can choose what kind
7312 of blocks to temporarily show during isearch: comment blocks, code
7313 blocks, all of them or none.
7314
7315 ** The new command C-x 4 0 (kill-buffer-and-window) kills the
7316 current buffer and deletes the selected window. It asks for
7317 confirmation first.
7318
7319 ** C-x C-w, which saves the buffer into a specified file name,
7320 now changes the major mode according to that file name.
7321 However, the mode will not be changed if
7322 (1) a local variables list or the `-*-' line specifies a major mode, or
7323 (2) the current major mode is a "special" mode,
7324 not suitable for ordinary files, or
7325 (3) the new file name does not particularly specify any mode.
7326
7327 This applies to M-x set-visited-file-name as well.
7328
7329 However, if you set change-major-mode-with-file-name to nil, then
7330 these commands do not change the major mode.
7331
7332 ** M-x occur changes.
7333
7334 *** If the argument to M-x occur contains upper case letters,
7335 it performs a case-sensitive search.
7336
7337 *** In the *Occur* buffer made by M-x occur,
7338 if you type g or M-x revert-buffer, this repeats the search
7339 using the same regular expression and the same buffer as before.
7340
7341 ** In Transient Mark mode, the region in any one buffer is highlighted
7342 in just one window at a time. At first, it is highlighted in the
7343 window where you set the mark. The buffer's highlighting remains in
7344 that window unless you select to another window which shows the same
7345 buffer--then the highlighting moves to that window.
7346
7347 ** The feature to suggest key bindings when you use M-x now operates
7348 after the command finishes. The message suggesting key bindings
7349 appears temporarily in the echo area. The previous echo area contents
7350 come back after a few seconds, in case they contain useful information.
7351
7352 ** Each frame now independently records the order for recently
7353 selected buffers, so that the default for C-x b is now based on the
7354 buffers recently selected in the selected frame.
7355
7356 ** Outline mode changes.
7357
7358 *** Outline mode now uses overlays (this is the former noutline.el).
7359
7360 *** Incremental searches skip over invisible text in Outline mode.
7361
7362 ** When a minibuffer window is active but not the selected window, if
7363 you try to use the minibuffer, you used to get a nested minibuffer.
7364 Now, this not only gives an error, it also cancels the minibuffer that
7365 was already active.
7366
7367 The motive for this change is so that beginning users do not
7368 unknowingly move away from minibuffers, leaving them active, and then
7369 get confused by it.
7370
7371 If you want to be able to have recursive minibuffers, you must
7372 set enable-recursive-minibuffers to non-nil.
7373
7374 ** Changes in dynamic abbrevs.
7375
7376 *** Expanding dynamic abbrevs with M-/ is now smarter about case
7377 conversion. If the expansion has mixed case not counting the first
7378 character, and the abbreviation matches the beginning of the expansion
7379 including case, then the expansion is copied verbatim.
7380
7381 The expansion is also copied verbatim if the abbreviation itself has
7382 mixed case. And using SPC M-/ to copy an additional word always
7383 copies it verbatim except when the previous copied word is all caps.
7384
7385 *** The values of `dabbrev-case-replace' and `dabbrev-case-fold-search'
7386 are no longer Lisp expressions. They have simply three possible
7387 values.
7388
7389 `dabbrev-case-replace' has these three values: nil (don't preserve
7390 case), t (do), or `case-replace' (do like M-x query-replace).
7391 `dabbrev-case-fold-search' has these three values: nil (don't ignore
7392 case), t (do), or `case-fold-search' (do like search).
7393
7394 ** Minibuffer history lists are truncated automatically now to a
7395 certain length. The variable history-length specifies how long they
7396 can be. The default value is 30.
7397
7398 ** Changes in Mail mode.
7399
7400 *** The key C-x m no longer runs the `mail' command directly.
7401 Instead, it runs the command `compose-mail', which invokes the mail
7402 composition mechanism you have selected with the variable
7403 `mail-user-agent'. The default choice of user agent is
7404 `sendmail-user-agent', which gives behavior compatible with the old
7405 behavior.
7406
7407 C-x 4 m now runs compose-mail-other-window, and C-x 5 m runs
7408 compose-mail-other-frame.
7409
7410 *** While composing a reply to a mail message, from Rmail, you can use
7411 the command C-c C-r to cite just the region from the message you are
7412 replying to. This copies the text which is the selected region in the
7413 buffer that shows the original message.
7414
7415 *** The command C-c C-i inserts a file at the end of the message,
7416 with separator lines around the contents.
7417
7418 *** The command M-x expand-mail-aliases expands all mail aliases
7419 in suitable mail headers. Emacs automatically extracts mail alias
7420 definitions from your mail alias file (e.g., ~/.mailrc). You do not
7421 need to expand mail aliases yourself before sending mail.
7422
7423 *** New features in the mail-complete command.
7424
7425 **** The mail-complete command now inserts the user's full name,
7426 for local users or if that is known. The variable mail-complete-style
7427 controls the style to use, and whether to do this at all.
7428 Its values are like those of mail-from-style.
7429
7430 **** The variable mail-passwd-command lets you specify a shell command
7431 to run to fetch a set of password-entries that add to the ones in
7432 /etc/passwd.
7433
7434 **** The variable mail-passwd-file now specifies a list of files to read
7435 to get the list of user ids. By default, one file is used:
7436 /etc/passwd.
7437
7438 ** You can "quote" a file name to inhibit special significance of
7439 special syntax, by adding `/:' to the beginning. Thus, if you have a
7440 directory named `/foo:', you can prevent it from being treated as a
7441 reference to a remote host named `foo' by writing it as `/:/foo:'.
7442
7443 Emacs uses this new construct automatically when necessary, such as
7444 when you start it with a working directory whose name might otherwise
7445 be taken to be magic.
7446
7447 ** There is a new command M-x grep-find which uses find to select
7448 files to search through, and grep to scan them. The output is
7449 available in a Compile mode buffer, as with M-x grep.
7450
7451 M-x grep now uses the -e option if the grep program supports that.
7452 (-e prevents problems if the search pattern starts with a dash.)
7453
7454 ** In Dired, the & command now flags for deletion the files whose names
7455 suggest they are probably not needed in the long run.
7456
7457 In Dired, * is now a prefix key for mark-related commands.
7458
7459 new key dired.el binding old key
7460 ------- ---------------- -------
7461 * c dired-change-marks c
7462 * m dired-mark m
7463 * * dired-mark-executables * (binding deleted)
7464 * / dired-mark-directories / (binding deleted)
7465 * @ dired-mark-symlinks @ (binding deleted)
7466 * u dired-unmark u
7467 * DEL dired-unmark-backward DEL
7468 * ? dired-unmark-all-files C-M-?
7469 * ! dired-unmark-all-marks
7470 * % dired-mark-files-regexp % m
7471 * C-n dired-next-marked-file M-}
7472 * C-p dired-prev-marked-file M-{
7473
7474 ** Rmail changes.
7475
7476 *** When Rmail cannot convert your incoming mail into Babyl format, it
7477 saves the new mail in the file RMAILOSE.n, where n is an integer
7478 chosen to make a unique name. This way, Rmail will not keep crashing
7479 each time you run it.
7480
7481 *** In Rmail, the variable rmail-summary-line-count-flag now controls
7482 whether to include the line count in the summary. Non-nil means yes.
7483
7484 *** In Rmail summary buffers, d and C-d (the commands to delete
7485 messages) now take repeat counts as arguments. A negative argument
7486 means to move in the opposite direction.
7487
7488 *** In Rmail, the t command now takes an optional argument which lets
7489 you specify whether to show the message headers in full or pruned.
7490
7491 *** In Rmail, the new command w (rmail-output-body-to-file) writes
7492 just the body of the current message into a file, without the headers.
7493 It takes the file name from the message subject, by default, but you
7494 can edit that file name in the minibuffer before it is actually used
7495 for output.
7496
7497 ** Gnus changes.
7498
7499 *** nntp.el has been totally rewritten in an asynchronous fashion.
7500
7501 *** Article prefetching functionality has been moved up into
7502 Gnus.
7503
7504 *** Scoring can now be performed with logical operators like
7505 `and', `or', `not', and parent redirection.
7506
7507 *** Article washing status can be displayed in the
7508 article mode line.
7509
7510 *** gnus.el has been split into many smaller files.
7511
7512 *** Suppression of duplicate articles based on Message-ID.
7513
7514 (setq gnus-suppress-duplicates t)
7515
7516 *** New variables for specifying what score and adapt files
7517 are to be considered home score and adapt files. See
7518 `gnus-home-score-file' and `gnus-home-adapt-files'.
7519
7520 *** Groups can inherit group parameters from parent topics.
7521
7522 *** Article editing has been revamped and is now usable.
7523
7524 *** Signatures can be recognized in more intelligent fashions.
7525 See `gnus-signature-separator' and `gnus-signature-limit'.
7526
7527 *** Summary pick mode has been made to look more nn-like.
7528 Line numbers are displayed and the `.' command can be
7529 used to pick articles.
7530
7531 *** Commands for moving the .newsrc.eld from one server to
7532 another have been added.
7533
7534 `M-x gnus-change-server'
7535
7536 *** A way to specify that "uninteresting" fields be suppressed when
7537 generating lines in buffers.
7538
7539 *** Several commands in the group buffer can be undone with
7540 `C-M-_'.
7541
7542 *** Scoring can be done on words using the new score type `w'.
7543
7544 *** Adaptive scoring can be done on a Subject word-by-word basis:
7545
7546 (setq gnus-use-adaptive-scoring '(word))
7547
7548 *** Scores can be decayed.
7549
7550 (setq gnus-decay-scores t)
7551
7552 *** Scoring can be performed using a regexp on the Date header. The
7553 Date is normalized to compact ISO 8601 format first.
7554
7555 *** A new command has been added to remove all data on articles from
7556 the native server.
7557
7558 `M-x gnus-group-clear-data-on-native-groups'
7559
7560 *** A new command for reading collections of documents
7561 (nndoc with nnvirtual on top) has been added -- `C-M-d'.
7562
7563 *** Process mark sets can be pushed and popped.
7564
7565 *** A new mail-to-news backend makes it possible to post
7566 even when the NNTP server doesn't allow posting.
7567
7568 *** A new backend for reading searches from Web search engines
7569 (DejaNews, Alta Vista, InReference) has been added.
7570
7571 Use the `G w' command in the group buffer to create such
7572 a group.
7573
7574 *** Groups inside topics can now be sorted using the standard
7575 sorting functions, and each topic can be sorted independently.
7576
7577 See the commands under the `T S' submap.
7578
7579 *** Subsets of the groups can be sorted independently.
7580
7581 See the commands under the `G P' submap.
7582
7583 *** Cached articles can be pulled into the groups.
7584
7585 Use the `Y c' command.
7586
7587 *** Score files are now applied in a more reliable order.
7588
7589 *** Reports on where mail messages end up can be generated.
7590
7591 `M-x nnmail-split-history'
7592
7593 *** More hooks and functions have been added to remove junk
7594 from incoming mail before saving the mail.
7595
7596 See `nnmail-prepare-incoming-header-hook'.
7597
7598 *** The nnml mail backend now understands compressed article files.
7599
7600 *** To enable Gnus to read/post multi-lingual articles, you must execute
7601 the following code, for instance, in your .emacs.
7602
7603 (add-hook 'gnus-startup-hook 'gnus-mule-initialize)
7604
7605 Then, when you start Gnus, it will decode non-ASCII text automatically
7606 and show appropriate characters. (Note: if you are using gnus-mime
7607 from the SEMI package, formerly known as TM, you should NOT add this
7608 hook to gnus-startup-hook; gnus-mime has its own method of handling
7609 this issue.)
7610
7611 Since it is impossible to distinguish all coding systems
7612 automatically, you may need to specify a choice of coding system for a
7613 particular news group. This can be done by:
7614
7615 (gnus-mule-add-group NEWSGROUP 'CODING-SYSTEM)
7616
7617 Here NEWSGROUP should be a string which names a newsgroup or a tree
7618 of newsgroups. If NEWSGROUP is "XXX.YYY", all news groups under
7619 "XXX.YYY" (including "XXX.YYY.ZZZ") will use the specified coding
7620 system. CODING-SYSTEM specifies which coding system to use (for both
7621 for reading and posting).
7622
7623 CODING-SYSTEM can also be a cons cell of the form
7624 (READ-CODING-SYSTEM . POST-CODING-SYSTEM)
7625 Then READ-CODING-SYSTEM is used when you read messages from the
7626 newsgroups, while POST-CODING-SYSTEM is used when you post messages
7627 there.
7628
7629 Emacs knows the right coding systems for certain newsgroups by
7630 default. Here are some of these default settings:
7631
7632 (gnus-mule-add-group "fj" 'iso-2022-7)
7633 (gnus-mule-add-group "alt.chinese.text" 'hz-gb-2312)
7634 (gnus-mule-add-group "alt.hk" 'hz-gb-2312)
7635 (gnus-mule-add-group "alt.chinese.text.big5" 'cn-big5)
7636 (gnus-mule-add-group "soc.culture.vietnamese" '(nil . viqr))
7637
7638 When you reply by mail to an article, these settings are ignored;
7639 the mail is encoded according to sendmail-coding-system, as usual.
7640
7641 ** CC mode changes.
7642
7643 *** If you edit primarily one style of C (or C++, Objective-C, Java)
7644 code, you may want to make the CC Mode style variables have global
7645 values so that you can set them directly in your .emacs file. To do
7646 this, set c-style-variables-are-local-p to nil in your .emacs file.
7647 Note that this only takes effect if you do it *before* cc-mode.el is
7648 loaded.
7649
7650 If you typically edit more than one style of C (or C++, Objective-C,
7651 Java) code in a single Emacs session, you may want to make the CC Mode
7652 style variables have buffer local values. By default, all buffers
7653 share the same style variable settings; to make them buffer local, set
7654 c-style-variables-are-local-p to t in your .emacs file. Note that you
7655 must do this *before* CC Mode is loaded.
7656
7657 *** The new variable c-indentation-style holds the C style name
7658 of the current buffer.
7659
7660 *** The variable c-block-comments-indent-p has been deleted, because
7661 it is no longer necessary. C mode now handles all the supported styles
7662 of block comments, with no need to say which one you will use.
7663
7664 *** There is a new indentation style "python", which specifies the C
7665 style that the Python developers like.
7666
7667 *** There is a new c-cleanup-list option: brace-elseif-brace.
7668 This says to put ...} else if (...) {... on one line,
7669 just as brace-else-brace says to put ...} else {... on one line.
7670
7671 ** VC Changes [new]
7672
7673 *** In vc-retrieve-snapshot (C-x v r), if you don't specify a snapshot
7674 name, it retrieves the *latest* versions of all files in the current
7675 directory and its subdirectories (aside from files already locked).
7676
7677 This feature is useful if your RCS directory is a link to a common
7678 master directory, and you want to pick up changes made by other
7679 developers.
7680
7681 You can do the same thing for an individual file by typing C-u C-x C-q
7682 RET in a buffer visiting that file.
7683
7684 *** VC can now handle files under CVS that are being "watched" by
7685 other developers. Such files are made read-only by CVS. To get a
7686 writable copy, type C-x C-q in a buffer visiting such a file. VC then
7687 calls "cvs edit", which notifies the other developers of it.
7688
7689 *** vc-version-diff (C-u C-x v =) now suggests reasonable defaults for
7690 version numbers, based on the current state of the file.
7691
7692 ** Calendar changes.
7693
7694 *** A new function, list-holidays, allows you list holidays or
7695 subclasses of holidays for ranges of years. Related menu items allow
7696 you do this for the year of the selected date, or the
7697 following/previous years.
7698
7699 *** There is now support for the Baha'i calendar system. Use `pb' in
7700 the *Calendar* buffer to display the current Baha'i date. The Baha'i
7701 calendar, or "Badi calendar" is a system of 19 months with 19 days
7702 each, and 4 intercalary days (5 during a Gregorian leap year). The
7703 calendar begins May 23, 1844, with each of the months named after a
7704 supposed attribute of God.
7705
7706 ** ps-print changes
7707
7708 There are some new user variables and subgroups for customizing the page
7709 layout.
7710
7711 *** Headers & Footers (subgroup)
7712
7713 Some printer systems print a header page and force the first page to
7714 be printed on the back of the header page when using duplex. If your
7715 printer system has this behavior, set variable
7716 `ps-banner-page-when-duplexing' to t.
7717
7718 If variable `ps-banner-page-when-duplexing' is non-nil, it prints a
7719 blank page as the very first printed page. So, it behaves as if the
7720 very first character of buffer (or region) were a form feed ^L (\014).
7721
7722 The variable `ps-spool-config' specifies who is responsible for
7723 setting duplex mode and page size. Valid values are:
7724
7725 lpr-switches duplex and page size are configured by `ps-lpr-switches'.
7726 Don't forget to set `ps-lpr-switches' to select duplex
7727 printing for your printer.
7728
7729 setpagedevice duplex and page size are configured by ps-print using the
7730 setpagedevice PostScript operator.
7731
7732 nil duplex and page size are configured by ps-print *not* using
7733 the setpagedevice PostScript operator.
7734
7735 The variable `ps-spool-tumble' specifies how the page images on
7736 opposite sides of a sheet are oriented with respect to each other. If
7737 `ps-spool-tumble' is nil, ps-print produces output suitable for
7738 bindings on the left or right. If `ps-spool-tumble' is non-nil,
7739 ps-print produces output suitable for bindings at the top or bottom.
7740 This variable takes effect only if `ps-spool-duplex' is non-nil.
7741 The default value is nil.
7742
7743 The variable `ps-header-frame-alist' specifies a header frame
7744 properties alist. Valid frame properties are:
7745
7746 fore-color Specify the foreground frame color.
7747 Value should be a float number between 0.0 (black
7748 color) and 1.0 (white color), or a string which is a
7749 color name, or a list of 3 float numbers which
7750 correspond to the Red Green Blue color scale, each
7751 float number between 0.0 (dark color) and 1.0 (bright
7752 color). The default is 0 ("black").
7753
7754 back-color Specify the background frame color (similar to fore-color).
7755 The default is 0.9 ("gray90").
7756
7757 shadow-color Specify the shadow color (similar to fore-color).
7758 The default is 0 ("black").
7759
7760 border-color Specify the border color (similar to fore-color).
7761 The default is 0 ("black").
7762
7763 border-width Specify the border width.
7764 The default is 0.4.
7765
7766 Any other property is ignored.
7767
7768 Don't change this alist directly; instead use Custom, or the
7769 `ps-value', `ps-get', `ps-put' and `ps-del' functions (see there for
7770 documentation).
7771
7772 Ps-print can also print footers. The footer variables are:
7773 `ps-print-footer', `ps-footer-offset', `ps-print-footer-frame',
7774 `ps-footer-font-family', `ps-footer-font-size', `ps-footer-line-pad',
7775 `ps-footer-lines', `ps-left-footer', `ps-right-footer' and
7776 `ps-footer-frame-alist'. These variables are similar to those
7777 controlling headers.
7778
7779 *** Color management (subgroup)
7780
7781 If `ps-print-color-p' is non-nil, the buffer's text will be printed in
7782 color.
7783
7784 *** Face Management (subgroup)
7785
7786 If you need to print without worrying about face background colors,
7787 set the variable `ps-use-face-background' which specifies if face
7788 background should be used. Valid values are:
7789
7790 t always use face background color.
7791 nil never use face background color.
7792 (face...) list of faces whose background color will be used.
7793
7794 *** N-up printing (subgroup)
7795
7796 The variable `ps-n-up-printing' specifies the number of pages per
7797 sheet of paper.
7798
7799 The variable `ps-n-up-margin' specifies the margin in points (pt)
7800 between the sheet border and the n-up printing.
7801
7802 If variable `ps-n-up-border-p' is non-nil, a border is drawn around
7803 each page.
7804
7805 The variable `ps-n-up-filling' specifies how the page matrix is filled
7806 on each sheet of paper. Following are the valid values for
7807 `ps-n-up-filling' with a filling example using a 3x4 page matrix:
7808
7809 `left-top' 1 2 3 4 `left-bottom' 9 10 11 12
7810 5 6 7 8 5 6 7 8
7811 9 10 11 12 1 2 3 4
7812
7813 `right-top' 4 3 2 1 `right-bottom' 12 11 10 9
7814 8 7 6 5 8 7 6 5
7815 12 11 10 9 4 3 2 1
7816
7817 `top-left' 1 4 7 10 `bottom-left' 3 6 9 12
7818 2 5 8 11 2 5 8 11
7819 3 6 9 12 1 4 7 10
7820
7821 `top-right' 10 7 4 1 `bottom-right' 12 9 6 3
7822 11 8 5 2 11 8 5 2
7823 12 9 6 3 10 7 4 1
7824
7825 Any other value is treated as `left-top'.
7826
7827 *** Zebra stripes (subgroup)
7828
7829 The variable `ps-zebra-color' controls the zebra stripes grayscale or
7830 RGB color.
7831
7832 The variable `ps-zebra-stripe-follow' specifies how zebra stripes
7833 continue on next page. Visually, valid values are (the character `+'
7834 to the right of each column indicates that a line is printed):
7835
7836 `nil' `follow' `full' `full-follow'
7837 Current Page -------- ----------- --------- ----------------
7838 1 XXXXX + 1 XXXXXXXX + 1 XXXXXX + 1 XXXXXXXXXXXXX +
7839 2 XXXXX + 2 XXXXXXXX + 2 XXXXXX + 2 XXXXXXXXXXXXX +
7840 3 XXXXX + 3 XXXXXXXX + 3 XXXXXX + 3 XXXXXXXXXXXXX +
7841 4 + 4 + 4 + 4 +
7842 5 + 5 + 5 + 5 +
7843 6 + 6 + 6 + 6 +
7844 7 XXXXX + 7 XXXXXXXX + 7 XXXXXX + 7 XXXXXXXXXXXXX +
7845 8 XXXXX + 8 XXXXXXXX + 8 XXXXXX + 8 XXXXXXXXXXXXX +
7846 9 XXXXX + 9 XXXXXXXX + 9 XXXXXX + 9 XXXXXXXXXXXXX +
7847 10 + 10 +
7848 11 + 11 +
7849 -------- ----------- --------- ----------------
7850 Next Page -------- ----------- --------- ----------------
7851 12 XXXXX + 12 + 10 XXXXXX + 10 +
7852 13 XXXXX + 13 XXXXXXXX + 11 XXXXXX + 11 +
7853 14 XXXXX + 14 XXXXXXXX + 12 XXXXXX + 12 +
7854 15 + 15 XXXXXXXX + 13 + 13 XXXXXXXXXXXXX +
7855 16 + 16 + 14 + 14 XXXXXXXXXXXXX +
7856 17 + 17 + 15 + 15 XXXXXXXXXXXXX +
7857 18 XXXXX + 18 + 16 XXXXXX + 16 +
7858 19 XXXXX + 19 XXXXXXXX + 17 XXXXXX + 17 +
7859 20 XXXXX + 20 XXXXXXXX + 18 XXXXXX + 18 +
7860 21 + 21 XXXXXXXX +
7861 22 + 22 +
7862 -------- ----------- --------- ----------------
7863
7864 Any other value is treated as `nil'.
7865
7866
7867 *** Printer management (subgroup)
7868
7869 The variable `ps-printer-name-option' determines the option used by
7870 some utilities to indicate the printer name; it's used only when
7871 `ps-printer-name' is a non-empty string. If you're using the lpr
7872 utility to print, for example, `ps-printer-name-option' should be set
7873 to "-P".
7874
7875 The variable `ps-manual-feed' indicates if the printer requires manual
7876 paper feeding. If it's nil, automatic feeding takes place. If it's
7877 non-nil, manual feeding takes place.
7878
7879 The variable `ps-end-with-control-d' specifies whether C-d (\x04)
7880 should be inserted at end of the generated PostScript. Non-nil means
7881 do so.
7882
7883 *** Page settings (subgroup)
7884
7885 If variable `ps-warn-paper-type' is nil, it's *not* treated as an
7886 error if the PostScript printer doesn't have a paper with the size
7887 indicated by `ps-paper-type'; the default paper size will be used
7888 instead. If `ps-warn-paper-type' is non-nil, an error is signaled if
7889 the PostScript printer doesn't support a paper with the size indicated
7890 by `ps-paper-type'. This is used when `ps-spool-config' is set to
7891 `setpagedevice'.
7892
7893 The variable `ps-print-upside-down' determines the orientation for
7894 printing pages: nil means `normal' printing, non-nil means
7895 `upside-down' printing (that is, the page is rotated by 180 degrees).
7896
7897 The variable `ps-selected-pages' specifies which pages to print. If
7898 it's nil, all pages are printed. If it's a list, list elements may be
7899 integers specifying a single page to print, or cons cells (FROM . TO)
7900 specifying to print from page FROM to TO. Invalid list elements, that
7901 is integers smaller than one, or elements whose FROM is greater than
7902 its TO, are ignored.
7903
7904 The variable `ps-even-or-odd-pages' specifies how to print even/odd
7905 pages. Valid values are:
7906
7907 nil print all pages.
7908
7909 `even-page' print only even pages.
7910
7911 `odd-page' print only odd pages.
7912
7913 `even-sheet' print only even sheets.
7914 That is, if `ps-n-up-printing' is 1, it behaves like
7915 `even-page', but for values greater than 1, it'll
7916 print only the even sheet of paper.
7917
7918 `odd-sheet' print only odd sheets.
7919 That is, if `ps-n-up-printing' is 1, it behaves like
7920 `odd-page'; but for values greater than 1, it'll print
7921 only the odd sheet of paper.
7922
7923 Any other value is treated as nil.
7924
7925 If you set `ps-selected-pages' (see there for documentation), pages
7926 are filtered by `ps-selected-pages', and then by
7927 `ps-even-or-odd-pages'. For example, if we have:
7928
7929 (setq ps-selected-pages '(1 4 (6 . 10) (12 . 16) 20))
7930
7931 and we combine this with `ps-even-or-odd-pages' and
7932 `ps-n-up-printing', we get:
7933
7934 `ps-n-up-printing' = 1:
7935 `ps-even-or-odd-pages' PAGES PRINTED
7936 nil 1, 4, 6, 7, 8, 9, 10, 12, 13, 14, 15, 16, 20
7937 even-page 4, 6, 8, 10, 12, 14, 16, 20
7938 odd-page 1, 7, 9, 13, 15
7939 even-sheet 4, 6, 8, 10, 12, 14, 16, 20
7940 odd-sheet 1, 7, 9, 13, 15
7941
7942 `ps-n-up-printing' = 2:
7943 `ps-even-or-odd-pages' PAGES PRINTED
7944 nil 1/4, 6/7, 8/9, 10/12, 13/14, 15/16, 20
7945 even-page 4/6, 8/10, 12/14, 16/20
7946 odd-page 1/7, 9/13, 15
7947 even-sheet 6/7, 10/12, 15/16
7948 odd-sheet 1/4, 8/9, 13/14, 20
7949
7950 *** Miscellany (subgroup)
7951
7952 The variable `ps-error-handler-message' specifies where error handler
7953 messages should be sent.
7954
7955 It is also possible to add a user-defined PostScript prologue code in
7956 front of all generated prologue code by setting the variable
7957 `ps-user-defined-prologue'.
7958
7959 The variable `ps-line-number-font' specifies the font for line numbers.
7960
7961 The variable `ps-line-number-font-size' specifies the font size in
7962 points for line numbers.
7963
7964 The variable `ps-line-number-color' specifies the color for line
7965 numbers. See `ps-zebra-color' for documentation.
7966
7967 The variable `ps-line-number-step' specifies the interval in which
7968 line numbers are printed. For example, if `ps-line-number-step' is set
7969 to 2, the printing will look like:
7970
7971 1 one line
7972 one line
7973 3 one line
7974 one line
7975 5 one line
7976 one line
7977 ...
7978
7979 Valid values are:
7980
7981 integer an integer specifying the interval in which line numbers are
7982 printed. If it's smaller than or equal to zero, 1
7983 is used.
7984
7985 `zebra' specifies that only the line number of the first line in a
7986 zebra stripe is to be printed.
7987
7988 Any other value is treated as `zebra'.
7989
7990 The variable `ps-line-number-start' specifies the starting point in
7991 the interval given by `ps-line-number-step'. For example, if
7992 `ps-line-number-step' is set to 3, and `ps-line-number-start' is set to
7993 3, the output will look like:
7994
7995 one line
7996 one line
7997 3 one line
7998 one line
7999 one line
8000 6 one line
8001 one line
8002 one line
8003 9 one line
8004 one line
8005 ...
8006
8007 The variable `ps-postscript-code-directory' specifies the directory
8008 where the PostScript prologue file used by ps-print is found.
8009
8010 The variable `ps-line-spacing' determines the line spacing in points,
8011 for ordinary text, when generating PostScript (similar to
8012 `ps-font-size').
8013
8014 The variable `ps-paragraph-spacing' determines the paragraph spacing,
8015 in points, for ordinary text, when generating PostScript (similar to
8016 `ps-font-size').
8017
8018 The variable `ps-paragraph-regexp' specifies the paragraph delimiter.
8019
8020 The variable `ps-begin-cut-regexp' and `ps-end-cut-regexp' specify the
8021 start and end of a region to cut out when printing.
8022
8023 ** hideshow changes.
8024
8025 *** now supports hiding of blocks of single line comments (like // for
8026 C++, ; for lisp).
8027
8028 *** Support for java-mode added.
8029
8030 *** When doing `hs-hide-all' it is now possible to also hide the comments
8031 in the file if `hs-hide-comments-when-hiding-all' is set.
8032
8033 *** The new function `hs-hide-initial-comment' hides the comments at
8034 the beginning of the files. Finally those huge RCS logs don't stay in your
8035 way! This is run by default when entering the `hs-minor-mode'.
8036
8037 *** Now uses overlays instead of `selective-display', so is more
8038 robust and a lot faster.
8039
8040 *** A block beginning can span multiple lines.
8041
8042 *** The new variable `hs-show-hidden-short-form' if t, directs hideshow
8043 to show only the beginning of a block when it is hidden. See the
8044 documentation for more details.
8045
8046 ** Changes in Enriched mode.
8047
8048 *** When you visit a file in enriched-mode, Emacs will make sure it is
8049 filled to the current fill-column. This behavior is now independent
8050 of the size of the window. When you save the file, the fill-column in
8051 use is stored as well, so that the whole buffer need not be refilled
8052 the next time unless the fill-column is different.
8053
8054 *** use-hard-newlines is now a minor mode. When it is enabled, Emacs
8055 distinguishes between hard and soft newlines, and treats hard newlines
8056 as paragraph boundaries. Otherwise all newlines inserted are marked
8057 as soft, and paragraph boundaries are determined solely from the text.
8058
8059 ** Font Lock mode
8060
8061 *** Custom support
8062
8063 The variables font-lock-face-attributes, font-lock-display-type and
8064 font-lock-background-mode are now obsolete; the recommended way to specify the
8065 faces to use for Font Lock mode is with M-x customize-group on the new custom
8066 group font-lock-highlighting-faces. If you set font-lock-face-attributes in
8067 your ~/.emacs file, Font Lock mode will respect its value. However, you should
8068 consider converting from setting that variable to using M-x customize.
8069
8070 You can still use X resources to specify Font Lock face appearances.
8071
8072 *** Maximum decoration
8073
8074 Fontification now uses the maximum level of decoration supported by
8075 default. Previously, fontification used a mode-specific default level
8076 of decoration, which is typically the minimum level of decoration
8077 supported. You can set font-lock-maximum-decoration to nil
8078 to get the old behavior.
8079
8080 *** New support
8081
8082 Support is now provided for Java, Objective-C, AWK and SIMULA modes.
8083
8084 Note that Font Lock mode can be turned on without knowing exactly what modes
8085 support Font Lock mode, via the command global-font-lock-mode.
8086
8087 *** Configurable support
8088
8089 Support for C, C++, Objective-C and Java can be more easily configured for
8090 additional types and classes via the new variables c-font-lock-extra-types,
8091 c++-font-lock-extra-types, objc-font-lock-extra-types and, you guessed it,
8092 java-font-lock-extra-types. These value of each of these variables should be a
8093 list of regexps matching the extra type names. For example, the default value
8094 of c-font-lock-extra-types is ("\\sw+_t") which means fontification follows the
8095 convention that C type names end in _t. This results in slower fontification.
8096
8097 Of course, you can change the variables that specify fontification in whatever
8098 way you wish, typically by adding regexps. However, these new variables make
8099 it easier to make specific and common changes for the fontification of types.
8100
8101 *** Adding highlighting patterns to existing support
8102
8103 You can use the new function font-lock-add-keywords to add your own
8104 highlighting patterns, such as for project-local or user-specific constructs,
8105 for any mode.
8106
8107 For example, to highlight `FIXME:' words in C comments, put:
8108
8109 (font-lock-add-keywords 'c-mode '(("\\<FIXME:" 0 font-lock-warning-face t)))
8110
8111 in your ~/.emacs.
8112
8113 *** New faces
8114
8115 Font Lock now defines two new faces, font-lock-builtin-face and
8116 font-lock-warning-face. These are intended to highlight builtin keywords,
8117 distinct from a language's normal keywords, and objects that should be brought
8118 to user attention, respectively. Various modes now use these new faces.
8119
8120 *** Changes to fast-lock support mode
8121
8122 The fast-lock package, one of the two Font Lock support modes, can now process
8123 cache files silently. You can use the new variable fast-lock-verbose, in the
8124 same way as font-lock-verbose, to control this feature.
8125
8126 *** Changes to lazy-lock support mode
8127
8128 The lazy-lock package, one of the two Font Lock support modes, can now fontify
8129 according to the true syntactic context relative to other lines. You can use
8130 the new variable lazy-lock-defer-contextually to control this feature. If
8131 non-nil, changes to the buffer will cause subsequent lines in the buffer to be
8132 refontified after lazy-lock-defer-time seconds of idle time. If nil, then only
8133 the modified lines will be refontified; this is the same as the previous Lazy
8134 Lock mode behaviour and the behaviour of Font Lock mode.
8135
8136 This feature is useful in modes where strings or comments can span lines.
8137 For example, if a string or comment terminating character is deleted, then if
8138 this feature is enabled subsequent lines in the buffer will be correctly
8139 refontified to reflect their new syntactic context. Previously, only the line
8140 containing the deleted character would be refontified and you would have to use
8141 the command M-g M-g (font-lock-fontify-block) to refontify some lines.
8142
8143 As a consequence of this new feature, two other variables have changed:
8144
8145 Variable `lazy-lock-defer-driven' is renamed `lazy-lock-defer-on-scrolling'.
8146 Variable `lazy-lock-defer-time' can now only be a time, i.e., a number.
8147 Buffer modes for which on-the-fly deferral applies can be specified via the
8148 new variable `lazy-lock-defer-on-the-fly'.
8149
8150 If you set these variables in your ~/.emacs, then you may have to change those
8151 settings.
8152
8153 ** Ada mode changes.
8154
8155 *** There is now better support for using find-file.el with Ada mode.
8156 If you switch between spec and body, the cursor stays in the same
8157 procedure (modulo overloading). If a spec has no body file yet, but
8158 you try to switch to its body file, Ada mode now generates procedure
8159 stubs.
8160
8161 *** There are two new commands:
8162 - `ada-make-local' : invokes gnatmake on the current buffer
8163 - `ada-check-syntax' : check syntax of current buffer.
8164
8165 The user options `ada-compiler-make', `ada-make-options',
8166 `ada-language-version', `ada-compiler-syntax-check', and
8167 `ada-compile-options' are used within these commands.
8168
8169 *** Ada mode can now work with Outline minor mode. The outline level
8170 is calculated from the indenting, not from syntactic constructs.
8171 Outlining does not work if your code is not correctly indented.
8172
8173 *** The new function `ada-gnat-style' converts the buffer to the style of
8174 formatting used in GNAT. It places two blanks after a comment start,
8175 places one blank between a word end and an opening '(', and puts one
8176 space between a comma and the beginning of a word.
8177
8178 ** Scheme mode changes.
8179
8180 *** Scheme mode indentation now uses many of the facilities of Lisp
8181 mode; therefore, the variables to customize it are the variables used
8182 for Lisp mode which have names starting with `lisp-'. The variables
8183 with names starting with `scheme-' which used to do this no longer
8184 have any effect.
8185
8186 If you want to use different indentation for Scheme and Lisp, this is
8187 still possible, but now you must do it by adding a hook to
8188 scheme-mode-hook, which could work by setting the `lisp-' indentation
8189 variables as buffer-local variables.
8190
8191 *** DSSSL mode is a variant of Scheme mode, for editing DSSSL scripts.
8192 Use M-x dsssl-mode.
8193
8194 ** Changes to the emacsclient program
8195
8196 *** If a socket can't be found, and environment variables LOGNAME or
8197 USER are set, emacsclient now looks for a socket based on the UID
8198 associated with the name. That is an emacsclient running as root
8199 can connect to an Emacs server started by a non-root user.
8200
8201 *** The emacsclient program now accepts an option --no-wait which tells
8202 it to return immediately without waiting for you to "finish" the
8203 buffer in Emacs.
8204
8205 *** The new option --alternate-editor allows to specify an editor to
8206 use if Emacs is not running. The environment variable
8207 ALTERNATE_EDITOR can be used for the same effect; the command line
8208 option takes precedence.
8209
8210 ** M-x eldoc-mode enables a minor mode in which the echo area
8211 constantly shows the parameter list for function being called at point
8212 (in Emacs Lisp and Lisp Interaction modes only).
8213
8214 ** C-x n d now runs the new command narrow-to-defun,
8215 which narrows the accessible parts of the buffer to just
8216 the current defun.
8217
8218 ** Emacs now handles the `--' argument in the standard way; all
8219 following arguments are treated as ordinary file names.
8220
8221 ** On MSDOS and Windows, the bookmark file is now called _emacs.bmk,
8222 and the saved desktop file is now called _emacs.desktop (truncated if
8223 necessary).
8224
8225 ** When you kill a buffer that visits a file,
8226 if there are any registers that save positions in the file,
8227 these register values no longer become completely useless.
8228 If you try to go to such a register with C-x j, then you are
8229 asked whether to visit the file again. If you say yes,
8230 it visits the file and then goes to the same position.
8231
8232 ** When you visit a file that changes frequently outside Emacs--for
8233 example, a log of output from a process that continues to run--it may
8234 be useful for Emacs to revert the file without querying you whenever
8235 you visit the file afresh with C-x C-f.
8236
8237 You can request this behavior for certain files by setting the
8238 variable revert-without-query to a list of regular expressions. If a
8239 file's name matches any of these regular expressions, find-file and
8240 revert-buffer revert the buffer without asking for permission--but
8241 only if you have not edited the buffer text yourself.
8242
8243 ** set-default-font has been renamed to set-frame-font
8244 since it applies only to the current frame.
8245
8246 ** In TeX mode, you can use the variable tex-main-file to specify the
8247 file for tex-file to run TeX on. (By default, tex-main-file is nil,
8248 and tex-file runs TeX on the current visited file.)
8249
8250 This is useful when you are editing a document that consists of
8251 multiple files. In each of the included files, you can set up a local
8252 variable list which specifies the top-level file of your document for
8253 tex-main-file. Then tex-file will run TeX on the whole document
8254 instead of just the file you are editing.
8255
8256 ** RefTeX mode
8257
8258 RefTeX mode is a new minor mode with special support for \label, \ref
8259 and \cite macros in LaTeX documents. RefTeX distinguishes labels of
8260 different environments (equation, figure, ...) and has full support for
8261 multifile documents. To use it, select a buffer with a LaTeX document and
8262 turn the mode on with M-x reftex-mode. Here are the main user commands:
8263
8264 C-c ( reftex-label
8265 Creates a label semi-automatically. RefTeX is context sensitive and
8266 knows which kind of label is needed.
8267
8268 C-c ) reftex-reference
8269 Offers in a menu all labels in the document, along with context of the
8270 label definition. The selected label is referenced as \ref{LABEL}.
8271
8272 C-c [ reftex-citation
8273 Prompts for a regular expression and displays a list of matching BibTeX
8274 database entries. The selected entry is cited with a \cite{KEY} macro.
8275
8276 C-c & reftex-view-crossref
8277 Views the cross reference of a \ref or \cite command near point.
8278
8279 C-c = reftex-toc
8280 Shows a table of contents of the (multifile) document. From there you
8281 can quickly jump to every section.
8282
8283 Under X, RefTeX installs a "Ref" menu in the menu bar, with additional
8284 commands. Press `?' to get help when a prompt mentions this feature.
8285 Full documentation and customization examples are in the file
8286 reftex.el. You can use the finder to view the file documentation:
8287 C-h p --> tex --> reftex.el
8288
8289 ** Changes in BibTeX mode.
8290
8291 *** Info documentation is now available.
8292
8293 *** Don't allow parentheses in string constants anymore. This confused
8294 both the BibTeX program and Emacs BibTeX mode.
8295
8296 *** Renamed variable bibtex-mode-user-optional-fields to
8297 bibtex-user-optional-fields.
8298
8299 *** Removed variable bibtex-include-OPTannote
8300 (use bibtex-user-optional-fields instead).
8301
8302 *** New interactive functions to copy and kill fields and complete
8303 entries to the BibTeX kill ring, from where they can be yanked back by
8304 appropriate functions.
8305
8306 *** New interactive functions for repositioning and marking of
8307 entries. They are bound by default to C-M-l and C-M-h.
8308
8309 *** New hook bibtex-clean-entry-hook. It is called after entry has
8310 been cleaned.
8311
8312 *** New variable bibtex-field-delimiters, which replaces variables
8313 bibtex-field-{left|right}-delimiter.
8314
8315 *** New variable bibtex-entry-delimiters to determine how entries
8316 shall be delimited.
8317
8318 *** Allow preinitialization of fields. See documentation of
8319 bibtex-user-optional-fields, bibtex-entry-field-alist, and
8320 bibtex-include-OPTkey for details.
8321
8322 *** Book and InBook entries require either an author or an editor
8323 field. This is now supported by bibtex.el. Alternative fields are
8324 prefixed with `ALT'.
8325
8326 *** New variable bibtex-entry-format, which replaces variable
8327 bibtex-clean-entry-zap-empty-opts and allows specification of many
8328 formatting options performed on cleaning an entry (see variable
8329 documentation).
8330
8331 *** Even more control on how automatic keys are generated. See
8332 documentation of bibtex-generate-autokey for details. Transcriptions
8333 for foreign languages other than German are now handled, too.
8334
8335 *** New boolean user option bibtex-comma-after-last-field to decide if
8336 comma should be inserted at end of last field.
8337
8338 *** New boolean user option bibtex-align-at-equal-sign to determine if
8339 alignment should be made at left side of field contents or at equal
8340 signs. New user options to control entry layout (e.g. indentation).
8341
8342 *** New function bibtex-fill-entry to realign entries.
8343
8344 *** New function bibtex-reformat to reformat region or buffer.
8345
8346 *** New function bibtex-convert-alien to convert a BibTeX database
8347 from alien sources.
8348
8349 *** New function bibtex-complete-key (similar to bibtex-complete-string)
8350 to complete prefix to a key defined in buffer. Mainly useful in
8351 crossref entries.
8352
8353 *** New function bibtex-count-entries to count entries in buffer or
8354 region.
8355
8356 *** Added support for imenu.
8357
8358 *** The function `bibtex-validate' now checks current region instead
8359 of buffer if mark is active. Now it shows all errors of buffer in a
8360 `compilation mode' buffer. You can use the normal commands (e.g.
8361 `next-error') for compilation modes to jump to errors.
8362
8363 *** New variable `bibtex-string-file-path' to determine where the files
8364 from `bibtex-string-files' are searched.
8365
8366 ** Iso Accents mode now supports Latin-3 as an alternative.
8367
8368 ** The command next-error now opens blocks hidden by hideshow.
8369
8370 ** The function using-unix-filesystems has been replaced by the
8371 functions add-untranslated-filesystem and remove-untranslated-filesystem.
8372 Each of these functions takes the name of a drive letter or directory
8373 as an argument.
8374
8375 When a filesystem is added as untranslated, all files on it are read
8376 and written in binary mode (no cr/lf translation is performed).
8377
8378 ** browse-url changes
8379
8380 *** New methods for: Grail (browse-url-generic), MMM (browse-url-mmm),
8381 Lynx in a separate xterm (browse-url-lynx-xterm) or in an Emacs window
8382 (browse-url-lynx-emacs), remote W3 (browse-url-w3-gnudoit), generic
8383 non-remote-controlled browsers (browse-url-generic) and associated
8384 customization variables.
8385
8386 *** New commands `browse-url-of-region' and `browse-url'.
8387
8388 *** URLs marked up with <URL:...> (RFC1738) work if broken across
8389 lines. Browsing methods can be associated with URL regexps
8390 (e.g. mailto: URLs) via `browse-url-browser-function'.
8391
8392 ** Changes in Ediff
8393
8394 *** Clicking Mouse-2 on a brief command description in Ediff control panel
8395 pops up the Info file for this command.
8396
8397 *** There is now a variable, ediff-autostore-merges, which controls whether
8398 the result of a merge is saved in a file. By default, this is done only when
8399 merge is done from a session group (eg, when merging files in two different
8400 directories).
8401
8402 *** Since Emacs 19.31 (this hasn't been announced before), Ediff can compare
8403 and merge groups of files residing in different directories, or revisions of
8404 files in the same directory.
8405
8406 *** Since Emacs 19.31, Ediff can apply multi-file patches interactively.
8407 The patches must be in the context format or GNU unified format. (The bug
8408 related to the GNU format has now been fixed.)
8409
8410 ** Changes in Viper
8411
8412 *** The startup file is now .viper instead of .vip
8413 *** All variable/function names have been changed to start with viper-
8414 instead of vip-.
8415 *** C-\ now simulates the meta-key in all Viper states.
8416 *** C-z in Insert state now escapes to Vi for the duration of the next
8417 Viper command. In Vi and Insert states, C-z behaves as before.
8418 *** C-c \ escapes to Vi for one command if Viper is in Insert or Emacs states.
8419 *** _ is no longer the meta-key in Vi state.
8420 *** The variable viper-insert-state-cursor-color can be used to change cursor
8421 color when Viper is in insert state.
8422 *** If search lands the cursor near the top or the bottom of the window,
8423 Viper pulls the window up or down to expose more context. The variable
8424 viper-adjust-window-after-search controls this behavior.
8425
8426 ** Etags changes.
8427
8428 *** In C, C++, Objective C and Java, Etags tags global variables by
8429 default. The resulting tags files are inflated by 30% on average.
8430 Use --no-globals to turn this feature off. Etags can also tag
8431 variables which are members of structure-like constructs, but it does
8432 not by default. Use --members to turn this feature on.
8433
8434 *** C++ member functions are now recognized as tags.
8435
8436 *** Java is tagged like C++. In addition, "extends" and "implements"
8437 constructs are tagged. Files are recognised by the extension .java.
8438
8439 *** Etags can now handle programs written in Postscript. Files are
8440 recognised by the extensions .ps and .pdb (Postscript with C syntax).
8441 In Postscript, tags are lines that start with a slash.
8442
8443 *** Etags now handles Objective C and Objective C++ code. The usual C and
8444 C++ tags are recognized in these languages; in addition, etags
8445 recognizes special Objective C syntax for classes, class categories,
8446 methods and protocols.
8447
8448 *** Etags also handles Cobol. Files are recognised by the extension
8449 .cobol. The tagged lines are those containing a word that begins in
8450 column 8 and ends in a full stop, i.e. anything that could be a
8451 paragraph name.
8452
8453 *** Regexps in Etags now support intervals, as in ed or grep. The syntax of
8454 an interval is \{M,N\}, and it means to match the preceding expression
8455 at least M times and as many as N times.
8456
8457 ** The format for specifying a custom format for time-stamp to insert
8458 in files has changed slightly.
8459
8460 With the new enhancements to the functionality of format-time-string,
8461 time-stamp-format will change to be eventually compatible with it.
8462 This conversion is being done in two steps to maintain compatibility
8463 with old time-stamp-format values.
8464
8465 In the new scheme, alternate case is signified by the number-sign
8466 (`#') modifier, rather than changing the case of the format character.
8467 This feature is as yet incompletely implemented for compatibility
8468 reasons.
8469
8470 In the old time-stamp-format, all numeric fields defaulted to their
8471 natural width. (With format-time-string, each format has a
8472 fixed-width default.) In this version, you can specify the colon
8473 (`:') modifier to a numeric conversion to mean "give me the historical
8474 time-stamp-format width default." Do not use colon if you are
8475 specifying an explicit width, as in "%02d".
8476
8477 Numbers are no longer truncated to the requested width, except in the
8478 case of "%02y", which continues to give a two-digit year. Digit
8479 truncation probably wasn't being used for anything else anyway.
8480
8481 The new formats will work with old versions of Emacs. New formats are
8482 being recommended now to allow time-stamp-format to change in the
8483 future to be compatible with format-time-string. The new forms being
8484 recommended now will continue to work then.
8485
8486 See the documentation string for the variable time-stamp-format for
8487 details.
8488
8489 ** There are some additional major modes:
8490
8491 dcl-mode, for editing VMS DCL files.
8492 m4-mode, for editing files of m4 input.
8493 meta-mode, for editing MetaFont and MetaPost source files.
8494
8495 ** In Shell mode, the command shell-copy-environment-variable lets you
8496 copy the value of a specified environment variable from the subshell
8497 into Emacs.
8498
8499 ** New Lisp packages include:
8500
8501 *** battery.el displays battery status for laptops.
8502
8503 *** M-x bruce (named after Lenny Bruce) is a program that might
8504 be used for adding some indecent words to your email.
8505
8506 *** M-x crisp-mode enables an emulation for the CRiSP editor.
8507
8508 *** M-x dirtrack arranges for better tracking of directory changes
8509 in shell buffers.
8510
8511 *** The new library elint.el provides for linting of Emacs Lisp code.
8512 See the documentation for `elint-initialize', `elint-current-buffer'
8513 and `elint-defun'.
8514
8515 *** M-x expand-add-abbrevs defines a special kind of abbrev which is
8516 meant for programming constructs. These abbrevs expand like ordinary
8517 ones, when you type SPC, but only at the end of a line and not within
8518 strings or comments.
8519
8520 These abbrevs can act as templates: you can define places within an
8521 abbrev for insertion of additional text. Once you expand the abbrev,
8522 you can then use C-x a p and C-x a n to move back and forth to these
8523 insertion points. Thus you can conveniently insert additional text
8524 at these points.
8525
8526 *** filecache.el remembers the location of files so that you
8527 can visit them by short forms of their names.
8528
8529 *** find-func.el lets you find the definition of the user-loaded
8530 Emacs Lisp function at point.
8531
8532 *** M-x handwrite converts text to a "handwritten" picture.
8533
8534 *** M-x iswitchb-buffer is a command for switching to a buffer, much like
8535 switch-buffer, but it reads the argument in a more helpful way.
8536
8537 *** M-x landmark implements a neural network for landmark learning.
8538
8539 *** M-x locate provides a convenient interface to the `locate' program.
8540
8541 *** M4 mode is a new mode for editing files of m4 input.
8542
8543 *** mantemp.el creates C++ manual template instantiations
8544 from the GCC error messages which indicate which instantiations are needed.
8545
8546 *** mouse-copy.el provides a one-click copy and move feature.
8547 You can drag a region with M-mouse-1, and it is automatically
8548 inserted at point. M-Shift-mouse-1 deletes the text from its
8549 original place after inserting the copy.
8550
8551 *** mouse-drag.el lets you do scrolling by dragging Mouse-2
8552 on the buffer.
8553
8554 You click the mouse and move; that distance either translates into the
8555 velocity to scroll (with mouse-drag-throw) or the distance to scroll
8556 (with mouse-drag-drag). Horizontal scrolling is enabled when needed.
8557
8558 Enable mouse-drag with:
8559 (global-set-key [down-mouse-2] 'mouse-drag-throw)
8560 -or-
8561 (global-set-key [down-mouse-2] 'mouse-drag-drag)
8562
8563 *** mspools.el is useful for determining which mail folders have
8564 mail waiting to be read in them. It works with procmail.
8565
8566 *** Octave mode is a major mode for editing files of input for Octave.
8567 It comes with a facility for communicating with an Octave subprocess.
8568
8569 *** ogonek
8570
8571 The ogonek package provides functions for changing the coding of
8572 Polish diacritic characters in buffers. Codings known from various
8573 platforms are supported such as ISO8859-2, Mazovia, IBM Latin2, and
8574 TeX. For example, you can change the coding from Mazovia to
8575 ISO8859-2. Another example is a change of coding from ISO8859-2 to
8576 prefix notation (in which `/a' stands for the aogonek character, for
8577 instance) and vice versa.
8578
8579 To use this package load it using
8580 M-x load-library [enter] ogonek
8581 Then, you may get an explanation by calling one of
8582 M-x ogonek-jak -- in Polish
8583 M-x ogonek-how -- in English
8584 The info specifies the commands and variables provided as well as the
8585 ways of customization in `.emacs'.
8586
8587 *** Interface to ph.
8588
8589 Emacs provides a client interface to CCSO Nameservers (ph/qi)
8590
8591 The CCSO nameserver is used in many universities to provide directory
8592 services about people. ph.el provides a convenient Emacs interface to
8593 these servers.
8594
8595 *** uce.el is useful for replying to unsolicited commercial email.
8596
8597 *** vcursor.el implements a "virtual cursor" feature.
8598 You can move the virtual cursor with special commands
8599 while the real cursor does not move.
8600
8601 *** webjump.el is a "hot list" package which you can set up
8602 for visiting your favorite web sites.
8603
8604 *** M-x winner-mode is a minor mode which saves window configurations,
8605 so you can move back to other configurations that you have recently used.
8606
8607 ** movemail change
8608
8609 Movemail no longer needs to be installed setuid root in order for POP
8610 mail retrieval to function properly. This is because it no longer
8611 supports the RPOP (reserved-port POP) protocol; instead, it uses the
8612 user's POP password to authenticate to the mail server.
8613
8614 This change was made earlier, but not reported in NEWS before.
8615 \f
8616 * Emacs 20.1 changes for MS-DOS and MS-Windows.
8617
8618 ** Changes in handling MS-DOS/MS-Windows text files.
8619
8620 Emacs handles three different conventions for representing
8621 end-of-line: CRLF for MSDOS, LF for Unix and GNU, and CR (used on the
8622 Macintosh). Emacs determines which convention is used in a specific
8623 file based on the contents of that file (except for certain special
8624 file names), and when it saves the file, it uses the same convention.
8625
8626 To save the file and change the end-of-line convention, you can use
8627 C-x RET f (set-buffer-file-coding-system) to specify a different
8628 coding system for the buffer. Then, when you save the file, the newly
8629 specified coding system will take effect. For example, to save with
8630 LF, specify undecided-unix (or some other ...-unix coding system); to
8631 save with CRLF, specify undecided-dos.
8632 \f
8633 * Lisp Changes in Emacs 20.1
8634
8635 ** Byte-compiled files made with Emacs 20 will, in general, work in
8636 Emacs 19 as well, as long as the source code runs in Emacs 19. And
8637 vice versa: byte-compiled files made with Emacs 19 should also run in
8638 Emacs 20, as long as the program itself works in Emacs 20.
8639
8640 ** Windows-specific functions and variables have been renamed
8641 to start with w32- instead of win32-.
8642
8643 In hacker language, calling something a "win" is a form of praise. We
8644 don't want to praise a non-free Microsoft system, so we don't call it
8645 "win".
8646
8647 ** Basic Lisp changes
8648
8649 *** A symbol whose name starts with a colon now automatically
8650 evaluates to itself. Therefore such a symbol can be used as a constant.
8651
8652 *** The defined purpose of `defconst' has been changed. It should now
8653 be used only for values that should not be changed whether by a program
8654 or by the user.
8655
8656 The actual behavior of defconst has not been changed.
8657
8658 *** There are new macros `when' and `unless'
8659
8660 (when CONDITION BODY...) is short for (if CONDITION (progn BODY...))
8661 (unless CONDITION BODY...) is short for (if CONDITION nil BODY...)
8662
8663 *** Emacs now defines functions caar, cadr, cdar and cddr with their
8664 usual Lisp meanings. For example, caar returns the car of the car of
8665 its argument.
8666
8667 *** equal, when comparing strings, now ignores their text properties.
8668
8669 *** The new function `functionp' tests whether an object is a function.
8670
8671 *** arrayp now returns t for char-tables and bool-vectors.
8672
8673 *** Certain primitives which use characters (as integers) now get an
8674 error if the integer is not a valid character code. These primitives
8675 include insert-char, char-to-string, and the %c construct in the
8676 `format' function.
8677
8678 *** The `require' function now insists on adding a suffix, either .el
8679 or .elc, to the file name. Thus, (require 'foo) will not use a file
8680 whose name is just foo. It insists on foo.el or foo.elc.
8681
8682 *** The `autoload' function, when the file name does not contain
8683 either a directory name or the suffix .el or .elc, insists on
8684 adding one of these suffixes.
8685
8686 *** string-to-number now takes an optional second argument BASE
8687 which specifies the base to use when converting an integer.
8688 If BASE is omitted, base 10 is used.
8689
8690 We have not implemented other radices for floating point numbers,
8691 because that would be much more work and does not seem useful.
8692
8693 *** substring now handles vectors as well as strings.
8694
8695 *** The Common Lisp function eql is no longer defined normally.
8696 You must load the `cl' library to define it.
8697
8698 *** The new macro `with-current-buffer' lets you evaluate an expression
8699 conveniently with a different current buffer. It looks like this:
8700
8701 (with-current-buffer BUFFER BODY-FORMS...)
8702
8703 BUFFER is the expression that says which buffer to use.
8704 BODY-FORMS say what to do in that buffer.
8705
8706 *** The new primitive `save-current-buffer' saves and restores the
8707 choice of current buffer, like `save-excursion', but without saving or
8708 restoring the value of point or the mark. `with-current-buffer'
8709 works using `save-current-buffer'.
8710
8711 *** The new macro `with-temp-file' lets you do some work in a new buffer and
8712 write the output to a specified file. Like `progn', it returns the value
8713 of the last form.
8714
8715 *** The new macro `with-temp-buffer' lets you do some work in a new buffer,
8716 which is discarded after use. Like `progn', it returns the value of the
8717 last form. If you wish to return the buffer contents, use (buffer-string)
8718 as the last form.
8719
8720 *** The new function split-string takes a string, splits it at certain
8721 characters, and returns a list of the substrings in between the
8722 matches.
8723
8724 For example, (split-string "foo bar lose" " +") returns ("foo" "bar" "lose").
8725
8726 *** The new macro with-output-to-string executes some Lisp expressions
8727 with standard-output set up so that all output feeds into a string.
8728 Then it returns that string.
8729
8730 For example, if the current buffer name is `foo',
8731
8732 (with-output-to-string
8733 (princ "The buffer is ")
8734 (princ (buffer-name)))
8735
8736 returns "The buffer is foo".
8737
8738 ** Non-ASCII characters are now supported, if enable-multibyte-characters
8739 is non-nil.
8740
8741 These characters have character codes above 256. When inserted in the
8742 buffer or stored in a string, they are represented as multibyte
8743 characters that occupy several buffer positions each.
8744
8745 *** When enable-multibyte-characters is non-nil, a single character in
8746 a buffer or string can be two or more bytes (as many as four).
8747
8748 Buffers and strings are still made up of unibyte elements;
8749 character positions and string indices are always measured in bytes.
8750 Therefore, moving forward one character can increase the buffer
8751 position by 2, 3 or 4. The function forward-char moves by whole
8752 characters, and therefore is no longer equivalent to
8753 (lambda (n) (goto-char (+ (point) n))).
8754
8755 ASCII characters (codes 0 through 127) are still single bytes, always.
8756 Sequences of byte values 128 through 255 are used to represent
8757 non-ASCII characters. These sequences are called "multibyte
8758 characters".
8759
8760 The first byte of a multibyte character is always in the range 128
8761 through 159 (octal 0200 through 0237). These values are called
8762 "leading codes". The second and subsequent bytes are always in the
8763 range 160 through 255 (octal 0240 through 0377). The first byte, the
8764 leading code, determines how many bytes long the sequence is.
8765
8766 *** The function forward-char moves over characters, and therefore
8767 (forward-char 1) may increase point by more than 1 if it moves over a
8768 multibyte character. Likewise, delete-char always deletes a
8769 character, which may be more than one buffer position.
8770
8771 This means that some Lisp programs, which assume that a character is
8772 always one buffer position, need to be changed.
8773
8774 However, all ASCII characters are always one buffer position.
8775
8776 *** The regexp [\200-\377] no longer matches all non-ASCII characters,
8777 because when enable-multibyte-characters is non-nil, these characters
8778 have codes that are not in the range octal 200 to octal 377. However,
8779 the regexp [^\000-\177] does match all non-ASCII characters,
8780 guaranteed.
8781
8782 *** The function char-boundary-p returns non-nil if position POS is
8783 between two characters in the buffer (not in the middle of a
8784 character).
8785
8786 When the value is non-nil, it says what kind of character follows POS:
8787
8788 0 if POS is at an ASCII character or at the end of range,
8789 1 if POS is before a 2-byte length multi-byte form,
8790 2 if POS is at a head of 3-byte length multi-byte form,
8791 3 if POS is at a head of 4-byte length multi-byte form,
8792 4 if POS is at a head of multi-byte form of a composite character.
8793
8794 *** The function char-bytes returns how many bytes the character CHAR uses.
8795
8796 *** Strings can contain multibyte characters. The function
8797 `length' returns the string length counting bytes, which may be
8798 more than the number of characters.
8799
8800 You can include a multibyte character in a string constant by writing
8801 it literally. You can also represent it with a hex escape,
8802 \xNNNNNNN..., using as many digits as necessary. Any character which
8803 is not a valid hex digit terminates this construct. If you want to
8804 follow it with a character that is a hex digit, write backslash and
8805 newline in between; that will terminate the hex escape.
8806
8807 *** The function concat-chars takes arguments which are characters
8808 and returns a string containing those characters.
8809
8810 *** The function sref access a multibyte character in a string.
8811 (sref STRING INDX) returns the character in STRING at INDEX. INDEX
8812 counts from zero. If INDEX is at a position in the middle of a
8813 character, sref signals an error.
8814
8815 *** The function chars-in-string returns the number of characters
8816 in a string. This is less than the length of the string, if the
8817 string contains multibyte characters (the length counts bytes).
8818
8819 *** The function chars-in-region returns the number of characters
8820 in a region from BEG to END. This is less than (- END BEG) if the
8821 region contains multibyte characters (the length counts bytes).
8822
8823 *** The function string-to-list converts a string to a list of
8824 the characters in it. string-to-vector converts a string
8825 to a vector of the characters in it.
8826
8827 *** The function store-substring alters part of the contents
8828 of a string. You call it as follows:
8829
8830 (store-substring STRING IDX OBJ)
8831
8832 This says to alter STRING, by storing OBJ starting at index IDX in
8833 STRING. OBJ may be either a character or a (smaller) string.
8834 This function really does alter the contents of STRING.
8835 Since it is impossible to change the length of an existing string,
8836 it is an error if OBJ doesn't fit within STRING's actual length.
8837
8838 *** char-width returns the width (in columns) of the character CHAR,
8839 if it were displayed in the current buffer and the selected window.
8840
8841 *** string-width returns the width (in columns) of the text in STRING,
8842 if it were displayed in the current buffer and the selected window.
8843
8844 *** truncate-string-to-width shortens a string, if necessary,
8845 to fit within a certain number of columns. (Of course, it does
8846 not alter the string that you give it; it returns a new string
8847 which contains all or just part of the existing string.)
8848
8849 (truncate-string-to-width STR END-COLUMN &optional START-COLUMN PADDING)
8850
8851 This returns the part of STR up to column END-COLUMN.
8852
8853 The optional argument START-COLUMN specifies the starting column.
8854 If this is non-nil, then the first START-COLUMN columns of the string
8855 are not included in the resulting value.
8856
8857 The optional argument PADDING, if non-nil, is a padding character to be added
8858 at the beginning and end the resulting string, to extend it to exactly
8859 WIDTH columns. If PADDING is nil, that means do not pad; then, if STRING
8860 is narrower than WIDTH, the value is equal to STRING.
8861
8862 If PADDING and START-COLUMN are both non-nil, and if there is no clean
8863 place in STRING that corresponds to START-COLUMN (because one
8864 character extends across that column), then the padding character
8865 PADDING is added one or more times at the beginning of the result
8866 string, so that its columns line up as if it really did start at
8867 column START-COLUMN.
8868
8869 *** When the functions in the list after-change-functions are called,
8870 the third argument is the number of bytes in the pre-change text, not
8871 necessarily the number of characters. It is, in effect, the
8872 difference in buffer position between the beginning and the end of the
8873 changed text, before the change.
8874
8875 *** The characters Emacs uses are classified in various character
8876 sets, each of which has a name which is a symbol. In general there is
8877 one character set for each script, not for each language.
8878
8879 **** The function charsetp tests whether an object is a character set name.
8880
8881 **** The variable charset-list holds a list of character set names.
8882
8883 **** char-charset, given a character code, returns the name of the character
8884 set that the character belongs to. (The value is a symbol.)
8885
8886 **** split-char, given a character code, returns a list containing the
8887 name of the character set, followed by one or two byte-values
8888 which identify the character within that character set.
8889
8890 **** make-char, given a character set name and one or two subsequent
8891 byte-values, constructs a character code. This is roughly the
8892 opposite of split-char.
8893
8894 **** find-charset-region returns a list of the character sets
8895 of all the characters between BEG and END.
8896
8897 **** find-charset-string returns a list of the character sets
8898 of all the characters in a string.
8899
8900 *** Here are the Lisp facilities for working with coding systems
8901 and specifying coding systems.
8902
8903 **** The function coding-system-list returns a list of all coding
8904 system names (symbols). With optional argument t, it returns a list
8905 of all distinct base coding systems, not including variants.
8906 (Variant coding systems are those like latin-1-dos, latin-1-unix
8907 and latin-1-mac which specify the end-of-line conversion as well
8908 as what to do about code conversion.)
8909
8910 **** coding-system-p tests a symbol to see if it is a coding system
8911 name. It returns t if so, nil if not.
8912
8913 **** file-coding-system-alist specifies which coding systems to use
8914 for certain file names. It works like network-coding-system-alist,
8915 except that the PATTERN is matched against the file name.
8916
8917 Each element has the format (PATTERN . VAL), where PATTERN determines
8918 which file names the element applies to. PATTERN should be a regexp
8919 to match against a file name.
8920
8921 VAL is a coding system, a cons cell containing two coding systems, or
8922 a function symbol. If VAL is a coding system, it is used for both
8923 decoding what received from the network stream and encoding what sent
8924 to the network stream. If VAL is a cons cell containing two coding
8925 systems, the car specifies the coding system for decoding, and the cdr
8926 specifies the coding system for encoding.
8927
8928 If VAL is a function symbol, the function must return a coding system
8929 or a cons cell containing two coding systems, which is used as above.
8930
8931 **** The variable network-coding-system-alist specifies
8932 the coding system to use for network sockets.
8933
8934 Each element has the format (PATTERN . VAL), where PATTERN determines
8935 which network sockets the element applies to. PATTERN should be
8936 either a port number or a regular expression matching some network
8937 service names.
8938
8939 VAL is a coding system, a cons cell containing two coding systems, or
8940 a function symbol. If VAL is a coding system, it is used for both
8941 decoding what received from the network stream and encoding what sent
8942 to the network stream. If VAL is a cons cell containing two coding
8943 systems, the car specifies the coding system for decoding, and the cdr
8944 specifies the coding system for encoding.
8945
8946 If VAL is a function symbol, the function must return a coding system
8947 or a cons cell containing two coding systems, which is used as above.
8948
8949 **** process-coding-system-alist specifies which coding systems to use
8950 for certain subprocess. It works like network-coding-system-alist,
8951 except that the PATTERN is matched against the program name used to
8952 start the subprocess.
8953
8954 **** The variable default-process-coding-system specifies the coding
8955 systems to use for subprocess (and net connection) input and output,
8956 when nothing else specifies what to do. The value is a cons cell
8957 (OUTPUT-CODING . INPUT-CODING). OUTPUT-CODING applies to output
8958 to the subprocess, and INPUT-CODING applies to input from it.
8959
8960 **** The variable coding-system-for-write, if non-nil, specifies the
8961 coding system to use for writing a file, or for output to a synchronous
8962 subprocess.
8963
8964 It also applies to any asynchronous subprocess or network connection,
8965 but in a different way: the value of coding-system-for-write when you
8966 start the subprocess or connection affects that subprocess or
8967 connection permanently or until overridden.
8968
8969 The variable coding-system-for-write takes precedence over
8970 file-coding-system-alist, process-coding-system-alist and
8971 network-coding-system-alist, and all other methods of specifying a
8972 coding system for output. But most of the time this variable is nil.
8973 It exists so that Lisp programs can bind it to a specific coding
8974 system for one operation at a time.
8975
8976 **** coding-system-for-read applies similarly to input from
8977 files, subprocesses or network connections.
8978
8979 **** The function process-coding-system tells you what
8980 coding systems(s) an existing subprocess is using.
8981 The value is a cons cell,
8982 (DECODING-CODING-SYSTEM . ENCODING-CODING-SYSTEM)
8983 where DECODING-CODING-SYSTEM is used for decoding output from
8984 the subprocess, and ENCODING-CODING-SYSTEM is used for encoding
8985 input to the subprocess.
8986
8987 **** The function set-process-coding-system can be used to
8988 change the coding systems in use for an existing subprocess.
8989
8990 ** Emacs has a new facility to help users manage the many
8991 customization options. To make a Lisp program work with this facility,
8992 you need to use the new macros defgroup and defcustom.
8993
8994 You use defcustom instead of defvar, for defining a user option
8995 variable. The difference is that you specify two additional pieces of
8996 information (usually): the "type" which says what values are
8997 legitimate, and the "group" which specifies the hierarchy for
8998 customization.
8999
9000 Thus, instead of writing
9001
9002 (defvar foo-blurgoze nil
9003 "*Non-nil means that foo will act very blurgozely.")
9004
9005 you would now write this:
9006
9007 (defcustom foo-blurgoze nil
9008 "*Non-nil means that foo will act very blurgozely."
9009 :type 'boolean
9010 :group foo)
9011
9012 The type `boolean' means that this variable has only
9013 two meaningful states: nil and non-nil. Other type values
9014 describe other possibilities; see the manual for Custom
9015 for a description of them.
9016
9017 The "group" argument is used to specify a group which the option
9018 should belong to. You define a new group like this:
9019
9020 (defgroup ispell nil
9021 "Spell checking using Ispell."
9022 :group 'processes)
9023
9024 The "group" argument in defgroup specifies the parent group. The root
9025 group is called `emacs'; it should not contain any variables itself,
9026 but only other groups. The immediate subgroups of `emacs' correspond
9027 to the keywords used by C-h p. Under these subgroups come
9028 second-level subgroups that belong to individual packages.
9029
9030 Each Emacs package should have its own set of groups. A simple
9031 package should have just one group; a more complex package should
9032 have a hierarchy of its own groups. The sole or root group of a
9033 package should be a subgroup of one or more of the "keyword"
9034 first-level subgroups.
9035
9036 ** New `widget' library for inserting UI components in buffers.
9037
9038 This library, used by the new custom library, is documented in a
9039 separate manual that accompanies Emacs.
9040
9041 ** easy-mmode
9042
9043 The easy-mmode package provides macros and functions that make
9044 developing minor modes easier. Roughly, the programmer has to code
9045 only the functionality of the minor mode. All the rest--toggles,
9046 predicate, and documentation--can be done in one call to the macro
9047 `easy-mmode-define-minor-mode' (see the documentation). See also
9048 `easy-mmode-define-keymap'.
9049
9050 ** Text property changes
9051
9052 *** The `intangible' property now works on overlays as well as on a
9053 text property.
9054
9055 *** The new functions next-char-property-change and
9056 previous-char-property-change scan through the buffer looking for a
9057 place where either a text property or an overlay might change. The
9058 functions take two arguments, POSITION and LIMIT. POSITION is the
9059 starting position for the scan. LIMIT says where to stop the scan.
9060
9061 If no property change is found before LIMIT, the value is LIMIT. If
9062 LIMIT is nil, scan goes to the beginning or end of the accessible part
9063 of the buffer. If no property change is found, the value is the
9064 position of the beginning or end of the buffer.
9065
9066 *** In the `local-map' text property or overlay property, the property
9067 value can now be a symbol whose function definition is a keymap. This
9068 is an alternative to using the keymap itself.
9069
9070 ** Changes in invisibility features
9071
9072 *** Isearch can now temporarily show parts of the buffer which are
9073 hidden by an overlay with a invisible property, when the search match
9074 is inside that portion of the buffer. To enable this the overlay
9075 should have a isearch-open-invisible property which is a function that
9076 would be called having the overlay as an argument, the function should
9077 make the overlay visible.
9078
9079 During incremental search the overlays are shown by modifying the
9080 invisible and intangible properties, if beside this more actions are
9081 needed the overlay should have a isearch-open-invisible-temporary
9082 which is a function. The function is called with 2 arguments: one is
9083 the overlay and the second is nil when it should show the overlay and
9084 t when it should hide it.
9085
9086 *** add-to-invisibility-spec, remove-from-invisibility-spec
9087
9088 Modes that use overlays to hide portions of a buffer should set the
9089 invisible property of the overlay to the mode's name (or another symbol)
9090 and modify the `buffer-invisibility-spec' to include that symbol.
9091 Use `add-to-invisibility-spec' and `remove-from-invisibility-spec' to
9092 manipulate the `buffer-invisibility-spec'.
9093 Here is an example of how to do this:
9094
9095 ;; If we want to display an ellipsis:
9096 (add-to-invisibility-spec '(my-symbol . t))
9097 ;; If you don't want ellipsis:
9098 (add-to-invisibility-spec 'my-symbol)
9099
9100 ...
9101 (overlay-put (make-overlay beginning end) 'invisible 'my-symbol)
9102
9103 ...
9104 ;; When done with the overlays:
9105 (remove-from-invisibility-spec '(my-symbol . t))
9106 ;; Or respectively:
9107 (remove-from-invisibility-spec 'my-symbol)
9108
9109 ** Changes in syntax parsing.
9110
9111 *** The syntax-directed buffer-scan functions (such as
9112 `parse-partial-sexp', `forward-word' and similar functions) can now
9113 obey syntax information specified by text properties, if the variable
9114 `parse-sexp-lookup-properties' is non-nil.
9115
9116 If the value of `parse-sexp-lookup-properties' is nil, the behavior
9117 is as before: the syntax-table of the current buffer is always
9118 used to determine the syntax of the character at the position.
9119
9120 When `parse-sexp-lookup-properties' is non-nil, the syntax of a
9121 character in the buffer is calculated thus:
9122
9123 a) if the `syntax-table' text-property of that character
9124 is a cons, this cons becomes the syntax-type;
9125
9126 Valid values of `syntax-table' text-property are: nil, a valid
9127 syntax-table, and a valid syntax-table element, i.e.,
9128 a cons cell of the form (SYNTAX-CODE . MATCHING-CHAR).
9129
9130 b) if the character's `syntax-table' text-property
9131 is a syntax table, this syntax table is used
9132 (instead of the syntax-table of the current buffer) to
9133 determine the syntax type of the character.
9134
9135 c) otherwise the syntax-type is determined by the syntax-table
9136 of the current buffer.
9137
9138 *** The meaning of \s in regular expressions is also affected by the
9139 value of `parse-sexp-lookup-properties'. The details are the same as
9140 for the syntax-directed buffer-scan functions.
9141
9142 *** There are two new syntax-codes, `!' and `|' (numeric values 14
9143 and 15). A character with a code `!' starts a comment which is ended
9144 only by another character with the same code (unless quoted). A
9145 character with a code `|' starts a string which is ended only by
9146 another character with the same code (unless quoted).
9147
9148 These codes are mainly meant for use as values of the `syntax-table'
9149 text property.
9150
9151 *** The function `parse-partial-sexp' has new semantics for the sixth
9152 arg COMMENTSTOP. If it is `syntax-table', parse stops after the start
9153 of a comment or a string, or after end of a comment or a string.
9154
9155 *** The state-list which the return value from `parse-partial-sexp'
9156 (and can also be used as an argument) now has an optional ninth
9157 element: the character address of the start of last comment or string;
9158 nil if none. The fourth and eighth elements have special values if the
9159 string/comment is started by a "!" or "|" syntax-code.
9160
9161 *** Since new features of `parse-partial-sexp' allow a complete
9162 syntactic parsing, `font-lock' no longer supports
9163 `font-lock-comment-start-regexp'.
9164
9165 ** Changes in face features
9166
9167 *** The face functions are now unconditionally defined in Emacs, even
9168 if it does not support displaying on a device that supports faces.
9169
9170 *** The function face-documentation returns the documentation string
9171 of a face (or nil if it doesn't have one).
9172
9173 *** The function face-bold-p returns t if a face should be bold.
9174 set-face-bold-p sets that flag.
9175
9176 *** The function face-italic-p returns t if a face should be italic.
9177 set-face-italic-p sets that flag.
9178
9179 *** You can now specify foreground and background colors for text
9180 by adding elements of the form (foreground-color . COLOR-NAME)
9181 and (background-color . COLOR-NAME) to the list of faces in
9182 the `face' property (either the character's text property or an
9183 overlay property).
9184
9185 This means that you no longer need to create named faces to use
9186 arbitrary colors in a Lisp package.
9187
9188 ** Changes in file-handling functions
9189
9190 *** File-access primitive functions no longer discard an extra redundant
9191 directory name from the beginning of the file name. In other words,
9192 they no longer do anything special with // or /~. That conversion
9193 is now done only in substitute-in-file-name.
9194
9195 This makes it possible for a Lisp program to open a file whose name
9196 begins with ~.
9197
9198 *** If copy-file is unable to set the date of the output file,
9199 it now signals an error with the condition file-date-error.
9200
9201 *** The inode number returned by file-attributes may be an integer (if
9202 the number fits in a Lisp integer) or a list of integers.
9203
9204 *** insert-file-contents can now read from a special file,
9205 as long as the arguments VISIT and REPLACE are nil.
9206
9207 *** The RAWFILE arg to find-file-noselect, if non-nil, now suppresses
9208 character code conversion as well as other things.
9209
9210 Meanwhile, this feature does work with remote file names
9211 (formerly it did not).
9212
9213 *** Lisp packages which create temporary files should use the TMPDIR
9214 environment variable to decide which directory to put them in.
9215
9216 *** interpreter-mode-alist elements now specify regexps
9217 instead of constant strings.
9218
9219 *** expand-file-name no longer treats `//' or `/~' specially. It used
9220 to delete all the text of a file name up through the first slash of
9221 any `//' or `/~' sequence. Now it passes them straight through.
9222
9223 substitute-in-file-name continues to treat those sequences specially,
9224 in the same way as before.
9225
9226 *** The variable `format-alist' is more general now.
9227 The FROM-FN and TO-FN in a format definition can now be strings
9228 which specify shell commands to use as filters to perform conversion.
9229
9230 *** The new function access-file tries to open a file, and signals an
9231 error if that fails. If the open succeeds, access-file does nothing
9232 else, and returns nil.
9233
9234 *** The function insert-directory now signals an error if the specified
9235 directory cannot be listed.
9236
9237 ** Changes in minibuffer input
9238
9239 *** The functions read-buffer, read-variable, read-command, read-string
9240 read-file-name, read-from-minibuffer and completing-read now take an
9241 additional argument which specifies the default value. If this
9242 argument is non-nil, it should be a string; that string is used in two
9243 ways:
9244
9245 It is returned if the user enters empty input.
9246 It is available through the history command M-n.
9247
9248 *** The functions read-string, read-from-minibuffer,
9249 read-no-blanks-input and completing-read now take an additional
9250 argument INHERIT-INPUT-METHOD. If this is non-nil, then the
9251 minibuffer inherits the current input method and the setting of
9252 enable-multibyte-characters from the previously current buffer.
9253
9254 In an interactive spec, you can use M instead of s to read an
9255 argument in this way.
9256
9257 *** All minibuffer input functions discard text properties
9258 from the text you enter in the minibuffer, unless the variable
9259 minibuffer-allow-text-properties is non-nil.
9260
9261 ** Echo area features
9262
9263 *** Clearing the echo area now runs the normal hook
9264 echo-area-clear-hook. Note that the echo area can be used while the
9265 minibuffer is active; in that case, the minibuffer is still active
9266 after the echo area is cleared.
9267
9268 *** The function current-message returns the message currently displayed
9269 in the echo area, or nil if there is none.
9270
9271 ** Keyboard input features
9272
9273 *** tty-erase-char is a new variable that reports which character was
9274 set up as the terminal's erase character when time Emacs was started.
9275
9276 *** num-nonmacro-input-events is the total number of input events
9277 received so far from the terminal. It does not count those generated
9278 by keyboard macros.
9279
9280 ** Frame-related changes
9281
9282 *** make-frame runs the normal hook before-make-frame-hook just before
9283 creating a frame, and just after creating a frame it runs the abnormal
9284 hook after-make-frame-functions with the new frame as arg.
9285
9286 *** The new hook window-configuration-change-hook is now run every time
9287 the window configuration has changed. The frame whose configuration
9288 has changed is the selected frame when the hook is run.
9289
9290 *** Each frame now independently records the order for recently
9291 selected buffers, in its buffer-list frame parameter, so that the
9292 value of other-buffer is now based on the buffers recently displayed
9293 in the selected frame.
9294
9295 *** The value of the frame parameter vertical-scroll-bars
9296 is now `left', `right' or nil. A non-nil value specifies
9297 which side of the window to put the scroll bars on.
9298
9299 ** X Windows features
9300
9301 *** You can examine X resources for other applications by binding
9302 x-resource-class around a call to x-get-resource. The usual value of
9303 x-resource-class is "Emacs", which is the correct value for Emacs.
9304
9305 *** In menus, checkboxes and radio buttons now actually work.
9306 The menu displays the current status of the box or button.
9307
9308 *** The function x-list-fonts now takes an optional fourth argument
9309 MAXIMUM which sets a limit on how many matching fonts to return.
9310 A smaller value of MAXIMUM makes the function faster.
9311
9312 If the only question is whether *any* font matches the pattern,
9313 it is good to supply 1 for this argument.
9314
9315 ** Subprocess features
9316
9317 *** A reminder: it is no longer necessary for subprocess filter
9318 functions and sentinels to do save-match-data, because Emacs does this
9319 automatically.
9320
9321 *** The new function shell-command-to-string executes a shell command
9322 and returns the output from the command as a string.
9323
9324 *** The new function process-contact returns t for a child process,
9325 and (HOSTNAME SERVICE) for a net connection.
9326
9327 ** An error in running pre-command-hook or post-command-hook
9328 does clear the variable to nil. The documentation was wrong before.
9329
9330 ** In define-key-after, if AFTER is t, the new binding now always goes
9331 at the end of the keymap. If the keymap is a menu, this means it
9332 goes after the other menu items.
9333
9334 ** If you have a program that makes several changes in the same area
9335 of the buffer, you can use the macro combine-after-change-calls
9336 around that Lisp code to make it faster when after-change hooks
9337 are in use.
9338
9339 The macro arranges to call the after-change functions just once for a
9340 series of several changes--if that seems safe.
9341
9342 Don't alter the variables after-change-functions and
9343 after-change-function within the body of a combine-after-change-calls
9344 form.
9345
9346 ** If you define an abbrev (with define-abbrev) whose EXPANSION
9347 is not a string, then the abbrev does not expand in the usual sense,
9348 but its hook is still run.
9349
9350 ** Normally, the Lisp debugger is not used (even if you have enabled it)
9351 for errors that are handled by condition-case.
9352
9353 If you set debug-on-signal to a non-nil value, then the debugger is called
9354 regardless of whether there is a handler for the condition. This is
9355 useful for debugging problems that happen inside of a condition-case.
9356
9357 This mode of operation seems to be unreliable in other ways. Errors that
9358 are normal and ought to be handled, perhaps in timers or process
9359 filters, will instead invoke the debugger. So don't say you weren't
9360 warned.
9361
9362 ** The new variable ring-bell-function lets you specify your own
9363 way for Emacs to "ring the bell".
9364
9365 ** If run-at-time's TIME argument is t, the action is repeated at
9366 integral multiples of REPEAT from the epoch; this is useful for
9367 functions like display-time.
9368
9369 ** You can use the function locate-library to find the precise file
9370 name of a Lisp library. This isn't new, but wasn't documented before.
9371
9372 ** Commands for entering view mode have new optional arguments that
9373 can be used from Lisp. Low-level entrance to and exit from view mode
9374 is done by functions view-mode-enter and view-mode-exit.
9375
9376 ** batch-byte-compile-file now makes Emacs return a nonzero status code
9377 if there is an error in compilation.
9378
9379 ** pop-to-buffer, switch-to-buffer-other-window and
9380 switch-to-buffer-other-frame now accept an additional optional
9381 argument NORECORD, much like switch-to-buffer. If it is non-nil,
9382 they don't put the buffer at the front of the buffer list.
9383
9384 ** If your .emacs file leaves the *scratch* buffer non-empty,
9385 Emacs does not display the startup message, so as to avoid changing
9386 the *scratch* buffer.
9387
9388 ** The new function regexp-opt returns an efficient regexp to match a string.
9389 The arguments are STRINGS and (optionally) PAREN. This function can be used
9390 where regexp matching or searching is intensively used and speed is important,
9391 e.g., in Font Lock mode.
9392
9393 ** The variable buffer-display-count is local to each buffer,
9394 and is incremented each time the buffer is displayed in a window.
9395 It starts at 0 when the buffer is created.
9396
9397 ** The new function compose-mail starts composing a mail message
9398 using the user's chosen mail composition agent (specified with the
9399 variable mail-user-agent). It has variants compose-mail-other-window
9400 and compose-mail-other-frame.
9401
9402 ** The `user-full-name' function now takes an optional parameter which
9403 can either be a number (the UID) or a string (the login name). The
9404 full name of the specified user will be returned.
9405
9406 ** Lisp packages that load files of customizations, or any other sort
9407 of user profile, should obey the variable init-file-user in deciding
9408 where to find it. They should load the profile of the user name found
9409 in that variable. If init-file-user is nil, meaning that the -q
9410 option was used, then Lisp packages should not load the customization
9411 files at all.
9412
9413 ** format-time-string now allows you to specify the field width
9414 and type of padding. This works as in printf: you write the field
9415 width as digits in the middle of a %-construct. If you start
9416 the field width with 0, it means to pad with zeros.
9417
9418 For example, %S normally specifies the number of seconds since the
9419 minute; %03S means to pad this with zeros to 3 positions, %_3S to pad
9420 with spaces to 3 positions. Plain %3S pads with zeros, because that
9421 is how %S normally pads to two positions.
9422
9423 ** thing-at-point now supports a new kind of "thing": url.
9424
9425 ** imenu.el changes.
9426
9427 You can now specify a function to be run when selecting an
9428 item from menu created by imenu.
9429
9430 An example of using this feature: if we define imenu items for the
9431 #include directives in a C file, we can open the included file when we
9432 select one of those items.
9433 \f
9434 * For older news, see the file ONEWS
9435
9436 ----------------------------------------------------------------------
9437 Copyright information:
9438
9439 Copyright (C) 1999, 2000, 2001 Free Software Foundation, Inc.
9440
9441 Permission is granted to anyone to make or distribute verbatim copies
9442 of this document as received, in any medium, provided that the
9443 copyright notice and this permission notice are preserved,
9444 thus giving the recipient permission to redistribute in turn.
9445
9446 Permission is granted to distribute modified versions
9447 of this document, or of portions of it,
9448 under the above conditions, provided also that they
9449 carry prominent notices stating who last changed them.
9450 \f
9451 Local variables:
9452 mode: outline
9453 paragraph-separate: "[ \f]*$"
9454 end: