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1 GNU Emacs NEWS -- history of user-visible changes. 5 Jan 2000
2 Copyright (C) 1996, 1997, 1998, 1999, 2000 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 * Installation Changes in Emacs 21.1
10
11 ** `movemail' defaults to supporting POP. You can turn this off using
12 the --without-pop configure option, should that be necessary.
13
14 ** There are new configure options associated with the support for
15 images and toolkit scrollbars. Use the --help option to list them.
16 \f
17 * Changes in Emacs 21.1
18
19 ** The function `getenv' is now callable interactively.
20
21 ** The many obsolete language `setup-...-environment' commands have
22 been removed -- use `set-language-environment'.
23
24 ** New user options `display-time-mail-face' and
25 `display-time-use-mail-icon' control the appearance of mode-line mail
26 indicator used by the display-time package. On a suitable display the
27 indicator can be an icon and is mouse-sensitive.
28
29 ** Emacs' auto-save list files are now by default stored in a
30 sub-directory `.emacs.d/auto-save-list/' of the user's home directory.
31 (On MS-DOS, this subdirectory's name is `_emacs.d/auto-save.list/'.)
32 You can customize `auto-save-list-prefix' to change this location.
33
34 ** On window-systems, additional space can be put between text lines
35 on the display using several methods
36
37 - By setting frame parameter `line-spacing' to PIXELS. PIXELS must be
38 a positive integer, and specifies that PIXELS number of pixels should
39 be put below text lines on the affected frame or frames.
40
41 - By setting X resource `lineSpacing', class `LineSpacing'. This is
42 equivalent ot specifying the frame parameter.
43
44 - By specifying `--line-spacing=N' or `-lsp N' on the command line.
45
46 - By setting buffer-local variable `line-spacing'. The meaning is
47 the same, but applies to the a particular buffer only.
48
49 ** The new command `clone-buffer-indirectly' can be used to create
50 an indirect buffer that is a twin copy of the current buffer. The
51 command `clone-buffer-indirectly-other-window', bound to C-x 4 c,
52 does the same but displays the indirect buffer in another window.
53
54 ** New user options `backup-directory-alist' and
55 `make-backup-file-name-function' control the placement of backups,
56 typically in a single directory or in an invisible sub-directory.
57
58 ** New commands iso-iso2sgml and iso-sgml2iso convert between Latin-1
59 characters and the corresponding SGML (HTML) entities.
60
61 ** Emacs now refuses to load compiled Lisp files which weren't
62 compiled with Emacs. Set `load-dangerous-libraries' to t to change
63 this behavior.
64
65 The reason for this change is an incompatible change in XEmacs' byte
66 compiler. Files compiled with XEmacs can contain byte codes that let
67 Emacs dump core.
68
69 ** New X resources recognized
70
71 *** The X resource `synchronous', class `Synchronous', specifies
72 whether Emacs should run in synchronous mode. Synchronous mode
73 is useful for debugging X problems.
74
75 Example:
76
77 emacs.synchronous: true
78
79 *** The X resource `visualClass, class `VisualClass', specifies the
80 visual Emacs should use. The resource's value should be a string of
81 the form `CLASS-DEPTH', where CLASS is the name of the visual class,
82 and DEPTH is the requested color depth as a decimal number. Valid
83 visual class names are
84
85 TrueColor
86 PseudoColor
87 DirectColor
88 StaticColor
89 GrayScale
90 StaticGray
91
92 Visual class names specified as X resource are case-insensitive, i.e.
93 `pseudocolor', `Pseudocolor' and `PseudoColor' all have the same
94 meaning.
95
96 The program `xdpyinfo' can be used to list the visual classes
97 supported on your display, and which depths they have. If
98 `visualClass' is not specified, Emacs uses the display's default
99 visual.
100
101 Example:
102
103 emacs.visualClass: TrueColor-8
104
105 *** The X resource `privateColormap', class `PrivateColormap',
106 specifies that Emacs should use a private colormap if it is using the
107 default visual, and that visual is of class PseudoColor. Recognized
108 resource values are `true' or `on'.
109
110 Example:
111
112 emacs.privateColormap: true
113
114 ** The menu bar configuration has changed. The new configuration is
115 more CUA-compliant. The most significant change is that Options is
116 now a separate menu-bar item, with Mule and Customize as its submenus.
117
118 ** User-option `show-cursor-in-non-selected-windows' controls how to
119 display the cursor in non-selected windows. If nil, no cursor is
120 shown, if non-nil a hollow box cursor is shown. This option can
121 be customized.
122
123 ** The variable `echo-keystrokes' may now have a floating point value.
124
125 ** C-x 5 1 runs the new command delete-other-frames which deletes
126 all frames except the selected one.
127
128 ** If your init file is compiled (.emacs.elc), `user-init-file' is set
129 to the source name (.emacs.el), if that exists, after loading it.
130
131 ** The help string specified for a menu-item whose definition contains
132 the property `:help HELP' is now displayed under X either in the echo
133 area or with tooltips.
134
135 ** New user option `read-mail-command' specifies a command to use to
136 read mail from the menu etc.
137
138 ** Hexl contains a new command `hexl-insert-hex-string' which inserts
139 a string of hexadecimal numbers read from the mini-buffer.
140
141 ** Changes in Texinfo mode.
142
143 ** A couple of new key bindings have been added for inserting Texinfo
144 macros
145
146 Key binding Macro
147 -------------------------
148 C-c C-c C-s @strong
149 C-c C-c C-e @emph
150 C-c C-c u @url
151 C-c C-c q @quotation
152 C-c C-c m @email
153
154 ** Changes in Outline mode.
155
156 There is now support for Imenu to index headings. A new command
157 `outline-headers-as-kill' copies the visible headings in the region to
158 the kill ring, e.g. to produce a table of contents.
159
160 ** New command M-x check-parens can be used to find unbalanced paren
161 groups and strings in buffers in Lisp mode (or other modes).
162
163 ** You can now easily create new *Info* buffers using either M-x clone-buffer
164 or C-u m <entry> RET. M-x clone-buffer can also be used on *Help* and
165 several other special buffers.
166
167 ** Emacs can now support 'wheeled' mice (such as the MS IntelliMouse)
168 under XFree86. To enable this, simply put (mwheel-install) in your
169 .emacs file.
170
171 The variables `mwheel-follow-mouse' and `mwheel-scroll-amount'
172 determine where and by how much buffers are scrolled.
173
174 ** Listing buffers with M-x list-buffers (C-x C-b) now shows
175 abbreviated file names. Abbreviations can be customized by changing
176 `directory-abbrev-alist'.
177
178 ** Reading from the mini-buffer now reads from standard input if Emacs
179 is running in batch mode. For example,
180
181 (message "%s" (read t))
182
183 will read a Lisp expression from standard input and print the result
184 to standard output.
185
186 ** Faces and frame parameters.
187
188 There are four new faces `scroll-bar', `border', `cursor' and `mouse'.
189 Setting the frame parameters `scroll-bar-foreground' and
190 `scroll-bar-background' sets foreground and background color of face
191 `scroll-bar' and vice versa. Setting frame parameter `border-color'
192 sets the background color of face `border' and vice versa. Likewise
193 for frame parameters `cursor-color' and face `cursor', and frame
194 parameter `mouse-color' and face `mouse'.
195
196 Changing frame parameter `font' sets font-related attributes of the
197 `default' face and vice versa. Setting frame parameters
198 `foreground-color' or `background-color' sets the colors of the
199 `default' face and vice versa.
200
201 ** New face `menu'.
202
203 The face `menu' can be used to change colors and font of Emacs' menus.
204 Setting the font of LessTif/Motif menus is currently not supported;
205 attempts to set the font are ignored in this case.
206
207 ** New frame parameter `screen-gamma' for gamma correction.
208
209 The new frame parameter `screen-gamma' specifies gamma-correction for
210 colors. Its value may be nil, the default, in which case no gamma
211 correction occurs, or a number > 0, usually a float, that specifies
212 the screen gamma of a frame's display.
213
214 PC monitors usually have a screen gamma of 2.2. smaller values result
215 in darker colors. You might want to try a screen gamma of 1.5 for LCD
216 color displays. The viewing gamma Emacs uses is 0.4545. (1/2.2).
217
218 The X resource name of this parameter is `screenGamma', class
219 `ScreenGamma'.
220
221 ** Emacs has a new redisplay engine.
222
223 The new redisplay handles characters of variable width and height.
224 Italic text can be used without redisplay problems. Fonts containing
225 oversized characters, i.e. characters larger than the logical height
226 of a font can be used. Images of various formats can be displayed in
227 the text.
228
229 ** Emacs has a new face implementation.
230
231 The new faces no longer fundamentally use X font names to specify the
232 font. Instead, each face has several independent attributes--family,
233 height, width, weight and slant--that it may or may not specify.
234 These attributes can be merged from various faces, and then together
235 specify a font.
236
237 Faces are supported on terminals that can display color or fonts.
238 These terminal capabilities are auto-detected. Details can be found
239 under Lisp changes, below.
240
241 ** New default font is Courier 12pt.
242
243 ** When using a windowing terminal, Emacs window now has a cursor of
244 its own. When the window is selected, the cursor is solid; otherwise,
245 it is hollow.
246
247 ** Bitmap areas to the left and right of windows are used to display
248 truncation marks, continuation marks, overlay arrows and alike. The
249 foreground, background, and stipple of these areas can be changed by
250 customizing face `fringe'.
251
252 ** The mode line under X is now drawn with shadows by default. You
253 can change its appearance by modifying the face `modeline'.
254
255 ** LessTif support.
256
257 Emacs now runs with LessTif (see <http://www.lesstif.org>). You will
258 need a version 0.88.1 or later.
259
260 ** Toolkit scroll bars.
261
262 Emacs now uses toolkit scrollbars if available. When configured for
263 LessTif/Motif, it will use that toolkit's scrollbar. Otherwise, when
264 configured for Lucid and Athena widgets, it will use the Xaw3d scroll
265 bar if Xaw3d is available. You can turn off the use of toolkit scroll
266 bars by specifying `--with-toolkit-scroll-bars=no' when configuring
267 Emacs.
268
269 When you encounter problems with the Xaw3d scroll bar, watch out how
270 Xaw3d is compiled on your system. If the Makefile generated from
271 Xaw3d's Imakefile contains a `-DNARROWPROTO' compiler option, and your
272 Emacs system configuration file `s/your-system.h' does not contain a
273 define for NARROWPROTO, you might consider adding it. Take
274 `s/freebsd.h' as an example.
275
276 Alternatively, if you don't have access to the Xaw3d source code, take
277 a look at your system's imake configuration file, for example in the
278 directory `/usr/X11R6/lib/X11/config' (paths are different on
279 different systems). You will find files `*.cf' there. If your
280 system's cf-file contains a line like `#define NeedWidePrototypes NO',
281 add a `#define NARROWPROTO' to your Emacs system configuration file.
282
283 The reason for this is that one Xaw3d function uses `double' or
284 `float' function parameters depending on the setting of NARROWPROTO.
285 This is not a problem when Imakefiles are used because each system's
286 image configuration file contains the necessary information. Since
287 Emacs doesn't use imake, this has do be done manually.
288
289 ** Toggle buttons and radio buttons in menus.
290
291 When compiled with LessTif (or Motif) support, Emacs uses toolkit
292 widgets for radio and toggle buttons in menus. When configured for
293 Lucid, Emacs draws radio buttons and toggle buttons similar to Motif.
294
295 ** Highlighting of trailing whitespace.
296
297 When `show-trailing-whitespace' is non-nil, Emacs displays trailing
298 whitespace in the face `trailing-whitespace'. Trailing whitespace is
299 defined as spaces or tabs at the end of a line. To avoid busy
300 highlighting when entering new text, trailing whitespace is not
301 displayed if point is at the end of the line containing the
302 whitespace.
303
304 ** Busy-cursor.
305
306 Emacs can optionally display a busy-cursor under X. You can turn the
307 display on or off by customizing group `cursor'.
308
309 ** Blinking cursor
310
311 M-x blink-cursor-mode toggles a blinking cursor under X and on
312 terminals having terminal capabilities `vi', `vs', and `ve'. Blinking
313 and related parameters like frequency and delay can be customized in
314 the group `cursor'.
315
316 ** New font-lock support mode `jit-lock-mode'.
317
318 This support mode is roughly equivalent to `lazy-lock' but is
319 generally faster. It supports stealth and deferred fontification.
320 See the documentation of the function `jit-lock-mode' for more
321 details.
322
323 Font-lock uses jit-lock-mode as default support mode, so you don't
324 have to do anything to activate it.
325
326 ** Tabs and variable-width text.
327
328 Tabs are now displayed with stretch properties; the width of a tab is
329 defined as a multiple of the normal character width of a frame, and is
330 independent of the fonts used in the text where the tab appears.
331 Thus, tabs can be used to line up text in different fonts.
332
333 ** Enhancements of the Lucid menu bar
334
335 *** The Lucid menu bar now supports the resource "margin".
336
337 emacs.pane.menubar.margin: 5
338
339 The default margin is 4 which makes the menu bar appear like the
340 LessTif/Motif one.
341
342 *** Arrows that indicate sub-menus are now drawn with shadows, as in
343 LessTif and Motif.
344
345 ** Hscrolling in C code.
346
347 Horizontal scrolling now happens automatically if
348 `automatic-hscrolling' is set (the default). This setting can be
349 customized.
350
351 ** Tool bar support.
352
353 Emacs supports a tool bar at the top of a frame under X. For details
354 how to define a tool bar, see the page describing Lisp-level changes.
355
356 ** Mouse-sensitive mode line.
357
358 Different parts of the mode line under X have been made
359 mouse-sensitive. Moving the mouse to a mouse-sensitive part in the mode
360 line changes the appearance of the mouse pointer to an arrow, and help
361 about available mouse actions is displayed either in the echo area, or
362 in the tooltip window if you have enabled one.
363
364 Currently, the following actions have been defined:
365
366 - Mouse-1 on the buffer name in the mode line switches between two
367 buffers.
368
369 - Mouse-2 on the buffer-name switches to the next buffer, and
370 M-mouse-2 switches to the previous buffer in the buffer list.
371
372 - Mouse-3 on the buffer-name displays a buffer menu.
373
374 - Mouse-2 on the read-only status in the mode line (`%' or `*')
375 toggles the read-only status.
376
377 - Mouse-3 on the mode name display a minor-mode menu.
378
379 ** LessTif/Motif file selection dialog.
380
381 When Emacs is configured to use LessTif or Motif, reading a file name
382 from a menu will pop up a file selection dialog if `use-dialog-box' is
383 non-nil.
384
385 ** Emacs can display faces on TTY frames.
386
387 Emacs automatically detects terminals that are able to display colors.
388 Faces with a weight greater than normal are displayed extra-bright, if
389 the terminal supports it. Faces with a weight less than normal and
390 italic faces are displayed dimmed, if the terminal supports it.
391 Underlined faces are displayed underlined if possible. Other face
392 attributes like overlines, strike-throught, box are ignored.
393
394 ** Sound support
395
396 Emacs supports playing sound files on GNU/Linux and the free BSDs
397 (Voxware driver and native BSD driver, aka as Luigi's driver).
398 Currently supported file formats are RIFF-WAVE (*.wav) and Sun Audio
399 (*.au). You must configure Emacs with the option `--with-sound=yes'
400 to enable sound support.
401
402 ** A new variable, backup-by-copying-when-privileged-mismatch, gives
403 the highest file uid for which backup-by-copying-when-mismatch will be
404 forced on. The assumption is that uids less than or equal to this
405 value are special uids (root, bin, daemon, etc.--not real system
406 users) and that files owned by these users should not change ownership,
407 even if your system policy allows users other than root to edit them.
408
409 The default is 200; set the variable to nil to disable the feature.
410
411 ** A block cursor can be drawn as wide as the glyph under it under X.
412
413 As an example: if a block cursor is over a tab character, it will be
414 drawn as wide as that tab on the display. To do this, set
415 `x-stretch-cursor' to a non-nil value.
416
417 ** Empty display lines at the end of a buffer may be marked with a
418 bitmap (this is similar to the tilde displayed by vi).
419
420 This behavior is activated by setting the buffer-local variable
421 `indicate-empty-lines' to a non-nil value. The default value of this
422 variable is found in `default-indicate-empty-lines'.
423
424 ** There is a new "aggressive" scrolling method.
425
426 When scrolling up because point is above the window start, if the
427 value of the buffer-local variable `scroll-up-aggessively' is a
428 number, Emacs chooses a new window start so that point ends up that
429 fraction of the window's height from the bottom of the window.
430
431 When scrolling down because point is below the window end, if the
432 value of the buffer-local variable `scroll-down-aggessively' is a
433 number, Emacs chooses a new window start so that point ends up that
434 fraction of the window's height from the top of the window.
435
436 ** The rectangle commands now avoid inserting undesirable spaces,
437 notably at the end of lines.
438
439 All these functions have been rewritten to avoid inserting unwanted
440 spaces, and an optional prefix now allows them to behave the old way.
441
442 There is a new command M-x replace-rectangle.
443
444 ** The new command M-x query-replace-regexp-eval acts like
445 query-replace-regexp, but takes a Lisp expression which is evaluated
446 after each match to get the replacement text.
447
448 ** M-x query-replace recognizes a new command `E' that lets you
449 edit the replacement string.
450
451 ** The new command mail-abbrev-complete-alias, bound to `M-TAB', let's
452 you complete mail aliases in the text, analogous to
453 lisp-complete-symbol.
454
455 ** Emacs now resizes mini-windows if appropriate.
456
457 If a message is longer than one line, or mini-buffer contents are
458 longer than one line, Emacs now resizes the mini-window unless it is
459 on a frame of its own. You can control the maximum mini-window size
460 by setting the following variable:
461
462 - User option: max-mini-window-height
463
464 Maximum height for resizing mini-windows. If a float, it specifies a
465 fraction of the mini-window frame's height. If an integer, it
466 specifies a number of lines. If nil, don't resize.
467
468 Default is 0.25.
469
470 ** Changes to hideshow.el
471
472 Hideshow is now at version 5.x. It uses a new algorithms for block
473 selection and traversal and includes more isearch support.
474
475 *** Generalized block selection and traversal
476
477 A block is now recognized by three things: its start and end regexps
478 (both strings), and a match-data selector (an integer) specifying
479 which sub-expression in the start regexp serves as the place where a
480 `forward-sexp'-like function can operate. Hideshow always adjusts
481 point to this sub-expression before calling `hs-forward-sexp-func'
482 (which for most modes evaluates to `forward-sexp').
483
484 If the match-data selector is not specified, it defaults to zero,
485 i.e., the entire start regexp is valid, w/ no prefix. This is
486 backwards compatible with previous versions of hideshow. Please see
487 the docstring for variable `hs-special-modes-alist' for details.
488
489 *** Isearch support for updating mode line
490
491 During incremental search, if Hideshow minor mode is active, hidden
492 blocks are temporarily shown. The variable `hs-headline' records the
493 line at the beginning of the opened block (preceding the hidden
494 portion of the buffer), and the mode line is refreshed. When a block
495 is re-hidden, the variable is set to nil.
496
497 To show `hs-headline' in the mode line, you may wish to include
498 something like this in your .emacs.
499
500 (add-hook 'hs-minor-mode-hook
501 (lambda ()
502 (add-to-list 'mode-line-format 'hs-headline)))
503
504 ** Changes to Change Log mode and Add-Log functions
505
506 If you invoke `add-change-log-entry' from a backup file, it makes an
507 entry appropriate for the file's parent. This is useful for making
508 log entries by comparing a version with deleted functions.
509
510 New command M-x change-log-merge merges another log into the current
511 buffer, fixing old-style date formats if necessary.
512
513 Change Log mode now adds a file's version number to change log entries
514 if user-option `change-log-version-info-enabled' is non-nil.
515
516 The search for a file's version number is performed based on regular
517 expressions from `change-log-version-number-regexp-list' which can be
518 cutomized. Version numbers are only found in the first 10 percent of
519 a file.
520
521 ** Changes in Font Lock
522
523 *** The new function `font-lock-remove-keywords' can be used to remove
524 font-lock keywords from the current buffer or from a specific major
525 mode.
526
527 ** Comint (subshell) changes
528
529 Comint now includes new features to send commands to running processes
530 and redirect the output to a designated buffer or buffers.
531
532 The command M-x comint-redirect-send-command reads a command and
533 buffer name from the mini-buffer. The command is sent to the current
534 buffer's process, and its output is inserted into the specified buffer.
535
536 The command M-x comint-redirect-send-command-to-process acts like
537 M-x comint-redirect-send-command but additionally reads the name of
538 the buffer whose process should be used from the mini-buffer.
539
540 ** Changes to Rmail mode
541
542 *** The new user-option rmail-rmail-user-mail-address-regexp can be
543 set to fine tune the identification of of the correspondent when
544 receiving new mail. If it matches the address of the sender, the
545 recipient is taken as correspondent of a mail. If nil, the default,
546 `user-login-name' and `user-mail-address' are used to exclude yourself
547 as correspondent.
548
549 Usually you don't have to set this variable, except if you collect
550 mails sent by you under different user names. Then it should be a
551 regexp matching your mail addresses.
552
553 *** The new user-option rmail-confirm-expunge controls whether and how
554 to ask for confirmation before expunging deleted messages from an
555 Rmail file. You can choose between no confirmation, confirmation
556 with y-or-n-p, or confirmation with yes-or-no-p. Default is to ask
557 for confirmation with yes-or-no-p.
558
559 *** RET is now bound in the Rmail summary to rmail-summary-goto-msg,
560 like `j'.
561
562 *** There is a new user option `rmail-digest-end-regexps' that
563 specifies the regular expressions to detect the line that ends a
564 digest message.
565
566 *** The new user option `rmail-automatic-folder-directives' specifies
567 in which folder to put messages automatically.
568
569 ** Changes to TeX mode
570
571 The default mode has been changed from `plain-tex-mode' to
572 `latex-mode'.
573
574 ** Changes to RefTeX mode
575
576 *** RefTeX has new support for index generation. Index entries can be
577 created with `C-c <', with completion available on index keys.
578 Pressing `C-c /' indexes the word at the cursor with a default
579 macro. `C-c >' compiles all index entries into an alphabetically
580 sorted *Index* buffer which looks like the final index. Entries
581 can be edited from that buffer.
582
583 *** Label and citation key selection now allow to select several
584 items and reference them together (use `m' to mark items, `a' or
585 `A' to use all marked entries).
586
587 *** reftex.el has been split into a number of smaller files to reduce
588 memory use when only a part of RefTeX is being used.
589
590 *** a new command `reftex-view-crossref-from-bibtex' (bound to `C-c &'
591 in BibTeX-mode) can be called in a BibTeX database buffer in order
592 to show locations in LaTeX documents where a particular entry has
593 been cited.
594
595 ** Emacs Lisp mode now allows multiple levels of outline headings.
596 The level of a heading is determined from the number of leading
597 semicolons in a heading line. Toplevel forms starting with a `('
598 in column 1 are always made leaves.
599
600 ** The M-x time-stamp command (most commonly used on write-file-hooks)
601 has the following new features:
602
603 *** The patterns for finding the time stamp and for updating a pattern
604 may match text spanning multiple lines. For example, some people like
605 to have the filename and date on separate lines. The new variable
606 time-stamp-inserts-lines controls the matching for multi-line patterns.
607
608 *** More than one time stamp can be updated in the same file. This
609 feature is useful if you need separate time stamps in a program source
610 file to both include in formatted documentation and insert in the
611 compiled binary. The same time-stamp will be written at each matching
612 pattern. The variable time-stamp-count enables this new feature; it
613 defaults to 1.
614
615 ** Tooltips.
616
617 Tooltips are small X windows displaying a help string at the current
618 mouse position. To use them, use the Lisp package `tooltip' which you
619 can access via the user option `tooltip-mode'.
620
621 Tooltips also provides support for GUD debugging. If activated,
622 variable values can be displayed in tooltips by pointing at them with
623 the mouse in source buffers. You can customize various aspects of the
624 tooltip display in the group `tooltip'.
625
626 ** Customize changes
627
628 *** Customize now supports comments about customized items. Use the
629 `State' menu to add comments. Note that customization comments will
630 cause the customizations to fail in earlier versions of Emacs.
631
632 *** The new option `custom-buffer-done-function' says whether to kill
633 Custom buffers when you've done with them or just bury them (the
634 default).
635
636 *** The keyword :set-after in defcustom allows to specify dependencies
637 between custom options. Example:
638
639 (defcustom default-input-method nil
640 "*Default input method for multilingual text (a string).
641 This is the input method activated automatically by the command
642 `toggle-input-method' (\\[toggle-input-method])."
643 :group 'mule
644 :type '(choice (const nil) string)
645 :set-after '(current-language-environment))
646
647 This specifies that default-input-method should be set after
648 current-language-environment even if default-input-method appears
649 first in a custom-set-variables statement.
650
651 ** New features in evaluation commands
652
653 The commands to evaluate Lisp expressions, such as C-M-x in Lisp
654 modes, C-j in Lisp Interaction mode, and M-:, now bind the variables
655 print-level, print-length, and debug-on-error based on the
656 customizable variables eval-expression-print-level,
657 eval-expression-print-length, and eval-expression-debug-on-error.
658
659 ** Dired changes
660
661 *** New variable `dired-recursive-deletes' determines if the delete
662 command will delete non-empty directories recursively. The default
663 is, delete only empty directories.
664
665 *** New variable `dired-recursive-copies' determines if the copy
666 command will copy directories recursively. The default is, do not
667 copy directories recursively.
668
669 *** In command `dired-do-shell-command' (usually bound to `!') a `?'
670 in the shell command has a special meaning similar to `*', but with
671 the difference that the command will be run on each file individually.
672
673 ** The variable mail-specify-envelope-from controls whether to
674 use the -f option when sending mail.
675
676 ** CC mode changes.
677
678 Note: This release contains changes that might not be compatible with
679 current user setups (although it's believed that these
680 incompatibilities will only show in very uncommon circumstances).
681 However, since the impact is uncertain, these changes may be rolled
682 back depending on user feedback. Therefore there's no forward
683 compatibility guarantee wrt the new features introduced in this
684 release.
685
686 *** New initialization procedure for the style system.
687 When the initial style for a buffer is determined by CC Mode (from the
688 variable c-default-style), the global values of style variables now
689 take precedence over the values specified by the chosen style. This
690 is different than the old behavior: previously, the style-specific
691 settings would override the global settings. This change makes it
692 possible to do simple configuration in the intuitive way with
693 Customize or with setq lines in one's .emacs file.
694
695 By default, the global value of every style variable is the new
696 special symbol set-from-style, which causes the value to be taken from
697 the style system. This means that in effect, only an explicit setting
698 of a style variable will cause the "overriding" behavior described
699 above.
700
701 Also note that global settings override style-specific settings *only*
702 when the initial style of a buffer is chosen by a CC Mode major mode
703 function. When a style is chosen in other ways --- for example, by a
704 call like (c-set-style "gnu") in a hook, or via M-x c-set-style ---
705 then the style-specific values take precedence over any global style
706 values. In Lisp terms, global values override style-specific values
707 only when the new second argument to c-set-style is non-nil; see the
708 function documentation for more info.
709
710 The purpose of these changes is to make it easier for users,
711 especially novice users, to do simple customizations with Customize or
712 with setq in their .emacs files. On the other hand, the new system is
713 intended to be compatible with advanced users' customizations as well,
714 such as those that choose styles in hooks or whatnot. This new system
715 is believed to be almost entirely compatible with current
716 configurations, in spite of the changed precedence between style and
717 global variable settings when a buffer's default style is set.
718
719 (Thanks to Eric Eide for clarifying this explanation a bit.)
720
721 **** c-offsets-alist is now a customizable variable.
722 This became possible as a result of the new initialization behavior.
723
724 This variable is treated slightly differently from the other style
725 variables; instead of using the symbol set-from-style, it will be
726 completed with the syntactic symbols it doesn't already contain when
727 the style is first initialized. This means it now defaults to the
728 empty list to make all syntactic elements get their values from the
729 style system.
730
731 **** Compatibility variable to restore the old behavior.
732 In case your configuration doesn't work with this change, you can set
733 c-old-style-variable-behavior to non-nil to get the old behavior back
734 as far as possible.
735
736 *** Improvements to line breaking and text filling.
737 CC Mode now handles this more intelligently and seamlessly wrt the
738 surrounding code, especially inside comments. For details see the new
739 chapter about this in the manual.
740
741 **** New variable to recognize comment line prefix decorations.
742 The variable c-comment-prefix-regexp has been added to properly
743 recognize the line prefix in both block and line comments. It's
744 primarily used to initialize the various paragraph recognition and
745 adaptive filling variables that the text handling functions uses.
746
747 **** New variable c-block-comment-prefix.
748 This is a generalization of the now obsolete variable
749 c-comment-continuation-stars to handle arbitrary strings.
750
751 **** CC Mode now uses adaptive fill mode.
752 This to make it adapt better to the paragraph style inside comments.
753
754 It's also possible to use other adaptive filling packages inside CC
755 Mode, notably Kyle E. Jones' Filladapt mode (http://wonderworks.com/).
756 A new convenience function c-setup-filladapt sets up Filladapt for use
757 inside CC Mode.
758
759 Note though that the 2.12 version of Filladapt lacks a feature that
760 causes it to work suboptimally when c-comment-prefix-regexp can match
761 the empty string (which it commonly does). A patch for that is
762 available from the CC Mode web site (http://www.python.org/emacs/
763 cc-mode/).
764
765 **** It's now possible to selectively turn off auto filling.
766 The variable c-ignore-auto-fill is used to ignore auto fill mode in
767 specific contexts, e.g. in preprocessor directives and in string
768 literals.
769
770 **** New context sensitive line break function c-context-line-break.
771 It works like newline-and-indent in normal code, and adapts the line
772 prefix according to the comment style when used inside comments. If
773 you're normally using newline-and-indent, you might want to switch to
774 this function.
775
776 *** Fixes to IDL mode.
777 It now does a better job in recognizing only the constructs relevant
778 to IDL. E.g. it no longer matches "class" as the beginning of a
779 struct block, but it does match the CORBA 2.3 "valuetype" keyword.
780 Thanks to Eric Eide.
781
782 *** Improvements to the Whitesmith style.
783 It now keeps the style consistently on all levels and both when
784 opening braces hangs and when they don't.
785
786 **** New lineup function c-lineup-whitesmith-in-block.
787
788 *** New lineup functions c-lineup-template-args and c-indent-multi-line-block.
789 See their docstrings for details. c-lineup-template-args does a
790 better job of tracking the brackets used as parens in C++ templates,
791 and is used by default to line up continued template arguments.
792
793 *** c-lineup-comment now preserves alignment with a comment on the
794 previous line. It used to instead preserve comments that started in
795 the column specified by comment-column.
796
797 *** c-lineup-C-comments handles "free form" text comments.
798 In comments with a long delimiter line at the start, the indentation
799 is kept unchanged for lines that start with an empty comment line
800 prefix. This is intended for the type of large block comments that
801 contain documentation with its own formatting. In these you normally
802 don't want CC Mode to change the indentation.
803
804 *** The `c' syntactic symbol is now relative to the comment start
805 instead of the previous line, to make integers usable as lineup
806 arguments.
807
808 *** All lineup functions have gotten docstrings.
809
810 *** More preprocessor directive movement functions.
811 c-down-conditional does the reverse of c-up-conditional.
812 c-up-conditional-with-else and c-down-conditional-with-else are
813 variants of these that also stops at "#else" lines (suggested by Don
814 Provan).
815
816 *** Minor improvements to many movement functions in tricky situations.
817
818 ** Makefile mode changes
819
820 *** The mode now uses the abbrev table `makefile-mode-abbrev-table'.
821
822 *** Conditionals and include statements are now highlighted when
823 Fontlock mode is active.
824
825 ** Isearch changes
826
827 ** In Isearch mode, M-C-s and M-C-r are now bound like C-s and C-r,
828 respectively, i.e. you can repeat a regexp isearch with the same keys
829 that started the search.
830
831 *** In Isearch mode, mouse-2 in the echo area now yanks the current
832 selection into the search string rather than giving an error.
833
834 *** There is a new lazy highlighting feature in incremental search.
835
836 Lazy highlighting is switched on/off by customizing variable
837 `isearch-lazy-highlight'. When active, all matches for the current
838 search string are highlighted. The current match is highlighted as
839 before using face `isearch' or `region'. All other matches are
840 highlighted using face `isearch-lazy-highlight-face' which defaults to
841 `secondary-selection'.
842
843 The extra highlighting makes it easier to anticipate where the cursor
844 will end up each time you press C-s or C-r to repeat a pending search.
845 Highlighting of these additional matches happens in a deferred fashion
846 using "idle timers," so the cycles needed do not rob isearch of its
847 usual snappy response.
848
849 If `isearch-lazy-highlight-cleanup' is set to t, highlights for
850 matches are automatically cleared when you end the search. If it is
851 set to nil, you can remove the highlights manually with `M-x
852 isearch-lazy-highlight-cleanup'.
853
854 ** Changes in sort.el
855
856 The function sort-numeric-fields interprets numbers starting with `0'
857 as octal and numbers starting with `0x' or `0X' as hexadecimal. The
858 new user-option sort-numberic-base can be used to specify a default
859 numeric base.
860
861 ** Changes to Ange-ftp
862
863 *** Ange-ftp allows you to specify of a port number in remote file
864 names cleanly. It is appended to the host name, separated by a hash
865 sign, e.g. `/foo@bar.org#666:mumble'. (This syntax comes from EFS.)
866
867 *** If the new user-option `ange-ftp-try-passive-mode' is set, passive
868 ftp mode will be used if the ftp client supports that.
869
870 ** Shell script mode changes.
871
872 Shell script mode (sh-script) can now indent scripts for shells
873 derived from sh and rc. The indentation style is customizeable, and
874 sh-script can attempt to "learn" the current buffer's style.
875
876 ** Etags changes.
877
878 *** In DOS, etags looks for file.cgz if it cannot find file.c.
879
880 *** New option --ignore-case-regex is an alternative to --regex. It is now
881 possible to bind a regexp to a language, by prepending the regexp with
882 {lang}, where lang is one of the languages that `etags --help' prints out.
883 This feature is useful especially for regex files, where each line contains
884 a regular expression. The manual contains details.
885
886 *** In C and derived languages, etags creates tags for function
887 declarations when given the --declarations option.
888
889 *** In C++, tags are created for "operator". The tags have the form
890 "operator+", without spaces between the keyword and the operator.
891
892 *** New language Ada: tags are functions, procedures, packages, tasks, and
893 types.
894
895 *** In Fortran, procedure is no more tagged.
896
897 *** In Java, tags are created for "interface".
898
899 *** In Lisp, "(defstruct (foo", "(defun (operator" and similar constructs
900 are now tagged.
901
902 *** In Perl, the --globals option tags global variables. my and local
903 variables are tagged.
904
905 *** New language Python: def and class at the beginning of a line are tags.
906
907 *** .ss files are Scheme files, .pdb is Postscript with C syntax, .psw is
908 for PSWrap.
909
910 ** Changes in etags.el
911
912 *** The new user-option tags-case-fold-search can be used to make
913 tags operations case-sensitive or case-insensitive. The default
914 is to use the same setting as case-fold-search.
915
916 *** You can display additional output with M-x tags-apropos by setting
917 the new variable tags-apropos-additional-actions.
918
919 If non-nil, the variable's value should be a list of triples (TITLE
920 FUNCTION TO-SEARCH). For each triple, M-x tags-apropos processes
921 TO-SEARCH and lists tags from it. TO-SEARCH should be an alist,
922 obarray, or symbol. If it is a symbol, the symbol's value is used.
923
924 TITLE is a string to use to label the list of tags from TO-SEARCH.
925
926 FUNCTION is a function to call when an entry is selected in the Tags
927 List buffer. It is called with one argument, the selected symbol.
928
929 A useful example value for this variable might be something like:
930
931 '(("Emacs Lisp" Info-goto-emacs-command-node obarray)
932 ("Common Lisp" common-lisp-hyperspec common-lisp-hyperspec-obarray)
933 ("SCWM" scwm-documentation scwm-obarray))
934
935 *** The face tags-tag-face can be used to customize the appearance
936 of tags in the output of M-x tags-apropos.
937
938 *** Setting tags-apropos-verbose to a non-nil value displays the
939 names of tags files in the *Tags List* buffer.
940
941 ** Emacs now attempts to determine the initial language environment
942 and preferred and locale coding systems systematically from the
943 LC_ALL, LC_CTYPE, and LANG environment variables during startup.
944
945 ** New language environments `Latin-8' and `Latin-9'.
946 These correspond respectively to the ISO character sets 8859-14
947 (Celtic) and 8859-15 (updated Latin-1, with the Euro sign). There is
948 currently no specific input method support for them.
949
950 ** Fortran mode has a new command `fortran-strip-sqeuence-nos' to
951 remove text past column 72. The syntax class of `\' in Fortran is now
952 appropriate for C-style escape sequences in strings.
953
954 ** SGML mode's default `sgml-validate-command' is now `nsgmls'.
955
956 ** A new command `view-emacs-problems' (C-h P) displays the PROBLEMS file.
957
958 ** The Dabbrev package has a new user-option `dabbrev-ignore-regexps'
959 containing a list of regular expressions. Buffers matching a regular
960 expression from that list, are not checked.
961
962 ** New modes and packages
963
964 *** The Ebrowse package implements a C++ class browser and tags
965 facilities tailored for use with C++. It is documented in a
966 separate Texinfo file.
967
968 *** The PCL-CVS package available by either running M-x cvs-examine
969 or by visiting a CVS administrative directory (with a prefix argument)
970 provides an alternative interface to VC-dired for CVS.
971 It comes with log-view-mode to view RCS and SCCS logs and log-edit-mode
972 used to enter checkin log messages.
973
974 *** The new package called `woman' allows to browse Unix man pages
975 without invoking external programs.
976
977 The command `M-x woman' formats manual pages entirely in Emacs Lisp
978 and then displays them, like `M-x manual-entry' does. Unlike
979 `manual-entry', `woman' does not invoke any external programs, so it
980 is useful on systems such as MS-DOS/MS-Windows where the `man' and
981 Groff or `troff' commands are not readily available.
982
983 The command `M-x woman-find-file' asks for the file name of a man
984 page, then formats and displays it like `M-x woman' does.
985
986 *** The new command M-x re-builder offers a convenient interface for
987 authoring regular expressions with immediate visual feedback.
988
989 The buffer from which the command was called becomes the target for
990 the regexp editor popping up in a separate window. Matching text in
991 the target buffer is immediately color marked during the editing.
992 Each sub-expression of the regexp will show up in a different face so
993 even complex regexps can be edited and verified on target data in a
994 single step.
995
996 On displays not supporting faces the matches instead blink like
997 matching parens to make them stand out. On such a setup you will
998 probably also want to use the sub-expression mode when the regexp
999 contains such to get feedback about their respective limits.
1000
1001 *** glasses-mode is a minor mode that makes
1002 unreadableIdentifiersLikeThis readable. It works as glasses, without
1003 actually modifying content of a buffer.
1004
1005 *** The package ebnf2ps translates an EBNF to a syntactic chart in
1006 PostScript.
1007
1008 Currently accepts ad-hoc EBNF, ISO EBNF and Bison/Yacc.
1009
1010 The ad-hoc default EBNF syntax has the following elements:
1011
1012 ; comment (until end of line)
1013 A non-terminal
1014 "C" terminal
1015 ?C? special
1016 $A default non-terminal
1017 $"C" default terminal
1018 $?C? default special
1019 A = B. production (A is the header and B the body)
1020 C D sequence (C occurs before D)
1021 C | D alternative (C or D occurs)
1022 A - B exception (A excluding B, B without any non-terminal)
1023 n * A repetition (A repeats n (integer) times)
1024 (C) group (expression C is grouped together)
1025 [C] optional (C may or not occurs)
1026 C+ one or more occurrences of C
1027 {C}+ one or more occurrences of C
1028 {C}* zero or more occurrences of C
1029 {C} zero or more occurrences of C
1030 C / D equivalent to: C {D C}*
1031 {C || D}+ equivalent to: C {D C}*
1032 {C || D}* equivalent to: [C {D C}*]
1033 {C || D} equivalent to: [C {D C}*]
1034
1035 Please, see ebnf2ps documentation for EBNF syntax and how to use it.
1036
1037 *** The package align.el will align columns within a region, using M-x
1038 align. Its mode-specific rules, based on regular expressions,
1039 determine where the columns should be split. In C and C++, for
1040 example, it will align variable names in declaration lists, or the
1041 equal signs of assignments.
1042
1043 *** `paragraph-indent-minor-mode' is a new minor mode supporting
1044 paragraphs in the same style as `paragraph-indent-text-mode'.
1045
1046 *** bs.el is a new package for buffer selection similar to
1047 list-buffers or electric-buffer-list. Use M-x bs-show to display a
1048 buffer menu with this package. You can use M-x bs-customize to
1049 customize the package.
1050
1051 *** calculator.el is a small calculator package that is intended to
1052 replace desktop calculators such as xcalc and calc.exe. Actually, it
1053 is not too small - it has more features than most desktop calculators,
1054 and can be customized easily to get many more functions. It should
1055 not be confused with "calc" which is a much bigger mathematical tool
1056 which answers different needs.
1057
1058 *** The minor modes cwarn-mode and global-cwarn-mode highlights
1059 suspicious C and C++ constructions. Currently, assignments inside
1060 expressions, semicolon following `if', `for' and `while' (except, of
1061 course, after a `do .. while' statement), and C++ functions with
1062 reference parameters are recognized. The modes require font-lock mode
1063 to be enabled.
1064
1065 *** smerge-mode.el provides `smerge-mode', a simple minor-mode for files
1066 containing diff3-style conflict markers, such as generated by RCS.
1067
1068 *** 5x5.el is a simple puzzle game.
1069
1070 *** hl-line.el provides a minor mode to highlight the current line.
1071
1072 *** ansi-color.el translates ANSI terminal escapes into text-properties.
1073
1074 *** delphi.el provides a major mode for editing the Delphi (Object
1075 Pascal) language.
1076
1077 *** quickurl.el provides a simple method of inserting a URL based on
1078 the text at point.
1079
1080 *** sql.el provides an interface to SQL data bases.
1081
1082 *** fortune.el uses the fortune program to create mail/news signatures.
1083
1084 *** whitespace.el ???
1085
1086 *** PostScript mode (ps-mode) is a new major mode for editing PostScript
1087 files. It offers: interaction with a PostScript interpreter, including
1088 (very basic) error handling; fontification, easily customizable for
1089 interpreter messages; auto-indentation; insertion of EPSF templates and
1090 often used code snippets; viewing of BoundingBox; commenting out /
1091 uncommenting regions; conversion of 8bit characters to PostScript octal
1092 codes. All functionality is accessible through a menu.
1093
1094 *** delim-col helps to prettify columns in a text region or rectangle.
1095
1096 Here is an example of columns:
1097
1098 horse apple bus
1099 dog pineapple car EXTRA
1100 porcupine strawberry airplane
1101
1102 Doing the following settings:
1103
1104 (setq delimit-columns-str-before "[ ")
1105 (setq delimit-columns-str-after " ]")
1106 (setq delimit-columns-str-separator ", ")
1107 (setq delimit-columns-separator "\t")
1108
1109
1110 Selecting the lines above and typing:
1111
1112 M-x delimit-columns-region
1113
1114 It results:
1115
1116 [ horse , apple , bus , ]
1117 [ dog , pineapple , car , EXTRA ]
1118 [ porcupine, strawberry, airplane, ]
1119
1120 delim-col has the following options:
1121
1122 delimit-columns-str-before Specify a string to be inserted
1123 before all columns.
1124
1125 delimit-columns-str-separator Specify a string to be inserted
1126 between each column.
1127
1128 delimit-columns-str-after Specify a string to be inserted
1129 after all columns.
1130
1131 delimit-columns-separator Specify a regexp which separates
1132 each column.
1133
1134 delim-col has the following commands:
1135
1136 delimit-columns-region Prettify all columns in a text region.
1137 delimit-columns-rectangle Prettify all columns in a text rectangle.
1138
1139 *** The package recentf.el maintains a menu for visiting files that
1140 were operated on recently. When enabled, a new "Open Recent" submenu
1141 is displayed in the "Files" menu.
1142
1143 The recent files list is automatically saved across Emacs sessions.
1144
1145 To enable/disable recentf use M-x recentf-mode.
1146
1147 To enable recentf at Emacs startup use
1148 M-x customize-variable RET recentf-mode RET.
1149
1150 To change the number of recent files displayed and others options use
1151 M-x customize-group RET recentf RET.
1152
1153 *** elide-head.el provides a mechanism for eliding boilerplate header
1154 text.
1155
1156 *** footnote.el provides `footnote-mode', a minor mode supporting use
1157 of footnotes. It is intended for use with Message mode, but isn't
1158 specific to Message mode.
1159
1160 *** diff-mode.el provides `diff-mode', a major mode for
1161 viewing/editing context diffs (patches). It is selected for files
1162 with extension `.diff', `.diffs', `.patch' and `.rej'.
1163
1164 *** EUDC, the Emacs Unified Directory Client, provides a common user
1165 interface to access directory servers using different directory
1166 protocols. It has a separate manual.
1167
1168 *** autoconf.el provides a major mode for editing configure.in files
1169 for Autoconf, selected automatically.
1170
1171 *** windmove.el provides moving between windows.
1172
1173 *** crm.el provides a facility to read multiple strings from the
1174 minibuffer with completion.
1175
1176 *** todo-mode.el provides management of TODO lists and integration
1177 with the diary features.
1178
1179 *** autoarg.el provides a feature reported from Twenex Emacs whereby
1180 numeric keys supply prefix args rather than self inserting.
1181
1182 ** Withdrawn packages
1183
1184 *** mldrag.el has been removed. mouse.el provides the same
1185 functionality with aliases for the mldrag functions.
1186
1187 *** eval-reg.el has been obsoleted by changes to edebug.el and removed.
1188
1189 *** ph.el has been obsoleted by EUDC and removed.
1190
1191 \f
1192 * Lisp changes made after edition 2.6 of the Emacs Lisp Manual,
1193 (Display-related features are described in a page of their own below.)
1194
1195 \f
1196 * Lisp changes in Emacs 21.1 (see following page for display-related features)
1197
1198 Note that +++ before an item means the Lisp manual has been updated.
1199 --- means that I have decided it does not need to be in the Lisp manual.
1200 When you add a new item, please add it without either +++ or ---
1201 so I will know I still need to look at it -- rms.
1202
1203 +++
1204 ** If the APPEND argument of `write-region' is an integer, it seeks to
1205 that offset in the file before writing.
1206
1207 ** `concat' no longer accepts individual integer arguments, as
1208 promised long ago.
1209
1210 ** The function `add-minor-mode' simplifies the definition of minor
1211 modes.
1212
1213 - Function: add-minor-mode TOGGLE NAME &optional KEYMAP AFTER TOGGLE-FUN
1214
1215 Register a new minor mode.
1216
1217 TOGGLE is a symbol which is the name of a buffer-local variable that
1218 is toggled on or off to say whether the minor mode is active or not.
1219
1220 NAME specifies what will appear in the mode line when the minor mode
1221 is active. NAME should be either a string starting with a space, or a
1222 symbol whose value is such a string.
1223
1224 Optional KEYMAP is the keymap for the minor mode that will be added
1225 to `minor-mode-map-alist'.
1226
1227 Optional AFTER specifies that TOGGLE should be added after AFTER
1228 in `minor-mode-alist'.
1229
1230 Optional TOGGLE-FUN is there for compatiblity with other Emacssen.
1231 It is currently not used.
1232
1233 ** The function `shell-command' now sets the default directory of the
1234 `*Shell Command Output*' buffer to the default directory of the buffer
1235 from which the command was issued.
1236
1237 ** The functions `query-replace', `query-replace-regexp',
1238 `query-replace-regexp-eval' `map-query-replace-regexp',
1239 `replace-string', `replace-regexp', and `perform-replace' take two
1240 additional optional arguments START and END that specify the region to
1241 operate on.
1242
1243 ** The new function `count-screen-lines' is a more flexible alternative
1244 to `window-buffer-height'.
1245
1246 - Function: count-screen-lines &optional BEG END COUNT-FINAL-NEWLINE WINDOW
1247
1248 Return the number of screen lines in the region between BEG and END.
1249 The number of screen lines may be different from the number of actual
1250 lines, due to line breaking, display table, etc.
1251
1252 Optional arguments BEG and END default to `point-min' and `point-max'
1253 respectively.
1254
1255 If region ends with a newline, ignore it unless optinal third argument
1256 COUNT-FINAL-NEWLINE is non-nil.
1257
1258 The optional fourth argument WINDOW specifies the window used for
1259 obtaining parameters such as width, horizontal scrolling, and so
1260 on. The default is to use the selected window's parameters.
1261
1262 Like `vertical-motion', `count-screen-lines' always uses the current
1263 buffer, regardless of which buffer is displayed in WINDOW. This makes
1264 possible to use `count-screen-lines' in any buffer, whether or not it
1265 is currently displayed in some window.
1266
1267 ** The new function `mapc' is like `mapcar' but doesn't collect the
1268 argument function's results.
1269
1270 ** The functions base64-decode-region and base64-decode-string now
1271 signal an error instead of returning nil if decoding fails.
1272
1273 ** The function sendmail-user-agent-compose now recognizes a `body'
1274 header is the list of headers passed to it.
1275
1276 ** The new function member-ignore-case works like `member', but
1277 ignores differences in case and text representation.
1278
1279 ** The buffer-local variable cursor-type can be used to specify the
1280 cursor to use in windows displaying a buffer. Values are interpreted
1281 as follows:
1282
1283 t use the cursor specified for the frame (default)
1284 nil don't display a cursor
1285 `bar' display a bar cursor with default width
1286 (bar . WIDTH) display a bar cursor with width WIDTH
1287 others display a box cursor.
1288
1289 ** The variable open-paren-in-column-0-is-defun-start controls whether
1290 an open parenthesis in column 0 is considered to be the start of a
1291 defun. If set, the default, it is considered a defun start. If not
1292 set, an open parenthesis in column 0 has no special meaning.
1293
1294 ** The new function `string-to-syntax' can be used to translate syntax
1295 specifications in string form as accepted by `modify-syntax-entry' to
1296 the cons-cell form that is used for the values of the `syntax-table'
1297 text property, and in `font-lock-syntactic-keywords'.
1298
1299 Example:
1300
1301 (string-to-syntax "()")
1302 => (4 . 41)
1303
1304 ** Emacs' reader supports CL read syntax for integers in bases
1305 other than 10.
1306
1307 *** `#BINTEGER' or `#bINTEGER' reads INTEGER in binary (radix 2).
1308 INTEGER optionally contains a sign.
1309
1310 #b1111
1311 => 15
1312 #b-1111
1313 => -15
1314
1315 *** `#OINTEGER' or `#oINTEGER' reads INTEGER in octal (radix 8).
1316
1317 #o666
1318 => 438
1319
1320 *** `#XINTEGER' or `#xINTEGER' reads INTEGER in hexadecimal (radix 16).
1321
1322 #xbeef
1323 => 48815
1324
1325 *** `#RADIXrINTEGER' reads INTEGER in radix RADIX, 2 <= RADIX <= 36.
1326
1327 #2R-111
1328 => -7
1329 #25rah
1330 => 267
1331
1332 ** The function `documentation-property' now evaluates the value of
1333 the given property to obtain a a string if it doesn't refer to etc/DOC
1334 and isn't a string.
1335
1336 ** If called for a symbol, the function `documentation' now looks for
1337 a `function-documentation' property of that symbol. If it has a non-nil
1338 value, the documentation is taken from that value. If the value is
1339 not a string, it is evaluated to obtain a string.
1340
1341 +++
1342 ** The last argument of `define-key-after' defaults to t for convenience.
1343
1344 ** The new function `replace-regexp-in-string' replaces all matches
1345 for a regexp in a string.
1346
1347 ** `mouse-position' now runs the abnormal hook
1348 `mouse-position-function'.
1349
1350 ** The function string-to-number now returns a float for numbers
1351 that don't fit into a Lisp integer.
1352
1353 ** The variable keyword-symbols-constants-flag has been removed.
1354 Keywords are now always considered constants.
1355
1356 +++
1357 ** The new function `delete-and-extract-region' deletes text and
1358 returns it.
1359
1360 ** The function `clear-this-command-keys' now also clears the vector
1361 returned by function `recent-keys'.
1362
1363 +++
1364 ** Variables `beginning-of-defun-function' and `end-of-defun-function'
1365 can be used to define handlers for the functions that find defuns.
1366 Major modes can define these locally instead of rebinding M-C-a
1367 etc. if the normal conventions for defuns are not appropriate for the
1368 mode.
1369
1370 +++
1371 ** easy-mmode-define-minor-mode now takes an additional BODY argument
1372 and is renamed `define-minor-mode'.
1373
1374 +++
1375 ** If an abbrev has a hook function which is a symbol, and that symbol
1376 has a non-nil `no-self-insert' property, the return value of the hook
1377 function specifies whether an expansion has been done or not. If it
1378 returns nil, abbrev-expand also returns nil, meaning "no expansion has
1379 been performed."
1380
1381 When abbrev expansion is done by typing a self-inserting character,
1382 and the abbrev has a hook with the `no-self-insert' property, and the
1383 hook function returns non-nil meaning expansion has been done,
1384 then the self-inserting character is not inserted.
1385
1386 +++
1387 ** The function `intern-soft' now accepts a symbol as first argument.
1388 In this case, that exact symbol is looked up in the specified obarray,
1389 and the function's value is nil if it is not found.
1390
1391 +++
1392 ** The new macro `with-syntax-table' can be used to evaluate forms
1393 with the syntax table of the current buffer temporarily set to a
1394 specified table.
1395
1396 (with-syntax-table TABLE &rest BODY)
1397
1398 Evaluate BODY with syntax table of current buffer set to a copy of
1399 TABLE. The current syntax table is saved, BODY is evaluated, and the
1400 saved table is restored, even in case of an abnormal exit. Value is
1401 what BODY returns.
1402
1403 +++
1404 ** Regular expressions now support intervals \{n,m\} as well as
1405 Perl's shy-groups \(?:...\) and non-greedy *? +? and ?? operators.
1406
1407 +++
1408 ** The optional argument BUFFER of function file-local-copy has been
1409 removed since it wasn't used by anything.
1410
1411 +++
1412 ** The file name argument of function `file-locked-p' is now required
1413 instead of being optional.
1414
1415 +++
1416 ** The new built-in error `text-read-only' is signaled when trying to
1417 modify read-only text.
1418
1419 +++
1420 ** New functions and variables for locales.
1421
1422 The new variable `locale-coding-system' specifies how to encode and
1423 decode strings passed to low-level message functions like strerror and
1424 time functions like strftime. The new variables
1425 `system-messages-locale' and `system-time-locale' give the system
1426 locales to be used when invoking these two types of functions.
1427
1428 The new function `set-locale-environment' sets the language
1429 environment, preferred coding system, and locale coding system from
1430 the system locale as specified by the LC_ALL, LC_CTYPE, and LANG
1431 environment variables. Normally, it is invoked during startup and need
1432 not be invoked thereafter. It uses the new variables
1433 `locale-language-names', `locale-charset-language-names', and
1434 `locale-preferred-coding-systems' to make its decisions.
1435
1436 +++
1437 ** syntax tables now understand nested comments.
1438 To declare a comment syntax as allowing nesting, just add an `n'
1439 modifier to either of the characters of the comment end and the comment
1440 start sequences.
1441
1442 +++
1443 ** The function `pixmap-spec-p' has been renamed `bitmap-spec-p'
1444 because `bitmap' is more in line with the usual X terminology.
1445
1446 +++
1447 ** New function `propertize'
1448
1449 The new function `propertize' can be used to conveniently construct
1450 strings with text properties.
1451
1452 - Function: propertize STRING &rest PROPERTIES
1453
1454 Value is a copy of STRING with text properties assigned as specified
1455 by PROPERTIES. PROPERTIES is a sequence of pairs PROPERTY VALUE, with
1456 PROPERTY being the name of a text property and VALUE being the
1457 specified value of that property. Example:
1458
1459 (propertize "foo" 'face 'bold 'read-only t)
1460
1461 +++
1462 ** push and pop macros.
1463
1464 Simple versions of the push and pop macros of Common Lisp
1465 are now defined in Emacs Lisp. These macros allow only symbols
1466 as the place that holds the list to be changed.
1467
1468 (push NEWELT LISTNAME) add NEWELT to the front of LISTNAME's value.
1469 (pop LISTNAME) return first elt of LISTNAME, and remove it
1470 (thus altering the value of LISTNAME).
1471
1472 ** New dolist and dotimes macros.
1473
1474 Simple versions of the dolist and dotimes macros of Common Lisp
1475 are now defined in Emacs Lisp.
1476
1477 (dolist (VAR LIST [RESULT]) BODY...)
1478 Execute body once for each element of LIST,
1479 using the variable VAR to hold the current element.
1480 Then return the value of RESULT, or nil if RESULT is omitted.
1481
1482 (dotimes (VAR COUNT [RESULT]) BODY...)
1483 Execute BODY with VAR bound to successive integers running from 0,
1484 inclusive, to COUNT, exclusive.
1485 Then return the value of RESULT, or nil if RESULT is omitted.
1486
1487 +++
1488 ** Regular expressions now support Posix character classes such
1489 as [:alpha:], [:space:] and so on.
1490
1491 [:digit:] matches 0 through 9
1492 [:cntrl:] matches ASCII control characters
1493 [:xdigit:] matches 0 through 9, a through f and A through F.
1494 [:blank:] matches space and tab only
1495 [:graph:] matches graphic characters--everything except ASCII control chars,
1496 space, and DEL.
1497 [:print:] matches printing characters--everything except ASCII control chars
1498 and DEL.
1499 [:alnum:] matches letters and digits.
1500 (But at present, for multibyte characters,
1501 it matches anything that has word syntax.)
1502 [:alpha:] matches letters.
1503 (But at present, for multibyte characters,
1504 it matches anything that has word syntax.)
1505 [:ascii:] matches ASCII (unibyte) characters.
1506 [:nonascii:] matches non-ASCII (multibyte) characters.
1507 [:lower:] matches anything lower-case.
1508 [:punct:] matches punctuation.
1509 (But at present, for multibyte characters,
1510 it matches anything that has non-word syntax.)
1511 [:space:] matches anything that has whitespace syntax.
1512 [:upper:] matches anything upper-case.
1513 [:word:] matches anything that has word syntax.
1514
1515 +++
1516 ** Emacs now has built-in hash tables.
1517
1518 The following functions are defined for hash tables:
1519
1520 - Function: make-hash-table ARGS
1521
1522 The argument list ARGS consists of keyword/argument pairs. All arguments
1523 are optional. The following arguments are defined:
1524
1525 :test TEST
1526
1527 TEST must be a symbol specifying how to compare keys. Default is `eql'.
1528 Predefined are `eq', `eql' and `equal'. If TEST is not predefined,
1529 it must have been defined with `define-hash-table-test'.
1530
1531 :size SIZE
1532
1533 SIZE must be an integer > 0 giving a hint to the implementation how
1534 many elements will be put in the hash table. Default size is 65.
1535
1536 :rehash-size REHASH-SIZE
1537
1538 REHASH-SIZE specifies by how much to grow a hash table once it becomes
1539 full. If REHASH-SIZE is an integer, add that to the hash table's old
1540 size to get the new size. Otherwise, REHASH-SIZE must be a float >
1541 1.0, and the new size is computed by multiplying REHASH-SIZE with the
1542 old size. Default rehash size is 1.5.
1543
1544 :rehash-threshold THRESHOLD
1545
1546 THRESHOLD must be a float > 0 and <= 1.0 specifying when to resize the
1547 hash table. It is resized when the ratio of (number of entries) /
1548 (size of hash table) is >= THRESHOLD. Default threshold is 0.8.
1549
1550 :weakness WEAK
1551
1552 WEAK must be either nil, one of the symbols `key, `value', or t.
1553 Entries are removed from weak tables during garbage collection if
1554 their key and/or value are not referenced elsewhere outside of the
1555 hash table. Default are non-weak hash tables.
1556
1557 - Function: makehash &optional TEST
1558
1559 Similar to make-hash-table, but only TEST can be specified.
1560
1561 - Function: hash-table-p TABLE
1562
1563 Returns non-nil if TABLE is a hash table object.
1564
1565 - Function: copy-hash-table TABLE
1566
1567 Returns a copy of TABLE. Only the table itself is copied, keys and
1568 values are shared.
1569
1570 - Function: hash-table-count TABLE
1571
1572 Returns the number of entries in TABLE.
1573
1574 - Function: hash-table-rehash-size TABLE
1575
1576 Returns the rehash size of TABLE.
1577
1578 - Function: hash-table-rehash-threshold TABLE
1579
1580 Returns the rehash threshold of TABLE.
1581
1582 - Function: hash-table-rehash-size TABLE
1583
1584 Returns the size of TABLE.
1585
1586 - Function: hash-table-rehash-test TABLE
1587
1588 Returns the test TABLE uses to compare keys.
1589
1590 - Function: hash-table-weakness TABLE
1591
1592 Returns the weakness specified for TABLE.
1593
1594 - Function: clrhash TABLE
1595
1596 Clear TABLE.
1597
1598 - Function: gethash KEY TABLE &optional DEFAULT
1599
1600 Look up KEY in TABLE and return its associated VALUE or DEFAULT if
1601 not found.
1602
1603 - Function: puthash KEY VALUE TABLE
1604
1605 Associate KEY with VALUE in TABLE. If KEY is already associated with
1606 another value, replace the old value with VALUE.
1607
1608 - Function: remhash KEY TABLE
1609
1610 Remove KEY from TABLE if it is there.
1611
1612 - Function: maphash FUNCTION TABLE
1613
1614 Call FUNCTION for all elements in TABLE. FUNCTION must take two
1615 arguments KEY and VALUE.
1616
1617 - Function: sxhash OBJ
1618
1619 Return a hash code for Lisp object OBJ.
1620
1621 - Function: define-hash-table-test NAME TEST-FN HASH-FN
1622
1623 Define a new hash table test named NAME. If NAME is specified as
1624 a test in `make-hash-table', the table created will use TEST-FN for
1625 comparing keys, and HASH-FN to compute hash codes for keys. Test
1626 and hash function are stored as symbol property `hash-table-test'
1627 of NAME with a value of (TEST-FN HASH-FN).
1628
1629 TEST-FN must take two arguments and return non-nil if they are the same.
1630
1631 HASH-FN must take one argument and return an integer that is the hash
1632 code of the argument. The function should use the whole range of
1633 integer values for hash code computation, including negative integers.
1634
1635 Example: The following creates a hash table whose keys are supposed to
1636 be strings that are compared case-insensitively.
1637
1638 (defun case-fold-string= (a b)
1639 (compare-strings a nil nil b nil nil t))
1640
1641 (defun case-fold-string-hash (a)
1642 (sxhash (upcase a)))
1643
1644 (define-hash-table-test 'case-fold 'case-fold-string=
1645 'case-fold-string-hash))
1646
1647 (make-hash-table :test 'case-fold)
1648
1649 +++
1650 ** The Lisp reader handles circular structure.
1651
1652 It now works to use the #N= and #N# constructs to represent
1653 circular structures. For example, #1=(a . #1#) represents
1654 a cons cell which is its own cdr.
1655
1656 +++
1657 ** The Lisp printer handles circular structure.
1658
1659 If you bind print-circle to a non-nil value, the Lisp printer outputs
1660 #N= and #N# constructs to represent circular and shared structure.
1661
1662 +++
1663 ** If the second argument to `move-to-column' is anything but nil or
1664 t, that means replace a tab with spaces if necessary to reach the
1665 specified column, but do not add spaces at the end of the line if it
1666 is too short to reach that column.
1667
1668 +++
1669 ** perform-replace has a new feature: the REPLACEMENTS argument may
1670 now be a cons cell (FUNCTION . DATA). This means to call FUNCTION
1671 after each match to get the replacement text. FUNCTION is called with
1672 two arguments: DATA, and the number of replacements already made.
1673
1674 If the FROM-STRING contains any upper-case letters,
1675 perform-replace also turns off `case-fold-search' temporarily
1676 and inserts the replacement text without altering case in it.
1677
1678 +++
1679 ** The function buffer-size now accepts an optional argument
1680 to specify which buffer to return the size of.
1681
1682 +++
1683 ** The calendar motion commands now run the normal hook
1684 calendar-move-hook after moving point.
1685
1686 +++
1687 ** The new variable small-temporary-file-directory specifies a
1688 directory to use for creating temporary files that are likely to be
1689 small. (Certain Emacs features use this directory.) If
1690 small-temporary-file-directory is nil, they use
1691 temporary-file-directory instead.
1692
1693 +++
1694 ** The variable `inhibit-modification-hooks', if non-nil, inhibits all
1695 the hooks that track changes in the buffer. This affects
1696 `before-change-functions' and `after-change-functions', as well as
1697 hooks attached to text properties and overlay properties.
1698
1699 +++
1700 ** assoc-delete-all is a new function that deletes all the
1701 elements of an alist which have a particular value as the car.
1702
1703 +++
1704 ** make-temp-file provides a more reliable way to create a temporary file.
1705
1706 make-temp-file is used like make-temp-name, except that it actually
1707 creates the file before it returns. This prevents a timing error,
1708 ensuring that no other job can use the same name for a temporary file.
1709
1710 +++
1711 ** New exclusive-open feature in `write-region'
1712
1713 The optional seventh arg is now called MUSTBENEW. If non-nil, it insists
1714 on a check for an existing file with the same name. If MUSTBENEW
1715 is `excl', that means to get an error if the file already exists;
1716 never overwrite. If MUSTBENEW is neither nil nor `excl', that means
1717 ask for confirmation before overwriting, but do go ahead and
1718 overwrite the file if the user gives confirmation.
1719
1720 If the MUSTBENEW argument in `write-region' is `excl',
1721 that means to use a special feature in the `open' system call
1722 to get an error if the file exists at that time.
1723 The error reported is `file-already-exists'.
1724
1725 +++
1726 ** Function `format' now handles text properties.
1727
1728 Text properties of the format string are applied to the result string.
1729 If the result string is longer than the format string, text properties
1730 ending at the end of the format string are extended to the end of the
1731 result string.
1732
1733 Text properties from string arguments are applied to the result
1734 string where arguments appear in the result string.
1735
1736 Example:
1737
1738 (let ((s1 "hello, %s")
1739 (s2 "world"))
1740 (put-text-property 0 (length s1) 'face 'bold s1)
1741 (put-text-property 0 (length s2) 'face 'italic s2)
1742 (format s1 s2))
1743
1744 results in a bold-face string with an italic `world' at the end.
1745
1746 +++
1747 ** Messages can now be displayed with text properties.
1748
1749 Text properties are handled as described above for function `format'.
1750 The following example displays a bold-face message with an italic
1751 argument in it.
1752
1753 (let ((msg "hello, %s!")
1754 (arg "world"))
1755 (put-text-property 0 (length msg) 'face 'bold msg)
1756 (put-text-property 0 (length arg) 'face 'italic arg)
1757 (message msg arg))
1758
1759 +++
1760 ** Sound support
1761
1762 Emacs supports playing sound files on GNU/Linux and the free BSDs
1763 (Voxware driver and native BSD driver, aka as Luigi's driver).
1764
1765 Currently supported file formats are RIFF-WAVE (*.wav) and Sun Audio
1766 (*.au). You must configure Emacs with the option `--with-sound=yes'
1767 to enable sound support.
1768
1769 Sound files can be played by calling (play-sound SOUND). SOUND is a
1770 list of the form `(sound PROPERTY...)'. The function is only defined
1771 when sound support is present for the system on which Emacs runs. The
1772 functions runs `play-sound-functions' with one argument which is the
1773 sound to play, before playing the sound.
1774
1775 The following sound properties are supported:
1776
1777 - `:file FILE'
1778
1779 FILE is a file name. If FILE isn't an absolute name, it will be
1780 searched relative to `data-directory'.
1781
1782 - `:data DATA'
1783
1784 DATA is a string containing sound data. Either :file or :data
1785 may be present, but not both.
1786
1787 - `:volume VOLUME'
1788
1789 VOLUME must be an integer in the range 0..100 or a float in the range
1790 0..1. This property is optional.
1791
1792 Other properties are ignored.
1793
1794 ** `multimedia' is a new Finder keyword and Custom group.
1795
1796 ** keywordp is a new predicate to test efficiently for an object being
1797 a keyword symbol.
1798
1799 ** Changes to garbage collection
1800
1801 *** The function garbage-collect now additionally returns the number
1802 of live and free strings.
1803
1804 *** There is a new variable `strings-consed' holding the number of
1805 strings that have been consed so far.
1806
1807 \f
1808 * Lisp-level Display features added after release 2.6 of the Emacs
1809 Lisp Manual
1810
1811 ** Image specifications may contain the property `:ascent center'.
1812
1813 When this property is specified, the image is vertically centered
1814 around a centerline which would be the vertical center of text drawn
1815 at the position of the image, in the manner specified by the text
1816 properties and overlays that apply to the image.
1817
1818 \f
1819 * New Lisp-level Display features in Emacs 21.1
1820
1821 Note that +++ before an item means the Lisp manual has been updated.
1822 --- means that I have decided it does not need to be in the Lisp manual.
1823 When you add a new item, please add it without either +++ or ---
1824 so I will know I still need to look at it -- rms.
1825
1826 ** The function tty-suppress-bold-inverse-default-colors can be used
1827 to make Emacs avoid displaying text with bold black foreground on TTYs.
1828
1829 Some terminals, notably PC consoles, emulate bold text by displaying
1830 text in brighter colors. On such a console, a bold black foreground
1831 is displayed in a gray color. If this turns out to be hard to read on
1832 your monitor---the problem occurred with the mode line on
1833 laptops---you can instruct Emacs to ignore the text's boldness, and to
1834 just display it black instead.
1835
1836 This situation can't be detected automatically. You will have to put
1837 a line like
1838
1839 (tty-suppress-bold-inverse-default-colors t)
1840
1841 in your `.emacs'.
1842
1843 ** New face implementation.
1844
1845 Emacs faces have been reimplemented from scratch. They don't use XLFD
1846 font names anymore and face merging now works as expected.
1847
1848 +++
1849 *** New faces.
1850
1851 Each face can specify the following display attributes:
1852
1853 1. Font family or fontset alias name.
1854
1855 2. Relative proportionate width, aka character set width or set
1856 width (swidth), e.g. `semi-compressed'.
1857
1858 3. Font height in 1/10pt
1859
1860 4. Font weight, e.g. `bold'.
1861
1862 5. Font slant, e.g. `italic'.
1863
1864 6. Foreground color.
1865
1866 7. Background color.
1867
1868 8. Whether or not characters should be underlined, and in what color.
1869
1870 9. Whether or not characters should be displayed in inverse video.
1871
1872 10. A background stipple, a bitmap.
1873
1874 11. Whether or not characters should be overlined, and in what color.
1875
1876 12. Whether or not characters should be strike-through, and in what
1877 color.
1878
1879 13. Whether or not a box should be drawn around characters, its
1880 color, the width of the box lines, and 3D appearance.
1881
1882 Faces are frame-local by nature because Emacs allows to define the
1883 same named face (face names are symbols) differently for different
1884 frames. Each frame has an alist of face definitions for all named
1885 faces. The value of a named face in such an alist is a Lisp vector
1886 with the symbol `face' in slot 0, and a slot for each each of the face
1887 attributes mentioned above.
1888
1889 There is also a global face alist `face-new-frame-defaults'. Face
1890 definitions from this list are used to initialize faces of newly
1891 created frames.
1892
1893 A face doesn't have to specify all attributes. Those not specified
1894 have a nil value. Faces specifying all attributes are called
1895 `fully-specified'.
1896
1897 +++
1898 *** Face merging.
1899
1900 The display style of a given character in the text is determined by
1901 combining several faces. This process is called `face merging'. Any
1902 aspect of the display style that isn't specified by overlays or text
1903 properties is taken from the `default' face. Since it is made sure
1904 that the default face is always fully-specified, face merging always
1905 results in a fully-specified face.
1906
1907 +++
1908 *** Face realization.
1909
1910 After all face attributes for a character have been determined by
1911 merging faces of that character, that face is `realized'. The
1912 realization process maps face attributes to what is physically
1913 available on the system where Emacs runs. The result is a `realized
1914 face' in form of an internal structure which is stored in the face
1915 cache of the frame on which it was realized.
1916
1917 Face realization is done in the context of the charset of the
1918 character to display because different fonts and encodings are used
1919 for different charsets. In other words, for characters of different
1920 charsets, different realized faces are needed to display them.
1921
1922 Except for composite characters, faces are always realized for a
1923 specific character set and contain a specific font, even if the face
1924 being realized specifies a fontset. The reason is that the result of
1925 the new font selection stage is better than what can be done with
1926 statically defined font name patterns in fontsets.
1927
1928 In unibyte text, Emacs' charsets aren't applicable; function
1929 `char-charset' reports ASCII for all characters, including those >
1930 0x7f. The X registry and encoding of fonts to use is determined from
1931 the variable `face-default-registry' in this case. The variable is
1932 initialized at Emacs startup time from the font the user specified for
1933 Emacs.
1934
1935 Currently all unibyte text, i.e. all buffers with
1936 `enable-multibyte-characters' nil are displayed with fonts of the same
1937 registry and encoding `face-default-registry'. This is consistent
1938 with the fact that languages can also be set globally, only.
1939
1940 ++++
1941 **** Clearing face caches.
1942
1943 The Lisp function `clear-face-cache' can be called to clear face caches
1944 on all frames. If called with a non-nil argument, it will also unload
1945 unused fonts.
1946
1947 +++
1948 *** Font selection.
1949
1950 Font selection tries to find the best available matching font for a
1951 given (charset, face) combination. This is done slightly differently
1952 for faces specifying a fontset, or a font family name.
1953
1954 If the face specifies a fontset name, that fontset determines a
1955 pattern for fonts of the given charset. If the face specifies a font
1956 family, a font pattern is constructed. Charset symbols have a
1957 property `x-charset-registry' for that purpose that maps a charset to
1958 an XLFD registry and encoding in the font pattern constructed.
1959
1960 Available fonts on the system on which Emacs runs are then matched
1961 against the font pattern. The result of font selection is the best
1962 match for the given face attributes in this font list.
1963
1964 Font selection can be influenced by the user.
1965
1966 The user can specify the relative importance he gives the face
1967 attributes width, height, weight, and slant by setting
1968 face-font-selection-order (faces.el) to a list of face attribute
1969 names. The default is (:width :height :weight :slant), and means
1970 that font selection first tries to find a good match for the font
1971 width specified by a face, then---within fonts with that width---tries
1972 to find a best match for the specified font height, etc.
1973
1974 Setting `face-alternative-font-family-alist' allows the user to
1975 specify alternative font families to try if a family specified by a
1976 face doesn't exist.
1977
1978 +++
1979 **** Scalable fonts
1980
1981 Emacs can make use of scalable fonts but doesn't do so by default,
1982 since the use of too many or too big scalable fonts may crash XFree86
1983 servers.
1984
1985 To enable scalable font use, set the variable
1986 `scalable-fonts-allowed'. A value of nil, the default, means never use
1987 scalable fonts. A value of t means any scalable font may be used.
1988 Otherwise, the value must be a list of regular expressions. A
1989 scalable font may then be used if it matches a regular expression from
1990 that list. Example:
1991
1992 (setq scalable-fonts-allowed '("muleindian-2$"))
1993
1994 allows the use of scalable fonts with registry `muleindian-2'.
1995
1996 +++
1997 *** Functions and variables related to font selection.
1998
1999 - Function: x-family-fonts &optional FAMILY FRAME
2000
2001 Return a list of available fonts of family FAMILY on FRAME. If FAMILY
2002 is omitted or nil, list all families. Otherwise, FAMILY must be a
2003 string, possibly containing wildcards `?' and `*'.
2004
2005 If FRAME is omitted or nil, use the selected frame. Each element of
2006 the result is a vector [FAMILY WIDTH POINT-SIZE WEIGHT SLANT FIXED-P
2007 FULL REGISTRY-AND-ENCODING]. FAMILY is the font family name.
2008 POINT-SIZE is the size of the font in 1/10 pt. WIDTH, WEIGHT, and
2009 SLANT are symbols describing the width, weight and slant of the font.
2010 These symbols are the same as for face attributes. FIXED-P is non-nil
2011 if the font is fixed-pitch. FULL is the full name of the font, and
2012 REGISTRY-AND-ENCODING is a string giving the registry and encoding of
2013 the font. The result list is sorted according to the current setting
2014 of the face font sort order.
2015
2016 - Function: x-font-family-list
2017
2018 Return a list of available font families on FRAME. If FRAME is
2019 omitted or nil, use the selected frame. Value is a list of conses
2020 (FAMILY . FIXED-P) where FAMILY is a font family, and FIXED-P is
2021 non-nil if fonts of that family are fixed-pitch.
2022
2023 - Variable: font-list-limit
2024
2025 Limit for font matching. If an integer > 0, font matching functions
2026 won't load more than that number of fonts when searching for a
2027 matching font. The default is currently 100.
2028
2029 +++
2030 *** Setting face attributes.
2031
2032 For the most part, the new face implementation is interface-compatible
2033 with the old one. Old face attribute related functions are now
2034 implemented in terms of the new functions `set-face-attribute' and
2035 `face-attribute'.
2036
2037 Face attributes are identified by their names which are keyword
2038 symbols. All attributes can be set to `unspecified'.
2039
2040 The following attributes are recognized:
2041
2042 `:family'
2043
2044 VALUE must be a string specifying the font family, e.g. ``courier'',
2045 or a fontset alias name. If a font family is specified, wild-cards `*'
2046 and `?' are allowed.
2047
2048 `:width'
2049
2050 VALUE specifies the relative proportionate width of the font to use.
2051 It must be one of the symbols `ultra-condensed', `extra-condensed',
2052 `condensed', `semi-condensed', `normal', `semi-expanded', `expanded',
2053 `extra-expanded', or `ultra-expanded'.
2054
2055 `:height'
2056
2057 VALUE must be an integer specifying the height of the font to use in
2058 1/10 pt.
2059
2060 `:weight'
2061
2062 VALUE specifies the weight of the font to use. It must be one of the
2063 symbols `ultra-bold', `extra-bold', `bold', `semi-bold', `normal',
2064 `semi-light', `light', `extra-light', `ultra-light'.
2065
2066 `:slant'
2067
2068 VALUE specifies the slant of the font to use. It must be one of the
2069 symbols `italic', `oblique', `normal', `reverse-italic', or
2070 `reverse-oblique'.
2071
2072 `:foreground', `:background'
2073
2074 VALUE must be a color name, a string.
2075
2076 `:underline'
2077
2078 VALUE specifies whether characters in FACE should be underlined. If
2079 VALUE is t, underline with foreground color of the face. If VALUE is
2080 a string, underline with that color. If VALUE is nil, explicitly
2081 don't underline.
2082
2083 `:overline'
2084
2085 VALUE specifies whether characters in FACE should be overlined. If
2086 VALUE is t, overline with foreground color of the face. If VALUE is a
2087 string, overline with that color. If VALUE is nil, explicitly don't
2088 overline.
2089
2090 `:strike-through'
2091
2092 VALUE specifies whether characters in FACE should be drawn with a line
2093 striking through them. If VALUE is t, use the foreground color of the
2094 face. If VALUE is a string, strike-through with that color. If VALUE
2095 is nil, explicitly don't strike through.
2096
2097 `:box'
2098
2099 VALUE specifies whether characters in FACE should have a box drawn
2100 around them. If VALUE is nil, explicitly don't draw boxes. If
2101 VALUE is t, draw a box with lines of width 1 in the foreground color
2102 of the face. If VALUE is a string, the string must be a color name,
2103 and the box is drawn in that color with a line width of 1. Otherwise,
2104 VALUE must be a property list of the form `(:line-width WIDTH
2105 :color COLOR :style STYLE)'. If a keyword/value pair is missing from
2106 the property list, a default value will be used for the value, as
2107 specified below. WIDTH specifies the width of the lines to draw; it
2108 defaults to 1. COLOR is the name of the color to draw in, default is
2109 the foreground color of the face for simple boxes, and the background
2110 color of the face for 3D boxes. STYLE specifies whether a 3D box
2111 should be draw. If STYLE is `released-button', draw a box looking
2112 like a released 3D button. If STYLE is `pressed-button' draw a box
2113 that appears like a pressed button. If STYLE is nil, the default if
2114 the property list doesn't contain a style specification, draw a 2D
2115 box.
2116
2117 `:inverse-video'
2118
2119 VALUE specifies whether characters in FACE should be displayed in
2120 inverse video. VALUE must be one of t or nil.
2121
2122 `:stipple'
2123
2124 If VALUE is a string, it must be the name of a file of pixmap data.
2125 The directories listed in the `x-bitmap-file-path' variable are
2126 searched. Alternatively, VALUE may be a list of the form (WIDTH
2127 HEIGHT DATA) where WIDTH and HEIGHT are the size in pixels, and DATA
2128 is a string containing the raw bits of the bitmap. VALUE nil means
2129 explicitly don't use a stipple pattern.
2130
2131 For convenience, attributes `:family', `:width', `:height', `:weight',
2132 and `:slant' may also be set in one step from an X font name:
2133
2134 `:font'
2135
2136 Set font-related face attributes from VALUE. VALUE must be a valid
2137 XLFD font name. If it is a font name pattern, the first matching font
2138 is used--this is for compatibility with the behavior of previous
2139 versions of Emacs.
2140
2141 For compatibility with Emacs 20, keywords `:bold' and `:italic' can
2142 be used to specify that a bold or italic font should be used. VALUE
2143 must be t or nil in that case. A value of `unspecified' is not allowed."
2144
2145 Please see also the documentation of `set-face-attribute' and
2146 `defface'.
2147
2148 *** Face attributes and X resources
2149
2150 The following X resource names can be used to set face attributes
2151 from X resources:
2152
2153 Face attribute X resource class
2154 -----------------------------------------------------------------------
2155 :family attributeFamily . Face.AttributeFamily
2156 :width attributeWidth Face.AttributeWidth
2157 :height attributeHeight Face.AttributeHeight
2158 :weight attributeWeight Face.AttributeWeight
2159 :slant attributeSlant Face.AttributeSlant
2160 foreground attributeForeground Face.AttributeForeground
2161 :background attributeBackground . Face.AttributeBackground
2162 :overline attributeOverline Face.AttributeOverline
2163 :strike-through attributeStrikeThrough Face.AttributeStrikeThrough
2164 :box attributeBox Face.AttributeBox
2165 :underline attributeUnderline Face.AttributeUnderline
2166 :inverse-video attributeInverse Face.AttributeInverse
2167 :stipple attributeStipple Face.AttributeStipple
2168 or attributeBackgroundPixmap
2169 Face.AttributeBackgroundPixmap
2170 :font attributeFont Face.AttributeFont
2171 :bold attributeBold Face.AttributeBold
2172 :italic attributeItalic . Face.AttributeItalic
2173 :font attributeFont Face.AttributeFont
2174
2175 +++
2176 *** Text property `face'.
2177
2178 The value of the `face' text property can now be a single face
2179 specification or a list of such specifications. Each face
2180 specification can be
2181
2182 1. A symbol or string naming a Lisp face.
2183
2184 2. A property list of the form (KEYWORD VALUE ...) where each
2185 KEYWORD is a face attribute name, and VALUE is an appropriate value
2186 for that attribute. Please see the doc string of `set-face-attribute'
2187 for face attribute names.
2188
2189 3. Conses of the form (FOREGROUND-COLOR . COLOR) or
2190 (BACKGROUND-COLOR . COLOR) where COLOR is a color name. This is
2191 for compatibility with previous Emacs versions.
2192
2193 +++
2194 ** Support functions for colors on text-only terminals.
2195
2196 The function `tty-color-define' can be used to define colors for use
2197 on TTY and MSDOS frames. It maps a color name to a color number on
2198 the terminal. Emacs defines a couple of common color mappings by
2199 default. You can get defined colors with a call to
2200 `defined-colors'. The function `tty-color-clear' can be
2201 used to clear the mapping table.
2202
2203 ** Unified support for colors independent of frame type.
2204
2205 The new functions `defined-colors', `color-defined-p', `color-values',
2206 and `display-color-p' work for any type of frame. On frames whose
2207 type is neither x nor w32, these functions transparently map X-style
2208 color specifications to the closest colors supported by the frame
2209 display. Lisp programs should use these new functions instead of the
2210 old `x-defined-colors', `x-color-defined-p', `x-color-values', and
2211 `x-display-color-p'. (The old function names are still available for
2212 compatibility; they are now aliases of the new names.) Lisp programs
2213 should no more look at the value of the variable window-system to
2214 modify their color-related behavior.
2215
2216 The primitives `color-gray-p' and `color-supported-p' also work for
2217 any frame type.
2218
2219 ** Platform-independent functions to describe display capabilities.
2220
2221 The new functions `display-mouse-p', `display-popup-menus-p',
2222 `display-graphic-p', `display-selections-p', `display-screens',
2223 `display-pixel-width', `display-pixel-height', `display-mm-width',
2224 `display-mm-height', `display-backing-store', `display-save-under',
2225 `display-planes', `display-color-cells', `display-visual-class', and
2226 `display-grayscale-p' describe the basic capabilities of a particular
2227 display. Lisp programs should call these functions instead of testing
2228 the value of the variables `window-system' or `system-type', or calling
2229 platform-specific functions such as `x-display-pixel-width'.
2230
2231 +++
2232 ** The minibuffer prompt is now actually inserted in the minibuffer.
2233
2234 This makes it possible to scroll through the prompt, if you want to.
2235
2236 The function minubuffer-prompt-end returns the current position of the
2237 end of the minibuffer prompt, if the minibuffer is current.
2238 Otherwise, it returns zero.
2239
2240 ** New `field' abstraction in buffers.
2241
2242 There is now code to support an abstraction called `fields' in emacs
2243 buffers. A field is a contiguous region of text with the same `field'
2244 text-property.
2245
2246 Many emacs functions, such as forward-word, forward-sentence,
2247 forward-paragraph, beginning-of-line, etc., stop moving when they come
2248 to the boundary between fields; beginning-of-line and end-of-line will
2249 not let the point move past the field boundary, but other movement
2250 commands continue into the next field if repeated. Stopping at field
2251 boundaries can be suppressed programmatically by binding
2252 `inhibit-field-text-motion' to a non-nil value around calls to these
2253 functions.
2254
2255 Now that the minibuffer prompt is inserted into the minibuffer, it is in
2256 a separate field from the user-input part of the buffer, so that common
2257 editing commands treat the user's text separately from the prompt.
2258
2259 The following functions are defined for operating on fields:
2260
2261 - Function: constrain-to-field NEW-POS OLD-POS &optional ESCAPE-FROM-EDGE ONLY-IN-LINE
2262
2263 Return the position closest to NEW-POS that is in the same field as OLD-POS.
2264 A field is a region of text with the same `field' property.
2265 If NEW-POS is nil, then the current point is used instead, and set to the
2266 constrained position if that is is different.
2267
2268 If OLD-POS is at the boundary of two fields, then the allowable
2269 positions for NEW-POS depends on the value of the optional argument
2270 ESCAPE-FROM-EDGE: If ESCAPE-FROM-EDGE is nil, then NEW-POS is
2271 constrained to the field that has the same `field' text-property
2272 as any new characters inserted at OLD-POS, whereas if ESCAPE-FROM-EDGE
2273 is non-nil, NEW-POS is constrained to the union of the two adjacent
2274 fields.
2275
2276 If the optional argument ONLY-IN-LINE is non-nil and constraining
2277 NEW-POS would move it to a different line, NEW-POS is returned
2278 unconstrained. This useful for commands that move by line, like
2279 C-n or C-a, which should generally respect field boundaries
2280 only in the case where they can still move to the right line.
2281
2282 - Function: erase-field &optional POS
2283
2284 Erases the field surrounding POS.
2285 A field is a region of text with the same `field' property.
2286 If POS is nil, the position of the current buffer's point is used.
2287
2288 - Function: field-beginning &optional POS ESCAPE-FROM-EDGE
2289
2290 Return the beginning of the field surrounding POS.
2291 A field is a region of text with the same `field' property.
2292 If POS is nil, the position of the current buffer's point is used.
2293 If ESCAPE-FROM-EDGE is non-nil and POS is already at beginning of an
2294 field, then the beginning of the *previous* field is returned.
2295
2296 - Function: field-end &optional POS ESCAPE-FROM-EDGE
2297
2298 Return the end of the field surrounding POS.
2299 A field is a region of text with the same `field' property.
2300 If POS is nil, the position of the current buffer's point is used.
2301 If ESCAPE-FROM-EDGE is non-nil and POS is already at end of a field,
2302 then the end of the *following* field is returned.
2303
2304 - Function: field-string &optional POS
2305
2306 Return the contents of the field surrounding POS as a string.
2307 A field is a region of text with the same `field' property.
2308 If POS is nil, the position of the current buffer's point is used.
2309
2310 - Function: field-string-no-properties &optional POS
2311
2312 Return the contents of the field around POS, without text-properties.
2313 A field is a region of text with the same `field' property.
2314 If POS is nil, the position of the current buffer's point is used.
2315
2316 +++
2317 ** Image support.
2318
2319 Emacs can now display images. Images are inserted into text by giving
2320 strings or buffer text a `display' text property containing one of
2321 (AREA IMAGE) or IMAGE. The display of the `display' property value
2322 replaces the display of the characters having that property.
2323
2324 If the property value has the form (AREA IMAGE), AREA must be one of
2325 `(margin left-margin)', `(margin right-margin)' or `(margin nil)'. If
2326 AREA is `(margin nil)', IMAGE will be displayed in the text area of a
2327 window, otherwise it will be displayed in the left or right marginal
2328 area.
2329
2330 IMAGE is an image specification.
2331
2332 *** Image specifications
2333
2334 Image specifications are lists of the form `(image PROPS)' where PROPS
2335 is a property list whose keys are keyword symbols. Each
2336 specifications must contain a property `:type TYPE' with TYPE being a
2337 symbol specifying the image type, e.g. `xbm'. Properties not
2338 described below are ignored.
2339
2340 The following is a list of properties all image types share.
2341
2342 `:ascent ASCENT'
2343
2344 ASCENT must be a number in the range 0..100, or the symbol `center'.
2345 If it is a number, it specifies the percentage of the image's height
2346 to use for its ascent.
2347
2348 If not specified, ASCENT defaults to the value 50 which means that the
2349 image will be centered with the base line of the row it appears in.
2350
2351 If ASCENT is `center' the image is vertically centered around a
2352 centerline which is the vertical center of text drawn at the position
2353 of the image, in the manner specified by the text properties and
2354 overlays that apply to the image.
2355
2356 `:margin MARGIN'
2357
2358 MARGIN must be a number >= 0 specifying how many pixels to put as
2359 margin around the image. Default is 0.
2360
2361 `:relief RELIEF'
2362
2363 RELIEF is analogous to the `:relief' attribute of faces. Puts a relief
2364 around an image.
2365
2366 `:algorithm ALGO'
2367
2368 Apply an image algorithm to the image before displaying it. ALGO must
2369 be a symbol specifying the algorithm. Currently only `laplace' is
2370 supported which applies a Laplace edge detection algorithm to an image
2371 which is intended to display images "disabled."
2372
2373 `:heuristic-mask BG'
2374
2375 If BG is not nil, build a clipping mask for the image, so that the
2376 background of a frame is visible behind the image. If BG is t,
2377 determine the background color of the image by looking at the 4
2378 corners of the image, assuming the most frequently occuring color from
2379 the corners is the background color of the image. Otherwise, BG must
2380 be a list `(RED GREEN BLUE)' specifying the color to assume for the
2381 background of the image.
2382
2383 `:file FILE'
2384
2385 Load image from FILE. If FILE is not absolute after expanding it,
2386 search for the image in `data-directory'. Some image types support
2387 building images from data. When this is done, no `:file' property
2388 may be present in the image specification.
2389
2390 `:data DATA'
2391
2392 Get image data from DATA. (As of this writing, this is not yet
2393 supported for image type `postscript'). Either :file or :data may be
2394 present in an image specification, but not both. All image types
2395 support strings as DATA, some types allow additional types of DATA.
2396
2397 *** Supported image types
2398
2399 **** XBM, image type `xbm'.
2400
2401 XBM images don't require an external library. Additional image
2402 properties supported are
2403
2404 `:foreground FG'
2405
2406 FG must be a string specifying the image foreground color. Default
2407 is the frame's foreground.
2408
2409 `:background FG'
2410
2411 BG must be a string specifying the image foreground color. Default is
2412 the frame's background color.
2413
2414 XBM images can be constructed from data instead of file. In this
2415 case, the image specification must contain the following properties
2416 instead of a `:file' property.
2417
2418 `:width WIDTH'
2419
2420 WIDTH specifies the width of the image in pixels.
2421
2422 `:height HEIGHT'
2423
2424 HEIGHT specifies the height of the image in pixels.
2425
2426 `:data DATA'
2427
2428 DATA must be either
2429
2430 1. a string large enough to hold the bitmap data, i.e. it must
2431 have a size >= (WIDTH + 7) / 8 * HEIGHT
2432
2433 2. a bool-vector of size >= WIDTH * HEIGHT
2434
2435 3. a vector of strings or bool-vectors, one for each line of the
2436 bitmap.
2437
2438 4. a string that's an in-memory XBM file. Neither width nor
2439 height may be specified in this case because these are defined
2440 in the file.
2441
2442 **** XPM, image type `xpm'
2443
2444 XPM images require the external library `libXpm', package
2445 `xpm-3.4k.tar.gz', version 3.4k or later. Make sure the library is
2446 found when Emacs is configured by supplying appropriate paths via
2447 `--x-includes' and `--x-libraries'.
2448
2449 Additional image properties supported are:
2450
2451 `:color-symbols SYMBOLS'
2452
2453 SYMBOLS must be a list of pairs (NAME . COLOR), with NAME being the
2454 name of color as it appears in an XPM file, and COLOR being an X color
2455 name.
2456
2457 XPM images can be built from memory instead of files. In that case,
2458 add a `:data' property instead of a `:file' property.
2459
2460 The XPM library uses libz in its implementation so that it is able
2461 to display compressed images.
2462
2463 **** PBM, image type `pbm'
2464
2465 PBM images don't require an external library. Color, gray-scale and
2466 mono images are supported. There are no additional image properties
2467 defined.
2468
2469 **** JPEG, image type `jpeg'
2470
2471 Support for JPEG images requires the external library `libjpeg',
2472 package `jpegsrc.v6a.tar.gz', or later. Additional image properties
2473 are:
2474
2475 **** TIFF, image type `tiff'
2476
2477 Support for TIFF images requires the external library `libtiff',
2478 package `tiff-v3.4-tar.gz', or later. There are no additional image
2479 properties defined.
2480
2481 **** GIF, image type `gif'
2482
2483 Support for GIF images requires the external library `libungif', package
2484 `libungif-4.1.0', or later.
2485
2486 Additional image properties supported are:
2487
2488 `:index INDEX'
2489
2490 INDEX must be an integer >= 0. Load image number INDEX from a
2491 multi-image GIF file. An error is signalled if INDEX is too large.
2492
2493 This could be used to implement limited support for animated GIFs.
2494 For example, the following function displays a multi-image GIF file
2495 at point-min in the current buffer, switching between sub-images
2496 every 0.1 seconds.
2497
2498 (defun show-anim (file max)
2499 "Display multi-image GIF file FILE which contains MAX subimages."
2500 (display-anim (current-buffer) file 0 max t))
2501
2502 (defun display-anim (buffer file idx max first-time)
2503 (when (= idx max)
2504 (setq idx 0))
2505 (let ((img (create-image file nil nil :index idx)))
2506 (save-excursion
2507 (set-buffer buffer)
2508 (goto-char (point-min))
2509 (unless first-time (delete-char 1))
2510 (insert-image img "x"))
2511 (run-with-timer 0.1 nil 'display-anim buffer file (1+ idx) max nil)))
2512
2513 **** PNG, image type `png'
2514
2515 Support for PNG images requires the external library `libpng',
2516 package `libpng-1.0.2.tar.gz', or later. There are no additional image
2517 properties defined.
2518
2519 **** Ghostscript, image type `postscript'.
2520
2521 Additional image properties supported are:
2522
2523 `:pt-width WIDTH'
2524
2525 WIDTH is width of the image in pt (1/72 inch). WIDTH must be an
2526 integer. This is a required property.
2527
2528 `:pt-height HEIGHT'
2529
2530 HEIGHT specifies the height of the image in pt (1/72 inch). HEIGHT
2531 must be a integer. This is an required property.
2532
2533 `:bounding-box BOX'
2534
2535 BOX must be a list or vector of 4 integers giving the bounding box of
2536 the PS image, analogous to the `BoundingBox' comment found in PS
2537 files. This is an required property.
2538
2539 Part of the Ghostscript interface is implemented in Lisp. See
2540 lisp/gs.el.
2541
2542 *** Lisp interface.
2543
2544 The variable `image-types' contains a list of those image types
2545 which are supported in the current configuration.
2546
2547 Images are stored in an image cache and removed from the cache when
2548 they haven't been displayed for `image-cache-eviction-delay seconds.
2549 The function `clear-image-cache' can be used to clear the image cache
2550 manually. Images in the cache are compared with `equal', i.e. all
2551 images with `equal' specifications share the same image.
2552
2553 *** Simplified image API, image.el
2554
2555 The new Lisp package image.el contains functions that simplify image
2556 creation and putting images into text. The function `create-image'
2557 can be used to create images. The macro `defimage' can be used to
2558 define an image based on available image types. The functions
2559 `put-image' and `insert-image' can be used to insert an image into a
2560 buffer.
2561
2562 +++
2563 ** Display margins.
2564
2565 Windows can now have margins which are used for special text
2566 and images.
2567
2568 To give a window margins, either set the buffer-local variables
2569 `left-margin-width' and `right-margin-width', or call
2570 `set-window-margins'. The function `window-margins' can be used to
2571 obtain the current settings. To make `left-margin-width' and
2572 `right-margin-width' take effect, you must set them before displaying
2573 the buffer in a window, or use `set-window-buffer' to force an update
2574 of the display margins.
2575
2576 You can put text in margins by giving it a `display' text property
2577 containing a pair of the form `(LOCATION . VALUE)', where LOCATION is
2578 one of `left-margin' or `right-margin' or nil. VALUE can be either a
2579 string, an image specification or a stretch specification (see later
2580 in this file).
2581
2582 +++
2583 ** Help display
2584
2585 Emacs displays short help messages in the echo area, when the mouse
2586 moves over a tool-bar item or a piece of text that has a text property
2587 `help-echo'. This feature also applies to strings in the mode line
2588 that have a `help-echo' property.
2589
2590 The value of the `help-echo' property must be a string. For tool-bar
2591 items, their key definition is used to determine the help to display.
2592 If their definition contains a property `:help FORM', FORM is
2593 evaluated to determine the help string. Otherwise, the caption of the
2594 tool-bar item is used.
2595
2596 The hook `show-help-function' can be set to a function that displays
2597 help differently. For example, enabling a tooltip window causes the
2598 help display to appear there instead of in the echo area.
2599
2600 +++
2601 ** Vertical fractional scrolling.
2602
2603 The display of text in windows can be scrolled smoothly in pixels.
2604 This is useful, for example, for making parts of large images visible.
2605
2606 The function `window-vscroll' returns the current value of vertical
2607 scrolling, a non-negative fraction of the canonical character height.
2608 The function `set-window-vscroll' can be used to set the vertical
2609 scrolling value. Here is an example of how these function might be
2610 used.
2611
2612 (global-set-key [A-down]
2613 #'(lambda ()
2614 (interactive)
2615 (set-window-vscroll (selected-window)
2616 (+ 0.5 (window-vscroll)))))
2617 (global-set-key [A-up]
2618 #'(lambda ()
2619 (interactive)
2620 (set-window-vscroll (selected-window)
2621 (- (window-vscroll) 0.5)))))
2622
2623 +++
2624 ** New hook `fontification-functions'.
2625
2626 Functions from `fontification-functions' are called from redisplay
2627 when it encounters a region of text that is not yet fontified. This
2628 variable automatically becomes buffer-local when set. Each function
2629 is called with one argument, POS.
2630
2631 At least one of the hook functions should fontify one or more
2632 characters starting at POS in the current buffer. It should mark them
2633 as fontified by giving them a non-nil value of the `fontified' text
2634 property. It may be reasonable for these functions to check for the
2635 `fontified' property and not put it back on, but they do not have to.
2636
2637 +++
2638 ** Tool bar support.
2639
2640 Emacs supports a tool bar at the top of a frame under X. The frame
2641 parameter `tool-bar-lines' (X resource "toolBar", class "ToolBar")
2642 controls how may lines to reserve for the tool bar. A zero value
2643 suppresses the tool bar. If the value is non-zero and
2644 `auto-resize-tool-bars' is non-nil the tool bar's size will be changed
2645 automatically so that all tool bar items are visible.
2646
2647 *** Tool bar item definitions
2648
2649 Tool bar items are defined using `define-key' with a prefix-key
2650 `tool-bar'. For example `(define-key global-map [tool-bar item1] ITEM)'
2651 where ITEM is a list `(menu-item CAPTION BINDING PROPS...)'.
2652
2653 CAPTION is the caption of the item, If it's not a string, it is
2654 evaluated to get a string. The caption is currently not displayed in
2655 the tool bar, but it is displayed if the item doesn't have a `:help'
2656 property (see below).
2657
2658 BINDING is the tool bar item's binding. Tool bar items with keymaps as
2659 binding are currently ignored.
2660
2661 The following properties are recognized:
2662
2663 `:enable FORM'.
2664
2665 FORM is evaluated and specifies whether the tool bar item is enabled
2666 or disabled.
2667
2668 `:visible FORM'
2669
2670 FORM is evaluated and specifies whether the tool bar item is displayed.
2671
2672 `:filter FUNCTION'
2673
2674 FUNCTION is called with one parameter, the same list BINDING in which
2675 FUNCTION is specified as the filter. The value FUNCTION returns is
2676 used instead of BINDING to display this item.
2677
2678 `:button (TYPE SELECTED)'
2679
2680 TYPE must be one of `:radio' or `:toggle'. SELECTED is evaluated
2681 and specifies whether the button is selected (pressed) or not.
2682
2683 `:image IMAGES'
2684
2685 IMAGES is either a single image specification or a vector of four
2686 image specifications. If it is a vector, this table lists the
2687 meaning of each of the four elements:
2688
2689 Index Use when item is
2690 ----------------------------------------
2691 0 enabled and selected
2692 1 enabled and deselected
2693 2 disabled and selected
2694 3 disabled and deselected
2695
2696 If IMAGE is a single image specification, a Laplace edge-detection
2697 algorithm is used on that image to draw the image in disabled state.
2698
2699 `:help HELP-STRING'.
2700
2701 Gives a help string to display for the tool bar item. This help
2702 is displayed when the mouse is moved over the item.
2703
2704 *** Tool-bar-related variables.
2705
2706 If `auto-resize-tool-bar' is non-nil, the tool bar will automatically
2707 resize to show all defined tool bar items. It will never grow larger
2708 than 1/4 of the frame's size.
2709
2710 If `auto-raise-tool-bar-buttons' is non-nil, tool bar buttons will be
2711 raised when the mouse moves over them.
2712
2713 You can add extra space between tool bar items by setting
2714 `tool-bar-button-margin' to a positive integer specifying a number of
2715 pixels. Default is 1.
2716
2717 You can change the shadow thickness of tool bar buttons by setting
2718 `tool-bar-button-relief' to an integer. Default is 3.
2719
2720 *** Tool-bar clicks with modifiers.
2721
2722 You can bind commands to clicks with control, shift, meta etc. on
2723 a tool bar item. If
2724
2725 (define-key global-map [tool-bar shell]
2726 '(menu-item "Shell" shell
2727 :image (image :type xpm :file "shell.xpm")))
2728
2729 is the original tool bar item definition, then
2730
2731 (define-key global-map [tool-bar S-shell] 'some-command)
2732
2733 makes a binding to run `some-command' for a shifted click on the same
2734 item.
2735
2736 ** Mode line changes.
2737
2738 +++
2739 *** Mouse-sensitive mode line.
2740
2741 The mode line can be made mouse-sensitive by displaying strings there
2742 that have a `local-map' text property. There are three ways to display
2743 a string with a `local-map' property in the mode line.
2744
2745 1. The mode line spec contains a variable whose string value has
2746 a `local-map' text property.
2747
2748 2. The mode line spec contains a format specifier (e.g. `%12b'), and
2749 that format specifier has a `local-map' property.
2750
2751 3. The mode line spec contains a list containing `:eval FORM'. FORM
2752 is evaluated. If the result is a string, and that string has a
2753 `local-map' property.
2754
2755 The same mechanism is used to determine the `face' and `help-echo'
2756 properties of strings in the mode line. See `bindings.el' for an
2757 example.
2758
2759 *** If a mode line element has the form `(:eval FORM)', FORM is
2760 evaluated and the result is used as mode line element.
2761
2762 +++
2763 *** You can suppress mode-line display by setting the buffer-local
2764 variable mode-line-format to nil.
2765
2766 +++
2767 *** A headerline can now be displayed at the top of a window.
2768
2769 This mode line's contents are controlled by the new variable
2770 `header-line-format' and `default-header-line-format' which are
2771 completely analogous to `mode-line-format' and
2772 `default-mode-line-format'. A value of nil means don't display a top
2773 line.
2774
2775 The appearance of top mode lines is controlled by the face
2776 `header-line'.
2777
2778 The function `coordinates-in-window-p' returns `header-line' for a
2779 position in the header-line.
2780
2781 +++
2782 ** Text property `display'
2783
2784 The `display' text property is used to insert images into text, and
2785 also control other aspects of how text displays. The value of the
2786 `display' property should be a display specification, as described
2787 below, or a list or vector containing display specifications.
2788
2789 *** Variable width and height spaces
2790
2791 To display a space of fractional width or height, use a display
2792 specification of the form `(LOCATION STRECH)'. If LOCATION is
2793 `(margin left-margin)', the space is displayed in the left marginal
2794 area, if it is `(margin right-margin)', it is displayed in the right
2795 marginal area, and if LOCATION is `(margin nil)' the space is
2796 displayed in the text. In the latter case you can also use the
2797 simpler form STRETCH as property value.
2798
2799 The stretch specification STRETCH itself is a list of the form `(space
2800 PROPS)', where PROPS is a property list which can contain the
2801 properties described below.
2802
2803 The display of the fractional space replaces the display of the
2804 characters having the `display' property.
2805
2806 - :width WIDTH
2807
2808 Specifies that the space width should be WIDTH times the normal
2809 character width. WIDTH can be an integer or floating point number.
2810
2811 - :relative-width FACTOR
2812
2813 Specifies that the width of the stretch should be computed from the
2814 first character in a group of consecutive characters that have the
2815 same `display' property. The computation is done by multiplying the
2816 width of that character by FACTOR.
2817
2818 - :align-to HPOS
2819
2820 Specifies that the space should be wide enough to reach HPOS. The
2821 value HPOS is measured in units of the normal character width.
2822
2823 Exactly one of the above properties should be used.
2824
2825 - :height HEIGHT
2826
2827 Specifies the height of the space, as HEIGHT, measured in terms of the
2828 normal line height.
2829
2830 - :relative-height FACTOR
2831
2832 The height of the space is computed as the product of the height
2833 of the text having the `display' property and FACTOR.
2834
2835 - :ascent ASCENT
2836
2837 Specifies that ASCENT percent of the height of the stretch should be
2838 used for the ascent of the stretch, i.e. for the part above the
2839 baseline. The value of ASCENT must be a non-negative number less or
2840 equal to 100.
2841
2842 You should not use both `:height' and `:relative-height' together.
2843
2844 *** Images
2845
2846 A display specification for an image has the form `(LOCATION
2847 . IMAGE)', where IMAGE is an image specification. The image replaces,
2848 in the display, the characters having this display specification in
2849 their `display' text property. If LOCATION is `(margin left-margin)',
2850 the image will be displayed in the left marginal area, if it is
2851 `(margin right-margin)' it will be displayed in the right marginal
2852 area, and if LOCATION is `(margin nil)' the image will be displayed in
2853 the text. In the latter case you can also use the simpler form IMAGE
2854 as display specification.
2855
2856 *** Other display properties
2857
2858 - :space-width FACTOR
2859
2860 Specifies that space characters in the text having that property
2861 should be displayed FACTOR times as wide as normal; FACTOR must be an
2862 integer or float.
2863
2864 - :height HEIGHT
2865
2866 Display text having this property in a font that is smaller or larger.
2867
2868 If HEIGHT is a list of the form `(+ N)', where N is an integer, that
2869 means to use a font that is N steps larger. If HEIGHT is a list of
2870 the form `(- N)', that means to use a font that is N steps smaller. A
2871 ``step'' is defined by the set of available fonts; each size for which
2872 a font is available counts as a step.
2873
2874 If HEIGHT is a number, that means to use a font that is HEIGHT times
2875 as tall as the frame's default font.
2876
2877 If HEIGHT is a symbol, it is called as a function with the current
2878 height as argument. The function should return the new height to use.
2879
2880 Otherwise, HEIGHT is evaluated to get the new height, with the symbol
2881 `height' bound to the current specified font height.
2882
2883 - :raise FACTOR
2884
2885 FACTOR must be a number, specifying a multiple of the current
2886 font's height. If it is positive, that means to display the characters
2887 raised. If it is negative, that means to display them lower down. The
2888 amount of raising or lowering is computed without taking account of the
2889 `:height' subproperty.
2890
2891 *** Conditional display properties
2892
2893 All display specifications can be conditionalized. If a specification
2894 has the form `(:when CONDITION . SPEC)', the specification SPEC
2895 applies only when CONDITION yields a non-nil value when evaluated.
2896 During evaluattion, point is temporarily set to the end position of
2897 the text having the `display' property.
2898
2899 The normal specification consisting of SPEC only is equivalent to
2900 `(:when t SPEC)'.
2901
2902 +++
2903 ** New menu separator types.
2904
2905 Emacs now supports more than one menu separator type. Menu items with
2906 item names consisting of dashes only (including zero dashes) are
2907 treated like before. In addition, the following item names are used
2908 to specify other menu separator types.
2909
2910 - `--no-line' or `--space', or `--:space', or `--:noLine'
2911
2912 No separator lines are drawn, but a small space is inserted where the
2913 separator occurs.
2914
2915 - `--single-line' or `--:singleLine'
2916
2917 A single line in the menu's foreground color.
2918
2919 - `--double-line' or `--:doubleLine'
2920
2921 A double line in the menu's foreground color.
2922
2923 - `--single-dashed-line' or `--:singleDashedLine'
2924
2925 A single dashed line in the menu's foreground color.
2926
2927 - `--double-dashed-line' or `--:doubleDashedLine'
2928
2929 A double dashed line in the menu's foreground color.
2930
2931 - `--shadow-etched-in' or `--:shadowEtchedIn'
2932
2933 A single line with 3D sunken appearance. This is the the form
2934 displayed for item names consisting of dashes only.
2935
2936 - `--shadow-etched-out' or `--:shadowEtchedOut'
2937
2938 A single line with 3D raised appearance.
2939
2940 - `--shadow-etched-in-dash' or `--:shadowEtchedInDash'
2941
2942 A single dashed line with 3D sunken appearance.
2943
2944 - `--shadow-etched-out-dash' or `--:shadowEtchedOutDash'
2945
2946 A single dashed line with 3D raise appearance.
2947
2948 - `--shadow-double-etched-in' or `--:shadowDoubleEtchedIn'
2949
2950 Two lines with 3D sunken appearance.
2951
2952 - `--shadow-double-etched-out' or `--:shadowDoubleEtchedOut'
2953
2954 Two lines with 3D raised appearance.
2955
2956 - `--shadow-double-etched-in-dash' or `--:shadowDoubleEtchedInDash'
2957
2958 Two dashed lines with 3D sunken appearance.
2959
2960 - `--shadow-double-etched-out-dash' or `--:shadowDoubleEtchedOutDash'
2961
2962 Two dashed lines with 3D raised appearance.
2963
2964 Under LessTif/Motif, the last four separator types are displayed like
2965 the corresponding single-line separators.
2966
2967 +++
2968 ** New frame parameters for scroll bar colors.
2969
2970 The new frame parameters `scroll-bar-foreground' and
2971 `scroll-bar-background' can be used to change scroll bar colors.
2972 Their value must be either a color name, a string, or nil to specify
2973 that scroll bars should use a default color. For toolkit scroll bars,
2974 default colors are toolkit specific. For non-toolkit scroll bars, the
2975 default background is the background color of the frame, and the
2976 default foreground is black.
2977
2978 The X resource name of these parameters are `scrollBarForeground'
2979 (class ScrollBarForeground) and `scrollBarBackground' (class
2980 `ScrollBarBackground').
2981
2982 Setting these parameters overrides toolkit specific X resource
2983 settings for scroll bar colors.
2984
2985 +++
2986 ** You can set `redisplay-dont-pause' to a non-nil value to prevent
2987 display updates from being interrupted when input is pending.
2988
2989 ---
2990 ** Changing a window's width may now change its window start if it
2991 starts on a continuation line. The new window start is computed based
2992 on the window's new width, starting from the start of the continued
2993 line as the start of the screen line with the minimum distance from
2994 the original window start.
2995
2996 ---
2997 ** The variable `hscroll-step' and the functions
2998 `hscroll-point-visible' and `hscroll-window-column' have been removed
2999 now that proper horizontal scrolling is implemented.
3000
3001 +++
3002 ** Windows can now be made fixed-width and/or fixed-height.
3003
3004 A window is fixed-size if its buffer has a buffer-local variable
3005 `window-size-fixed' whose value is not nil. A value of `height' makes
3006 windows fixed-height, a value of `width' makes them fixed-width, any
3007 other non-nil value makes them both fixed-width and fixed-height.
3008
3009 The following code makes all windows displaying the current buffer
3010 fixed-width and fixed-height.
3011
3012 (set (make-local-variable 'window-size-fixed) t)
3013
3014 A call to enlarge-window on a window gives an error if that window is
3015 fixed-width and it is tried to change the window's width, or if the
3016 window is fixed-height, and it is tried to change its height. To
3017 change the size of a fixed-size window, bind `window-size-fixed'
3018 temporarily to nil, for example
3019
3020 (let ((window-size-fixed nil))
3021 (enlarge-window 10))
3022
3023 Likewise, an attempt to split a fixed-height window vertically,
3024 or a fixed-width window horizontally results in a error.
3025
3026 ** The cursor-type frame parameter is now supported on MS-DOS
3027 terminals. When Emacs starts, it by default changes the cursor shape
3028 to a solid box, as it does on Unix. The `cursor-type' frame parameter
3029 overrides this as it does on Unix, except that the bar cursor is
3030 horizontal rather than vertical (since the MS-DOS display doesn't
3031 support a vertical-bar cursor).
3032 ^L
3033 * Emacs 20.5 is a bug-fix release with no user-visible changes.
3034
3035 ** Not new, but not mentioned before:
3036 M-w when Transient Mark mode is enabled disables the mark.
3037 \f
3038 * Changes in Emacs 20.4
3039
3040 ** Init file may be called .emacs.el.
3041
3042 You can now call the Emacs init file `.emacs.el'.
3043 Formerly the name had to be `.emacs'. If you use the name
3044 `.emacs.el', you can byte-compile the file in the usual way.
3045
3046 If both `.emacs' and `.emacs.el' exist, the latter file
3047 is the one that is used.
3048
3049 ** shell-command, and shell-command-on-region, now return
3050 the exit code of the command (unless it is asynchronous).
3051 Also, you can specify a place to put the error output,
3052 separate from the command's regular output.
3053 Interactively, the variable shell-command-default-error-buffer
3054 says where to put error output; set it to a buffer name.
3055 In calls from Lisp, an optional argument ERROR-BUFFER specifies
3056 the buffer name.
3057
3058 When you specify a non-nil error buffer (or buffer name), any error
3059 output is inserted before point in that buffer, with \f\n to separate
3060 it from the previous batch of error output. The error buffer is not
3061 cleared, so error output from successive commands accumulates there.
3062
3063 ** Setting the default value of enable-multibyte-characters to nil in
3064 the .emacs file, either explicitly using setq-default, or via Custom,
3065 is now essentially equivalent to using --unibyte: all buffers
3066 created during startup will be made unibyte after loading .emacs.
3067
3068 ** C-x C-f now handles the wildcards * and ? in file names. For
3069 example, typing C-x C-f c*.c RET visits all the files whose names
3070 match c*.c. To visit a file whose name contains * or ?, add the
3071 quoting sequence /: to the beginning of the file name.
3072
3073 ** The M-x commands keep-lines, flush-lines and count-matches
3074 now have the same feature as occur and query-replace:
3075 if the pattern contains any upper case letters, then
3076 they never ignore case.
3077
3078 ** The end-of-line format conversion feature previously mentioned
3079 under `* Emacs 20.1 changes for MS-DOS and MS-Windows' actually
3080 applies to all operating systems. Emacs recognizes from the contents
3081 of a file what convention it uses to separate lines--newline, CRLF, or
3082 just CR--and automatically converts the contents to the normal Emacs
3083 convention (using newline to separate lines) for editing. This is a
3084 part of the general feature of coding system conversion.
3085
3086 If you subsequently save the buffer, Emacs converts the text back to
3087 the same format that was used in the file before.
3088
3089 You can turn off end-of-line conversion by setting the variable
3090 `inhibit-eol-conversion' to non-nil, e.g. with Custom in the MULE group.
3091
3092 ** The character set property `prefered-coding-system' has been
3093 renamed to `preferred-coding-system', for the sake of correct spelling.
3094 This is a fairly internal feature, so few programs should be affected.
3095
3096 ** Mode-line display of end-of-line format is changed.
3097 The indication of the end-of-line format of the file visited by a
3098 buffer is now more explicit when that format is not the usual one for
3099 your operating system. For example, the DOS-style end-of-line format
3100 is displayed as "(DOS)" on Unix and GNU/Linux systems. The usual
3101 end-of-line format is still displayed as a single character (colon for
3102 Unix, backslash for DOS and Windows, and forward slash for the Mac).
3103
3104 The values of the variables eol-mnemonic-unix, eol-mnemonic-dos,
3105 eol-mnemonic-mac, and eol-mnemonic-undecided, which are strings,
3106 control what is displayed in the mode line for each end-of-line
3107 format. You can now customize these variables.
3108
3109 ** In the previous version of Emacs, tar-mode didn't work well if a
3110 filename contained non-ASCII characters. Now this is fixed. Such a
3111 filename is decoded by file-name-coding-system if the default value of
3112 enable-multibyte-characters is non-nil.
3113
3114 ** The command temp-buffer-resize-mode toggles a minor mode
3115 in which temporary buffers (such as help buffers) are given
3116 windows just big enough to hold the whole contents.
3117
3118 ** If you use completion.el, you must now run the function
3119 dynamic-completion-mode to enable it. Just loading the file
3120 doesn't have any effect.
3121
3122 ** In Flyspell mode, the default is now to make just one Ispell process,
3123 not one per buffer.
3124
3125 ** If you use iswitchb but do not call (iswitchb-default-keybindings) to
3126 use the default keybindings, you will need to add the following line:
3127 (add-hook 'minibuffer-setup-hook 'iswitchb-minibuffer-setup)
3128
3129 ** Auto-show mode is no longer enabled just by loading auto-show.el.
3130 To control it, set `auto-show-mode' via Custom or use the
3131 `auto-show-mode' command.
3132
3133 ** Handling of X fonts' ascent/descent parameters has been changed to
3134 avoid redisplay problems. As a consequence, compared with previous
3135 versions the line spacing and frame size now differ with some font
3136 choices, typically increasing by a pixel per line. This change
3137 occurred in version 20.3 but was not documented then.
3138
3139 ** If you select the bar cursor style, it uses the frame's
3140 cursor-color, rather than the cursor foreground pixel.
3141
3142 ** In multibyte mode, Rmail decodes incoming MIME messages using the
3143 character set specified in the message. If you want to disable this
3144 feature, set the variable rmail-decode-mime-charset to nil.
3145
3146 ** Not new, but not mentioned previously in NEWS: when you use #! at
3147 the beginning of a file to make it executable and specify an
3148 interpreter program, Emacs looks on the second line for the -*- mode
3149 and variable specification, as well as on the first line.
3150
3151 ** Support for IBM codepage encoding of non-ASCII characters.
3152
3153 The new command M-x codepage-setup creates a special coding system
3154 that can be used to convert text between a specific IBM codepage and
3155 one of the character sets built into Emacs which matches that
3156 codepage. For example, codepage 850 corresponds to Latin-1 character
3157 set, codepage 855 corresponds to Cyrillic-ISO character set, etc.
3158
3159 Windows codepages 1250, 1251 and some others, where Windows deviates
3160 from the corresponding ISO character set, are also supported.
3161
3162 IBM box-drawing characters and other glyphs which don't have
3163 equivalents in the corresponding ISO character set, are converted to
3164 a character defined by dos-unsupported-char-glyph on MS-DOS, and to
3165 `?' on other systems.
3166
3167 IBM codepages are widely used on MS-DOS and MS-Windows, so this
3168 feature is most useful on those platforms, but it can also be used on
3169 Unix.
3170
3171 Emacs compiled for MS-DOS automatically loads the support for the
3172 current codepage when it starts.
3173
3174 ** Mail changes
3175
3176 *** When mail is sent using compose-mail (C-x m), and if
3177 `mail-send-nonascii' is set to the new default value `mime',
3178 appropriate MIME headers are added. The headers are added only if
3179 non-ASCII characters are present in the body of the mail, and no other
3180 MIME headers are already present. For example, the following three
3181 headers are added if the coding system used in the *mail* buffer is
3182 latin-1:
3183
3184 MIME-version: 1.0
3185 Content-type: text/plain; charset=iso-8859-1
3186 Content-Transfer-Encoding: 8bit
3187
3188 *** The new variable default-sendmail-coding-system specifies the
3189 default way to encode outgoing mail. This has higher priority than
3190 default-buffer-file-coding-system but has lower priority than
3191 sendmail-coding-system and the local value of
3192 buffer-file-coding-system.
3193
3194 You should not set this variable manually. Instead, set
3195 sendmail-coding-system to specify a fixed encoding for all outgoing
3196 mail.
3197
3198 *** When you try to send a message that contains non-ASCII characters,
3199 if the coding system specified by those variables doesn't handle them,
3200 Emacs will ask you to select a suitable coding system while showing a
3201 list of possible coding systems.
3202
3203 ** CC Mode changes
3204
3205 *** c-default-style can now take an association list that maps major
3206 modes to style names. When this variable is an alist, Java mode no
3207 longer hardcodes a setting to "java" style. See the variable's
3208 docstring for details.
3209
3210 *** It's now possible to put a list as the offset on a syntactic
3211 symbol. The list is evaluated recursively until a non-nil offset is
3212 found. This is useful to combine several lineup functions to act in a
3213 prioritized order on a single line. However, none of the supplied
3214 lineup functions use this feature currently.
3215
3216 *** New syntactic symbol catch-clause, which is used on the "catch" and
3217 "finally" lines in try-catch constructs in C++ and Java.
3218
3219 *** New cleanup brace-catch-brace on c-cleanup-list, which does for
3220 "catch" lines what brace-elseif-brace does for "else if" lines.
3221
3222 *** The braces of Java anonymous inner classes are treated separately
3223 from the braces of other classes in auto-newline mode. Two new
3224 symbols inexpr-class-open and inexpr-class-close may be used on
3225 c-hanging-braces-alist to control the automatic newlines used for
3226 anonymous classes.
3227
3228 *** Support for the Pike language added, along with new Pike specific
3229 syntactic symbols: inlambda, lambda-intro-cont
3230
3231 *** Support for Java anonymous classes via new syntactic symbol
3232 inexpr-class. New syntactic symbol inexpr-statement for Pike
3233 support and gcc-style statements inside expressions. New lineup
3234 function c-lineup-inexpr-block.
3235
3236 *** New syntactic symbol brace-entry-open which is used in brace lists
3237 (i.e. static initializers) when a list entry starts with an open
3238 brace. These used to be recognized as brace-list-entry's.
3239 c-electric-brace also recognizes brace-entry-open braces
3240 (brace-list-entry's can no longer be electrified).
3241
3242 *** New command c-indent-line-or-region, not bound by default.
3243
3244 *** `#' is only electric when typed in the indentation of a line.
3245
3246 *** Parentheses are now electric (via the new command c-electric-paren)
3247 for auto-reindenting lines when parens are typed.
3248
3249 *** In "gnu" style, inline-open offset is now set to zero.
3250
3251 *** Uniform handling of the inclass syntactic symbol. The indentation
3252 associated with it is now always relative to the class opening brace.
3253 This means that the indentation behavior has changed in some
3254 circumstances, but only if you've put anything besides 0 on the
3255 class-open syntactic symbol (none of the default styles do that).
3256
3257 ** Gnus changes.
3258
3259 *** New functionality for using Gnus as an offline newsreader has been
3260 added. A plethora of new commands and modes have been added. See the
3261 Gnus manual for the full story.
3262
3263 *** The nndraft backend has returned, but works differently than
3264 before. All Message buffers are now also articles in the nndraft
3265 group, which is created automatically.
3266
3267 *** `gnus-alter-header-function' can now be used to alter header
3268 values.
3269
3270 *** `gnus-summary-goto-article' now accept Message-ID's.
3271
3272 *** A new Message command for deleting text in the body of a message
3273 outside the region: `C-c C-v'.
3274
3275 *** You can now post to component group in nnvirtual groups with
3276 `C-u C-c C-c'.
3277
3278 *** `nntp-rlogin-program' -- new variable to ease customization.
3279
3280 *** `C-u C-c C-c' in `gnus-article-edit-mode' will now inhibit
3281 re-highlighting of the article buffer.
3282
3283 *** New element in `gnus-boring-article-headers' -- `long-to'.
3284
3285 *** `M-i' symbolic prefix command. See the section "Symbolic
3286 Prefixes" in the Gnus manual for details.
3287
3288 *** `L' and `I' in the summary buffer now take the symbolic prefix
3289 `a' to add the score rule to the "all.SCORE" file.
3290
3291 *** `gnus-simplify-subject-functions' variable to allow greater
3292 control over simplification.
3293
3294 *** `A T' -- new command for fetching the current thread.
3295
3296 *** `/ T' -- new command for including the current thread in the
3297 limit.
3298
3299 *** `M-RET' is a new Message command for breaking cited text.
3300
3301 *** \\1-expressions are now valid in `nnmail-split-methods'.
3302
3303 *** The `custom-face-lookup' function has been removed.
3304 If you used this function in your initialization files, you must
3305 rewrite them to use `face-spec-set' instead.
3306
3307 *** Cancelling now uses the current select method. Symbolic prefix
3308 `a' forces normal posting method.
3309
3310 *** New command to translate M******** sm*rtq**t*s into proper text
3311 -- `W d'.
3312
3313 *** For easier debugging of nntp, you can set `nntp-record-commands'
3314 to a non-nil value.
3315
3316 *** nntp now uses ~/.authinfo, a .netrc-like file, for controlling
3317 where and how to send AUTHINFO to NNTP servers.
3318
3319 *** A command for editing group parameters from the summary buffer
3320 has been added.
3321
3322 *** A history of where mails have been split is available.
3323
3324 *** A new article date command has been added -- `article-date-iso8601'.
3325
3326 *** Subjects can be simplified when threading by setting
3327 `gnus-score-thread-simplify'.
3328
3329 *** A new function for citing in Message has been added --
3330 `message-cite-original-without-signature'.
3331
3332 *** `article-strip-all-blank-lines' -- new article command.
3333
3334 *** A new Message command to kill to the end of the article has
3335 been added.
3336
3337 *** A minimum adaptive score can be specified by using the
3338 `gnus-adaptive-word-minimum' variable.
3339
3340 *** The "lapsed date" article header can be kept continually
3341 updated by the `gnus-start-date-timer' command.
3342
3343 *** Web listserv archives can be read with the nnlistserv backend.
3344
3345 *** Old dejanews archives can now be read by nnweb.
3346
3347 *** `gnus-posting-styles' has been re-activated.
3348
3349 ** Changes to TeX and LaTeX mode
3350
3351 *** The new variable `tex-start-options-string' can be used to give
3352 options for the TeX run. The default value causes TeX to run in
3353 nonstopmode. For an interactive TeX run set it to nil or "".
3354
3355 *** The command `tex-feed-input' sends input to the Tex Shell. In a
3356 TeX buffer it is bound to the keys C-RET, C-c RET, and C-c C-m (some
3357 of these keys may not work on all systems). For instance, if you run
3358 TeX interactively and if the TeX run stops because of an error, you
3359 can continue it without leaving the TeX buffer by typing C-RET.
3360
3361 *** The Tex Shell Buffer is now in `compilation-shell-minor-mode'.
3362 All error-parsing commands of the Compilation major mode are available
3363 but bound to keys that don't collide with the shell. Thus you can use
3364 the Tex Shell for command line executions like a usual shell.
3365
3366 *** The commands `tex-validate-region' and `tex-validate-buffer' check
3367 the matching of braces and $'s. The errors are listed in a *Occur*
3368 buffer and you can use C-c C-c or mouse-2 to go to a particular
3369 mismatch.
3370
3371 ** Changes to RefTeX mode
3372
3373 *** The table of contents buffer can now also display labels and
3374 file boundaries in addition to sections. Use `l', `i', and `c' keys.
3375
3376 *** Labels derived from context (the section heading) are now
3377 lowercase by default. To make the label legal in LaTeX, latin-1
3378 characters will lose their accent. All Mule characters will be
3379 removed from the label.
3380
3381 *** The automatic display of cross reference information can also use
3382 a window instead of the echo area. See variable `reftex-auto-view-crossref'.
3383
3384 *** kpsewhich can be used by RefTeX to find TeX and BibTeX files. See the
3385 customization group `reftex-finding-files'.
3386
3387 *** The option `reftex-bibfile-ignore-list' has been renamed to
3388 `reftex-bibfile-ignore-regexps' and indeed can be fed with regular
3389 expressions.
3390
3391 *** Multiple Selection buffers are now hidden buffers.
3392
3393 ** New/deleted modes and packages
3394
3395 *** The package snmp-mode.el provides major modes for editing SNMP and
3396 SNMPv2 MIBs. It has entries on `auto-mode-alist'.
3397
3398 *** The package sql.el provides a major mode, M-x sql-mode, for
3399 editing SQL files, and M-x sql-interactive-mode for interacting with
3400 SQL interpreters. It has an entry on `auto-mode-alist'.
3401
3402 *** M-x highlight-changes-mode provides a minor mode displaying buffer
3403 changes with a special face.
3404
3405 *** ispell4.el has been deleted. It got in the way of ispell.el and
3406 this was hard to fix reliably. It has long been obsolete -- use
3407 Ispell 3.1 and ispell.el.
3408 \f
3409 * MS-DOS changes in Emacs 20.4
3410
3411 ** Emacs compiled for MS-DOS now supports MULE features better.
3412 This includes support for display of all ISO 8859-N character sets,
3413 conversion to and from IBM codepage encoding of non-ASCII characters,
3414 and automatic setup of the MULE environment at startup. For details,
3415 check out the section `MS-DOS and MULE' in the manual.
3416
3417 The MS-DOS installation procedure automatically configures and builds
3418 Emacs with input method support if it finds an unpacked Leim
3419 distribution when the config.bat script is run.
3420
3421 ** Formerly, the value of lpr-command did not affect printing on
3422 MS-DOS unless print-region-function was set to nil, but now it
3423 controls whether an external program is invoked or output is written
3424 directly to a printer port. Similarly, in the previous version of
3425 Emacs, the value of ps-lpr-command did not affect PostScript printing
3426 on MS-DOS unless ps-printer-name was set to something other than a
3427 string (eg. t or `pipe'), but now it controls whether an external
3428 program is used. (These changes were made so that configuration of
3429 printing variables would be almost identical across all platforms.)
3430
3431 ** In the previous version of Emacs, PostScript and non-PostScript
3432 output was piped to external programs, but because most print programs
3433 available for MS-DOS and MS-Windows cannot read data from their standard
3434 input, on those systems the data to be output is now written to a
3435 temporary file whose name is passed as the last argument to the external
3436 program.
3437
3438 An exception is made for `print', a standard program on Windows NT,
3439 and `nprint', a standard program on Novell Netware. For both of these
3440 programs, the command line is constructed in the appropriate syntax
3441 automatically, using only the value of printer-name or ps-printer-name
3442 as appropriate--the value of the relevant `-switches' variable is
3443 ignored, as both programs have no useful switches.
3444
3445 ** The value of the variable dos-printer (cf. dos-ps-printer), if it has
3446 a value, overrides the value of printer-name (cf. ps-printer-name), on
3447 MS-DOS and MS-Windows only. This has been true since version 20.3, but
3448 was not documented clearly before.
3449
3450 ** All the Emacs games now work on MS-DOS terminals.
3451 This includes Tetris and Snake.
3452 \f
3453 * Lisp changes in Emacs 20.4
3454
3455 ** New functions line-beginning-position and line-end-position
3456 return the position of the beginning or end of the current line.
3457 They both accept an optional argument, which has the same
3458 meaning as the argument to beginning-of-line or end-of-line.
3459
3460 ** find-file and allied functions now have an optional argument
3461 WILDCARD. If this is non-nil, they do wildcard processing,
3462 and visit all files that match the wildcard pattern.
3463
3464 ** Changes in the file-attributes function.
3465
3466 *** The file size returned by file-attributes may be an integer or a float.
3467 It is an integer if the size fits in a Lisp integer, float otherwise.
3468
3469 *** The inode number returned by file-attributes may be an integer (if
3470 the number fits in a Lisp integer) or a cons cell containing two
3471 integers.
3472
3473 ** The new function directory-files-and-attributes returns a list of
3474 files in a directory and their attributes. It accepts the same
3475 arguments as directory-files and has similar semantics, except that
3476 file names and attributes are returned.
3477
3478 ** The new function file-attributes-lessp is a helper function for
3479 sorting the list generated by directory-files-and-attributes. It
3480 accepts two arguments, each a list of a file name and its atttributes.
3481 It compares the file names of each according to string-lessp and
3482 returns the result.
3483
3484 ** The new function file-expand-wildcards expands a wildcard-pattern
3485 to produce a list of existing files that match the pattern.
3486
3487 ** New functions for base64 conversion:
3488
3489 The function base64-encode-region converts a part of the buffer
3490 into the base64 code used in MIME. base64-decode-region
3491 performs the opposite conversion. Line-breaking is supported
3492 optionally.
3493
3494 Functions base64-encode-string and base64-decode-string do a similar
3495 job on the text in a string. They return the value as a new string.
3496
3497 **
3498 The new function process-running-child-p
3499 will tell you if a subprocess has given control of its
3500 terminal to its own child process.
3501
3502 ** interrupt-process and such functions have a new feature:
3503 when the second argument is `lambda', they send a signal
3504 to the running child of the subshell, if any, but if the shell
3505 itself owns its terminal, no signal is sent.
3506
3507 ** There are new widget types `plist' and `alist' which can
3508 be used for customizing variables whose values are plists or alists.
3509
3510 ** easymenu.el Now understands `:key-sequence' and `:style button'.
3511 :included is an alias for :visible.
3512
3513 easy-menu-add-item now understands the values returned by
3514 easy-menu-remove-item and easy-menu-item-present-p. This can be used
3515 to move or copy menu entries.
3516
3517 ** Multibyte editing changes
3518
3519 *** The definitions of sref and char-bytes are changed. Now, sref is
3520 an alias of aref and char-bytes always returns 1. This change is to
3521 make some Emacs Lisp code which works on 20.2 and earlier also
3522 work on the latest Emacs. Such code uses a combination of sref and
3523 char-bytes in a loop typically as below:
3524 (setq char (sref str idx)
3525 idx (+ idx (char-bytes idx)))
3526 The byte-compiler now warns that this is obsolete.
3527
3528 If you want to know how many bytes a specific multibyte character
3529 (say, CH) occupies in a multibyte buffer, use this code:
3530 (charset-bytes (char-charset ch))
3531
3532 *** In multibyte mode, when you narrow a buffer to some region, and the
3533 region is preceded or followed by non-ASCII codes, inserting or
3534 deleting at the head or the end of the region may signal this error:
3535
3536 Byte combining across boundary of accessible buffer text inhibitted
3537
3538 This is to avoid some bytes being combined together into a character
3539 across the boundary.
3540
3541 *** The functions find-charset-region and find-charset-string include
3542 `unknown' in the returned list in the following cases:
3543 o The current buffer or the target string is unibyte and
3544 contains 8-bit characters.
3545 o The current buffer or the target string is multibyte and
3546 contains invalid characters.
3547
3548 *** The functions decode-coding-region and encode-coding-region remove
3549 text properties of the target region. Ideally, they should correctly
3550 preserve text properties, but for the moment, it's hard. Removing
3551 text properties is better than preserving them in a less-than-correct
3552 way.
3553
3554 *** prefer-coding-system sets EOL conversion of default coding systems.
3555 If the argument to prefer-coding-system specifies a certain type of
3556 end of line conversion, the default coding systems set by
3557 prefer-coding-system will specify that conversion type for end of line.
3558
3559 *** The new function thai-compose-string can be used to properly
3560 compose Thai characters in a string.
3561
3562 ** The primitive `define-prefix-command' now takes an optional third
3563 argument NAME, which should be a string. It supplies the menu name
3564 for the created keymap. Keymaps created in order to be displayed as
3565 menus should always use the third argument.
3566
3567 ** The meanings of optional second arguments for read-char,
3568 read-event, and read-char-exclusive are flipped. Now the second
3569 arguments are INHERIT-INPUT-METHOD. These functions use the current
3570 input method (if any) if and only if INHERIT-INPUT-METHOD is non-nil.
3571
3572 ** The new function clear-this-command-keys empties out the contents
3573 of the vector that (this-command-keys) returns. This is useful in
3574 programs that read passwords, to prevent the passwords from echoing
3575 inadvertently as part of the next command in certain cases.
3576
3577 ** The new macro `with-temp-message' displays a temporary message in
3578 the echo area, while executing some Lisp code. Like `progn', it
3579 returns the value of the last form, but it also restores the previous
3580 echo area contents.
3581
3582 (with-temp-message MESSAGE &rest BODY)
3583
3584 ** The function `require' now takes an optional third argument
3585 NOERROR. If it is non-nil, then there is no error if the
3586 requested feature cannot be loaded.
3587
3588 ** In the function modify-face, an argument of (nil) for the
3589 foreground color, background color or stipple pattern
3590 means to clear out that attribute.
3591
3592 ** The `outer-window-id' frame property of an X frame
3593 gives the window number of the outermost X window for the frame.
3594
3595 ** Temporary buffers made with with-output-to-temp-buffer are now
3596 read-only by default, and normally use the major mode Help mode
3597 unless you put them in some other non-Fundamental mode before the
3598 end of with-output-to-temp-buffer.
3599
3600 ** The new functions gap-position and gap-size return information on
3601 the gap of the current buffer.
3602
3603 ** The new functions position-bytes and byte-to-position provide a way
3604 to convert between character positions and byte positions in the
3605 current buffer.
3606
3607 ** vc.el defines two new macros, `edit-vc-file' and `with-vc-file', to
3608 facilitate working with version-controlled files from Lisp programs.
3609 These macros check out a given file automatically if needed, and check
3610 it back in after any modifications have been made.
3611 \f
3612 * Installation Changes in Emacs 20.3
3613
3614 ** The default value of load-path now includes most subdirectories of
3615 the site-specific directories /usr/local/share/emacs/site-lisp and
3616 /usr/local/share/emacs/VERSION/site-lisp, in addition to those
3617 directories themselves. Both immediate subdirectories and
3618 subdirectories multiple levels down are added to load-path.
3619
3620 Not all subdirectories are included, though. Subdirectories whose
3621 names do not start with a letter or digit are excluded.
3622 Subdirectories named RCS or CVS are excluded. Also, a subdirectory
3623 which contains a file named `.nosearch' is excluded. You can use
3624 these methods to prevent certain subdirectories from being searched.
3625
3626 Emacs finds these subdirectories and adds them to load-path when it
3627 starts up. While it would be cleaner to find the subdirectories each
3628 time Emacs loads a file, that would be much slower.
3629
3630 This feature is an incompatible change. If you have stored some Emacs
3631 Lisp files in a subdirectory of the site-lisp directory specifically
3632 to prevent them from being used, you will need to rename the
3633 subdirectory to start with a non-alphanumeric character, or create a
3634 `.nosearch' file in it, in order to continue to achieve the desired
3635 results.
3636
3637 ** Emacs no longer includes an old version of the C preprocessor from
3638 GCC. This was formerly used to help compile Emacs with C compilers
3639 that had limits on the significant length of an identifier, but in
3640 fact we stopped supporting such compilers some time ago.
3641 \f
3642 * Changes in Emacs 20.3
3643
3644 ** The new command C-x z (repeat) repeats the previous command
3645 including its argument. If you repeat the z afterward,
3646 it repeats the command additional times; thus, you can
3647 perform many repetitions with one keystroke per repetition.
3648
3649 ** Emacs now supports "selective undo" which undoes only within a
3650 specified region. To do this, set point and mark around the desired
3651 region and type C-u C-x u (or C-u C-_). You can then continue undoing
3652 further, within the same region, by repeating the ordinary undo
3653 command C-x u or C-_. This will keep undoing changes that were made
3654 within the region you originally specified, until either all of them
3655 are undone, or it encounters a change which crosses the edge of that
3656 region.
3657
3658 In Transient Mark mode, undoing when a region is active requests
3659 selective undo.
3660
3661 ** If you specify --unibyte when starting Emacs, then all buffers are
3662 unibyte, except when a Lisp program specifically creates a multibyte
3663 buffer. Setting the environment variable EMACS_UNIBYTE has the same
3664 effect. The --no-unibyte option overrides EMACS_UNIBYTE and directs
3665 Emacs to run normally in multibyte mode.
3666
3667 The option --unibyte does not affect the reading of Emacs Lisp files,
3668 though. If you want a Lisp file to be read in unibyte mode, use
3669 -*-unibyte: t;-*- on its first line. That will force Emacs to
3670 load that file in unibyte mode, regardless of how Emacs was started.
3671
3672 ** toggle-enable-multibyte-characters no longer has a key binding and
3673 no longer appears in the menu bar. We've realized that changing the
3674 enable-multibyte-characters variable in an existing buffer is
3675 something that most users not do.
3676
3677 ** You can specify a coding system to use for the next cut or paste
3678 operations through the window system with the command C-x RET X.
3679 The coding system can make a difference for communication with other
3680 applications.
3681
3682 C-x RET x specifies a coding system for all subsequent cutting and
3683 pasting operations.
3684
3685 ** You can specify the printer to use for commands that do printing by
3686 setting the variable `printer-name'. Just what a printer name looks
3687 like depends on your operating system. You can specify a different
3688 printer for the Postscript printing commands by setting
3689 `ps-printer-name'.
3690
3691 ** Emacs now supports on-the-fly spell checking by the means of a
3692 minor mode. It is called M-x flyspell-mode. You don't have to remember
3693 any other special commands to use it, and you will hardly notice it
3694 except when you make a spelling error. Flyspell works by highlighting
3695 incorrect words as soon as they are completed or as soon as the cursor
3696 hits a new word.
3697
3698 Flyspell mode works with whichever dictionary you have selected for
3699 Ispell in Emacs. In TeX mode, it understands TeX syntax so as not
3700 to be confused by TeX commands.
3701
3702 You can correct a misspelled word by editing it into something
3703 correct. You can also correct it, or accept it as correct, by
3704 clicking on the word with Mouse-2; that gives you a pop-up menu
3705 of various alternative replacements and actions.
3706
3707 Flyspell mode also proposes "automatic" corrections. M-TAB replaces
3708 the current misspelled word with a possible correction. If several
3709 corrections are made possible, M-TAB cycles through them in
3710 alphabetical order, or in order of decreasing likelihood if
3711 flyspell-sort-corrections is nil.
3712
3713 Flyspell mode also flags an error when a word is repeated, if
3714 flyspell-mark-duplications-flag is non-nil.
3715
3716 ** Changes in input method usage.
3717
3718 Now you can use arrow keys (right, left, down, up) for selecting among
3719 the alternatives just the same way as you do by C-f, C-b, C-n, and C-p
3720 respectively.
3721
3722 You can use the ENTER key to accept the current conversion.
3723
3724 If you type TAB to display a list of alternatives, you can select one
3725 of the alternatives with Mouse-2.
3726
3727 The meaning of the variable `input-method-verbose-flag' is changed so
3728 that you can set it to t, nil, `default', or `complex-only'.
3729
3730 If the value is nil, extra guidance is never given.
3731
3732 If the value is t, extra guidance is always given.
3733
3734 If the value is `complex-only', extra guidance is always given only
3735 when you are using complex input methods such as chinese-py.
3736
3737 If the value is `default' (this is the default), extra guidance is
3738 given in the following case:
3739 o When you are using a complex input method.
3740 o When you are using a simple input method but not in the minibuffer.
3741
3742 If you are using Emacs through a very slow line, setting
3743 input-method-verbose-flag to nil or to complex-only is a good choice,
3744 and if you are using an input method you are not familiar with,
3745 setting it to t is helpful.
3746
3747 The old command select-input-method is now called set-input-method.
3748
3749 In the language environment "Korean", you can use the following
3750 keys:
3751 Shift-SPC toggle-korean-input-method
3752 C-F9 quail-hangul-switch-symbol-ksc
3753 F9 quail-hangul-switch-hanja
3754 These key bindings are canceled when you switch to another language
3755 environment.
3756
3757 ** The minibuffer history of file names now records the specified file
3758 names, not the entire minibuffer input. For example, if the
3759 minibuffer starts out with /usr/foo/, you might type in /etc/passwd to
3760 get
3761
3762 /usr/foo//etc/passwd
3763
3764 which stands for the file /etc/passwd.
3765
3766 Formerly, this used to put /usr/foo//etc/passwd in the history list.
3767 Now this puts just /etc/passwd in the history list.
3768
3769 ** If you are root, Emacs sets backup-by-copying-when-mismatch to t
3770 at startup, so that saving a file will be sure to preserve
3771 its owner and group.
3772
3773 ** find-func.el can now also find the place of definition of Emacs
3774 Lisp variables in user-loaded libraries.
3775
3776 ** C-x r t (string-rectangle) now deletes the existing rectangle
3777 contents before inserting the specified string on each line.
3778
3779 ** There is a new command delete-whitespace-rectangle
3780 which deletes whitespace starting from a particular column
3781 in all the lines on a rectangle. The column is specified
3782 by the left edge of the rectangle.
3783
3784 ** You can now store a number into a register with C-u NUMBER C-x r n REG,
3785 increment it by INC with C-u INC C-x r + REG (to increment by one, omit
3786 C-u INC), and insert it in the buffer with C-x r g REG. This is useful
3787 for writing keyboard macros.
3788
3789 ** The new command M-x speedbar displays a frame in which directories,
3790 files, and tags can be displayed, manipulated, and jumped to. The
3791 frame defaults to 20 characters in width, and is the same height as
3792 the frame that it was started from. Some major modes define
3793 additional commands for the speedbar, including Rmail, GUD/GDB, and
3794 info.
3795
3796 ** query-replace-regexp is now bound to C-M-%.
3797
3798 ** In Transient Mark mode, when the region is active, M-x
3799 query-replace and the other replace commands now operate on the region
3800 contents only.
3801
3802 ** M-x write-region, when used interactively, now asks for
3803 confirmation before overwriting an existing file. When you call
3804 the function from a Lisp program, a new optional argument CONFIRM
3805 says whether to ask for confirmation in this case.
3806
3807 ** If you use find-file-literally and the file is already visited
3808 non-literally, the command asks you whether to revisit the file
3809 literally. If you say no, it signals an error.
3810
3811 ** Major modes defined with the "derived mode" feature
3812 now use the proper name for the mode hook: WHATEVER-mode-hook.
3813 Formerly they used the name WHATEVER-mode-hooks, but that is
3814 inconsistent with Emacs conventions.
3815
3816 ** shell-command-on-region (and shell-command) reports success or
3817 failure if the command produces no output.
3818
3819 ** Set focus-follows-mouse to nil if your window system or window
3820 manager does not transfer focus to another window when you just move
3821 the mouse.
3822
3823 ** mouse-menu-buffer-maxlen has been renamed to
3824 mouse-buffer-menu-maxlen to be consistent with the other related
3825 function and variable names.
3826
3827 ** The new variable auto-coding-alist specifies coding systems for
3828 reading specific files. This has higher priority than
3829 file-coding-system-alist.
3830
3831 ** If you set the variable unibyte-display-via-language-environment to
3832 t, then Emacs displays non-ASCII characters are displayed by
3833 converting them to the equivalent multibyte characters according to
3834 the current language environment. As a result, they are displayed
3835 according to the current fontset.
3836
3837 ** C-q's handling of codes in the range 0200 through 0377 is changed.
3838
3839 The codes in the range 0200 through 0237 are inserted as one byte of
3840 that code regardless of the values of nonascii-translation-table and
3841 nonascii-insert-offset.
3842
3843 For the codes in the range 0240 through 0377, if
3844 enable-multibyte-characters is non-nil and nonascii-translation-table
3845 nor nonascii-insert-offset can't convert them to valid multibyte
3846 characters, they are converted to Latin-1 characters.
3847
3848 ** If you try to find a file that is not read-accessible, you now get
3849 an error, rather than an empty buffer and a warning.
3850
3851 ** In the minibuffer history commands M-r and M-s, an upper case
3852 letter in the regular expression forces case-sensitive search.
3853
3854 ** In the *Help* buffer, cross-references to commands and variables
3855 are inferred and hyperlinked. Use C-h m in Help mode for the relevant
3856 command keys.
3857
3858 ** M-x apropos-command, with a prefix argument, no longer looks for
3859 user option variables--instead it looks for noninteractive functions.
3860
3861 Meanwhile, the command apropos-variable normally searches for
3862 user option variables; with a prefix argument, it looks at
3863 all variables that have documentation.
3864
3865 ** When you type a long line in the minibuffer, and the minibuffer
3866 shows just one line, automatically scrolling works in a special way
3867 that shows you overlap with the previous line of text. The variable
3868 minibuffer-scroll-overlap controls how many characters of overlap
3869 it should show; the default is 20.
3870
3871 Meanwhile, Resize Minibuffer mode is still available; in that mode,
3872 the minibuffer grows taller (up to a point) as needed to show the whole
3873 of your input.
3874
3875 ** The new command M-x customize-changed-options lets you customize
3876 all the options whose meanings or default values have changed in
3877 recent Emacs versions. You specify a previous Emacs version number as
3878 argument, and the command creates a customization buffer showing all
3879 the customizable options which were changed since that version.
3880 Newly added options are included as well.
3881
3882 If you don't specify a particular version number argument,
3883 then the customization buffer shows all the customizable options
3884 for which Emacs versions of changes are recorded.
3885
3886 This function is also bound to the Changed Options entry in the
3887 Customize menu.
3888
3889 ** When you run M-x grep with a prefix argument, it figures out
3890 the tag around point and puts that into the default grep command.
3891
3892 ** The new command M-* (pop-tag-mark) pops back through a history of
3893 buffer positions from which M-. or other tag-finding commands were
3894 invoked.
3895
3896 ** The new variable comment-padding specifies the number of spaces
3897 that `comment-region' will insert before the actual text of the comment.
3898 The default is 1.
3899
3900 ** In Fortran mode the characters `.', `_' and `$' now have symbol
3901 syntax, not word syntax. Fortran mode now supports `imenu' and has
3902 new commands fortran-join-line (M-^) and fortran-narrow-to-subprogram
3903 (C-x n d). M-q can be used to fill a statement or comment block
3904 sensibly.
3905
3906 ** GUD now supports jdb, the Java debugger, and pdb, the Python debugger.
3907
3908 ** If you set the variable add-log-keep-changes-together to a non-nil
3909 value, the command `C-x 4 a' will automatically notice when you make
3910 two entries in one day for one file, and combine them.
3911
3912 ** You can use the command M-x diary-mail-entries to mail yourself a
3913 reminder about upcoming diary entries. See the documentation string
3914 for a sample shell script for calling this function automatically
3915 every night.
3916
3917 ** Desktop changes
3918
3919 *** All you need to do to enable use of the Desktop package, is to set
3920 the variable desktop-enable to t with Custom.
3921
3922 *** Minor modes are now restored. Which minor modes are restored
3923 and how modes are restored is controlled by `desktop-minor-mode-table'.
3924
3925 ** There is no need to do anything special, now, to enable Gnus to
3926 read and post multi-lingual articles.
3927
3928 ** Outline mode has now support for showing hidden outlines when
3929 doing an isearch. In order for this to happen search-invisible should
3930 be set to open (the default). If an isearch match is inside a hidden
3931 outline the outline is made visible. If you continue pressing C-s and
3932 the match moves outside the formerly invisible outline, the outline is
3933 made invisible again.
3934
3935 ** Mail reading and sending changes
3936
3937 *** The Rmail e command now switches to displaying the whole header of
3938 the message before it lets you edit the message. This is so that any
3939 changes you make in the header will not be lost if you subsequently
3940 toggle.
3941
3942 *** The w command in Rmail, which writes the message body into a file,
3943 now works in the summary buffer as well. (The command to delete the
3944 summary buffer is now Q.) The default file name for the w command, if
3945 the message has no subject, is stored in the variable
3946 rmail-default-body-file.
3947
3948 *** Most of the commands and modes that operate on mail and netnews no
3949 longer depend on the value of mail-header-separator. Instead, they
3950 handle whatever separator the buffer happens to use.
3951
3952 *** If you set mail-signature to a value which is not t, nil, or a string,
3953 it should be an expression. When you send a message, this expression
3954 is evaluated to insert the signature.
3955
3956 *** The new Lisp library feedmail.el (version 8) enhances processing of
3957 outbound email messages. It works in coordination with other email
3958 handling packages (e.g., rmail, VM, gnus) and is responsible for
3959 putting final touches on messages and actually submitting them for
3960 transmission. Users of the emacs program "fakemail" might be
3961 especially interested in trying feedmail.
3962
3963 feedmail is not enabled by default. See comments at the top of
3964 feedmail.el for set-up instructions. Among the bigger features
3965 provided by feedmail are:
3966
3967 **** you can park outgoing messages into a disk-based queue and
3968 stimulate sending some or all of them later (handy for laptop users);
3969 there is also a queue for draft messages
3970
3971 **** you can get one last look at the prepped outbound message and
3972 be prompted for confirmation
3973
3974 **** does smart filling of address headers
3975
3976 **** can generate a MESSAGE-ID: line and a DATE: line; the date can be
3977 the time the message was written or the time it is being sent; this
3978 can make FCC copies more closely resemble copies that recipients get
3979
3980 **** you can specify an arbitrary function for actually transmitting
3981 the message; included in feedmail are interfaces for /bin/[r]mail,
3982 /usr/lib/sendmail, and elisp smtpmail; it's easy to write a new
3983 function for something else (10-20 lines of elisp)
3984
3985 ** Dired changes
3986
3987 *** The Dired function dired-do-toggle, which toggles marked and unmarked
3988 files, is now bound to "t" instead of "T".
3989
3990 *** dired-at-point has been added to ffap.el. It allows one to easily
3991 run Dired on the directory name at point.
3992
3993 *** Dired has a new command: %g. It searches the contents of
3994 files in the directory and marks each file that contains a match
3995 for a specified regexp.
3996
3997 ** VC Changes
3998
3999 *** New option vc-ignore-vc-files lets you turn off version control
4000 conveniently.
4001
4002 *** VC Dired has been completely rewritten. It is now much
4003 faster, especially for CVS, and works very similar to ordinary
4004 Dired.
4005
4006 VC Dired is invoked by typing C-x v d and entering the name of the
4007 directory to display. By default, VC Dired gives you a recursive
4008 listing of all files at or below the given directory which are
4009 currently locked (for CVS, all files not up-to-date are shown).
4010
4011 You can change the listing format by setting vc-dired-recurse to nil,
4012 then it shows only the given directory, and you may also set
4013 vc-dired-terse-display to nil, then it shows all files under version
4014 control plus the names of any subdirectories, so that you can type `i'
4015 on such lines to insert them manually, as in ordinary Dired.
4016
4017 All Dired commands operate normally in VC Dired, except for `v', which
4018 is redefined as the version control prefix. That means you may type
4019 `v l', `v =' etc. to invoke `vc-print-log', `vc-diff' and the like on
4020 the file named in the current Dired buffer line. `v v' invokes
4021 `vc-next-action' on this file, or on all files currently marked.
4022
4023 The new command `v t' (vc-dired-toggle-terse-mode) allows you to
4024 toggle between terse display (only locked files) and full display (all
4025 VC files plus subdirectories). There is also a special command,
4026 `* l', to mark all files currently locked.
4027
4028 Giving a prefix argument to C-x v d now does the same thing as in
4029 ordinary Dired: it allows you to supply additional options for the ls
4030 command in the minibuffer, to fine-tune VC Dired's output.
4031
4032 *** Under CVS, if you merge changes from the repository into a working
4033 file, and CVS detects conflicts, VC now offers to start an ediff
4034 session to resolve them.
4035
4036 Alternatively, you can use the new command `vc-resolve-conflicts' to
4037 resolve conflicts in a file at any time. It works in any buffer that
4038 contains conflict markers as generated by rcsmerge (which is what CVS
4039 uses as well).
4040
4041 *** You can now transfer changes between branches, using the new
4042 command vc-merge (C-x v m). It is implemented for RCS and CVS. When
4043 you invoke it in a buffer under version-control, you can specify
4044 either an entire branch or a pair of versions, and the changes on that
4045 branch or between the two versions are merged into the working file.
4046 If this results in any conflicts, they may be resolved interactively,
4047 using ediff.
4048
4049 ** Changes in Font Lock
4050
4051 *** The face and variable previously known as font-lock-reference-face
4052 are now called font-lock-constant-face to better reflect their typical
4053 use for highlighting constants and labels. (Its face properties are
4054 unchanged.) The variable font-lock-reference-face remains for now for
4055 compatibility reasons, but its value is font-lock-constant-face.
4056
4057 ** Frame name display changes
4058
4059 *** The command set-frame-name lets you set the name of the current
4060 frame. You can use the new command select-frame-by-name to select and
4061 raise a frame; this is mostly useful on character-only terminals, or
4062 when many frames are invisible or iconified.
4063
4064 *** On character-only terminal (not a window system), changing the
4065 frame name is now reflected on the mode line and in the Buffers/Frames
4066 menu.
4067
4068 ** Comint (subshell) changes
4069
4070 *** In Comint modes, the commands to kill, stop or interrupt a
4071 subjob now also kill pending input. This is for compatibility
4072 with ordinary shells, where the signal characters do this.
4073
4074 *** There are new commands in Comint mode.
4075
4076 C-c C-x fetches the "next" line from the input history;
4077 that is, the line after the last line you got.
4078 You can use this command to fetch successive lines, one by one.
4079
4080 C-c SPC accumulates lines of input. More precisely, it arranges to
4081 send the current line together with the following line, when you send
4082 the following line.
4083
4084 C-c C-a if repeated twice consecutively now moves to the process mark,
4085 which separates the pending input from the subprocess output and the
4086 previously sent input.
4087
4088 C-c M-r now runs comint-previous-matching-input-from-input;
4089 it searches for a previous command, using the current pending input
4090 as the search string.
4091
4092 *** New option compilation-scroll-output can be set to scroll
4093 automatically in compilation-mode windows.
4094
4095 ** C mode changes
4096
4097 *** Multiline macros are now handled, both as they affect indentation,
4098 and as recognized syntax. New syntactic symbol cpp-macro-cont is
4099 assigned to second and subsequent lines of a multiline macro
4100 definition.
4101
4102 *** A new style "user" which captures all non-hook-ified
4103 (i.e. top-level) .emacs file variable settings and customizations.
4104 Style "cc-mode" is an alias for "user" and is deprecated. "gnu"
4105 style is still the default however.
4106
4107 *** "java" style now conforms to Sun's JDK coding style.
4108
4109 *** There are new commands c-beginning-of-defun, c-end-of-defun which
4110 are alternatives which you could bind to C-M-a and C-M-e if you prefer
4111 them. They do not have key bindings by default.
4112
4113 *** New and improved implementations of M-a (c-beginning-of-statement)
4114 and M-e (c-end-of-statement).
4115
4116 *** C++ namespace blocks are supported, with new syntactic symbols
4117 namespace-open, namespace-close, and innamespace.
4118
4119 *** File local variable settings of c-file-style and c-file-offsets
4120 makes the style variables local to that buffer only.
4121
4122 *** New indentation functions c-lineup-close-paren,
4123 c-indent-one-line-block, c-lineup-dont-change.
4124
4125 *** Improvements (hopefully!) to the way CC Mode is loaded. You
4126 should now be able to do a (require 'cc-mode) to get the entire
4127 package loaded properly for customization in your .emacs file. A new
4128 variable c-initialize-on-load controls this and is t by default.
4129
4130 ** Changes to hippie-expand.
4131
4132 *** New customization variable `hippie-expand-dabbrev-skip-space'. If
4133 non-nil, trailing spaces may be included in the abbreviation to search for,
4134 which then gives the same behavior as the original `dabbrev-expand'.
4135
4136 *** New customization variable `hippie-expand-dabbrev-as-symbol'. If
4137 non-nil, characters of syntax '_' is considered part of the word when
4138 expanding dynamically.
4139
4140 *** New customization variable `hippie-expand-no-restriction'. If
4141 non-nil, narrowed buffers are widened before they are searched.
4142
4143 *** New customization variable `hippie-expand-only-buffers'. If
4144 non-empty, buffers searched are restricted to the types specified in
4145 this list. Useful for example when constructing new special-purpose
4146 expansion functions with `make-hippie-expand-function'.
4147
4148 *** Text properties of the expansion are no longer copied.
4149
4150 ** Changes in BibTeX mode.
4151
4152 *** Any titleword matching a regexp in the new variable
4153 bibtex-autokey-titleword-ignore (case sensitive) is ignored during
4154 automatic key generation. This replaces variable
4155 bibtex-autokey-titleword-first-ignore, which only checked for matches
4156 against the first word in the title.
4157
4158 *** Autokey generation now uses all words from the title, not just
4159 capitalized words. To avoid conflicts with existing customizations,
4160 bibtex-autokey-titleword-ignore is set up such that words starting with
4161 lowerkey characters will still be ignored. Thus, if you want to use
4162 lowercase words from the title, you will have to overwrite the
4163 bibtex-autokey-titleword-ignore standard setting.
4164
4165 *** Case conversion of names and title words for automatic key
4166 generation is more flexible. Variable bibtex-autokey-preserve-case is
4167 replaced by bibtex-autokey-titleword-case-convert and
4168 bibtex-autokey-name-case-convert.
4169
4170 ** Changes in vcursor.el.
4171
4172 *** Support for character terminals is available: there is a new keymap
4173 and the vcursor will appear as an arrow between buffer text. A
4174 variable `vcursor-interpret-input' allows input from the vcursor to be
4175 entered exactly as if typed. Numerous functions, including
4176 `vcursor-compare-windows', have been rewritten to improve consistency
4177 in the selection of windows and corresponding keymaps.
4178
4179 *** vcursor options can now be altered with M-x customize under the
4180 Editing group once the package is loaded.
4181
4182 *** Loading vcursor now does not define keys by default, as this is
4183 generally a bad side effect. Use M-x customize to set
4184 vcursor-key-bindings to t to restore the old behaviour.
4185
4186 *** vcursor-auto-disable can be `copy', which turns off copying from the
4187 vcursor, but doesn't disable it, after any non-vcursor command.
4188
4189 ** Ispell changes.
4190
4191 *** You can now spell check comments and strings in the current
4192 buffer with M-x ispell-comments-and-strings. Comments and strings
4193 are identified by syntax tables in effect.
4194
4195 *** Generic region skipping implemented.
4196 A single buffer can be broken into a number of regions where text will
4197 and will not be checked. The definitions of the regions can be user
4198 defined. New applications and improvements made available by this
4199 include:
4200
4201 o URLs are automatically skipped
4202 o EMail message checking is vastly improved.
4203
4204 *** Ispell can highlight the erroneous word even on non-window terminals.
4205
4206 ** Changes to RefTeX mode
4207
4208 RefTeX has been updated in order to make it more usable with very
4209 large projects (like a several volume math book). The parser has been
4210 re-written from scratch. To get maximum speed from RefTeX, check the
4211 section `Optimizations' in the manual.
4212
4213 *** New recursive parser.
4214
4215 The old version of RefTeX created a single large buffer containing the
4216 entire multifile document in order to parse the document. The new
4217 recursive parser scans the individual files.
4218
4219 *** Parsing only part of a document.
4220
4221 Reparsing of changed document parts can now be made faster by enabling
4222 partial scans. To use this feature, read the documentation string of
4223 the variable `reftex-enable-partial-scans' and set the variable to t.
4224
4225 (setq reftex-enable-partial-scans t)
4226
4227 *** Storing parsing information in a file.
4228
4229 This can improve startup times considerably. To turn it on, use
4230
4231 (setq reftex-save-parse-info t)
4232
4233 *** Using multiple selection buffers
4234
4235 If the creation of label selection buffers is too slow (this happens
4236 for large documents), you can reuse these buffers by setting
4237
4238 (setq reftex-use-multiple-selection-buffers t)
4239
4240 *** References to external documents.
4241
4242 The LaTeX package `xr' allows to cross-reference labels in external
4243 documents. RefTeX can provide information about the external
4244 documents as well. To use this feature, set up the \externaldocument
4245 macros required by the `xr' package and rescan the document with
4246 RefTeX. The external labels can then be accessed with the `x' key in
4247 the selection buffer provided by `reftex-reference' (bound to `C-c )').
4248 The `x' key also works in the table of contents buffer.
4249
4250 *** Many more labeled LaTeX environments are recognized by default.
4251
4252 The builtin command list now covers all the standard LaTeX commands,
4253 and all of the major packages included in the LaTeX distribution.
4254
4255 Also, RefTeX now understands the \appendix macro and changes
4256 the enumeration of sections in the *toc* buffer accordingly.
4257
4258 *** Mouse support for selection and *toc* buffers
4259
4260 The mouse can now be used to select items in the selection and *toc*
4261 buffers. See also the new option `reftex-highlight-selection'.
4262
4263 *** New keymaps for selection and table of contents modes.
4264
4265 The selection processes for labels and citation keys, and the table of
4266 contents buffer now have their own keymaps: `reftex-select-label-map',
4267 `reftex-select-bib-map', `reftex-toc-map'. The selection processes
4268 have a number of new keys predefined. In particular, TAB lets you
4269 enter a label with completion. Check the on-the-fly help (press `?'
4270 at the selection prompt) or read the Info documentation to find out
4271 more.
4272
4273 *** Support for the varioref package
4274
4275 The `v' key in the label selection buffer toggles \ref versus \vref.
4276
4277 *** New hooks
4278
4279 Three new hooks can be used to redefine the way labels, references,
4280 and citations are created. These hooks are
4281 `reftex-format-label-function', `reftex-format-ref-function',
4282 `reftex-format-cite-function'.
4283
4284 *** Citations outside LaTeX
4285
4286 The command `reftex-citation' may also be used outside LaTeX (e.g. in
4287 a mail buffer). See the Info documentation for details.
4288
4289 *** Short context is no longer fontified.
4290
4291 The short context in the label menu no longer copies the
4292 fontification from the text in the buffer. If you prefer it to be
4293 fontified, use
4294
4295 (setq reftex-refontify-context t)
4296
4297 ** file-cache-minibuffer-complete now accepts a prefix argument.
4298 With a prefix argument, it does not try to do completion of
4299 the file name within its directory; it only checks for other
4300 directories that contain the same file name.
4301
4302 Thus, given the file name Makefile, and assuming that a file
4303 Makefile.in exists in the same directory, ordinary
4304 file-cache-minibuffer-complete will try to complete Makefile to
4305 Makefile.in and will therefore never look for other directories that
4306 have Makefile. A prefix argument tells it not to look for longer
4307 names such as Makefile.in, so that instead it will look for other
4308 directories--just as if the name were already complete in its present
4309 directory.
4310
4311 ** New modes and packages
4312
4313 *** There is a new alternative major mode for Perl, Cperl mode.
4314 It has many more features than Perl mode, and some people prefer
4315 it, but some do not.
4316
4317 *** There is a new major mode, M-x vhdl-mode, for editing files of VHDL
4318 code.
4319
4320 *** M-x which-function-mode enables a minor mode that displays the
4321 current function name continuously in the mode line, as you move
4322 around in a buffer.
4323
4324 Which Function mode is effective in major modes which support Imenu.
4325
4326 *** Gametree is a major mode for editing game analysis trees. The author
4327 uses it for keeping notes about his postal Chess games, but it should
4328 be helpful for other two-player games as well, as long as they have an
4329 established system of notation similar to Chess.
4330
4331 *** The new minor mode checkdoc-minor-mode provides Emacs Lisp
4332 documentation string checking for style and spelling. The style
4333 guidelines are found in the Emacs Lisp programming manual.
4334
4335 *** The net-utils package makes some common networking features
4336 available in Emacs. Some of these functions are wrappers around
4337 system utilities (ping, nslookup, etc); others are implementations of
4338 simple protocols (finger, whois) in Emacs Lisp. There are also
4339 functions to make simple connections to TCP/IP ports for debugging and
4340 the like.
4341
4342 *** highlight-changes-mode is a minor mode that uses colors to
4343 identify recently changed parts of the buffer text.
4344
4345 *** The new package `midnight' lets you specify things to be done
4346 within Emacs at midnight--by default, kill buffers that you have not
4347 used in a considerable time. To use this feature, customize
4348 the user option `midnight-mode' to t.
4349
4350 *** The file generic-x.el defines a number of simple major modes.
4351
4352 apache-generic-mode: For Apache and NCSA httpd configuration files
4353 samba-generic-mode: Samba configuration files
4354 fvwm-generic-mode: For fvwm initialization files
4355 x-resource-generic-mode: For X resource files
4356 hosts-generic-mode: For hosts files (.rhosts, /etc/hosts, etc)
4357 mailagent-rules-generic-mode: For mailagent .rules files
4358 javascript-generic-mode: For JavaScript files
4359 vrml-generic-mode: For VRML files
4360 java-manifest-generic-mode: For Java MANIFEST files
4361 java-properties-generic-mode: For Java property files
4362 mailrc-generic-mode: For .mailrc files
4363
4364 Platform-specific modes:
4365
4366 prototype-generic-mode: For Solaris/Sys V prototype files
4367 pkginfo-generic-mode: For Solaris/Sys V pkginfo files
4368 alias-generic-mode: For C shell alias files
4369 inf-generic-mode: For MS-Windows INF files
4370 ini-generic-mode: For MS-Windows INI files
4371 reg-generic-mode: For MS-Windows Registry files
4372 bat-generic-mode: For MS-Windows BAT scripts
4373 rc-generic-mode: For MS-Windows Resource files
4374 rul-generic-mode: For InstallShield scripts
4375 \f
4376 * Lisp changes in Emacs 20.3 since the Emacs Lisp Manual was published
4377
4378 ** If you want a Lisp file to be read in unibyte mode,
4379 use -*-unibyte: t;-*- on its first line.
4380 That will force Emacs to read that file in unibyte mode.
4381 Otherwise, the file will be loaded and byte-compiled in multibyte mode.
4382
4383 Thus, each lisp file is read in a consistent way regardless of whether
4384 you started Emacs with --unibyte, so that a Lisp program gives
4385 consistent results regardless of how Emacs was started.
4386
4387 ** The new function assoc-default is useful for searching an alist,
4388 and using a default value if the key is not found there. You can
4389 specify a comparison predicate, so this function is useful for
4390 searching comparing a string against an alist of regular expressions.
4391
4392 ** The functions unibyte-char-to-multibyte and
4393 multibyte-char-to-unibyte convert between unibyte and multibyte
4394 character codes, in a way that is appropriate for the current language
4395 environment.
4396
4397 ** The functions read-event, read-char and read-char-exclusive now
4398 take two optional arguments. PROMPT, if non-nil, specifies a prompt
4399 string. SUPPRESS-INPUT-METHOD, if non-nil, says to disable the
4400 current input method for reading this one event.
4401
4402 ** Two new variables print-escape-nonascii and print-escape-multibyte
4403 now control whether to output certain characters as
4404 backslash-sequences. print-escape-nonascii applies to single-byte
4405 non-ASCII characters; print-escape-multibyte applies to multibyte
4406 characters. Both of these variables are used only when printing
4407 in readable fashion (prin1 uses them, princ does not).
4408 \f
4409 * Lisp changes in Emacs 20.3 before the Emacs Lisp Manual was published
4410
4411 ** Compiled Emacs Lisp files made with the modified "MBSK" version
4412 of Emacs 20.2 do not work in Emacs 20.3.
4413
4414 ** Buffer positions are now measured in characters, as they were
4415 in Emacs 19 and before. This means that (forward-char 1)
4416 always increases point by 1.
4417
4418 The function chars-in-region now just subtracts its arguments. It is
4419 considered obsolete. The function char-boundary-p has been deleted.
4420
4421 See below for additional changes relating to multibyte characters.
4422
4423 ** defcustom, defface and defgroup now accept the keyword `:version'.
4424 Use this to specify in which version of Emacs a certain variable's
4425 default value changed. For example,
4426
4427 (defcustom foo-max 34 "*Maximum number of foo's allowed."
4428 :type 'integer
4429 :group 'foo
4430 :version "20.3")
4431
4432 (defgroup foo-group nil "The foo group."
4433 :version "20.3")
4434
4435 If an entire new group is added or the variables in it have the
4436 default values changed, then just add a `:version' to that group. It
4437 is recommended that new packages added to the distribution contain a
4438 `:version' in the top level group.
4439
4440 This information is used to control the customize-changed-options command.
4441
4442 ** It is now an error to change the value of a symbol whose name
4443 starts with a colon--if it is interned in the standard obarray.
4444
4445 However, setting such a symbol to its proper value, which is that
4446 symbol itself, is not an error. This is for the sake of programs that
4447 support previous Emacs versions by explicitly setting these variables
4448 to themselves.
4449
4450 If you set the variable keyword-symbols-constant-flag to nil,
4451 this error is suppressed, and you can set these symbols to any
4452 values whatever.
4453
4454 ** There is a new debugger command, R.
4455 It evaluates an expression like e, but saves the result
4456 in the buffer *Debugger-record*.
4457
4458 ** Frame-local variables.
4459
4460 You can now make a variable local to various frames. To do this, call
4461 the function make-variable-frame-local; this enables frames to have
4462 local bindings for that variable.
4463
4464 These frame-local bindings are actually frame parameters: you create a
4465 frame-local binding in a specific frame by calling
4466 modify-frame-parameters and specifying the variable name as the
4467 parameter name.
4468
4469 Buffer-local bindings take precedence over frame-local bindings.
4470 Thus, if the current buffer has a buffer-local binding, that binding is
4471 active; otherwise, if the selected frame has a frame-local binding,
4472 that binding is active; otherwise, the default binding is active.
4473
4474 It would not be hard to implement window-local bindings, but it is not
4475 clear that this would be very useful; windows tend to come and go in a
4476 very transitory fashion, so that trying to produce any specific effect
4477 through a window-local binding would not be very robust.
4478
4479 ** `sregexq' and `sregex' are two new functions for constructing
4480 "symbolic regular expressions." These are Lisp expressions that, when
4481 evaluated, yield conventional string-based regexps. The symbolic form
4482 makes it easier to construct, read, and maintain complex patterns.
4483 See the documentation in sregex.el.
4484
4485 ** parse-partial-sexp's return value has an additional element which
4486 is used to pass information along if you pass it to another call to
4487 parse-partial-sexp, starting its scan where the first call ended.
4488 The contents of this field are not yet finalized.
4489
4490 ** eval-region now accepts a fourth optional argument READ-FUNCTION.
4491 If it is non-nil, that function is used instead of `read'.
4492
4493 ** unload-feature by default removes the feature's functions from
4494 known hooks to avoid trouble, but a package providing FEATURE can
4495 define a hook FEATURE-unload-hook to be run by unload-feature instead.
4496
4497 ** read-from-minibuffer no longer returns the argument DEFAULT-VALUE
4498 when the user enters empty input. It now returns the null string, as
4499 it did in Emacs 19. The default value is made available in the
4500 history via M-n, but it is not applied here as a default.
4501
4502 The other, more specialized minibuffer-reading functions continue to
4503 return the default value (not the null string) when the user enters
4504 empty input.
4505
4506 ** The new variable read-buffer-function controls which routine to use
4507 for selecting buffers. For example, if you set this variable to
4508 `iswitchb-read-buffer', iswitchb will be used to read buffer names.
4509 Other functions can also be used if they accept the same arguments as
4510 `read-buffer' and return the selected buffer name as a string.
4511
4512 ** The new function read-passwd reads a password from the terminal,
4513 echoing a period for each character typed. It takes three arguments:
4514 a prompt string, a flag which says "read it twice to make sure", and a
4515 default password to use if the user enters nothing.
4516
4517 ** The variable fill-nobreak-predicate gives major modes a way to
4518 specify not to break a line at certain places. Its value is a
4519 function which is called with no arguments, with point located at the
4520 place where a break is being considered. If the function returns
4521 non-nil, then the line won't be broken there.
4522
4523 ** window-end now takes an optional second argument, UPDATE.
4524 If this is non-nil, then the function always returns an accurate
4525 up-to-date value for the buffer position corresponding to the
4526 end of the window, even if this requires computation.
4527
4528 ** other-buffer now takes an optional argument FRAME
4529 which specifies which frame's buffer list to use.
4530 If it is nil, that means use the selected frame's buffer list.
4531
4532 ** The new variable buffer-display-time, always local in every buffer,
4533 holds the value of (current-time) as of the last time that a window
4534 was directed to display this buffer.
4535
4536 ** It is now meaningful to compare two window-configuration objects
4537 with `equal'. Two window-configuration objects are equal if they
4538 describe equivalent arrangements of windows, in the same frame--in
4539 other words, if they would give the same results if passed to
4540 set-window-configuration.
4541
4542 ** compare-window-configurations is a new function that compares two
4543 window configurations loosely. It ignores differences in saved buffer
4544 positions and scrolling, and considers only the structure and sizes of
4545 windows and the choice of buffers to display.
4546
4547 ** The variable minor-mode-overriding-map-alist allows major modes to
4548 override the key bindings of a minor mode. The elements of this alist
4549 look like the elements of minor-mode-map-alist: (VARIABLE . KEYMAP).
4550
4551 If the VARIABLE in an element of minor-mode-overriding-map-alist has a
4552 non-nil value, the paired KEYMAP is active, and totally overrides the
4553 map (if any) specified for the same variable in minor-mode-map-alist.
4554
4555 minor-mode-overriding-map-alist is automatically local in all buffers,
4556 and it is meant to be set by major modes.
4557
4558 ** The function match-string-no-properties is like match-string
4559 except that it discards all text properties from the result.
4560
4561 ** The function load-average now accepts an optional argument
4562 USE-FLOATS. If it is non-nil, the load average values are returned as
4563 floating point numbers, rather than as integers to be divided by 100.
4564
4565 ** The new variable temporary-file-directory specifies the directory
4566 to use for creating temporary files. The default value is determined
4567 in a reasonable way for your operating system; on GNU and Unix systems
4568 it is based on the TMP and TMPDIR environment variables.
4569
4570 ** Menu changes
4571
4572 *** easymenu.el now uses the new menu item format and supports the
4573 keywords :visible and :filter. The existing keyword :keys is now
4574 better supported.
4575
4576 The variable `easy-menu-precalculate-equivalent-keybindings' controls
4577 a new feature which calculates keyboard equivalents for the menu when
4578 you define the menu. The default is t. If you rarely use menus, you
4579 can set the variable to nil to disable this precalculation feature;
4580 then the calculation is done only if you use the menu bar.
4581
4582 *** A new format for menu items is supported.
4583
4584 In a keymap, a key binding that has the format
4585 (STRING . REAL-BINDING) or (STRING HELP-STRING . REAL-BINDING)
4586 defines a menu item. Now a menu item definition may also be a list that
4587 starts with the symbol `menu-item'.
4588
4589 The format is:
4590 (menu-item ITEM-NAME) or
4591 (menu-item ITEM-NAME REAL-BINDING . ITEM-PROPERTY-LIST)
4592 where ITEM-NAME is an expression which evaluates to the menu item
4593 string, and ITEM-PROPERTY-LIST has the form of a property list.
4594 The supported properties include
4595
4596 :enable FORM Evaluate FORM to determine whether the
4597 item is enabled.
4598 :visible FORM Evaluate FORM to determine whether the
4599 item should appear in the menu.
4600 :filter FILTER-FN
4601 FILTER-FN is a function of one argument,
4602 which will be REAL-BINDING.
4603 It should return a binding to use instead.
4604 :keys DESCRIPTION
4605 DESCRIPTION is a string that describes an equivalent keyboard
4606 binding for for REAL-BINDING. DESCRIPTION is expanded with
4607 `substitute-command-keys' before it is used.
4608 :key-sequence KEY-SEQUENCE
4609 KEY-SEQUENCE is a key-sequence for an equivalent
4610 keyboard binding.
4611 :key-sequence nil
4612 This means that the command normally has no
4613 keyboard equivalent.
4614 :help HELP HELP is the extra help string (not currently used).
4615 :button (TYPE . SELECTED)
4616 TYPE is :toggle or :radio.
4617 SELECTED is a form, to be evaluated, and its
4618 value says whether this button is currently selected.
4619
4620 Buttons are at the moment only simulated by prefixes in the menu.
4621 Eventually ordinary X-buttons may be supported.
4622
4623 (menu-item ITEM-NAME) defines unselectable item.
4624
4625 ** New event types
4626
4627 *** The new event type `mouse-wheel' is generated by a wheel on a
4628 mouse (such as the MS Intellimouse). The event contains a delta that
4629 corresponds to the amount and direction that the wheel is rotated,
4630 which is typically used to implement a scroll or zoom. The format is:
4631
4632 (mouse-wheel POSITION DELTA)
4633
4634 where POSITION is a list describing the position of the event in the
4635 same format as a mouse-click event, and DELTA is a signed number
4636 indicating the number of increments by which the wheel was rotated. A
4637 negative DELTA indicates that the wheel was rotated backwards, towards
4638 the user, and a positive DELTA indicates that the wheel was rotated
4639 forward, away from the user.
4640
4641 As of now, this event type is generated only on MS Windows.
4642
4643 *** The new event type `drag-n-drop' is generated when a group of
4644 files is selected in an application outside of Emacs, and then dragged
4645 and dropped onto an Emacs frame. The event contains a list of
4646 filenames that were dragged and dropped, which are then typically
4647 loaded into Emacs. The format is:
4648
4649 (drag-n-drop POSITION FILES)
4650
4651 where POSITION is a list describing the position of the event in the
4652 same format as a mouse-click event, and FILES is the list of filenames
4653 that were dragged and dropped.
4654
4655 As of now, this event type is generated only on MS Windows.
4656
4657 ** Changes relating to multibyte characters.
4658
4659 *** The variable enable-multibyte-characters is now read-only;
4660 any attempt to set it directly signals an error. The only way
4661 to change this value in an existing buffer is with set-buffer-multibyte.
4662
4663 *** In a string constant, `\ ' now stands for "nothing at all". You
4664 can use it to terminate a hex escape which is followed by a character
4665 that could otherwise be read as part of the hex escape.
4666
4667 *** String indices are now measured in characters, as they were
4668 in Emacs 19 and before.
4669
4670 The function chars-in-string has been deleted.
4671 The function concat-chars has been renamed to `string'.
4672
4673 *** The function set-buffer-multibyte sets the flag in the current
4674 buffer that says whether the buffer uses multibyte representation or
4675 unibyte representation. If the argument is nil, it selects unibyte
4676 representation. Otherwise it selects multibyte representation.
4677
4678 This function does not change the contents of the buffer, viewed
4679 as a sequence of bytes. However, it does change the contents
4680 viewed as characters; a sequence of two bytes which is treated as
4681 one character when the buffer uses multibyte representation
4682 will count as two characters using unibyte representation.
4683
4684 This function sets enable-multibyte-characters to record which
4685 representation is in use. It also adjusts various data in the buffer
4686 (including its markers, overlays and text properties) so that they are
4687 consistent with the new representation.
4688
4689 *** string-make-multibyte takes a string and converts it to multibyte
4690 representation. Most of the time, you don't need to care
4691 about the representation, because Emacs converts when necessary;
4692 however, it makes a difference when you compare strings.
4693
4694 The conversion of non-ASCII characters works by adding the value of
4695 nonascii-insert-offset to each character, or by translating them
4696 using the table nonascii-translation-table.
4697
4698 *** string-make-unibyte takes a string and converts it to unibyte
4699 representation. Most of the time, you don't need to care about the
4700 representation, but it makes a difference when you compare strings.
4701
4702 The conversion from multibyte to unibyte representation
4703 loses information; the only time Emacs performs it automatically
4704 is when inserting a multibyte string into a unibyte buffer.
4705
4706 *** string-as-multibyte takes a string, and returns another string
4707 which contains the same bytes, but treats them as multibyte.
4708
4709 *** string-as-unibyte takes a string, and returns another string
4710 which contains the same bytes, but treats them as unibyte.
4711
4712 *** The new function compare-strings lets you compare
4713 portions of two strings. Unibyte strings are converted to multibyte,
4714 so that a unibyte string can match a multibyte string.
4715 You can specify whether to ignore case or not.
4716
4717 *** assoc-ignore-case now uses compare-strings so that
4718 it can treat unibyte and multibyte strings as equal.
4719
4720 *** Regular expression operations and buffer string searches now
4721 convert the search pattern to multibyte or unibyte to accord with the
4722 buffer or string being searched.
4723
4724 One consequence is that you cannot always use \200-\377 inside of
4725 [...] to match all non-ASCII characters. This does still work when
4726 searching or matching a unibyte buffer or string, but not when
4727 searching or matching a multibyte string. Unfortunately, there is no
4728 obvious choice of syntax to use within [...] for that job. But, what
4729 you want is just to match all non-ASCII characters, the regular
4730 expression [^\0-\177] works for it.
4731
4732 *** Structure of coding system changed.
4733
4734 All coding systems (including aliases and subsidiaries) are named
4735 by symbols; the symbol's `coding-system' property is a vector
4736 which defines the coding system. Aliases share the same vector
4737 as the principal name, so that altering the contents of this
4738 vector affects the principal name and its aliases. You can define
4739 your own alias name of a coding system by the function
4740 define-coding-system-alias.
4741
4742 The coding system definition includes a property list of its own. Use
4743 the new functions `coding-system-get' and `coding-system-put' to
4744 access such coding system properties as post-read-conversion,
4745 pre-write-conversion, character-translation-table-for-decode,
4746 character-translation-table-for-encode, mime-charset, and
4747 safe-charsets. For instance, (coding-system-get 'iso-latin-1
4748 'mime-charset) gives the corresponding MIME-charset parameter
4749 `iso-8859-1'.
4750
4751 Among the coding system properties listed above, safe-charsets is new.
4752 The value of this property is a list of character sets which this
4753 coding system can correctly encode and decode. For instance:
4754 (coding-system-get 'iso-latin-1 'safe-charsets) => (ascii latin-iso8859-1)
4755
4756 Here, "correctly encode" means that the encoded character sets can
4757 also be handled safely by systems other than Emacs as far as they
4758 are capable of that coding system. Though, Emacs itself can encode
4759 the other character sets and read it back correctly.
4760
4761 *** The new function select-safe-coding-system can be used to find a
4762 proper coding system for encoding the specified region or string.
4763 This function requires a user interaction.
4764
4765 *** The new functions find-coding-systems-region and
4766 find-coding-systems-string are helper functions used by
4767 select-safe-coding-system. They return a list of all proper coding
4768 systems to encode a text in some region or string. If you don't want
4769 a user interaction, use one of these functions instead of
4770 select-safe-coding-system.
4771
4772 *** The explicit encoding and decoding functions, such as
4773 decode-coding-region and encode-coding-string, now set
4774 last-coding-system-used to reflect the actual way encoding or decoding
4775 was done.
4776
4777 *** The new function detect-coding-with-language-environment can be
4778 used to detect a coding system of text according to priorities of
4779 coding systems used by some specific language environment.
4780
4781 *** The functions detect-coding-region and detect-coding-string always
4782 return a list if the arg HIGHEST is nil. Thus, if only ASCII
4783 characters are found, they now return a list of single element
4784 `undecided' or its subsidiaries.
4785
4786 *** The new functions coding-system-change-eol-conversion and
4787 coding-system-change-text-conversion can be used to get a different
4788 coding system than what specified only in how end-of-line or text is
4789 converted.
4790
4791 *** The new function set-selection-coding-system can be used to set a
4792 coding system for communicating with other X clients.
4793
4794 *** The function `map-char-table' now passes as argument only valid
4795 character codes, plus generic characters that stand for entire
4796 character sets or entire subrows of a character set. In other words,
4797 each time `map-char-table' calls its FUNCTION argument, the key value
4798 either will be a valid individual character code, or will stand for a
4799 range of characters.
4800
4801 *** The new function `char-valid-p' can be used for checking whether a
4802 Lisp object is a valid character code or not.
4803
4804 *** The new function `charset-after' returns a charset of a character
4805 in the current buffer at position POS.
4806
4807 *** Input methods are now implemented using the variable
4808 input-method-function. If this is non-nil, its value should be a
4809 function; then, whenever Emacs reads an input event that is a printing
4810 character with no modifier bits, it calls that function, passing the
4811 event as an argument. Often this function will read more input, first
4812 binding input-method-function to nil.
4813
4814 The return value should be a list of the events resulting from input
4815 method processing. These events will be processed sequentially as
4816 input, before resorting to unread-command-events. Events returned by
4817 the input method function are not passed to the input method function,
4818 not even if they are printing characters with no modifier bits.
4819
4820 The input method function is not called when reading the second and
4821 subsequent events of a key sequence.
4822
4823 *** You can customize any language environment by using
4824 set-language-environment-hook and exit-language-environment-hook.
4825
4826 The hook `exit-language-environment-hook' should be used to undo
4827 customizations that you made with set-language-environment-hook. For
4828 instance, if you set up a special key binding for a specific language
4829 environment by set-language-environment-hook, you should set up
4830 exit-language-environment-hook to restore the normal key binding.
4831 \f
4832 * Changes in Emacs 20.1
4833
4834 ** Emacs has a new facility for customization of its many user
4835 options. It is called M-x customize. With this facility you can look
4836 at the many user options in an organized way; they are grouped into a
4837 tree structure.
4838
4839 M-x customize also knows what sorts of values are legitimate for each
4840 user option and ensures that you don't use invalid values.
4841
4842 With M-x customize, you can set options either for the present Emacs
4843 session or permanently. (Permanent settings are stored automatically
4844 in your .emacs file.)
4845
4846 ** Scroll bars are now on the left side of the window.
4847 You can change this with M-x customize-option scroll-bar-mode.
4848
4849 ** The mode line no longer includes the string `Emacs'.
4850 This makes more space in the mode line for other information.
4851
4852 ** When you select a region with the mouse, it is highlighted
4853 immediately afterward. At that time, if you type the DELETE key, it
4854 kills the region.
4855
4856 The BACKSPACE key, and the ASCII character DEL, do not do this; they
4857 delete the character before point, as usual.
4858
4859 ** In an incremental search the whole current match is highlighted
4860 on terminals which support this. (You can disable this feature
4861 by setting search-highlight to nil.)
4862
4863 ** In the minibuffer, in some cases, you can now use M-n to
4864 insert the default value into the minibuffer as text. In effect,
4865 the default value (if the minibuffer routines know it) is tacked
4866 onto the history "in the future". (The more normal use of the
4867 history list is to use M-p to insert minibuffer input used in the
4868 past.)
4869
4870 ** In Text mode, now only blank lines separate paragraphs.
4871 This makes it possible to get the full benefit of Adaptive Fill mode
4872 in Text mode, and other modes derived from it (such as Mail mode).
4873 TAB in Text mode now runs the command indent-relative; this
4874 makes a practical difference only when you use indented paragraphs.
4875
4876 As a result, the old Indented Text mode is now identical to Text mode,
4877 and is an alias for it.
4878
4879 If you want spaces at the beginning of a line to start a paragraph,
4880 use the new mode, Paragraph Indent Text mode.
4881
4882 ** Scrolling changes
4883
4884 *** Scroll commands to scroll a whole screen now preserve the screen
4885 position of the cursor, if scroll-preserve-screen-position is non-nil.
4886
4887 In this mode, if you scroll several screens back and forth, finishing
4888 on the same screen where you started, the cursor goes back to the line
4889 where it started.
4890
4891 *** If you set scroll-conservatively to a small number, then when you
4892 move point a short distance off the screen, Emacs will scroll the
4893 screen just far enough to bring point back on screen, provided that
4894 does not exceed `scroll-conservatively' lines.
4895
4896 *** The new variable scroll-margin says how close point can come to the
4897 top or bottom of a window. It is a number of screen lines; if point
4898 comes within that many lines of the top or bottom of the window, Emacs
4899 recenters the window.
4900
4901 ** International character set support (MULE)
4902
4903 Emacs now supports a wide variety of international character sets,
4904 including European variants of the Latin alphabet, as well as Chinese,
4905 Devanagari (Hindi and Marathi), Ethiopian, Greek, IPA, Japanese,
4906 Korean, Lao, Russian, Thai, Tibetan, and Vietnamese scripts. These
4907 features have been merged from the modified version of Emacs known as
4908 MULE (for "MULti-lingual Enhancement to GNU Emacs")
4909
4910 Users of these scripts have established many more-or-less standard
4911 coding systems for storing files. Emacs uses a single multibyte
4912 character encoding within Emacs buffers; it can translate from a wide
4913 variety of coding systems when reading a file and can translate back
4914 into any of these coding systems when saving a file.
4915
4916 Keyboards, even in the countries where these character sets are used,
4917 generally don't have keys for all the characters in them. So Emacs
4918 supports various "input methods", typically one for each script or
4919 language, to make it possible to type them.
4920
4921 The Emacs internal multibyte encoding represents a non-ASCII
4922 character as a sequence of bytes in the range 0200 through 0377.
4923
4924 The new prefix key C-x RET is used for commands that pertain
4925 to multibyte characters, coding systems, and input methods.
4926
4927 You can disable multibyte character support as follows:
4928
4929 (setq-default enable-multibyte-characters nil)
4930
4931 Calling the function standard-display-european turns off multibyte
4932 characters, unless you specify a non-nil value for the second
4933 argument, AUTO. This provides compatibility for people who are
4934 already using standard-display-european to continue using unibyte
4935 characters for their work until they want to change.
4936
4937 *** Input methods
4938
4939 An input method is a kind of character conversion which is designed
4940 specifically for interactive input. In Emacs, typically each language
4941 has its own input method (though sometimes several languages which use
4942 the same characters can share one input method). Some languages
4943 support several input methods.
4944
4945 The simplest kind of input method works by mapping ASCII letters into
4946 another alphabet. This is how the Greek and Russian input methods
4947 work.
4948
4949 A more powerful technique is composition: converting sequences of
4950 characters into one letter. Many European input methods use
4951 composition to produce a single non-ASCII letter from a sequence which
4952 consists of a letter followed by diacritics. For example, a' is one
4953 sequence of two characters that might be converted into a single
4954 letter.
4955
4956 The input methods for syllabic scripts typically use mapping followed
4957 by conversion. The input methods for Thai and Korean work this way.
4958 First, letters are mapped into symbols for particular sounds or tone
4959 marks; then, sequences of these which make up a whole syllable are
4960 mapped into one syllable sign--most often a "composite character".
4961
4962 None of these methods works very well for Chinese and Japanese, so
4963 they are handled specially. First you input a whole word using
4964 phonetic spelling; then, after the word is in the buffer, Emacs
4965 converts it into one or more characters using a large dictionary.
4966
4967 Since there is more than one way to represent a phonetically spelled
4968 word using Chinese characters, Emacs can only guess which one to use;
4969 typically these input methods give you a way to say "guess again" if
4970 the first guess is wrong.
4971
4972 *** The command C-x RET m (toggle-enable-multibyte-characters)
4973 turns multibyte character support on or off for the current buffer.
4974
4975 If multibyte character support is turned off in a buffer, then each
4976 byte is a single character, even codes 0200 through 0377--exactly as
4977 they did in Emacs 19.34. This includes the features for support for
4978 the European characters, ISO Latin-1 and ISO Latin-2.
4979
4980 However, there is no need to turn off multibyte character support to
4981 use ISO Latin-1 or ISO Latin-2; the Emacs multibyte character set
4982 includes all the characters in these character sets, and Emacs can
4983 translate automatically to and from either one.
4984
4985 *** Visiting a file in unibyte mode.
4986
4987 Turning off multibyte character support in the buffer after visiting a
4988 file with multibyte code conversion will display the multibyte
4989 sequences already in the buffer, byte by byte. This is probably not
4990 what you want.
4991
4992 If you want to edit a file of unibyte characters (Latin-1, for
4993 example), you can do it by specifying `no-conversion' as the coding
4994 system when reading the file. This coding system also turns off
4995 multibyte characters in that buffer.
4996
4997 If you turn off multibyte character support entirely, this turns off
4998 character conversion as well.
4999
5000 *** Displaying international characters on X Windows.
5001
5002 A font for X typically displays just one alphabet or script.
5003 Therefore, displaying the entire range of characters Emacs supports
5004 requires using many fonts.
5005
5006 Therefore, Emacs now supports "fontsets". Each fontset is a
5007 collection of fonts, each assigned to a range of character codes.
5008
5009 A fontset has a name, like a font. Individual fonts are defined by
5010 the X server; fontsets are defined within Emacs itself. But once you
5011 have defined a fontset, you can use it in a face or a frame just as
5012 you would use a font.
5013
5014 If a fontset specifies no font for a certain character, or if it
5015 specifies a font that does not exist on your system, then it cannot
5016 display that character. It will display an empty box instead.
5017
5018 The fontset height and width are determined by the ASCII characters
5019 (that is, by the font in the fontset which is used for ASCII
5020 characters). If another font in the fontset has a different height,
5021 or the wrong width, then characters assigned to that font are clipped,
5022 and displayed within a box if highlight-wrong-size-font is non-nil.
5023
5024 *** Defining fontsets.
5025
5026 Emacs does not use any fontset by default. Its default font is still
5027 chosen as in previous versions. You can tell Emacs to use a fontset
5028 with the `-fn' option or the `Font' X resource.
5029
5030 Emacs creates a standard fontset automatically according to the value
5031 of standard-fontset-spec. This fontset's short name is
5032 `fontset-standard'. Bold, italic, and bold-italic variants of the
5033 standard fontset are created automatically.
5034
5035 If you specify a default ASCII font with the `Font' resource or `-fn'
5036 argument, a fontset is generated from it. This works by replacing the
5037 FOUNDARY, FAMILY, ADD_STYLE, and AVERAGE_WIDTH fields of the font name
5038 with `*' then using this to specify a fontset. This fontset's short
5039 name is `fontset-startup'.
5040
5041 Emacs checks resources of the form Fontset-N where N is 0, 1, 2...
5042 The resource value should have this form:
5043 FONTSET-NAME, [CHARSET-NAME:FONT-NAME]...
5044 FONTSET-NAME should have the form of a standard X font name, except:
5045 * most fields should be just the wild card "*".
5046 * the CHARSET_REGISTRY field should be "fontset"
5047 * the CHARSET_ENCODING field can be any nickname of the fontset.
5048 The construct CHARSET-NAME:FONT-NAME can be repeated any number
5049 of times; each time specifies the font for one character set.
5050 CHARSET-NAME should be the name name of a character set, and
5051 FONT-NAME should specify an actual font to use for that character set.
5052
5053 Each of these fontsets has an alias which is made from the
5054 last two font name fields, CHARSET_REGISTRY and CHARSET_ENCODING.
5055 You can refer to the fontset by that alias or by its full name.
5056
5057 For any character sets that you don't mention, Emacs tries to choose a
5058 font by substituting into FONTSET-NAME. For instance, with the
5059 following resource,
5060 Emacs*Fontset-0: -*-fixed-medium-r-normal-*-24-*-*-*-*-*-fontset-24
5061 the font for ASCII is generated as below:
5062 -*-fixed-medium-r-normal-*-24-*-ISO8859-1
5063 Here is the substitution rule:
5064 Change CHARSET_REGISTRY and CHARSET_ENCODING to that of the charset
5065 defined in the variable x-charset-registries. For instance, ASCII has
5066 the entry (ascii . "ISO8859-1") in this variable. Then, reduce
5067 sequences of wild cards -*-...-*- with a single wildcard -*-.
5068 (This is to prevent use of auto-scaled fonts.)
5069
5070 The function which processes the fontset resource value to create the
5071 fontset is called create-fontset-from-fontset-spec. You can also call
5072 that function explicitly to create a fontset.
5073
5074 With the X resource Emacs.Font, you can specify a fontset name just
5075 like an actual font name. But be careful not to specify a fontset
5076 name in a wildcard resource like Emacs*Font--that tries to specify the
5077 fontset for other purposes including menus, and they cannot handle
5078 fontsets.
5079
5080 *** The command M-x set-language-environment sets certain global Emacs
5081 defaults for a particular choice of language.
5082
5083 Selecting a language environment typically specifies a default input
5084 method and which coding systems to recognize automatically when
5085 visiting files. However, it does not try to reread files you have
5086 already visited; the text in those buffers is not affected. The
5087 language environment may also specify a default choice of coding
5088 system for new files that you create.
5089
5090 It makes no difference which buffer is current when you use
5091 set-language-environment, because these defaults apply globally to the
5092 whole Emacs session.
5093
5094 For example, M-x set-language-environment RET Latin-1 RET
5095 chooses the Latin-1 character set. In the .emacs file, you can do this
5096 with (set-language-environment "Latin-1").
5097
5098 *** The command C-x RET f (set-buffer-file-coding-system)
5099 specifies the file coding system for the current buffer. This
5100 specifies what sort of character code translation to do when saving
5101 the file. As an argument, you must specify the name of one of the
5102 coding systems that Emacs supports.
5103
5104 *** The command C-x RET c (universal-coding-system-argument)
5105 lets you specify a coding system when you read or write a file.
5106 This command uses the minibuffer to read a coding system name.
5107 After you exit the minibuffer, the specified coding system
5108 is used for *the immediately following command*.
5109
5110 So if the immediately following command is a command to read or
5111 write a file, it uses the specified coding system for that file.
5112
5113 If the immediately following command does not use the coding system,
5114 then C-x RET c ultimately has no effect.
5115
5116 For example, C-x RET c iso-8859-1 RET C-x C-f temp RET
5117 visits the file `temp' treating it as ISO Latin-1.
5118
5119 *** You can specify the coding system for a file using the -*-
5120 construct. Include `coding: CODINGSYSTEM;' inside the -*-...-*-
5121 to specify use of coding system CODINGSYSTEM. You can also
5122 specify the coding system in a local variable list at the end
5123 of the file.
5124
5125 *** The command C-x RET t (set-terminal-coding-system) specifies
5126 the coding system for terminal output. If you specify a character
5127 code for terminal output, all characters output to the terminal are
5128 translated into that character code.
5129
5130 This feature is useful for certain character-only terminals built in
5131 various countries to support the languages of those countries.
5132
5133 By default, output to the terminal is not translated at all.
5134
5135 *** The command C-x RET k (set-keyboard-coding-system) specifies
5136 the coding system for keyboard input.
5137
5138 Character code translation of keyboard input is useful for terminals
5139 with keys that send non-ASCII graphic characters--for example,
5140 some terminals designed for ISO Latin-1 or subsets of it.
5141
5142 By default, keyboard input is not translated at all.
5143
5144 Character code translation of keyboard input is similar to using an
5145 input method, in that both define sequences of keyboard input that
5146 translate into single characters. However, input methods are designed
5147 to be convenient for interactive use, while the code translations are
5148 designed to work with terminals.
5149
5150 *** The command C-x RET p (set-buffer-process-coding-system)
5151 specifies the coding system for input and output to a subprocess.
5152 This command applies to the current buffer; normally, each subprocess
5153 has its own buffer, and thus you can use this command to specify
5154 translation to and from a particular subprocess by giving the command
5155 in the corresponding buffer.
5156
5157 By default, process input and output are not translated at all.
5158
5159 *** The variable file-name-coding-system specifies the coding system
5160 to use for encoding file names before operating on them.
5161 It is also used for decoding file names obtained from the system.
5162
5163 *** The command C-\ (toggle-input-method) activates or deactivates
5164 an input method. If no input method has been selected before, the
5165 command prompts for you to specify the language and input method you
5166 want to use.
5167
5168 C-u C-\ (select-input-method) lets you switch to a different input
5169 method. C-h C-\ (or C-h I) describes the current input method.
5170
5171 *** Some input methods remap the keyboard to emulate various keyboard
5172 layouts commonly used for particular scripts. How to do this
5173 remapping properly depends on your actual keyboard layout. To specify
5174 which layout your keyboard has, use M-x quail-set-keyboard-layout.
5175
5176 *** The command C-h C (describe-coding-system) displays
5177 the coding systems currently selected for various purposes, plus
5178 related information.
5179
5180 *** The command C-h h (view-hello-file) displays a file called
5181 HELLO, which has examples of text in many languages, using various
5182 scripts.
5183
5184 *** The command C-h L (describe-language-support) displays
5185 information about the support for a particular language.
5186 You specify the language as an argument.
5187
5188 *** The mode line now contains a letter or character that identifies
5189 the coding system used in the visited file. It normally follows the
5190 first dash.
5191
5192 A dash indicates the default state of affairs: no code conversion
5193 (except CRLF => newline if appropriate). `=' means no conversion
5194 whatsoever. The ISO 8859 coding systems are represented by digits
5195 1 through 9. Other coding systems are represented by letters:
5196
5197 A alternativnyj (Russian)
5198 B big5 (Chinese)
5199 C cn-gb-2312 (Chinese)
5200 C iso-2022-cn (Chinese)
5201 D in-is13194-devanagari (Indian languages)
5202 E euc-japan (Japanese)
5203 I iso-2022-cjk or iso-2022-ss2 (Chinese, Japanese, Korean)
5204 J junet (iso-2022-7) or old-jis (iso-2022-jp-1978-irv) (Japanese)
5205 K euc-korea (Korean)
5206 R koi8 (Russian)
5207 Q tibetan
5208 S shift_jis (Japanese)
5209 T lao
5210 T tis620 (Thai)
5211 V viscii or vscii (Vietnamese)
5212 i iso-2022-lock (Chinese, Japanese, Korean)
5213 k iso-2022-kr (Korean)
5214 v viqr (Vietnamese)
5215 z hz (Chinese)
5216
5217 When you are using a character-only terminal (not a window system),
5218 two additional characters appear in between the dash and the file
5219 coding system. These two characters describe the coding system for
5220 keyboard input, and the coding system for terminal output.
5221
5222 *** The new variable rmail-file-coding-system specifies the code
5223 conversion to use for RMAIL files. The default value is nil.
5224
5225 When you read mail with Rmail, each message is decoded automatically
5226 into Emacs' internal format. This has nothing to do with
5227 rmail-file-coding-system. That variable controls reading and writing
5228 Rmail files themselves.
5229
5230 *** The new variable sendmail-coding-system specifies the code
5231 conversion for outgoing mail. The default value is nil.
5232
5233 Actually, there are three different ways of specifying the coding system
5234 for sending mail:
5235
5236 - If you use C-x RET f in the mail buffer, that takes priority.
5237 - Otherwise, if you set sendmail-coding-system non-nil, that specifies it.
5238 - Otherwise, the default coding system for new files is used,
5239 if that is non-nil. That comes from your language environment.
5240 - Otherwise, Latin-1 is used.
5241
5242 *** The command C-h t (help-with-tutorial) accepts a prefix argument
5243 to specify the language for the tutorial file. Currently, English,
5244 Japanese, Korean and Thai are supported. We welcome additional
5245 translations.
5246
5247 ** An easy new way to visit a file with no code or format conversion
5248 of any kind: Use M-x find-file-literally. There is also a command
5249 insert-file-literally which inserts a file into the current buffer
5250 without any conversion.
5251
5252 ** C-q's handling of octal character codes is changed.
5253 You can now specify any number of octal digits.
5254 RET terminates the digits and is discarded;
5255 any other non-digit terminates the digits and is then used as input.
5256
5257 ** There are new commands for looking up Info documentation for
5258 functions, variables and file names used in your programs.
5259
5260 Type M-x info-lookup-symbol to look up a symbol in the buffer at point.
5261 Type M-x info-lookup-file to look up a file in the buffer at point.
5262
5263 Precisely which Info files are used to look it up depends on the major
5264 mode. For example, in C mode, the GNU libc manual is used.
5265
5266 ** M-TAB in most programming language modes now runs the command
5267 complete-symbol. This command performs completion on the symbol name
5268 in the buffer before point.
5269
5270 With a numeric argument, it performs completion based on the set of
5271 symbols documented in the Info files for the programming language that
5272 you are using.
5273
5274 With no argument, it does completion based on the current tags tables,
5275 just like the old binding of M-TAB (complete-tag).
5276
5277 ** File locking works with NFS now.
5278
5279 The lock file for FILENAME is now a symbolic link named .#FILENAME,
5280 in the same directory as FILENAME.
5281
5282 This means that collision detection between two different machines now
5283 works reasonably well; it also means that no file server or directory
5284 can become a bottleneck.
5285
5286 The new method does have drawbacks. It means that collision detection
5287 does not operate when you edit a file in a directory where you cannot
5288 create new files. Collision detection also doesn't operate when the
5289 file server does not support symbolic links. But these conditions are
5290 rare, and the ability to have collision detection while using NFS is
5291 so useful that the change is worth while.
5292
5293 When Emacs or a system crashes, this may leave behind lock files which
5294 are stale. So you may occasionally get warnings about spurious
5295 collisions. When you determine that the collision is spurious, just
5296 tell Emacs to go ahead anyway.
5297
5298 ** If you wish to use Show Paren mode to display matching parentheses,
5299 it is no longer sufficient to load paren.el. Instead you must call
5300 show-paren-mode.
5301
5302 ** If you wish to use Delete Selection mode to replace a highlighted
5303 selection when you insert new text, it is no longer sufficient to load
5304 delsel.el. Instead you must call the function delete-selection-mode.
5305
5306 ** If you wish to use Partial Completion mode to complete partial words
5307 within symbols or filenames, it is no longer sufficient to load
5308 complete.el. Instead you must call the function partial-completion-mode.
5309
5310 ** If you wish to use uniquify to rename buffers for you,
5311 it is no longer sufficient to load uniquify.el. You must also
5312 set uniquify-buffer-name-style to one of the non-nil legitimate values.
5313
5314 ** Changes in View mode.
5315
5316 *** Several new commands are available in View mode.
5317 Do H in view mode for a list of commands.
5318
5319 *** There are two new commands for entering View mode:
5320 view-file-other-frame and view-buffer-other-frame.
5321
5322 *** Exiting View mode does a better job of restoring windows to their
5323 previous state.
5324
5325 *** New customization variable view-scroll-auto-exit. If non-nil,
5326 scrolling past end of buffer makes view mode exit.
5327
5328 *** New customization variable view-exits-all-viewing-windows. If
5329 non-nil, view-mode will at exit restore all windows viewing buffer,
5330 not just the selected window.
5331
5332 *** New customization variable view-read-only. If non-nil, visiting a
5333 read-only file automatically enters View mode, and toggle-read-only
5334 turns View mode on or off.
5335
5336 *** New customization variable view-remove-frame-by-deleting controls
5337 how to remove a not needed frame at view mode exit. If non-nil,
5338 delete the frame, if nil make an icon of it.
5339
5340 ** C-x v l, the command to print a file's version control log,
5341 now positions point at the entry for the file's current branch version.
5342
5343 ** C-x v =, the command to compare a file with the last checked-in version,
5344 has a new feature. If the file is currently not locked, so that it is
5345 presumably identical to the last checked-in version, the command now asks
5346 which version to compare with.
5347
5348 ** When using hideshow.el, incremental search can temporarily show hidden
5349 blocks if a match is inside the block.
5350
5351 The block is hidden again if the search is continued and the next match
5352 is outside the block. By customizing the variable
5353 isearch-hide-immediately you can choose to hide all the temporarily
5354 shown blocks only when exiting from incremental search.
5355
5356 By customizing the variable hs-isearch-open you can choose what kind
5357 of blocks to temporarily show during isearch: comment blocks, code
5358 blocks, all of them or none.
5359
5360 ** The new command C-x 4 0 (kill-buffer-and-window) kills the
5361 current buffer and deletes the selected window. It asks for
5362 confirmation first.
5363
5364 ** C-x C-w, which saves the buffer into a specified file name,
5365 now changes the major mode according to that file name.
5366 However, the mode will not be changed if
5367 (1) a local variables list or the `-*-' line specifies a major mode, or
5368 (2) the current major mode is a "special" mode,
5369 not suitable for ordinary files, or
5370 (3) the new file name does not particularly specify any mode.
5371
5372 This applies to M-x set-visited-file-name as well.
5373
5374 However, if you set change-major-mode-with-file-name to nil, then
5375 these commands do not change the major mode.
5376
5377 ** M-x occur changes.
5378
5379 *** If the argument to M-x occur contains upper case letters,
5380 it performs a case-sensitive search.
5381
5382 *** In the *Occur* buffer made by M-x occur,
5383 if you type g or M-x revert-buffer, this repeats the search
5384 using the same regular expression and the same buffer as before.
5385
5386 ** In Transient Mark mode, the region in any one buffer is highlighted
5387 in just one window at a time. At first, it is highlighted in the
5388 window where you set the mark. The buffer's highlighting remains in
5389 that window unless you select to another window which shows the same
5390 buffer--then the highlighting moves to that window.
5391
5392 ** The feature to suggest key bindings when you use M-x now operates
5393 after the command finishes. The message suggesting key bindings
5394 appears temporarily in the echo area. The previous echo area contents
5395 come back after a few seconds, in case they contain useful information.
5396
5397 ** Each frame now independently records the order for recently
5398 selected buffers, so that the default for C-x b is now based on the
5399 buffers recently selected in the selected frame.
5400
5401 ** Outline mode changes.
5402
5403 *** Outline mode now uses overlays (this is the former noutline.el).
5404
5405 *** Incremental searches skip over invisible text in Outline mode.
5406
5407 ** When a minibuffer window is active but not the selected window, if
5408 you try to use the minibuffer, you used to get a nested minibuffer.
5409 Now, this not only gives an error, it also cancels the minibuffer that
5410 was already active.
5411
5412 The motive for this change is so that beginning users do not
5413 unknowingly move away from minibuffers, leaving them active, and then
5414 get confused by it.
5415
5416 If you want to be able to have recursive minibuffers, you must
5417 set enable-recursive-minibuffers to non-nil.
5418
5419 ** Changes in dynamic abbrevs.
5420
5421 *** Expanding dynamic abbrevs with M-/ is now smarter about case
5422 conversion. If the expansion has mixed case not counting the first
5423 character, and the abbreviation matches the beginning of the expansion
5424 including case, then the expansion is copied verbatim.
5425
5426 The expansion is also copied verbatim if the abbreviation itself has
5427 mixed case. And using SPC M-/ to copy an additional word always
5428 copies it verbatim except when the previous copied word is all caps.
5429
5430 *** The values of `dabbrev-case-replace' and `dabbrev-case-fold-search'
5431 are no longer Lisp expressions. They have simply three possible
5432 values.
5433
5434 `dabbrev-case-replace' has these three values: nil (don't preserve
5435 case), t (do), or `case-replace' (do like M-x query-replace).
5436 `dabbrev-case-fold-search' has these three values: nil (don't ignore
5437 case), t (do), or `case-fold-search' (do like search).
5438
5439 ** Minibuffer history lists are truncated automatically now to a
5440 certain length. The variable history-length specifies how long they
5441 can be. The default value is 30.
5442
5443 ** Changes in Mail mode.
5444
5445 *** The key C-x m no longer runs the `mail' command directly.
5446 Instead, it runs the command `compose-mail', which invokes the mail
5447 composition mechanism you have selected with the variable
5448 `mail-user-agent'. The default choice of user agent is
5449 `sendmail-user-agent', which gives behavior compatible with the old
5450 behavior.
5451
5452 C-x 4 m now runs compose-mail-other-window, and C-x 5 m runs
5453 compose-mail-other-frame.
5454
5455 *** While composing a reply to a mail message, from Rmail, you can use
5456 the command C-c C-r to cite just the region from the message you are
5457 replying to. This copies the text which is the selected region in the
5458 buffer that shows the original message.
5459
5460 *** The command C-c C-i inserts a file at the end of the message,
5461 with separator lines around the contents.
5462
5463 *** The command M-x expand-mail-aliases expands all mail aliases
5464 in suitable mail headers. Emacs automatically extracts mail alias
5465 definitions from your mail alias file (e.g., ~/.mailrc). You do not
5466 need to expand mail aliases yourself before sending mail.
5467
5468 *** New features in the mail-complete command.
5469
5470 **** The mail-complete command now inserts the user's full name,
5471 for local users or if that is known. The variable mail-complete-style
5472 controls the style to use, and whether to do this at all.
5473 Its values are like those of mail-from-style.
5474
5475 **** The variable mail-passwd-command lets you specify a shell command
5476 to run to fetch a set of password-entries that add to the ones in
5477 /etc/passwd.
5478
5479 **** The variable mail-passwd-file now specifies a list of files to read
5480 to get the list of user ids. By default, one file is used:
5481 /etc/passwd.
5482
5483 ** You can "quote" a file name to inhibit special significance of
5484 special syntax, by adding `/:' to the beginning. Thus, if you have a
5485 directory named `/foo:', you can prevent it from being treated as a
5486 reference to a remote host named `foo' by writing it as `/:/foo:'.
5487
5488 Emacs uses this new construct automatically when necessary, such as
5489 when you start it with a working directory whose name might otherwise
5490 be taken to be magic.
5491
5492 ** There is a new command M-x grep-find which uses find to select
5493 files to search through, and grep to scan them. The output is
5494 available in a Compile mode buffer, as with M-x grep.
5495
5496 M-x grep now uses the -e option if the grep program supports that.
5497 (-e prevents problems if the search pattern starts with a dash.)
5498
5499 ** In Dired, the & command now flags for deletion the files whose names
5500 suggest they are probably not needed in the long run.
5501
5502 In Dired, * is now a prefix key for mark-related commands.
5503
5504 new key dired.el binding old key
5505 ------- ---------------- -------
5506 * c dired-change-marks c
5507 * m dired-mark m
5508 * * dired-mark-executables * (binding deleted)
5509 * / dired-mark-directories / (binding deleted)
5510 * @ dired-mark-symlinks @ (binding deleted)
5511 * u dired-unmark u
5512 * DEL dired-unmark-backward DEL
5513 * ? dired-unmark-all-files M-C-?
5514 * ! dired-unmark-all-marks
5515 * % dired-mark-files-regexp % m
5516 * C-n dired-next-marked-file M-}
5517 * C-p dired-prev-marked-file M-{
5518
5519 ** Rmail changes.
5520
5521 *** When Rmail cannot convert your incoming mail into Babyl format, it
5522 saves the new mail in the file RMAILOSE.n, where n is an integer
5523 chosen to make a unique name. This way, Rmail will not keep crashing
5524 each time you run it.
5525
5526 *** In Rmail, the variable rmail-summary-line-count-flag now controls
5527 whether to include the line count in the summary. Non-nil means yes.
5528
5529 *** In Rmail summary buffers, d and C-d (the commands to delete
5530 messages) now take repeat counts as arguments. A negative argument
5531 means to move in the opposite direction.
5532
5533 *** In Rmail, the t command now takes an optional argument which lets
5534 you specify whether to show the message headers in full or pruned.
5535
5536 *** In Rmail, the new command w (rmail-output-body-to-file) writes
5537 just the body of the current message into a file, without the headers.
5538 It takes the file name from the message subject, by default, but you
5539 can edit that file name in the minibuffer before it is actually used
5540 for output.
5541
5542 ** Gnus changes.
5543
5544 *** nntp.el has been totally rewritten in an asynchronous fashion.
5545
5546 *** Article prefetching functionality has been moved up into
5547 Gnus.
5548
5549 *** Scoring can now be performed with logical operators like
5550 `and', `or', `not', and parent redirection.
5551
5552 *** Article washing status can be displayed in the
5553 article mode line.
5554
5555 *** gnus.el has been split into many smaller files.
5556
5557 *** Suppression of duplicate articles based on Message-ID.
5558
5559 (setq gnus-suppress-duplicates t)
5560
5561 *** New variables for specifying what score and adapt files
5562 are to be considered home score and adapt files. See
5563 `gnus-home-score-file' and `gnus-home-adapt-files'.
5564
5565 *** Groups can inherit group parameters from parent topics.
5566
5567 *** Article editing has been revamped and is now usable.
5568
5569 *** Signatures can be recognized in more intelligent fashions.
5570 See `gnus-signature-separator' and `gnus-signature-limit'.
5571
5572 *** Summary pick mode has been made to look more nn-like.
5573 Line numbers are displayed and the `.' command can be
5574 used to pick articles.
5575
5576 *** Commands for moving the .newsrc.eld from one server to
5577 another have been added.
5578
5579 `M-x gnus-change-server'
5580
5581 *** A way to specify that "uninteresting" fields be suppressed when
5582 generating lines in buffers.
5583
5584 *** Several commands in the group buffer can be undone with
5585 `M-C-_'.
5586
5587 *** Scoring can be done on words using the new score type `w'.
5588
5589 *** Adaptive scoring can be done on a Subject word-by-word basis:
5590
5591 (setq gnus-use-adaptive-scoring '(word))
5592
5593 *** Scores can be decayed.
5594
5595 (setq gnus-decay-scores t)
5596
5597 *** Scoring can be performed using a regexp on the Date header. The
5598 Date is normalized to compact ISO 8601 format first.
5599
5600 *** A new command has been added to remove all data on articles from
5601 the native server.
5602
5603 `M-x gnus-group-clear-data-on-native-groups'
5604
5605 *** A new command for reading collections of documents
5606 (nndoc with nnvirtual on top) has been added -- `M-C-d'.
5607
5608 *** Process mark sets can be pushed and popped.
5609
5610 *** A new mail-to-news backend makes it possible to post
5611 even when the NNTP server doesn't allow posting.
5612
5613 *** A new backend for reading searches from Web search engines
5614 (DejaNews, Alta Vista, InReference) has been added.
5615
5616 Use the `G w' command in the group buffer to create such
5617 a group.
5618
5619 *** Groups inside topics can now be sorted using the standard
5620 sorting functions, and each topic can be sorted independently.
5621
5622 See the commands under the `T S' submap.
5623
5624 *** Subsets of the groups can be sorted independently.
5625
5626 See the commands under the `G P' submap.
5627
5628 *** Cached articles can be pulled into the groups.
5629
5630 Use the `Y c' command.
5631
5632 *** Score files are now applied in a more reliable order.
5633
5634 *** Reports on where mail messages end up can be generated.
5635
5636 `M-x nnmail-split-history'
5637
5638 *** More hooks and functions have been added to remove junk
5639 from incoming mail before saving the mail.
5640
5641 See `nnmail-prepare-incoming-header-hook'.
5642
5643 *** The nnml mail backend now understands compressed article files.
5644
5645 *** To enable Gnus to read/post multi-lingual articles, you must execute
5646 the following code, for instance, in your .emacs.
5647
5648 (add-hook 'gnus-startup-hook 'gnus-mule-initialize)
5649
5650 Then, when you start Gnus, it will decode non-ASCII text automatically
5651 and show appropriate characters. (Note: if you are using gnus-mime
5652 from the SEMI package, formerly known as TM, you should NOT add this
5653 hook to gnus-startup-hook; gnus-mime has its own method of handling
5654 this issue.)
5655
5656 Since it is impossible to distinguish all coding systems
5657 automatically, you may need to specify a choice of coding system for a
5658 particular news group. This can be done by:
5659
5660 (gnus-mule-add-group NEWSGROUP 'CODING-SYSTEM)
5661
5662 Here NEWSGROUP should be a string which names a newsgroup or a tree
5663 of newsgroups. If NEWSGROUP is "XXX.YYY", all news groups under
5664 "XXX.YYY" (including "XXX.YYY.ZZZ") will use the specified coding
5665 system. CODING-SYSTEM specifies which coding system to use (for both
5666 for reading and posting).
5667
5668 CODING-SYSTEM can also be a cons cell of the form
5669 (READ-CODING-SYSTEM . POST-CODING-SYSTEM)
5670 Then READ-CODING-SYSTEM is used when you read messages from the
5671 newsgroups, while POST-CODING-SYSTEM is used when you post messages
5672 there.
5673
5674 Emacs knows the right coding systems for certain newsgroups by
5675 default. Here are some of these default settings:
5676
5677 (gnus-mule-add-group "fj" 'iso-2022-7)
5678 (gnus-mule-add-group "alt.chinese.text" 'hz-gb-2312)
5679 (gnus-mule-add-group "alt.hk" 'hz-gb-2312)
5680 (gnus-mule-add-group "alt.chinese.text.big5" 'cn-big5)
5681 (gnus-mule-add-group "soc.culture.vietnamese" '(nil . viqr))
5682
5683 When you reply by mail to an article, these settings are ignored;
5684 the mail is encoded according to sendmail-coding-system, as usual.
5685
5686 ** CC mode changes.
5687
5688 *** If you edit primarily one style of C (or C++, Objective-C, Java)
5689 code, you may want to make the CC Mode style variables have global
5690 values so that you can set them directly in your .emacs file. To do
5691 this, set c-style-variables-are-local-p to nil in your .emacs file.
5692 Note that this only takes effect if you do it *before* cc-mode.el is
5693 loaded.
5694
5695 If you typically edit more than one style of C (or C++, Objective-C,
5696 Java) code in a single Emacs session, you may want to make the CC Mode
5697 style variables have buffer local values. By default, all buffers
5698 share the same style variable settings; to make them buffer local, set
5699 c-style-variables-are-local-p to t in your .emacs file. Note that you
5700 must do this *before* CC Mode is loaded.
5701
5702 *** The new variable c-indentation-style holds the C style name
5703 of the current buffer.
5704
5705 *** The variable c-block-comments-indent-p has been deleted, because
5706 it is no longer necessary. C mode now handles all the supported styles
5707 of block comments, with no need to say which one you will use.
5708
5709 *** There is a new indentation style "python", which specifies the C
5710 style that the Python developers like.
5711
5712 *** There is a new c-cleanup-list option: brace-elseif-brace.
5713 This says to put ...} else if (...) {... on one line,
5714 just as brace-else-brace says to put ...} else {... on one line.
5715
5716 ** VC Changes [new]
5717
5718 ** In vc-retrieve-snapshot (C-x v r), if you don't specify a snapshot
5719 name, it retrieves the *latest* versions of all files in the current
5720 directory and its subdirectories (aside from files already locked).
5721
5722 This feature is useful if your RCS directory is a link to a common
5723 master directory, and you want to pick up changes made by other
5724 developers.
5725
5726 You can do the same thing for an individual file by typing C-u C-x C-q
5727 RET in a buffer visiting that file.
5728
5729 *** VC can now handle files under CVS that are being "watched" by
5730 other developers. Such files are made read-only by CVS. To get a
5731 writable copy, type C-x C-q in a buffer visiting such a file. VC then
5732 calls "cvs edit", which notifies the other developers of it.
5733
5734 *** vc-version-diff (C-u C-x v =) now suggests reasonable defaults for
5735 version numbers, based on the current state of the file.
5736
5737 ** Calendar changes.
5738
5739 A new function, list-holidays, allows you list holidays or subclasses
5740 of holidays for ranges of years. Related menu items allow you do this
5741 for the year of the selected date, or the following/previous years.
5742
5743 ** ps-print changes
5744
5745 There are some new user variables for customizing the page layout.
5746
5747 *** Paper size, paper orientation, columns
5748
5749 The variable `ps-paper-type' determines the size of paper ps-print
5750 formats for; it should contain one of the symbols:
5751 `a4' `a3' `letter' `legal' `letter-small' `tabloid'
5752 `ledger' `statement' `executive' `a4small' `b4' `b5'
5753 It defaults to `letter'.
5754 If you need other sizes, see the variable `ps-page-dimensions-database'.
5755
5756 The variable `ps-landscape-mode' determines the orientation
5757 of the printing on the page. nil, the default, means "portrait" mode,
5758 non-nil means "landscape" mode.
5759
5760 The variable `ps-number-of-columns' must be a positive integer.
5761 It determines the number of columns both in landscape and portrait mode.
5762 It defaults to 1.
5763
5764 *** Horizontal layout
5765
5766 The horizontal layout is determined by the variables
5767 `ps-left-margin', `ps-inter-column', and `ps-right-margin'.
5768 All are measured in points.
5769
5770 *** Vertical layout
5771
5772 The vertical layout is determined by the variables
5773 `ps-bottom-margin', `ps-top-margin', and `ps-header-offset'.
5774 All are measured in points.
5775
5776 *** Headers
5777
5778 If the variable `ps-print-header' is nil, no header is printed. Then
5779 `ps-header-offset' is not relevant and `ps-top-margin' represents the
5780 margin above the text.
5781
5782 If the variable `ps-print-header-frame' is non-nil, a gaudy
5783 framing box is printed around the header.
5784
5785 The contents of the header are determined by `ps-header-lines',
5786 `ps-show-n-of-n', `ps-left-header' and `ps-right-header'.
5787
5788 The height of the header is determined by `ps-header-line-pad',
5789 `ps-header-font-family', `ps-header-title-font-size' and
5790 `ps-header-font-size'.
5791
5792 *** Font managing
5793
5794 The variable `ps-font-family' determines which font family is to be
5795 used for ordinary text. Its value must be a key symbol in the alist
5796 `ps-font-info-database'. You can add other font families by adding
5797 elements to this alist.
5798
5799 The variable `ps-font-size' determines the size of the font
5800 for ordinary text. It defaults to 8.5 points.
5801
5802 ** hideshow changes.
5803
5804 *** now supports hiding of blocks of single line comments (like // for
5805 C++, ; for lisp).
5806
5807 *** Support for java-mode added.
5808
5809 *** When doing `hs-hide-all' it is now possible to also hide the comments
5810 in the file if `hs-hide-comments-when-hiding-all' is set.
5811
5812 *** The new function `hs-hide-initial-comment' hides the the comments at
5813 the beginning of the files. Finally those huge RCS logs don't stay in your
5814 way! This is run by default when entering the `hs-minor-mode'.
5815
5816 *** Now uses overlays instead of `selective-display', so is more
5817 robust and a lot faster.
5818
5819 *** A block beginning can span multiple lines.
5820
5821 *** The new variable `hs-show-hidden-short-form' if t, directs hideshow
5822 to show only the beginning of a block when it is hidden. See the
5823 documentation for more details.
5824
5825 ** Changes in Enriched mode.
5826
5827 *** When you visit a file in enriched-mode, Emacs will make sure it is
5828 filled to the current fill-column. This behavior is now independent
5829 of the size of the window. When you save the file, the fill-column in
5830 use is stored as well, so that the whole buffer need not be refilled
5831 the next time unless the fill-column is different.
5832
5833 *** use-hard-newlines is now a minor mode. When it is enabled, Emacs
5834 distinguishes between hard and soft newlines, and treats hard newlines
5835 as paragraph boundaries. Otherwise all newlines inserted are marked
5836 as soft, and paragraph boundaries are determined solely from the text.
5837
5838 ** Font Lock mode
5839
5840 *** Custom support
5841
5842 The variables font-lock-face-attributes, font-lock-display-type and
5843 font-lock-background-mode are now obsolete; the recommended way to specify the
5844 faces to use for Font Lock mode is with M-x customize-group on the new custom
5845 group font-lock-highlighting-faces. If you set font-lock-face-attributes in
5846 your ~/.emacs file, Font Lock mode will respect its value. However, you should
5847 consider converting from setting that variable to using M-x customize.
5848
5849 You can still use X resources to specify Font Lock face appearances.
5850
5851 *** Maximum decoration
5852
5853 Fontification now uses the maximum level of decoration supported by
5854 default. Previously, fontification used a mode-specific default level
5855 of decoration, which is typically the minimum level of decoration
5856 supported. You can set font-lock-maximum-decoration to nil
5857 to get the old behavior.
5858
5859 *** New support
5860
5861 Support is now provided for Java, Objective-C, AWK and SIMULA modes.
5862
5863 Note that Font Lock mode can be turned on without knowing exactly what modes
5864 support Font Lock mode, via the command global-font-lock-mode.
5865
5866 *** Configurable support
5867
5868 Support for C, C++, Objective-C and Java can be more easily configured for
5869 additional types and classes via the new variables c-font-lock-extra-types,
5870 c++-font-lock-extra-types, objc-font-lock-extra-types and, you guessed it,
5871 java-font-lock-extra-types. These value of each of these variables should be a
5872 list of regexps matching the extra type names. For example, the default value
5873 of c-font-lock-extra-types is ("\\sw+_t") which means fontification follows the
5874 convention that C type names end in _t. This results in slower fontification.
5875
5876 Of course, you can change the variables that specify fontification in whatever
5877 way you wish, typically by adding regexps. However, these new variables make
5878 it easier to make specific and common changes for the fontification of types.
5879
5880 *** Adding highlighting patterns to existing support
5881
5882 You can use the new function font-lock-add-keywords to add your own
5883 highlighting patterns, such as for project-local or user-specific constructs,
5884 for any mode.
5885
5886 For example, to highlight `FIXME:' words in C comments, put:
5887
5888 (font-lock-add-keywords 'c-mode '(("\\<FIXME:" 0 font-lock-warning-face t)))
5889
5890 in your ~/.emacs.
5891
5892 *** New faces
5893
5894 Font Lock now defines two new faces, font-lock-builtin-face and
5895 font-lock-warning-face. These are intended to highlight builtin keywords,
5896 distinct from a language's normal keywords, and objects that should be brought
5897 to user attention, respectively. Various modes now use these new faces.
5898
5899 *** Changes to fast-lock support mode
5900
5901 The fast-lock package, one of the two Font Lock support modes, can now process
5902 cache files silently. You can use the new variable fast-lock-verbose, in the
5903 same way as font-lock-verbose, to control this feature.
5904
5905 *** Changes to lazy-lock support mode
5906
5907 The lazy-lock package, one of the two Font Lock support modes, can now fontify
5908 according to the true syntactic context relative to other lines. You can use
5909 the new variable lazy-lock-defer-contextually to control this feature. If
5910 non-nil, changes to the buffer will cause subsequent lines in the buffer to be
5911 refontified after lazy-lock-defer-time seconds of idle time. If nil, then only
5912 the modified lines will be refontified; this is the same as the previous Lazy
5913 Lock mode behaviour and the behaviour of Font Lock mode.
5914
5915 This feature is useful in modes where strings or comments can span lines.
5916 For example, if a string or comment terminating character is deleted, then if
5917 this feature is enabled subsequent lines in the buffer will be correctly
5918 refontified to reflect their new syntactic context. Previously, only the line
5919 containing the deleted character would be refontified and you would have to use
5920 the command M-g M-g (font-lock-fontify-block) to refontify some lines.
5921
5922 As a consequence of this new feature, two other variables have changed:
5923
5924 Variable `lazy-lock-defer-driven' is renamed `lazy-lock-defer-on-scrolling'.
5925 Variable `lazy-lock-defer-time' can now only be a time, i.e., a number.
5926 Buffer modes for which on-the-fly deferral applies can be specified via the
5927 new variable `lazy-lock-defer-on-the-fly'.
5928
5929 If you set these variables in your ~/.emacs, then you may have to change those
5930 settings.
5931
5932 ** Ada mode changes.
5933
5934 *** There is now better support for using find-file.el with Ada mode.
5935 If you switch between spec and body, the cursor stays in the same
5936 procedure (modulo overloading). If a spec has no body file yet, but
5937 you try to switch to its body file, Ada mode now generates procedure
5938 stubs.
5939
5940 *** There are two new commands:
5941 - `ada-make-local' : invokes gnatmake on the current buffer
5942 - `ada-check-syntax' : check syntax of current buffer.
5943
5944 The user options `ada-compiler-make', `ada-make-options',
5945 `ada-language-version', `ada-compiler-syntax-check', and
5946 `ada-compile-options' are used within these commands.
5947
5948 *** Ada mode can now work with Outline minor mode. The outline level
5949 is calculated from the indenting, not from syntactic constructs.
5950 Outlining does not work if your code is not correctly indented.
5951
5952 *** The new function `ada-gnat-style' converts the buffer to the style of
5953 formatting used in GNAT. It places two blanks after a comment start,
5954 places one blank between a word end and an opening '(', and puts one
5955 space between a comma and the beginning of a word.
5956
5957 ** Scheme mode changes.
5958
5959 *** Scheme mode indentation now uses many of the facilities of Lisp
5960 mode; therefore, the variables to customize it are the variables used
5961 for Lisp mode which have names starting with `lisp-'. The variables
5962 with names starting with `scheme-' which used to do this no longer
5963 have any effect.
5964
5965 If you want to use different indentation for Scheme and Lisp, this is
5966 still possible, but now you must do it by adding a hook to
5967 scheme-mode-hook, which could work by setting the `lisp-' indentation
5968 variables as buffer-local variables.
5969
5970 *** DSSSL mode is a variant of Scheme mode, for editing DSSSL scripts.
5971 Use M-x dsssl-mode.
5972
5973 ** Changes to the emacsclient program
5974
5975 *** If a socket can't be found, and environment variables LOGNAME or
5976 USER are set, emacsclient now looks for a socket based on the UID
5977 associated with the name. That is an emacsclient running as root
5978 can connect to an Emacs server started by a non-root user.
5979
5980 *** The emacsclient program now accepts an option --no-wait which tells
5981 it to return immediately without waiting for you to "finish" the
5982 buffer in Emacs.
5983
5984 *** The new option --alternate-editor allows to specify an editor to
5985 use if Emacs is not running. The environment variable
5986 ALTERNATE_EDITOR can be used for the same effect; the command line
5987 option takes precedence.
5988
5989 ** M-x eldoc-mode enables a minor mode in which the echo area
5990 constantly shows the parameter list for function being called at point
5991 (in Emacs Lisp and Lisp Interaction modes only).
5992
5993 ** C-x n d now runs the new command narrow-to-defun,
5994 which narrows the accessible parts of the buffer to just
5995 the current defun.
5996
5997 ** Emacs now handles the `--' argument in the standard way; all
5998 following arguments are treated as ordinary file names.
5999
6000 ** On MSDOS and Windows, the bookmark file is now called _emacs.bmk,
6001 and the saved desktop file is now called _emacs.desktop (truncated if
6002 necessary).
6003
6004 ** When you kill a buffer that visits a file,
6005 if there are any registers that save positions in the file,
6006 these register values no longer become completely useless.
6007 If you try to go to such a register with C-x j, then you are
6008 asked whether to visit the file again. If you say yes,
6009 it visits the file and then goes to the same position.
6010
6011 ** When you visit a file that changes frequently outside Emacs--for
6012 example, a log of output from a process that continues to run--it may
6013 be useful for Emacs to revert the file without querying you whenever
6014 you visit the file afresh with C-x C-f.
6015
6016 You can request this behavior for certain files by setting the
6017 variable revert-without-query to a list of regular expressions. If a
6018 file's name matches any of these regular expressions, find-file and
6019 revert-buffer revert the buffer without asking for permission--but
6020 only if you have not edited the buffer text yourself.
6021
6022 ** set-default-font has been renamed to set-frame-font
6023 since it applies only to the current frame.
6024
6025 ** In TeX mode, you can use the variable tex-main-file to specify the
6026 file for tex-file to run TeX on. (By default, tex-main-file is nil,
6027 and tex-file runs TeX on the current visited file.)
6028
6029 This is useful when you are editing a document that consists of
6030 multiple files. In each of the included files, you can set up a local
6031 variable list which specifies the top-level file of your document for
6032 tex-main-file. Then tex-file will run TeX on the whole document
6033 instead of just the file you are editing.
6034
6035 ** RefTeX mode
6036
6037 RefTeX mode is a new minor mode with special support for \label, \ref
6038 and \cite macros in LaTeX documents. RefTeX distinguishes labels of
6039 different environments (equation, figure, ...) and has full support for
6040 multifile documents. To use it, select a buffer with a LaTeX document and
6041 turn the mode on with M-x reftex-mode. Here are the main user commands:
6042
6043 C-c ( reftex-label
6044 Creates a label semi-automatically. RefTeX is context sensitive and
6045 knows which kind of label is needed.
6046
6047 C-c ) reftex-reference
6048 Offers in a menu all labels in the document, along with context of the
6049 label definition. The selected label is referenced as \ref{LABEL}.
6050
6051 C-c [ reftex-citation
6052 Prompts for a regular expression and displays a list of matching BibTeX
6053 database entries. The selected entry is cited with a \cite{KEY} macro.
6054
6055 C-c & reftex-view-crossref
6056 Views the cross reference of a \ref or \cite command near point.
6057
6058 C-c = reftex-toc
6059 Shows a table of contents of the (multifile) document. From there you
6060 can quickly jump to every section.
6061
6062 Under X, RefTeX installs a "Ref" menu in the menu bar, with additional
6063 commands. Press `?' to get help when a prompt mentions this feature.
6064 Full documentation and customization examples are in the file
6065 reftex.el. You can use the finder to view the file documentation:
6066 C-h p --> tex --> reftex.el
6067
6068 ** Changes in BibTeX mode.
6069
6070 *** Info documentation is now available.
6071
6072 *** Don't allow parentheses in string constants anymore. This confused
6073 both the BibTeX program and Emacs BibTeX mode.
6074
6075 *** Renamed variable bibtex-mode-user-optional-fields to
6076 bibtex-user-optional-fields.
6077
6078 *** Removed variable bibtex-include-OPTannote
6079 (use bibtex-user-optional-fields instead).
6080
6081 *** New interactive functions to copy and kill fields and complete
6082 entries to the BibTeX kill ring, from where they can be yanked back by
6083 appropriate functions.
6084
6085 *** New interactive functions for repositioning and marking of
6086 entries. They are bound by default to M-C-l and M-C-h.
6087
6088 *** New hook bibtex-clean-entry-hook. It is called after entry has
6089 been cleaned.
6090
6091 *** New variable bibtex-field-delimiters, which replaces variables
6092 bibtex-field-{left|right}-delimiter.
6093
6094 *** New variable bibtex-entry-delimiters to determine how entries
6095 shall be delimited.
6096
6097 *** Allow preinitialization of fields. See documentation of
6098 bibtex-user-optional-fields, bibtex-entry-field-alist, and
6099 bibtex-include-OPTkey for details.
6100
6101 *** Book and InBook entries require either an author or an editor
6102 field. This is now supported by bibtex.el. Alternative fields are
6103 prefixed with `ALT'.
6104
6105 *** New variable bibtex-entry-format, which replaces variable
6106 bibtex-clean-entry-zap-empty-opts and allows specification of many
6107 formatting options performed on cleaning an entry (see variable
6108 documentation).
6109
6110 *** Even more control on how automatic keys are generated. See
6111 documentation of bibtex-generate-autokey for details. Transcriptions
6112 for foreign languages other than German are now handled, too.
6113
6114 *** New boolean user option bibtex-comma-after-last-field to decide if
6115 comma should be inserted at end of last field.
6116
6117 *** New boolean user option bibtex-align-at-equal-sign to determine if
6118 alignment should be made at left side of field contents or at equal
6119 signs. New user options to control entry layout (e.g. indentation).
6120
6121 *** New function bibtex-fill-entry to realign entries.
6122
6123 *** New function bibtex-reformat to reformat region or buffer.
6124
6125 *** New function bibtex-convert-alien to convert a BibTeX database
6126 from alien sources.
6127
6128 *** New function bibtex-complete-key (similar to bibtex-complete-string)
6129 to complete prefix to a key defined in buffer. Mainly useful in
6130 crossref entries.
6131
6132 *** New function bibtex-count-entries to count entries in buffer or
6133 region.
6134
6135 *** Added support for imenu.
6136
6137 *** The function `bibtex-validate' now checks current region instead
6138 of buffer if mark is active. Now it shows all errors of buffer in a
6139 `compilation mode' buffer. You can use the normal commands (e.g.
6140 `next-error') for compilation modes to jump to errors.
6141
6142 *** New variable `bibtex-string-file-path' to determine where the files
6143 from `bibtex-string-files' are searched.
6144
6145 ** Iso Accents mode now supports Latin-3 as an alternative.
6146
6147 ** The command next-error now opens blocks hidden by hideshow.
6148
6149 ** The function using-unix-filesystems has been replaced by the
6150 functions add-untranslated-filesystem and remove-untranslated-filesystem.
6151 Each of these functions takes the name of a drive letter or directory
6152 as an argument.
6153
6154 When a filesystem is added as untranslated, all files on it are read
6155 and written in binary mode (no cr/lf translation is performed).
6156
6157 ** browse-url changes
6158
6159 *** New methods for: Grail (browse-url-generic), MMM (browse-url-mmm),
6160 Lynx in a separate xterm (browse-url-lynx-xterm) or in an Emacs window
6161 (browse-url-lynx-emacs), remote W3 (browse-url-w3-gnudoit), generic
6162 non-remote-controlled browsers (browse-url-generic) and associated
6163 customization variables.
6164
6165 *** New commands `browse-url-of-region' and `browse-url'.
6166
6167 *** URLs marked up with <URL:...> (RFC1738) work if broken across
6168 lines. Browsing methods can be associated with URL regexps
6169 (e.g. mailto: URLs) via `browse-url-browser-function'.
6170
6171 ** Changes in Ediff
6172
6173 *** Clicking Mouse-2 on a brief command description in Ediff control panel
6174 pops up the Info file for this command.
6175
6176 *** There is now a variable, ediff-autostore-merges, which controls whether
6177 the result of a merge is saved in a file. By default, this is done only when
6178 merge is done from a session group (eg, when merging files in two different
6179 directories).
6180
6181 *** Since Emacs 19.31 (this hasn't been announced before), Ediff can compare
6182 and merge groups of files residing in different directories, or revisions of
6183 files in the same directory.
6184
6185 *** Since Emacs 19.31, Ediff can apply multi-file patches interactively.
6186 The patches must be in the context format or GNU unified format. (The bug
6187 related to the GNU format has now been fixed.)
6188
6189 ** Changes in Viper
6190
6191 *** The startup file is now .viper instead of .vip
6192 *** All variable/function names have been changed to start with viper-
6193 instead of vip-.
6194 *** C-\ now simulates the meta-key in all Viper states.
6195 *** C-z in Insert state now escapes to Vi for the duration of the next
6196 Viper command. In Vi and Insert states, C-z behaves as before.
6197 *** C-c \ escapes to Vi for one command if Viper is in Insert or Emacs states.
6198 *** _ is no longer the meta-key in Vi state.
6199 *** The variable viper-insert-state-cursor-color can be used to change cursor
6200 color when Viper is in insert state.
6201 *** If search lands the cursor near the top or the bottom of the window,
6202 Viper pulls the window up or down to expose more context. The variable
6203 viper-adjust-window-after-search controls this behavior.
6204
6205 ** Etags changes.
6206
6207 *** In C, C++, Objective C and Java, Etags tags global variables by
6208 default. The resulting tags files are inflated by 30% on average.
6209 Use --no-globals to turn this feature off. Etags can also tag
6210 variables which are members of structure-like constructs, but it does
6211 not by default. Use --members to turn this feature on.
6212
6213 *** C++ member functions are now recognized as tags.
6214
6215 *** Java is tagged like C++. In addition, "extends" and "implements"
6216 constructs are tagged. Files are recognised by the extension .java.
6217
6218 *** Etags can now handle programs written in Postscript. Files are
6219 recognised by the extensions .ps and .pdb (Postscript with C syntax).
6220 In Postscript, tags are lines that start with a slash.
6221
6222 *** Etags now handles Objective C and Objective C++ code. The usual C and
6223 C++ tags are recognized in these languages; in addition, etags
6224 recognizes special Objective C syntax for classes, class categories,
6225 methods and protocols.
6226
6227 *** Etags also handles Cobol. Files are recognised by the extension
6228 .cobol. The tagged lines are those containing a word that begins in
6229 column 8 and ends in a full stop, i.e. anything that could be a
6230 paragraph name.
6231
6232 *** Regexps in Etags now support intervals, as in ed or grep. The syntax of
6233 an interval is \{M,N\}, and it means to match the preceding expression
6234 at least M times and as many as N times.
6235
6236 ** The format for specifying a custom format for time-stamp to insert
6237 in files has changed slightly.
6238
6239 With the new enhancements to the functionality of format-time-string,
6240 time-stamp-format will change to be eventually compatible with it.
6241 This conversion is being done in two steps to maintain compatibility
6242 with old time-stamp-format values.
6243
6244 In the new scheme, alternate case is signified by the number-sign
6245 (`#') modifier, rather than changing the case of the format character.
6246 This feature is as yet incompletely implemented for compatibility
6247 reasons.
6248
6249 In the old time-stamp-format, all numeric fields defaulted to their
6250 natural width. (With format-time-string, each format has a
6251 fixed-width default.) In this version, you can specify the colon
6252 (`:') modifier to a numeric conversion to mean "give me the historical
6253 time-stamp-format width default." Do not use colon if you are
6254 specifying an explicit width, as in "%02d".
6255
6256 Numbers are no longer truncated to the requested width, except in the
6257 case of "%02y", which continues to give a two-digit year. Digit
6258 truncation probably wasn't being used for anything else anyway.
6259
6260 The new formats will work with old versions of Emacs. New formats are
6261 being recommended now to allow time-stamp-format to change in the
6262 future to be compatible with format-time-string. The new forms being
6263 recommended now will continue to work then.
6264
6265 See the documentation string for the variable time-stamp-format for
6266 details.
6267
6268 ** There are some additional major modes:
6269
6270 dcl-mode, for editing VMS DCL files.
6271 m4-mode, for editing files of m4 input.
6272 meta-mode, for editing MetaFont and MetaPost source files.
6273
6274 ** In Shell mode, the command shell-copy-environment-variable lets you
6275 copy the value of a specified environment variable from the subshell
6276 into Emacs.
6277
6278 ** New Lisp packages include:
6279
6280 *** battery.el displays battery status for laptops.
6281
6282 *** M-x bruce (named after Lenny Bruce) is a program that might
6283 be used for adding some indecent words to your email.
6284
6285 *** M-x crisp-mode enables an emulation for the CRiSP editor.
6286
6287 *** M-x dirtrack arranges for better tracking of directory changes
6288 in shell buffers.
6289
6290 *** The new library elint.el provides for linting of Emacs Lisp code.
6291 See the documentation for `elint-initialize', `elint-current-buffer'
6292 and `elint-defun'.
6293
6294 *** M-x expand-add-abbrevs defines a special kind of abbrev which is
6295 meant for programming constructs. These abbrevs expand like ordinary
6296 ones, when you type SPC, but only at the end of a line and not within
6297 strings or comments.
6298
6299 These abbrevs can act as templates: you can define places within an
6300 abbrev for insertion of additional text. Once you expand the abbrev,
6301 you can then use C-x a p and C-x a n to move back and forth to these
6302 insertion points. Thus you can conveniently insert additional text
6303 at these points.
6304
6305 *** filecache.el remembers the location of files so that you
6306 can visit them by short forms of their names.
6307
6308 *** find-func.el lets you find the definition of the user-loaded
6309 Emacs Lisp function at point.
6310
6311 *** M-x handwrite converts text to a "handwritten" picture.
6312
6313 *** M-x iswitchb-buffer is a command for switching to a buffer, much like
6314 switch-buffer, but it reads the argument in a more helpful way.
6315
6316 *** M-x landmark implements a neural network for landmark learning.
6317
6318 *** M-x locate provides a convenient interface to the `locate' program.
6319
6320 *** M4 mode is a new mode for editing files of m4 input.
6321
6322 *** mantemp.el creates C++ manual template instantiations
6323 from the GCC error messages which indicate which instantiations are needed.
6324
6325 *** mouse-copy.el provides a one-click copy and move feature.
6326 You can drag a region with M-mouse-1, and it is automatically
6327 inserted at point. M-Shift-mouse-1 deletes the text from its
6328 original place after inserting the copy.
6329
6330 *** mouse-drag.el lets you do scrolling by dragging Mouse-2
6331 on the buffer.
6332
6333 You click the mouse and move; that distance either translates into the
6334 velocity to scroll (with mouse-drag-throw) or the distance to scroll
6335 (with mouse-drag-drag). Horizontal scrolling is enabled when needed.
6336
6337 Enable mouse-drag with:
6338 (global-set-key [down-mouse-2] 'mouse-drag-throw)
6339 -or-
6340 (global-set-key [down-mouse-2] 'mouse-drag-drag)
6341
6342 *** mspools.el is useful for determining which mail folders have
6343 mail waiting to be read in them. It works with procmail.
6344
6345 *** Octave mode is a major mode for editing files of input for Octave.
6346 It comes with a facility for communicating with an Octave subprocess.
6347
6348 *** ogonek
6349
6350 The ogonek package provides functions for changing the coding of
6351 Polish diacritic characters in buffers. Codings known from various
6352 platforms are supported such as ISO8859-2, Mazovia, IBM Latin2, and
6353 TeX. For example, you can change the coding from Mazovia to
6354 ISO8859-2. Another example is a change of coding from ISO8859-2 to
6355 prefix notation (in which `/a' stands for the aogonek character, for
6356 instance) and vice versa.
6357
6358 To use this package load it using
6359 M-x load-library [enter] ogonek
6360 Then, you may get an explanation by calling one of
6361 M-x ogonek-jak -- in Polish
6362 M-x ogonek-how -- in English
6363 The info specifies the commands and variables provided as well as the
6364 ways of customization in `.emacs'.
6365
6366 *** Interface to ph.
6367
6368 Emacs provides a client interface to CCSO Nameservers (ph/qi)
6369
6370 The CCSO nameserver is used in many universities to provide directory
6371 services about people. ph.el provides a convenient Emacs interface to
6372 these servers.
6373
6374 *** uce.el is useful for replying to unsolicited commercial email.
6375
6376 *** vcursor.el implements a "virtual cursor" feature.
6377 You can move the virtual cursor with special commands
6378 while the real cursor does not move.
6379
6380 *** webjump.el is a "hot list" package which you can set up
6381 for visiting your favorite web sites.
6382
6383 *** M-x winner-mode is a minor mode which saves window configurations,
6384 so you can move back to other configurations that you have recently used.
6385
6386 ** movemail change
6387
6388 Movemail no longer needs to be installed setuid root in order for POP
6389 mail retrieval to function properly. This is because it no longer
6390 supports the RPOP (reserved-port POP) protocol; instead, it uses the
6391 user's POP password to authenticate to the mail server.
6392
6393 This change was made earlier, but not reported in NEWS before.
6394 \f
6395 * Emacs 20.1 changes for MS-DOS and MS-Windows.
6396
6397 ** Changes in handling MS-DOS/MS-Windows text files.
6398
6399 Emacs handles three different conventions for representing
6400 end-of-line: CRLF for MSDOS, LF for Unix and GNU, and CR (used on the
6401 Macintosh). Emacs determines which convention is used in a specific
6402 file based on the contents of that file (except for certain special
6403 file names), and when it saves the file, it uses the same convention.
6404
6405 To save the file and change the end-of-line convention, you can use
6406 C-x RET f (set-buffer-file-coding-system) to specify a different
6407 coding system for the buffer. Then, when you save the file, the newly
6408 specified coding system will take effect. For example, to save with
6409 LF, specify undecided-unix (or some other ...-unix coding system); to
6410 save with CRLF, specify undecided-dos.
6411 \f
6412 * Lisp Changes in Emacs 20.1
6413
6414 ** Byte-compiled files made with Emacs 20 will, in general, work in
6415 Emacs 19 as well, as long as the source code runs in Emacs 19. And
6416 vice versa: byte-compiled files made with Emacs 19 should also run in
6417 Emacs 20, as long as the program itself works in Emacs 20.
6418
6419 ** Windows-specific functions and variables have been renamed
6420 to start with w32- instead of win32-.
6421
6422 In hacker language, calling something a "win" is a form of praise. We
6423 don't want to praise a non-free Microsoft system, so we don't call it
6424 "win".
6425
6426 ** Basic Lisp changes
6427
6428 *** A symbol whose name starts with a colon now automatically
6429 evaluates to itself. Therefore such a symbol can be used as a constant.
6430
6431 *** The defined purpose of `defconst' has been changed. It should now
6432 be used only for values that should not be changed whether by a program
6433 or by the user.
6434
6435 The actual behavior of defconst has not been changed.
6436
6437 *** There are new macros `when' and `unless'
6438
6439 (when CONDITION BODY...) is short for (if CONDITION (progn BODY...))
6440 (unless CONDITION BODY...) is short for (if CONDITION nil BODY...)
6441
6442 *** Emacs now defines functions caar, cadr, cdar and cddr with their
6443 usual Lisp meanings. For example, caar returns the car of the car of
6444 its argument.
6445
6446 *** equal, when comparing strings, now ignores their text properties.
6447
6448 *** The new function `functionp' tests whether an object is a function.
6449
6450 *** arrayp now returns t for char-tables and bool-vectors.
6451
6452 *** Certain primitives which use characters (as integers) now get an
6453 error if the integer is not a valid character code. These primitives
6454 include insert-char, char-to-string, and the %c construct in the
6455 `format' function.
6456
6457 *** The `require' function now insists on adding a suffix, either .el
6458 or .elc, to the file name. Thus, (require 'foo) will not use a file
6459 whose name is just foo. It insists on foo.el or foo.elc.
6460
6461 *** The `autoload' function, when the file name does not contain
6462 either a directory name or the suffix .el or .elc, insists on
6463 adding one of these suffixes.
6464
6465 *** string-to-number now takes an optional second argument BASE
6466 which specifies the base to use when converting an integer.
6467 If BASE is omitted, base 10 is used.
6468
6469 We have not implemented other radices for floating point numbers,
6470 because that would be much more work and does not seem useful.
6471
6472 *** substring now handles vectors as well as strings.
6473
6474 *** The Common Lisp function eql is no longer defined normally.
6475 You must load the `cl' library to define it.
6476
6477 *** The new macro `with-current-buffer' lets you evaluate an expression
6478 conveniently with a different current buffer. It looks like this:
6479
6480 (with-current-buffer BUFFER BODY-FORMS...)
6481
6482 BUFFER is the expression that says which buffer to use.
6483 BODY-FORMS say what to do in that buffer.
6484
6485 *** The new primitive `save-current-buffer' saves and restores the
6486 choice of current buffer, like `save-excursion', but without saving or
6487 restoring the value of point or the mark. `with-current-buffer'
6488 works using `save-current-buffer'.
6489
6490 *** The new macro `with-temp-file' lets you do some work in a new buffer and
6491 write the output to a specified file. Like `progn', it returns the value
6492 of the last form.
6493
6494 *** The new macro `with-temp-buffer' lets you do some work in a new buffer,
6495 which is discarded after use. Like `progn', it returns the value of the
6496 last form. If you wish to return the buffer contents, use (buffer-string)
6497 as the last form.
6498
6499 *** The new function split-string takes a string, splits it at certain
6500 characters, and returns a list of the substrings in between the
6501 matches.
6502
6503 For example, (split-string "foo bar lose" " +") returns ("foo" "bar" "lose").
6504
6505 *** The new macro with-output-to-string executes some Lisp expressions
6506 with standard-output set up so that all output feeds into a string.
6507 Then it returns that string.
6508
6509 For example, if the current buffer name is `foo',
6510
6511 (with-output-to-string
6512 (princ "The buffer is ")
6513 (princ (buffer-name)))
6514
6515 returns "The buffer is foo".
6516
6517 ** Non-ASCII characters are now supported, if enable-multibyte-characters
6518 is non-nil.
6519
6520 These characters have character codes above 256. When inserted in the
6521 buffer or stored in a string, they are represented as multibyte
6522 characters that occupy several buffer positions each.
6523
6524 *** When enable-multibyte-characters is non-nil, a single character in
6525 a buffer or string can be two or more bytes (as many as four).
6526
6527 Buffers and strings are still made up of unibyte elements;
6528 character positions and string indices are always measured in bytes.
6529 Therefore, moving forward one character can increase the buffer
6530 position by 2, 3 or 4. The function forward-char moves by whole
6531 characters, and therefore is no longer equivalent to
6532 (lambda (n) (goto-char (+ (point) n))).
6533
6534 ASCII characters (codes 0 through 127) are still single bytes, always.
6535 Sequences of byte values 128 through 255 are used to represent
6536 non-ASCII characters. These sequences are called "multibyte
6537 characters".
6538
6539 The first byte of a multibyte character is always in the range 128
6540 through 159 (octal 0200 through 0237). These values are called
6541 "leading codes". The second and subsequent bytes are always in the
6542 range 160 through 255 (octal 0240 through 0377). The first byte, the
6543 leading code, determines how many bytes long the sequence is.
6544
6545 *** The function forward-char moves over characters, and therefore
6546 (forward-char 1) may increase point by more than 1 if it moves over a
6547 multibyte character. Likewise, delete-char always deletes a
6548 character, which may be more than one buffer position.
6549
6550 This means that some Lisp programs, which assume that a character is
6551 always one buffer position, need to be changed.
6552
6553 However, all ASCII characters are always one buffer position.
6554
6555 *** The regexp [\200-\377] no longer matches all non-ASCII characters,
6556 because when enable-multibyte-characters is non-nil, these characters
6557 have codes that are not in the range octal 200 to octal 377. However,
6558 the regexp [^\000-\177] does match all non-ASCII characters,
6559 guaranteed.
6560
6561 *** The function char-boundary-p returns non-nil if position POS is
6562 between two characters in the buffer (not in the middle of a
6563 character).
6564
6565 When the value is non-nil, it says what kind of character follows POS:
6566
6567 0 if POS is at an ASCII character or at the end of range,
6568 1 if POS is before a 2-byte length multi-byte form,
6569 2 if POS is at a head of 3-byte length multi-byte form,
6570 3 if POS is at a head of 4-byte length multi-byte form,
6571 4 if POS is at a head of multi-byte form of a composite character.
6572
6573 *** The function char-bytes returns how many bytes the character CHAR uses.
6574
6575 *** Strings can contain multibyte characters. The function
6576 `length' returns the string length counting bytes, which may be
6577 more than the number of characters.
6578
6579 You can include a multibyte character in a string constant by writing
6580 it literally. You can also represent it with a hex escape,
6581 \xNNNNNNN..., using as many digits as necessary. Any character which
6582 is not a valid hex digit terminates this construct. If you want to
6583 follow it with a character that is a hex digit, write backslash and
6584 newline in between; that will terminate the hex escape.
6585
6586 *** The function concat-chars takes arguments which are characters
6587 and returns a string containing those characters.
6588
6589 *** The function sref access a multibyte character in a string.
6590 (sref STRING INDX) returns the character in STRING at INDEX. INDEX
6591 counts from zero. If INDEX is at a position in the middle of a
6592 character, sref signals an error.
6593
6594 *** The function chars-in-string returns the number of characters
6595 in a string. This is less than the length of the string, if the
6596 string contains multibyte characters (the length counts bytes).
6597
6598 *** The function chars-in-region returns the number of characters
6599 in a region from BEG to END. This is less than (- END BEG) if the
6600 region contains multibyte characters (the length counts bytes).
6601
6602 *** The function string-to-list converts a string to a list of
6603 the characters in it. string-to-vector converts a string
6604 to a vector of the characters in it.
6605
6606 *** The function store-substring alters part of the contents
6607 of a string. You call it as follows:
6608
6609 (store-substring STRING IDX OBJ)
6610
6611 This says to alter STRING, by storing OBJ starting at index IDX in
6612 STRING. OBJ may be either a character or a (smaller) string.
6613 This function really does alter the contents of STRING.
6614 Since it is impossible to change the length of an existing string,
6615 it is an error if OBJ doesn't fit within STRING's actual length.
6616
6617 *** char-width returns the width (in columns) of the character CHAR,
6618 if it were displayed in the current buffer and the selected window.
6619
6620 *** string-width returns the width (in columns) of the text in STRING,
6621 if it were displayed in the current buffer and the selected window.
6622
6623 *** truncate-string-to-width shortens a string, if necessary,
6624 to fit within a certain number of columns. (Of course, it does
6625 not alter the string that you give it; it returns a new string
6626 which contains all or just part of the existing string.)
6627
6628 (truncate-string-to-width STR END-COLUMN &optional START-COLUMN PADDING)
6629
6630 This returns the part of STR up to column END-COLUMN.
6631
6632 The optional argument START-COLUMN specifies the starting column.
6633 If this is non-nil, then the first START-COLUMN columns of the string
6634 are not included in the resulting value.
6635
6636 The optional argument PADDING, if non-nil, is a padding character to be added
6637 at the beginning and end the resulting string, to extend it to exactly
6638 WIDTH columns. If PADDING is nil, that means do not pad; then, if STRING
6639 is narrower than WIDTH, the value is equal to STRING.
6640
6641 If PADDING and START-COLUMN are both non-nil, and if there is no clean
6642 place in STRING that corresponds to START-COLUMN (because one
6643 character extends across that column), then the padding character
6644 PADDING is added one or more times at the beginning of the result
6645 string, so that its columns line up as if it really did start at
6646 column START-COLUMN.
6647
6648 *** When the functions in the list after-change-functions are called,
6649 the third argument is the number of bytes in the pre-change text, not
6650 necessarily the number of characters. It is, in effect, the
6651 difference in buffer position between the beginning and the end of the
6652 changed text, before the change.
6653
6654 *** The characters Emacs uses are classified in various character
6655 sets, each of which has a name which is a symbol. In general there is
6656 one character set for each script, not for each language.
6657
6658 **** The function charsetp tests whether an object is a character set name.
6659
6660 **** The variable charset-list holds a list of character set names.
6661
6662 **** char-charset, given a character code, returns the name of the character
6663 set that the character belongs to. (The value is a symbol.)
6664
6665 **** split-char, given a character code, returns a list containing the
6666 name of the character set, followed by one or two byte-values
6667 which identify the character within that character set.
6668
6669 **** make-char, given a character set name and one or two subsequent
6670 byte-values, constructs a character code. This is roughly the
6671 opposite of split-char.
6672
6673 **** find-charset-region returns a list of the character sets
6674 of all the characters between BEG and END.
6675
6676 **** find-charset-string returns a list of the character sets
6677 of all the characters in a string.
6678
6679 *** Here are the Lisp facilities for working with coding systems
6680 and specifying coding systems.
6681
6682 **** The function coding-system-list returns a list of all coding
6683 system names (symbols). With optional argument t, it returns a list
6684 of all distinct base coding systems, not including variants.
6685 (Variant coding systems are those like latin-1-dos, latin-1-unix
6686 and latin-1-mac which specify the end-of-line conversion as well
6687 as what to do about code conversion.)
6688
6689 **** coding-system-p tests a symbol to see if it is a coding system
6690 name. It returns t if so, nil if not.
6691
6692 **** file-coding-system-alist specifies which coding systems to use
6693 for certain file names. It works like network-coding-system-alist,
6694 except that the PATTERN is matched against the file name.
6695
6696 Each element has the format (PATTERN . VAL), where PATTERN determines
6697 which file names the element applies to. PATTERN should be a regexp
6698 to match against a file name.
6699
6700 VAL is a coding system, a cons cell containing two coding systems, or
6701 a function symbol. If VAL is a coding system, it is used for both
6702 decoding what received from the network stream and encoding what sent
6703 to the network stream. If VAL is a cons cell containing two coding
6704 systems, the car specifies the coding system for decoding, and the cdr
6705 specifies the coding system for encoding.
6706
6707 If VAL is a function symbol, the function must return a coding system
6708 or a cons cell containing two coding systems, which is used as above.
6709
6710 **** The variable network-coding-system-alist specifies
6711 the coding system to use for network sockets.
6712
6713 Each element has the format (PATTERN . VAL), where PATTERN determines
6714 which network sockets the element applies to. PATTERN should be
6715 either a port number or a regular expression matching some network
6716 service names.
6717
6718 VAL is a coding system, a cons cell containing two coding systems, or
6719 a function symbol. If VAL is a coding system, it is used for both
6720 decoding what received from the network stream and encoding what sent
6721 to the network stream. If VAL is a cons cell containing two coding
6722 systems, the car specifies the coding system for decoding, and the cdr
6723 specifies the coding system for encoding.
6724
6725 If VAL is a function symbol, the function must return a coding system
6726 or a cons cell containing two coding systems, which is used as above.
6727
6728 **** process-coding-system-alist specifies which coding systems to use
6729 for certain subprocess. It works like network-coding-system-alist,
6730 except that the PATTERN is matched against the program name used to
6731 start the subprocess.
6732
6733 **** The variable default-process-coding-system specifies the coding
6734 systems to use for subprocess (and net connection) input and output,
6735 when nothing else specifies what to do. The value is a cons cell
6736 (OUTPUT-CODING . INPUT-CODING). OUTPUT-CODING applies to output
6737 to the subprocess, and INPUT-CODING applies to input from it.
6738
6739 **** The variable coding-system-for-write, if non-nil, specifies the
6740 coding system to use for writing a file, or for output to a synchronous
6741 subprocess.
6742
6743 It also applies to any asynchronous subprocess or network connection,
6744 but in a different way: the value of coding-system-for-write when you
6745 start the subprocess or connection affects that subprocess or
6746 connection permanently or until overridden.
6747
6748 The variable coding-system-for-write takes precedence over
6749 file-coding-system-alist, process-coding-system-alist and
6750 network-coding-system-alist, and all other methods of specifying a
6751 coding system for output. But most of the time this variable is nil.
6752 It exists so that Lisp programs can bind it to a specific coding
6753 system for one operation at a time.
6754
6755 **** coding-system-for-read applies similarly to input from
6756 files, subprocesses or network connections.
6757
6758 **** The function process-coding-system tells you what
6759 coding systems(s) an existing subprocess is using.
6760 The value is a cons cell,
6761 (DECODING-CODING-SYSTEM . ENCODING-CODING-SYSTEM)
6762 where DECODING-CODING-SYSTEM is used for decoding output from
6763 the subprocess, and ENCODING-CODING-SYSTEM is used for encoding
6764 input to the subprocess.
6765
6766 **** The function set-process-coding-system can be used to
6767 change the coding systems in use for an existing subprocess.
6768
6769 ** Emacs has a new facility to help users manage the many
6770 customization options. To make a Lisp program work with this facility,
6771 you need to use the new macros defgroup and defcustom.
6772
6773 You use defcustom instead of defvar, for defining a user option
6774 variable. The difference is that you specify two additional pieces of
6775 information (usually): the "type" which says what values are
6776 legitimate, and the "group" which specifies the hierarchy for
6777 customization.
6778
6779 Thus, instead of writing
6780
6781 (defvar foo-blurgoze nil
6782 "*Non-nil means that foo will act very blurgozely.")
6783
6784 you would now write this:
6785
6786 (defcustom foo-blurgoze nil
6787 "*Non-nil means that foo will act very blurgozely."
6788 :type 'boolean
6789 :group foo)
6790
6791 The type `boolean' means that this variable has only
6792 two meaningful states: nil and non-nil. Other type values
6793 describe other possibilities; see the manual for Custom
6794 for a description of them.
6795
6796 The "group" argument is used to specify a group which the option
6797 should belong to. You define a new group like this:
6798
6799 (defgroup ispell nil
6800 "Spell checking using Ispell."
6801 :group 'processes)
6802
6803 The "group" argument in defgroup specifies the parent group. The root
6804 group is called `emacs'; it should not contain any variables itself,
6805 but only other groups. The immediate subgroups of `emacs' correspond
6806 to the keywords used by C-h p. Under these subgroups come
6807 second-level subgroups that belong to individual packages.
6808
6809 Each Emacs package should have its own set of groups. A simple
6810 package should have just one group; a more complex package should
6811 have a hierarchy of its own groups. The sole or root group of a
6812 package should be a subgroup of one or more of the "keyword"
6813 first-level subgroups.
6814
6815 ** New `widget' library for inserting UI components in buffers.
6816
6817 This library, used by the new custom library, is documented in a
6818 separate manual that accompanies Emacs.
6819
6820 ** easy-mmode
6821
6822 The easy-mmode package provides macros and functions that make
6823 developing minor modes easier. Roughly, the programmer has to code
6824 only the functionality of the minor mode. All the rest--toggles,
6825 predicate, and documentation--can be done in one call to the macro
6826 `easy-mmode-define-minor-mode' (see the documentation). See also
6827 `easy-mmode-define-keymap'.
6828
6829 ** Text property changes
6830
6831 *** The `intangible' property now works on overlays as well as on a
6832 text property.
6833
6834 *** The new functions next-char-property-change and
6835 previous-char-property-change scan through the buffer looking for a
6836 place where either a text property or an overlay might change. The
6837 functions take two arguments, POSITION and LIMIT. POSITION is the
6838 starting position for the scan. LIMIT says where to stop the scan.
6839
6840 If no property change is found before LIMIT, the value is LIMIT. If
6841 LIMIT is nil, scan goes to the beginning or end of the accessible part
6842 of the buffer. If no property change is found, the value is the
6843 position of the beginning or end of the buffer.
6844
6845 *** In the `local-map' text property or overlay property, the property
6846 value can now be a symbol whose function definition is a keymap. This
6847 is an alternative to using the keymap itself.
6848
6849 ** Changes in invisibility features
6850
6851 *** Isearch can now temporarily show parts of the buffer which are
6852 hidden by an overlay with a invisible property, when the search match
6853 is inside that portion of the buffer. To enable this the overlay
6854 should have a isearch-open-invisible property which is a function that
6855 would be called having the overlay as an argument, the function should
6856 make the overlay visible.
6857
6858 During incremental search the overlays are shown by modifying the
6859 invisible and intangible properties, if beside this more actions are
6860 needed the overlay should have a isearch-open-invisible-temporary
6861 which is a function. The function is called with 2 arguments: one is
6862 the overlay and the second is nil when it should show the overlay and
6863 t when it should hide it.
6864
6865 *** add-to-invisibility-spec, remove-from-invisibility-spec
6866
6867 Modes that use overlays to hide portions of a buffer should set the
6868 invisible property of the overlay to the mode's name (or another symbol)
6869 and modify the `buffer-invisibility-spec' to include that symbol.
6870 Use `add-to-invisibility-spec' and `remove-from-invisibility-spec' to
6871 manipulate the `buffer-invisibility-spec'.
6872 Here is an example of how to do this:
6873
6874 ;; If we want to display an ellipsis:
6875 (add-to-invisibility-spec '(my-symbol . t))
6876 ;; If you don't want ellipsis:
6877 (add-to-invisibility-spec 'my-symbol)
6878
6879 ...
6880 (overlay-put (make-overlay beginning end) 'invisible 'my-symbol)
6881
6882 ...
6883 ;; When done with the overlays:
6884 (remove-from-invisibility-spec '(my-symbol . t))
6885 ;; Or respectively:
6886 (remove-from-invisibility-spec 'my-symbol)
6887
6888 ** Changes in syntax parsing.
6889
6890 *** The syntax-directed buffer-scan functions (such as
6891 `parse-partial-sexp', `forward-word' and similar functions) can now
6892 obey syntax information specified by text properties, if the variable
6893 `parse-sexp-lookup-properties' is non-nil.
6894
6895 If the value of `parse-sexp-lookup-properties' is nil, the behavior
6896 is as before: the syntax-table of the current buffer is always
6897 used to determine the syntax of the character at the position.
6898
6899 When `parse-sexp-lookup-properties' is non-nil, the syntax of a
6900 character in the buffer is calculated thus:
6901
6902 a) if the `syntax-table' text-property of that character
6903 is a cons, this cons becomes the syntax-type;
6904
6905 Valid values of `syntax-table' text-property are: nil, a valid
6906 syntax-table, and a valid syntax-table element, i.e.,
6907 a cons cell of the form (SYNTAX-CODE . MATCHING-CHAR).
6908
6909 b) if the character's `syntax-table' text-property
6910 is a syntax table, this syntax table is used
6911 (instead of the syntax-table of the current buffer) to
6912 determine the syntax type of the character.
6913
6914 c) otherwise the syntax-type is determined by the syntax-table
6915 of the current buffer.
6916
6917 *** The meaning of \s in regular expressions is also affected by the
6918 value of `parse-sexp-lookup-properties'. The details are the same as
6919 for the syntax-directed buffer-scan functions.
6920
6921 *** There are two new syntax-codes, `!' and `|' (numeric values 14
6922 and 15). A character with a code `!' starts a comment which is ended
6923 only by another character with the same code (unless quoted). A
6924 character with a code `|' starts a string which is ended only by
6925 another character with the same code (unless quoted).
6926
6927 These codes are mainly meant for use as values of the `syntax-table'
6928 text property.
6929
6930 *** The function `parse-partial-sexp' has new semantics for the sixth
6931 arg COMMENTSTOP. If it is `syntax-table', parse stops after the start
6932 of a comment or a string, or after end of a comment or a string.
6933
6934 *** The state-list which the return value from `parse-partial-sexp'
6935 (and can also be used as an argument) now has an optional ninth
6936 element: the character address of the start of last comment or string;
6937 nil if none. The fourth and eighth elements have special values if the
6938 string/comment is started by a "!" or "|" syntax-code.
6939
6940 *** Since new features of `parse-partial-sexp' allow a complete
6941 syntactic parsing, `font-lock' no longer supports
6942 `font-lock-comment-start-regexp'.
6943
6944 ** Changes in face features
6945
6946 *** The face functions are now unconditionally defined in Emacs, even
6947 if it does not support displaying on a device that supports faces.
6948
6949 *** The function face-documentation returns the documentation string
6950 of a face (or nil if it doesn't have one).
6951
6952 *** The function face-bold-p returns t if a face should be bold.
6953 set-face-bold-p sets that flag.
6954
6955 *** The function face-italic-p returns t if a face should be italic.
6956 set-face-italic-p sets that flag.
6957
6958 *** You can now specify foreground and background colors for text
6959 by adding elements of the form (foreground-color . COLOR-NAME)
6960 and (background-color . COLOR-NAME) to the list of faces in
6961 the `face' property (either the character's text property or an
6962 overlay property).
6963
6964 This means that you no longer need to create named faces to use
6965 arbitrary colors in a Lisp package.
6966
6967 ** Changes in file-handling functions
6968
6969 *** File-access primitive functions no longer discard an extra redundant
6970 directory name from the beginning of the file name. In other words,
6971 they no longer do anything special with // or /~. That conversion
6972 is now done only in substitute-in-file-name.
6973
6974 This makes it possible for a Lisp program to open a file whose name
6975 begins with ~.
6976
6977 *** If copy-file is unable to set the date of the output file,
6978 it now signals an error with the condition file-date-error.
6979
6980 *** The inode number returned by file-attributes may be an integer (if
6981 the number fits in a Lisp integer) or a list of integers.
6982
6983 *** insert-file-contents can now read from a special file,
6984 as long as the arguments VISIT and REPLACE are nil.
6985
6986 *** The RAWFILE arg to find-file-noselect, if non-nil, now suppresses
6987 character code conversion as well as other things.
6988
6989 Meanwhile, this feature does work with remote file names
6990 (formerly it did not).
6991
6992 *** Lisp packages which create temporary files should use the TMPDIR
6993 environment variable to decide which directory to put them in.
6994
6995 *** interpreter-mode-alist elements now specify regexps
6996 instead of constant strings.
6997
6998 *** expand-file-name no longer treats `//' or `/~' specially. It used
6999 to delete all the text of a file name up through the first slash of
7000 any `//' or `/~' sequence. Now it passes them straight through.
7001
7002 substitute-in-file-name continues to treat those sequences specially,
7003 in the same way as before.
7004
7005 *** The variable `format-alist' is more general now.
7006 The FROM-FN and TO-FN in a format definition can now be strings
7007 which specify shell commands to use as filters to perform conversion.
7008
7009 *** The new function access-file tries to open a file, and signals an
7010 error if that fails. If the open succeeds, access-file does nothing
7011 else, and returns nil.
7012
7013 *** The function insert-directory now signals an error if the specified
7014 directory cannot be listed.
7015
7016 ** Changes in minibuffer input
7017
7018 *** The functions read-buffer, read-variable, read-command, read-string
7019 read-file-name, read-from-minibuffer and completing-read now take an
7020 additional argument which specifies the default value. If this
7021 argument is non-nil, it should be a string; that string is used in two
7022 ways:
7023
7024 It is returned if the user enters empty input.
7025 It is available through the history command M-n.
7026
7027 *** The functions read-string, read-from-minibuffer,
7028 read-no-blanks-input and completing-read now take an additional
7029 argument INHERIT-INPUT-METHOD. If this is non-nil, then the
7030 minibuffer inherits the current input method and the setting of
7031 enable-multibyte-characters from the previously current buffer.
7032
7033 In an interactive spec, you can use M instead of s to read an
7034 argument in this way.
7035
7036 *** All minibuffer input functions discard text properties
7037 from the text you enter in the minibuffer, unless the variable
7038 minibuffer-allow-text-properties is non-nil.
7039
7040 ** Echo area features
7041
7042 *** Clearing the echo area now runs the normal hook
7043 echo-area-clear-hook. Note that the echo area can be used while the
7044 minibuffer is active; in that case, the minibuffer is still active
7045 after the echo area is cleared.
7046
7047 *** The function current-message returns the message currently displayed
7048 in the echo area, or nil if there is none.
7049
7050 ** Keyboard input features
7051
7052 *** tty-erase-char is a new variable that reports which character was
7053 set up as the terminal's erase character when time Emacs was started.
7054
7055 *** num-nonmacro-input-events is the total number of input events
7056 received so far from the terminal. It does not count those generated
7057 by keyboard macros.
7058
7059 ** Frame-related changes
7060
7061 *** make-frame runs the normal hook before-make-frame-hook just before
7062 creating a frame, and just after creating a frame it runs the abnormal
7063 hook after-make-frame-functions with the new frame as arg.
7064
7065 *** The new hook window-configuration-change-hook is now run every time
7066 the window configuration has changed. The frame whose configuration
7067 has changed is the selected frame when the hook is run.
7068
7069 *** Each frame now independently records the order for recently
7070 selected buffers, in its buffer-list frame parameter, so that the
7071 value of other-buffer is now based on the buffers recently displayed
7072 in the selected frame.
7073
7074 *** The value of the frame parameter vertical-scroll-bars
7075 is now `left', `right' or nil. A non-nil value specifies
7076 which side of the window to put the scroll bars on.
7077
7078 ** X Windows features
7079
7080 *** You can examine X resources for other applications by binding
7081 x-resource-class around a call to x-get-resource. The usual value of
7082 x-resource-class is "Emacs", which is the correct value for Emacs.
7083
7084 *** In menus, checkboxes and radio buttons now actually work.
7085 The menu displays the current status of the box or button.
7086
7087 *** The function x-list-fonts now takes an optional fourth argument
7088 MAXIMUM which sets a limit on how many matching fonts to return.
7089 A smaller value of MAXIMUM makes the function faster.
7090
7091 If the only question is whether *any* font matches the pattern,
7092 it is good to supply 1 for this argument.
7093
7094 ** Subprocess features
7095
7096 *** A reminder: it is no longer necessary for subprocess filter
7097 functions and sentinels to do save-match-data, because Emacs does this
7098 automatically.
7099
7100 *** The new function shell-command-to-string executes a shell command
7101 and returns the output from the command as a string.
7102
7103 *** The new function process-contact returns t for a child process,
7104 and (HOSTNAME SERVICE) for a net connection.
7105
7106 ** An error in running pre-command-hook or post-command-hook
7107 does clear the variable to nil. The documentation was wrong before.
7108
7109 ** In define-key-after, if AFTER is t, the new binding now always goes
7110 at the end of the keymap. If the keymap is a menu, this means it
7111 goes after the other menu items.
7112
7113 ** If you have a program that makes several changes in the same area
7114 of the buffer, you can use the macro combine-after-change-calls
7115 around that Lisp code to make it faster when after-change hooks
7116 are in use.
7117
7118 The macro arranges to call the after-change functions just once for a
7119 series of several changes--if that seems safe.
7120
7121 Don't alter the variables after-change-functions and
7122 after-change-function within the body of a combine-after-change-calls
7123 form.
7124
7125 ** If you define an abbrev (with define-abbrev) whose EXPANSION
7126 is not a string, then the abbrev does not expand in the usual sense,
7127 but its hook is still run.
7128
7129 ** Normally, the Lisp debugger is not used (even if you have enabled it)
7130 for errors that are handled by condition-case.
7131
7132 If you set debug-on-signal to a non-nil value, then the debugger is called
7133 regardless of whether there is a handler for the condition. This is
7134 useful for debugging problems that happen inside of a condition-case.
7135
7136 This mode of operation seems to be unreliable in other ways. Errors that
7137 are normal and ought to be handled, perhaps in timers or process
7138 filters, will instead invoke the debugger. So don't say you weren't
7139 warned.
7140
7141 ** The new variable ring-bell-function lets you specify your own
7142 way for Emacs to "ring the bell".
7143
7144 ** If run-at-time's TIME argument is t, the action is repeated at
7145 integral multiples of REPEAT from the epoch; this is useful for
7146 functions like display-time.
7147
7148 ** You can use the function locate-library to find the precise file
7149 name of a Lisp library. This isn't new, but wasn't documented before.
7150
7151 ** Commands for entering view mode have new optional arguments that
7152 can be used from Lisp. Low-level entrance to and exit from view mode
7153 is done by functions view-mode-enter and view-mode-exit.
7154
7155 ** batch-byte-compile-file now makes Emacs return a nonzero status code
7156 if there is an error in compilation.
7157
7158 ** pop-to-buffer, switch-to-buffer-other-window and
7159 switch-to-buffer-other-frame now accept an additional optional
7160 argument NORECORD, much like switch-to-buffer. If it is non-nil,
7161 they don't put the buffer at the front of the buffer list.
7162
7163 ** If your .emacs file leaves the *scratch* buffer non-empty,
7164 Emacs does not display the startup message, so as to avoid changing
7165 the *scratch* buffer.
7166
7167 ** The new function regexp-opt returns an efficient regexp to match a string.
7168 The arguments are STRINGS and (optionally) PAREN. This function can be used
7169 where regexp matching or searching is intensively used and speed is important,
7170 e.g., in Font Lock mode.
7171
7172 ** The variable buffer-display-count is local to each buffer,
7173 and is incremented each time the buffer is displayed in a window.
7174 It starts at 0 when the buffer is created.
7175
7176 ** The new function compose-mail starts composing a mail message
7177 using the user's chosen mail composition agent (specified with the
7178 variable mail-user-agent). It has variants compose-mail-other-window
7179 and compose-mail-other-frame.
7180
7181 ** The `user-full-name' function now takes an optional parameter which
7182 can either be a number (the UID) or a string (the login name). The
7183 full name of the specified user will be returned.
7184
7185 ** Lisp packages that load files of customizations, or any other sort
7186 of user profile, should obey the variable init-file-user in deciding
7187 where to find it. They should load the profile of the user name found
7188 in that variable. If init-file-user is nil, meaning that the -q
7189 option was used, then Lisp packages should not load the customization
7190 files at all.
7191
7192 ** format-time-string now allows you to specify the field width
7193 and type of padding. This works as in printf: you write the field
7194 width as digits in the middle of a %-construct. If you start
7195 the field width with 0, it means to pad with zeros.
7196
7197 For example, %S normally specifies the number of seconds since the
7198 minute; %03S means to pad this with zeros to 3 positions, %_3S to pad
7199 with spaces to 3 positions. Plain %3S pads with zeros, because that
7200 is how %S normally pads to two positions.
7201
7202 ** thing-at-point now supports a new kind of "thing": url.
7203
7204 ** imenu.el changes.
7205
7206 You can now specify a function to be run when selecting an
7207 item from menu created by imenu.
7208
7209 An example of using this feature: if we define imenu items for the
7210 #include directives in a C file, we can open the included file when we
7211 select one of those items.
7212 \f
7213 * Emacs 19.34 is a bug-fix release with no user-visible changes.
7214 \f
7215 * Changes in Emacs 19.33.
7216
7217 ** Bibtex mode no longer turns on Auto Fill automatically. (No major
7218 mode should do that--it is the user's choice.)
7219
7220 ** The variable normal-auto-fill-function specifies the function to
7221 use for auto-fill-function, if and when Auto Fill is turned on.
7222 Major modes can set this locally to alter how Auto Fill works.
7223 \f
7224 * Editing Changes in Emacs 19.32
7225
7226 ** C-x f with no argument now signals an error.
7227 To set the fill column at the current column, use C-u C-x f.
7228
7229 ** Expanding dynamic abbrevs with M-/ is now smarter about case
7230 conversion. If you type the abbreviation with mixed case, and it
7231 matches the beginning of the expansion including case, then the
7232 expansion is copied verbatim. Using SPC M-/ to copy an additional
7233 word always copies it verbatim except when the previous copied word is
7234 all caps.
7235
7236 ** On a non-windowing terminal, which can display only one Emacs frame
7237 at a time, creating a new frame with C-x 5 2 also selects that frame.
7238
7239 When using a display that can show multiple frames at once, C-x 5 2
7240 does make the frame visible, but does not select it. This is the same
7241 as in previous Emacs versions.
7242
7243 ** You can use C-x 5 2 to create multiple frames on MSDOS, just as on a
7244 non-X terminal on Unix. Of course, only one frame is visible at any
7245 time, since your terminal doesn't have the ability to display multiple
7246 frames.
7247
7248 ** On Windows, set win32-pass-alt-to-system to a non-nil value
7249 if you would like tapping the Alt key to invoke the Windows menu.
7250 This feature is not enabled by default; since the Alt key is also the
7251 Meta key, it is too easy and painful to activate this feature by
7252 accident.
7253
7254 ** The command apply-macro-to-region-lines repeats the last defined
7255 keyboard macro once for each complete line within the current region.
7256 It does this line by line, by moving point to the beginning of that
7257 line and then executing the macro.
7258
7259 This command is not new, but was never documented before.
7260
7261 ** You can now use Mouse-1 to place the region around a string constant
7262 (something surrounded by doublequote characters or other delimiter
7263 characters of like syntax) by double-clicking on one of the delimiting
7264 characters.
7265
7266 ** Font Lock mode
7267
7268 *** Font Lock support modes
7269
7270 Font Lock can be configured to use Fast Lock mode and Lazy Lock mode (see
7271 below) in a flexible way. Rather than adding the appropriate function to the
7272 hook font-lock-mode-hook, you can use the new variable font-lock-support-mode
7273 to control which modes have Fast Lock mode or Lazy Lock mode turned on when
7274 Font Lock mode is enabled.
7275
7276 For example, to use Fast Lock mode when Font Lock mode is turned on, put:
7277
7278 (setq font-lock-support-mode 'fast-lock-mode)
7279
7280 in your ~/.emacs.
7281
7282 *** lazy-lock
7283
7284 The lazy-lock package speeds up Font Lock mode by making fontification occur
7285 only when necessary, such as when a previously unfontified part of the buffer
7286 becomes visible in a window. When you create a buffer with Font Lock mode and
7287 Lazy Lock mode turned on, the buffer is not fontified. When certain events
7288 occur (such as scrolling), Lazy Lock makes sure that the visible parts of the
7289 buffer are fontified. Lazy Lock also defers on-the-fly fontification until
7290 Emacs has been idle for a given amount of time.
7291
7292 To use this package, put in your ~/.emacs:
7293
7294 (setq font-lock-support-mode 'lazy-lock-mode)
7295
7296 To control the package behaviour, see the documentation for `lazy-lock-mode'.
7297
7298 ** Changes in BibTeX mode.
7299
7300 *** For all entries allow spaces and tabs between opening brace or
7301 paren and key.
7302
7303 *** Non-escaped double-quoted characters (as in `Sch"of') are now
7304 supported.
7305
7306 ** Gnus changes.
7307
7308 Gnus, the Emacs news reader, has undergone further rewriting. Many new
7309 commands and variables have been added. There should be no
7310 significant incompatibilities between this Gnus version and the
7311 previously released version, except in the message composition area.
7312
7313 Below is a list of the more user-visible changes. Coding changes
7314 between Gnus 5.1 and 5.2 are more extensive.
7315
7316 *** A new message composition mode is used. All old customization
7317 variables for mail-mode, rnews-reply-mode and gnus-msg are now
7318 obsolete.
7319
7320 *** Gnus is now able to generate "sparse" threads -- threads where
7321 missing articles are represented by empty nodes.
7322
7323 (setq gnus-build-sparse-threads 'some)
7324
7325 *** Outgoing articles are stored on a special archive server.
7326
7327 To disable this: (setq gnus-message-archive-group nil)
7328
7329 *** Partial thread regeneration now happens when articles are
7330 referred.
7331
7332 *** Gnus can make use of GroupLens predictions:
7333
7334 (setq gnus-use-grouplens t)
7335
7336 *** A trn-line tree buffer can be displayed.
7337
7338 (setq gnus-use-trees t)
7339
7340 *** An nn-like pick-and-read minor mode is available for the summary
7341 buffers.
7342
7343 (add-hook 'gnus-summary-mode-hook 'gnus-pick-mode)
7344
7345 *** In binary groups you can use a special binary minor mode:
7346
7347 `M-x gnus-binary-mode'
7348
7349 *** Groups can be grouped in a folding topic hierarchy.
7350
7351 (add-hook 'gnus-group-mode-hook 'gnus-topic-mode)
7352
7353 *** Gnus can re-send and bounce mail.
7354
7355 Use the `S D r' and `S D b'.
7356
7357 *** Groups can now have a score, and bubbling based on entry frequency
7358 is possible.
7359
7360 (add-hook 'gnus-summary-exit-hook 'gnus-summary-bubble-group)
7361
7362 *** Groups can be process-marked, and commands can be performed on
7363 groups of groups.
7364
7365 *** Caching is possible in virtual groups.
7366
7367 *** nndoc now understands all kinds of digests, mail boxes, rnews news
7368 batches, ClariNet briefs collections, and just about everything else.
7369
7370 *** Gnus has a new backend (nnsoup) to create/read SOUP packets.
7371
7372 *** The Gnus cache is much faster.
7373
7374 *** Groups can be sorted according to many criteria.
7375
7376 For instance: (setq gnus-group-sort-function 'gnus-group-sort-by-rank)
7377
7378 *** New group parameters have been introduced to set list-address and
7379 expiration times.
7380
7381 *** All formatting specs allow specifying faces to be used.
7382
7383 *** There are several more commands for setting/removing/acting on
7384 process marked articles on the `M P' submap.
7385
7386 *** The summary buffer can be limited to show parts of the available
7387 articles based on a wide range of criteria. These commands have been
7388 bound to keys on the `/' submap.
7389
7390 *** Articles can be made persistent -- as an alternative to saving
7391 articles with the `*' command.
7392
7393 *** All functions for hiding article elements are now toggles.
7394
7395 *** Article headers can be buttonized.
7396
7397 (add-hook 'gnus-article-display-hook 'gnus-article-add-buttons-to-head)
7398
7399 *** All mail backends support fetching articles by Message-ID.
7400
7401 *** Duplicate mail can now be treated properly. See the
7402 `nnmail-treat-duplicates' variable.
7403
7404 *** All summary mode commands are available directly from the article
7405 buffer.
7406
7407 *** Frames can be part of `gnus-buffer-configuration'.
7408
7409 *** Mail can be re-scanned by a daemonic process.
7410
7411 *** Gnus can make use of NoCeM files to filter spam.
7412
7413 (setq gnus-use-nocem t)
7414
7415 *** Groups can be made permanently visible.
7416
7417 (setq gnus-permanently-visible-groups "^nnml:")
7418
7419 *** Many new hooks have been introduced to make customizing easier.
7420
7421 *** Gnus respects the Mail-Copies-To header.
7422
7423 *** Threads can be gathered by looking at the References header.
7424
7425 (setq gnus-summary-thread-gathering-function
7426 'gnus-gather-threads-by-references)
7427
7428 *** Read articles can be stored in a special backlog buffer to avoid
7429 refetching.
7430
7431 (setq gnus-keep-backlog 50)
7432
7433 *** A clean copy of the current article is always stored in a separate
7434 buffer to allow easier treatment.
7435
7436 *** Gnus can suggest where to save articles. See `gnus-split-methods'.
7437
7438 *** Gnus doesn't have to do as much prompting when saving.
7439
7440 (setq gnus-prompt-before-saving t)
7441
7442 *** gnus-uu can view decoded files asynchronously while fetching
7443 articles.
7444
7445 (setq gnus-uu-grabbed-file-functions 'gnus-uu-grab-view)
7446
7447 *** Filling in the article buffer now works properly on cited text.
7448
7449 *** Hiding cited text adds buttons to toggle hiding, and how much
7450 cited text to hide is now customizable.
7451
7452 (setq gnus-cited-lines-visible 2)
7453
7454 *** Boring headers can be hidden.
7455
7456 (add-hook 'gnus-article-display-hook 'gnus-article-hide-boring-headers)
7457
7458 *** Default scoring values can now be set from the menu bar.
7459
7460 *** Further syntax checking of outgoing articles have been added.
7461
7462 The Gnus manual has been expanded. It explains all these new features
7463 in greater detail.
7464 \f
7465 * Lisp Changes in Emacs 19.32
7466
7467 ** The function set-visited-file-name now accepts an optional
7468 second argument NO-QUERY. If it is non-nil, then the user is not
7469 asked for confirmation in the case where the specified file already
7470 exists.
7471
7472 ** The variable print-length applies to printing vectors and bitvectors,
7473 as well as lists.
7474
7475 ** The new function keymap-parent returns the parent keymap
7476 of a given keymap.
7477
7478 ** The new function set-keymap-parent specifies a new parent for a
7479 given keymap. The arguments are KEYMAP and PARENT. PARENT must be a
7480 keymap or nil.
7481
7482 ** Sometimes menu keymaps use a command name, a symbol, which is really
7483 an automatically generated alias for some other command, the "real"
7484 name. In such a case, you should give that alias symbol a non-nil
7485 menu-alias property. That property tells the menu system to look for
7486 equivalent keys for the real name instead of equivalent keys for the
7487 alias.
7488 \f
7489 * Editing Changes in Emacs 19.31
7490
7491 ** Freedom of the press restricted in the United States.
7492
7493 Emacs has been censored in accord with the Communications Decency Act.
7494 This includes removing some features of the doctor program. That law
7495 was described by its supporters as a ban on pornography, but it bans
7496 far more than that. The Emacs distribution has never contained any
7497 pornography, but parts of it were nonetheless prohibited.
7498
7499 For information on US government censorship of the Internet, and what
7500 you can do to bring back freedom of the press, see the web site
7501 `http://www.vtw.org/'.
7502
7503 ** A note about C mode indentation customization.
7504
7505 The old (Emacs 19.29) ways of specifying a C indentation style
7506 do not normally work in the new implementation of C mode.
7507 It has its own methods of customizing indentation, which are
7508 much more powerful than the old C mode. See the Editing Programs
7509 chapter of the manual for details.
7510
7511 However, you can load the library cc-compat to make the old
7512 customization variables take effect.
7513
7514 ** Marking with the mouse.
7515
7516 When you mark a region with the mouse, the region now remains
7517 highlighted until the next input event, regardless of whether you are
7518 using M-x transient-mark-mode.
7519
7520 ** Improved Windows NT/95 support.
7521
7522 *** Emacs now supports scroll bars on Windows NT and Windows 95.
7523
7524 *** Emacs now supports subprocesses on Windows 95. (Subprocesses used
7525 to work on NT only and not on 95.)
7526
7527 *** There are difficulties with subprocesses, though, due to problems
7528 in Windows, beyond the control of Emacs. They work fine as long as
7529 you run Windows applications. The problems arise when you run a DOS
7530 application in a subprocesses. Since current shells run as DOS
7531 applications, these problems are significant.
7532
7533 If you run a DOS application in a subprocess, then the application is
7534 likely to busy-wait, which means that your machine will be 100% busy.
7535 However, if you don't mind the temporary heavy load, the subprocess
7536 will work OK as long as you tell it to terminate before you start any
7537 other DOS application as a subprocess.
7538
7539 Emacs is unable to terminate or interrupt a DOS subprocess.
7540 You have to do this by providing input directly to the subprocess.
7541
7542 If you run two DOS applications at the same time in two separate
7543 subprocesses, even if one of them is asynchronous, you will probably
7544 have to reboot your machine--until then, it will remain 100% busy.
7545 Windows simply does not cope when one Windows process tries to run two
7546 separate DOS subprocesses. Typing CTL-ALT-DEL and then choosing
7547 Shutdown seems to work although it may take a few minutes.
7548
7549 ** M-x resize-minibuffer-mode.
7550
7551 This command, not previously mentioned in NEWS, toggles a mode in
7552 which the minibuffer window expands to show as many lines as the
7553 minibuffer contains.
7554
7555 ** `title' frame parameter and resource.
7556
7557 The `title' X resource now specifies just the frame title, nothing else.
7558 It does not affect the name used for looking up other X resources.
7559 It works by setting the new `title' frame parameter, which likewise
7560 affects just the displayed title of the frame.
7561
7562 The `name' parameter continues to do what it used to do:
7563 it specifies the frame name for looking up X resources,
7564 and also serves as the default for the displayed title
7565 when the `title' parameter is unspecified or nil.
7566
7567 ** Emacs now uses the X toolkit by default, if you have a new
7568 enough version of X installed (X11R5 or newer).
7569
7570 ** When you compile Emacs with the Motif widget set, Motif handles the
7571 F10 key by activating the menu bar. To avoid confusion, the usual
7572 Emacs binding of F10 is replaced with a no-op when using Motif.
7573
7574 If you want to be able to use F10 in Emacs, you can rebind the Motif
7575 menubar to some other key which you don't use. To do so, add
7576 something like this to your X resources file. This example rebinds
7577 the Motif menu bar activation key to S-F12:
7578
7579 Emacs*defaultVirtualBindings: osfMenuBar : Shift<Key>F12
7580
7581 ** In overwrite mode, DEL now inserts spaces in most cases
7582 to replace the characters it "deletes".
7583
7584 ** The Rmail summary now shows the number of lines in each message.
7585
7586 ** Rmail has a new command M-x unforward-rmail-message, which extracts
7587 a forwarded message from the message that forwarded it. To use it,
7588 select a message which contains a forwarded message and then type the command.
7589 It inserts the forwarded message as a separate Rmail message
7590 immediately after the selected one.
7591
7592 This command also undoes the textual modifications that are standardly
7593 made, as part of forwarding, by Rmail and other mail reader programs.
7594
7595 ** Turning off saving of .saves-... files in your home directory.
7596
7597 Each Emacs session writes a file named .saves-... in your home
7598 directory to record which files M-x recover-session should recover.
7599 If you exit Emacs normally with C-x C-c, it deletes that file. If
7600 Emacs or the operating system crashes, the file remains for M-x
7601 recover-session.
7602
7603 You can turn off the writing of these files by setting
7604 auto-save-list-file-name to nil. If you do this, M-x recover-session
7605 will not work.
7606
7607 Some previous Emacs versions failed to delete these files even on
7608 normal exit. This is fixed now. If you are thinking of turning off
7609 this feature because of past experiences with versions that had this
7610 bug, it would make sense to check whether you still want to do so
7611 now that the bug is fixed.
7612
7613 ** Changes to Version Control (VC)
7614
7615 There is a new variable, vc-follow-symlinks. It indicates what to do
7616 when you visit a link to a file that is under version control.
7617 Editing the file through the link bypasses the version control system,
7618 which is dangerous and probably not what you want.
7619
7620 If this variable is t, VC follows the link and visits the real file,
7621 telling you about it in the echo area. If it is `ask' (the default),
7622 VC asks for confirmation whether it should follow the link. If nil,
7623 the link is visited and a warning displayed.
7624
7625 ** iso-acc.el now lets you specify a choice of language.
7626 Languages include "latin-1" (the default) and "latin-2" (which
7627 is designed for entering ISO Latin-2 characters).
7628
7629 There are also choices for specific human languages such as French and
7630 Portuguese. These are subsets of Latin-1, which differ in that they
7631 enable only the accent characters needed for particular language.
7632 The other accent characters, not needed for the chosen language,
7633 remain normal.
7634
7635 ** Posting articles and sending mail now has M-TAB completion on various
7636 header fields (Newsgroups, To, CC, ...).
7637
7638 Completion in the Newsgroups header depends on the list of groups
7639 known to your news reader. Completion in the Followup-To header
7640 offers those groups which are in the Newsgroups header, since
7641 Followup-To usually just holds one of those.
7642
7643 Completion in fields that hold mail addresses works based on the list
7644 of local users plus your aliases. Additionally, if your site provides
7645 a mail directory or a specific host to use for any unrecognized user
7646 name, you can arrange to query that host for completion also. (See the
7647 documentation of variables `mail-directory-process' and
7648 `mail-directory-stream'.)
7649
7650 ** A greatly extended sgml-mode offers new features such as (to be configured)
7651 skeletons with completing read for tags and attributes, typing named
7652 characters including optionally all 8bit characters, making tags invisible
7653 with optional alternate display text, skipping and deleting tag(pair)s.
7654
7655 Note: since Emacs' syntax feature cannot limit the special meaning of ', " and
7656 - to inside <>, for some texts the result, especially of font locking, may be
7657 wrong (see `sgml-specials' if you get wrong results).
7658
7659 The derived html-mode configures this with tags and attributes more or
7660 less HTML3ish. It also offers optional quick keys like C-c 1 for
7661 headline or C-c u for unordered list (see `html-quick-keys'). Edit /
7662 Text Properties / Face or M-g combinations create tags as applicable.
7663 Outline minor mode is supported and level 1 font-locking tries to
7664 fontify tag contents (which only works when they fit on one line, due
7665 to a limitation in font-lock).
7666
7667 External viewing via browse-url can occur automatically upon saving.
7668
7669 ** M-x imenu-add-to-menubar now adds to the menu bar for the current
7670 buffer only. If you want to put an Imenu item in the menu bar for all
7671 buffers that use a particular major mode, use the mode hook, as in
7672 this example:
7673
7674 (add-hook 'emacs-lisp-mode-hook
7675 '(lambda () (imenu-add-to-menubar "Index")))
7676
7677 ** Changes in BibTeX mode.
7678
7679 *** Field names may now contain digits, hyphens, and underscores.
7680
7681 *** Font Lock mode is now supported.
7682
7683 *** bibtex-make-optional-field is no longer interactive.
7684
7685 *** If bibtex-maintain-sorted-entries is non-nil, inserting new
7686 entries is now done with a faster algorithm. However, inserting
7687 will fail in this case if the buffer contains invalid entries or
7688 isn't in sorted order, so you should finish each entry with C-c C-c
7689 (bibtex-close-entry) after you have inserted or modified it.
7690 The default value of bibtex-maintain-sorted-entries is nil.
7691
7692 *** Function `show-all' is no longer bound to a key, since C-u C-c C-q
7693 does the same job.
7694
7695 *** Entries with quotes inside quote-delimited fields (as `author =
7696 "Stefan Sch{\"o}f"') are now supported.
7697
7698 *** Case in field names doesn't matter anymore when searching for help
7699 text.
7700
7701 ** Font Lock mode
7702
7703 *** Global Font Lock mode
7704
7705 Font Lock mode can be turned on globally, in buffers that support it, by the
7706 new command global-font-lock-mode. You can use the new variable
7707 font-lock-global-modes to control which modes have Font Lock mode automagically
7708 turned on. By default, this variable is set so that Font Lock mode is turned
7709 on globally where the buffer mode supports it.
7710
7711 For example, to automagically turn on Font Lock mode where supported, put:
7712
7713 (global-font-lock-mode t)
7714
7715 in your ~/.emacs.
7716
7717 *** Local Refontification
7718
7719 In Font Lock mode, editing a line automatically refontifies that line only.
7720 However, if your change alters the syntactic context for following lines,
7721 those lines remain incorrectly fontified. To refontify them, use the new
7722 command M-g M-g (font-lock-fontify-block).
7723
7724 In certain major modes, M-g M-g refontifies the entire current function.
7725 (The variable font-lock-mark-block-function controls how to find the
7726 current function.) In other major modes, M-g M-g refontifies 16 lines
7727 above and below point.
7728
7729 With a prefix argument N, M-g M-g refontifies N lines above and below point.
7730
7731 ** Follow mode
7732
7733 Follow mode is a new minor mode combining windows showing the same
7734 buffer into one tall "virtual window". The windows are typically two
7735 side-by-side windows. Follow mode makes them scroll together as if
7736 they were a unit. To use it, go to a frame with just one window,
7737 split it into two side-by-side windows using C-x 3, and then type M-x
7738 follow-mode.
7739
7740 M-x follow-mode turns off Follow mode if it is already enabled.
7741
7742 To display two side-by-side windows and activate Follow mode, use the
7743 command M-x follow-delete-other-windows-and-split.
7744
7745 ** hide-show changes.
7746
7747 The hooks hs-hide-hooks and hs-show-hooks have been renamed
7748 to hs-hide-hook and hs-show-hook, to follow the convention for
7749 normal hooks.
7750
7751 ** Simula mode now has a menu containing the most important commands.
7752 The new command simula-indent-exp is bound to C-M-q.
7753
7754 ** etags can now handle programs written in Erlang. Files are
7755 recognised by the extensions .erl and .hrl. The tagged lines are
7756 those that begin a function, record, or macro.
7757
7758 ** MSDOS Changes
7759
7760 *** It is now possible to compile Emacs with the version 2 of DJGPP.
7761 Compilation with DJGPP version 1 also still works.
7762
7763 *** The documentation of DOS-specific aspects of Emacs was rewritten
7764 and expanded; see the ``MS-DOS'' node in the on-line docs.
7765
7766 *** Emacs now uses ~ for backup file names, not .bak.
7767
7768 *** You can simulate mouse-3 on two-button mice by simultaneously
7769 pressing both mouse buttons.
7770
7771 *** A number of packages and commands which previously failed or had
7772 restricted functionality on MS-DOS, now work. The most important ones
7773 are:
7774
7775 **** Printing (both with `M-x lpr-buffer' and with `ps-print' package)
7776 now works.
7777
7778 **** `Ediff' works (in a single-frame mode).
7779
7780 **** `M-x display-time' can be used on MS-DOS (due to the new
7781 implementation of Emacs timers, see below).
7782
7783 **** `Dired' supports Unix-style shell wildcards.
7784
7785 **** The `c-macro-expand' command now works as on other platforms.
7786
7787 **** `M-x recover-session' works.
7788
7789 **** `M-x list-colors-display' displays all the available colors.
7790
7791 **** The `TPU-EDT' package works.
7792 \f
7793 * Lisp changes in Emacs 19.31.
7794
7795 ** The function using-unix-filesystems on Windows NT and Windows 95
7796 tells Emacs to read and write files assuming that they reside on a
7797 remote Unix filesystem. No CR/LF translation is done on any files in
7798 this case. Invoking using-unix-filesystems with t activates this
7799 behavior, and invoking it with any other value deactivates it.
7800
7801 ** Change in system-type and system-configuration values.
7802
7803 The value of system-type on a Linux-based GNU system is now `lignux',
7804 not `linux'. This means that some programs which use `system-type'
7805 need to be changed. The value of `system-configuration' will also
7806 be different.
7807
7808 It is generally recommended to use `system-configuration' rather
7809 than `system-type'.
7810
7811 See the file LINUX-GNU in this directory for more about this.
7812
7813 ** The functions shell-command and dired-call-process
7814 now run file name handlers for default-directory, if it has them.
7815
7816 ** Undoing the deletion of text now restores the positions of markers
7817 that pointed into or next to the deleted text.
7818
7819 ** Timers created with run-at-time now work internally to Emacs, and
7820 no longer use a separate process. Therefore, they now work more
7821 reliably and can be used for shorter time delays.
7822
7823 The new function run-with-timer is a convenient way to set up a timer
7824 to run a specified amount of time after the present. A call looks
7825 like this:
7826
7827 (run-with-timer SECS REPEAT FUNCTION ARGS...)
7828
7829 SECS says how many seconds should elapse before the timer happens.
7830 It may be an integer or a floating point number. When the timer
7831 becomes ripe, the action is to call FUNCTION with arguments ARGS.
7832
7833 REPEAT gives the interval for repeating the timer (measured in
7834 seconds). It may be an integer or a floating point number. nil or 0
7835 means don't repeat at all--call FUNCTION just once.
7836
7837 *** with-timeout provides an easy way to do something but give
7838 up if too much time passes.
7839
7840 (with-timeout (SECONDS TIMEOUT-FORMS...) BODY...)
7841
7842 This executes BODY, but gives up after SECONDS seconds.
7843 If it gives up, it runs the TIMEOUT-FORMS and returns the value
7844 of the last one of them. Normally it returns the value of the last
7845 form in BODY.
7846
7847 *** You can now arrange to call a function whenever Emacs is idle for
7848 a certain length of time. To do this, call run-with-idle-timer. A
7849 call looks like this:
7850
7851 (run-with-idle-timer SECS REPEAT FUNCTION ARGS...)
7852
7853 SECS says how many seconds of idleness should elapse before the timer
7854 runs. It may be an integer or a floating point number. When the
7855 timer becomes ripe, the action is to call FUNCTION with arguments
7856 ARGS.
7857
7858 Emacs becomes idle whenever it finishes executing a keyboard or mouse
7859 command. It remains idle until it receives another keyboard or mouse
7860 command.
7861
7862 REPEAT, if non-nil, means this timer should be activated again each
7863 time Emacs becomes idle and remains idle for SECS seconds The timer
7864 does not repeat if Emacs *remains* idle; it runs at most once after
7865 each time Emacs becomes idle.
7866
7867 If REPEAT is nil, the timer runs just once, the first time Emacs is
7868 idle for SECS seconds.
7869
7870 *** post-command-idle-hook is now obsolete; you shouldn't use it at
7871 all, because it interferes with the idle timer mechanism. If your
7872 programs use post-command-idle-hook, convert them to use idle timers
7873 instead.
7874
7875 *** y-or-n-p-with-timeout lets you ask a question but give up if
7876 there is no answer within a certain time.
7877
7878 (y-or-n-p-with-timeout PROMPT SECONDS DEFAULT-VALUE)
7879
7880 asks the question PROMPT (just like y-or-n-p). If the user answers
7881 within SECONDS seconds, it returns the answer that the user gave.
7882 Otherwise it gives up after SECONDS seconds, and returns DEFAULT-VALUE.
7883
7884 ** Minor change to `encode-time': you can now pass more than seven
7885 arguments. If you do that, the first six arguments have the usual
7886 meaning, the last argument is interpreted as the time zone, and the
7887 arguments in between are ignored.
7888
7889 This means that it works to use the list returned by `decode-time' as
7890 the list of arguments for `encode-time'.
7891
7892 ** The default value of load-path now includes the directory
7893 /usr/local/share/emacs/VERSION/site-lisp In addition to
7894 /usr/local/share/emacs/site-lisp. You can use this new directory for
7895 site-specific Lisp packages that belong with a particular Emacs
7896 version.
7897
7898 It is not unusual for a Lisp package that works well in one Emacs
7899 version to cause trouble in another. Sometimes packages need updating
7900 for incompatible changes; sometimes they look at internal data that
7901 has changed; sometimes the package has been installed in Emacs itself
7902 and the installed version should be used. Whatever the reason for the
7903 problem, this new feature makes it easier to solve.
7904
7905 ** When your program contains a fixed file name (like .completions or
7906 .abbrev.defs), the file name usually needs to be different on operating
7907 systems with limited file name syntax.
7908
7909 Now you can avoid ad-hoc conditionals by using the function
7910 convert-standard-filename to convert the file name to a proper form
7911 for each operating system. Here is an example of use, from the file
7912 completions.el:
7913
7914 (defvar save-completions-file-name
7915 (convert-standard-filename "~/.completions")
7916 "*The filename to save completions to.")
7917
7918 This sets the variable save-completions-file-name to a value that
7919 depends on the operating system, because the definition of
7920 convert-standard-filename depends on the operating system. On
7921 Unix-like systems, it returns the specified file name unchanged. On
7922 MS-DOS, it adapts the name to fit the limitations of that system.
7923
7924 ** The interactive spec N now returns the numeric prefix argument
7925 rather than the raw prefix argument. (It still reads a number using the
7926 minibuffer if there is no prefix argument at all.)
7927
7928 ** When a process is deleted, this no longer disconnects the process
7929 marker from its buffer position.
7930
7931 ** The variable garbage-collection-messages now controls whether
7932 Emacs displays a message at the beginning and end of garbage collection.
7933 The default is nil, meaning there are no messages.
7934
7935 ** The variable debug-ignored-errors specifies certain kinds of errors
7936 that should not enter the debugger. Its value is a list of error
7937 condition symbols and/or regular expressions. If the error has any
7938 of the condition symbols listed, or if any of the regular expressions
7939 matches the error message, then that error does not enter the debugger,
7940 regardless of the value of debug-on-error.
7941
7942 This variable is initialized to match certain common but uninteresting
7943 errors that happen often during editing.
7944
7945 ** The new function error-message-string converts an error datum
7946 into its error message. The error datum is what condition-case
7947 puts into the variable, to describe the error that happened.
7948
7949 ** Anything that changes which buffer appears in a given window
7950 now runs the window-scroll-functions for that window.
7951
7952 ** The new function get-buffer-window-list returns a list of windows displaying
7953 a buffer. The function is called with the buffer (a buffer object or a buffer
7954 name) and two optional arguments specifying the minibuffer windows and frames
7955 to search. Therefore this function takes optional args like next-window etc.,
7956 and not get-buffer-window.
7957
7958 ** buffer-substring now runs the hook buffer-access-fontify-functions,
7959 calling each function with two arguments--the range of the buffer
7960 being accessed. buffer-substring-no-properties does not call them.
7961
7962 If you use this feature, you should set the variable
7963 buffer-access-fontified-property to a non-nil symbol, which is a
7964 property name. Then, if all the characters in the buffer range have a
7965 non-nil value for that property, the buffer-access-fontify-functions
7966 are not called. When called, these functions should put a non-nil
7967 property on the text that they fontify, so that they won't get called
7968 over and over for the same text.
7969
7970 ** Changes in lisp-mnt.el
7971
7972 *** The lisp-mnt package can now recognize file headers that are written
7973 in the formats used by the `what' command and the RCS `ident' command:
7974
7975 ;; @(#) HEADER: text
7976 ;; $HEADER: text $
7977
7978 in addition to the normal
7979
7980 ;; HEADER: text
7981
7982 *** The commands lm-verify and lm-synopsis are now interactive. lm-verify
7983 checks that the library file has proper sections and headers, and
7984 lm-synopsis extracts first line "synopsis'"information.
7985 \f
7986 * For older news, see the file ONEWS.
7987
7988 ----------------------------------------------------------------------
7989 Copyright information:
7990
7991 Copyright (C) 1996, 1997, 1998, 1999, 2000 Free Software Foundation, Inc.
7992
7993 Permission is granted to anyone to make or distribute verbatim copies
7994 of this document as received, in any medium, provided that the
7995 copyright notice and this permission notice are preserved,
7996 thus giving the recipient permission to redistribute in turn.
7997
7998 Permission is granted to distribute modified versions
7999 of this document, or of portions of it,
8000 under the above conditions, provided also that they
8001 carry prominent notices stating who last changed them.
8002 \f
8003 Local variables:
8004 mode: outline
8005 paragraph-separate: "[ \f]*$"
8006 end: