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1 GNU Emacs NEWS -- history of user-visible changes. 2000-09-27
2 Copyright (C) 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 ** Support for GNU/Linux on IA64 machines has been added.
12
13 ** Support for LynxOS has been added.
14
15 ** `movemail' defaults to supporting POP. You can turn this off using
16 the --without-pop configure option, should that be necessary.
17
18 ** There are new configure options associated with the support for
19 images and toolkit scrollbars. Use the --help option in `configure'
20 to list them.
21
22 ** There is a new configure option `--without-xim' that instructs
23 Emacs to not use X Input Methods (XIM), if these are available.
24
25 ** There is a new configure option `--disable-largefile' to omit
26 Unix-98-style support for large files if that is available.
27
28 ** You can build a 64-bit Emacs for SPARC/Solaris systems which
29 support 64-bit executables and also on Irix 6.5. This increases the
30 maximum buffer size. See etc/MACHINES for instructions.
31
32 \f
33 * Changes in Emacs 21.1
34
35 ** The new global minor mode `auto-image-file-mode' allows image files
36 to be visited as images.
37
38 ** The functions `keep-lines', `flush-lines' and `how-many' now
39 operate on the active region in Transient Mark mode.
40
41 ** The header line in an Info buffer is now displayed as an emacs header-line
42 (which is like a mode-line, but at the top of the window), so that it
43 remains visible even when the buffer has been scrolled. This behavior
44 may be disabled by customizing the option `Info-use-header-line'.
45
46 ** `gnus-user-agent' is a new possibility for `mail-user-agent'. It
47 is like `message-user-agent', but with all the Gnus paraphernalia.
48
49 +++
50 ** The recommended way of using Iswitchb is via the new global minor
51 mode `iswitchb-mode'.
52
53 ** Gnus changes.
54
55 The Gnus NEWS entries are short, but they reflect sweeping changes in
56 four areas: Article display treatment, MIME treatment,
57 internationalization and mail-fetching.
58
59 *** The mail-fetching functions have changed. See the manual for the
60 many details. In particular, all procmail fetching variables are gone.
61
62 If you used procmail like in
63
64 (setq nnmail-use-procmail t)
65 (setq nnmail-spool-file 'procmail)
66 (setq nnmail-procmail-directory "~/mail/incoming/")
67 (setq nnmail-procmail-suffix "\\.in")
68
69 this now has changed to
70
71 (setq mail-sources
72 '((directory :path "~/mail/incoming/"
73 :suffix ".in")))
74
75 More information is available in the info doc at Select Methods ->
76 Getting Mail -> Mail Sources
77
78 *** Gnus is now a MIME-capable reader. This affects many parts of
79 Gnus, and adds a slew of new commands. See the manual for details.
80
81 *** Gnus has also been multilingualized. This also affects too many
82 parts of Gnus to summarize here, and adds many new variables.
83 Separate MIME packages like SEMI will not work. There are built-in
84 facilities equivalent to those of gnus-mule.el, which is now just a
85 compatibility layer.
86
87 *** gnus-auto-select-first can now be a function to be
88 called to position point.
89
90 *** The user can now decide which extra headers should be included in
91 summary buffers and NOV files.
92
93 *** `gnus-article-display-hook' has been removed. Instead, a number
94 of variables starting with `gnus-treat-' have been added.
95
96 *** The Gnus posting styles have been redone again and now work in a
97 subtly different manner.
98
99 *** New web-based backends have been added: nnslashdot, nnwarchive
100 and nnultimate. nnweb has been revamped, again, to keep up with
101 ever-changing layouts.
102
103 *** Gnus can now read IMAP mail via nnimap.
104
105 *** There is image support.
106
107 ** When your terminal can't display characters from some of the ISO
108 8859 character sets but can display Latin-1, you can display
109 more-or-less mnemonic sequences of ASCII/Latin-1 characters instead of
110 empty boxes (under a window system) or question marks (not under a
111 window system). Customize the option `latin1-display' to turn this
112 on.
113
114 ** The new user-option `find-file-suppress-same-file-warnings' can be
115 set to suppress warnings ``X and Y are the same file'' when visiting a
116 file that is already visited under a different name.
117
118 ** The new user-option `electric-help-shrink-window' can be set to
119 nil to prevent adjusting the help window size to the buffer size.
120
121 ** Emacs now checks for recursive loads of Lisp files. If the
122 recursion depth exceeds `recursive-load-depth-limit', an error is
123 signaled.
124
125 ** The Strokes package has been updated. If your Emacs has XPM
126 support, you can use it for pictographic editing. In Strokes mode,
127 use C-mouse-2 to compose a complex stoke and insert it into the
128 buffer. You can encode or decode a strokes buffer with new commands
129 M-x strokes-encode-buffer and M-x strokes-decode-buffer. There is a
130 new command M-x strokes-list-strokes.
131
132 +++
133 ** New command M-x describe-character-set reads a character set name
134 and displays information about that.
135
136 ** When an error is signaled during the loading of the user's init
137 file, Emacs now pops up the *Messages* buffer.
138
139 ** Polish and German translations of Emacs' reference card have been
140 added. They are named `pl-refcard.tex' and `de-refcard.tex'.
141 Postscript files are included.
142
143 ** A reference card for Dired has been added. Its name is
144 `dired-ref.tex'.
145
146 ** The new variable `auto-mode-interpreter-regexp' contains a regular
147 expression matching interpreters, for file mode determination.
148
149 This regular expression is matched against the first line of a file to
150 determine the file's mode in `set-auto-mode' when Emacs can't deduce a
151 mode from the file's name. If it matches, the file is assumed to be
152 interpreted by the interpreter matched by the second group of the
153 regular expression. The mode is then determined as the mode
154 associated with that interpreter in `interpreter-mode-alist'.
155
156 ** C-down-mouse-3 is bound differently. Now if the menu bar is not
157 displayed it pops up a menu containing the items which would be on the
158 menu bar. If the menu bar is displayed, it pops up the major mode
159 menu or the Edit menu if there is no major mode menu.
160
161 ** Variable `load-path' is no longer customizable because it contains
162 a version-dependent component.
163
164 ** The <delete> function key is now bound to `delete-char' by default.
165 Note that this takes effect only on window systems. On TTYs, Emacs
166 will receive ASCII 127 when the DEL key is pressed. This
167 character is still bound as before.
168
169 ** Item Save Options on the Options menu allows saving options set
170 using that menu.
171
172 ** New function executable-make-buffer-file-executable-if-script-p is
173 suitable as an after-save-hook as an alternative to `executable-chmod'.
174
175 +++
176 ** The most preferred coding-system is now used to save a buffer if
177 buffer-file-coding-system is `undecided' and it is safe for the buffer
178 contents. (The most preferred is set by set-language-environment or
179 by M-x prefer-coding-system.) Thus if you visit an ASCII file and
180 insert a non-ASCII character from your current language environment,
181 the file will be saved silently with the appropriate coding.
182 Previously you would be prompted for a safe coding system.
183
184 +++
185 ** New variable `inhibit-iso-escape-detection' determines if Emacs'
186 coding system detection algorithm should pay attention to ISO2022's
187 escape sequences. If this variable is non-nil, the algorithm ignores
188 such escape sequences. The default value is nil, and it is
189 recommended not to change it except for the special case that you
190 always want to read any escape code verbatim. If you just want to
191 read a specific file without decoding escape codes, use C-x RET c
192 (`universal-coding-system-argument'). For instance, C-x RET c latin-1
193 RET C-x C-f filename RET.
194
195 ** Variable `default-korean-keyboard' is initialized properly from the
196 environment variable `HANGUL_KEYBOARD_TYPE'.
197
198 +++
199 ** C-u C-x = provides detailed information about the character at
200 point in a pop-up window.
201
202 +++
203 ** New command M-x list-charset-chars reads a character set name and
204 displays all characters in that character set.
205
206 ** M-x set-terminal-coding-system (C-x RET t) now allows CCL-based
207 coding systems such as cpXXX and cyrillic-koi8.
208
209 +++
210 ** M-; now calls comment-dwim which tries to do something clever based
211 on the context. M-x kill-comment is now an alias to comment-kill,
212 defined on newcomment.el.
213
214 +++
215 ** The function `getenv' is now callable interactively.
216
217 ** The many obsolete language `setup-...-environment' commands have
218 been removed -- use `set-language-environment'.
219
220 +++
221 ** New user options `display-time-mail-face' and
222 `display-time-use-mail-icon' control the appearance of mode-line mail
223 indicator used by the display-time package. On a suitable display the
224 indicator can be an icon and is mouse-sensitive.
225
226 +++
227 ** Emacs' auto-save list files are now by default stored in a
228 sub-directory `.emacs.d/auto-save-list/' of the user's home directory.
229 (On MS-DOS, this subdirectory's name is `_emacs.d/auto-save.list/'.)
230 You can customize `auto-save-list-prefix' to change this location.
231
232 +++
233 ** On window-systems, additional space can be put between text lines
234 on the display using several methods
235
236 +++
237 - By setting frame parameter `line-spacing' to PIXELS. PIXELS must be
238 a positive integer, and specifies that PIXELS number of pixels should
239 be put below text lines on the affected frame or frames.
240
241 +++
242 - By setting X resource `lineSpacing', class `LineSpacing'. This is
243 equivalent ot specifying the frame parameter.
244
245 - By specifying `--line-spacing=N' or `-lsp N' on the command line.
246
247 - By setting buffer-local variable `line-spacing'. The meaning is
248 the same, but applies to the a particular buffer only.
249
250 +++
251 ** The new command `clone-indirect-buffer' can be used to create
252 an indirect buffer that is a twin copy of the current buffer. The
253 command `clone-indirect-buffer-other-window', bound to C-x 4 c,
254 does the same but displays the indirect buffer in another window.
255
256 +++
257 ** New user options `backup-directory-alist' and
258 `make-backup-file-name-function' control the placement of backups,
259 typically in a single directory or in an invisible sub-directory.
260
261 ** New commands iso-iso2sgml and iso-sgml2iso convert between Latin-1
262 characters and the corresponding SGML (HTML) entities.
263
264 +++
265 ** Emacs now refuses to load compiled Lisp files which weren't
266 compiled with Emacs. Set `load-dangerous-libraries' to t to change
267 this behavior.
268
269 The reason for this change is an incompatible change in XEmacs' byte
270 compiler. Files compiled with XEmacs can contain byte codes that let
271 Emacs dump core.
272
273 +++
274 ** New X resources recognized
275
276 *** The X resource `synchronous', class `Synchronous', specifies
277 whether Emacs should run in synchronous mode. Synchronous mode
278 is useful for debugging X problems.
279
280 Example:
281
282 emacs.synchronous: true
283
284 *** The X resource `visualClass, class `VisualClass', specifies the
285 visual Emacs should use. The resource's value should be a string of
286 the form `CLASS-DEPTH', where CLASS is the name of the visual class,
287 and DEPTH is the requested color depth as a decimal number. Valid
288 visual class names are
289
290 TrueColor
291 PseudoColor
292 DirectColor
293 StaticColor
294 GrayScale
295 StaticGray
296
297 Visual class names specified as X resource are case-insensitive, i.e.
298 `pseudocolor', `Pseudocolor' and `PseudoColor' all have the same
299 meaning.
300
301 The program `xdpyinfo' can be used to list the visual classes
302 supported on your display, and which depths they have. If
303 `visualClass' is not specified, Emacs uses the display's default
304 visual.
305
306 Example:
307
308 emacs.visualClass: TrueColor-8
309
310 *** The X resource `privateColormap', class `PrivateColormap',
311 specifies that Emacs should use a private colormap if it is using the
312 default visual, and that visual is of class PseudoColor. Recognized
313 resource values are `true' or `on'.
314
315 Example:
316
317 emacs.privateColormap: true
318
319 ** The menu bar configuration has changed. The new configuration is
320 more CUA-compliant. The most significant change is that Options is
321 now a separate menu-bar item, with Mule and Customize as its submenus.
322
323 ** User-option `show-cursor-in-non-selected-windows' controls how to
324 display the cursor in non-selected windows. If nil, no cursor is
325 shown, if non-nil a hollow box cursor is shown. This option can
326 be customized.
327
328 +++
329 ** The variable `echo-keystrokes' may now have a floating point value.
330
331 +++
332 ** C-x 5 1 runs the new command delete-other-frames which deletes
333 all frames except the selected one.
334
335 ** If your init file is compiled (.emacs.elc), `user-init-file' is set
336 to the source name (.emacs.el), if that exists, after loading it.
337
338 ** The help string specified for a menu-item whose definition contains
339 the property `:help HELP' is now displayed under X, on MS-Windows, and
340 MS-DOS, either in the echo area or with tooltips. Many standard menus
341 displayed by Emacs now have help strings.
342
343 +++
344 ** Highlighting of mouse-sensitive regions is now supported in the
345 MS-DOS version of Emacs.
346
347 ** New user option `read-mail-command' specifies a command to use to
348 read mail from the menu etc.
349
350 +++
351 ** Hexl contains a new command `hexl-insert-hex-string' which inserts
352 a string of hexadecimal numbers read from the mini-buffer.
353
354 ** Changes in Texinfo mode.
355
356 ** A couple of new key bindings have been added for inserting Texinfo
357 macros
358
359 Key binding Macro
360 -------------------------
361 C-c C-c C-s @strong
362 C-c C-c C-e @emph
363 C-c C-c u @url
364 C-c C-c q @quotation
365 C-c C-c m @email
366
367 ** Changes in Outline mode.
368
369 There is now support for Imenu to index headings. A new command
370 `outline-headers-as-kill' copies the visible headings in the region to
371 the kill ring, e.g. to produce a table of contents.
372
373 ** Changes to Emacs Server
374
375 +++
376 *** The new option `server-kill-new-buffers' specifies what to do
377 with buffers when done with them. If non-nil, the default, buffers
378 are killed, unless they were already present before visiting them with
379 Emacs Server. If nil, `server-temp-file-regexp' specifies which
380 buffers to kill, as before.
381
382 Please note that only buffers are killed that still have a client,
383 i.e. buffers visited with `emacsclient --no-wait' are never killed in
384 this way.
385
386 ** Changes to Show Paren mode.
387
388 *** Overlays used by Show Paren mode now use a priority property.
389 The new user option show-paren-priority specifies the priority to
390 use. Default is 1000.
391
392 +++
393 ** New command M-x check-parens can be used to find unbalanced paren
394 groups and strings in buffers in Lisp mode (or other modes).
395
396 +++
397 ** You can now easily create new *Info* buffers using either
398 M-x clone-buffer, C-u m <entry> RET or C-u g <entry> RET.
399 M-x clone-buffer can also be used on *Help* and several other special
400 buffers.
401
402 +++
403 ** Emacs can now support 'wheeled' mice (such as the MS IntelliMouse)
404 under XFree86. To enable this, simply put (mwheel-install) in your
405 .emacs file.
406
407 The variables `mwheel-follow-mouse' and `mwheel-scroll-amount'
408 determine where and by how much buffers are scrolled.
409
410 ** Listing buffers with M-x list-buffers (C-x C-b) now shows
411 abbreviated file names. Abbreviations can be customized by changing
412 `directory-abbrev-alist'.
413
414 ** Faces and frame parameters.
415
416 There are four new faces `scroll-bar', `border', `cursor' and `mouse'.
417 Setting the frame parameters `scroll-bar-foreground' and
418 `scroll-bar-background' sets foreground and background color of face
419 `scroll-bar' and vice versa. Setting frame parameter `border-color'
420 sets the background color of face `border' and vice versa. Likewise
421 for frame parameters `cursor-color' and face `cursor', and frame
422 parameter `mouse-color' and face `mouse'.
423
424 Changing frame parameter `font' sets font-related attributes of the
425 `default' face and vice versa. Setting frame parameters
426 `foreground-color' or `background-color' sets the colors of the
427 `default' face and vice versa.
428
429 +++
430 ** New face `menu'.
431
432 The face `menu' can be used to change colors and font of Emacs' menus.
433 Setting the font of LessTif/Motif menus is currently not supported;
434 attempts to set the font are ignored in this case.
435
436 +++
437 ** New frame parameter `screen-gamma' for gamma correction.
438
439 The new frame parameter `screen-gamma' specifies gamma-correction for
440 colors. Its value may be nil, the default, in which case no gamma
441 correction occurs, or a number > 0, usually a float, that specifies
442 the screen gamma of a frame's display.
443
444 PC monitors usually have a screen gamma of 2.2. smaller values result
445 in darker colors. You might want to try a screen gamma of 1.5 for LCD
446 color displays. The viewing gamma Emacs uses is 0.4545. (1/2.2).
447
448 The X resource name of this parameter is `screenGamma', class
449 `ScreenGamma'.
450
451 ** Emacs has a new redisplay engine.
452
453 The new redisplay handles characters of variable width and height.
454 Italic text can be used without redisplay problems. Fonts containing
455 oversized characters, i.e. characters larger than the logical height
456 of a font can be used. Images of various formats can be displayed in
457 the text.
458
459 ** Emacs has a new face implementation.
460
461 The new faces no longer fundamentally use X font names to specify the
462 font. Instead, each face has several independent attributes--family,
463 height, width, weight and slant--that it may or may not specify.
464 These attributes can be merged from various faces, and then together
465 specify a font.
466
467 Faces are supported on terminals that can display color or fonts.
468 These terminal capabilities are auto-detected. Details can be found
469 under Lisp changes, below.
470
471 ** New default font is Courier 12pt.
472
473 +++
474 ** When using a windowing terminal, each Emacs window now has a cursor
475 of its own. When the window is selected, the cursor is solid;
476 otherwise, it is hollow.
477
478 ** Bitmap areas to the left and right of windows are used to display
479 truncation marks, continuation marks, overlay arrows and alike. The
480 foreground, background, and stipple of these areas can be changed by
481 customizing face `fringe'.
482
483 ** The mode line under X is now drawn with shadows by default. You
484 can change its appearance by modifying the face `modeline'.
485
486 ** LessTif support.
487
488 Emacs now runs with the LessTif toolkit (see <http://www.lesstif.org>).
489 You will need a version 0.88.1 or later.
490
491 ** Toolkit scroll bars.
492
493 Emacs now uses toolkit scrollbars if available. When configured for
494 LessTif/Motif, it will use that toolkit's scrollbar. Otherwise, when
495 configured for Lucid and Athena widgets, it will use the Xaw3d scroll
496 bar if Xaw3d is available. You can turn off the use of toolkit scroll
497 bars by specifying `--with-toolkit-scroll-bars=no' when configuring
498 Emacs.
499
500 When you encounter problems with the Xaw3d scroll bar, watch out how
501 Xaw3d is compiled on your system. If the Makefile generated from
502 Xaw3d's Imakefile contains a `-DNARROWPROTO' compiler option, and your
503 Emacs system configuration file `s/your-system.h' does not contain a
504 define for NARROWPROTO, you might consider adding it. Take
505 `s/freebsd.h' as an example.
506
507 Alternatively, if you don't have access to the Xaw3d source code, take
508 a look at your system's imake configuration file, for example in the
509 directory `/usr/X11R6/lib/X11/config' (paths are different on
510 different systems). You will find files `*.cf' there. If your
511 system's cf-file contains a line like `#define NeedWidePrototypes NO',
512 add a `#define NARROWPROTO' to your Emacs system configuration file.
513
514 The reason for this is that one Xaw3d function uses `double' or
515 `float' function parameters depending on the setting of NARROWPROTO.
516 This is not a problem when Imakefiles are used because each system's
517 image configuration file contains the necessary information. Since
518 Emacs doesn't use imake, this has do be done manually.
519
520 ** Toggle buttons and radio buttons in menus.
521
522 When compiled with LessTif (or Motif) support, Emacs uses toolkit
523 widgets for radio and toggle buttons in menus. When configured for
524 Lucid, Emacs draws radio buttons and toggle buttons similar to Motif.
525
526 +++
527 ** Highlighting of trailing whitespace.
528
529 When `show-trailing-whitespace' is non-nil, Emacs displays trailing
530 whitespace in the face `trailing-whitespace'. Trailing whitespace is
531 defined as spaces or tabs at the end of a line. To avoid busy
532 highlighting when entering new text, trailing whitespace is not
533 displayed if point is at the end of the line containing the
534 whitespace.
535
536 +++
537 ** Busy-cursor.
538
539 Emacs can optionally display a busy-cursor under X. You can turn the
540 display on or off by customizing group `cursor'.
541
542 +++
543 ** Blinking cursor
544
545 M-x blink-cursor-mode toggles a blinking cursor under X and on
546 terminals having terminal capabilities `vi', `vs', and `ve'. Blinking
547 and related parameters like frequency and delay can be customized in
548 the group `cursor'.
549
550 ** New font-lock support mode `jit-lock-mode'.
551
552 This support mode is roughly equivalent to `lazy-lock' but is
553 generally faster. It supports stealth and deferred fontification.
554 See the documentation of the function `jit-lock-mode' for more
555 details.
556
557 Font-lock uses jit-lock-mode as default support mode, so you don't
558 have to do anything to activate it.
559
560 ** Tabs and variable-width text.
561
562 Tabs are now displayed with stretch properties; the width of a tab is
563 defined as a multiple of the normal character width of a frame, and is
564 independent of the fonts used in the text where the tab appears.
565 Thus, tabs can be used to line up text in different fonts.
566
567 ** Enhancements of the Lucid menu bar
568
569 +++
570 *** The Lucid menu bar now supports the resource "margin".
571
572 emacs.pane.menubar.margin: 5
573
574 The default margin is 4 which makes the menu bar appear like the
575 LessTif/Motif one.
576
577 *** Arrows that indicate sub-menus are now drawn with shadows, as in
578 LessTif and Motif.
579
580 +++
581 ** Hscrolling in C code.
582
583 Horizontal scrolling now happens automatically if
584 `automatic-hscrolling' is set (the default). This setting can be
585 customized.
586
587 ** Tool bar support.
588
589 Emacs supports a tool bar at the top of a frame under X. For details
590 how to define a tool bar, see the page describing Lisp-level changes.
591 Tool-bar global minor mode controls whether or not it is displayed.
592 To make the tool bar more useful, we need contributions of extra icons
593 for specific modes (with copyright assignments).
594
595 +++
596 ** Mouse-sensitive mode line.
597
598 Different parts of the mode line under X have been made
599 mouse-sensitive. Moving the mouse to a mouse-sensitive part in the mode
600 line changes the appearance of the mouse pointer to an arrow, and help
601 about available mouse actions is displayed either in the echo area, or
602 in the tooltip window if you have enabled one.
603
604 Currently, the following actions have been defined:
605
606 - Mouse-1 on the buffer name in the mode line switches between two
607 buffers.
608
609 - Mouse-2 on the buffer-name switches to the next buffer, and
610 M-mouse-2 switches to the previous buffer in the buffer list.
611
612 - Mouse-3 on the buffer-name displays a buffer menu.
613
614 - Mouse-2 on the read-only or modified status in the mode line (`%' or
615 `*') toggles the status.
616
617 - Mouse-3 on the mode name display a minor-mode menu.
618
619 ** LessTif/Motif file selection dialog.
620
621 When Emacs is configured to use LessTif or Motif, reading a file name
622 from a menu will pop up a file selection dialog if `use-dialog-box' is
623 non-nil.
624
625 ** Emacs can display faces on TTY frames.
626
627 Emacs automatically detects terminals that are able to display colors.
628 Faces with a weight greater than normal are displayed extra-bright, if
629 the terminal supports it. Faces with a weight less than normal and
630 italic faces are displayed dimmed, if the terminal supports it.
631 Underlined faces are displayed underlined if possible. Other face
632 attributes such as `overline', `strike-through', and `box' are ignored
633 on terminals.
634
635 ** Sound support
636
637 Emacs supports playing sound files on GNU/Linux and FreeBSD (Voxware
638 driver and native BSD driver, a.k.a. Luigi's driver). Currently
639 supported file formats are RIFF-WAVE (*.wav) and Sun Audio (*.au).
640
641 +++
642 ** A new variable, backup-by-copying-when-privileged-mismatch, gives
643 the highest file uid for which backup-by-copying-when-mismatch will be
644 forced on. The assumption is that uids less than or equal to this
645 value are special uids (root, bin, daemon, etc.--not real system
646 users) and that files owned by these users should not change ownership,
647 even if your system policy allows users other than root to edit them.
648
649 The default is 200; set the variable to nil to disable the feature.
650
651 +++
652 ** A block cursor can be drawn as wide as the glyph under it under X.
653
654 As an example: if a block cursor is over a tab character, it will be
655 drawn as wide as that tab on the display. To do this, set
656 `x-stretch-cursor' to a non-nil value.
657
658 +++
659 ** Empty display lines at the end of a buffer may be marked with a
660 bitmap (this is similar to the tilde displayed by vi).
661
662 This behavior is activated by setting the buffer-local variable
663 `indicate-empty-lines' to a non-nil value. The default value of this
664 variable is found in `default-indicate-empty-lines'.
665
666 +++
667 ** There is a new "aggressive" scrolling method.
668
669 When scrolling up because point is above the window start, if the
670 value of the buffer-local variable `scroll-up-aggessively' is a
671 number, Emacs chooses a new window start so that point ends up that
672 fraction of the window's height from the top of the window.
673
674 When scrolling down because point is below the window end, if the
675 value of the buffer-local variable `scroll-down-aggessively' is a
676 number, Emacs chooses a new window start so that point ends up that
677 fraction of the window's height from the bottom of the window.
678
679 ** The rectangle commands now avoid inserting undesirable spaces,
680 notably at the end of lines.
681
682 All these functions have been rewritten to avoid inserting unwanted
683 spaces, and an optional prefix now allows them to behave the old way.
684
685 +++
686 There is a new command M-x replace-rectangle.
687
688 ** The new command M-x query-replace-regexp-eval acts like
689 query-replace-regexp, but takes a Lisp expression which is evaluated
690 after each match to get the replacement text.
691
692 +++
693 ** M-x query-replace recognizes a new command `e' (or `E') that lets
694 you edit the replacement string.
695
696 ** The new command mail-abbrev-complete-alias, bound to `M-TAB', lets
697 you complete mail aliases in the text, analogous to
698 lisp-complete-symbol.
699
700 +++
701 ** Emacs now resizes mini-windows if appropriate.
702
703 If a message is longer than one line, or minibuffer contents are
704 longer than one line, Emacs now resizes the minibuffer window unless
705 it is on a frame of its own. You can control the maximum minibuffer
706 window size by setting the following variable:
707
708 - User option: max-mini-window-height
709
710 Maximum height for resizing mini-windows. If a float, it specifies a
711 fraction of the mini-window frame's height. If an integer, it
712 specifies a number of lines. If nil, don't resize.
713
714 Default is 0.25.
715
716 ** The command `Info-search' now uses a search history.
717
718 ** Changes to hideshow.el
719
720 Hideshow is now at version 5.x. It uses a new algorithms for block
721 selection and traversal, includes more isearch support, and has more
722 conventional keybindings.
723
724 *** Generalized block selection and traversal
725
726 A block is now recognized by three things: its start and end regexps
727 (both strings), and a match-data selector (an integer) specifying
728 which sub-expression in the start regexp serves as the place where a
729 `forward-sexp'-like function can operate. Hideshow always adjusts
730 point to this sub-expression before calling `hs-forward-sexp-func'
731 (which for most modes evaluates to `forward-sexp').
732
733 If the match-data selector is not specified, it defaults to zero,
734 i.e., the entire start regexp is valid, w/ no prefix. This is
735 backwards compatible with previous versions of hideshow. Please see
736 the docstring for variable `hs-special-modes-alist' for details.
737
738 *** Isearch support for updating mode line
739
740 During incremental search, if Hideshow minor mode is active, hidden
741 blocks are temporarily shown. The variable `hs-headline' records the
742 line at the beginning of the opened block (preceding the hidden
743 portion of the buffer), and the mode line is refreshed. When a block
744 is re-hidden, the variable is set to nil.
745
746 To show `hs-headline' in the mode line, you may wish to include
747 something like this in your .emacs.
748
749 (add-hook 'hs-minor-mode-hook
750 (lambda ()
751 (add-to-list 'mode-line-format 'hs-headline)))
752
753 *** New customization var: `hs-hide-all-non-comment-function'
754
755 Normally, `hs-hide-all' hides everything, leaving only the
756 header lines of top-level forms (and comments, unless var
757 `hs-hide-comments-when-hiding-all' is non-nil). It does this by
758 moving point to each top-level block beginning and hiding the
759 block there. In some major modes (for example, Java), this
760 behavior results in few blocks left visible, which may not be so
761 useful.
762
763 You can now set var `hs-hide-all-non-comment-function' to a
764 function to be called at each top-level block beginning, instead
765 of the normal block-hiding function. For example, the following
766 code defines a function to hide one level down and move point
767 appropriately, and then tells hideshow to use the new function.
768
769 (defun ttn-hs-hide-level-1 ()
770 (hs-hide-level 1)
771 (forward-sexp 1))
772 (setq hs-hide-all-non-comment-function 'ttn-hs-hide-level-1)
773
774 The name `hs-hide-all-non-comment-function' was chosen to
775 emphasize that this function is not called for comment blocks,
776 only for code blocks.
777
778 *** Command deleted: `hs-show-region'
779
780 Historical Note: This command was added to handle "unbalanced
781 parentheses" emergencies back when hideshow.el used selective
782 display for implementation.
783
784 *** Commands rebound to more conventional keys
785
786 The hideshow commands used to be bound to keys of the form "C-c
787 LETTER". This is contrary to the Emacs keybinding convention,
788 which reserves that space for user modification. Here are the
789 new bindings (which includes the addition of `hs-toggle-hiding'):
790
791 hs-hide-block C-c C-h
792 hs-show-block C-c C-s
793 hs-hide-all C-c C-M-h
794 hs-show-all C-c C-M-s
795 hs-hide-level C-c C-l
796 hs-toggle-hiding C-c C-c
797 hs-mouse-toggle-hiding [(shift button-2)]
798
799 These were chosen to roughly imitate those used by Outline mode.
800
801 ** Changes to Change Log mode and Add-Log functions
802
803 +++
804 *** If you invoke `add-change-log-entry' from a backup file, it makes
805 an entry appropriate for the file's parent. This is useful for making
806 log entries by comparing a version with deleted functions.
807
808 +++
809 **** New command M-x change-log-merge merges another log into the
810 current buffer.
811
812 +++
813 *** New command M-x change-log-redate fixes any old-style date entries
814 in a log file.
815
816 +++
817 *** Change Log mode now adds a file's version number to change log
818 entries if user-option `change-log-version-info-enabled' is non-nil.
819
820 +++
821 *** Unless the file is under version control the search for a file's
822 version number is performed based on regular expressions from
823 `change-log-version-number-regexp-list' which can be cutomized.
824 Version numbers are only found in the first 10 percent of a file.
825
826 *** Change Log mode now defines its own faces for font-lock
827 highlighting.
828
829 ** Changes in Font Lock
830
831 *** The new function `font-lock-remove-keywords' can be used to remove
832 font-lock keywords from the current buffer or from a specific major
833 mode.
834
835 ** Comint (subshell) changes
836
837 By default, comint no longer uses the variable `comint-prompt-regexp' to
838 distinguish prompts from user-input. Instead, it notices which parts of
839 the text were output by the process, and which entered by the user, and
840 attaches `field' properties to allow emacs commands to use this information.
841 Common movement commands, notably beginning-of-line, respect field
842 boundaries in a fairly natural manner.
843 To disable this feature, and use the old behavior, set the variable
844 `comint-use-prompt-regexp-instead-of-fields' to a non-nil value.
845
846 Comint now includes new features to send commands to running processes
847 and redirect the output to a designated buffer or buffers.
848
849 The command M-x comint-redirect-send-command reads a command and
850 buffer name from the mini-buffer. The command is sent to the current
851 buffer's process, and its output is inserted into the specified buffer.
852
853 The command M-x comint-redirect-send-command-to-process acts like
854 M-x comint-redirect-send-command but additionally reads the name of
855 the buffer whose process should be used from the mini-buffer.
856
857 Packages based on comint.el like shell-mode, and scheme-interaction-mode
858 now highlight user input and program prompts, and support choosing
859 previous input with mouse-2. To control these feature, see the
860 user-options `comint-highlight-input' and `comint-highlight-prompt'.
861
862 ** Changes to Rmail mode
863
864 *** The new user-option rmail-rmail-user-mail-address-regexp can be
865 set to fine tune the identification of of the correspondent when
866 receiving new mail. If it matches the address of the sender, the
867 recipient is taken as correspondent of a mail. If nil, the default,
868 `user-login-name' and `user-mail-address' are used to exclude yourself
869 as correspondent.
870
871 Usually you don't have to set this variable, except if you collect
872 mails sent by you under different user names. Then it should be a
873 regexp matching your mail addresses.
874
875 *** The new user-option rmail-confirm-expunge controls whether and how
876 to ask for confirmation before expunging deleted messages from an
877 Rmail file. You can choose between no confirmation, confirmation
878 with y-or-n-p, or confirmation with yes-or-no-p. Default is to ask
879 for confirmation with yes-or-no-p.
880
881 *** RET is now bound in the Rmail summary to rmail-summary-goto-msg,
882 like `j'.
883
884 *** There is a new user option `rmail-digest-end-regexps' that
885 specifies the regular expressions to detect the line that ends a
886 digest message.
887
888 *** The new user option `rmail-automatic-folder-directives' specifies
889 in which folder to put messages automatically.
890
891 ** Changes to TeX mode
892
893 The default mode has been changed from `plain-tex-mode' to
894 `latex-mode'.
895
896 ** Changes to RefTeX mode
897
898 *** RefTeX has new support for index generation. Index entries can be
899 created with `C-c <', with completion available on index keys.
900 Pressing `C-c /' indexes the word at the cursor with a default
901 macro. `C-c >' compiles all index entries into an alphabetically
902 sorted *Index* buffer which looks like the final index. Entries
903 can be edited from that buffer.
904
905 *** Label and citation key selection now allow to select several
906 items and reference them together (use `m' to mark items, `a' or
907 `A' to use all marked entries).
908
909 *** reftex.el has been split into a number of smaller files to reduce
910 memory use when only a part of RefTeX is being used.
911
912 *** a new command `reftex-view-crossref-from-bibtex' (bound to `C-c &'
913 in BibTeX-mode) can be called in a BibTeX database buffer in order
914 to show locations in LaTeX documents where a particular entry has
915 been cited.
916
917 ** Emacs Lisp mode now allows multiple levels of outline headings.
918 The level of a heading is determined from the number of leading
919 semicolons in a heading line. Toplevel forms starting with a `('
920 in column 1 are always made leaves.
921
922 ** The M-x time-stamp command (most commonly used on write-file-hooks)
923 has the following new features:
924
925 *** The patterns for finding the time stamp and for updating a pattern
926 may match text spanning multiple lines. For example, some people like
927 to have the filename and date on separate lines. The new variable
928 time-stamp-inserts-lines controls the matching for multi-line patterns.
929
930 *** More than one time stamp can be updated in the same file. This
931 feature is useful if you need separate time stamps in a program source
932 file to both include in formatted documentation and insert in the
933 compiled binary. The same time-stamp will be written at each matching
934 pattern. The variable time-stamp-count enables this new feature; it
935 defaults to 1.
936
937 ** Partial Completion mode now completes environment variables in
938 file names.
939
940 +++
941 ** Tooltips.
942
943 Tooltips are small X windows displaying a help string at the current
944 mouse position. To use them, use the Lisp package `tooltip' which you
945 can access via the user option `tooltip-mode'.
946
947 Tooltips also provides support for GUD debugging. If activated,
948 variable values can be displayed in tooltips by pointing at them with
949 the mouse in source buffers. You can customize various aspects of the
950 tooltip display in the group `tooltip'.
951
952 +++
953 ** Customize changes
954
955 *** Customize now supports comments about customized items. Use the
956 `State' menu to add comments. Note that customization comments will
957 cause the customizations to fail in earlier versions of Emacs.
958
959 *** The new option `custom-buffer-done-function' says whether to kill
960 Custom buffers when you've done with them or just bury them (the
961 default).
962
963 *** The keyword :set-after in defcustom allows to specify dependencies
964 between custom options. Example:
965
966 (defcustom default-input-method nil
967 "*Default input method for multilingual text (a string).
968 This is the input method activated automatically by the command
969 `toggle-input-method' (\\[toggle-input-method])."
970 :group 'mule
971 :type '(choice (const nil) string)
972 :set-after '(current-language-environment))
973
974 This specifies that default-input-method should be set after
975 current-language-environment even if default-input-method appears
976 first in a custom-set-variables statement.
977
978 ** New features in evaluation commands
979
980 *** The commands to evaluate Lisp expressions, such as C-M-x in Lisp
981 modes, C-j in Lisp Interaction mode, and M-:, now bind the variables
982 print-level, print-length, and debug-on-error based on the
983 customizable variables eval-expression-print-level,
984 eval-expression-print-length, and eval-expression-debug-on-error.
985
986 *** The function `eval-defun' (M-C-x) now loads Edebug and instruments
987 code when called with a prefix argument.
988
989 ** Ispell changes
990
991 +++
992 *** The command `ispell' now spell-checks a region if
993 transient-mark-mode is on, and the mark is active. Otherwise it
994 spell-checks the current buffer.
995
996 +++
997 *** Support for synchronous subprocesses - DOS/Windoze - has been
998 added.
999
1000 *** An "alignment error" bug was fixed when a manual spelling
1001 correction is made and re-checked.
1002
1003 *** An Italian and a Portuguese dictionary definition has been added.
1004
1005 *** Region skipping performance has been vastly improved in some
1006 cases.
1007
1008 *** Spell checking HTML buffers has been improved and isn't so strict
1009 on syntax errors.
1010
1011 *** The buffer-local words are now always placed on a new line at the
1012 end of the buffer.
1013
1014 ** Dired changes
1015
1016 *** New variable `dired-recursive-deletes' determines if the delete
1017 command will delete non-empty directories recursively. The default
1018 is, delete only empty directories.
1019
1020 *** New variable `dired-recursive-copies' determines if the copy
1021 command will copy directories recursively. The default is, do not
1022 copy directories recursively.
1023
1024 *** In command `dired-do-shell-command' (usually bound to `!') a `?'
1025 in the shell command has a special meaning similar to `*', but with
1026 the difference that the command will be run on each file individually.
1027
1028 *** The new command `dired-find-alternate-file' (usually bound to `a')
1029 replaces the Dired buffer with the buffer for an alternate file or
1030 directory.
1031
1032 *** The new command `dired-show-file-type' (usually bound to `w') shows
1033 a message in the echo area describing what type of file the point is on.
1034 This command invokes the external program `file' do its work, and so
1035 will only work on systems with that program, and will be only as
1036 accurate or inaccurate as it is.
1037
1038 *** Dired now properly handles undo changes of adding/removing `-R'
1039 from ls switches.
1040
1041 ** The variable mail-specify-envelope-from controls whether to
1042 use the -f option when sending mail.
1043
1044 ** CC mode changes.
1045
1046 Note: This release contains changes that might not be compatible with
1047 current user setups (although it's believed that these
1048 incompatibilities will only show in very uncommon circumstances).
1049 However, since the impact is uncertain, these changes may be rolled
1050 back depending on user feedback. Therefore there's no forward
1051 compatibility guarantee wrt the new features introduced in this
1052 release.
1053
1054 *** c-style-variables-are-local-p now defaults to t.
1055 This is an incompatible change that has been made to make the behavior
1056 of the style system wrt global variable settings less confusing for
1057 non-advanced users. If you know what this variable does you might
1058 want to set it to nil in your .emacs, otherwise you probably don't
1059 have to bother.
1060
1061 Defaulting c-style-variables-are-local-p to t avoids the confusing
1062 situation that occurs when a user sets some style variables globally
1063 and edits both a Java and a non-Java file in the same Emacs session.
1064 If the style variables aren't buffer local in this case, loading of
1065 the second file will cause the default style (either "gnu" or "java"
1066 by default) to override the global settings made by the user.
1067
1068 *** New initialization procedure for the style system.
1069 When the initial style for a buffer is determined by CC Mode (from the
1070 variable c-default-style), the global values of style variables now
1071 take precedence over the values specified by the chosen style. This
1072 is different than the old behavior: previously, the style-specific
1073 settings would override the global settings. This change makes it
1074 possible to do simple configuration in the intuitive way with
1075 Customize or with setq lines in one's .emacs file.
1076
1077 By default, the global value of every style variable is the new
1078 special symbol set-from-style, which causes the value to be taken from
1079 the style system. This means that in effect, only an explicit setting
1080 of a style variable will cause the "overriding" behavior described
1081 above.
1082
1083 Also note that global settings override style-specific settings *only*
1084 when the initial style of a buffer is chosen by a CC Mode major mode
1085 function. When a style is chosen in other ways --- for example, by a
1086 call like (c-set-style "gnu") in a hook, or via M-x c-set-style ---
1087 then the style-specific values take precedence over any global style
1088 values. In Lisp terms, global values override style-specific values
1089 only when the new second argument to c-set-style is non-nil; see the
1090 function documentation for more info.
1091
1092 The purpose of these changes is to make it easier for users,
1093 especially novice users, to do simple customizations with Customize or
1094 with setq in their .emacs files. On the other hand, the new system is
1095 intended to be compatible with advanced users' customizations as well,
1096 such as those that choose styles in hooks or whatnot. This new system
1097 is believed to be almost entirely compatible with current
1098 configurations, in spite of the changed precedence between style and
1099 global variable settings when a buffer's default style is set.
1100
1101 (Thanks to Eric Eide for clarifying this explanation a bit.)
1102
1103 **** c-offsets-alist is now a customizable variable.
1104 This became possible as a result of the new initialization behavior.
1105
1106 This variable is treated slightly differently from the other style
1107 variables; instead of using the symbol set-from-style, it will be
1108 completed with the syntactic symbols it doesn't already contain when
1109 the style is first initialized. This means it now defaults to the
1110 empty list to make all syntactic elements get their values from the
1111 style system.
1112
1113 **** Compatibility variable to restore the old behavior.
1114 In case your configuration doesn't work with this change, you can set
1115 c-old-style-variable-behavior to non-nil to get the old behavior back
1116 as far as possible.
1117
1118 *** Improvements to line breaking and text filling.
1119 CC Mode now handles this more intelligently and seamlessly wrt the
1120 surrounding code, especially inside comments. For details see the new
1121 chapter about this in the manual.
1122
1123 **** New variable to recognize comment line prefix decorations.
1124 The variable c-comment-prefix-regexp has been added to properly
1125 recognize the line prefix in both block and line comments. It's
1126 primarily used to initialize the various paragraph recognition and
1127 adaptive filling variables that the text handling functions uses.
1128
1129 **** New variable c-block-comment-prefix.
1130 This is a generalization of the now obsolete variable
1131 c-comment-continuation-stars to handle arbitrary strings.
1132
1133 **** CC Mode now uses adaptive fill mode.
1134 This to make it adapt better to the paragraph style inside comments.
1135
1136 It's also possible to use other adaptive filling packages inside CC
1137 Mode, notably Kyle E. Jones' Filladapt mode (http://wonderworks.com/).
1138 A new convenience function c-setup-filladapt sets up Filladapt for use
1139 inside CC Mode.
1140
1141 Note though that the 2.12 version of Filladapt lacks a feature that
1142 causes it to work suboptimally when c-comment-prefix-regexp can match
1143 the empty string (which it commonly does). A patch for that is
1144 available from the CC Mode web site (http://www.python.org/emacs/
1145 cc-mode/).
1146
1147 **** It's now possible to selectively turn off auto filling.
1148 The variable c-ignore-auto-fill is used to ignore auto fill mode in
1149 specific contexts, e.g. in preprocessor directives and in string
1150 literals.
1151
1152 **** New context sensitive line break function c-context-line-break.
1153 It works like newline-and-indent in normal code, and adapts the line
1154 prefix according to the comment style when used inside comments. If
1155 you're normally using newline-and-indent, you might want to switch to
1156 this function.
1157
1158 *** Fixes to IDL mode.
1159 It now does a better job in recognizing only the constructs relevant
1160 to IDL. E.g. it no longer matches "class" as the beginning of a
1161 struct block, but it does match the CORBA 2.3 "valuetype" keyword.
1162 Thanks to Eric Eide.
1163
1164 *** Improvements to the Whitesmith style.
1165 It now keeps the style consistently on all levels and both when
1166 opening braces hangs and when they don't.
1167
1168 **** New lineup function c-lineup-whitesmith-in-block.
1169
1170 *** New lineup functions c-lineup-template-args and c-indent-multi-line-block.
1171 See their docstrings for details. c-lineup-template-args does a
1172 better job of tracking the brackets used as parens in C++ templates,
1173 and is used by default to line up continued template arguments.
1174
1175 *** c-lineup-comment now preserves alignment with a comment on the
1176 previous line. It used to instead preserve comments that started in
1177 the column specified by comment-column.
1178
1179 *** c-lineup-C-comments handles "free form" text comments.
1180 In comments with a long delimiter line at the start, the indentation
1181 is kept unchanged for lines that start with an empty comment line
1182 prefix. This is intended for the type of large block comments that
1183 contain documentation with its own formatting. In these you normally
1184 don't want CC Mode to change the indentation.
1185
1186 *** The `c' syntactic symbol is now relative to the comment start
1187 instead of the previous line, to make integers usable as lineup
1188 arguments.
1189
1190 *** All lineup functions have gotten docstrings.
1191
1192 *** More preprocessor directive movement functions.
1193 c-down-conditional does the reverse of c-up-conditional.
1194 c-up-conditional-with-else and c-down-conditional-with-else are
1195 variants of these that also stops at "#else" lines (suggested by Don
1196 Provan).
1197
1198 *** Minor improvements to many movement functions in tricky situations.
1199
1200 ** Makefile mode changes
1201
1202 *** The mode now uses the abbrev table `makefile-mode-abbrev-table'.
1203
1204 *** Conditionals and include statements are now highlighted when
1205 Fontlock mode is active.
1206
1207 ** Isearch changes
1208
1209 *** Isearch now puts a call to `isearch-resume' in the command history,
1210 so that searches can be resumed.
1211
1212 *** In Isearch mode, M-C-s and M-C-r are now bound like C-s and C-r,
1213 respectively, i.e. you can repeat a regexp isearch with the same keys
1214 that started the search.
1215
1216 *** In Isearch mode, mouse-2 in the echo area now yanks the current
1217 selection into the search string rather than giving an error.
1218
1219 +++
1220 *** There is a new lazy highlighting feature in incremental search.
1221
1222 Lazy highlighting is switched on/off by customizing variable
1223 `isearch-lazy-highlight'. When active, all matches for the current
1224 search string are highlighted. The current match is highlighted as
1225 before using face `isearch' or `region'. All other matches are
1226 highlighted using face `isearch-lazy-highlight-face' which defaults to
1227 `secondary-selection'.
1228
1229 The extra highlighting makes it easier to anticipate where the cursor
1230 will end up each time you press C-s or C-r to repeat a pending search.
1231 Highlighting of these additional matches happens in a deferred fashion
1232 using "idle timers," so the cycles needed do not rob isearch of its
1233 usual snappy response.
1234
1235 If `isearch-lazy-highlight-cleanup' is set to t, highlights for
1236 matches are automatically cleared when you end the search. If it is
1237 set to nil, you can remove the highlights manually with `M-x
1238 isearch-lazy-highlight-cleanup'.
1239
1240 +++
1241 ** Changes in sort.el
1242
1243 The function sort-numeric-fields interprets numbers starting with `0'
1244 as octal and numbers starting with `0x' or `0X' as hexadecimal. The
1245 new user-option sort-numeric-base can be used to specify a default
1246 numeric base.
1247
1248 ** Changes to Ange-ftp
1249
1250 +++
1251 *** Ange-ftp allows you to specify of a port number in remote file
1252 names cleanly. It is appended to the host name, separated by a hash
1253 sign, e.g. `/foo@bar.org#666:mumble'. (This syntax comes from EFS.)
1254
1255 *** If the new user-option `ange-ftp-try-passive-mode' is set, passive
1256 ftp mode will be used if the ftp client supports that.
1257
1258 *** Ange-ftp handles the output of the w32-style clients which
1259 output ^M at the end of lines.
1260
1261 ** Shell script mode changes.
1262
1263 Shell script mode (sh-script) can now indent scripts for shells
1264 derived from sh and rc. The indentation style is customizeable, and
1265 sh-script can attempt to "learn" the current buffer's style.
1266
1267 ** Etags changes.
1268
1269 *** In DOS, etags looks for file.cgz if it cannot find file.c.
1270
1271 *** New option --ignore-case-regex is an alternative to --regex. It is now
1272 possible to bind a regexp to a language, by prepending the regexp with
1273 {lang}, where lang is one of the languages that `etags --help' prints out.
1274 This feature is useful especially for regex files, where each line contains
1275 a regular expression. The manual contains details.
1276
1277 *** In C and derived languages, etags creates tags for function
1278 declarations when given the --declarations option.
1279
1280 *** In C++, tags are created for "operator". The tags have the form
1281 "operator+", without spaces between the keyword and the operator.
1282
1283 *** New language Ada: tags are functions, procedures, packages, tasks, and
1284 types.
1285
1286 *** In Fortran, `procedure' is not tagged.
1287
1288 *** In Java, tags are created for "interface".
1289
1290 *** In Lisp, "(defstruct (foo", "(defun (operator" and similar constructs
1291 are now tagged.
1292
1293 *** In Perl, the --globals option tags global variables. my and local
1294 variables are tagged.
1295
1296 *** New language Python: def and class at the beginning of a line are tags.
1297
1298 *** .ss files are Scheme files, .pdb is Postscript with C syntax, .psw is
1299 for PSWrap.
1300
1301 +++
1302 ** Changes in etags.el
1303
1304 *** The new user-option tags-case-fold-search can be used to make
1305 tags operations case-sensitive or case-insensitive. The default
1306 is to use the same setting as case-fold-search.
1307
1308 *** You can display additional output with M-x tags-apropos by setting
1309 the new variable tags-apropos-additional-actions.
1310
1311 If non-nil, the variable's value should be a list of triples (TITLE
1312 FUNCTION TO-SEARCH). For each triple, M-x tags-apropos processes
1313 TO-SEARCH and lists tags from it. TO-SEARCH should be an alist,
1314 obarray, or symbol. If it is a symbol, the symbol's value is used.
1315
1316 TITLE is a string to use to label the list of tags from TO-SEARCH.
1317
1318 FUNCTION is a function to call when an entry is selected in the Tags
1319 List buffer. It is called with one argument, the selected symbol.
1320
1321 A useful example value for this variable might be something like:
1322
1323 '(("Emacs Lisp" Info-goto-emacs-command-node obarray)
1324 ("Common Lisp" common-lisp-hyperspec common-lisp-hyperspec-obarray)
1325 ("SCWM" scwm-documentation scwm-obarray))
1326
1327 *** The face tags-tag-face can be used to customize the appearance
1328 of tags in the output of M-x tags-apropos.
1329
1330 *** Setting tags-apropos-verbose to a non-nil value displays the
1331 names of tags files in the *Tags List* buffer.
1332
1333 +++
1334 ** Emacs now attempts to determine the initial language environment
1335 and preferred and locale coding systems systematically from the
1336 LC_ALL, LC_CTYPE, and LANG environment variables during startup.
1337
1338 +++
1339 ** New language environments `Polish', `Latin-8' and `Latin-9'.
1340 Latin-8 and Latin-9 correspond respectively to the ISO character sets
1341 8859-14 (Celtic) and 8859-15 (updated Latin-1, with the Euro sign).
1342 GNU Intlfonts doesn't support these yet; there are basic 8859-14 and
1343 8859-15 fonts at <URL:http://czyborra.com/charsets/> and recent X
1344 releases have 8859-15. There are new Latin-8 and Latin-9 prefix
1345 (only) and Polish slash input methods in Leim.
1346
1347 +++
1348 ** Fortran mode has a new command `fortran-strip-sequence-nos' to
1349 remove text past column 72. The syntax class of `\' in Fortran is now
1350 appropriate for C-style escape sequences in strings.
1351
1352 ** SGML mode's default `sgml-validate-command' is now `nsgmls'.
1353
1354 +++
1355 ** A new command `view-emacs-problems' (C-h P) displays the PROBLEMS file.
1356
1357 +++
1358 ** The Dabbrev package has a new user-option `dabbrev-ignored-regexps'
1359 containing a list of regular expressions. Buffers matching a regular
1360 expression from that list, are not checked.
1361
1362 ** Emacs can now figure out modification times of remote files.
1363 When you do C-x C-f /user@host:/path/file RET and edit the file,
1364 and someone else modifies the file, you will be prompted to revert
1365 the buffer, just like for the local files.
1366
1367 ** The buffer menu (C-x C-b) no longer lists the *Buffer List* buffer.
1368
1369 +++
1370 ** When invoked with a prefix argument, the command `list-abbrevs' now
1371 displays local abbrevs, only.
1372
1373 ** VC Changes
1374
1375 VC has been overhauled internally. It is now modular, making it
1376 easier to plug-in arbitrary version control backends. (See Lisp
1377 Changes for details on the new structure.) As a result, the mechanism
1378 to enable and disable support for particular version systems has
1379 changed: everything is now controlled by the new variable
1380 `vc-handled-backends'. Its value is a list of atoms that identify
1381 version systems; the default is '(RCS CVS SCCS). When finding a file,
1382 each of the backends in that list is tried in order to see whether the
1383 file is registered in that backend.
1384
1385 When registering a new file, VC first tries each of the listed
1386 backends to see if any of them considers itself "responsible" for the
1387 directory of the file (e.g. because a corresponding subdirectory for
1388 master files exists). If none of the backends is responsible, then
1389 the first backend in the list that could register the file is chosen.
1390 As a consequence, the variable `vc-default-back-end' is now obsolete.
1391
1392 The old variable `vc-master-templates' is also obsolete, although VC
1393 still supports it for backward compatibility. To define templates for
1394 RCS or SCCS, you should rather use the new variables
1395 vc-{rcs,sccs}-master-templates. (There is no such feature under CVS
1396 where it doesn't make sense.)
1397
1398 The variables `vc-ignore-vc-files' and `vc-handle-cvs' are also
1399 obsolete now, you must set `vc-handled-backends' to nil or exclude
1400 `CVS' from the list, respectively, to achieve their effect now.
1401
1402 *** General Changes
1403
1404 The variable `vc-checkout-carefully' is obsolete: the corresponding
1405 checks are always done now.
1406
1407 VC Dired buffers are now kept up-to-date during all version control
1408 operations.
1409
1410 *** Changes for CVS
1411
1412 There is a new user option, `vc-cvs-stay-local'. If it is `t' (the
1413 default), then VC avoids network queries for files registered in
1414 remote repositories. The state of such files is then only determined
1415 by heuristics and past information. `vc-cvs-stay-local' can also be a
1416 regexp to match against repository hostnames; only files from hosts
1417 that match it are treated locally. If the variable is nil, then VC
1418 queries the repository just as often as it does for local files.
1419
1420 If `vc-cvs-stay-local' is on, and there have been changes in the
1421 repository, VC notifies you about it when you actually try to commit.
1422 If you want to check for updates from the repository without trying to
1423 commit, you can either use C-u C-x v m to perform an update on the
1424 current file, or you can use C-x v r RET to get an update for an
1425 entire directory tree.
1426
1427 The new user option `vc-cvs-use-edit' indicates whether VC should call
1428 "cvs edit" to make files writeable; it defaults to `t'. (This option
1429 is only meaningful if the CVSREAD variable is set, or if files are
1430 "watched" by other developers.)
1431
1432 *** Lisp Changes in VC
1433
1434 VC has been restructured internally to make it modular. You can now
1435 add support for arbitrary version control backends by writing a
1436 library that provides a certain set of backend-specific functions, and
1437 then telling VC to use that library. For example, to add support for
1438 a version system named FOO, you write a library named vc-foo.el, which
1439 provides a number of functions vc-foo-... (see commentary at the end
1440 of vc.el for a detailed list of them). To make VC use that library,
1441 you need to put it somewhere into Emacs' load path and add the atom
1442 `FOO' to the list `vc-handled-backends'.
1443
1444 ** New modes and packages
1445
1446 +++
1447 *** The new package timeclock.el is a mode is for keeping track of time
1448 intervals. You can use it for whatever purpose you like, but the
1449 typical scenario is to keep track of how much time you spend working
1450 on certain projects.
1451
1452 +++
1453 *** The new package hi-lock.el, text matching interactively entered
1454 regexp's can be highlighted. For example,
1455
1456 M-x highlight-regexp RET clearly RET RET
1457
1458 will highlight all occurrences of `clearly' using a yellow background
1459 face. New occurrences of `clearly' will be highlighted as they are
1460 typed. `M-x unhighlight-regexp RET' will remove the highlighting.
1461 Any existing face can be used for highlighting and a set of
1462 appropriate faces is provided. The regexps can be written into the
1463 current buffer in a form that will be recognized the next time the
1464 corresponding file is read.
1465
1466 +++
1467 *** The new package zone.el plays games with Emacs' display when
1468 Emacs is idle.
1469
1470 *** The new package xml.el provides a simple but generic XML
1471 parser. It doesn't parse the DTDs however.
1472
1473 *** The comment operations are now provided by the newcomment.el
1474 package which allows different styles of comment-region and should
1475 be more robust while offering the same functionality.
1476
1477 +++
1478 *** The Ebrowse package implements a C++ class browser and tags
1479 facilities tailored for use with C++. It is documented in a
1480 separate Texinfo file.
1481
1482 +++
1483 *** The PCL-CVS package available by either running M-x cvs-examine or
1484 by visiting a CVS administrative directory (with a prefix argument)
1485 provides an alternative interface to VC-dired for CVS. It comes with
1486 `log-view-mode' to view RCS and SCCS logs and `log-edit-mode' used to
1487 enter checkin log messages.
1488
1489 +++
1490 *** The new package called `woman' allows to browse Unix man pages
1491 without invoking external programs.
1492
1493 The command `M-x woman' formats manual pages entirely in Emacs Lisp
1494 and then displays them, like `M-x manual-entry' does. Unlike
1495 `manual-entry', `woman' does not invoke any external programs, so it
1496 is useful on systems such as MS-DOS/MS-Windows where the `man' and
1497 Groff or `troff' commands are not readily available.
1498
1499 The command `M-x woman-find-file' asks for the file name of a man
1500 page, then formats and displays it like `M-x woman' does.
1501
1502 +++
1503 *** The new command M-x re-builder offers a convenient interface for
1504 authoring regular expressions with immediate visual feedback.
1505
1506 The buffer from which the command was called becomes the target for
1507 the regexp editor popping up in a separate window. Matching text in
1508 the target buffer is immediately color marked during the editing.
1509 Each sub-expression of the regexp will show up in a different face so
1510 even complex regexps can be edited and verified on target data in a
1511 single step.
1512
1513 On displays not supporting faces the matches instead blink like
1514 matching parens to make them stand out. On such a setup you will
1515 probably also want to use the sub-expression mode when the regexp
1516 contains such to get feedback about their respective limits.
1517
1518 +++
1519 *** glasses-mode is a minor mode that makes
1520 unreadableIdentifiersLikeThis readable. It works as glasses, without
1521 actually modifying content of a buffer.
1522
1523 *** The package ebnf2ps translates an EBNF to a syntactic chart in
1524 PostScript.
1525
1526 Currently accepts ad-hoc EBNF, ISO EBNF and Bison/Yacc.
1527
1528 The ad-hoc default EBNF syntax has the following elements:
1529
1530 ; comment (until end of line)
1531 A non-terminal
1532 "C" terminal
1533 ?C? special
1534 $A default non-terminal
1535 $"C" default terminal
1536 $?C? default special
1537 A = B. production (A is the header and B the body)
1538 C D sequence (C occurs before D)
1539 C | D alternative (C or D occurs)
1540 A - B exception (A excluding B, B without any non-terminal)
1541 n * A repetition (A repeats n (integer) times)
1542 (C) group (expression C is grouped together)
1543 [C] optional (C may or not occurs)
1544 C+ one or more occurrences of C
1545 {C}+ one or more occurrences of C
1546 {C}* zero or more occurrences of C
1547 {C} zero or more occurrences of C
1548 C / D equivalent to: C {D C}*
1549 {C || D}+ equivalent to: C {D C}*
1550 {C || D}* equivalent to: [C {D C}*]
1551 {C || D} equivalent to: [C {D C}*]
1552
1553 Please, see ebnf2ps documentation for EBNF syntax and how to use it.
1554
1555 *** The package align.el will align columns within a region, using M-x
1556 align. Its mode-specific rules, based on regular expressions,
1557 determine where the columns should be split. In C and C++, for
1558 example, it will align variable names in declaration lists, or the
1559 equal signs of assignments.
1560
1561 +++
1562 *** `paragraph-indent-minor-mode' is a new minor mode supporting
1563 paragraphs in the same style as `paragraph-indent-text-mode'.
1564
1565 +++
1566 *** bs.el is a new package for buffer selection similar to
1567 list-buffers or electric-buffer-list. Use M-x bs-show to display a
1568 buffer menu with this package. You can use M-x bs-customize to
1569 customize the package.
1570
1571 *** find-lisp.el is a package emulating the Unix find command in Lisp.
1572
1573 *** calculator.el is a small calculator package that is intended to
1574 replace desktop calculators such as xcalc and calc.exe. Actually, it
1575 is not too small - it has more features than most desktop calculators,
1576 and can be customized easily to get many more functions. It should
1577 not be confused with "calc" which is a much bigger mathematical tool
1578 which answers different needs.
1579
1580 +++
1581 *** The minor modes cwarn-mode and global-cwarn-mode highlights
1582 suspicious C and C++ constructions. Currently, assignments inside
1583 expressions, semicolon following `if', `for' and `while' (except, of
1584 course, after a `do .. while' statement), and C++ functions with
1585 reference parameters are recognized. The modes require font-lock mode
1586 to be enabled.
1587
1588 +++
1589 *** smerge-mode.el provides `smerge-mode', a simple minor-mode for files
1590 containing diff3-style conflict markers, such as generated by RCS.
1591
1592 +++
1593 *** 5x5.el is a simple puzzle game.
1594
1595 +++
1596 *** hl-line.el provides a minor mode to highlight the current line.
1597
1598 *** ansi-color.el translates ANSI terminal escapes into text-properties.
1599
1600 Please note: if `ansi-color-for-shell-mode' and
1601 `global-font-lock-mode' are non-nil, loading ansi-color.el will
1602 disable font-lock and add `ansi-color-apply' to
1603 `comint-preoutput-filter-functions' for all shell-mode buffers. This
1604 displays the output of "ls --color=yes" using the correct foreground
1605 and background colors.
1606
1607 *** delphi.el provides a major mode for editing the Delphi (Object
1608 Pascal) language.
1609
1610 +++
1611 *** quickurl.el provides a simple method of inserting a URL based on
1612 the text at point.
1613
1614 *** sql.el provides an interface to SQL data bases.
1615
1616 +++
1617 *** fortune.el uses the fortune program to create mail/news signatures.
1618
1619 *** whitespace.el ???
1620
1621 *** PostScript mode (ps-mode) is a new major mode for editing PostScript
1622 files. It offers: interaction with a PostScript interpreter, including
1623 (very basic) error handling; fontification, easily customizable for
1624 interpreter messages; auto-indentation; insertion of EPSF templates and
1625 often used code snippets; viewing of BoundingBox; commenting out /
1626 uncommenting regions; conversion of 8bit characters to PostScript octal
1627 codes. All functionality is accessible through a menu.
1628
1629 *** delim-col helps to prettify columns in a text region or rectangle.
1630
1631 Here is an example of columns:
1632
1633 horse apple bus
1634 dog pineapple car EXTRA
1635 porcupine strawberry airplane
1636
1637 Doing the following settings:
1638
1639 (setq delimit-columns-str-before "[ ")
1640 (setq delimit-columns-str-after " ]")
1641 (setq delimit-columns-str-separator ", ")
1642 (setq delimit-columns-separator "\t")
1643
1644
1645 Selecting the lines above and typing:
1646
1647 M-x delimit-columns-region
1648
1649 It results:
1650
1651 [ horse , apple , bus , ]
1652 [ dog , pineapple , car , EXTRA ]
1653 [ porcupine, strawberry, airplane, ]
1654
1655 delim-col has the following options:
1656
1657 delimit-columns-str-before Specify a string to be inserted
1658 before all columns.
1659
1660 delimit-columns-str-separator Specify a string to be inserted
1661 between each column.
1662
1663 delimit-columns-str-after Specify a string to be inserted
1664 after all columns.
1665
1666 delimit-columns-separator Specify a regexp which separates
1667 each column.
1668
1669 delim-col has the following commands:
1670
1671 delimit-columns-region Prettify all columns in a text region.
1672 delimit-columns-rectangle Prettify all columns in a text rectangle.
1673
1674 +++
1675 *** The package recentf.el maintains a menu for visiting files that
1676 were operated on recently.
1677
1678 M-x recentf-mode RET toggles recentf mode.
1679
1680 M-x customize-variable RET recentf-mode RET can be used to enable
1681 recentf at Emacs startup.
1682
1683 M-x customize-variable RET recentf-menu-filter RET to specify a menu
1684 filter function to change the menu appearance. For example, the recent
1685 file list can be displayed:
1686
1687 - organized by major modes, directories or user defined rules.
1688 - sorted by file pathes, file names, ascending or descending.
1689 - showing pathes relative to the current default-directory
1690
1691 The `recentf-filter-changer' menu filter function allows to
1692 dynamically change the menu appearance.
1693
1694 *** elide-head.el provides a mechanism for eliding boilerplate header
1695 text.
1696
1697 +++
1698 *** footnote.el provides `footnote-mode', a minor mode supporting use
1699 of footnotes. It is intended for use with Message mode, but isn't
1700 specific to Message mode.
1701
1702 +++
1703 *** diff-mode.el provides `diff-mode', a major mode for
1704 viewing/editing context diffs (patches). It is selected for files
1705 with extension `.diff', `.diffs', `.patch' and `.rej'.
1706
1707 +++
1708 *** EUDC, the Emacs Unified Directory Client, provides a common user
1709 interface to access directory servers using different directory
1710 protocols. It has a separate manual.
1711
1712 *** autoconf.el provides a major mode for editing configure.in files
1713 for Autoconf, selected automatically.
1714
1715 +++
1716 *** windmove.el provides moving between windows.
1717
1718 *** crm.el provides a facility to read multiple strings from the
1719 minibuffer with completion.
1720
1721 *** todo-mode.el provides management of TODO lists and integration
1722 with the diary features.
1723
1724 *** autoarg.el provides a feature reported from Twenex Emacs whereby
1725 numeric keys supply prefix args rather than self inserting.
1726
1727 *** The function `turn-off-auto-fill' unconditionally turns off Auto
1728 Fill mode.
1729
1730 *** gnus-mule.el is now just a compatibility layer over the built-in
1731 Gnus facilities.
1732
1733 ** Withdrawn packages
1734
1735 *** mldrag.el has been removed. mouse.el provides the same
1736 functionality with aliases for the mldrag functions.
1737
1738 *** eval-reg.el has been obsoleted by changes to edebug.el and removed.
1739
1740 *** ph.el has been obsoleted by EUDC and removed.
1741
1742 \f
1743 * Lisp changes made after edition 2.6 of the Emacs Lisp Manual,
1744 (Display-related features are described in a page of their own below.)
1745
1746 +++
1747 ** The new function `display-message-or-buffer' displays a message in
1748 the echo area or pops up a buffer, depending on the length of the
1749 message.
1750
1751 ** The new macro `with-auto-compression-mode' allows evaluating an
1752 expression with auto-compression-mode enabled.
1753
1754 ** In image specifications, `:heuristic-mask' has been replaced
1755 with the more general `:mask' property.
1756
1757 ** Image specifications accept more `:algorithm's.
1758
1759 ** A `?' can be used in a symbol name without escaping it with a
1760 backslash.
1761
1762 +++
1763 ** Reading from the mini-buffer now reads from standard input if Emacs
1764 is running in batch mode. For example,
1765
1766 (message "%s" (read t))
1767
1768 will read a Lisp expression from standard input and print the result
1769 to standard output.
1770
1771 +++
1772 ** The argument of `down-list', `backward-up-list', `up-list',
1773 `kill-sexp', `backward-kill-sexp' and `mark-sexp' is now optional.
1774
1775 ** If `display-buffer-reuse-frames' is set, function `display-buffer'
1776 will raise frames displaying a buffer, instead of creating a new
1777 frame or window.
1778
1779 +++
1780 ** Two new functions for removing elements from lists/sequences
1781 were added
1782
1783 - Function: remove ELT SEQ
1784
1785 Return a copy of SEQ with all occurences of ELT removed. SEQ must be
1786 a list, vector, or string. The comparison is done with `equal'.
1787
1788 - Function: remq ELT LIST
1789
1790 Return a copy of LIST with all occurences of ELT removed. The
1791 comparison is done with `eq'.
1792
1793 ** The function `delete' now also works with vectors and strings.
1794
1795 ** The meaning of the `:weakness WEAK' argument of make-hash-table
1796 has been changed.
1797
1798 +++
1799 ** Function `aset' stores any multibyte character in any string
1800 without signaling "Attempt to change char length of a string". It may
1801 convert a unibyte string to multibyte if necessary.
1802
1803 ** The value of the `help-echo' text property is called as a function
1804 or evaluated, if it is not a string already, to obtain a help string.
1805
1806 ** Function `make-obsolete' now has an optional arg to say when the
1807 function was declared obsolete.
1808
1809 ** Function `plist-member' is renamed from `widget-plist-member' (which is
1810 retained as an alias).
1811
1812 ** Easy-menu's :filter now works as in XEmacs.
1813 It takes the unconverted (i.e. XEmacs) form of the menu and the result
1814 is automatically converted to Emacs' form.
1815
1816 ** The new function `window-list' has been defined
1817
1818 - Function: window-list &optional WINDOW MINIBUF ALL-FRAMES
1819
1820 Return a list of windows in canonical order. The parameters WINDOW,
1821 MINIBUF and ALL-FRAMES are defined like for `next-window'.
1822
1823 ** There's a new function `some-window' defined as follows
1824
1825 - Function: some-window PREDICATE &optional MINIBUF ALL-FRAMES DEFAULT
1826
1827 Return a window satisfying PREDICATE.
1828
1829 This function cycles through all visible windows using `walk-windows',
1830 calling PREDICATE on each one. PREDICATE is called with a window as
1831 argument. The first window for which PREDICATE returns a non-nil
1832 value is returned. If no window satisfies PREDICATE, DEFAULT is
1833 returned.
1834
1835 Optional second arg MINIBUF t means count the minibuffer window even
1836 if not active. MINIBUF nil or omitted means count the minibuffer iff
1837 it is active. MINIBUF neither t nor nil means not to count the
1838 minibuffer even if it is active.
1839
1840 Several frames may share a single minibuffer; if the minibuffer
1841 counts, all windows on all frames that share that minibuffer count
1842 too. Therefore, if you are using a separate minibuffer frame
1843 and the minibuffer is active and MINIBUF says it counts,
1844 `walk-windows' includes the windows in the frame from which you
1845 entered the minibuffer, as well as the minibuffer window.
1846
1847 ALL-FRAMES is the optional third argument.
1848 ALL-FRAMES nil or omitted means cycle within the frames as specified above.
1849 ALL-FRAMES = `visible' means include windows on all visible frames.
1850 ALL-FRAMES = 0 means include windows on all visible and iconified frames.
1851 ALL-FRAMES = t means include windows on all frames including invisible frames.
1852 If ALL-FRAMES is a frame, it means include windows on that frame.
1853 Anything else means restrict to the selected frame.
1854
1855 ** The function `single-key-description' now encloses function key and
1856 event names in angle brackets. When called with a second optional
1857 argument non-nil, angle brackets won't be printed.
1858
1859 ** If the variable `message-truncate-lines' is bound to t around a
1860 call to `message', the echo area will not be resized to display that
1861 message; it will be truncated instead, as it was done in 20.x.
1862 Default value is nil.
1863
1864 ** The user option `line-number-display-limit' can now be set to nil,
1865 meaning no limit.
1866
1867 ** `select-safe-coding-system' now also checks the most preferred
1868 coding-system if buffer-file-coding-system is `undecided' and
1869 DEFAULT-CODING-SYSTEM is not specified,
1870
1871 ** The function `subr-arity' provides information on the argument list
1872 of a primitive.
1873
1874 ** The text property `keymap' specifies a key map which overrides the
1875 buffer's local map and the map specified by the `local-map' property.
1876 This is probably what most current uses of `local-map' want, rather
1877 than replacing the local map.
1878
1879 ** The obsolete variables before-change-function and
1880 after-change-function are no longer acted upon and have been removed.
1881
1882 ** The function `apropos-mode' runs the hook `apropos-mode-hook'.
1883
1884 +++
1885 ** `concat' no longer accepts individual integer arguments, as
1886 promised long ago.
1887
1888 ** The new function `float-time' returns the current time as a float.
1889 \f
1890 * Lisp changes in Emacs 21.1 (see following page for display-related features)
1891
1892 Note that +++ before an item means the Lisp manual has been updated.
1893 --- means that I have decided it does not need to be in the Lisp manual.
1894 When you add a new item, please add it without either +++ or ---
1895 so I will know I still need to look at it -- rms.
1896
1897 *** The special form `save-restriction' now works correctly even if the
1898 buffer is widened inside the save-restriction and changes made outside
1899 the original restriction. Previously, doing this would cause the saved
1900 restriction to be restored incorrectly.
1901
1902 *** The functions `find-charset-region' and `find-charset-string' include
1903 `eight-bit-control' and/or `eight-bit-graphic' in the returned list
1904 when it finds 8-bit characters. Previously, it included `ascii' in a
1905 multibyte buffer and `unknown' in a unibyte buffer.
1906
1907 *** The functions `set-buffer-modified', `string-as-multibyte' and
1908 `string-as-unibyte' change the byte sequence of a buffer if it
1909 contains a character from the `eight-bit-control' character set.
1910
1911 *** The handling of multibyte sequences in a multibyte buffer is
1912 changed. Previously, a byte sequence matching the pattern
1913 [\200-\237][\240-\377]+ was interpreted as a single character
1914 regardless of the length of the trailing bytes [\240-\377]+. Thus, if
1915 the sequence was longer than what the leading byte indicated, the
1916 extra trailing bytes were ignored by Lisp functions. Now such extra
1917 bytes are independent 8-bit characters belonging to the charset
1918 eight-bit-graphic.
1919
1920 ** Fontsets are now implemented using char-tables.
1921
1922 A fontset can now be specified for for each independent character, for
1923 a group of characters or for a character set rather than just for a
1924 character set as previously.
1925
1926 *** The arguments of the function `set-fontset-font' are changed.
1927 They are NAME, CHARACTER, FONTNAME, and optional FRAME. The function
1928 modifies fontset NAME to use FONTNAME for CHARACTER.
1929
1930 CHARACTER may be a cons (FROM . TO), where FROM and TO are non-generic
1931 characters. In that case FONTNAME is used for all characters in the
1932 range FROM and TO (inclusive). CHARACTER may be a charset. In that
1933 case FONTNAME is used for all character in the charset.
1934
1935 FONTNAME may be a cons (FAMILY . REGISTRY), where FAMILY is the family
1936 name of a font and REGSITRY is a registry name of a font.
1937
1938 *** Variable x-charset-registry has been deleted. The default charset
1939 registries of character sets are set in the default fontset
1940 "fontset-default".
1941
1942 *** The function `create-fontset-from-fontset-spec' ignores the second
1943 argument STYLE-VARIANT. It never creates style-variant fontsets.
1944
1945 ** The method of composing characters is changed. Now character
1946 composition is done by a special text property `composition' in
1947 buffers and strings.
1948
1949 *** Charset composition is deleted. Emacs never creates a `composite
1950 character' which is an independent character with a unique character
1951 code. Thus the following functions handling `composite characters'
1952 have been deleted: composite-char-component,
1953 composite-char-component-count, composite-char-composition-rule,
1954 composite-char-composition-rule and decompose-composite-char delete.
1955 The variables leading-code-composition and min-composite-char have
1956 also been deleted.
1957
1958 *** Three more glyph reference points are added. They can be used to
1959 specify a composition rule. See the documentation of the variable
1960 `reference-point-alist' for more detail.
1961
1962 *** The function `compose-region' takes new arguments COMPONENTS and
1963 MODIFICATION-FUNC. With COMPONENTS, you can specify not only a
1964 composition rule but also characters to be composed. Such characters
1965 may differ between buffer and string text.
1966
1967 *** The function `compose-string' takes new arguments START, END,
1968 COMPONENTS, and MODIFICATION-FUNC.
1969
1970 *** The function `compose-string' puts text property `composition'
1971 directly on the argument STRING instead of returning a new string.
1972 Likewise, the function `decompose-string' just removes text property
1973 `composition' from STRING.
1974
1975 *** The new function `find-composition' returns information about
1976 a composition at a specified position in a buffer or a string.
1977
1978 *** The function `decompose-composite-char' is now labeled as
1979 obsolete.
1980
1981 ** The new character set `mule-unicode-0100-24ff' is introduced for
1982 Unicode characters of the range U+0100..U+24FF. Currently, this
1983 character set is not used.
1984
1985 ** The new character sets `japanese-jisx0213-1' and
1986 `japanese-jisx0213-2' are introduced for the new Japanese standard JIS
1987 X 0213 Plane 1 and Plane 2.
1988
1989 +++
1990 ** The new character sets `eight-bit-control' and `eight-bit-graphic'
1991 are introduced for 8-bit characters in the ranges 0x80..0x9F and
1992 0xA0..0xFF respectively.
1993
1994 +++
1995 ** If the APPEND argument of `write-region' is an integer, it seeks to
1996 that offset in the file before writing.
1997
1998 ** The function `add-minor-mode' has been added for convenience and
1999 compatibility with XEmacs (and is used internally by define-minor-mode).
2000
2001 ** The function `shell-command' now sets the default directory of the
2002 `*Shell Command Output*' buffer to the default directory of the buffer
2003 from which the command was issued.
2004
2005 ** The functions `query-replace', `query-replace-regexp',
2006 `query-replace-regexp-eval' `map-query-replace-regexp',
2007 `replace-string', `replace-regexp', and `perform-replace' take two
2008 additional optional arguments START and END that specify the region to
2009 operate on.
2010
2011 ** The new function `count-screen-lines' is a more flexible alternative
2012 to `window-buffer-height'.
2013
2014 - Function: count-screen-lines &optional BEG END COUNT-FINAL-NEWLINE WINDOW
2015
2016 Return the number of screen lines in the region between BEG and END.
2017 The number of screen lines may be different from the number of actual
2018 lines, due to line breaking, display table, etc.
2019
2020 Optional arguments BEG and END default to `point-min' and `point-max'
2021 respectively.
2022
2023 If region ends with a newline, ignore it unless optinal third argument
2024 COUNT-FINAL-NEWLINE is non-nil.
2025
2026 The optional fourth argument WINDOW specifies the window used for
2027 obtaining parameters such as width, horizontal scrolling, and so
2028 on. The default is to use the selected window's parameters.
2029
2030 Like `vertical-motion', `count-screen-lines' always uses the current
2031 buffer, regardless of which buffer is displayed in WINDOW. This makes
2032 possible to use `count-screen-lines' in any buffer, whether or not it
2033 is currently displayed in some window.
2034
2035 ** The new function `mapc' is like `mapcar' but doesn't collect the
2036 argument function's results.
2037
2038 ** The functions base64-decode-region and base64-decode-string now
2039 signal an error instead of returning nil if decoding fails.
2040
2041 ** The function sendmail-user-agent-compose now recognizes a `body'
2042 header in the list of headers passed to it.
2043
2044 ** The new function member-ignore-case works like `member', but
2045 ignores differences in case and text representation.
2046
2047 ** The buffer-local variable cursor-type can be used to specify the
2048 cursor to use in windows displaying a buffer. Values are interpreted
2049 as follows:
2050
2051 t use the cursor specified for the frame (default)
2052 nil don't display a cursor
2053 `bar' display a bar cursor with default width
2054 (bar . WIDTH) display a bar cursor with width WIDTH
2055 others display a box cursor.
2056
2057 ** The variable open-paren-in-column-0-is-defun-start controls whether
2058 an open parenthesis in column 0 is considered to be the start of a
2059 defun. If set, the default, it is considered a defun start. If not
2060 set, an open parenthesis in column 0 has no special meaning.
2061
2062 ** The new function `string-to-syntax' can be used to translate syntax
2063 specifications in string form as accepted by `modify-syntax-entry' to
2064 the cons-cell form that is used for the values of the `syntax-table'
2065 text property, and in `font-lock-syntactic-keywords'.
2066
2067 Example:
2068
2069 (string-to-syntax "()")
2070 => (4 . 41)
2071
2072 ** Emacs' reader supports CL read syntax for integers in bases
2073 other than 10.
2074
2075 *** `#BINTEGER' or `#bINTEGER' reads INTEGER in binary (radix 2).
2076 INTEGER optionally contains a sign.
2077
2078 #b1111
2079 => 15
2080 #b-1111
2081 => -15
2082
2083 *** `#OINTEGER' or `#oINTEGER' reads INTEGER in octal (radix 8).
2084
2085 #o666
2086 => 438
2087
2088 *** `#XINTEGER' or `#xINTEGER' reads INTEGER in hexadecimal (radix 16).
2089
2090 #xbeef
2091 => 48815
2092
2093 *** `#RADIXrINTEGER' reads INTEGER in radix RADIX, 2 <= RADIX <= 36.
2094
2095 #2R-111
2096 => -7
2097 #25rah
2098 => 267
2099
2100 ** The function `documentation-property' now evaluates the value of
2101 the given property to obtain a string if it doesn't refer to etc/DOC
2102 and isn't a string.
2103
2104 ** If called for a symbol, the function `documentation' now looks for
2105 a `function-documentation' property of that symbol. If it has a non-nil
2106 value, the documentation is taken from that value. If the value is
2107 not a string, it is evaluated to obtain a string.
2108
2109 +++
2110 ** The last argument of `define-key-after' defaults to t for convenience.
2111
2112 ** The new function `replace-regexp-in-string' replaces all matches
2113 for a regexp in a string.
2114
2115 ** `mouse-position' now runs the abnormal hook
2116 `mouse-position-function'.
2117
2118 ** The function string-to-number now returns a float for numbers
2119 that don't fit into a Lisp integer.
2120
2121 ** The variable keyword-symbols-constants-flag has been removed.
2122 Keywords are now always considered constants.
2123
2124 +++
2125 ** The new function `delete-and-extract-region' deletes text and
2126 returns it.
2127
2128 ** The function `clear-this-command-keys' now also clears the vector
2129 returned by function `recent-keys'.
2130
2131 +++
2132 ** Variables `beginning-of-defun-function' and `end-of-defun-function'
2133 can be used to define handlers for the functions that find defuns.
2134 Major modes can define these locally instead of rebinding M-C-a
2135 etc. if the normal conventions for defuns are not appropriate for the
2136 mode.
2137
2138 +++
2139 ** easy-mmode-define-minor-mode now takes an additional BODY argument
2140 and is renamed `define-minor-mode'.
2141
2142 +++
2143 ** If an abbrev has a hook function which is a symbol, and that symbol
2144 has a non-nil `no-self-insert' property, the return value of the hook
2145 function specifies whether an expansion has been done or not. If it
2146 returns nil, abbrev-expand also returns nil, meaning "no expansion has
2147 been performed."
2148
2149 When abbrev expansion is done by typing a self-inserting character,
2150 and the abbrev has a hook with the `no-self-insert' property, and the
2151 hook function returns non-nil meaning expansion has been done,
2152 then the self-inserting character is not inserted.
2153
2154 +++
2155 ** The function `intern-soft' now accepts a symbol as first argument.
2156 In this case, that exact symbol is looked up in the specified obarray,
2157 and the function's value is nil if it is not found.
2158
2159 +++
2160 ** The new macro `with-syntax-table' can be used to evaluate forms
2161 with the syntax table of the current buffer temporarily set to a
2162 specified table.
2163
2164 (with-syntax-table TABLE &rest BODY)
2165
2166 Evaluate BODY with syntax table of current buffer set to a copy of
2167 TABLE. The current syntax table is saved, BODY is evaluated, and the
2168 saved table is restored, even in case of an abnormal exit. Value is
2169 what BODY returns.
2170
2171 +++
2172 ** Regular expressions now support intervals \{n,m\} as well as
2173 Perl's shy-groups \(?:...\) and non-greedy *? +? and ?? operators.
2174
2175 +++
2176 ** The optional argument BUFFER of function file-local-copy has been
2177 removed since it wasn't used by anything.
2178
2179 +++
2180 ** The file name argument of function `file-locked-p' is now required
2181 instead of being optional.
2182
2183 +++
2184 ** The new built-in error `text-read-only' is signaled when trying to
2185 modify read-only text.
2186
2187 +++
2188 ** New functions and variables for locales.
2189
2190 The new variable `locale-coding-system' specifies how to encode and
2191 decode strings passed to low-level message functions like strerror and
2192 time functions like strftime. The new variables
2193 `system-messages-locale' and `system-time-locale' give the system
2194 locales to be used when invoking these two types of functions.
2195
2196 The new function `set-locale-environment' sets the language
2197 environment, preferred coding system, and locale coding system from
2198 the system locale as specified by the LC_ALL, LC_CTYPE, and LANG
2199 environment variables. Normally, it is invoked during startup and need
2200 not be invoked thereafter. It uses the new variables
2201 `locale-language-names', `locale-charset-language-names', and
2202 `locale-preferred-coding-systems' to make its decisions.
2203
2204 +++
2205 ** syntax tables now understand nested comments.
2206 To declare a comment syntax as allowing nesting, just add an `n'
2207 modifier to either of the characters of the comment end and the comment
2208 start sequences.
2209
2210 +++
2211 ** The function `pixmap-spec-p' has been renamed `bitmap-spec-p'
2212 because `bitmap' is more in line with the usual X terminology.
2213
2214 +++
2215 ** New function `propertize'
2216
2217 The new function `propertize' can be used to conveniently construct
2218 strings with text properties.
2219
2220 - Function: propertize STRING &rest PROPERTIES
2221
2222 Value is a copy of STRING with text properties assigned as specified
2223 by PROPERTIES. PROPERTIES is a sequence of pairs PROPERTY VALUE, with
2224 PROPERTY being the name of a text property and VALUE being the
2225 specified value of that property. Example:
2226
2227 (propertize "foo" 'face 'bold 'read-only t)
2228
2229 +++
2230 ** push and pop macros.
2231
2232 Simple versions of the push and pop macros of Common Lisp
2233 are now defined in Emacs Lisp. These macros allow only symbols
2234 as the place that holds the list to be changed.
2235
2236 (push NEWELT LISTNAME) add NEWELT to the front of LISTNAME's value.
2237 (pop LISTNAME) return first elt of LISTNAME, and remove it
2238 (thus altering the value of LISTNAME).
2239
2240 ** New dolist and dotimes macros.
2241
2242 Simple versions of the dolist and dotimes macros of Common Lisp
2243 are now defined in Emacs Lisp.
2244
2245 (dolist (VAR LIST [RESULT]) BODY...)
2246 Execute body once for each element of LIST,
2247 using the variable VAR to hold the current element.
2248 Then return the value of RESULT, or nil if RESULT is omitted.
2249
2250 (dotimes (VAR COUNT [RESULT]) BODY...)
2251 Execute BODY with VAR bound to successive integers running from 0,
2252 inclusive, to COUNT, exclusive.
2253 Then return the value of RESULT, or nil if RESULT is omitted.
2254
2255 +++
2256 ** Regular expressions now support Posix character classes such
2257 as [:alpha:], [:space:] and so on.
2258
2259 [:digit:] matches 0 through 9
2260 [:cntrl:] matches ASCII control characters
2261 [:xdigit:] matches 0 through 9, a through f and A through F.
2262 [:blank:] matches space and tab only
2263 [:graph:] matches graphic characters--everything except ASCII control chars,
2264 space, and DEL.
2265 [:print:] matches printing characters--everything except ASCII control chars
2266 and DEL.
2267 [:alnum:] matches letters and digits.
2268 (But at present, for multibyte characters,
2269 it matches anything that has word syntax.)
2270 [:alpha:] matches letters.
2271 (But at present, for multibyte characters,
2272 it matches anything that has word syntax.)
2273 [:ascii:] matches ASCII (unibyte) characters.
2274 [:nonascii:] matches non-ASCII (multibyte) characters.
2275 [:lower:] matches anything lower-case.
2276 [:punct:] matches punctuation.
2277 (But at present, for multibyte characters,
2278 it matches anything that has non-word syntax.)
2279 [:space:] matches anything that has whitespace syntax.
2280 [:upper:] matches anything upper-case.
2281 [:word:] matches anything that has word syntax.
2282
2283 +++
2284 ** Emacs now has built-in hash tables.
2285
2286 The following functions are defined for hash tables:
2287
2288 - Function: make-hash-table ARGS
2289
2290 The argument list ARGS consists of keyword/argument pairs. All arguments
2291 are optional. The following arguments are defined:
2292
2293 :test TEST
2294
2295 TEST must be a symbol specifying how to compare keys. Default is `eql'.
2296 Predefined are `eq', `eql' and `equal'. If TEST is not predefined,
2297 it must have been defined with `define-hash-table-test'.
2298
2299 :size SIZE
2300
2301 SIZE must be an integer > 0 giving a hint to the implementation how
2302 many elements will be put in the hash table. Default size is 65.
2303
2304 :rehash-size REHASH-SIZE
2305
2306 REHASH-SIZE specifies by how much to grow a hash table once it becomes
2307 full. If REHASH-SIZE is an integer, add that to the hash table's old
2308 size to get the new size. Otherwise, REHASH-SIZE must be a float >
2309 1.0, and the new size is computed by multiplying REHASH-SIZE with the
2310 old size. Default rehash size is 1.5.
2311
2312 :rehash-threshold THRESHOLD
2313
2314 THRESHOLD must be a float > 0 and <= 1.0 specifying when to resize the
2315 hash table. It is resized when the ratio of (number of entries) /
2316 (size of hash table) is >= THRESHOLD. Default threshold is 0.8.
2317
2318 :weakness WEAK
2319
2320 WEAK must be either nil, one of the symbols `key, `value',
2321 `key-or-value', `key-and-value', or t, meaning the same as
2322 `key-and-value'. Entries are removed from weak tables during garbage
2323 collection if their key and/or value are not referenced elsewhere
2324 outside of the hash table. Default are non-weak hash tables.
2325
2326 - Function: makehash &optional TEST
2327
2328 Similar to make-hash-table, but only TEST can be specified.
2329
2330 - Function: hash-table-p TABLE
2331
2332 Returns non-nil if TABLE is a hash table object.
2333
2334 - Function: copy-hash-table TABLE
2335
2336 Returns a copy of TABLE. Only the table itself is copied, keys and
2337 values are shared.
2338
2339 - Function: hash-table-count TABLE
2340
2341 Returns the number of entries in TABLE.
2342
2343 - Function: hash-table-rehash-size TABLE
2344
2345 Returns the rehash size of TABLE.
2346
2347 - Function: hash-table-rehash-threshold TABLE
2348
2349 Returns the rehash threshold of TABLE.
2350
2351 - Function: hash-table-rehash-size TABLE
2352
2353 Returns the size of TABLE.
2354
2355 - Function: hash-table-test TABLE
2356
2357 Returns the test TABLE uses to compare keys.
2358
2359 - Function: hash-table-weakness TABLE
2360
2361 Returns the weakness specified for TABLE.
2362
2363 - Function: clrhash TABLE
2364
2365 Clear TABLE.
2366
2367 - Function: gethash KEY TABLE &optional DEFAULT
2368
2369 Look up KEY in TABLE and return its associated VALUE or DEFAULT if
2370 not found.
2371
2372 - Function: puthash KEY VALUE TABLE
2373
2374 Associate KEY with VALUE in TABLE. If KEY is already associated with
2375 another value, replace the old value with VALUE.
2376
2377 - Function: remhash KEY TABLE
2378
2379 Remove KEY from TABLE if it is there.
2380
2381 - Function: maphash FUNCTION TABLE
2382
2383 Call FUNCTION for all elements in TABLE. FUNCTION must take two
2384 arguments KEY and VALUE.
2385
2386 - Function: sxhash OBJ
2387
2388 Return a hash code for Lisp object OBJ.
2389
2390 - Function: define-hash-table-test NAME TEST-FN HASH-FN
2391
2392 Define a new hash table test named NAME. If NAME is specified as
2393 a test in `make-hash-table', the table created will use TEST-FN for
2394 comparing keys, and HASH-FN to compute hash codes for keys. Test
2395 and hash function are stored as symbol property `hash-table-test'
2396 of NAME with a value of (TEST-FN HASH-FN).
2397
2398 TEST-FN must take two arguments and return non-nil if they are the same.
2399
2400 HASH-FN must take one argument and return an integer that is the hash
2401 code of the argument. The function should use the whole range of
2402 integer values for hash code computation, including negative integers.
2403
2404 Example: The following creates a hash table whose keys are supposed to
2405 be strings that are compared case-insensitively.
2406
2407 (defun case-fold-string= (a b)
2408 (compare-strings a nil nil b nil nil t))
2409
2410 (defun case-fold-string-hash (a)
2411 (sxhash (upcase a)))
2412
2413 (define-hash-table-test 'case-fold 'case-fold-string=
2414 'case-fold-string-hash))
2415
2416 (make-hash-table :test 'case-fold)
2417
2418 +++
2419 ** The Lisp reader handles circular structure.
2420
2421 It now works to use the #N= and #N# constructs to represent
2422 circular structures. For example, #1=(a . #1#) represents
2423 a cons cell which is its own cdr.
2424
2425 +++
2426 ** The Lisp printer handles circular structure.
2427
2428 If you bind print-circle to a non-nil value, the Lisp printer outputs
2429 #N= and #N# constructs to represent circular and shared structure.
2430
2431 +++
2432 ** If the second argument to `move-to-column' is anything but nil or
2433 t, that means replace a tab with spaces if necessary to reach the
2434 specified column, but do not add spaces at the end of the line if it
2435 is too short to reach that column.
2436
2437 +++
2438 ** perform-replace has a new feature: the REPLACEMENTS argument may
2439 now be a cons cell (FUNCTION . DATA). This means to call FUNCTION
2440 after each match to get the replacement text. FUNCTION is called with
2441 two arguments: DATA, and the number of replacements already made.
2442
2443 If the FROM-STRING contains any upper-case letters,
2444 perform-replace also turns off `case-fold-search' temporarily
2445 and inserts the replacement text without altering case in it.
2446
2447 +++
2448 ** The function buffer-size now accepts an optional argument
2449 to specify which buffer to return the size of.
2450
2451 +++
2452 ** The calendar motion commands now run the normal hook
2453 calendar-move-hook after moving point.
2454
2455 +++
2456 ** The new variable small-temporary-file-directory specifies a
2457 directory to use for creating temporary files that are likely to be
2458 small. (Certain Emacs features use this directory.) If
2459 small-temporary-file-directory is nil, they use
2460 temporary-file-directory instead.
2461
2462 +++
2463 ** The variable `inhibit-modification-hooks', if non-nil, inhibits all
2464 the hooks that track changes in the buffer. This affects
2465 `before-change-functions' and `after-change-functions', as well as
2466 hooks attached to text properties and overlay properties.
2467
2468 +++
2469 ** assoc-delete-all is a new function that deletes all the
2470 elements of an alist which have a particular value as the car.
2471
2472 +++
2473 ** make-temp-file provides a more reliable way to create a temporary file.
2474
2475 make-temp-file is used like make-temp-name, except that it actually
2476 creates the file before it returns. This prevents a timing error,
2477 ensuring that no other job can use the same name for a temporary file.
2478
2479 +++
2480 ** New exclusive-open feature in `write-region'
2481
2482 The optional seventh arg is now called MUSTBENEW. If non-nil, it insists
2483 on a check for an existing file with the same name. If MUSTBENEW
2484 is `excl', that means to get an error if the file already exists;
2485 never overwrite. If MUSTBENEW is neither nil nor `excl', that means
2486 ask for confirmation before overwriting, but do go ahead and
2487 overwrite the file if the user gives confirmation.
2488
2489 If the MUSTBENEW argument in `write-region' is `excl',
2490 that means to use a special feature in the `open' system call
2491 to get an error if the file exists at that time.
2492 The error reported is `file-already-exists'.
2493
2494 +++
2495 ** Function `format' now handles text properties.
2496
2497 Text properties of the format string are applied to the result string.
2498 If the result string is longer than the format string, text properties
2499 ending at the end of the format string are extended to the end of the
2500 result string.
2501
2502 Text properties from string arguments are applied to the result
2503 string where arguments appear in the result string.
2504
2505 Example:
2506
2507 (let ((s1 "hello, %s")
2508 (s2 "world"))
2509 (put-text-property 0 (length s1) 'face 'bold s1)
2510 (put-text-property 0 (length s2) 'face 'italic s2)
2511 (format s1 s2))
2512
2513 results in a bold-face string with an italic `world' at the end.
2514
2515 +++
2516 ** Messages can now be displayed with text properties.
2517
2518 Text properties are handled as described above for function `format'.
2519 The following example displays a bold-face message with an italic
2520 argument in it.
2521
2522 (let ((msg "hello, %s!")
2523 (arg "world"))
2524 (put-text-property 0 (length msg) 'face 'bold msg)
2525 (put-text-property 0 (length arg) 'face 'italic arg)
2526 (message msg arg))
2527
2528 +++
2529 ** Sound support
2530
2531 Emacs supports playing sound files on GNU/Linux and the free BSDs
2532 (Voxware driver and native BSD driver, aka as Luigi's driver).
2533
2534 Currently supported file formats are RIFF-WAVE (*.wav) and Sun Audio
2535 (*.au). You must configure Emacs with the option `--with-sound=yes'
2536 to enable sound support.
2537
2538 Sound files can be played by calling (play-sound SOUND). SOUND is a
2539 list of the form `(sound PROPERTY...)'. The function is only defined
2540 when sound support is present for the system on which Emacs runs. The
2541 functions runs `play-sound-functions' with one argument which is the
2542 sound to play, before playing the sound.
2543
2544 The following sound properties are supported:
2545
2546 - `:file FILE'
2547
2548 FILE is a file name. If FILE isn't an absolute name, it will be
2549 searched relative to `data-directory'.
2550
2551 - `:data DATA'
2552
2553 DATA is a string containing sound data. Either :file or :data
2554 may be present, but not both.
2555
2556 - `:volume VOLUME'
2557
2558 VOLUME must be an integer in the range 0..100 or a float in the range
2559 0..1. This property is optional.
2560
2561 Other properties are ignored.
2562
2563 ** `multimedia' is a new Finder keyword and Custom group.
2564
2565 ** keywordp is a new predicate to test efficiently for an object being
2566 a keyword symbol.
2567
2568 ** Changes to garbage collection
2569
2570 *** The function garbage-collect now additionally returns the number
2571 of live and free strings.
2572
2573 *** There is a new variable `strings-consed' holding the number of
2574 strings that have been consed so far.
2575
2576 \f
2577 * Lisp-level Display features added after release 2.6 of the Emacs
2578 Lisp Manual
2579
2580 *** On window systems, `glyph-table' is no longer used.
2581
2582 +++
2583 ** Help strings in menu items are now used to provide `help-echo' text.
2584
2585 ** The function `image-size' can be used to determine the size of an
2586 image.
2587
2588 - Function: image-size SPEC &optional PIXELS FRAME
2589
2590 Return the size of an image as a pair (WIDTH . HEIGHT).
2591
2592 SPEC is an image specification. PIXELS non-nil means return sizes
2593 measured in pixels, otherwise return sizes measured in canonical
2594 character units (fractions of the width/height of the frame's default
2595 font). FRAME is the frame on which the image will be displayed.
2596 FRAME nil or omitted means use the selected frame.
2597
2598 ** The function `image-mask-p' can be used to determine if an image
2599 has a mask bitmap.
2600
2601 - Function: image-mask-p SPEC &optional FRAME
2602
2603 Return t if image SPEC has a mask bitmap.
2604 FRAME is the frame on which the image will be displayed. FRAME nil
2605 or omitted means use the selected frame.
2606
2607 +++
2608 ** The function `find-image' can be used to find a usable image
2609 satisfying one of a list of specifications.
2610
2611 +++
2612 ** The STRING argument of `put-image' and `insert-image' is now
2613 optional.
2614
2615 +++
2616 ** Image specifications may contain the property `:ascent center' (see
2617 below).
2618
2619 \f
2620 * New Lisp-level Display features in Emacs 21.1
2621
2622 Note that +++ before an item means the Lisp manual has been updated.
2623 --- means that I have decided it does not need to be in the Lisp manual.
2624 When you add a new item, please add it without either +++ or ---
2625 so I will know I still need to look at it -- rms.
2626
2627 ** The function tty-suppress-bold-inverse-default-colors can be used
2628 to make Emacs avoid displaying text with bold black foreground on TTYs.
2629
2630 Some terminals, notably PC consoles, emulate bold text by displaying
2631 text in brighter colors. On such a console, a bold black foreground
2632 is displayed in a gray color. If this turns out to be hard to read on
2633 your monitor---the problem occurred with the mode line on
2634 laptops---you can instruct Emacs to ignore the text's boldness, and to
2635 just display it black instead.
2636
2637 This situation can't be detected automatically. You will have to put
2638 a line like
2639
2640 (tty-suppress-bold-inverse-default-colors t)
2641
2642 in your `.emacs'.
2643
2644 ** New face implementation.
2645
2646 Emacs faces have been reimplemented from scratch. They don't use XLFD
2647 font names anymore and face merging now works as expected.
2648
2649 +++
2650 *** New faces.
2651
2652 Each face can specify the following display attributes:
2653
2654 1. Font family or fontset alias name.
2655
2656 2. Relative proportionate width, aka character set width or set
2657 width (swidth), e.g. `semi-compressed'.
2658
2659 3. Font height in 1/10pt
2660
2661 4. Font weight, e.g. `bold'.
2662
2663 5. Font slant, e.g. `italic'.
2664
2665 6. Foreground color.
2666
2667 7. Background color.
2668
2669 8. Whether or not characters should be underlined, and in what color.
2670
2671 9. Whether or not characters should be displayed in inverse video.
2672
2673 10. A background stipple, a bitmap.
2674
2675 11. Whether or not characters should be overlined, and in what color.
2676
2677 12. Whether or not characters should be strike-through, and in what
2678 color.
2679
2680 13. Whether or not a box should be drawn around characters, its
2681 color, the width of the box lines, and 3D appearance.
2682
2683 Faces are frame-local by nature because Emacs allows to define the
2684 same named face (face names are symbols) differently for different
2685 frames. Each frame has an alist of face definitions for all named
2686 faces. The value of a named face in such an alist is a Lisp vector
2687 with the symbol `face' in slot 0, and a slot for each each of the face
2688 attributes mentioned above.
2689
2690 There is also a global face alist `face-new-frame-defaults'. Face
2691 definitions from this list are used to initialize faces of newly
2692 created frames.
2693
2694 A face doesn't have to specify all attributes. Those not specified
2695 have a nil value. Faces specifying all attributes are called
2696 `fully-specified'.
2697
2698 +++
2699 *** Face merging.
2700
2701 The display style of a given character in the text is determined by
2702 combining several faces. This process is called `face merging'. Any
2703 aspect of the display style that isn't specified by overlays or text
2704 properties is taken from the `default' face. Since it is made sure
2705 that the default face is always fully-specified, face merging always
2706 results in a fully-specified face.
2707
2708 +++
2709 *** Face realization.
2710
2711 After all face attributes for a character have been determined by
2712 merging faces of that character, that face is `realized'. The
2713 realization process maps face attributes to what is physically
2714 available on the system where Emacs runs. The result is a `realized
2715 face' in form of an internal structure which is stored in the face
2716 cache of the frame on which it was realized.
2717
2718 Face realization is done in the context of the charset of the
2719 character to display because different fonts and encodings are used
2720 for different charsets. In other words, for characters of different
2721 charsets, different realized faces are needed to display them.
2722
2723 Except for composite characters, faces are always realized for a
2724 specific character set and contain a specific font, even if the face
2725 being realized specifies a fontset. The reason is that the result of
2726 the new font selection stage is better than what can be done with
2727 statically defined font name patterns in fontsets.
2728
2729 In unibyte text, Emacs' charsets aren't applicable; function
2730 `char-charset' reports ASCII for all characters, including those >
2731 0x7f. The X registry and encoding of fonts to use is determined from
2732 the variable `face-default-registry' in this case. The variable is
2733 initialized at Emacs startup time from the font the user specified for
2734 Emacs.
2735
2736 Currently all unibyte text, i.e. all buffers with
2737 `enable-multibyte-characters' nil are displayed with fonts of the same
2738 registry and encoding `face-default-registry'. This is consistent
2739 with the fact that languages can also be set globally, only.
2740
2741 ++++
2742 **** Clearing face caches.
2743
2744 The Lisp function `clear-face-cache' can be called to clear face caches
2745 on all frames. If called with a non-nil argument, it will also unload
2746 unused fonts.
2747
2748 +++
2749 *** Font selection.
2750
2751 Font selection tries to find the best available matching font for a
2752 given (charset, face) combination. This is done slightly differently
2753 for faces specifying a fontset, or a font family name.
2754
2755 If the face specifies a fontset name, that fontset determines a
2756 pattern for fonts of the given charset. If the face specifies a font
2757 family, a font pattern is constructed. Charset symbols have a
2758 property `x-charset-registry' for that purpose that maps a charset to
2759 an XLFD registry and encoding in the font pattern constructed.
2760
2761 Available fonts on the system on which Emacs runs are then matched
2762 against the font pattern. The result of font selection is the best
2763 match for the given face attributes in this font list.
2764
2765 Font selection can be influenced by the user.
2766
2767 The user can specify the relative importance he gives the face
2768 attributes width, height, weight, and slant by setting
2769 face-font-selection-order (faces.el) to a list of face attribute
2770 names. The default is (:width :height :weight :slant), and means
2771 that font selection first tries to find a good match for the font
2772 width specified by a face, then---within fonts with that width---tries
2773 to find a best match for the specified font height, etc.
2774
2775 Setting `face-alternative-font-family-alist' allows the user to
2776 specify alternative font families to try if a family specified by a
2777 face doesn't exist.
2778
2779 +++
2780 **** Scalable fonts
2781
2782 Emacs can make use of scalable fonts but doesn't do so by default,
2783 since the use of too many or too big scalable fonts may crash XFree86
2784 servers.
2785
2786 To enable scalable font use, set the variable
2787 `scalable-fonts-allowed'. A value of nil, the default, means never use
2788 scalable fonts. A value of t means any scalable font may be used.
2789 Otherwise, the value must be a list of regular expressions. A
2790 scalable font may then be used if it matches a regular expression from
2791 that list. Example:
2792
2793 (setq scalable-fonts-allowed '("muleindian-2$"))
2794
2795 allows the use of scalable fonts with registry `muleindian-2'.
2796
2797 +++
2798 *** Functions and variables related to font selection.
2799
2800 - Function: x-family-fonts &optional FAMILY FRAME
2801
2802 Return a list of available fonts of family FAMILY on FRAME. If FAMILY
2803 is omitted or nil, list all families. Otherwise, FAMILY must be a
2804 string, possibly containing wildcards `?' and `*'.
2805
2806 If FRAME is omitted or nil, use the selected frame. Each element of
2807 the result is a vector [FAMILY WIDTH POINT-SIZE WEIGHT SLANT FIXED-P
2808 FULL REGISTRY-AND-ENCODING]. FAMILY is the font family name.
2809 POINT-SIZE is the size of the font in 1/10 pt. WIDTH, WEIGHT, and
2810 SLANT are symbols describing the width, weight and slant of the font.
2811 These symbols are the same as for face attributes. FIXED-P is non-nil
2812 if the font is fixed-pitch. FULL is the full name of the font, and
2813 REGISTRY-AND-ENCODING is a string giving the registry and encoding of
2814 the font. The result list is sorted according to the current setting
2815 of the face font sort order.
2816
2817 - Function: x-font-family-list
2818
2819 Return a list of available font families on FRAME. If FRAME is
2820 omitted or nil, use the selected frame. Value is a list of conses
2821 (FAMILY . FIXED-P) where FAMILY is a font family, and FIXED-P is
2822 non-nil if fonts of that family are fixed-pitch.
2823
2824 - Variable: font-list-limit
2825
2826 Limit for font matching. If an integer > 0, font matching functions
2827 won't load more than that number of fonts when searching for a
2828 matching font. The default is currently 100.
2829
2830 +++
2831 *** Setting face attributes.
2832
2833 For the most part, the new face implementation is interface-compatible
2834 with the old one. Old face attribute related functions are now
2835 implemented in terms of the new functions `set-face-attribute' and
2836 `face-attribute'.
2837
2838 Face attributes are identified by their names which are keyword
2839 symbols. All attributes can be set to `unspecified'.
2840
2841 The following attributes are recognized:
2842
2843 `:family'
2844
2845 VALUE must be a string specifying the font family, e.g. ``courier'',
2846 or a fontset alias name. If a font family is specified, wild-cards `*'
2847 and `?' are allowed.
2848
2849 `:width'
2850
2851 VALUE specifies the relative proportionate width of the font to use.
2852 It must be one of the symbols `ultra-condensed', `extra-condensed',
2853 `condensed', `semi-condensed', `normal', `semi-expanded', `expanded',
2854 `extra-expanded', or `ultra-expanded'.
2855
2856 `:height'
2857
2858 VALUE must be either an integer specifying the height of the font to use
2859 in 1/10 pt, a floating point number specifying the amount by which to
2860 scale any underlying face, or a function, which is called with the old
2861 height (from the underlying face), and should return the new height.
2862
2863 `:weight'
2864
2865 VALUE specifies the weight of the font to use. It must be one of the
2866 symbols `ultra-bold', `extra-bold', `bold', `semi-bold', `normal',
2867 `semi-light', `light', `extra-light', `ultra-light'.
2868
2869 `:slant'
2870
2871 VALUE specifies the slant of the font to use. It must be one of the
2872 symbols `italic', `oblique', `normal', `reverse-italic', or
2873 `reverse-oblique'.
2874
2875 `:foreground', `:background'
2876
2877 VALUE must be a color name, a string.
2878
2879 `:underline'
2880
2881 VALUE specifies whether characters in FACE should be underlined. If
2882 VALUE is t, underline with foreground color of the face. If VALUE is
2883 a string, underline with that color. If VALUE is nil, explicitly
2884 don't underline.
2885
2886 `:overline'
2887
2888 VALUE specifies whether characters in FACE should be overlined. If
2889 VALUE is t, overline with foreground color of the face. If VALUE is a
2890 string, overline with that color. If VALUE is nil, explicitly don't
2891 overline.
2892
2893 `:strike-through'
2894
2895 VALUE specifies whether characters in FACE should be drawn with a line
2896 striking through them. If VALUE is t, use the foreground color of the
2897 face. If VALUE is a string, strike-through with that color. If VALUE
2898 is nil, explicitly don't strike through.
2899
2900 `:box'
2901
2902 VALUE specifies whether characters in FACE should have a box drawn
2903 around them. If VALUE is nil, explicitly don't draw boxes. If
2904 VALUE is t, draw a box with lines of width 1 in the foreground color
2905 of the face. If VALUE is a string, the string must be a color name,
2906 and the box is drawn in that color with a line width of 1. Otherwise,
2907 VALUE must be a property list of the form `(:line-width WIDTH
2908 :color COLOR :style STYLE)'. If a keyword/value pair is missing from
2909 the property list, a default value will be used for the value, as
2910 specified below. WIDTH specifies the width of the lines to draw; it
2911 defaults to 1. COLOR is the name of the color to draw in, default is
2912 the foreground color of the face for simple boxes, and the background
2913 color of the face for 3D boxes. STYLE specifies whether a 3D box
2914 should be draw. If STYLE is `released-button', draw a box looking
2915 like a released 3D button. If STYLE is `pressed-button' draw a box
2916 that appears like a pressed button. If STYLE is nil, the default if
2917 the property list doesn't contain a style specification, draw a 2D
2918 box.
2919
2920 `:inverse-video'
2921
2922 VALUE specifies whether characters in FACE should be displayed in
2923 inverse video. VALUE must be one of t or nil.
2924
2925 `:stipple'
2926
2927 If VALUE is a string, it must be the name of a file of pixmap data.
2928 The directories listed in the `x-bitmap-file-path' variable are
2929 searched. Alternatively, VALUE may be a list of the form (WIDTH
2930 HEIGHT DATA) where WIDTH and HEIGHT are the size in pixels, and DATA
2931 is a string containing the raw bits of the bitmap. VALUE nil means
2932 explicitly don't use a stipple pattern.
2933
2934 For convenience, attributes `:family', `:width', `:height', `:weight',
2935 and `:slant' may also be set in one step from an X font name:
2936
2937 `:font'
2938
2939 Set font-related face attributes from VALUE. VALUE must be a valid
2940 XLFD font name. If it is a font name pattern, the first matching font
2941 is used--this is for compatibility with the behavior of previous
2942 versions of Emacs.
2943
2944 For compatibility with Emacs 20, keywords `:bold' and `:italic' can
2945 be used to specify that a bold or italic font should be used. VALUE
2946 must be t or nil in that case. A value of `unspecified' is not allowed."
2947
2948 Please see also the documentation of `set-face-attribute' and
2949 `defface'.
2950
2951 `:inherit'
2952
2953 VALUE is the name of a face from which to inherit attributes, or a list
2954 of face names. Attributes from inherited faces are merged into the face
2955 like an underlying face would be, with higher priority than underlying faces.
2956
2957 *** Face attributes and X resources
2958
2959 The following X resource names can be used to set face attributes
2960 from X resources:
2961
2962 Face attribute X resource class
2963 -----------------------------------------------------------------------
2964 :family attributeFamily . Face.AttributeFamily
2965 :width attributeWidth Face.AttributeWidth
2966 :height attributeHeight Face.AttributeHeight
2967 :weight attributeWeight Face.AttributeWeight
2968 :slant attributeSlant Face.AttributeSlant
2969 foreground attributeForeground Face.AttributeForeground
2970 :background attributeBackground . Face.AttributeBackground
2971 :overline attributeOverline Face.AttributeOverline
2972 :strike-through attributeStrikeThrough Face.AttributeStrikeThrough
2973 :box attributeBox Face.AttributeBox
2974 :underline attributeUnderline Face.AttributeUnderline
2975 :inverse-video attributeInverse Face.AttributeInverse
2976 :stipple attributeStipple Face.AttributeStipple
2977 or attributeBackgroundPixmap
2978 Face.AttributeBackgroundPixmap
2979 :font attributeFont Face.AttributeFont
2980 :bold attributeBold Face.AttributeBold
2981 :italic attributeItalic . Face.AttributeItalic
2982 :font attributeFont Face.AttributeFont
2983
2984 +++
2985 *** Text property `face'.
2986
2987 The value of the `face' text property can now be a single face
2988 specification or a list of such specifications. Each face
2989 specification can be
2990
2991 1. A symbol or string naming a Lisp face.
2992
2993 2. A property list of the form (KEYWORD VALUE ...) where each
2994 KEYWORD is a face attribute name, and VALUE is an appropriate value
2995 for that attribute. Please see the doc string of `set-face-attribute'
2996 for face attribute names.
2997
2998 3. Conses of the form (FOREGROUND-COLOR . COLOR) or
2999 (BACKGROUND-COLOR . COLOR) where COLOR is a color name. This is
3000 for compatibility with previous Emacs versions.
3001
3002 +++
3003 ** Support functions for colors on text-only terminals.
3004
3005 The function `tty-color-define' can be used to define colors for use
3006 on TTY and MSDOS frames. It maps a color name to a color number on
3007 the terminal. Emacs defines a couple of common color mappings by
3008 default. You can get defined colors with a call to
3009 `defined-colors'. The function `tty-color-clear' can be
3010 used to clear the mapping table.
3011
3012 ** Unified support for colors independent of frame type.
3013
3014 The new functions `defined-colors', `color-defined-p', `color-values',
3015 and `display-color-p' work for any type of frame. On frames whose
3016 type is neither x nor w32, these functions transparently map X-style
3017 color specifications to the closest colors supported by the frame
3018 display. Lisp programs should use these new functions instead of the
3019 old `x-defined-colors', `x-color-defined-p', `x-color-values', and
3020 `x-display-color-p'. (The old function names are still available for
3021 compatibility; they are now aliases of the new names.) Lisp programs
3022 should no more look at the value of the variable window-system to
3023 modify their color-related behavior.
3024
3025 The primitives `color-gray-p' and `color-supported-p' also work for
3026 any frame type.
3027
3028 ** Platform-independent functions to describe display capabilities.
3029
3030 The new functions `display-mouse-p', `display-popup-menus-p',
3031 `display-graphic-p', `display-selections-p', `display-screens',
3032 `display-pixel-width', `display-pixel-height', `display-mm-width',
3033 `display-mm-height', `display-backing-store', `display-save-under',
3034 `display-planes', `display-color-cells', `display-visual-class', and
3035 `display-grayscale-p' describe the basic capabilities of a particular
3036 display. Lisp programs should call these functions instead of testing
3037 the value of the variables `window-system' or `system-type', or calling
3038 platform-specific functions such as `x-display-pixel-width'.
3039
3040 +++
3041 ** The minibuffer prompt is now actually inserted in the minibuffer.
3042
3043 This makes it possible to scroll through the prompt, if you want to.
3044
3045 The function minubuffer-prompt-end returns the current position of the
3046 end of the minibuffer prompt, if the minibuffer is current.
3047 Otherwise, it returns zero.
3048
3049 ** New `field' abstraction in buffers.
3050
3051 There is now code to support an abstraction called `fields' in emacs
3052 buffers. A field is a contiguous region of text with the same `field'
3053 property (which can be a text property or an overlay).
3054
3055 Many emacs functions, such as forward-word, forward-sentence,
3056 forward-paragraph, beginning-of-line, etc., stop moving when they come
3057 to the boundary between fields; beginning-of-line and end-of-line will
3058 not let the point move past the field boundary, but other movement
3059 commands continue into the next field if repeated. Stopping at field
3060 boundaries can be suppressed programmatically by binding
3061 `inhibit-field-text-motion' to a non-nil value around calls to these
3062 functions.
3063
3064 Now that the minibuffer prompt is inserted into the minibuffer, it is in
3065 a separate field from the user-input part of the buffer, so that common
3066 editing commands treat the user's text separately from the prompt.
3067
3068 The following functions are defined for operating on fields:
3069
3070 - Function: constrain-to-field NEW-POS OLD-POS &optional ESCAPE-FROM-EDGE ONLY-IN-LINE INHIBIT-CAPTURE-PROPERTY
3071
3072 Return the position closest to NEW-POS that is in the same field as OLD-POS.
3073
3074 A field is a region of text with the same `field' property.
3075 If NEW-POS is nil, then the current point is used instead, and set to the
3076 constrained position if that is is different.
3077
3078 If OLD-POS is at the boundary of two fields, then the allowable
3079 positions for NEW-POS depends on the value of the optional argument
3080 ESCAPE-FROM-EDGE: If ESCAPE-FROM-EDGE is nil, then NEW-POS is
3081 constrained to the field that has the same `field' char-property
3082 as any new characters inserted at OLD-POS, whereas if ESCAPE-FROM-EDGE
3083 is non-nil, NEW-POS is constrained to the union of the two adjacent
3084 fields. Additionally, if two fields are separated by another field with
3085 the special value `boundary', then any point within this special field is
3086 also considered to be `on the boundary'.
3087
3088 If the optional argument ONLY-IN-LINE is non-nil and constraining
3089 NEW-POS would move it to a different line, NEW-POS is returned
3090 unconstrained. This useful for commands that move by line, like
3091 C-n or C-a, which should generally respect field boundaries
3092 only in the case where they can still move to the right line.
3093
3094 If the optional argument INHIBIT-CAPTURE-PROPERTY is non-nil, and OLD-POS has
3095 a non-nil property of that name, then any field boundaries are ignored.
3096
3097 Field boundaries are not noticed if `inhibit-field-text-motion' is non-nil.
3098
3099 - Function: delete-field &optional POS
3100
3101 Delete the field surrounding POS.
3102 A field is a region of text with the same `field' property.
3103 If POS is nil, the value of point is used for POS.
3104
3105 - Function: field-beginning &optional POS ESCAPE-FROM-EDGE
3106
3107 Return the beginning of the field surrounding POS.
3108 A field is a region of text with the same `field' property.
3109 If POS is nil, the value of point is used for POS.
3110 If ESCAPE-FROM-EDGE is non-nil and POS is at the beginning of its
3111 field, then the beginning of the *previous* field is returned.
3112
3113 - Function: field-end &optional POS ESCAPE-FROM-EDGE
3114
3115 Return the end of the field surrounding POS.
3116 A field is a region of text with the same `field' property.
3117 If POS is nil, the value of point is used for POS.
3118 If ESCAPE-FROM-EDGE is non-nil and POS is at the end of its field,
3119 then the end of the *following* field is returned.
3120
3121 - Function: field-string &optional POS
3122
3123 Return the contents of the field surrounding POS as a string.
3124 A field is a region of text with the same `field' property.
3125 If POS is nil, the value of point is used for POS.
3126
3127 - Function: field-string-no-properties &optional POS
3128
3129 Return the contents of the field around POS, without text-properties.
3130 A field is a region of text with the same `field' property.
3131 If POS is nil, the value of point is used for POS.
3132
3133 +++
3134 ** Image support.
3135
3136 Emacs can now display images. Images are inserted into text by giving
3137 strings or buffer text a `display' text property containing one of
3138 (AREA IMAGE) or IMAGE. The display of the `display' property value
3139 replaces the display of the characters having that property.
3140
3141 If the property value has the form (AREA IMAGE), AREA must be one of
3142 `(margin left-margin)', `(margin right-margin)' or `(margin nil)'. If
3143 AREA is `(margin nil)', IMAGE will be displayed in the text area of a
3144 window, otherwise it will be displayed in the left or right marginal
3145 area.
3146
3147 IMAGE is an image specification.
3148
3149 *** Image specifications
3150
3151 Image specifications are lists of the form `(image PROPS)' where PROPS
3152 is a property list whose keys are keyword symbols. Each
3153 specifications must contain a property `:type TYPE' with TYPE being a
3154 symbol specifying the image type, e.g. `xbm'. Properties not
3155 described below are ignored.
3156
3157 The following is a list of properties all image types share.
3158
3159 `:ascent ASCENT'
3160
3161 ASCENT must be a number in the range 0..100, or the symbol `center'.
3162 If it is a number, it specifies the percentage of the image's height
3163 to use for its ascent.
3164
3165 If not specified, ASCENT defaults to the value 50 which means that the
3166 image will be centered with the base line of the row it appears in.
3167
3168 If ASCENT is `center' the image is vertically centered around a
3169 centerline which is the vertical center of text drawn at the position
3170 of the image, in the manner specified by the text properties and
3171 overlays that apply to the image.
3172
3173 `:margin MARGIN'
3174
3175 MARGIN must be a number >= 0 specifying how many pixels to put as
3176 margin around the image. Default is 0.
3177
3178 `:relief RELIEF'
3179
3180 RELIEF is analogous to the `:relief' attribute of faces. Puts a relief
3181 around an image.
3182
3183 `:algorithm ALGO'
3184
3185 Apply an image algorithm to the image before displaying it.
3186
3187 ALGO `laplace' or `emboss' means apply a Laplace or ``emboss''
3188 edge-detection algorithm to the image.
3189
3190 ALGO `(edge-detection :matrix MATRIX :color-adjust ADJUST)' means
3191 apply a general edge-detection algorithm. MATRIX must be either a
3192 nine-element list or a nine-element vector of numbers. A pixel at
3193 position x/y in the transformed image is computed from original pixels
3194 around that position. MATRIX specifies, for each pixel in the
3195 neighborhood of x/y, a factor with which that pixel will influence the
3196 transformed pixel; element 0 specifies the factor for the pixel at
3197 x-1/y-1, element 1 the factor for the pixel at x/y-1 etc. as shown
3198 below.
3199
3200 (x-1/y-1 x/y-1 x+1/y-1
3201 x-1/y x/y x+1/y
3202 x-1/y+1 x/y+1 x+1/y+1)
3203
3204 The resulting pixel is computed from the color intensity of the color
3205 resulting from summing up the RGB values of surrounding pixels,
3206 multiplied by the specified factors, and dividing that sum by the sum
3207 of the factors' absolute values.
3208
3209 Laplace edge-detection currently uses a matrix of
3210
3211 (1 0 0
3212 0 0 0
3213 9 9 -1)
3214
3215 Emboss edge-detection uses a matrix of
3216
3217 ( 2 -1 0
3218 -1 0 1
3219 0 1 -2)
3220
3221 ALGO `disabled' means transform the image so that it looks
3222 ``disabled''.
3223
3224 `:mask MASK'
3225
3226 If MASK is `heuristic' or `(heuristic BG)', build a clipping mask for
3227 the image, so that the background of a frame is visible behind the
3228 image. If BG is not specified, or if BG is t, determine the
3229 background color of the image by looking at the 4 corners of the
3230 image, assuming the most frequently occuring color from the corners is
3231 the background color of the image. Otherwise, BG must be a list `(RED
3232 GREEN BLUE)' specifying the color to assume for the background of the
3233 image.
3234
3235 If MASK is nil, remove a mask from the image, if it has one. Images
3236 in some formats include a mask which can be removed by specifying
3237 `:mask nil'.
3238
3239 `:file FILE'
3240
3241 Load image from FILE. If FILE is not absolute after expanding it,
3242 search for the image in `data-directory'. Some image types support
3243 building images from data. When this is done, no `:file' property
3244 may be present in the image specification.
3245
3246 `:data DATA'
3247
3248 Get image data from DATA. (As of this writing, this is not yet
3249 supported for image type `postscript'). Either :file or :data may be
3250 present in an image specification, but not both. All image types
3251 support strings as DATA, some types allow additional types of DATA.
3252
3253 *** Supported image types
3254
3255 **** XBM, image type `xbm'.
3256
3257 XBM images don't require an external library. Additional image
3258 properties supported are
3259
3260 `:foreground FG'
3261
3262 FG must be a string specifying the image foreground color. Default
3263 is the frame's foreground.
3264
3265 `:background FG'
3266
3267 BG must be a string specifying the image foreground color. Default is
3268 the frame's background color.
3269
3270 XBM images can be constructed from data instead of file. In this
3271 case, the image specification must contain the following properties
3272 instead of a `:file' property.
3273
3274 `:width WIDTH'
3275
3276 WIDTH specifies the width of the image in pixels.
3277
3278 `:height HEIGHT'
3279
3280 HEIGHT specifies the height of the image in pixels.
3281
3282 `:data DATA'
3283
3284 DATA must be either
3285
3286 1. a string large enough to hold the bitmap data, i.e. it must
3287 have a size >= (WIDTH + 7) / 8 * HEIGHT
3288
3289 2. a bool-vector of size >= WIDTH * HEIGHT
3290
3291 3. a vector of strings or bool-vectors, one for each line of the
3292 bitmap.
3293
3294 4. a string that's an in-memory XBM file. Neither width nor
3295 height may be specified in this case because these are defined
3296 in the file.
3297
3298 **** XPM, image type `xpm'
3299
3300 XPM images require the external library `libXpm', package
3301 `xpm-3.4k.tar.gz', version 3.4k or later. Make sure the library is
3302 found when Emacs is configured by supplying appropriate paths via
3303 `--x-includes' and `--x-libraries'.
3304
3305 Additional image properties supported are:
3306
3307 `:color-symbols SYMBOLS'
3308
3309 SYMBOLS must be a list of pairs (NAME . COLOR), with NAME being the
3310 name of color as it appears in an XPM file, and COLOR being an X color
3311 name.
3312
3313 XPM images can be built from memory instead of files. In that case,
3314 add a `:data' property instead of a `:file' property.
3315
3316 The XPM library uses libz in its implementation so that it is able
3317 to display compressed images.
3318
3319 **** PBM, image type `pbm'
3320
3321 PBM images don't require an external library. Color, gray-scale and
3322 mono images are supported. There are no additional image properties
3323 defined.
3324
3325 **** JPEG, image type `jpeg'
3326
3327 Support for JPEG images requires the external library `libjpeg',
3328 package `jpegsrc.v6a.tar.gz', or later. Additional image properties
3329 are:
3330
3331 **** TIFF, image type `tiff'
3332
3333 Support for TIFF images requires the external library `libtiff',
3334 package `tiff-v3.4-tar.gz', or later. There are no additional image
3335 properties defined.
3336
3337 **** GIF, image type `gif'
3338
3339 Support for GIF images requires the external library `libungif', package
3340 `libungif-4.1.0', or later.
3341
3342 Additional image properties supported are:
3343
3344 `:index INDEX'
3345
3346 INDEX must be an integer >= 0. Load image number INDEX from a
3347 multi-image GIF file. An error is signalled if INDEX is too large.
3348
3349 This could be used to implement limited support for animated GIFs.
3350 For example, the following function displays a multi-image GIF file
3351 at point-min in the current buffer, switching between sub-images
3352 every 0.1 seconds.
3353
3354 (defun show-anim (file max)
3355 "Display multi-image GIF file FILE which contains MAX subimages."
3356 (display-anim (current-buffer) file 0 max t))
3357
3358 (defun display-anim (buffer file idx max first-time)
3359 (when (= idx max)
3360 (setq idx 0))
3361 (let ((img (create-image file nil nil :index idx)))
3362 (save-excursion
3363 (set-buffer buffer)
3364 (goto-char (point-min))
3365 (unless first-time (delete-char 1))
3366 (insert-image img "x"))
3367 (run-with-timer 0.1 nil 'display-anim buffer file (1+ idx) max nil)))
3368
3369 **** PNG, image type `png'
3370
3371 Support for PNG images requires the external library `libpng',
3372 package `libpng-1.0.2.tar.gz', or later. There are no additional image
3373 properties defined.
3374
3375 **** Ghostscript, image type `postscript'.
3376
3377 Additional image properties supported are:
3378
3379 `:pt-width WIDTH'
3380
3381 WIDTH is width of the image in pt (1/72 inch). WIDTH must be an
3382 integer. This is a required property.
3383
3384 `:pt-height HEIGHT'
3385
3386 HEIGHT specifies the height of the image in pt (1/72 inch). HEIGHT
3387 must be a integer. This is an required property.
3388
3389 `:bounding-box BOX'
3390
3391 BOX must be a list or vector of 4 integers giving the bounding box of
3392 the PS image, analogous to the `BoundingBox' comment found in PS
3393 files. This is an required property.
3394
3395 Part of the Ghostscript interface is implemented in Lisp. See
3396 lisp/gs.el.
3397
3398 *** Lisp interface.
3399
3400 The variable `image-types' contains a list of those image types
3401 which are supported in the current configuration.
3402
3403 Images are stored in an image cache and removed from the cache when
3404 they haven't been displayed for `image-cache-eviction-delay seconds.
3405 The function `clear-image-cache' can be used to clear the image cache
3406 manually. Images in the cache are compared with `equal', i.e. all
3407 images with `equal' specifications share the same image.
3408
3409 *** Simplified image API, image.el
3410
3411 The new Lisp package image.el contains functions that simplify image
3412 creation and putting images into text. The function `create-image'
3413 can be used to create images. The macro `defimage' can be used to
3414 define an image based on available image types. The functions
3415 `put-image' and `insert-image' can be used to insert an image into a
3416 buffer.
3417
3418 +++
3419 ** Display margins.
3420
3421 Windows can now have margins which are used for special text
3422 and images.
3423
3424 To give a window margins, either set the buffer-local variables
3425 `left-margin-width' and `right-margin-width', or call
3426 `set-window-margins'. The function `window-margins' can be used to
3427 obtain the current settings. To make `left-margin-width' and
3428 `right-margin-width' take effect, you must set them before displaying
3429 the buffer in a window, or use `set-window-buffer' to force an update
3430 of the display margins.
3431
3432 You can put text in margins by giving it a `display' text property
3433 containing a pair of the form `(LOCATION . VALUE)', where LOCATION is
3434 one of `left-margin' or `right-margin' or nil. VALUE can be either a
3435 string, an image specification or a stretch specification (see later
3436 in this file).
3437
3438 +++
3439 ** Help display
3440
3441 Emacs displays short help messages in the echo area, when the mouse
3442 moves over a tool-bar item or a piece of text that has a text property
3443 `help-echo'. This feature also applies to strings in the mode line
3444 that have a `help-echo' property.
3445
3446 If the value of the `help-echo' property is a function, that function
3447 is called with three arguments WINDOW, OBJECT and POSITION. WINDOW is
3448 the window in which the help was found.
3449
3450 If OBJECT is a buffer, POS is the position in the buffer where the
3451 `help-echo' text property was found.
3452
3453 If OBJECT is an overlay, that overlay has a `help-echo' property, and
3454 POS is the position in the overlay's buffer under the mouse.
3455
3456 If OBJECT is a string (an overlay string or a string displayed with
3457 the `display' property), POS is the position in that string under the
3458 mouse.
3459
3460 If the value of the `help-echo' property is neither a function nor a
3461 string, it is evaluated to obtain a help string.
3462
3463 For tool-bar and menu-bar items, their key definition is used to
3464 determine the help to display. If their definition contains a
3465 property `:help FORM', FORM is evaluated to determine the help string.
3466 For tool-bar items without a help form, the caption of the item is
3467 used as help string.
3468
3469 The hook `show-help-function' can be set to a function that displays
3470 the help string differently. For example, enabling a tooltip window
3471 causes the help display to appear there instead of in the echo area.
3472
3473 +++
3474 ** Vertical fractional scrolling.
3475
3476 The display of text in windows can be scrolled smoothly in pixels.
3477 This is useful, for example, for making parts of large images visible.
3478
3479 The function `window-vscroll' returns the current value of vertical
3480 scrolling, a non-negative fraction of the canonical character height.
3481 The function `set-window-vscroll' can be used to set the vertical
3482 scrolling value. Here is an example of how these function might be
3483 used.
3484
3485 (global-set-key [A-down]
3486 #'(lambda ()
3487 (interactive)
3488 (set-window-vscroll (selected-window)
3489 (+ 0.5 (window-vscroll)))))
3490 (global-set-key [A-up]
3491 #'(lambda ()
3492 (interactive)
3493 (set-window-vscroll (selected-window)
3494 (- (window-vscroll) 0.5)))))
3495
3496 +++
3497 ** New hook `fontification-functions'.
3498
3499 Functions from `fontification-functions' are called from redisplay
3500 when it encounters a region of text that is not yet fontified. This
3501 variable automatically becomes buffer-local when set. Each function
3502 is called with one argument, POS.
3503
3504 At least one of the hook functions should fontify one or more
3505 characters starting at POS in the current buffer. It should mark them
3506 as fontified by giving them a non-nil value of the `fontified' text
3507 property. It may be reasonable for these functions to check for the
3508 `fontified' property and not put it back on, but they do not have to.
3509
3510 +++
3511 ** Tool bar support.
3512
3513 Emacs supports a tool bar at the top of a frame under X. The frame
3514 parameter `tool-bar-lines' (X resource "toolBar", class "ToolBar")
3515 controls how may lines to reserve for the tool bar. A zero value
3516 suppresses the tool bar. If the value is non-zero and
3517 `auto-resize-tool-bars' is non-nil the tool bar's size will be changed
3518 automatically so that all tool bar items are visible.
3519
3520 *** Tool bar item definitions
3521
3522 Tool bar items are defined using `define-key' with a prefix-key
3523 `tool-bar'. For example `(define-key global-map [tool-bar item1] ITEM)'
3524 where ITEM is a list `(menu-item CAPTION BINDING PROPS...)'.
3525
3526 CAPTION is the caption of the item, If it's not a string, it is
3527 evaluated to get a string. The caption is currently not displayed in
3528 the tool bar, but it is displayed if the item doesn't have a `:help'
3529 property (see below).
3530
3531 BINDING is the tool bar item's binding. Tool bar items with keymaps as
3532 binding are currently ignored.
3533
3534 The following properties are recognized:
3535
3536 `:enable FORM'.
3537
3538 FORM is evaluated and specifies whether the tool bar item is enabled
3539 or disabled.
3540
3541 `:visible FORM'
3542
3543 FORM is evaluated and specifies whether the tool bar item is displayed.
3544
3545 `:filter FUNCTION'
3546
3547 FUNCTION is called with one parameter, the same list BINDING in which
3548 FUNCTION is specified as the filter. The value FUNCTION returns is
3549 used instead of BINDING to display this item.
3550
3551 `:button (TYPE SELECTED)'
3552
3553 TYPE must be one of `:radio' or `:toggle'. SELECTED is evaluated
3554 and specifies whether the button is selected (pressed) or not.
3555
3556 `:image IMAGES'
3557
3558 IMAGES is either a single image specification or a vector of four
3559 image specifications. If it is a vector, this table lists the
3560 meaning of each of the four elements:
3561
3562 Index Use when item is
3563 ----------------------------------------
3564 0 enabled and selected
3565 1 enabled and deselected
3566 2 disabled and selected
3567 3 disabled and deselected
3568
3569 If IMAGE is a single image specification, a Laplace edge-detection
3570 algorithm is used on that image to draw the image in disabled state.
3571
3572 `:help HELP-STRING'.
3573
3574 Gives a help string to display for the tool bar item. This help
3575 is displayed when the mouse is moved over the item.
3576
3577 The function `toolbar-add-item' is a convenience function for adding
3578 toolbar items generally, and `tool-bar-add-item-from-menu' can be used
3579 to define a toolbar item with a binding copied from an item on the
3580 menu bar.
3581
3582 *** Tool-bar-related variables.
3583
3584 If `auto-resize-tool-bar' is non-nil, the tool bar will automatically
3585 resize to show all defined tool bar items. It will never grow larger
3586 than 1/4 of the frame's size.
3587
3588 If `auto-raise-tool-bar-buttons' is non-nil, tool bar buttons will be
3589 raised when the mouse moves over them.
3590
3591 You can add extra space between tool bar items by setting
3592 `tool-bar-button-margin' to a positive integer specifying a number of
3593 pixels. Default is 1.
3594
3595 You can change the shadow thickness of tool bar buttons by setting
3596 `tool-bar-button-relief' to an integer. Default is 3.
3597
3598 *** Tool-bar clicks with modifiers.
3599
3600 You can bind commands to clicks with control, shift, meta etc. on
3601 a tool bar item. If
3602
3603 (define-key global-map [tool-bar shell]
3604 '(menu-item "Shell" shell
3605 :image (image :type xpm :file "shell.xpm")))
3606
3607 is the original tool bar item definition, then
3608
3609 (define-key global-map [tool-bar S-shell] 'some-command)
3610
3611 makes a binding to run `some-command' for a shifted click on the same
3612 item.
3613
3614 ** Mode line changes.
3615
3616 +++
3617 *** Mouse-sensitive mode line.
3618
3619 The mode line can be made mouse-sensitive by displaying strings there
3620 that have a `local-map' text property. There are three ways to display
3621 a string with a `local-map' property in the mode line.
3622
3623 1. The mode line spec contains a variable whose string value has
3624 a `local-map' text property.
3625
3626 2. The mode line spec contains a format specifier (e.g. `%12b'), and
3627 that format specifier has a `local-map' property.
3628
3629 3. The mode line spec contains a list containing `:eval FORM'. FORM
3630 is evaluated. If the result is a string, and that string has a
3631 `local-map' property.
3632
3633 The same mechanism is used to determine the `face' and `help-echo'
3634 properties of strings in the mode line. See `bindings.el' for an
3635 example.
3636
3637 *** If a mode line element has the form `(:eval FORM)', FORM is
3638 evaluated and the result is used as mode line element.
3639
3640 +++
3641 *** You can suppress mode-line display by setting the buffer-local
3642 variable mode-line-format to nil.
3643
3644 +++
3645 *** A headerline can now be displayed at the top of a window.
3646
3647 This mode line's contents are controlled by the new variable
3648 `header-line-format' and `default-header-line-format' which are
3649 completely analogous to `mode-line-format' and
3650 `default-mode-line-format'. A value of nil means don't display a top
3651 line.
3652
3653 The appearance of top mode lines is controlled by the face
3654 `header-line'.
3655
3656 The function `coordinates-in-window-p' returns `header-line' for a
3657 position in the header-line.
3658
3659 +++
3660 ** Text property `display'
3661
3662 The `display' text property is used to insert images into text,
3663 replace text with other text, display text in marginal area, and it is
3664 also used to control other aspects of how text displays. The value of
3665 the `display' property should be a display specification, as described
3666 below, or a list or vector containing display specifications.
3667
3668 *** Replacing text, displaying text in marginal areas
3669
3670 To replace the text having the `display' property with some other
3671 text, use a display specification of the form `(LOCATION STRING)'.
3672
3673 If LOCATION is `(margin left-margin)', STRING is displayed in the left
3674 marginal area, if it is `(margin right-margin)', it is displayed in
3675 the right marginal area, and if LOCATION is `(margin nil)' STRING
3676 is displayed in the text. In the latter case you can also use the
3677 simpler form STRING as property value.
3678
3679 *** Variable width and height spaces
3680
3681 To display a space of fractional width or height, use a display
3682 specification of the form `(LOCATION STRECH)'. If LOCATION is
3683 `(margin left-margin)', the space is displayed in the left marginal
3684 area, if it is `(margin right-margin)', it is displayed in the right
3685 marginal area, and if LOCATION is `(margin nil)' the space is
3686 displayed in the text. In the latter case you can also use the
3687 simpler form STRETCH as property value.
3688
3689 The stretch specification STRETCH itself is a list of the form `(space
3690 PROPS)', where PROPS is a property list which can contain the
3691 properties described below.
3692
3693 The display of the fractional space replaces the display of the
3694 characters having the `display' property.
3695
3696 - :width WIDTH
3697
3698 Specifies that the space width should be WIDTH times the normal
3699 character width. WIDTH can be an integer or floating point number.
3700
3701 - :relative-width FACTOR
3702
3703 Specifies that the width of the stretch should be computed from the
3704 first character in a group of consecutive characters that have the
3705 same `display' property. The computation is done by multiplying the
3706 width of that character by FACTOR.
3707
3708 - :align-to HPOS
3709
3710 Specifies that the space should be wide enough to reach HPOS. The
3711 value HPOS is measured in units of the normal character width.
3712
3713 Exactly one of the above properties should be used.
3714
3715 - :height HEIGHT
3716
3717 Specifies the height of the space, as HEIGHT, measured in terms of the
3718 normal line height.
3719
3720 - :relative-height FACTOR
3721
3722 The height of the space is computed as the product of the height
3723 of the text having the `display' property and FACTOR.
3724
3725 - :ascent ASCENT
3726
3727 Specifies that ASCENT percent of the height of the stretch should be
3728 used for the ascent of the stretch, i.e. for the part above the
3729 baseline. The value of ASCENT must be a non-negative number less or
3730 equal to 100.
3731
3732 You should not use both `:height' and `:relative-height' together.
3733
3734 *** Images
3735
3736 A display specification for an image has the form `(LOCATION
3737 . IMAGE)', where IMAGE is an image specification. The image replaces,
3738 in the display, the characters having this display specification in
3739 their `display' text property. If LOCATION is `(margin left-margin)',
3740 the image will be displayed in the left marginal area, if it is
3741 `(margin right-margin)' it will be displayed in the right marginal
3742 area, and if LOCATION is `(margin nil)' the image will be displayed in
3743 the text. In the latter case you can also use the simpler form IMAGE
3744 as display specification.
3745
3746 *** Other display properties
3747
3748 - :space-width FACTOR
3749
3750 Specifies that space characters in the text having that property
3751 should be displayed FACTOR times as wide as normal; FACTOR must be an
3752 integer or float.
3753
3754 - :height HEIGHT
3755
3756 Display text having this property in a font that is smaller or larger.
3757
3758 If HEIGHT is a list of the form `(+ N)', where N is an integer, that
3759 means to use a font that is N steps larger. If HEIGHT is a list of
3760 the form `(- N)', that means to use a font that is N steps smaller. A
3761 ``step'' is defined by the set of available fonts; each size for which
3762 a font is available counts as a step.
3763
3764 If HEIGHT is a number, that means to use a font that is HEIGHT times
3765 as tall as the frame's default font.
3766
3767 If HEIGHT is a symbol, it is called as a function with the current
3768 height as argument. The function should return the new height to use.
3769
3770 Otherwise, HEIGHT is evaluated to get the new height, with the symbol
3771 `height' bound to the current specified font height.
3772
3773 - :raise FACTOR
3774
3775 FACTOR must be a number, specifying a multiple of the current
3776 font's height. If it is positive, that means to display the characters
3777 raised. If it is negative, that means to display them lower down. The
3778 amount of raising or lowering is computed without taking account of the
3779 `:height' subproperty.
3780
3781 *** Conditional display properties
3782
3783 All display specifications can be conditionalized. If a specification
3784 has the form `(:when CONDITION . SPEC)', the specification SPEC
3785 applies only when CONDITION yields a non-nil value when evaluated.
3786 During evaluattion, point is temporarily set to the end position of
3787 the text having the `display' property.
3788
3789 The normal specification consisting of SPEC only is equivalent to
3790 `(:when t SPEC)'.
3791
3792 +++
3793 ** New menu separator types.
3794
3795 Emacs now supports more than one menu separator type. Menu items with
3796 item names consisting of dashes only (including zero dashes) are
3797 treated like before. In addition, the following item names are used
3798 to specify other menu separator types.
3799
3800 - `--no-line' or `--space', or `--:space', or `--:noLine'
3801
3802 No separator lines are drawn, but a small space is inserted where the
3803 separator occurs.
3804
3805 - `--single-line' or `--:singleLine'
3806
3807 A single line in the menu's foreground color.
3808
3809 - `--double-line' or `--:doubleLine'
3810
3811 A double line in the menu's foreground color.
3812
3813 - `--single-dashed-line' or `--:singleDashedLine'
3814
3815 A single dashed line in the menu's foreground color.
3816
3817 - `--double-dashed-line' or `--:doubleDashedLine'
3818
3819 A double dashed line in the menu's foreground color.
3820
3821 - `--shadow-etched-in' or `--:shadowEtchedIn'
3822
3823 A single line with 3D sunken appearance. This is the the form
3824 displayed for item names consisting of dashes only.
3825
3826 - `--shadow-etched-out' or `--:shadowEtchedOut'
3827
3828 A single line with 3D raised appearance.
3829
3830 - `--shadow-etched-in-dash' or `--:shadowEtchedInDash'
3831
3832 A single dashed line with 3D sunken appearance.
3833
3834 - `--shadow-etched-out-dash' or `--:shadowEtchedOutDash'
3835
3836 A single dashed line with 3D raise appearance.
3837
3838 - `--shadow-double-etched-in' or `--:shadowDoubleEtchedIn'
3839
3840 Two lines with 3D sunken appearance.
3841
3842 - `--shadow-double-etched-out' or `--:shadowDoubleEtchedOut'
3843
3844 Two lines with 3D raised appearance.
3845
3846 - `--shadow-double-etched-in-dash' or `--:shadowDoubleEtchedInDash'
3847
3848 Two dashed lines with 3D sunken appearance.
3849
3850 - `--shadow-double-etched-out-dash' or `--:shadowDoubleEtchedOutDash'
3851
3852 Two dashed lines with 3D raised appearance.
3853
3854 Under LessTif/Motif, the last four separator types are displayed like
3855 the corresponding single-line separators.
3856
3857 +++
3858 ** New frame parameters for scroll bar colors.
3859
3860 The new frame parameters `scroll-bar-foreground' and
3861 `scroll-bar-background' can be used to change scroll bar colors.
3862 Their value must be either a color name, a string, or nil to specify
3863 that scroll bars should use a default color. For toolkit scroll bars,
3864 default colors are toolkit specific. For non-toolkit scroll bars, the
3865 default background is the background color of the frame, and the
3866 default foreground is black.
3867
3868 The X resource name of these parameters are `scrollBarForeground'
3869 (class ScrollBarForeground) and `scrollBarBackground' (class
3870 `ScrollBarBackground').
3871
3872 Setting these parameters overrides toolkit specific X resource
3873 settings for scroll bar colors.
3874
3875 +++
3876 ** You can set `redisplay-dont-pause' to a non-nil value to prevent
3877 display updates from being interrupted when input is pending.
3878
3879 ---
3880 ** Changing a window's width may now change its window start if it
3881 starts on a continuation line. The new window start is computed based
3882 on the window's new width, starting from the start of the continued
3883 line as the start of the screen line with the minimum distance from
3884 the original window start.
3885
3886 ---
3887 ** The variable `hscroll-step' and the functions
3888 `hscroll-point-visible' and `hscroll-window-column' have been removed
3889 now that proper horizontal scrolling is implemented.
3890
3891 +++
3892 ** Windows can now be made fixed-width and/or fixed-height.
3893
3894 A window is fixed-size if its buffer has a buffer-local variable
3895 `window-size-fixed' whose value is not nil. A value of `height' makes
3896 windows fixed-height, a value of `width' makes them fixed-width, any
3897 other non-nil value makes them both fixed-width and fixed-height.
3898
3899 The following code makes all windows displaying the current buffer
3900 fixed-width and fixed-height.
3901
3902 (set (make-local-variable 'window-size-fixed) t)
3903
3904 A call to enlarge-window on a window gives an error if that window is
3905 fixed-width and it is tried to change the window's width, or if the
3906 window is fixed-height, and it is tried to change its height. To
3907 change the size of a fixed-size window, bind `window-size-fixed'
3908 temporarily to nil, for example
3909
3910 (let ((window-size-fixed nil))
3911 (enlarge-window 10))
3912
3913 Likewise, an attempt to split a fixed-height window vertically,
3914 or a fixed-width window horizontally results in a error.
3915
3916 ** The cursor-type frame parameter is now supported on MS-DOS
3917 terminals. When Emacs starts, it by default changes the cursor shape
3918 to a solid box, as it does on Unix. The `cursor-type' frame parameter
3919 overrides this as it does on Unix, except that the bar cursor is
3920 horizontal rather than vertical (since the MS-DOS display doesn't
3921 support a vertical-bar cursor).
3922
3923
3924 ^L
3925 * Emacs 20.7 is a bug-fix release with few user-visible changes
3926
3927 ** It is now possible to use CCL-based coding systems for keyboard
3928 input.
3929
3930 ** ange-ftp now handles FTP security extensions, like Kerberos.
3931
3932 ** Rmail has been extended to recognize more forms of digest messages.
3933
3934 ** Now, most coding systems set in keyboard coding system work not
3935 only for character input, but also in incremental search. The
3936 exceptions are such coding systems that handle 2-byte character sets
3937 (e.g euc-kr, euc-jp) and that use ISO's escape sequence
3938 (e.g. iso-2022-jp). They are ignored in incremental search.
3939
3940 ** Support for Macintosh PowerPC-based machines running GNU/Linux has
3941 been added.
3942
3943 ^L
3944 * Emacs 20.6 is a bug-fix release with one user-visible change
3945
3946 ** Support for ARM-based non-RISCiX machines has been added.
3947
3948 ^L
3949 * Emacs 20.5 is a bug-fix release with no user-visible changes.
3950
3951 ** Not new, but not mentioned before:
3952 M-w when Transient Mark mode is enabled disables the mark.
3953 \f
3954 * Changes in Emacs 20.4
3955
3956 ** Init file may be called .emacs.el.
3957
3958 You can now call the Emacs init file `.emacs.el'.
3959 Formerly the name had to be `.emacs'. If you use the name
3960 `.emacs.el', you can byte-compile the file in the usual way.
3961
3962 If both `.emacs' and `.emacs.el' exist, the latter file
3963 is the one that is used.
3964
3965 ** shell-command, and shell-command-on-region, now return
3966 the exit code of the command (unless it is asynchronous).
3967 Also, you can specify a place to put the error output,
3968 separate from the command's regular output.
3969 Interactively, the variable shell-command-default-error-buffer
3970 says where to put error output; set it to a buffer name.
3971 In calls from Lisp, an optional argument ERROR-BUFFER specifies
3972 the buffer name.
3973
3974 When you specify a non-nil error buffer (or buffer name), any error
3975 output is inserted before point in that buffer, with \f\n to separate
3976 it from the previous batch of error output. The error buffer is not
3977 cleared, so error output from successive commands accumulates there.
3978
3979 ** Setting the default value of enable-multibyte-characters to nil in
3980 the .emacs file, either explicitly using setq-default, or via Custom,
3981 is now essentially equivalent to using --unibyte: all buffers
3982 created during startup will be made unibyte after loading .emacs.
3983
3984 ** C-x C-f now handles the wildcards * and ? in file names. For
3985 example, typing C-x C-f c*.c RET visits all the files whose names
3986 match c*.c. To visit a file whose name contains * or ?, add the
3987 quoting sequence /: to the beginning of the file name.
3988
3989 ** The M-x commands keep-lines, flush-lines and count-matches
3990 now have the same feature as occur and query-replace:
3991 if the pattern contains any upper case letters, then
3992 they never ignore case.
3993
3994 ** The end-of-line format conversion feature previously mentioned
3995 under `* Emacs 20.1 changes for MS-DOS and MS-Windows' actually
3996 applies to all operating systems. Emacs recognizes from the contents
3997 of a file what convention it uses to separate lines--newline, CRLF, or
3998 just CR--and automatically converts the contents to the normal Emacs
3999 convention (using newline to separate lines) for editing. This is a
4000 part of the general feature of coding system conversion.
4001
4002 If you subsequently save the buffer, Emacs converts the text back to
4003 the same format that was used in the file before.
4004
4005 You can turn off end-of-line conversion by setting the variable
4006 `inhibit-eol-conversion' to non-nil, e.g. with Custom in the MULE group.
4007
4008 ** The character set property `prefered-coding-system' has been
4009 renamed to `preferred-coding-system', for the sake of correct spelling.
4010 This is a fairly internal feature, so few programs should be affected.
4011
4012 ** Mode-line display of end-of-line format is changed.
4013 The indication of the end-of-line format of the file visited by a
4014 buffer is now more explicit when that format is not the usual one for
4015 your operating system. For example, the DOS-style end-of-line format
4016 is displayed as "(DOS)" on Unix and GNU/Linux systems. The usual
4017 end-of-line format is still displayed as a single character (colon for
4018 Unix, backslash for DOS and Windows, and forward slash for the Mac).
4019
4020 The values of the variables eol-mnemonic-unix, eol-mnemonic-dos,
4021 eol-mnemonic-mac, and eol-mnemonic-undecided, which are strings,
4022 control what is displayed in the mode line for each end-of-line
4023 format. You can now customize these variables.
4024
4025 ** In the previous version of Emacs, tar-mode didn't work well if a
4026 filename contained non-ASCII characters. Now this is fixed. Such a
4027 filename is decoded by file-name-coding-system if the default value of
4028 enable-multibyte-characters is non-nil.
4029
4030 ** The command temp-buffer-resize-mode toggles a minor mode
4031 in which temporary buffers (such as help buffers) are given
4032 windows just big enough to hold the whole contents.
4033
4034 ** If you use completion.el, you must now run the function
4035 dynamic-completion-mode to enable it. Just loading the file
4036 doesn't have any effect.
4037
4038 ** In Flyspell mode, the default is now to make just one Ispell process,
4039 not one per buffer.
4040
4041 ** If you use iswitchb but do not call (iswitchb-default-keybindings) to
4042 use the default keybindings, you will need to add the following line:
4043 (add-hook 'minibuffer-setup-hook 'iswitchb-minibuffer-setup)
4044
4045 ** Auto-show mode is no longer enabled just by loading auto-show.el.
4046 To control it, set `auto-show-mode' via Custom or use the
4047 `auto-show-mode' command.
4048
4049 ** Handling of X fonts' ascent/descent parameters has been changed to
4050 avoid redisplay problems. As a consequence, compared with previous
4051 versions the line spacing and frame size now differ with some font
4052 choices, typically increasing by a pixel per line. This change
4053 occurred in version 20.3 but was not documented then.
4054
4055 ** If you select the bar cursor style, it uses the frame's
4056 cursor-color, rather than the cursor foreground pixel.
4057
4058 ** In multibyte mode, Rmail decodes incoming MIME messages using the
4059 character set specified in the message. If you want to disable this
4060 feature, set the variable rmail-decode-mime-charset to nil.
4061
4062 ** Not new, but not mentioned previously in NEWS: when you use #! at
4063 the beginning of a file to make it executable and specify an
4064 interpreter program, Emacs looks on the second line for the -*- mode
4065 and variable specification, as well as on the first line.
4066
4067 ** Support for IBM codepage encoding of non-ASCII characters.
4068
4069 The new command M-x codepage-setup creates a special coding system
4070 that can be used to convert text between a specific IBM codepage and
4071 one of the character sets built into Emacs which matches that
4072 codepage. For example, codepage 850 corresponds to Latin-1 character
4073 set, codepage 855 corresponds to Cyrillic-ISO character set, etc.
4074
4075 Windows codepages 1250, 1251 and some others, where Windows deviates
4076 from the corresponding ISO character set, are also supported.
4077
4078 IBM box-drawing characters and other glyphs which don't have
4079 equivalents in the corresponding ISO character set, are converted to
4080 a character defined by dos-unsupported-char-glyph on MS-DOS, and to
4081 `?' on other systems.
4082
4083 IBM codepages are widely used on MS-DOS and MS-Windows, so this
4084 feature is most useful on those platforms, but it can also be used on
4085 Unix.
4086
4087 Emacs compiled for MS-DOS automatically loads the support for the
4088 current codepage when it starts.
4089
4090 ** Mail changes
4091
4092 *** When mail is sent using compose-mail (C-x m), and if
4093 `mail-send-nonascii' is set to the new default value `mime',
4094 appropriate MIME headers are added. The headers are added only if
4095 non-ASCII characters are present in the body of the mail, and no other
4096 MIME headers are already present. For example, the following three
4097 headers are added if the coding system used in the *mail* buffer is
4098 latin-1:
4099
4100 MIME-version: 1.0
4101 Content-type: text/plain; charset=iso-8859-1
4102 Content-Transfer-Encoding: 8bit
4103
4104 *** The new variable default-sendmail-coding-system specifies the
4105 default way to encode outgoing mail. This has higher priority than
4106 default-buffer-file-coding-system but has lower priority than
4107 sendmail-coding-system and the local value of
4108 buffer-file-coding-system.
4109
4110 You should not set this variable manually. Instead, set
4111 sendmail-coding-system to specify a fixed encoding for all outgoing
4112 mail.
4113
4114 *** When you try to send a message that contains non-ASCII characters,
4115 if the coding system specified by those variables doesn't handle them,
4116 Emacs will ask you to select a suitable coding system while showing a
4117 list of possible coding systems.
4118
4119 ** CC Mode changes
4120
4121 *** c-default-style can now take an association list that maps major
4122 modes to style names. When this variable is an alist, Java mode no
4123 longer hardcodes a setting to "java" style. See the variable's
4124 docstring for details.
4125
4126 *** It's now possible to put a list as the offset on a syntactic
4127 symbol. The list is evaluated recursively until a non-nil offset is
4128 found. This is useful to combine several lineup functions to act in a
4129 prioritized order on a single line. However, none of the supplied
4130 lineup functions use this feature currently.
4131
4132 *** New syntactic symbol catch-clause, which is used on the "catch" and
4133 "finally" lines in try-catch constructs in C++ and Java.
4134
4135 *** New cleanup brace-catch-brace on c-cleanup-list, which does for
4136 "catch" lines what brace-elseif-brace does for "else if" lines.
4137
4138 *** The braces of Java anonymous inner classes are treated separately
4139 from the braces of other classes in auto-newline mode. Two new
4140 symbols inexpr-class-open and inexpr-class-close may be used on
4141 c-hanging-braces-alist to control the automatic newlines used for
4142 anonymous classes.
4143
4144 *** Support for the Pike language added, along with new Pike specific
4145 syntactic symbols: inlambda, lambda-intro-cont
4146
4147 *** Support for Java anonymous classes via new syntactic symbol
4148 inexpr-class. New syntactic symbol inexpr-statement for Pike
4149 support and gcc-style statements inside expressions. New lineup
4150 function c-lineup-inexpr-block.
4151
4152 *** New syntactic symbol brace-entry-open which is used in brace lists
4153 (i.e. static initializers) when a list entry starts with an open
4154 brace. These used to be recognized as brace-list-entry's.
4155 c-electric-brace also recognizes brace-entry-open braces
4156 (brace-list-entry's can no longer be electrified).
4157
4158 *** New command c-indent-line-or-region, not bound by default.
4159
4160 *** `#' is only electric when typed in the indentation of a line.
4161
4162 *** Parentheses are now electric (via the new command c-electric-paren)
4163 for auto-reindenting lines when parens are typed.
4164
4165 *** In "gnu" style, inline-open offset is now set to zero.
4166
4167 *** Uniform handling of the inclass syntactic symbol. The indentation
4168 associated with it is now always relative to the class opening brace.
4169 This means that the indentation behavior has changed in some
4170 circumstances, but only if you've put anything besides 0 on the
4171 class-open syntactic symbol (none of the default styles do that).
4172
4173 ** Gnus changes.
4174
4175 *** New functionality for using Gnus as an offline newsreader has been
4176 added. A plethora of new commands and modes have been added. See the
4177 Gnus manual for the full story.
4178
4179 *** The nndraft backend has returned, but works differently than
4180 before. All Message buffers are now also articles in the nndraft
4181 group, which is created automatically.
4182
4183 *** `gnus-alter-header-function' can now be used to alter header
4184 values.
4185
4186 *** `gnus-summary-goto-article' now accept Message-ID's.
4187
4188 *** A new Message command for deleting text in the body of a message
4189 outside the region: `C-c C-v'.
4190
4191 *** You can now post to component group in nnvirtual groups with
4192 `C-u C-c C-c'.
4193
4194 *** `nntp-rlogin-program' -- new variable to ease customization.
4195
4196 *** `C-u C-c C-c' in `gnus-article-edit-mode' will now inhibit
4197 re-highlighting of the article buffer.
4198
4199 *** New element in `gnus-boring-article-headers' -- `long-to'.
4200
4201 *** `M-i' symbolic prefix command. See the section "Symbolic
4202 Prefixes" in the Gnus manual for details.
4203
4204 *** `L' and `I' in the summary buffer now take the symbolic prefix
4205 `a' to add the score rule to the "all.SCORE" file.
4206
4207 *** `gnus-simplify-subject-functions' variable to allow greater
4208 control over simplification.
4209
4210 *** `A T' -- new command for fetching the current thread.
4211
4212 *** `/ T' -- new command for including the current thread in the
4213 limit.
4214
4215 *** `M-RET' is a new Message command for breaking cited text.
4216
4217 *** \\1-expressions are now valid in `nnmail-split-methods'.
4218
4219 *** The `custom-face-lookup' function has been removed.
4220 If you used this function in your initialization files, you must
4221 rewrite them to use `face-spec-set' instead.
4222
4223 *** Cancelling now uses the current select method. Symbolic prefix
4224 `a' forces normal posting method.
4225
4226 *** New command to translate M******** sm*rtq**t*s into proper text
4227 -- `W d'.
4228
4229 *** For easier debugging of nntp, you can set `nntp-record-commands'
4230 to a non-nil value.
4231
4232 *** nntp now uses ~/.authinfo, a .netrc-like file, for controlling
4233 where and how to send AUTHINFO to NNTP servers.
4234
4235 *** A command for editing group parameters from the summary buffer
4236 has been added.
4237
4238 *** A history of where mails have been split is available.
4239
4240 *** A new article date command has been added -- `article-date-iso8601'.
4241
4242 *** Subjects can be simplified when threading by setting
4243 `gnus-score-thread-simplify'.
4244
4245 *** A new function for citing in Message has been added --
4246 `message-cite-original-without-signature'.
4247
4248 *** `article-strip-all-blank-lines' -- new article command.
4249
4250 *** A new Message command to kill to the end of the article has
4251 been added.
4252
4253 *** A minimum adaptive score can be specified by using the
4254 `gnus-adaptive-word-minimum' variable.
4255
4256 *** The "lapsed date" article header can be kept continually
4257 updated by the `gnus-start-date-timer' command.
4258
4259 *** Web listserv archives can be read with the nnlistserv backend.
4260
4261 *** Old dejanews archives can now be read by nnweb.
4262
4263 *** `gnus-posting-styles' has been re-activated.
4264
4265 ** Changes to TeX and LaTeX mode
4266
4267 *** The new variable `tex-start-options-string' can be used to give
4268 options for the TeX run. The default value causes TeX to run in
4269 nonstopmode. For an interactive TeX run set it to nil or "".
4270
4271 *** The command `tex-feed-input' sends input to the Tex Shell. In a
4272 TeX buffer it is bound to the keys C-RET, C-c RET, and C-c C-m (some
4273 of these keys may not work on all systems). For instance, if you run
4274 TeX interactively and if the TeX run stops because of an error, you
4275 can continue it without leaving the TeX buffer by typing C-RET.
4276
4277 *** The Tex Shell Buffer is now in `compilation-shell-minor-mode'.
4278 All error-parsing commands of the Compilation major mode are available
4279 but bound to keys that don't collide with the shell. Thus you can use
4280 the Tex Shell for command line executions like a usual shell.
4281
4282 *** The commands `tex-validate-region' and `tex-validate-buffer' check
4283 the matching of braces and $'s. The errors are listed in a *Occur*
4284 buffer and you can use C-c C-c or mouse-2 to go to a particular
4285 mismatch.
4286
4287 ** Changes to RefTeX mode
4288
4289 *** The table of contents buffer can now also display labels and
4290 file boundaries in addition to sections. Use `l', `i', and `c' keys.
4291
4292 *** Labels derived from context (the section heading) are now
4293 lowercase by default. To make the label legal in LaTeX, latin-1
4294 characters will lose their accent. All Mule characters will be
4295 removed from the label.
4296
4297 *** The automatic display of cross reference information can also use
4298 a window instead of the echo area. See variable `reftex-auto-view-crossref'.
4299
4300 *** kpsewhich can be used by RefTeX to find TeX and BibTeX files. See the
4301 customization group `reftex-finding-files'.
4302
4303 *** The option `reftex-bibfile-ignore-list' has been renamed to
4304 `reftex-bibfile-ignore-regexps' and indeed can be fed with regular
4305 expressions.
4306
4307 *** Multiple Selection buffers are now hidden buffers.
4308
4309 ** New/deleted modes and packages
4310
4311 *** The package snmp-mode.el provides major modes for editing SNMP and
4312 SNMPv2 MIBs. It has entries on `auto-mode-alist'.
4313
4314 *** The package sql.el provides a major mode, M-x sql-mode, for
4315 editing SQL files, and M-x sql-interactive-mode for interacting with
4316 SQL interpreters. It has an entry on `auto-mode-alist'.
4317
4318 *** M-x highlight-changes-mode provides a minor mode displaying buffer
4319 changes with a special face.
4320
4321 *** ispell4.el has been deleted. It got in the way of ispell.el and
4322 this was hard to fix reliably. It has long been obsolete -- use
4323 Ispell 3.1 and ispell.el.
4324 \f
4325 * MS-DOS changes in Emacs 20.4
4326
4327 ** Emacs compiled for MS-DOS now supports MULE features better.
4328 This includes support for display of all ISO 8859-N character sets,
4329 conversion to and from IBM codepage encoding of non-ASCII characters,
4330 and automatic setup of the MULE environment at startup. For details,
4331 check out the section `MS-DOS and MULE' in the manual.
4332
4333 The MS-DOS installation procedure automatically configures and builds
4334 Emacs with input method support if it finds an unpacked Leim
4335 distribution when the config.bat script is run.
4336
4337 ** Formerly, the value of lpr-command did not affect printing on
4338 MS-DOS unless print-region-function was set to nil, but now it
4339 controls whether an external program is invoked or output is written
4340 directly to a printer port. Similarly, in the previous version of
4341 Emacs, the value of ps-lpr-command did not affect PostScript printing
4342 on MS-DOS unless ps-printer-name was set to something other than a
4343 string (eg. t or `pipe'), but now it controls whether an external
4344 program is used. (These changes were made so that configuration of
4345 printing variables would be almost identical across all platforms.)
4346
4347 ** In the previous version of Emacs, PostScript and non-PostScript
4348 output was piped to external programs, but because most print programs
4349 available for MS-DOS and MS-Windows cannot read data from their standard
4350 input, on those systems the data to be output is now written to a
4351 temporary file whose name is passed as the last argument to the external
4352 program.
4353
4354 An exception is made for `print', a standard program on Windows NT,
4355 and `nprint', a standard program on Novell Netware. For both of these
4356 programs, the command line is constructed in the appropriate syntax
4357 automatically, using only the value of printer-name or ps-printer-name
4358 as appropriate--the value of the relevant `-switches' variable is
4359 ignored, as both programs have no useful switches.
4360
4361 ** The value of the variable dos-printer (cf. dos-ps-printer), if it has
4362 a value, overrides the value of printer-name (cf. ps-printer-name), on
4363 MS-DOS and MS-Windows only. This has been true since version 20.3, but
4364 was not documented clearly before.
4365
4366 ** All the Emacs games now work on MS-DOS terminals.
4367 This includes Tetris and Snake.
4368 \f
4369 * Lisp changes in Emacs 20.4
4370
4371 ** New functions line-beginning-position and line-end-position
4372 return the position of the beginning or end of the current line.
4373 They both accept an optional argument, which has the same
4374 meaning as the argument to beginning-of-line or end-of-line.
4375
4376 ** find-file and allied functions now have an optional argument
4377 WILDCARD. If this is non-nil, they do wildcard processing,
4378 and visit all files that match the wildcard pattern.
4379
4380 ** Changes in the file-attributes function.
4381
4382 *** The file size returned by file-attributes may be an integer or a float.
4383 It is an integer if the size fits in a Lisp integer, float otherwise.
4384
4385 *** The inode number returned by file-attributes may be an integer (if
4386 the number fits in a Lisp integer) or a cons cell containing two
4387 integers.
4388
4389 ** The new function directory-files-and-attributes returns a list of
4390 files in a directory and their attributes. It accepts the same
4391 arguments as directory-files and has similar semantics, except that
4392 file names and attributes are returned.
4393
4394 ** The new function file-attributes-lessp is a helper function for
4395 sorting the list generated by directory-files-and-attributes. It
4396 accepts two arguments, each a list of a file name and its atttributes.
4397 It compares the file names of each according to string-lessp and
4398 returns the result.
4399
4400 ** The new function file-expand-wildcards expands a wildcard-pattern
4401 to produce a list of existing files that match the pattern.
4402
4403 ** New functions for base64 conversion:
4404
4405 The function base64-encode-region converts a part of the buffer
4406 into the base64 code used in MIME. base64-decode-region
4407 performs the opposite conversion. Line-breaking is supported
4408 optionally.
4409
4410 Functions base64-encode-string and base64-decode-string do a similar
4411 job on the text in a string. They return the value as a new string.
4412
4413 **
4414 The new function process-running-child-p
4415 will tell you if a subprocess has given control of its
4416 terminal to its own child process.
4417
4418 ** interrupt-process and such functions have a new feature:
4419 when the second argument is `lambda', they send a signal
4420 to the running child of the subshell, if any, but if the shell
4421 itself owns its terminal, no signal is sent.
4422
4423 ** There are new widget types `plist' and `alist' which can
4424 be used for customizing variables whose values are plists or alists.
4425
4426 ** easymenu.el Now understands `:key-sequence' and `:style button'.
4427 :included is an alias for :visible.
4428
4429 easy-menu-add-item now understands the values returned by
4430 easy-menu-remove-item and easy-menu-item-present-p. This can be used
4431 to move or copy menu entries.
4432
4433 ** Multibyte editing changes
4434
4435 *** The definitions of sref and char-bytes are changed. Now, sref is
4436 an alias of aref and char-bytes always returns 1. This change is to
4437 make some Emacs Lisp code which works on 20.2 and earlier also
4438 work on the latest Emacs. Such code uses a combination of sref and
4439 char-bytes in a loop typically as below:
4440 (setq char (sref str idx)
4441 idx (+ idx (char-bytes idx)))
4442 The byte-compiler now warns that this is obsolete.
4443
4444 If you want to know how many bytes a specific multibyte character
4445 (say, CH) occupies in a multibyte buffer, use this code:
4446 (charset-bytes (char-charset ch))
4447
4448 *** In multibyte mode, when you narrow a buffer to some region, and the
4449 region is preceded or followed by non-ASCII codes, inserting or
4450 deleting at the head or the end of the region may signal this error:
4451
4452 Byte combining across boundary of accessible buffer text inhibitted
4453
4454 This is to avoid some bytes being combined together into a character
4455 across the boundary.
4456
4457 *** The functions find-charset-region and find-charset-string include
4458 `unknown' in the returned list in the following cases:
4459 o The current buffer or the target string is unibyte and
4460 contains 8-bit characters.
4461 o The current buffer or the target string is multibyte and
4462 contains invalid characters.
4463
4464 *** The functions decode-coding-region and encode-coding-region remove
4465 text properties of the target region. Ideally, they should correctly
4466 preserve text properties, but for the moment, it's hard. Removing
4467 text properties is better than preserving them in a less-than-correct
4468 way.
4469
4470 *** prefer-coding-system sets EOL conversion of default coding systems.
4471 If the argument to prefer-coding-system specifies a certain type of
4472 end of line conversion, the default coding systems set by
4473 prefer-coding-system will specify that conversion type for end of line.
4474
4475 *** The new function thai-compose-string can be used to properly
4476 compose Thai characters in a string.
4477
4478 ** The primitive `define-prefix-command' now takes an optional third
4479 argument NAME, which should be a string. It supplies the menu name
4480 for the created keymap. Keymaps created in order to be displayed as
4481 menus should always use the third argument.
4482
4483 ** The meanings of optional second arguments for read-char,
4484 read-event, and read-char-exclusive are flipped. Now the second
4485 arguments are INHERIT-INPUT-METHOD. These functions use the current
4486 input method (if any) if and only if INHERIT-INPUT-METHOD is non-nil.
4487
4488 ** The new function clear-this-command-keys empties out the contents
4489 of the vector that (this-command-keys) returns. This is useful in
4490 programs that read passwords, to prevent the passwords from echoing
4491 inadvertently as part of the next command in certain cases.
4492
4493 ** The new macro `with-temp-message' displays a temporary message in
4494 the echo area, while executing some Lisp code. Like `progn', it
4495 returns the value of the last form, but it also restores the previous
4496 echo area contents.
4497
4498 (with-temp-message MESSAGE &rest BODY)
4499
4500 ** The function `require' now takes an optional third argument
4501 NOERROR. If it is non-nil, then there is no error if the
4502 requested feature cannot be loaded.
4503
4504 ** In the function modify-face, an argument of (nil) for the
4505 foreground color, background color or stipple pattern
4506 means to clear out that attribute.
4507
4508 ** The `outer-window-id' frame property of an X frame
4509 gives the window number of the outermost X window for the frame.
4510
4511 ** Temporary buffers made with with-output-to-temp-buffer are now
4512 read-only by default, and normally use the major mode Help mode
4513 unless you put them in some other non-Fundamental mode before the
4514 end of with-output-to-temp-buffer.
4515
4516 ** The new functions gap-position and gap-size return information on
4517 the gap of the current buffer.
4518
4519 ** The new functions position-bytes and byte-to-position provide a way
4520 to convert between character positions and byte positions in the
4521 current buffer.
4522
4523 ** vc.el defines two new macros, `edit-vc-file' and `with-vc-file', to
4524 facilitate working with version-controlled files from Lisp programs.
4525 These macros check out a given file automatically if needed, and check
4526 it back in after any modifications have been made.
4527 \f
4528 * Installation Changes in Emacs 20.3
4529
4530 ** The default value of load-path now includes most subdirectories of
4531 the site-specific directories /usr/local/share/emacs/site-lisp and
4532 /usr/local/share/emacs/VERSION/site-lisp, in addition to those
4533 directories themselves. Both immediate subdirectories and
4534 subdirectories multiple levels down are added to load-path.
4535
4536 Not all subdirectories are included, though. Subdirectories whose
4537 names do not start with a letter or digit are excluded.
4538 Subdirectories named RCS or CVS are excluded. Also, a subdirectory
4539 which contains a file named `.nosearch' is excluded. You can use
4540 these methods to prevent certain subdirectories from being searched.
4541
4542 Emacs finds these subdirectories and adds them to load-path when it
4543 starts up. While it would be cleaner to find the subdirectories each
4544 time Emacs loads a file, that would be much slower.
4545
4546 This feature is an incompatible change. If you have stored some Emacs
4547 Lisp files in a subdirectory of the site-lisp directory specifically
4548 to prevent them from being used, you will need to rename the
4549 subdirectory to start with a non-alphanumeric character, or create a
4550 `.nosearch' file in it, in order to continue to achieve the desired
4551 results.
4552
4553 ** Emacs no longer includes an old version of the C preprocessor from
4554 GCC. This was formerly used to help compile Emacs with C compilers
4555 that had limits on the significant length of an identifier, but in
4556 fact we stopped supporting such compilers some time ago.
4557 \f
4558 * Changes in Emacs 20.3
4559
4560 ** The new command C-x z (repeat) repeats the previous command
4561 including its argument. If you repeat the z afterward,
4562 it repeats the command additional times; thus, you can
4563 perform many repetitions with one keystroke per repetition.
4564
4565 ** Emacs now supports "selective undo" which undoes only within a
4566 specified region. To do this, set point and mark around the desired
4567 region and type C-u C-x u (or C-u C-_). You can then continue undoing
4568 further, within the same region, by repeating the ordinary undo
4569 command C-x u or C-_. This will keep undoing changes that were made
4570 within the region you originally specified, until either all of them
4571 are undone, or it encounters a change which crosses the edge of that
4572 region.
4573
4574 In Transient Mark mode, undoing when a region is active requests
4575 selective undo.
4576
4577 ** If you specify --unibyte when starting Emacs, then all buffers are
4578 unibyte, except when a Lisp program specifically creates a multibyte
4579 buffer. Setting the environment variable EMACS_UNIBYTE has the same
4580 effect. The --no-unibyte option overrides EMACS_UNIBYTE and directs
4581 Emacs to run normally in multibyte mode.
4582
4583 The option --unibyte does not affect the reading of Emacs Lisp files,
4584 though. If you want a Lisp file to be read in unibyte mode, use
4585 -*-unibyte: t;-*- on its first line. That will force Emacs to
4586 load that file in unibyte mode, regardless of how Emacs was started.
4587
4588 ** toggle-enable-multibyte-characters no longer has a key binding and
4589 no longer appears in the menu bar. We've realized that changing the
4590 enable-multibyte-characters variable in an existing buffer is
4591 something that most users not do.
4592
4593 ** You can specify a coding system to use for the next cut or paste
4594 operations through the window system with the command C-x RET X.
4595 The coding system can make a difference for communication with other
4596 applications.
4597
4598 C-x RET x specifies a coding system for all subsequent cutting and
4599 pasting operations.
4600
4601 ** You can specify the printer to use for commands that do printing by
4602 setting the variable `printer-name'. Just what a printer name looks
4603 like depends on your operating system. You can specify a different
4604 printer for the Postscript printing commands by setting
4605 `ps-printer-name'.
4606
4607 ** Emacs now supports on-the-fly spell checking by the means of a
4608 minor mode. It is called M-x flyspell-mode. You don't have to remember
4609 any other special commands to use it, and you will hardly notice it
4610 except when you make a spelling error. Flyspell works by highlighting
4611 incorrect words as soon as they are completed or as soon as the cursor
4612 hits a new word.
4613
4614 Flyspell mode works with whichever dictionary you have selected for
4615 Ispell in Emacs. In TeX mode, it understands TeX syntax so as not
4616 to be confused by TeX commands.
4617
4618 You can correct a misspelled word by editing it into something
4619 correct. You can also correct it, or accept it as correct, by
4620 clicking on the word with Mouse-2; that gives you a pop-up menu
4621 of various alternative replacements and actions.
4622
4623 Flyspell mode also proposes "automatic" corrections. M-TAB replaces
4624 the current misspelled word with a possible correction. If several
4625 corrections are made possible, M-TAB cycles through them in
4626 alphabetical order, or in order of decreasing likelihood if
4627 flyspell-sort-corrections is nil.
4628
4629 Flyspell mode also flags an error when a word is repeated, if
4630 flyspell-mark-duplications-flag is non-nil.
4631
4632 ** Changes in input method usage.
4633
4634 Now you can use arrow keys (right, left, down, up) for selecting among
4635 the alternatives just the same way as you do by C-f, C-b, C-n, and C-p
4636 respectively.
4637
4638 You can use the ENTER key to accept the current conversion.
4639
4640 If you type TAB to display a list of alternatives, you can select one
4641 of the alternatives with Mouse-2.
4642
4643 The meaning of the variable `input-method-verbose-flag' is changed so
4644 that you can set it to t, nil, `default', or `complex-only'.
4645
4646 If the value is nil, extra guidance is never given.
4647
4648 If the value is t, extra guidance is always given.
4649
4650 If the value is `complex-only', extra guidance is always given only
4651 when you are using complex input methods such as chinese-py.
4652
4653 If the value is `default' (this is the default), extra guidance is
4654 given in the following case:
4655 o When you are using a complex input method.
4656 o When you are using a simple input method but not in the minibuffer.
4657
4658 If you are using Emacs through a very slow line, setting
4659 input-method-verbose-flag to nil or to complex-only is a good choice,
4660 and if you are using an input method you are not familiar with,
4661 setting it to t is helpful.
4662
4663 The old command select-input-method is now called set-input-method.
4664
4665 In the language environment "Korean", you can use the following
4666 keys:
4667 Shift-SPC toggle-korean-input-method
4668 C-F9 quail-hangul-switch-symbol-ksc
4669 F9 quail-hangul-switch-hanja
4670 These key bindings are canceled when you switch to another language
4671 environment.
4672
4673 ** The minibuffer history of file names now records the specified file
4674 names, not the entire minibuffer input. For example, if the
4675 minibuffer starts out with /usr/foo/, you might type in /etc/passwd to
4676 get
4677
4678 /usr/foo//etc/passwd
4679
4680 which stands for the file /etc/passwd.
4681
4682 Formerly, this used to put /usr/foo//etc/passwd in the history list.
4683 Now this puts just /etc/passwd in the history list.
4684
4685 ** If you are root, Emacs sets backup-by-copying-when-mismatch to t
4686 at startup, so that saving a file will be sure to preserve
4687 its owner and group.
4688
4689 ** find-func.el can now also find the place of definition of Emacs
4690 Lisp variables in user-loaded libraries.
4691
4692 ** C-x r t (string-rectangle) now deletes the existing rectangle
4693 contents before inserting the specified string on each line.
4694
4695 ** There is a new command delete-whitespace-rectangle
4696 which deletes whitespace starting from a particular column
4697 in all the lines on a rectangle. The column is specified
4698 by the left edge of the rectangle.
4699
4700 ** You can now store a number into a register with C-u NUMBER C-x r n REG,
4701 increment it by INC with C-u INC C-x r + REG (to increment by one, omit
4702 C-u INC), and insert it in the buffer with C-x r g REG. This is useful
4703 for writing keyboard macros.
4704
4705 ** The new command M-x speedbar displays a frame in which directories,
4706 files, and tags can be displayed, manipulated, and jumped to. The
4707 frame defaults to 20 characters in width, and is the same height as
4708 the frame that it was started from. Some major modes define
4709 additional commands for the speedbar, including Rmail, GUD/GDB, and
4710 info.
4711
4712 ** query-replace-regexp is now bound to C-M-%.
4713
4714 ** In Transient Mark mode, when the region is active, M-x
4715 query-replace and the other replace commands now operate on the region
4716 contents only.
4717
4718 ** M-x write-region, when used interactively, now asks for
4719 confirmation before overwriting an existing file. When you call
4720 the function from a Lisp program, a new optional argument CONFIRM
4721 says whether to ask for confirmation in this case.
4722
4723 ** If you use find-file-literally and the file is already visited
4724 non-literally, the command asks you whether to revisit the file
4725 literally. If you say no, it signals an error.
4726
4727 ** Major modes defined with the "derived mode" feature
4728 now use the proper name for the mode hook: WHATEVER-mode-hook.
4729 Formerly they used the name WHATEVER-mode-hooks, but that is
4730 inconsistent with Emacs conventions.
4731
4732 ** shell-command-on-region (and shell-command) reports success or
4733 failure if the command produces no output.
4734
4735 ** Set focus-follows-mouse to nil if your window system or window
4736 manager does not transfer focus to another window when you just move
4737 the mouse.
4738
4739 ** mouse-menu-buffer-maxlen has been renamed to
4740 mouse-buffer-menu-maxlen to be consistent with the other related
4741 function and variable names.
4742
4743 ** The new variable auto-coding-alist specifies coding systems for
4744 reading specific files. This has higher priority than
4745 file-coding-system-alist.
4746
4747 ** If you set the variable unibyte-display-via-language-environment to
4748 t, then Emacs displays non-ASCII characters are displayed by
4749 converting them to the equivalent multibyte characters according to
4750 the current language environment. As a result, they are displayed
4751 according to the current fontset.
4752
4753 ** C-q's handling of codes in the range 0200 through 0377 is changed.
4754
4755 The codes in the range 0200 through 0237 are inserted as one byte of
4756 that code regardless of the values of nonascii-translation-table and
4757 nonascii-insert-offset.
4758
4759 For the codes in the range 0240 through 0377, if
4760 enable-multibyte-characters is non-nil and nonascii-translation-table
4761 nor nonascii-insert-offset can't convert them to valid multibyte
4762 characters, they are converted to Latin-1 characters.
4763
4764 ** If you try to find a file that is not read-accessible, you now get
4765 an error, rather than an empty buffer and a warning.
4766
4767 ** In the minibuffer history commands M-r and M-s, an upper case
4768 letter in the regular expression forces case-sensitive search.
4769
4770 ** In the *Help* buffer, cross-references to commands and variables
4771 are inferred and hyperlinked. Use C-h m in Help mode for the relevant
4772 command keys.
4773
4774 ** M-x apropos-command, with a prefix argument, no longer looks for
4775 user option variables--instead it looks for noninteractive functions.
4776
4777 Meanwhile, the command apropos-variable normally searches for
4778 user option variables; with a prefix argument, it looks at
4779 all variables that have documentation.
4780
4781 ** When you type a long line in the minibuffer, and the minibuffer
4782 shows just one line, automatically scrolling works in a special way
4783 that shows you overlap with the previous line of text. The variable
4784 minibuffer-scroll-overlap controls how many characters of overlap
4785 it should show; the default is 20.
4786
4787 Meanwhile, Resize Minibuffer mode is still available; in that mode,
4788 the minibuffer grows taller (up to a point) as needed to show the whole
4789 of your input.
4790
4791 ** The new command M-x customize-changed-options lets you customize
4792 all the options whose meanings or default values have changed in
4793 recent Emacs versions. You specify a previous Emacs version number as
4794 argument, and the command creates a customization buffer showing all
4795 the customizable options which were changed since that version.
4796 Newly added options are included as well.
4797
4798 If you don't specify a particular version number argument,
4799 then the customization buffer shows all the customizable options
4800 for which Emacs versions of changes are recorded.
4801
4802 This function is also bound to the Changed Options entry in the
4803 Customize menu.
4804
4805 ** When you run M-x grep with a prefix argument, it figures out
4806 the tag around point and puts that into the default grep command.
4807
4808 ** The new command M-* (pop-tag-mark) pops back through a history of
4809 buffer positions from which M-. or other tag-finding commands were
4810 invoked.
4811
4812 ** The new variable comment-padding specifies the number of spaces
4813 that `comment-region' will insert before the actual text of the comment.
4814 The default is 1.
4815
4816 ** In Fortran mode the characters `.', `_' and `$' now have symbol
4817 syntax, not word syntax. Fortran mode now supports `imenu' and has
4818 new commands fortran-join-line (M-^) and fortran-narrow-to-subprogram
4819 (C-x n d). M-q can be used to fill a statement or comment block
4820 sensibly.
4821
4822 ** GUD now supports jdb, the Java debugger, and pdb, the Python debugger.
4823
4824 ** If you set the variable add-log-keep-changes-together to a non-nil
4825 value, the command `C-x 4 a' will automatically notice when you make
4826 two entries in one day for one file, and combine them.
4827
4828 ** You can use the command M-x diary-mail-entries to mail yourself a
4829 reminder about upcoming diary entries. See the documentation string
4830 for a sample shell script for calling this function automatically
4831 every night.
4832
4833 ** Desktop changes
4834
4835 *** All you need to do to enable use of the Desktop package, is to set
4836 the variable desktop-enable to t with Custom.
4837
4838 *** Minor modes are now restored. Which minor modes are restored
4839 and how modes are restored is controlled by `desktop-minor-mode-table'.
4840
4841 ** There is no need to do anything special, now, to enable Gnus to
4842 read and post multi-lingual articles.
4843
4844 ** Outline mode has now support for showing hidden outlines when
4845 doing an isearch. In order for this to happen search-invisible should
4846 be set to open (the default). If an isearch match is inside a hidden
4847 outline the outline is made visible. If you continue pressing C-s and
4848 the match moves outside the formerly invisible outline, the outline is
4849 made invisible again.
4850
4851 ** Mail reading and sending changes
4852
4853 *** The Rmail e command now switches to displaying the whole header of
4854 the message before it lets you edit the message. This is so that any
4855 changes you make in the header will not be lost if you subsequently
4856 toggle.
4857
4858 *** The w command in Rmail, which writes the message body into a file,
4859 now works in the summary buffer as well. (The command to delete the
4860 summary buffer is now Q.) The default file name for the w command, if
4861 the message has no subject, is stored in the variable
4862 rmail-default-body-file.
4863
4864 *** Most of the commands and modes that operate on mail and netnews no
4865 longer depend on the value of mail-header-separator. Instead, they
4866 handle whatever separator the buffer happens to use.
4867
4868 *** If you set mail-signature to a value which is not t, nil, or a string,
4869 it should be an expression. When you send a message, this expression
4870 is evaluated to insert the signature.
4871
4872 *** The new Lisp library feedmail.el (version 8) enhances processing of
4873 outbound email messages. It works in coordination with other email
4874 handling packages (e.g., rmail, VM, gnus) and is responsible for
4875 putting final touches on messages and actually submitting them for
4876 transmission. Users of the emacs program "fakemail" might be
4877 especially interested in trying feedmail.
4878
4879 feedmail is not enabled by default. See comments at the top of
4880 feedmail.el for set-up instructions. Among the bigger features
4881 provided by feedmail are:
4882
4883 **** you can park outgoing messages into a disk-based queue and
4884 stimulate sending some or all of them later (handy for laptop users);
4885 there is also a queue for draft messages
4886
4887 **** you can get one last look at the prepped outbound message and
4888 be prompted for confirmation
4889
4890 **** does smart filling of address headers
4891
4892 **** can generate a MESSAGE-ID: line and a DATE: line; the date can be
4893 the time the message was written or the time it is being sent; this
4894 can make FCC copies more closely resemble copies that recipients get
4895
4896 **** you can specify an arbitrary function for actually transmitting
4897 the message; included in feedmail are interfaces for /bin/[r]mail,
4898 /usr/lib/sendmail, and elisp smtpmail; it's easy to write a new
4899 function for something else (10-20 lines of elisp)
4900
4901 ** Dired changes
4902
4903 *** The Dired function dired-do-toggle, which toggles marked and unmarked
4904 files, is now bound to "t" instead of "T".
4905
4906 *** dired-at-point has been added to ffap.el. It allows one to easily
4907 run Dired on the directory name at point.
4908
4909 *** Dired has a new command: %g. It searches the contents of
4910 files in the directory and marks each file that contains a match
4911 for a specified regexp.
4912
4913 ** VC Changes
4914
4915 *** New option vc-ignore-vc-files lets you turn off version control
4916 conveniently.
4917
4918 *** VC Dired has been completely rewritten. It is now much
4919 faster, especially for CVS, and works very similar to ordinary
4920 Dired.
4921
4922 VC Dired is invoked by typing C-x v d and entering the name of the
4923 directory to display. By default, VC Dired gives you a recursive
4924 listing of all files at or below the given directory which are
4925 currently locked (for CVS, all files not up-to-date are shown).
4926
4927 You can change the listing format by setting vc-dired-recurse to nil,
4928 then it shows only the given directory, and you may also set
4929 vc-dired-terse-display to nil, then it shows all files under version
4930 control plus the names of any subdirectories, so that you can type `i'
4931 on such lines to insert them manually, as in ordinary Dired.
4932
4933 All Dired commands operate normally in VC Dired, except for `v', which
4934 is redefined as the version control prefix. That means you may type
4935 `v l', `v =' etc. to invoke `vc-print-log', `vc-diff' and the like on
4936 the file named in the current Dired buffer line. `v v' invokes
4937 `vc-next-action' on this file, or on all files currently marked.
4938
4939 The new command `v t' (vc-dired-toggle-terse-mode) allows you to
4940 toggle between terse display (only locked files) and full display (all
4941 VC files plus subdirectories). There is also a special command,
4942 `* l', to mark all files currently locked.
4943
4944 Giving a prefix argument to C-x v d now does the same thing as in
4945 ordinary Dired: it allows you to supply additional options for the ls
4946 command in the minibuffer, to fine-tune VC Dired's output.
4947
4948 *** Under CVS, if you merge changes from the repository into a working
4949 file, and CVS detects conflicts, VC now offers to start an ediff
4950 session to resolve them.
4951
4952 Alternatively, you can use the new command `vc-resolve-conflicts' to
4953 resolve conflicts in a file at any time. It works in any buffer that
4954 contains conflict markers as generated by rcsmerge (which is what CVS
4955 uses as well).
4956
4957 *** You can now transfer changes between branches, using the new
4958 command vc-merge (C-x v m). It is implemented for RCS and CVS. When
4959 you invoke it in a buffer under version-control, you can specify
4960 either an entire branch or a pair of versions, and the changes on that
4961 branch or between the two versions are merged into the working file.
4962 If this results in any conflicts, they may be resolved interactively,
4963 using ediff.
4964
4965 ** Changes in Font Lock
4966
4967 *** The face and variable previously known as font-lock-reference-face
4968 are now called font-lock-constant-face to better reflect their typical
4969 use for highlighting constants and labels. (Its face properties are
4970 unchanged.) The variable font-lock-reference-face remains for now for
4971 compatibility reasons, but its value is font-lock-constant-face.
4972
4973 ** Frame name display changes
4974
4975 *** The command set-frame-name lets you set the name of the current
4976 frame. You can use the new command select-frame-by-name to select and
4977 raise a frame; this is mostly useful on character-only terminals, or
4978 when many frames are invisible or iconified.
4979
4980 *** On character-only terminal (not a window system), changing the
4981 frame name is now reflected on the mode line and in the Buffers/Frames
4982 menu.
4983
4984 ** Comint (subshell) changes
4985
4986 *** In Comint modes, the commands to kill, stop or interrupt a
4987 subjob now also kill pending input. This is for compatibility
4988 with ordinary shells, where the signal characters do this.
4989
4990 *** There are new commands in Comint mode.
4991
4992 C-c C-x fetches the "next" line from the input history;
4993 that is, the line after the last line you got.
4994 You can use this command to fetch successive lines, one by one.
4995
4996 C-c SPC accumulates lines of input. More precisely, it arranges to
4997 send the current line together with the following line, when you send
4998 the following line.
4999
5000 C-c C-a if repeated twice consecutively now moves to the process mark,
5001 which separates the pending input from the subprocess output and the
5002 previously sent input.
5003
5004 C-c M-r now runs comint-previous-matching-input-from-input;
5005 it searches for a previous command, using the current pending input
5006 as the search string.
5007
5008 *** New option compilation-scroll-output can be set to scroll
5009 automatically in compilation-mode windows.
5010
5011 ** C mode changes
5012
5013 *** Multiline macros are now handled, both as they affect indentation,
5014 and as recognized syntax. New syntactic symbol cpp-macro-cont is
5015 assigned to second and subsequent lines of a multiline macro
5016 definition.
5017
5018 *** A new style "user" which captures all non-hook-ified
5019 (i.e. top-level) .emacs file variable settings and customizations.
5020 Style "cc-mode" is an alias for "user" and is deprecated. "gnu"
5021 style is still the default however.
5022
5023 *** "java" style now conforms to Sun's JDK coding style.
5024
5025 *** There are new commands c-beginning-of-defun, c-end-of-defun which
5026 are alternatives which you could bind to C-M-a and C-M-e if you prefer
5027 them. They do not have key bindings by default.
5028
5029 *** New and improved implementations of M-a (c-beginning-of-statement)
5030 and M-e (c-end-of-statement).
5031
5032 *** C++ namespace blocks are supported, with new syntactic symbols
5033 namespace-open, namespace-close, and innamespace.
5034
5035 *** File local variable settings of c-file-style and c-file-offsets
5036 makes the style variables local to that buffer only.
5037
5038 *** New indentation functions c-lineup-close-paren,
5039 c-indent-one-line-block, c-lineup-dont-change.
5040
5041 *** Improvements (hopefully!) to the way CC Mode is loaded. You
5042 should now be able to do a (require 'cc-mode) to get the entire
5043 package loaded properly for customization in your .emacs file. A new
5044 variable c-initialize-on-load controls this and is t by default.
5045
5046 ** Changes to hippie-expand.
5047
5048 *** New customization variable `hippie-expand-dabbrev-skip-space'. If
5049 non-nil, trailing spaces may be included in the abbreviation to search for,
5050 which then gives the same behavior as the original `dabbrev-expand'.
5051
5052 *** New customization variable `hippie-expand-dabbrev-as-symbol'. If
5053 non-nil, characters of syntax '_' is considered part of the word when
5054 expanding dynamically.
5055
5056 *** New customization variable `hippie-expand-no-restriction'. If
5057 non-nil, narrowed buffers are widened before they are searched.
5058
5059 *** New customization variable `hippie-expand-only-buffers'. If
5060 non-empty, buffers searched are restricted to the types specified in
5061 this list. Useful for example when constructing new special-purpose
5062 expansion functions with `make-hippie-expand-function'.
5063
5064 *** Text properties of the expansion are no longer copied.
5065
5066 ** Changes in BibTeX mode.
5067
5068 *** Any titleword matching a regexp in the new variable
5069 bibtex-autokey-titleword-ignore (case sensitive) is ignored during
5070 automatic key generation. This replaces variable
5071 bibtex-autokey-titleword-first-ignore, which only checked for matches
5072 against the first word in the title.
5073
5074 *** Autokey generation now uses all words from the title, not just
5075 capitalized words. To avoid conflicts with existing customizations,
5076 bibtex-autokey-titleword-ignore is set up such that words starting with
5077 lowerkey characters will still be ignored. Thus, if you want to use
5078 lowercase words from the title, you will have to overwrite the
5079 bibtex-autokey-titleword-ignore standard setting.
5080
5081 *** Case conversion of names and title words for automatic key
5082 generation is more flexible. Variable bibtex-autokey-preserve-case is
5083 replaced by bibtex-autokey-titleword-case-convert and
5084 bibtex-autokey-name-case-convert.
5085
5086 ** Changes in vcursor.el.
5087
5088 *** Support for character terminals is available: there is a new keymap
5089 and the vcursor will appear as an arrow between buffer text. A
5090 variable `vcursor-interpret-input' allows input from the vcursor to be
5091 entered exactly as if typed. Numerous functions, including
5092 `vcursor-compare-windows', have been rewritten to improve consistency
5093 in the selection of windows and corresponding keymaps.
5094
5095 *** vcursor options can now be altered with M-x customize under the
5096 Editing group once the package is loaded.
5097
5098 *** Loading vcursor now does not define keys by default, as this is
5099 generally a bad side effect. Use M-x customize to set
5100 vcursor-key-bindings to t to restore the old behaviour.
5101
5102 *** vcursor-auto-disable can be `copy', which turns off copying from the
5103 vcursor, but doesn't disable it, after any non-vcursor command.
5104
5105 ** Ispell changes.
5106
5107 *** You can now spell check comments and strings in the current
5108 buffer with M-x ispell-comments-and-strings. Comments and strings
5109 are identified by syntax tables in effect.
5110
5111 *** Generic region skipping implemented.
5112 A single buffer can be broken into a number of regions where text will
5113 and will not be checked. The definitions of the regions can be user
5114 defined. New applications and improvements made available by this
5115 include:
5116
5117 o URLs are automatically skipped
5118 o EMail message checking is vastly improved.
5119
5120 *** Ispell can highlight the erroneous word even on non-window terminals.
5121
5122 ** Changes to RefTeX mode
5123
5124 RefTeX has been updated in order to make it more usable with very
5125 large projects (like a several volume math book). The parser has been
5126 re-written from scratch. To get maximum speed from RefTeX, check the
5127 section `Optimizations' in the manual.
5128
5129 *** New recursive parser.
5130
5131 The old version of RefTeX created a single large buffer containing the
5132 entire multifile document in order to parse the document. The new
5133 recursive parser scans the individual files.
5134
5135 *** Parsing only part of a document.
5136
5137 Reparsing of changed document parts can now be made faster by enabling
5138 partial scans. To use this feature, read the documentation string of
5139 the variable `reftex-enable-partial-scans' and set the variable to t.
5140
5141 (setq reftex-enable-partial-scans t)
5142
5143 *** Storing parsing information in a file.
5144
5145 This can improve startup times considerably. To turn it on, use
5146
5147 (setq reftex-save-parse-info t)
5148
5149 *** Using multiple selection buffers
5150
5151 If the creation of label selection buffers is too slow (this happens
5152 for large documents), you can reuse these buffers by setting
5153
5154 (setq reftex-use-multiple-selection-buffers t)
5155
5156 *** References to external documents.
5157
5158 The LaTeX package `xr' allows to cross-reference labels in external
5159 documents. RefTeX can provide information about the external
5160 documents as well. To use this feature, set up the \externaldocument
5161 macros required by the `xr' package and rescan the document with
5162 RefTeX. The external labels can then be accessed with the `x' key in
5163 the selection buffer provided by `reftex-reference' (bound to `C-c )').
5164 The `x' key also works in the table of contents buffer.
5165
5166 *** Many more labeled LaTeX environments are recognized by default.
5167
5168 The builtin command list now covers all the standard LaTeX commands,
5169 and all of the major packages included in the LaTeX distribution.
5170
5171 Also, RefTeX now understands the \appendix macro and changes
5172 the enumeration of sections in the *toc* buffer accordingly.
5173
5174 *** Mouse support for selection and *toc* buffers
5175
5176 The mouse can now be used to select items in the selection and *toc*
5177 buffers. See also the new option `reftex-highlight-selection'.
5178
5179 *** New keymaps for selection and table of contents modes.
5180
5181 The selection processes for labels and citation keys, and the table of
5182 contents buffer now have their own keymaps: `reftex-select-label-map',
5183 `reftex-select-bib-map', `reftex-toc-map'. The selection processes
5184 have a number of new keys predefined. In particular, TAB lets you
5185 enter a label with completion. Check the on-the-fly help (press `?'
5186 at the selection prompt) or read the Info documentation to find out
5187 more.
5188
5189 *** Support for the varioref package
5190
5191 The `v' key in the label selection buffer toggles \ref versus \vref.
5192
5193 *** New hooks
5194
5195 Three new hooks can be used to redefine the way labels, references,
5196 and citations are created. These hooks are
5197 `reftex-format-label-function', `reftex-format-ref-function',
5198 `reftex-format-cite-function'.
5199
5200 *** Citations outside LaTeX
5201
5202 The command `reftex-citation' may also be used outside LaTeX (e.g. in
5203 a mail buffer). See the Info documentation for details.
5204
5205 *** Short context is no longer fontified.
5206
5207 The short context in the label menu no longer copies the
5208 fontification from the text in the buffer. If you prefer it to be
5209 fontified, use
5210
5211 (setq reftex-refontify-context t)
5212
5213 ** file-cache-minibuffer-complete now accepts a prefix argument.
5214 With a prefix argument, it does not try to do completion of
5215 the file name within its directory; it only checks for other
5216 directories that contain the same file name.
5217
5218 Thus, given the file name Makefile, and assuming that a file
5219 Makefile.in exists in the same directory, ordinary
5220 file-cache-minibuffer-complete will try to complete Makefile to
5221 Makefile.in and will therefore never look for other directories that
5222 have Makefile. A prefix argument tells it not to look for longer
5223 names such as Makefile.in, so that instead it will look for other
5224 directories--just as if the name were already complete in its present
5225 directory.
5226
5227 ** New modes and packages
5228
5229 *** There is a new alternative major mode for Perl, Cperl mode.
5230 It has many more features than Perl mode, and some people prefer
5231 it, but some do not.
5232
5233 *** There is a new major mode, M-x vhdl-mode, for editing files of VHDL
5234 code.
5235
5236 *** M-x which-function-mode enables a minor mode that displays the
5237 current function name continuously in the mode line, as you move
5238 around in a buffer.
5239
5240 Which Function mode is effective in major modes which support Imenu.
5241
5242 *** Gametree is a major mode for editing game analysis trees. The author
5243 uses it for keeping notes about his postal Chess games, but it should
5244 be helpful for other two-player games as well, as long as they have an
5245 established system of notation similar to Chess.
5246
5247 *** The new minor mode checkdoc-minor-mode provides Emacs Lisp
5248 documentation string checking for style and spelling. The style
5249 guidelines are found in the Emacs Lisp programming manual.
5250
5251 *** The net-utils package makes some common networking features
5252 available in Emacs. Some of these functions are wrappers around
5253 system utilities (ping, nslookup, etc); others are implementations of
5254 simple protocols (finger, whois) in Emacs Lisp. There are also
5255 functions to make simple connections to TCP/IP ports for debugging and
5256 the like.
5257
5258 *** highlight-changes-mode is a minor mode that uses colors to
5259 identify recently changed parts of the buffer text.
5260
5261 *** The new package `midnight' lets you specify things to be done
5262 within Emacs at midnight--by default, kill buffers that you have not
5263 used in a considerable time. To use this feature, customize
5264 the user option `midnight-mode' to t.
5265
5266 *** The file generic-x.el defines a number of simple major modes.
5267
5268 apache-generic-mode: For Apache and NCSA httpd configuration files
5269 samba-generic-mode: Samba configuration files
5270 fvwm-generic-mode: For fvwm initialization files
5271 x-resource-generic-mode: For X resource files
5272 hosts-generic-mode: For hosts files (.rhosts, /etc/hosts, etc)
5273 mailagent-rules-generic-mode: For mailagent .rules files
5274 javascript-generic-mode: For JavaScript files
5275 vrml-generic-mode: For VRML files
5276 java-manifest-generic-mode: For Java MANIFEST files
5277 java-properties-generic-mode: For Java property files
5278 mailrc-generic-mode: For .mailrc files
5279
5280 Platform-specific modes:
5281
5282 prototype-generic-mode: For Solaris/Sys V prototype files
5283 pkginfo-generic-mode: For Solaris/Sys V pkginfo files
5284 alias-generic-mode: For C shell alias files
5285 inf-generic-mode: For MS-Windows INF files
5286 ini-generic-mode: For MS-Windows INI files
5287 reg-generic-mode: For MS-Windows Registry files
5288 bat-generic-mode: For MS-Windows BAT scripts
5289 rc-generic-mode: For MS-Windows Resource files
5290 rul-generic-mode: For InstallShield scripts
5291 \f
5292 * Lisp changes in Emacs 20.3 since the Emacs Lisp Manual was published
5293
5294 ** If you want a Lisp file to be read in unibyte mode,
5295 use -*-unibyte: t;-*- on its first line.
5296 That will force Emacs to read that file in unibyte mode.
5297 Otherwise, the file will be loaded and byte-compiled in multibyte mode.
5298
5299 Thus, each lisp file is read in a consistent way regardless of whether
5300 you started Emacs with --unibyte, so that a Lisp program gives
5301 consistent results regardless of how Emacs was started.
5302
5303 ** The new function assoc-default is useful for searching an alist,
5304 and using a default value if the key is not found there. You can
5305 specify a comparison predicate, so this function is useful for
5306 searching comparing a string against an alist of regular expressions.
5307
5308 ** The functions unibyte-char-to-multibyte and
5309 multibyte-char-to-unibyte convert between unibyte and multibyte
5310 character codes, in a way that is appropriate for the current language
5311 environment.
5312
5313 ** The functions read-event, read-char and read-char-exclusive now
5314 take two optional arguments. PROMPT, if non-nil, specifies a prompt
5315 string. SUPPRESS-INPUT-METHOD, if non-nil, says to disable the
5316 current input method for reading this one event.
5317
5318 ** Two new variables print-escape-nonascii and print-escape-multibyte
5319 now control whether to output certain characters as
5320 backslash-sequences. print-escape-nonascii applies to single-byte
5321 non-ASCII characters; print-escape-multibyte applies to multibyte
5322 characters. Both of these variables are used only when printing
5323 in readable fashion (prin1 uses them, princ does not).
5324 \f
5325 * Lisp changes in Emacs 20.3 before the Emacs Lisp Manual was published
5326
5327 ** Compiled Emacs Lisp files made with the modified "MBSK" version
5328 of Emacs 20.2 do not work in Emacs 20.3.
5329
5330 ** Buffer positions are now measured in characters, as they were
5331 in Emacs 19 and before. This means that (forward-char 1)
5332 always increases point by 1.
5333
5334 The function chars-in-region now just subtracts its arguments. It is
5335 considered obsolete. The function char-boundary-p has been deleted.
5336
5337 See below for additional changes relating to multibyte characters.
5338
5339 ** defcustom, defface and defgroup now accept the keyword `:version'.
5340 Use this to specify in which version of Emacs a certain variable's
5341 default value changed. For example,
5342
5343 (defcustom foo-max 34 "*Maximum number of foo's allowed."
5344 :type 'integer
5345 :group 'foo
5346 :version "20.3")
5347
5348 (defgroup foo-group nil "The foo group."
5349 :version "20.3")
5350
5351 If an entire new group is added or the variables in it have the
5352 default values changed, then just add a `:version' to that group. It
5353 is recommended that new packages added to the distribution contain a
5354 `:version' in the top level group.
5355
5356 This information is used to control the customize-changed-options command.
5357
5358 ** It is now an error to change the value of a symbol whose name
5359 starts with a colon--if it is interned in the standard obarray.
5360
5361 However, setting such a symbol to its proper value, which is that
5362 symbol itself, is not an error. This is for the sake of programs that
5363 support previous Emacs versions by explicitly setting these variables
5364 to themselves.
5365
5366 If you set the variable keyword-symbols-constant-flag to nil,
5367 this error is suppressed, and you can set these symbols to any
5368 values whatever.
5369
5370 ** There is a new debugger command, R.
5371 It evaluates an expression like e, but saves the result
5372 in the buffer *Debugger-record*.
5373
5374 ** Frame-local variables.
5375
5376 You can now make a variable local to various frames. To do this, call
5377 the function make-variable-frame-local; this enables frames to have
5378 local bindings for that variable.
5379
5380 These frame-local bindings are actually frame parameters: you create a
5381 frame-local binding in a specific frame by calling
5382 modify-frame-parameters and specifying the variable name as the
5383 parameter name.
5384
5385 Buffer-local bindings take precedence over frame-local bindings.
5386 Thus, if the current buffer has a buffer-local binding, that binding is
5387 active; otherwise, if the selected frame has a frame-local binding,
5388 that binding is active; otherwise, the default binding is active.
5389
5390 It would not be hard to implement window-local bindings, but it is not
5391 clear that this would be very useful; windows tend to come and go in a
5392 very transitory fashion, so that trying to produce any specific effect
5393 through a window-local binding would not be very robust.
5394
5395 ** `sregexq' and `sregex' are two new functions for constructing
5396 "symbolic regular expressions." These are Lisp expressions that, when
5397 evaluated, yield conventional string-based regexps. The symbolic form
5398 makes it easier to construct, read, and maintain complex patterns.
5399 See the documentation in sregex.el.
5400
5401 ** parse-partial-sexp's return value has an additional element which
5402 is used to pass information along if you pass it to another call to
5403 parse-partial-sexp, starting its scan where the first call ended.
5404 The contents of this field are not yet finalized.
5405
5406 ** eval-region now accepts a fourth optional argument READ-FUNCTION.
5407 If it is non-nil, that function is used instead of `read'.
5408
5409 ** unload-feature by default removes the feature's functions from
5410 known hooks to avoid trouble, but a package providing FEATURE can
5411 define a hook FEATURE-unload-hook to be run by unload-feature instead.
5412
5413 ** read-from-minibuffer no longer returns the argument DEFAULT-VALUE
5414 when the user enters empty input. It now returns the null string, as
5415 it did in Emacs 19. The default value is made available in the
5416 history via M-n, but it is not applied here as a default.
5417
5418 The other, more specialized minibuffer-reading functions continue to
5419 return the default value (not the null string) when the user enters
5420 empty input.
5421
5422 ** The new variable read-buffer-function controls which routine to use
5423 for selecting buffers. For example, if you set this variable to
5424 `iswitchb-read-buffer', iswitchb will be used to read buffer names.
5425 Other functions can also be used if they accept the same arguments as
5426 `read-buffer' and return the selected buffer name as a string.
5427
5428 ** The new function read-passwd reads a password from the terminal,
5429 echoing a period for each character typed. It takes three arguments:
5430 a prompt string, a flag which says "read it twice to make sure", and a
5431 default password to use if the user enters nothing.
5432
5433 ** The variable fill-nobreak-predicate gives major modes a way to
5434 specify not to break a line at certain places. Its value is a
5435 function which is called with no arguments, with point located at the
5436 place where a break is being considered. If the function returns
5437 non-nil, then the line won't be broken there.
5438
5439 ** window-end now takes an optional second argument, UPDATE.
5440 If this is non-nil, then the function always returns an accurate
5441 up-to-date value for the buffer position corresponding to the
5442 end of the window, even if this requires computation.
5443
5444 ** other-buffer now takes an optional argument FRAME
5445 which specifies which frame's buffer list to use.
5446 If it is nil, that means use the selected frame's buffer list.
5447
5448 ** The new variable buffer-display-time, always local in every buffer,
5449 holds the value of (current-time) as of the last time that a window
5450 was directed to display this buffer.
5451
5452 ** It is now meaningful to compare two window-configuration objects
5453 with `equal'. Two window-configuration objects are equal if they
5454 describe equivalent arrangements of windows, in the same frame--in
5455 other words, if they would give the same results if passed to
5456 set-window-configuration.
5457
5458 ** compare-window-configurations is a new function that compares two
5459 window configurations loosely. It ignores differences in saved buffer
5460 positions and scrolling, and considers only the structure and sizes of
5461 windows and the choice of buffers to display.
5462
5463 ** The variable minor-mode-overriding-map-alist allows major modes to
5464 override the key bindings of a minor mode. The elements of this alist
5465 look like the elements of minor-mode-map-alist: (VARIABLE . KEYMAP).
5466
5467 If the VARIABLE in an element of minor-mode-overriding-map-alist has a
5468 non-nil value, the paired KEYMAP is active, and totally overrides the
5469 map (if any) specified for the same variable in minor-mode-map-alist.
5470
5471 minor-mode-overriding-map-alist is automatically local in all buffers,
5472 and it is meant to be set by major modes.
5473
5474 ** The function match-string-no-properties is like match-string
5475 except that it discards all text properties from the result.
5476
5477 ** The function load-average now accepts an optional argument
5478 USE-FLOATS. If it is non-nil, the load average values are returned as
5479 floating point numbers, rather than as integers to be divided by 100.
5480
5481 ** The new variable temporary-file-directory specifies the directory
5482 to use for creating temporary files. The default value is determined
5483 in a reasonable way for your operating system; on GNU and Unix systems
5484 it is based on the TMP and TMPDIR environment variables.
5485
5486 ** Menu changes
5487
5488 *** easymenu.el now uses the new menu item format and supports the
5489 keywords :visible and :filter. The existing keyword :keys is now
5490 better supported.
5491
5492 The variable `easy-menu-precalculate-equivalent-keybindings' controls
5493 a new feature which calculates keyboard equivalents for the menu when
5494 you define the menu. The default is t. If you rarely use menus, you
5495 can set the variable to nil to disable this precalculation feature;
5496 then the calculation is done only if you use the menu bar.
5497
5498 *** A new format for menu items is supported.
5499
5500 In a keymap, a key binding that has the format
5501 (STRING . REAL-BINDING) or (STRING HELP-STRING . REAL-BINDING)
5502 defines a menu item. Now a menu item definition may also be a list that
5503 starts with the symbol `menu-item'.
5504
5505 The format is:
5506 (menu-item ITEM-NAME) or
5507 (menu-item ITEM-NAME REAL-BINDING . ITEM-PROPERTY-LIST)
5508 where ITEM-NAME is an expression which evaluates to the menu item
5509 string, and ITEM-PROPERTY-LIST has the form of a property list.
5510 The supported properties include
5511
5512 :enable FORM Evaluate FORM to determine whether the
5513 item is enabled.
5514 :visible FORM Evaluate FORM to determine whether the
5515 item should appear in the menu.
5516 :filter FILTER-FN
5517 FILTER-FN is a function of one argument,
5518 which will be REAL-BINDING.
5519 It should return a binding to use instead.
5520 :keys DESCRIPTION
5521 DESCRIPTION is a string that describes an equivalent keyboard
5522 binding for for REAL-BINDING. DESCRIPTION is expanded with
5523 `substitute-command-keys' before it is used.
5524 :key-sequence KEY-SEQUENCE
5525 KEY-SEQUENCE is a key-sequence for an equivalent
5526 keyboard binding.
5527 :key-sequence nil
5528 This means that the command normally has no
5529 keyboard equivalent.
5530 :help HELP HELP is the extra help string (not currently used).
5531 :button (TYPE . SELECTED)
5532 TYPE is :toggle or :radio.
5533 SELECTED is a form, to be evaluated, and its
5534 value says whether this button is currently selected.
5535
5536 Buttons are at the moment only simulated by prefixes in the menu.
5537 Eventually ordinary X-buttons may be supported.
5538
5539 (menu-item ITEM-NAME) defines unselectable item.
5540
5541 ** New event types
5542
5543 *** The new event type `mouse-wheel' is generated by a wheel on a
5544 mouse (such as the MS Intellimouse). The event contains a delta that
5545 corresponds to the amount and direction that the wheel is rotated,
5546 which is typically used to implement a scroll or zoom. The format is:
5547
5548 (mouse-wheel POSITION DELTA)
5549
5550 where POSITION is a list describing the position of the event in the
5551 same format as a mouse-click event, and DELTA is a signed number
5552 indicating the number of increments by which the wheel was rotated. A
5553 negative DELTA indicates that the wheel was rotated backwards, towards
5554 the user, and a positive DELTA indicates that the wheel was rotated
5555 forward, away from the user.
5556
5557 As of now, this event type is generated only on MS Windows.
5558
5559 *** The new event type `drag-n-drop' is generated when a group of
5560 files is selected in an application outside of Emacs, and then dragged
5561 and dropped onto an Emacs frame. The event contains a list of
5562 filenames that were dragged and dropped, which are then typically
5563 loaded into Emacs. The format is:
5564
5565 (drag-n-drop POSITION FILES)
5566
5567 where POSITION is a list describing the position of the event in the
5568 same format as a mouse-click event, and FILES is the list of filenames
5569 that were dragged and dropped.
5570
5571 As of now, this event type is generated only on MS Windows.
5572
5573 ** Changes relating to multibyte characters.
5574
5575 *** The variable enable-multibyte-characters is now read-only;
5576 any attempt to set it directly signals an error. The only way
5577 to change this value in an existing buffer is with set-buffer-multibyte.
5578
5579 *** In a string constant, `\ ' now stands for "nothing at all". You
5580 can use it to terminate a hex escape which is followed by a character
5581 that could otherwise be read as part of the hex escape.
5582
5583 *** String indices are now measured in characters, as they were
5584 in Emacs 19 and before.
5585
5586 The function chars-in-string has been deleted.
5587 The function concat-chars has been renamed to `string'.
5588
5589 *** The function set-buffer-multibyte sets the flag in the current
5590 buffer that says whether the buffer uses multibyte representation or
5591 unibyte representation. If the argument is nil, it selects unibyte
5592 representation. Otherwise it selects multibyte representation.
5593
5594 This function does not change the contents of the buffer, viewed
5595 as a sequence of bytes. However, it does change the contents
5596 viewed as characters; a sequence of two bytes which is treated as
5597 one character when the buffer uses multibyte representation
5598 will count as two characters using unibyte representation.
5599
5600 This function sets enable-multibyte-characters to record which
5601 representation is in use. It also adjusts various data in the buffer
5602 (including its markers, overlays and text properties) so that they are
5603 consistent with the new representation.
5604
5605 *** string-make-multibyte takes a string and converts it to multibyte
5606 representation. Most of the time, you don't need to care
5607 about the representation, because Emacs converts when necessary;
5608 however, it makes a difference when you compare strings.
5609
5610 The conversion of non-ASCII characters works by adding the value of
5611 nonascii-insert-offset to each character, or by translating them
5612 using the table nonascii-translation-table.
5613
5614 *** string-make-unibyte takes a string and converts it to unibyte
5615 representation. Most of the time, you don't need to care about the
5616 representation, but it makes a difference when you compare strings.
5617
5618 The conversion from multibyte to unibyte representation
5619 loses information; the only time Emacs performs it automatically
5620 is when inserting a multibyte string into a unibyte buffer.
5621
5622 *** string-as-multibyte takes a string, and returns another string
5623 which contains the same bytes, but treats them as multibyte.
5624
5625 *** string-as-unibyte takes a string, and returns another string
5626 which contains the same bytes, but treats them as unibyte.
5627
5628 *** The new function compare-strings lets you compare
5629 portions of two strings. Unibyte strings are converted to multibyte,
5630 so that a unibyte string can match a multibyte string.
5631 You can specify whether to ignore case or not.
5632
5633 *** assoc-ignore-case now uses compare-strings so that
5634 it can treat unibyte and multibyte strings as equal.
5635
5636 *** Regular expression operations and buffer string searches now
5637 convert the search pattern to multibyte or unibyte to accord with the
5638 buffer or string being searched.
5639
5640 One consequence is that you cannot always use \200-\377 inside of
5641 [...] to match all non-ASCII characters. This does still work when
5642 searching or matching a unibyte buffer or string, but not when
5643 searching or matching a multibyte string. Unfortunately, there is no
5644 obvious choice of syntax to use within [...] for that job. But, what
5645 you want is just to match all non-ASCII characters, the regular
5646 expression [^\0-\177] works for it.
5647
5648 *** Structure of coding system changed.
5649
5650 All coding systems (including aliases and subsidiaries) are named
5651 by symbols; the symbol's `coding-system' property is a vector
5652 which defines the coding system. Aliases share the same vector
5653 as the principal name, so that altering the contents of this
5654 vector affects the principal name and its aliases. You can define
5655 your own alias name of a coding system by the function
5656 define-coding-system-alias.
5657
5658 The coding system definition includes a property list of its own. Use
5659 the new functions `coding-system-get' and `coding-system-put' to
5660 access such coding system properties as post-read-conversion,
5661 pre-write-conversion, character-translation-table-for-decode,
5662 character-translation-table-for-encode, mime-charset, and
5663 safe-charsets. For instance, (coding-system-get 'iso-latin-1
5664 'mime-charset) gives the corresponding MIME-charset parameter
5665 `iso-8859-1'.
5666
5667 Among the coding system properties listed above, safe-charsets is new.
5668 The value of this property is a list of character sets which this
5669 coding system can correctly encode and decode. For instance:
5670 (coding-system-get 'iso-latin-1 'safe-charsets) => (ascii latin-iso8859-1)
5671
5672 Here, "correctly encode" means that the encoded character sets can
5673 also be handled safely by systems other than Emacs as far as they
5674 are capable of that coding system. Though, Emacs itself can encode
5675 the other character sets and read it back correctly.
5676
5677 *** The new function select-safe-coding-system can be used to find a
5678 proper coding system for encoding the specified region or string.
5679 This function requires a user interaction.
5680
5681 *** The new functions find-coding-systems-region and
5682 find-coding-systems-string are helper functions used by
5683 select-safe-coding-system. They return a list of all proper coding
5684 systems to encode a text in some region or string. If you don't want
5685 a user interaction, use one of these functions instead of
5686 select-safe-coding-system.
5687
5688 *** The explicit encoding and decoding functions, such as
5689 decode-coding-region and encode-coding-string, now set
5690 last-coding-system-used to reflect the actual way encoding or decoding
5691 was done.
5692
5693 *** The new function detect-coding-with-language-environment can be
5694 used to detect a coding system of text according to priorities of
5695 coding systems used by some specific language environment.
5696
5697 *** The functions detect-coding-region and detect-coding-string always
5698 return a list if the arg HIGHEST is nil. Thus, if only ASCII
5699 characters are found, they now return a list of single element
5700 `undecided' or its subsidiaries.
5701
5702 *** The new functions coding-system-change-eol-conversion and
5703 coding-system-change-text-conversion can be used to get a different
5704 coding system than what specified only in how end-of-line or text is
5705 converted.
5706
5707 *** The new function set-selection-coding-system can be used to set a
5708 coding system for communicating with other X clients.
5709
5710 *** The function `map-char-table' now passes as argument only valid
5711 character codes, plus generic characters that stand for entire
5712 character sets or entire subrows of a character set. In other words,
5713 each time `map-char-table' calls its FUNCTION argument, the key value
5714 either will be a valid individual character code, or will stand for a
5715 range of characters.
5716
5717 *** The new function `char-valid-p' can be used for checking whether a
5718 Lisp object is a valid character code or not.
5719
5720 *** The new function `charset-after' returns a charset of a character
5721 in the current buffer at position POS.
5722
5723 *** Input methods are now implemented using the variable
5724 input-method-function. If this is non-nil, its value should be a
5725 function; then, whenever Emacs reads an input event that is a printing
5726 character with no modifier bits, it calls that function, passing the
5727 event as an argument. Often this function will read more input, first
5728 binding input-method-function to nil.
5729
5730 The return value should be a list of the events resulting from input
5731 method processing. These events will be processed sequentially as
5732 input, before resorting to unread-command-events. Events returned by
5733 the input method function are not passed to the input method function,
5734 not even if they are printing characters with no modifier bits.
5735
5736 The input method function is not called when reading the second and
5737 subsequent events of a key sequence.
5738
5739 *** You can customize any language environment by using
5740 set-language-environment-hook and exit-language-environment-hook.
5741
5742 The hook `exit-language-environment-hook' should be used to undo
5743 customizations that you made with set-language-environment-hook. For
5744 instance, if you set up a special key binding for a specific language
5745 environment by set-language-environment-hook, you should set up
5746 exit-language-environment-hook to restore the normal key binding.
5747 \f
5748 * Changes in Emacs 20.1
5749
5750 ** Emacs has a new facility for customization of its many user
5751 options. It is called M-x customize. With this facility you can look
5752 at the many user options in an organized way; they are grouped into a
5753 tree structure.
5754
5755 M-x customize also knows what sorts of values are legitimate for each
5756 user option and ensures that you don't use invalid values.
5757
5758 With M-x customize, you can set options either for the present Emacs
5759 session or permanently. (Permanent settings are stored automatically
5760 in your .emacs file.)
5761
5762 ** Scroll bars are now on the left side of the window.
5763 You can change this with M-x customize-option scroll-bar-mode.
5764
5765 ** The mode line no longer includes the string `Emacs'.
5766 This makes more space in the mode line for other information.
5767
5768 ** When you select a region with the mouse, it is highlighted
5769 immediately afterward. At that time, if you type the DELETE key, it
5770 kills the region.
5771
5772 The BACKSPACE key, and the ASCII character DEL, do not do this; they
5773 delete the character before point, as usual.
5774
5775 ** In an incremental search the whole current match is highlighted
5776 on terminals which support this. (You can disable this feature
5777 by setting search-highlight to nil.)
5778
5779 ** In the minibuffer, in some cases, you can now use M-n to
5780 insert the default value into the minibuffer as text. In effect,
5781 the default value (if the minibuffer routines know it) is tacked
5782 onto the history "in the future". (The more normal use of the
5783 history list is to use M-p to insert minibuffer input used in the
5784 past.)
5785
5786 ** In Text mode, now only blank lines separate paragraphs.
5787 This makes it possible to get the full benefit of Adaptive Fill mode
5788 in Text mode, and other modes derived from it (such as Mail mode).
5789 TAB in Text mode now runs the command indent-relative; this
5790 makes a practical difference only when you use indented paragraphs.
5791
5792 As a result, the old Indented Text mode is now identical to Text mode,
5793 and is an alias for it.
5794
5795 If you want spaces at the beginning of a line to start a paragraph,
5796 use the new mode, Paragraph Indent Text mode.
5797
5798 ** Scrolling changes
5799
5800 *** Scroll commands to scroll a whole screen now preserve the screen
5801 position of the cursor, if scroll-preserve-screen-position is non-nil.
5802
5803 In this mode, if you scroll several screens back and forth, finishing
5804 on the same screen where you started, the cursor goes back to the line
5805 where it started.
5806
5807 *** If you set scroll-conservatively to a small number, then when you
5808 move point a short distance off the screen, Emacs will scroll the
5809 screen just far enough to bring point back on screen, provided that
5810 does not exceed `scroll-conservatively' lines.
5811
5812 *** The new variable scroll-margin says how close point can come to the
5813 top or bottom of a window. It is a number of screen lines; if point
5814 comes within that many lines of the top or bottom of the window, Emacs
5815 recenters the window.
5816
5817 ** International character set support (MULE)
5818
5819 Emacs now supports a wide variety of international character sets,
5820 including European variants of the Latin alphabet, as well as Chinese,
5821 Devanagari (Hindi and Marathi), Ethiopian, Greek, IPA, Japanese,
5822 Korean, Lao, Russian, Thai, Tibetan, and Vietnamese scripts. These
5823 features have been merged from the modified version of Emacs known as
5824 MULE (for "MULti-lingual Enhancement to GNU Emacs")
5825
5826 Users of these scripts have established many more-or-less standard
5827 coding systems for storing files. Emacs uses a single multibyte
5828 character encoding within Emacs buffers; it can translate from a wide
5829 variety of coding systems when reading a file and can translate back
5830 into any of these coding systems when saving a file.
5831
5832 Keyboards, even in the countries where these character sets are used,
5833 generally don't have keys for all the characters in them. So Emacs
5834 supports various "input methods", typically one for each script or
5835 language, to make it possible to type them.
5836
5837 The Emacs internal multibyte encoding represents a non-ASCII
5838 character as a sequence of bytes in the range 0200 through 0377.
5839
5840 The new prefix key C-x RET is used for commands that pertain
5841 to multibyte characters, coding systems, and input methods.
5842
5843 You can disable multibyte character support as follows:
5844
5845 (setq-default enable-multibyte-characters nil)
5846
5847 Calling the function standard-display-european turns off multibyte
5848 characters, unless you specify a non-nil value for the second
5849 argument, AUTO. This provides compatibility for people who are
5850 already using standard-display-european to continue using unibyte
5851 characters for their work until they want to change.
5852
5853 *** Input methods
5854
5855 An input method is a kind of character conversion which is designed
5856 specifically for interactive input. In Emacs, typically each language
5857 has its own input method (though sometimes several languages which use
5858 the same characters can share one input method). Some languages
5859 support several input methods.
5860
5861 The simplest kind of input method works by mapping ASCII letters into
5862 another alphabet. This is how the Greek and Russian input methods
5863 work.
5864
5865 A more powerful technique is composition: converting sequences of
5866 characters into one letter. Many European input methods use
5867 composition to produce a single non-ASCII letter from a sequence which
5868 consists of a letter followed by diacritics. For example, a' is one
5869 sequence of two characters that might be converted into a single
5870 letter.
5871
5872 The input methods for syllabic scripts typically use mapping followed
5873 by conversion. The input methods for Thai and Korean work this way.
5874 First, letters are mapped into symbols for particular sounds or tone
5875 marks; then, sequences of these which make up a whole syllable are
5876 mapped into one syllable sign--most often a "composite character".
5877
5878 None of these methods works very well for Chinese and Japanese, so
5879 they are handled specially. First you input a whole word using
5880 phonetic spelling; then, after the word is in the buffer, Emacs
5881 converts it into one or more characters using a large dictionary.
5882
5883 Since there is more than one way to represent a phonetically spelled
5884 word using Chinese characters, Emacs can only guess which one to use;
5885 typically these input methods give you a way to say "guess again" if
5886 the first guess is wrong.
5887
5888 *** The command C-x RET m (toggle-enable-multibyte-characters)
5889 turns multibyte character support on or off for the current buffer.
5890
5891 If multibyte character support is turned off in a buffer, then each
5892 byte is a single character, even codes 0200 through 0377--exactly as
5893 they did in Emacs 19.34. This includes the features for support for
5894 the European characters, ISO Latin-1 and ISO Latin-2.
5895
5896 However, there is no need to turn off multibyte character support to
5897 use ISO Latin-1 or ISO Latin-2; the Emacs multibyte character set
5898 includes all the characters in these character sets, and Emacs can
5899 translate automatically to and from either one.
5900
5901 *** Visiting a file in unibyte mode.
5902
5903 Turning off multibyte character support in the buffer after visiting a
5904 file with multibyte code conversion will display the multibyte
5905 sequences already in the buffer, byte by byte. This is probably not
5906 what you want.
5907
5908 If you want to edit a file of unibyte characters (Latin-1, for
5909 example), you can do it by specifying `no-conversion' as the coding
5910 system when reading the file. This coding system also turns off
5911 multibyte characters in that buffer.
5912
5913 If you turn off multibyte character support entirely, this turns off
5914 character conversion as well.
5915
5916 *** Displaying international characters on X Windows.
5917
5918 A font for X typically displays just one alphabet or script.
5919 Therefore, displaying the entire range of characters Emacs supports
5920 requires using many fonts.
5921
5922 Therefore, Emacs now supports "fontsets". Each fontset is a
5923 collection of fonts, each assigned to a range of character codes.
5924
5925 A fontset has a name, like a font. Individual fonts are defined by
5926 the X server; fontsets are defined within Emacs itself. But once you
5927 have defined a fontset, you can use it in a face or a frame just as
5928 you would use a font.
5929
5930 If a fontset specifies no font for a certain character, or if it
5931 specifies a font that does not exist on your system, then it cannot
5932 display that character. It will display an empty box instead.
5933
5934 The fontset height and width are determined by the ASCII characters
5935 (that is, by the font in the fontset which is used for ASCII
5936 characters). If another font in the fontset has a different height,
5937 or the wrong width, then characters assigned to that font are clipped,
5938 and displayed within a box if highlight-wrong-size-font is non-nil.
5939
5940 *** Defining fontsets.
5941
5942 Emacs does not use any fontset by default. Its default font is still
5943 chosen as in previous versions. You can tell Emacs to use a fontset
5944 with the `-fn' option or the `Font' X resource.
5945
5946 Emacs creates a standard fontset automatically according to the value
5947 of standard-fontset-spec. This fontset's short name is
5948 `fontset-standard'. Bold, italic, and bold-italic variants of the
5949 standard fontset are created automatically.
5950
5951 If you specify a default ASCII font with the `Font' resource or `-fn'
5952 argument, a fontset is generated from it. This works by replacing the
5953 FOUNDARY, FAMILY, ADD_STYLE, and AVERAGE_WIDTH fields of the font name
5954 with `*' then using this to specify a fontset. This fontset's short
5955 name is `fontset-startup'.
5956
5957 Emacs checks resources of the form Fontset-N where N is 0, 1, 2...
5958 The resource value should have this form:
5959 FONTSET-NAME, [CHARSET-NAME:FONT-NAME]...
5960 FONTSET-NAME should have the form of a standard X font name, except:
5961 * most fields should be just the wild card "*".
5962 * the CHARSET_REGISTRY field should be "fontset"
5963 * the CHARSET_ENCODING field can be any nickname of the fontset.
5964 The construct CHARSET-NAME:FONT-NAME can be repeated any number
5965 of times; each time specifies the font for one character set.
5966 CHARSET-NAME should be the name name of a character set, and
5967 FONT-NAME should specify an actual font to use for that character set.
5968
5969 Each of these fontsets has an alias which is made from the
5970 last two font name fields, CHARSET_REGISTRY and CHARSET_ENCODING.
5971 You can refer to the fontset by that alias or by its full name.
5972
5973 For any character sets that you don't mention, Emacs tries to choose a
5974 font by substituting into FONTSET-NAME. For instance, with the
5975 following resource,
5976 Emacs*Fontset-0: -*-fixed-medium-r-normal-*-24-*-*-*-*-*-fontset-24
5977 the font for ASCII is generated as below:
5978 -*-fixed-medium-r-normal-*-24-*-ISO8859-1
5979 Here is the substitution rule:
5980 Change CHARSET_REGISTRY and CHARSET_ENCODING to that of the charset
5981 defined in the variable x-charset-registries. For instance, ASCII has
5982 the entry (ascii . "ISO8859-1") in this variable. Then, reduce
5983 sequences of wild cards -*-...-*- with a single wildcard -*-.
5984 (This is to prevent use of auto-scaled fonts.)
5985
5986 The function which processes the fontset resource value to create the
5987 fontset is called create-fontset-from-fontset-spec. You can also call
5988 that function explicitly to create a fontset.
5989
5990 With the X resource Emacs.Font, you can specify a fontset name just
5991 like an actual font name. But be careful not to specify a fontset
5992 name in a wildcard resource like Emacs*Font--that tries to specify the
5993 fontset for other purposes including menus, and they cannot handle
5994 fontsets.
5995
5996 *** The command M-x set-language-environment sets certain global Emacs
5997 defaults for a particular choice of language.
5998
5999 Selecting a language environment typically specifies a default input
6000 method and which coding systems to recognize automatically when
6001 visiting files. However, it does not try to reread files you have
6002 already visited; the text in those buffers is not affected. The
6003 language environment may also specify a default choice of coding
6004 system for new files that you create.
6005
6006 It makes no difference which buffer is current when you use
6007 set-language-environment, because these defaults apply globally to the
6008 whole Emacs session.
6009
6010 For example, M-x set-language-environment RET Latin-1 RET
6011 chooses the Latin-1 character set. In the .emacs file, you can do this
6012 with (set-language-environment "Latin-1").
6013
6014 *** The command C-x RET f (set-buffer-file-coding-system)
6015 specifies the file coding system for the current buffer. This
6016 specifies what sort of character code translation to do when saving
6017 the file. As an argument, you must specify the name of one of the
6018 coding systems that Emacs supports.
6019
6020 *** The command C-x RET c (universal-coding-system-argument)
6021 lets you specify a coding system when you read or write a file.
6022 This command uses the minibuffer to read a coding system name.
6023 After you exit the minibuffer, the specified coding system
6024 is used for *the immediately following command*.
6025
6026 So if the immediately following command is a command to read or
6027 write a file, it uses the specified coding system for that file.
6028
6029 If the immediately following command does not use the coding system,
6030 then C-x RET c ultimately has no effect.
6031
6032 For example, C-x RET c iso-8859-1 RET C-x C-f temp RET
6033 visits the file `temp' treating it as ISO Latin-1.
6034
6035 *** You can specify the coding system for a file using the -*-
6036 construct. Include `coding: CODINGSYSTEM;' inside the -*-...-*-
6037 to specify use of coding system CODINGSYSTEM. You can also
6038 specify the coding system in a local variable list at the end
6039 of the file.
6040
6041 *** The command C-x RET t (set-terminal-coding-system) specifies
6042 the coding system for terminal output. If you specify a character
6043 code for terminal output, all characters output to the terminal are
6044 translated into that character code.
6045
6046 This feature is useful for certain character-only terminals built in
6047 various countries to support the languages of those countries.
6048
6049 By default, output to the terminal is not translated at all.
6050
6051 *** The command C-x RET k (set-keyboard-coding-system) specifies
6052 the coding system for keyboard input.
6053
6054 Character code translation of keyboard input is useful for terminals
6055 with keys that send non-ASCII graphic characters--for example,
6056 some terminals designed for ISO Latin-1 or subsets of it.
6057
6058 By default, keyboard input is not translated at all.
6059
6060 Character code translation of keyboard input is similar to using an
6061 input method, in that both define sequences of keyboard input that
6062 translate into single characters. However, input methods are designed
6063 to be convenient for interactive use, while the code translations are
6064 designed to work with terminals.
6065
6066 *** The command C-x RET p (set-buffer-process-coding-system)
6067 specifies the coding system for input and output to a subprocess.
6068 This command applies to the current buffer; normally, each subprocess
6069 has its own buffer, and thus you can use this command to specify
6070 translation to and from a particular subprocess by giving the command
6071 in the corresponding buffer.
6072
6073 By default, process input and output are not translated at all.
6074
6075 *** The variable file-name-coding-system specifies the coding system
6076 to use for encoding file names before operating on them.
6077 It is also used for decoding file names obtained from the system.
6078
6079 *** The command C-\ (toggle-input-method) activates or deactivates
6080 an input method. If no input method has been selected before, the
6081 command prompts for you to specify the language and input method you
6082 want to use.
6083
6084 C-u C-\ (select-input-method) lets you switch to a different input
6085 method. C-h C-\ (or C-h I) describes the current input method.
6086
6087 *** Some input methods remap the keyboard to emulate various keyboard
6088 layouts commonly used for particular scripts. How to do this
6089 remapping properly depends on your actual keyboard layout. To specify
6090 which layout your keyboard has, use M-x quail-set-keyboard-layout.
6091
6092 *** The command C-h C (describe-coding-system) displays
6093 the coding systems currently selected for various purposes, plus
6094 related information.
6095
6096 *** The command C-h h (view-hello-file) displays a file called
6097 HELLO, which has examples of text in many languages, using various
6098 scripts.
6099
6100 *** The command C-h L (describe-language-support) displays
6101 information about the support for a particular language.
6102 You specify the language as an argument.
6103
6104 *** The mode line now contains a letter or character that identifies
6105 the coding system used in the visited file. It normally follows the
6106 first dash.
6107
6108 A dash indicates the default state of affairs: no code conversion
6109 (except CRLF => newline if appropriate). `=' means no conversion
6110 whatsoever. The ISO 8859 coding systems are represented by digits
6111 1 through 9. Other coding systems are represented by letters:
6112
6113 A alternativnyj (Russian)
6114 B big5 (Chinese)
6115 C cn-gb-2312 (Chinese)
6116 C iso-2022-cn (Chinese)
6117 D in-is13194-devanagari (Indian languages)
6118 E euc-japan (Japanese)
6119 I iso-2022-cjk or iso-2022-ss2 (Chinese, Japanese, Korean)
6120 J junet (iso-2022-7) or old-jis (iso-2022-jp-1978-irv) (Japanese)
6121 K euc-korea (Korean)
6122 R koi8 (Russian)
6123 Q tibetan
6124 S shift_jis (Japanese)
6125 T lao
6126 T tis620 (Thai)
6127 V viscii or vscii (Vietnamese)
6128 i iso-2022-lock (Chinese, Japanese, Korean)
6129 k iso-2022-kr (Korean)
6130 v viqr (Vietnamese)
6131 z hz (Chinese)
6132
6133 When you are using a character-only terminal (not a window system),
6134 two additional characters appear in between the dash and the file
6135 coding system. These two characters describe the coding system for
6136 keyboard input, and the coding system for terminal output.
6137
6138 *** The new variable rmail-file-coding-system specifies the code
6139 conversion to use for RMAIL files. The default value is nil.
6140
6141 When you read mail with Rmail, each message is decoded automatically
6142 into Emacs' internal format. This has nothing to do with
6143 rmail-file-coding-system. That variable controls reading and writing
6144 Rmail files themselves.
6145
6146 *** The new variable sendmail-coding-system specifies the code
6147 conversion for outgoing mail. The default value is nil.
6148
6149 Actually, there are three different ways of specifying the coding system
6150 for sending mail:
6151
6152 - If you use C-x RET f in the mail buffer, that takes priority.
6153 - Otherwise, if you set sendmail-coding-system non-nil, that specifies it.
6154 - Otherwise, the default coding system for new files is used,
6155 if that is non-nil. That comes from your language environment.
6156 - Otherwise, Latin-1 is used.
6157
6158 *** The command C-h t (help-with-tutorial) accepts a prefix argument
6159 to specify the language for the tutorial file. Currently, English,
6160 Japanese, Korean and Thai are supported. We welcome additional
6161 translations.
6162
6163 ** An easy new way to visit a file with no code or format conversion
6164 of any kind: Use M-x find-file-literally. There is also a command
6165 insert-file-literally which inserts a file into the current buffer
6166 without any conversion.
6167
6168 ** C-q's handling of octal character codes is changed.
6169 You can now specify any number of octal digits.
6170 RET terminates the digits and is discarded;
6171 any other non-digit terminates the digits and is then used as input.
6172
6173 ** There are new commands for looking up Info documentation for
6174 functions, variables and file names used in your programs.
6175
6176 Type M-x info-lookup-symbol to look up a symbol in the buffer at point.
6177 Type M-x info-lookup-file to look up a file in the buffer at point.
6178
6179 Precisely which Info files are used to look it up depends on the major
6180 mode. For example, in C mode, the GNU libc manual is used.
6181
6182 ** M-TAB in most programming language modes now runs the command
6183 complete-symbol. This command performs completion on the symbol name
6184 in the buffer before point.
6185
6186 With a numeric argument, it performs completion based on the set of
6187 symbols documented in the Info files for the programming language that
6188 you are using.
6189
6190 With no argument, it does completion based on the current tags tables,
6191 just like the old binding of M-TAB (complete-tag).
6192
6193 ** File locking works with NFS now.
6194
6195 The lock file for FILENAME is now a symbolic link named .#FILENAME,
6196 in the same directory as FILENAME.
6197
6198 This means that collision detection between two different machines now
6199 works reasonably well; it also means that no file server or directory
6200 can become a bottleneck.
6201
6202 The new method does have drawbacks. It means that collision detection
6203 does not operate when you edit a file in a directory where you cannot
6204 create new files. Collision detection also doesn't operate when the
6205 file server does not support symbolic links. But these conditions are
6206 rare, and the ability to have collision detection while using NFS is
6207 so useful that the change is worth while.
6208
6209 When Emacs or a system crashes, this may leave behind lock files which
6210 are stale. So you may occasionally get warnings about spurious
6211 collisions. When you determine that the collision is spurious, just
6212 tell Emacs to go ahead anyway.
6213
6214 ** If you wish to use Show Paren mode to display matching parentheses,
6215 it is no longer sufficient to load paren.el. Instead you must call
6216 show-paren-mode.
6217
6218 ** If you wish to use Delete Selection mode to replace a highlighted
6219 selection when you insert new text, it is no longer sufficient to load
6220 delsel.el. Instead you must call the function delete-selection-mode.
6221
6222 ** If you wish to use Partial Completion mode to complete partial words
6223 within symbols or filenames, it is no longer sufficient to load
6224 complete.el. Instead you must call the function partial-completion-mode.
6225
6226 ** If you wish to use uniquify to rename buffers for you,
6227 it is no longer sufficient to load uniquify.el. You must also
6228 set uniquify-buffer-name-style to one of the non-nil legitimate values.
6229
6230 ** Changes in View mode.
6231
6232 *** Several new commands are available in View mode.
6233 Do H in view mode for a list of commands.
6234
6235 *** There are two new commands for entering View mode:
6236 view-file-other-frame and view-buffer-other-frame.
6237
6238 *** Exiting View mode does a better job of restoring windows to their
6239 previous state.
6240
6241 *** New customization variable view-scroll-auto-exit. If non-nil,
6242 scrolling past end of buffer makes view mode exit.
6243
6244 *** New customization variable view-exits-all-viewing-windows. If
6245 non-nil, view-mode will at exit restore all windows viewing buffer,
6246 not just the selected window.
6247
6248 *** New customization variable view-read-only. If non-nil, visiting a
6249 read-only file automatically enters View mode, and toggle-read-only
6250 turns View mode on or off.
6251
6252 *** New customization variable view-remove-frame-by-deleting controls
6253 how to remove a not needed frame at view mode exit. If non-nil,
6254 delete the frame, if nil make an icon of it.
6255
6256 ** C-x v l, the command to print a file's version control log,
6257 now positions point at the entry for the file's current branch version.
6258
6259 ** C-x v =, the command to compare a file with the last checked-in version,
6260 has a new feature. If the file is currently not locked, so that it is
6261 presumably identical to the last checked-in version, the command now asks
6262 which version to compare with.
6263
6264 ** When using hideshow.el, incremental search can temporarily show hidden
6265 blocks if a match is inside the block.
6266
6267 The block is hidden again if the search is continued and the next match
6268 is outside the block. By customizing the variable
6269 isearch-hide-immediately you can choose to hide all the temporarily
6270 shown blocks only when exiting from incremental search.
6271
6272 By customizing the variable hs-isearch-open you can choose what kind
6273 of blocks to temporarily show during isearch: comment blocks, code
6274 blocks, all of them or none.
6275
6276 ** The new command C-x 4 0 (kill-buffer-and-window) kills the
6277 current buffer and deletes the selected window. It asks for
6278 confirmation first.
6279
6280 ** C-x C-w, which saves the buffer into a specified file name,
6281 now changes the major mode according to that file name.
6282 However, the mode will not be changed if
6283 (1) a local variables list or the `-*-' line specifies a major mode, or
6284 (2) the current major mode is a "special" mode,
6285 not suitable for ordinary files, or
6286 (3) the new file name does not particularly specify any mode.
6287
6288 This applies to M-x set-visited-file-name as well.
6289
6290 However, if you set change-major-mode-with-file-name to nil, then
6291 these commands do not change the major mode.
6292
6293 ** M-x occur changes.
6294
6295 *** If the argument to M-x occur contains upper case letters,
6296 it performs a case-sensitive search.
6297
6298 *** In the *Occur* buffer made by M-x occur,
6299 if you type g or M-x revert-buffer, this repeats the search
6300 using the same regular expression and the same buffer as before.
6301
6302 ** In Transient Mark mode, the region in any one buffer is highlighted
6303 in just one window at a time. At first, it is highlighted in the
6304 window where you set the mark. The buffer's highlighting remains in
6305 that window unless you select to another window which shows the same
6306 buffer--then the highlighting moves to that window.
6307
6308 ** The feature to suggest key bindings when you use M-x now operates
6309 after the command finishes. The message suggesting key bindings
6310 appears temporarily in the echo area. The previous echo area contents
6311 come back after a few seconds, in case they contain useful information.
6312
6313 ** Each frame now independently records the order for recently
6314 selected buffers, so that the default for C-x b is now based on the
6315 buffers recently selected in the selected frame.
6316
6317 ** Outline mode changes.
6318
6319 *** Outline mode now uses overlays (this is the former noutline.el).
6320
6321 *** Incremental searches skip over invisible text in Outline mode.
6322
6323 ** When a minibuffer window is active but not the selected window, if
6324 you try to use the minibuffer, you used to get a nested minibuffer.
6325 Now, this not only gives an error, it also cancels the minibuffer that
6326 was already active.
6327
6328 The motive for this change is so that beginning users do not
6329 unknowingly move away from minibuffers, leaving them active, and then
6330 get confused by it.
6331
6332 If you want to be able to have recursive minibuffers, you must
6333 set enable-recursive-minibuffers to non-nil.
6334
6335 ** Changes in dynamic abbrevs.
6336
6337 *** Expanding dynamic abbrevs with M-/ is now smarter about case
6338 conversion. If the expansion has mixed case not counting the first
6339 character, and the abbreviation matches the beginning of the expansion
6340 including case, then the expansion is copied verbatim.
6341
6342 The expansion is also copied verbatim if the abbreviation itself has
6343 mixed case. And using SPC M-/ to copy an additional word always
6344 copies it verbatim except when the previous copied word is all caps.
6345
6346 *** The values of `dabbrev-case-replace' and `dabbrev-case-fold-search'
6347 are no longer Lisp expressions. They have simply three possible
6348 values.
6349
6350 `dabbrev-case-replace' has these three values: nil (don't preserve
6351 case), t (do), or `case-replace' (do like M-x query-replace).
6352 `dabbrev-case-fold-search' has these three values: nil (don't ignore
6353 case), t (do), or `case-fold-search' (do like search).
6354
6355 ** Minibuffer history lists are truncated automatically now to a
6356 certain length. The variable history-length specifies how long they
6357 can be. The default value is 30.
6358
6359 ** Changes in Mail mode.
6360
6361 *** The key C-x m no longer runs the `mail' command directly.
6362 Instead, it runs the command `compose-mail', which invokes the mail
6363 composition mechanism you have selected with the variable
6364 `mail-user-agent'. The default choice of user agent is
6365 `sendmail-user-agent', which gives behavior compatible with the old
6366 behavior.
6367
6368 C-x 4 m now runs compose-mail-other-window, and C-x 5 m runs
6369 compose-mail-other-frame.
6370
6371 *** While composing a reply to a mail message, from Rmail, you can use
6372 the command C-c C-r to cite just the region from the message you are
6373 replying to. This copies the text which is the selected region in the
6374 buffer that shows the original message.
6375
6376 *** The command C-c C-i inserts a file at the end of the message,
6377 with separator lines around the contents.
6378
6379 *** The command M-x expand-mail-aliases expands all mail aliases
6380 in suitable mail headers. Emacs automatically extracts mail alias
6381 definitions from your mail alias file (e.g., ~/.mailrc). You do not
6382 need to expand mail aliases yourself before sending mail.
6383
6384 *** New features in the mail-complete command.
6385
6386 **** The mail-complete command now inserts the user's full name,
6387 for local users or if that is known. The variable mail-complete-style
6388 controls the style to use, and whether to do this at all.
6389 Its values are like those of mail-from-style.
6390
6391 **** The variable mail-passwd-command lets you specify a shell command
6392 to run to fetch a set of password-entries that add to the ones in
6393 /etc/passwd.
6394
6395 **** The variable mail-passwd-file now specifies a list of files to read
6396 to get the list of user ids. By default, one file is used:
6397 /etc/passwd.
6398
6399 ** You can "quote" a file name to inhibit special significance of
6400 special syntax, by adding `/:' to the beginning. Thus, if you have a
6401 directory named `/foo:', you can prevent it from being treated as a
6402 reference to a remote host named `foo' by writing it as `/:/foo:'.
6403
6404 Emacs uses this new construct automatically when necessary, such as
6405 when you start it with a working directory whose name might otherwise
6406 be taken to be magic.
6407
6408 ** There is a new command M-x grep-find which uses find to select
6409 files to search through, and grep to scan them. The output is
6410 available in a Compile mode buffer, as with M-x grep.
6411
6412 M-x grep now uses the -e option if the grep program supports that.
6413 (-e prevents problems if the search pattern starts with a dash.)
6414
6415 ** In Dired, the & command now flags for deletion the files whose names
6416 suggest they are probably not needed in the long run.
6417
6418 In Dired, * is now a prefix key for mark-related commands.
6419
6420 new key dired.el binding old key
6421 ------- ---------------- -------
6422 * c dired-change-marks c
6423 * m dired-mark m
6424 * * dired-mark-executables * (binding deleted)
6425 * / dired-mark-directories / (binding deleted)
6426 * @ dired-mark-symlinks @ (binding deleted)
6427 * u dired-unmark u
6428 * DEL dired-unmark-backward DEL
6429 * ? dired-unmark-all-files M-C-?
6430 * ! dired-unmark-all-marks
6431 * % dired-mark-files-regexp % m
6432 * C-n dired-next-marked-file M-}
6433 * C-p dired-prev-marked-file M-{
6434
6435 ** Rmail changes.
6436
6437 *** When Rmail cannot convert your incoming mail into Babyl format, it
6438 saves the new mail in the file RMAILOSE.n, where n is an integer
6439 chosen to make a unique name. This way, Rmail will not keep crashing
6440 each time you run it.
6441
6442 *** In Rmail, the variable rmail-summary-line-count-flag now controls
6443 whether to include the line count in the summary. Non-nil means yes.
6444
6445 *** In Rmail summary buffers, d and C-d (the commands to delete
6446 messages) now take repeat counts as arguments. A negative argument
6447 means to move in the opposite direction.
6448
6449 *** In Rmail, the t command now takes an optional argument which lets
6450 you specify whether to show the message headers in full or pruned.
6451
6452 *** In Rmail, the new command w (rmail-output-body-to-file) writes
6453 just the body of the current message into a file, without the headers.
6454 It takes the file name from the message subject, by default, but you
6455 can edit that file name in the minibuffer before it is actually used
6456 for output.
6457
6458 ** Gnus changes.
6459
6460 *** nntp.el has been totally rewritten in an asynchronous fashion.
6461
6462 *** Article prefetching functionality has been moved up into
6463 Gnus.
6464
6465 *** Scoring can now be performed with logical operators like
6466 `and', `or', `not', and parent redirection.
6467
6468 *** Article washing status can be displayed in the
6469 article mode line.
6470
6471 *** gnus.el has been split into many smaller files.
6472
6473 *** Suppression of duplicate articles based on Message-ID.
6474
6475 (setq gnus-suppress-duplicates t)
6476
6477 *** New variables for specifying what score and adapt files
6478 are to be considered home score and adapt files. See
6479 `gnus-home-score-file' and `gnus-home-adapt-files'.
6480
6481 *** Groups can inherit group parameters from parent topics.
6482
6483 *** Article editing has been revamped and is now usable.
6484
6485 *** Signatures can be recognized in more intelligent fashions.
6486 See `gnus-signature-separator' and `gnus-signature-limit'.
6487
6488 *** Summary pick mode has been made to look more nn-like.
6489 Line numbers are displayed and the `.' command can be
6490 used to pick articles.
6491
6492 *** Commands for moving the .newsrc.eld from one server to
6493 another have been added.
6494
6495 `M-x gnus-change-server'
6496
6497 *** A way to specify that "uninteresting" fields be suppressed when
6498 generating lines in buffers.
6499
6500 *** Several commands in the group buffer can be undone with
6501 `M-C-_'.
6502
6503 *** Scoring can be done on words using the new score type `w'.
6504
6505 *** Adaptive scoring can be done on a Subject word-by-word basis:
6506
6507 (setq gnus-use-adaptive-scoring '(word))
6508
6509 *** Scores can be decayed.
6510
6511 (setq gnus-decay-scores t)
6512
6513 *** Scoring can be performed using a regexp on the Date header. The
6514 Date is normalized to compact ISO 8601 format first.
6515
6516 *** A new command has been added to remove all data on articles from
6517 the native server.
6518
6519 `M-x gnus-group-clear-data-on-native-groups'
6520
6521 *** A new command for reading collections of documents
6522 (nndoc with nnvirtual on top) has been added -- `M-C-d'.
6523
6524 *** Process mark sets can be pushed and popped.
6525
6526 *** A new mail-to-news backend makes it possible to post
6527 even when the NNTP server doesn't allow posting.
6528
6529 *** A new backend for reading searches from Web search engines
6530 (DejaNews, Alta Vista, InReference) has been added.
6531
6532 Use the `G w' command in the group buffer to create such
6533 a group.
6534
6535 *** Groups inside topics can now be sorted using the standard
6536 sorting functions, and each topic can be sorted independently.
6537
6538 See the commands under the `T S' submap.
6539
6540 *** Subsets of the groups can be sorted independently.
6541
6542 See the commands under the `G P' submap.
6543
6544 *** Cached articles can be pulled into the groups.
6545
6546 Use the `Y c' command.
6547
6548 *** Score files are now applied in a more reliable order.
6549
6550 *** Reports on where mail messages end up can be generated.
6551
6552 `M-x nnmail-split-history'
6553
6554 *** More hooks and functions have been added to remove junk
6555 from incoming mail before saving the mail.
6556
6557 See `nnmail-prepare-incoming-header-hook'.
6558
6559 *** The nnml mail backend now understands compressed article files.
6560
6561 *** To enable Gnus to read/post multi-lingual articles, you must execute
6562 the following code, for instance, in your .emacs.
6563
6564 (add-hook 'gnus-startup-hook 'gnus-mule-initialize)
6565
6566 Then, when you start Gnus, it will decode non-ASCII text automatically
6567 and show appropriate characters. (Note: if you are using gnus-mime
6568 from the SEMI package, formerly known as TM, you should NOT add this
6569 hook to gnus-startup-hook; gnus-mime has its own method of handling
6570 this issue.)
6571
6572 Since it is impossible to distinguish all coding systems
6573 automatically, you may need to specify a choice of coding system for a
6574 particular news group. This can be done by:
6575
6576 (gnus-mule-add-group NEWSGROUP 'CODING-SYSTEM)
6577
6578 Here NEWSGROUP should be a string which names a newsgroup or a tree
6579 of newsgroups. If NEWSGROUP is "XXX.YYY", all news groups under
6580 "XXX.YYY" (including "XXX.YYY.ZZZ") will use the specified coding
6581 system. CODING-SYSTEM specifies which coding system to use (for both
6582 for reading and posting).
6583
6584 CODING-SYSTEM can also be a cons cell of the form
6585 (READ-CODING-SYSTEM . POST-CODING-SYSTEM)
6586 Then READ-CODING-SYSTEM is used when you read messages from the
6587 newsgroups, while POST-CODING-SYSTEM is used when you post messages
6588 there.
6589
6590 Emacs knows the right coding systems for certain newsgroups by
6591 default. Here are some of these default settings:
6592
6593 (gnus-mule-add-group "fj" 'iso-2022-7)
6594 (gnus-mule-add-group "alt.chinese.text" 'hz-gb-2312)
6595 (gnus-mule-add-group "alt.hk" 'hz-gb-2312)
6596 (gnus-mule-add-group "alt.chinese.text.big5" 'cn-big5)
6597 (gnus-mule-add-group "soc.culture.vietnamese" '(nil . viqr))
6598
6599 When you reply by mail to an article, these settings are ignored;
6600 the mail is encoded according to sendmail-coding-system, as usual.
6601
6602 ** CC mode changes.
6603
6604 *** If you edit primarily one style of C (or C++, Objective-C, Java)
6605 code, you may want to make the CC Mode style variables have global
6606 values so that you can set them directly in your .emacs file. To do
6607 this, set c-style-variables-are-local-p to nil in your .emacs file.
6608 Note that this only takes effect if you do it *before* cc-mode.el is
6609 loaded.
6610
6611 If you typically edit more than one style of C (or C++, Objective-C,
6612 Java) code in a single Emacs session, you may want to make the CC Mode
6613 style variables have buffer local values. By default, all buffers
6614 share the same style variable settings; to make them buffer local, set
6615 c-style-variables-are-local-p to t in your .emacs file. Note that you
6616 must do this *before* CC Mode is loaded.
6617
6618 *** The new variable c-indentation-style holds the C style name
6619 of the current buffer.
6620
6621 *** The variable c-block-comments-indent-p has been deleted, because
6622 it is no longer necessary. C mode now handles all the supported styles
6623 of block comments, with no need to say which one you will use.
6624
6625 *** There is a new indentation style "python", which specifies the C
6626 style that the Python developers like.
6627
6628 *** There is a new c-cleanup-list option: brace-elseif-brace.
6629 This says to put ...} else if (...) {... on one line,
6630 just as brace-else-brace says to put ...} else {... on one line.
6631
6632 ** VC Changes [new]
6633
6634 ** In vc-retrieve-snapshot (C-x v r), if you don't specify a snapshot
6635 name, it retrieves the *latest* versions of all files in the current
6636 directory and its subdirectories (aside from files already locked).
6637
6638 This feature is useful if your RCS directory is a link to a common
6639 master directory, and you want to pick up changes made by other
6640 developers.
6641
6642 You can do the same thing for an individual file by typing C-u C-x C-q
6643 RET in a buffer visiting that file.
6644
6645 *** VC can now handle files under CVS that are being "watched" by
6646 other developers. Such files are made read-only by CVS. To get a
6647 writable copy, type C-x C-q in a buffer visiting such a file. VC then
6648 calls "cvs edit", which notifies the other developers of it.
6649
6650 *** vc-version-diff (C-u C-x v =) now suggests reasonable defaults for
6651 version numbers, based on the current state of the file.
6652
6653 ** Calendar changes.
6654
6655 A new function, list-holidays, allows you list holidays or subclasses
6656 of holidays for ranges of years. Related menu items allow you do this
6657 for the year of the selected date, or the following/previous years.
6658
6659 ** ps-print changes
6660
6661 There are some new user variables for customizing the page layout.
6662
6663 *** Paper size, paper orientation, columns
6664
6665 The variable `ps-paper-type' determines the size of paper ps-print
6666 formats for; it should contain one of the symbols:
6667 `a4' `a3' `letter' `legal' `letter-small' `tabloid'
6668 `ledger' `statement' `executive' `a4small' `b4' `b5'
6669 It defaults to `letter'.
6670 If you need other sizes, see the variable `ps-page-dimensions-database'.
6671
6672 The variable `ps-landscape-mode' determines the orientation
6673 of the printing on the page. nil, the default, means "portrait" mode,
6674 non-nil means "landscape" mode.
6675
6676 The variable `ps-number-of-columns' must be a positive integer.
6677 It determines the number of columns both in landscape and portrait mode.
6678 It defaults to 1.
6679
6680 *** Horizontal layout
6681
6682 The horizontal layout is determined by the variables
6683 `ps-left-margin', `ps-inter-column', and `ps-right-margin'.
6684 All are measured in points.
6685
6686 *** Vertical layout
6687
6688 The vertical layout is determined by the variables
6689 `ps-bottom-margin', `ps-top-margin', and `ps-header-offset'.
6690 All are measured in points.
6691
6692 *** Headers
6693
6694 If the variable `ps-print-header' is nil, no header is printed. Then
6695 `ps-header-offset' is not relevant and `ps-top-margin' represents the
6696 margin above the text.
6697
6698 If the variable `ps-print-header-frame' is non-nil, a gaudy
6699 framing box is printed around the header.
6700
6701 The contents of the header are determined by `ps-header-lines',
6702 `ps-show-n-of-n', `ps-left-header' and `ps-right-header'.
6703
6704 The height of the header is determined by `ps-header-line-pad',
6705 `ps-header-font-family', `ps-header-title-font-size' and
6706 `ps-header-font-size'.
6707
6708 *** Font managing
6709
6710 The variable `ps-font-family' determines which font family is to be
6711 used for ordinary text. Its value must be a key symbol in the alist
6712 `ps-font-info-database'. You can add other font families by adding
6713 elements to this alist.
6714
6715 The variable `ps-font-size' determines the size of the font
6716 for ordinary text. It defaults to 8.5 points.
6717
6718 ** hideshow changes.
6719
6720 *** now supports hiding of blocks of single line comments (like // for
6721 C++, ; for lisp).
6722
6723 *** Support for java-mode added.
6724
6725 *** When doing `hs-hide-all' it is now possible to also hide the comments
6726 in the file if `hs-hide-comments-when-hiding-all' is set.
6727
6728 *** The new function `hs-hide-initial-comment' hides the the comments at
6729 the beginning of the files. Finally those huge RCS logs don't stay in your
6730 way! This is run by default when entering the `hs-minor-mode'.
6731
6732 *** Now uses overlays instead of `selective-display', so is more
6733 robust and a lot faster.
6734
6735 *** A block beginning can span multiple lines.
6736
6737 *** The new variable `hs-show-hidden-short-form' if t, directs hideshow
6738 to show only the beginning of a block when it is hidden. See the
6739 documentation for more details.
6740
6741 ** Changes in Enriched mode.
6742
6743 *** When you visit a file in enriched-mode, Emacs will make sure it is
6744 filled to the current fill-column. This behavior is now independent
6745 of the size of the window. When you save the file, the fill-column in
6746 use is stored as well, so that the whole buffer need not be refilled
6747 the next time unless the fill-column is different.
6748
6749 *** use-hard-newlines is now a minor mode. When it is enabled, Emacs
6750 distinguishes between hard and soft newlines, and treats hard newlines
6751 as paragraph boundaries. Otherwise all newlines inserted are marked
6752 as soft, and paragraph boundaries are determined solely from the text.
6753
6754 ** Font Lock mode
6755
6756 *** Custom support
6757
6758 The variables font-lock-face-attributes, font-lock-display-type and
6759 font-lock-background-mode are now obsolete; the recommended way to specify the
6760 faces to use for Font Lock mode is with M-x customize-group on the new custom
6761 group font-lock-highlighting-faces. If you set font-lock-face-attributes in
6762 your ~/.emacs file, Font Lock mode will respect its value. However, you should
6763 consider converting from setting that variable to using M-x customize.
6764
6765 You can still use X resources to specify Font Lock face appearances.
6766
6767 *** Maximum decoration
6768
6769 Fontification now uses the maximum level of decoration supported by
6770 default. Previously, fontification used a mode-specific default level
6771 of decoration, which is typically the minimum level of decoration
6772 supported. You can set font-lock-maximum-decoration to nil
6773 to get the old behavior.
6774
6775 *** New support
6776
6777 Support is now provided for Java, Objective-C, AWK and SIMULA modes.
6778
6779 Note that Font Lock mode can be turned on without knowing exactly what modes
6780 support Font Lock mode, via the command global-font-lock-mode.
6781
6782 *** Configurable support
6783
6784 Support for C, C++, Objective-C and Java can be more easily configured for
6785 additional types and classes via the new variables c-font-lock-extra-types,
6786 c++-font-lock-extra-types, objc-font-lock-extra-types and, you guessed it,
6787 java-font-lock-extra-types. These value of each of these variables should be a
6788 list of regexps matching the extra type names. For example, the default value
6789 of c-font-lock-extra-types is ("\\sw+_t") which means fontification follows the
6790 convention that C type names end in _t. This results in slower fontification.
6791
6792 Of course, you can change the variables that specify fontification in whatever
6793 way you wish, typically by adding regexps. However, these new variables make
6794 it easier to make specific and common changes for the fontification of types.
6795
6796 *** Adding highlighting patterns to existing support
6797
6798 You can use the new function font-lock-add-keywords to add your own
6799 highlighting patterns, such as for project-local or user-specific constructs,
6800 for any mode.
6801
6802 For example, to highlight `FIXME:' words in C comments, put:
6803
6804 (font-lock-add-keywords 'c-mode '(("\\<FIXME:" 0 font-lock-warning-face t)))
6805
6806 in your ~/.emacs.
6807
6808 *** New faces
6809
6810 Font Lock now defines two new faces, font-lock-builtin-face and
6811 font-lock-warning-face. These are intended to highlight builtin keywords,
6812 distinct from a language's normal keywords, and objects that should be brought
6813 to user attention, respectively. Various modes now use these new faces.
6814
6815 *** Changes to fast-lock support mode
6816
6817 The fast-lock package, one of the two Font Lock support modes, can now process
6818 cache files silently. You can use the new variable fast-lock-verbose, in the
6819 same way as font-lock-verbose, to control this feature.
6820
6821 *** Changes to lazy-lock support mode
6822
6823 The lazy-lock package, one of the two Font Lock support modes, can now fontify
6824 according to the true syntactic context relative to other lines. You can use
6825 the new variable lazy-lock-defer-contextually to control this feature. If
6826 non-nil, changes to the buffer will cause subsequent lines in the buffer to be
6827 refontified after lazy-lock-defer-time seconds of idle time. If nil, then only
6828 the modified lines will be refontified; this is the same as the previous Lazy
6829 Lock mode behaviour and the behaviour of Font Lock mode.
6830
6831 This feature is useful in modes where strings or comments can span lines.
6832 For example, if a string or comment terminating character is deleted, then if
6833 this feature is enabled subsequent lines in the buffer will be correctly
6834 refontified to reflect their new syntactic context. Previously, only the line
6835 containing the deleted character would be refontified and you would have to use
6836 the command M-g M-g (font-lock-fontify-block) to refontify some lines.
6837
6838 As a consequence of this new feature, two other variables have changed:
6839
6840 Variable `lazy-lock-defer-driven' is renamed `lazy-lock-defer-on-scrolling'.
6841 Variable `lazy-lock-defer-time' can now only be a time, i.e., a number.
6842 Buffer modes for which on-the-fly deferral applies can be specified via the
6843 new variable `lazy-lock-defer-on-the-fly'.
6844
6845 If you set these variables in your ~/.emacs, then you may have to change those
6846 settings.
6847
6848 ** Ada mode changes.
6849
6850 *** There is now better support for using find-file.el with Ada mode.
6851 If you switch between spec and body, the cursor stays in the same
6852 procedure (modulo overloading). If a spec has no body file yet, but
6853 you try to switch to its body file, Ada mode now generates procedure
6854 stubs.
6855
6856 *** There are two new commands:
6857 - `ada-make-local' : invokes gnatmake on the current buffer
6858 - `ada-check-syntax' : check syntax of current buffer.
6859
6860 The user options `ada-compiler-make', `ada-make-options',
6861 `ada-language-version', `ada-compiler-syntax-check', and
6862 `ada-compile-options' are used within these commands.
6863
6864 *** Ada mode can now work with Outline minor mode. The outline level
6865 is calculated from the indenting, not from syntactic constructs.
6866 Outlining does not work if your code is not correctly indented.
6867
6868 *** The new function `ada-gnat-style' converts the buffer to the style of
6869 formatting used in GNAT. It places two blanks after a comment start,
6870 places one blank between a word end and an opening '(', and puts one
6871 space between a comma and the beginning of a word.
6872
6873 ** Scheme mode changes.
6874
6875 *** Scheme mode indentation now uses many of the facilities of Lisp
6876 mode; therefore, the variables to customize it are the variables used
6877 for Lisp mode which have names starting with `lisp-'. The variables
6878 with names starting with `scheme-' which used to do this no longer
6879 have any effect.
6880
6881 If you want to use different indentation for Scheme and Lisp, this is
6882 still possible, but now you must do it by adding a hook to
6883 scheme-mode-hook, which could work by setting the `lisp-' indentation
6884 variables as buffer-local variables.
6885
6886 *** DSSSL mode is a variant of Scheme mode, for editing DSSSL scripts.
6887 Use M-x dsssl-mode.
6888
6889 ** Changes to the emacsclient program
6890
6891 *** If a socket can't be found, and environment variables LOGNAME or
6892 USER are set, emacsclient now looks for a socket based on the UID
6893 associated with the name. That is an emacsclient running as root
6894 can connect to an Emacs server started by a non-root user.
6895
6896 *** The emacsclient program now accepts an option --no-wait which tells
6897 it to return immediately without waiting for you to "finish" the
6898 buffer in Emacs.
6899
6900 *** The new option --alternate-editor allows to specify an editor to
6901 use if Emacs is not running. The environment variable
6902 ALTERNATE_EDITOR can be used for the same effect; the command line
6903 option takes precedence.
6904
6905 ** M-x eldoc-mode enables a minor mode in which the echo area
6906 constantly shows the parameter list for function being called at point
6907 (in Emacs Lisp and Lisp Interaction modes only).
6908
6909 ** C-x n d now runs the new command narrow-to-defun,
6910 which narrows the accessible parts of the buffer to just
6911 the current defun.
6912
6913 ** Emacs now handles the `--' argument in the standard way; all
6914 following arguments are treated as ordinary file names.
6915
6916 ** On MSDOS and Windows, the bookmark file is now called _emacs.bmk,
6917 and the saved desktop file is now called _emacs.desktop (truncated if
6918 necessary).
6919
6920 ** When you kill a buffer that visits a file,
6921 if there are any registers that save positions in the file,
6922 these register values no longer become completely useless.
6923 If you try to go to such a register with C-x j, then you are
6924 asked whether to visit the file again. If you say yes,
6925 it visits the file and then goes to the same position.
6926
6927 ** When you visit a file that changes frequently outside Emacs--for
6928 example, a log of output from a process that continues to run--it may
6929 be useful for Emacs to revert the file without querying you whenever
6930 you visit the file afresh with C-x C-f.
6931
6932 You can request this behavior for certain files by setting the
6933 variable revert-without-query to a list of regular expressions. If a
6934 file's name matches any of these regular expressions, find-file and
6935 revert-buffer revert the buffer without asking for permission--but
6936 only if you have not edited the buffer text yourself.
6937
6938 ** set-default-font has been renamed to set-frame-font
6939 since it applies only to the current frame.
6940
6941 ** In TeX mode, you can use the variable tex-main-file to specify the
6942 file for tex-file to run TeX on. (By default, tex-main-file is nil,
6943 and tex-file runs TeX on the current visited file.)
6944
6945 This is useful when you are editing a document that consists of
6946 multiple files. In each of the included files, you can set up a local
6947 variable list which specifies the top-level file of your document for
6948 tex-main-file. Then tex-file will run TeX on the whole document
6949 instead of just the file you are editing.
6950
6951 ** RefTeX mode
6952
6953 RefTeX mode is a new minor mode with special support for \label, \ref
6954 and \cite macros in LaTeX documents. RefTeX distinguishes labels of
6955 different environments (equation, figure, ...) and has full support for
6956 multifile documents. To use it, select a buffer with a LaTeX document and
6957 turn the mode on with M-x reftex-mode. Here are the main user commands:
6958
6959 C-c ( reftex-label
6960 Creates a label semi-automatically. RefTeX is context sensitive and
6961 knows which kind of label is needed.
6962
6963 C-c ) reftex-reference
6964 Offers in a menu all labels in the document, along with context of the
6965 label definition. The selected label is referenced as \ref{LABEL}.
6966
6967 C-c [ reftex-citation
6968 Prompts for a regular expression and displays a list of matching BibTeX
6969 database entries. The selected entry is cited with a \cite{KEY} macro.
6970
6971 C-c & reftex-view-crossref
6972 Views the cross reference of a \ref or \cite command near point.
6973
6974 C-c = reftex-toc
6975 Shows a table of contents of the (multifile) document. From there you
6976 can quickly jump to every section.
6977
6978 Under X, RefTeX installs a "Ref" menu in the menu bar, with additional
6979 commands. Press `?' to get help when a prompt mentions this feature.
6980 Full documentation and customization examples are in the file
6981 reftex.el. You can use the finder to view the file documentation:
6982 C-h p --> tex --> reftex.el
6983
6984 ** Changes in BibTeX mode.
6985
6986 *** Info documentation is now available.
6987
6988 *** Don't allow parentheses in string constants anymore. This confused
6989 both the BibTeX program and Emacs BibTeX mode.
6990
6991 *** Renamed variable bibtex-mode-user-optional-fields to
6992 bibtex-user-optional-fields.
6993
6994 *** Removed variable bibtex-include-OPTannote
6995 (use bibtex-user-optional-fields instead).
6996
6997 *** New interactive functions to copy and kill fields and complete
6998 entries to the BibTeX kill ring, from where they can be yanked back by
6999 appropriate functions.
7000
7001 *** New interactive functions for repositioning and marking of
7002 entries. They are bound by default to M-C-l and M-C-h.
7003
7004 *** New hook bibtex-clean-entry-hook. It is called after entry has
7005 been cleaned.
7006
7007 *** New variable bibtex-field-delimiters, which replaces variables
7008 bibtex-field-{left|right}-delimiter.
7009
7010 *** New variable bibtex-entry-delimiters to determine how entries
7011 shall be delimited.
7012
7013 *** Allow preinitialization of fields. See documentation of
7014 bibtex-user-optional-fields, bibtex-entry-field-alist, and
7015 bibtex-include-OPTkey for details.
7016
7017 *** Book and InBook entries require either an author or an editor
7018 field. This is now supported by bibtex.el. Alternative fields are
7019 prefixed with `ALT'.
7020
7021 *** New variable bibtex-entry-format, which replaces variable
7022 bibtex-clean-entry-zap-empty-opts and allows specification of many
7023 formatting options performed on cleaning an entry (see variable
7024 documentation).
7025
7026 *** Even more control on how automatic keys are generated. See
7027 documentation of bibtex-generate-autokey for details. Transcriptions
7028 for foreign languages other than German are now handled, too.
7029
7030 *** New boolean user option bibtex-comma-after-last-field to decide if
7031 comma should be inserted at end of last field.
7032
7033 *** New boolean user option bibtex-align-at-equal-sign to determine if
7034 alignment should be made at left side of field contents or at equal
7035 signs. New user options to control entry layout (e.g. indentation).
7036
7037 *** New function bibtex-fill-entry to realign entries.
7038
7039 *** New function bibtex-reformat to reformat region or buffer.
7040
7041 *** New function bibtex-convert-alien to convert a BibTeX database
7042 from alien sources.
7043
7044 *** New function bibtex-complete-key (similar to bibtex-complete-string)
7045 to complete prefix to a key defined in buffer. Mainly useful in
7046 crossref entries.
7047
7048 *** New function bibtex-count-entries to count entries in buffer or
7049 region.
7050
7051 *** Added support for imenu.
7052
7053 *** The function `bibtex-validate' now checks current region instead
7054 of buffer if mark is active. Now it shows all errors of buffer in a
7055 `compilation mode' buffer. You can use the normal commands (e.g.
7056 `next-error') for compilation modes to jump to errors.
7057
7058 *** New variable `bibtex-string-file-path' to determine where the files
7059 from `bibtex-string-files' are searched.
7060
7061 ** Iso Accents mode now supports Latin-3 as an alternative.
7062
7063 ** The command next-error now opens blocks hidden by hideshow.
7064
7065 ** The function using-unix-filesystems has been replaced by the
7066 functions add-untranslated-filesystem and remove-untranslated-filesystem.
7067 Each of these functions takes the name of a drive letter or directory
7068 as an argument.
7069
7070 When a filesystem is added as untranslated, all files on it are read
7071 and written in binary mode (no cr/lf translation is performed).
7072
7073 ** browse-url changes
7074
7075 *** New methods for: Grail (browse-url-generic), MMM (browse-url-mmm),
7076 Lynx in a separate xterm (browse-url-lynx-xterm) or in an Emacs window
7077 (browse-url-lynx-emacs), remote W3 (browse-url-w3-gnudoit), generic
7078 non-remote-controlled browsers (browse-url-generic) and associated
7079 customization variables.
7080
7081 *** New commands `browse-url-of-region' and `browse-url'.
7082
7083 *** URLs marked up with <URL:...> (RFC1738) work if broken across
7084 lines. Browsing methods can be associated with URL regexps
7085 (e.g. mailto: URLs) via `browse-url-browser-function'.
7086
7087 ** Changes in Ediff
7088
7089 *** Clicking Mouse-2 on a brief command description in Ediff control panel
7090 pops up the Info file for this command.
7091
7092 *** There is now a variable, ediff-autostore-merges, which controls whether
7093 the result of a merge is saved in a file. By default, this is done only when
7094 merge is done from a session group (eg, when merging files in two different
7095 directories).
7096
7097 *** Since Emacs 19.31 (this hasn't been announced before), Ediff can compare
7098 and merge groups of files residing in different directories, or revisions of
7099 files in the same directory.
7100
7101 *** Since Emacs 19.31, Ediff can apply multi-file patches interactively.
7102 The patches must be in the context format or GNU unified format. (The bug
7103 related to the GNU format has now been fixed.)
7104
7105 ** Changes in Viper
7106
7107 *** The startup file is now .viper instead of .vip
7108 *** All variable/function names have been changed to start with viper-
7109 instead of vip-.
7110 *** C-\ now simulates the meta-key in all Viper states.
7111 *** C-z in Insert state now escapes to Vi for the duration of the next
7112 Viper command. In Vi and Insert states, C-z behaves as before.
7113 *** C-c \ escapes to Vi for one command if Viper is in Insert or Emacs states.
7114 *** _ is no longer the meta-key in Vi state.
7115 *** The variable viper-insert-state-cursor-color can be used to change cursor
7116 color when Viper is in insert state.
7117 *** If search lands the cursor near the top or the bottom of the window,
7118 Viper pulls the window up or down to expose more context. The variable
7119 viper-adjust-window-after-search controls this behavior.
7120
7121 ** Etags changes.
7122
7123 *** In C, C++, Objective C and Java, Etags tags global variables by
7124 default. The resulting tags files are inflated by 30% on average.
7125 Use --no-globals to turn this feature off. Etags can also tag
7126 variables which are members of structure-like constructs, but it does
7127 not by default. Use --members to turn this feature on.
7128
7129 *** C++ member functions are now recognized as tags.
7130
7131 *** Java is tagged like C++. In addition, "extends" and "implements"
7132 constructs are tagged. Files are recognised by the extension .java.
7133
7134 *** Etags can now handle programs written in Postscript. Files are
7135 recognised by the extensions .ps and .pdb (Postscript with C syntax).
7136 In Postscript, tags are lines that start with a slash.
7137
7138 *** Etags now handles Objective C and Objective C++ code. The usual C and
7139 C++ tags are recognized in these languages; in addition, etags
7140 recognizes special Objective C syntax for classes, class categories,
7141 methods and protocols.
7142
7143 *** Etags also handles Cobol. Files are recognised by the extension
7144 .cobol. The tagged lines are those containing a word that begins in
7145 column 8 and ends in a full stop, i.e. anything that could be a
7146 paragraph name.
7147
7148 *** Regexps in Etags now support intervals, as in ed or grep. The syntax of
7149 an interval is \{M,N\}, and it means to match the preceding expression
7150 at least M times and as many as N times.
7151
7152 ** The format for specifying a custom format for time-stamp to insert
7153 in files has changed slightly.
7154
7155 With the new enhancements to the functionality of format-time-string,
7156 time-stamp-format will change to be eventually compatible with it.
7157 This conversion is being done in two steps to maintain compatibility
7158 with old time-stamp-format values.
7159
7160 In the new scheme, alternate case is signified by the number-sign
7161 (`#') modifier, rather than changing the case of the format character.
7162 This feature is as yet incompletely implemented for compatibility
7163 reasons.
7164
7165 In the old time-stamp-format, all numeric fields defaulted to their
7166 natural width. (With format-time-string, each format has a
7167 fixed-width default.) In this version, you can specify the colon
7168 (`:') modifier to a numeric conversion to mean "give me the historical
7169 time-stamp-format width default." Do not use colon if you are
7170 specifying an explicit width, as in "%02d".
7171
7172 Numbers are no longer truncated to the requested width, except in the
7173 case of "%02y", which continues to give a two-digit year. Digit
7174 truncation probably wasn't being used for anything else anyway.
7175
7176 The new formats will work with old versions of Emacs. New formats are
7177 being recommended now to allow time-stamp-format to change in the
7178 future to be compatible with format-time-string. The new forms being
7179 recommended now will continue to work then.
7180
7181 See the documentation string for the variable time-stamp-format for
7182 details.
7183
7184 ** There are some additional major modes:
7185
7186 dcl-mode, for editing VMS DCL files.
7187 m4-mode, for editing files of m4 input.
7188 meta-mode, for editing MetaFont and MetaPost source files.
7189
7190 ** In Shell mode, the command shell-copy-environment-variable lets you
7191 copy the value of a specified environment variable from the subshell
7192 into Emacs.
7193
7194 ** New Lisp packages include:
7195
7196 *** battery.el displays battery status for laptops.
7197
7198 *** M-x bruce (named after Lenny Bruce) is a program that might
7199 be used for adding some indecent words to your email.
7200
7201 *** M-x crisp-mode enables an emulation for the CRiSP editor.
7202
7203 *** M-x dirtrack arranges for better tracking of directory changes
7204 in shell buffers.
7205
7206 *** The new library elint.el provides for linting of Emacs Lisp code.
7207 See the documentation for `elint-initialize', `elint-current-buffer'
7208 and `elint-defun'.
7209
7210 *** M-x expand-add-abbrevs defines a special kind of abbrev which is
7211 meant for programming constructs. These abbrevs expand like ordinary
7212 ones, when you type SPC, but only at the end of a line and not within
7213 strings or comments.
7214
7215 These abbrevs can act as templates: you can define places within an
7216 abbrev for insertion of additional text. Once you expand the abbrev,
7217 you can then use C-x a p and C-x a n to move back and forth to these
7218 insertion points. Thus you can conveniently insert additional text
7219 at these points.
7220
7221 *** filecache.el remembers the location of files so that you
7222 can visit them by short forms of their names.
7223
7224 *** find-func.el lets you find the definition of the user-loaded
7225 Emacs Lisp function at point.
7226
7227 *** M-x handwrite converts text to a "handwritten" picture.
7228
7229 *** M-x iswitchb-buffer is a command for switching to a buffer, much like
7230 switch-buffer, but it reads the argument in a more helpful way.
7231
7232 *** M-x landmark implements a neural network for landmark learning.
7233
7234 *** M-x locate provides a convenient interface to the `locate' program.
7235
7236 *** M4 mode is a new mode for editing files of m4 input.
7237
7238 *** mantemp.el creates C++ manual template instantiations
7239 from the GCC error messages which indicate which instantiations are needed.
7240
7241 *** mouse-copy.el provides a one-click copy and move feature.
7242 You can drag a region with M-mouse-1, and it is automatically
7243 inserted at point. M-Shift-mouse-1 deletes the text from its
7244 original place after inserting the copy.
7245
7246 *** mouse-drag.el lets you do scrolling by dragging Mouse-2
7247 on the buffer.
7248
7249 You click the mouse and move; that distance either translates into the
7250 velocity to scroll (with mouse-drag-throw) or the distance to scroll
7251 (with mouse-drag-drag). Horizontal scrolling is enabled when needed.
7252
7253 Enable mouse-drag with:
7254 (global-set-key [down-mouse-2] 'mouse-drag-throw)
7255 -or-
7256 (global-set-key [down-mouse-2] 'mouse-drag-drag)
7257
7258 *** mspools.el is useful for determining which mail folders have
7259 mail waiting to be read in them. It works with procmail.
7260
7261 *** Octave mode is a major mode for editing files of input for Octave.
7262 It comes with a facility for communicating with an Octave subprocess.
7263
7264 *** ogonek
7265
7266 The ogonek package provides functions for changing the coding of
7267 Polish diacritic characters in buffers. Codings known from various
7268 platforms are supported such as ISO8859-2, Mazovia, IBM Latin2, and
7269 TeX. For example, you can change the coding from Mazovia to
7270 ISO8859-2. Another example is a change of coding from ISO8859-2 to
7271 prefix notation (in which `/a' stands for the aogonek character, for
7272 instance) and vice versa.
7273
7274 To use this package load it using
7275 M-x load-library [enter] ogonek
7276 Then, you may get an explanation by calling one of
7277 M-x ogonek-jak -- in Polish
7278 M-x ogonek-how -- in English
7279 The info specifies the commands and variables provided as well as the
7280 ways of customization in `.emacs'.
7281
7282 *** Interface to ph.
7283
7284 Emacs provides a client interface to CCSO Nameservers (ph/qi)
7285
7286 The CCSO nameserver is used in many universities to provide directory
7287 services about people. ph.el provides a convenient Emacs interface to
7288 these servers.
7289
7290 *** uce.el is useful for replying to unsolicited commercial email.
7291
7292 *** vcursor.el implements a "virtual cursor" feature.
7293 You can move the virtual cursor with special commands
7294 while the real cursor does not move.
7295
7296 *** webjump.el is a "hot list" package which you can set up
7297 for visiting your favorite web sites.
7298
7299 *** M-x winner-mode is a minor mode which saves window configurations,
7300 so you can move back to other configurations that you have recently used.
7301
7302 ** movemail change
7303
7304 Movemail no longer needs to be installed setuid root in order for POP
7305 mail retrieval to function properly. This is because it no longer
7306 supports the RPOP (reserved-port POP) protocol; instead, it uses the
7307 user's POP password to authenticate to the mail server.
7308
7309 This change was made earlier, but not reported in NEWS before.
7310 \f
7311 * Emacs 20.1 changes for MS-DOS and MS-Windows.
7312
7313 ** Changes in handling MS-DOS/MS-Windows text files.
7314
7315 Emacs handles three different conventions for representing
7316 end-of-line: CRLF for MSDOS, LF for Unix and GNU, and CR (used on the
7317 Macintosh). Emacs determines which convention is used in a specific
7318 file based on the contents of that file (except for certain special
7319 file names), and when it saves the file, it uses the same convention.
7320
7321 To save the file and change the end-of-line convention, you can use
7322 C-x RET f (set-buffer-file-coding-system) to specify a different
7323 coding system for the buffer. Then, when you save the file, the newly
7324 specified coding system will take effect. For example, to save with
7325 LF, specify undecided-unix (or some other ...-unix coding system); to
7326 save with CRLF, specify undecided-dos.
7327 \f
7328 * Lisp Changes in Emacs 20.1
7329
7330 ** Byte-compiled files made with Emacs 20 will, in general, work in
7331 Emacs 19 as well, as long as the source code runs in Emacs 19. And
7332 vice versa: byte-compiled files made with Emacs 19 should also run in
7333 Emacs 20, as long as the program itself works in Emacs 20.
7334
7335 ** Windows-specific functions and variables have been renamed
7336 to start with w32- instead of win32-.
7337
7338 In hacker language, calling something a "win" is a form of praise. We
7339 don't want to praise a non-free Microsoft system, so we don't call it
7340 "win".
7341
7342 ** Basic Lisp changes
7343
7344 *** A symbol whose name starts with a colon now automatically
7345 evaluates to itself. Therefore such a symbol can be used as a constant.
7346
7347 *** The defined purpose of `defconst' has been changed. It should now
7348 be used only for values that should not be changed whether by a program
7349 or by the user.
7350
7351 The actual behavior of defconst has not been changed.
7352
7353 *** There are new macros `when' and `unless'
7354
7355 (when CONDITION BODY...) is short for (if CONDITION (progn BODY...))
7356 (unless CONDITION BODY...) is short for (if CONDITION nil BODY...)
7357
7358 *** Emacs now defines functions caar, cadr, cdar and cddr with their
7359 usual Lisp meanings. For example, caar returns the car of the car of
7360 its argument.
7361
7362 *** equal, when comparing strings, now ignores their text properties.
7363
7364 *** The new function `functionp' tests whether an object is a function.
7365
7366 *** arrayp now returns t for char-tables and bool-vectors.
7367
7368 *** Certain primitives which use characters (as integers) now get an
7369 error if the integer is not a valid character code. These primitives
7370 include insert-char, char-to-string, and the %c construct in the
7371 `format' function.
7372
7373 *** The `require' function now insists on adding a suffix, either .el
7374 or .elc, to the file name. Thus, (require 'foo) will not use a file
7375 whose name is just foo. It insists on foo.el or foo.elc.
7376
7377 *** The `autoload' function, when the file name does not contain
7378 either a directory name or the suffix .el or .elc, insists on
7379 adding one of these suffixes.
7380
7381 *** string-to-number now takes an optional second argument BASE
7382 which specifies the base to use when converting an integer.
7383 If BASE is omitted, base 10 is used.
7384
7385 We have not implemented other radices for floating point numbers,
7386 because that would be much more work and does not seem useful.
7387
7388 *** substring now handles vectors as well as strings.
7389
7390 *** The Common Lisp function eql is no longer defined normally.
7391 You must load the `cl' library to define it.
7392
7393 *** The new macro `with-current-buffer' lets you evaluate an expression
7394 conveniently with a different current buffer. It looks like this:
7395
7396 (with-current-buffer BUFFER BODY-FORMS...)
7397
7398 BUFFER is the expression that says which buffer to use.
7399 BODY-FORMS say what to do in that buffer.
7400
7401 *** The new primitive `save-current-buffer' saves and restores the
7402 choice of current buffer, like `save-excursion', but without saving or
7403 restoring the value of point or the mark. `with-current-buffer'
7404 works using `save-current-buffer'.
7405
7406 *** The new macro `with-temp-file' lets you do some work in a new buffer and
7407 write the output to a specified file. Like `progn', it returns the value
7408 of the last form.
7409
7410 *** The new macro `with-temp-buffer' lets you do some work in a new buffer,
7411 which is discarded after use. Like `progn', it returns the value of the
7412 last form. If you wish to return the buffer contents, use (buffer-string)
7413 as the last form.
7414
7415 *** The new function split-string takes a string, splits it at certain
7416 characters, and returns a list of the substrings in between the
7417 matches.
7418
7419 For example, (split-string "foo bar lose" " +") returns ("foo" "bar" "lose").
7420
7421 *** The new macro with-output-to-string executes some Lisp expressions
7422 with standard-output set up so that all output feeds into a string.
7423 Then it returns that string.
7424
7425 For example, if the current buffer name is `foo',
7426
7427 (with-output-to-string
7428 (princ "The buffer is ")
7429 (princ (buffer-name)))
7430
7431 returns "The buffer is foo".
7432
7433 ** Non-ASCII characters are now supported, if enable-multibyte-characters
7434 is non-nil.
7435
7436 These characters have character codes above 256. When inserted in the
7437 buffer or stored in a string, they are represented as multibyte
7438 characters that occupy several buffer positions each.
7439
7440 *** When enable-multibyte-characters is non-nil, a single character in
7441 a buffer or string can be two or more bytes (as many as four).
7442
7443 Buffers and strings are still made up of unibyte elements;
7444 character positions and string indices are always measured in bytes.
7445 Therefore, moving forward one character can increase the buffer
7446 position by 2, 3 or 4. The function forward-char moves by whole
7447 characters, and therefore is no longer equivalent to
7448 (lambda (n) (goto-char (+ (point) n))).
7449
7450 ASCII characters (codes 0 through 127) are still single bytes, always.
7451 Sequences of byte values 128 through 255 are used to represent
7452 non-ASCII characters. These sequences are called "multibyte
7453 characters".
7454
7455 The first byte of a multibyte character is always in the range 128
7456 through 159 (octal 0200 through 0237). These values are called
7457 "leading codes". The second and subsequent bytes are always in the
7458 range 160 through 255 (octal 0240 through 0377). The first byte, the
7459 leading code, determines how many bytes long the sequence is.
7460
7461 *** The function forward-char moves over characters, and therefore
7462 (forward-char 1) may increase point by more than 1 if it moves over a
7463 multibyte character. Likewise, delete-char always deletes a
7464 character, which may be more than one buffer position.
7465
7466 This means that some Lisp programs, which assume that a character is
7467 always one buffer position, need to be changed.
7468
7469 However, all ASCII characters are always one buffer position.
7470
7471 *** The regexp [\200-\377] no longer matches all non-ASCII characters,
7472 because when enable-multibyte-characters is non-nil, these characters
7473 have codes that are not in the range octal 200 to octal 377. However,
7474 the regexp [^\000-\177] does match all non-ASCII characters,
7475 guaranteed.
7476
7477 *** The function char-boundary-p returns non-nil if position POS is
7478 between two characters in the buffer (not in the middle of a
7479 character).
7480
7481 When the value is non-nil, it says what kind of character follows POS:
7482
7483 0 if POS is at an ASCII character or at the end of range,
7484 1 if POS is before a 2-byte length multi-byte form,
7485 2 if POS is at a head of 3-byte length multi-byte form,
7486 3 if POS is at a head of 4-byte length multi-byte form,
7487 4 if POS is at a head of multi-byte form of a composite character.
7488
7489 *** The function char-bytes returns how many bytes the character CHAR uses.
7490
7491 *** Strings can contain multibyte characters. The function
7492 `length' returns the string length counting bytes, which may be
7493 more than the number of characters.
7494
7495 You can include a multibyte character in a string constant by writing
7496 it literally. You can also represent it with a hex escape,
7497 \xNNNNNNN..., using as many digits as necessary. Any character which
7498 is not a valid hex digit terminates this construct. If you want to
7499 follow it with a character that is a hex digit, write backslash and
7500 newline in between; that will terminate the hex escape.
7501
7502 *** The function concat-chars takes arguments which are characters
7503 and returns a string containing those characters.
7504
7505 *** The function sref access a multibyte character in a string.
7506 (sref STRING INDX) returns the character in STRING at INDEX. INDEX
7507 counts from zero. If INDEX is at a position in the middle of a
7508 character, sref signals an error.
7509
7510 *** The function chars-in-string returns the number of characters
7511 in a string. This is less than the length of the string, if the
7512 string contains multibyte characters (the length counts bytes).
7513
7514 *** The function chars-in-region returns the number of characters
7515 in a region from BEG to END. This is less than (- END BEG) if the
7516 region contains multibyte characters (the length counts bytes).
7517
7518 *** The function string-to-list converts a string to a list of
7519 the characters in it. string-to-vector converts a string
7520 to a vector of the characters in it.
7521
7522 *** The function store-substring alters part of the contents
7523 of a string. You call it as follows:
7524
7525 (store-substring STRING IDX OBJ)
7526
7527 This says to alter STRING, by storing OBJ starting at index IDX in
7528 STRING. OBJ may be either a character or a (smaller) string.
7529 This function really does alter the contents of STRING.
7530 Since it is impossible to change the length of an existing string,
7531 it is an error if OBJ doesn't fit within STRING's actual length.
7532
7533 *** char-width returns the width (in columns) of the character CHAR,
7534 if it were displayed in the current buffer and the selected window.
7535
7536 *** string-width returns the width (in columns) of the text in STRING,
7537 if it were displayed in the current buffer and the selected window.
7538
7539 *** truncate-string-to-width shortens a string, if necessary,
7540 to fit within a certain number of columns. (Of course, it does
7541 not alter the string that you give it; it returns a new string
7542 which contains all or just part of the existing string.)
7543
7544 (truncate-string-to-width STR END-COLUMN &optional START-COLUMN PADDING)
7545
7546 This returns the part of STR up to column END-COLUMN.
7547
7548 The optional argument START-COLUMN specifies the starting column.
7549 If this is non-nil, then the first START-COLUMN columns of the string
7550 are not included in the resulting value.
7551
7552 The optional argument PADDING, if non-nil, is a padding character to be added
7553 at the beginning and end the resulting string, to extend it to exactly
7554 WIDTH columns. If PADDING is nil, that means do not pad; then, if STRING
7555 is narrower than WIDTH, the value is equal to STRING.
7556
7557 If PADDING and START-COLUMN are both non-nil, and if there is no clean
7558 place in STRING that corresponds to START-COLUMN (because one
7559 character extends across that column), then the padding character
7560 PADDING is added one or more times at the beginning of the result
7561 string, so that its columns line up as if it really did start at
7562 column START-COLUMN.
7563
7564 *** When the functions in the list after-change-functions are called,
7565 the third argument is the number of bytes in the pre-change text, not
7566 necessarily the number of characters. It is, in effect, the
7567 difference in buffer position between the beginning and the end of the
7568 changed text, before the change.
7569
7570 *** The characters Emacs uses are classified in various character
7571 sets, each of which has a name which is a symbol. In general there is
7572 one character set for each script, not for each language.
7573
7574 **** The function charsetp tests whether an object is a character set name.
7575
7576 **** The variable charset-list holds a list of character set names.
7577
7578 **** char-charset, given a character code, returns the name of the character
7579 set that the character belongs to. (The value is a symbol.)
7580
7581 **** split-char, given a character code, returns a list containing the
7582 name of the character set, followed by one or two byte-values
7583 which identify the character within that character set.
7584
7585 **** make-char, given a character set name and one or two subsequent
7586 byte-values, constructs a character code. This is roughly the
7587 opposite of split-char.
7588
7589 **** find-charset-region returns a list of the character sets
7590 of all the characters between BEG and END.
7591
7592 **** find-charset-string returns a list of the character sets
7593 of all the characters in a string.
7594
7595 *** Here are the Lisp facilities for working with coding systems
7596 and specifying coding systems.
7597
7598 **** The function coding-system-list returns a list of all coding
7599 system names (symbols). With optional argument t, it returns a list
7600 of all distinct base coding systems, not including variants.
7601 (Variant coding systems are those like latin-1-dos, latin-1-unix
7602 and latin-1-mac which specify the end-of-line conversion as well
7603 as what to do about code conversion.)
7604
7605 **** coding-system-p tests a symbol to see if it is a coding system
7606 name. It returns t if so, nil if not.
7607
7608 **** file-coding-system-alist specifies which coding systems to use
7609 for certain file names. It works like network-coding-system-alist,
7610 except that the PATTERN is matched against the file name.
7611
7612 Each element has the format (PATTERN . VAL), where PATTERN determines
7613 which file names the element applies to. PATTERN should be a regexp
7614 to match against a file name.
7615
7616 VAL is a coding system, a cons cell containing two coding systems, or
7617 a function symbol. If VAL is a coding system, it is used for both
7618 decoding what received from the network stream and encoding what sent
7619 to the network stream. If VAL is a cons cell containing two coding
7620 systems, the car specifies the coding system for decoding, and the cdr
7621 specifies the coding system for encoding.
7622
7623 If VAL is a function symbol, the function must return a coding system
7624 or a cons cell containing two coding systems, which is used as above.
7625
7626 **** The variable network-coding-system-alist specifies
7627 the coding system to use for network sockets.
7628
7629 Each element has the format (PATTERN . VAL), where PATTERN determines
7630 which network sockets the element applies to. PATTERN should be
7631 either a port number or a regular expression matching some network
7632 service names.
7633
7634 VAL is a coding system, a cons cell containing two coding systems, or
7635 a function symbol. If VAL is a coding system, it is used for both
7636 decoding what received from the network stream and encoding what sent
7637 to the network stream. If VAL is a cons cell containing two coding
7638 systems, the car specifies the coding system for decoding, and the cdr
7639 specifies the coding system for encoding.
7640
7641 If VAL is a function symbol, the function must return a coding system
7642 or a cons cell containing two coding systems, which is used as above.
7643
7644 **** process-coding-system-alist specifies which coding systems to use
7645 for certain subprocess. It works like network-coding-system-alist,
7646 except that the PATTERN is matched against the program name used to
7647 start the subprocess.
7648
7649 **** The variable default-process-coding-system specifies the coding
7650 systems to use for subprocess (and net connection) input and output,
7651 when nothing else specifies what to do. The value is a cons cell
7652 (OUTPUT-CODING . INPUT-CODING). OUTPUT-CODING applies to output
7653 to the subprocess, and INPUT-CODING applies to input from it.
7654
7655 **** The variable coding-system-for-write, if non-nil, specifies the
7656 coding system to use for writing a file, or for output to a synchronous
7657 subprocess.
7658
7659 It also applies to any asynchronous subprocess or network connection,
7660 but in a different way: the value of coding-system-for-write when you
7661 start the subprocess or connection affects that subprocess or
7662 connection permanently or until overridden.
7663
7664 The variable coding-system-for-write takes precedence over
7665 file-coding-system-alist, process-coding-system-alist and
7666 network-coding-system-alist, and all other methods of specifying a
7667 coding system for output. But most of the time this variable is nil.
7668 It exists so that Lisp programs can bind it to a specific coding
7669 system for one operation at a time.
7670
7671 **** coding-system-for-read applies similarly to input from
7672 files, subprocesses or network connections.
7673
7674 **** The function process-coding-system tells you what
7675 coding systems(s) an existing subprocess is using.
7676 The value is a cons cell,
7677 (DECODING-CODING-SYSTEM . ENCODING-CODING-SYSTEM)
7678 where DECODING-CODING-SYSTEM is used for decoding output from
7679 the subprocess, and ENCODING-CODING-SYSTEM is used for encoding
7680 input to the subprocess.
7681
7682 **** The function set-process-coding-system can be used to
7683 change the coding systems in use for an existing subprocess.
7684
7685 ** Emacs has a new facility to help users manage the many
7686 customization options. To make a Lisp program work with this facility,
7687 you need to use the new macros defgroup and defcustom.
7688
7689 You use defcustom instead of defvar, for defining a user option
7690 variable. The difference is that you specify two additional pieces of
7691 information (usually): the "type" which says what values are
7692 legitimate, and the "group" which specifies the hierarchy for
7693 customization.
7694
7695 Thus, instead of writing
7696
7697 (defvar foo-blurgoze nil
7698 "*Non-nil means that foo will act very blurgozely.")
7699
7700 you would now write this:
7701
7702 (defcustom foo-blurgoze nil
7703 "*Non-nil means that foo will act very blurgozely."
7704 :type 'boolean
7705 :group foo)
7706
7707 The type `boolean' means that this variable has only
7708 two meaningful states: nil and non-nil. Other type values
7709 describe other possibilities; see the manual for Custom
7710 for a description of them.
7711
7712 The "group" argument is used to specify a group which the option
7713 should belong to. You define a new group like this:
7714
7715 (defgroup ispell nil
7716 "Spell checking using Ispell."
7717 :group 'processes)
7718
7719 The "group" argument in defgroup specifies the parent group. The root
7720 group is called `emacs'; it should not contain any variables itself,
7721 but only other groups. The immediate subgroups of `emacs' correspond
7722 to the keywords used by C-h p. Under these subgroups come
7723 second-level subgroups that belong to individual packages.
7724
7725 Each Emacs package should have its own set of groups. A simple
7726 package should have just one group; a more complex package should
7727 have a hierarchy of its own groups. The sole or root group of a
7728 package should be a subgroup of one or more of the "keyword"
7729 first-level subgroups.
7730
7731 ** New `widget' library for inserting UI components in buffers.
7732
7733 This library, used by the new custom library, is documented in a
7734 separate manual that accompanies Emacs.
7735
7736 ** easy-mmode
7737
7738 The easy-mmode package provides macros and functions that make
7739 developing minor modes easier. Roughly, the programmer has to code
7740 only the functionality of the minor mode. All the rest--toggles,
7741 predicate, and documentation--can be done in one call to the macro
7742 `easy-mmode-define-minor-mode' (see the documentation). See also
7743 `easy-mmode-define-keymap'.
7744
7745 ** Text property changes
7746
7747 *** The `intangible' property now works on overlays as well as on a
7748 text property.
7749
7750 *** The new functions next-char-property-change and
7751 previous-char-property-change scan through the buffer looking for a
7752 place where either a text property or an overlay might change. The
7753 functions take two arguments, POSITION and LIMIT. POSITION is the
7754 starting position for the scan. LIMIT says where to stop the scan.
7755
7756 If no property change is found before LIMIT, the value is LIMIT. If
7757 LIMIT is nil, scan goes to the beginning or end of the accessible part
7758 of the buffer. If no property change is found, the value is the
7759 position of the beginning or end of the buffer.
7760
7761 *** In the `local-map' text property or overlay property, the property
7762 value can now be a symbol whose function definition is a keymap. This
7763 is an alternative to using the keymap itself.
7764
7765 ** Changes in invisibility features
7766
7767 *** Isearch can now temporarily show parts of the buffer which are
7768 hidden by an overlay with a invisible property, when the search match
7769 is inside that portion of the buffer. To enable this the overlay
7770 should have a isearch-open-invisible property which is a function that
7771 would be called having the overlay as an argument, the function should
7772 make the overlay visible.
7773
7774 During incremental search the overlays are shown by modifying the
7775 invisible and intangible properties, if beside this more actions are
7776 needed the overlay should have a isearch-open-invisible-temporary
7777 which is a function. The function is called with 2 arguments: one is
7778 the overlay and the second is nil when it should show the overlay and
7779 t when it should hide it.
7780
7781 *** add-to-invisibility-spec, remove-from-invisibility-spec
7782
7783 Modes that use overlays to hide portions of a buffer should set the
7784 invisible property of the overlay to the mode's name (or another symbol)
7785 and modify the `buffer-invisibility-spec' to include that symbol.
7786 Use `add-to-invisibility-spec' and `remove-from-invisibility-spec' to
7787 manipulate the `buffer-invisibility-spec'.
7788 Here is an example of how to do this:
7789
7790 ;; If we want to display an ellipsis:
7791 (add-to-invisibility-spec '(my-symbol . t))
7792 ;; If you don't want ellipsis:
7793 (add-to-invisibility-spec 'my-symbol)
7794
7795 ...
7796 (overlay-put (make-overlay beginning end) 'invisible 'my-symbol)
7797
7798 ...
7799 ;; When done with the overlays:
7800 (remove-from-invisibility-spec '(my-symbol . t))
7801 ;; Or respectively:
7802 (remove-from-invisibility-spec 'my-symbol)
7803
7804 ** Changes in syntax parsing.
7805
7806 *** The syntax-directed buffer-scan functions (such as
7807 `parse-partial-sexp', `forward-word' and similar functions) can now
7808 obey syntax information specified by text properties, if the variable
7809 `parse-sexp-lookup-properties' is non-nil.
7810
7811 If the value of `parse-sexp-lookup-properties' is nil, the behavior
7812 is as before: the syntax-table of the current buffer is always
7813 used to determine the syntax of the character at the position.
7814
7815 When `parse-sexp-lookup-properties' is non-nil, the syntax of a
7816 character in the buffer is calculated thus:
7817
7818 a) if the `syntax-table' text-property of that character
7819 is a cons, this cons becomes the syntax-type;
7820
7821 Valid values of `syntax-table' text-property are: nil, a valid
7822 syntax-table, and a valid syntax-table element, i.e.,
7823 a cons cell of the form (SYNTAX-CODE . MATCHING-CHAR).
7824
7825 b) if the character's `syntax-table' text-property
7826 is a syntax table, this syntax table is used
7827 (instead of the syntax-table of the current buffer) to
7828 determine the syntax type of the character.
7829
7830 c) otherwise the syntax-type is determined by the syntax-table
7831 of the current buffer.
7832
7833 *** The meaning of \s in regular expressions is also affected by the
7834 value of `parse-sexp-lookup-properties'. The details are the same as
7835 for the syntax-directed buffer-scan functions.
7836
7837 *** There are two new syntax-codes, `!' and `|' (numeric values 14
7838 and 15). A character with a code `!' starts a comment which is ended
7839 only by another character with the same code (unless quoted). A
7840 character with a code `|' starts a string which is ended only by
7841 another character with the same code (unless quoted).
7842
7843 These codes are mainly meant for use as values of the `syntax-table'
7844 text property.
7845
7846 *** The function `parse-partial-sexp' has new semantics for the sixth
7847 arg COMMENTSTOP. If it is `syntax-table', parse stops after the start
7848 of a comment or a string, or after end of a comment or a string.
7849
7850 *** The state-list which the return value from `parse-partial-sexp'
7851 (and can also be used as an argument) now has an optional ninth
7852 element: the character address of the start of last comment or string;
7853 nil if none. The fourth and eighth elements have special values if the
7854 string/comment is started by a "!" or "|" syntax-code.
7855
7856 *** Since new features of `parse-partial-sexp' allow a complete
7857 syntactic parsing, `font-lock' no longer supports
7858 `font-lock-comment-start-regexp'.
7859
7860 ** Changes in face features
7861
7862 *** The face functions are now unconditionally defined in Emacs, even
7863 if it does not support displaying on a device that supports faces.
7864
7865 *** The function face-documentation returns the documentation string
7866 of a face (or nil if it doesn't have one).
7867
7868 *** The function face-bold-p returns t if a face should be bold.
7869 set-face-bold-p sets that flag.
7870
7871 *** The function face-italic-p returns t if a face should be italic.
7872 set-face-italic-p sets that flag.
7873
7874 *** You can now specify foreground and background colors for text
7875 by adding elements of the form (foreground-color . COLOR-NAME)
7876 and (background-color . COLOR-NAME) to the list of faces in
7877 the `face' property (either the character's text property or an
7878 overlay property).
7879
7880 This means that you no longer need to create named faces to use
7881 arbitrary colors in a Lisp package.
7882
7883 ** Changes in file-handling functions
7884
7885 *** File-access primitive functions no longer discard an extra redundant
7886 directory name from the beginning of the file name. In other words,
7887 they no longer do anything special with // or /~. That conversion
7888 is now done only in substitute-in-file-name.
7889
7890 This makes it possible for a Lisp program to open a file whose name
7891 begins with ~.
7892
7893 *** If copy-file is unable to set the date of the output file,
7894 it now signals an error with the condition file-date-error.
7895
7896 *** The inode number returned by file-attributes may be an integer (if
7897 the number fits in a Lisp integer) or a list of integers.
7898
7899 *** insert-file-contents can now read from a special file,
7900 as long as the arguments VISIT and REPLACE are nil.
7901
7902 *** The RAWFILE arg to find-file-noselect, if non-nil, now suppresses
7903 character code conversion as well as other things.
7904
7905 Meanwhile, this feature does work with remote file names
7906 (formerly it did not).
7907
7908 *** Lisp packages which create temporary files should use the TMPDIR
7909 environment variable to decide which directory to put them in.
7910
7911 *** interpreter-mode-alist elements now specify regexps
7912 instead of constant strings.
7913
7914 *** expand-file-name no longer treats `//' or `/~' specially. It used
7915 to delete all the text of a file name up through the first slash of
7916 any `//' or `/~' sequence. Now it passes them straight through.
7917
7918 substitute-in-file-name continues to treat those sequences specially,
7919 in the same way as before.
7920
7921 *** The variable `format-alist' is more general now.
7922 The FROM-FN and TO-FN in a format definition can now be strings
7923 which specify shell commands to use as filters to perform conversion.
7924
7925 *** The new function access-file tries to open a file, and signals an
7926 error if that fails. If the open succeeds, access-file does nothing
7927 else, and returns nil.
7928
7929 *** The function insert-directory now signals an error if the specified
7930 directory cannot be listed.
7931
7932 ** Changes in minibuffer input
7933
7934 *** The functions read-buffer, read-variable, read-command, read-string
7935 read-file-name, read-from-minibuffer and completing-read now take an
7936 additional argument which specifies the default value. If this
7937 argument is non-nil, it should be a string; that string is used in two
7938 ways:
7939
7940 It is returned if the user enters empty input.
7941 It is available through the history command M-n.
7942
7943 *** The functions read-string, read-from-minibuffer,
7944 read-no-blanks-input and completing-read now take an additional
7945 argument INHERIT-INPUT-METHOD. If this is non-nil, then the
7946 minibuffer inherits the current input method and the setting of
7947 enable-multibyte-characters from the previously current buffer.
7948
7949 In an interactive spec, you can use M instead of s to read an
7950 argument in this way.
7951
7952 *** All minibuffer input functions discard text properties
7953 from the text you enter in the minibuffer, unless the variable
7954 minibuffer-allow-text-properties is non-nil.
7955
7956 ** Echo area features
7957
7958 *** Clearing the echo area now runs the normal hook
7959 echo-area-clear-hook. Note that the echo area can be used while the
7960 minibuffer is active; in that case, the minibuffer is still active
7961 after the echo area is cleared.
7962
7963 *** The function current-message returns the message currently displayed
7964 in the echo area, or nil if there is none.
7965
7966 ** Keyboard input features
7967
7968 *** tty-erase-char is a new variable that reports which character was
7969 set up as the terminal's erase character when time Emacs was started.
7970
7971 *** num-nonmacro-input-events is the total number of input events
7972 received so far from the terminal. It does not count those generated
7973 by keyboard macros.
7974
7975 ** Frame-related changes
7976
7977 *** make-frame runs the normal hook before-make-frame-hook just before
7978 creating a frame, and just after creating a frame it runs the abnormal
7979 hook after-make-frame-functions with the new frame as arg.
7980
7981 *** The new hook window-configuration-change-hook is now run every time
7982 the window configuration has changed. The frame whose configuration
7983 has changed is the selected frame when the hook is run.
7984
7985 *** Each frame now independently records the order for recently
7986 selected buffers, in its buffer-list frame parameter, so that the
7987 value of other-buffer is now based on the buffers recently displayed
7988 in the selected frame.
7989
7990 *** The value of the frame parameter vertical-scroll-bars
7991 is now `left', `right' or nil. A non-nil value specifies
7992 which side of the window to put the scroll bars on.
7993
7994 ** X Windows features
7995
7996 *** You can examine X resources for other applications by binding
7997 x-resource-class around a call to x-get-resource. The usual value of
7998 x-resource-class is "Emacs", which is the correct value for Emacs.
7999
8000 *** In menus, checkboxes and radio buttons now actually work.
8001 The menu displays the current status of the box or button.
8002
8003 *** The function x-list-fonts now takes an optional fourth argument
8004 MAXIMUM which sets a limit on how many matching fonts to return.
8005 A smaller value of MAXIMUM makes the function faster.
8006
8007 If the only question is whether *any* font matches the pattern,
8008 it is good to supply 1 for this argument.
8009
8010 ** Subprocess features
8011
8012 *** A reminder: it is no longer necessary for subprocess filter
8013 functions and sentinels to do save-match-data, because Emacs does this
8014 automatically.
8015
8016 *** The new function shell-command-to-string executes a shell command
8017 and returns the output from the command as a string.
8018
8019 *** The new function process-contact returns t for a child process,
8020 and (HOSTNAME SERVICE) for a net connection.
8021
8022 ** An error in running pre-command-hook or post-command-hook
8023 does clear the variable to nil. The documentation was wrong before.
8024
8025 ** In define-key-after, if AFTER is t, the new binding now always goes
8026 at the end of the keymap. If the keymap is a menu, this means it
8027 goes after the other menu items.
8028
8029 ** If you have a program that makes several changes in the same area
8030 of the buffer, you can use the macro combine-after-change-calls
8031 around that Lisp code to make it faster when after-change hooks
8032 are in use.
8033
8034 The macro arranges to call the after-change functions just once for a
8035 series of several changes--if that seems safe.
8036
8037 Don't alter the variables after-change-functions and
8038 after-change-function within the body of a combine-after-change-calls
8039 form.
8040
8041 ** If you define an abbrev (with define-abbrev) whose EXPANSION
8042 is not a string, then the abbrev does not expand in the usual sense,
8043 but its hook is still run.
8044
8045 ** Normally, the Lisp debugger is not used (even if you have enabled it)
8046 for errors that are handled by condition-case.
8047
8048 If you set debug-on-signal to a non-nil value, then the debugger is called
8049 regardless of whether there is a handler for the condition. This is
8050 useful for debugging problems that happen inside of a condition-case.
8051
8052 This mode of operation seems to be unreliable in other ways. Errors that
8053 are normal and ought to be handled, perhaps in timers or process
8054 filters, will instead invoke the debugger. So don't say you weren't
8055 warned.
8056
8057 ** The new variable ring-bell-function lets you specify your own
8058 way for Emacs to "ring the bell".
8059
8060 ** If run-at-time's TIME argument is t, the action is repeated at
8061 integral multiples of REPEAT from the epoch; this is useful for
8062 functions like display-time.
8063
8064 ** You can use the function locate-library to find the precise file
8065 name of a Lisp library. This isn't new, but wasn't documented before.
8066
8067 ** Commands for entering view mode have new optional arguments that
8068 can be used from Lisp. Low-level entrance to and exit from view mode
8069 is done by functions view-mode-enter and view-mode-exit.
8070
8071 ** batch-byte-compile-file now makes Emacs return a nonzero status code
8072 if there is an error in compilation.
8073
8074 ** pop-to-buffer, switch-to-buffer-other-window and
8075 switch-to-buffer-other-frame now accept an additional optional
8076 argument NORECORD, much like switch-to-buffer. If it is non-nil,
8077 they don't put the buffer at the front of the buffer list.
8078
8079 ** If your .emacs file leaves the *scratch* buffer non-empty,
8080 Emacs does not display the startup message, so as to avoid changing
8081 the *scratch* buffer.
8082
8083 ** The new function regexp-opt returns an efficient regexp to match a string.
8084 The arguments are STRINGS and (optionally) PAREN. This function can be used
8085 where regexp matching or searching is intensively used and speed is important,
8086 e.g., in Font Lock mode.
8087
8088 ** The variable buffer-display-count is local to each buffer,
8089 and is incremented each time the buffer is displayed in a window.
8090 It starts at 0 when the buffer is created.
8091
8092 ** The new function compose-mail starts composing a mail message
8093 using the user's chosen mail composition agent (specified with the
8094 variable mail-user-agent). It has variants compose-mail-other-window
8095 and compose-mail-other-frame.
8096
8097 ** The `user-full-name' function now takes an optional parameter which
8098 can either be a number (the UID) or a string (the login name). The
8099 full name of the specified user will be returned.
8100
8101 ** Lisp packages that load files of customizations, or any other sort
8102 of user profile, should obey the variable init-file-user in deciding
8103 where to find it. They should load the profile of the user name found
8104 in that variable. If init-file-user is nil, meaning that the -q
8105 option was used, then Lisp packages should not load the customization
8106 files at all.
8107
8108 ** format-time-string now allows you to specify the field width
8109 and type of padding. This works as in printf: you write the field
8110 width as digits in the middle of a %-construct. If you start
8111 the field width with 0, it means to pad with zeros.
8112
8113 For example, %S normally specifies the number of seconds since the
8114 minute; %03S means to pad this with zeros to 3 positions, %_3S to pad
8115 with spaces to 3 positions. Plain %3S pads with zeros, because that
8116 is how %S normally pads to two positions.
8117
8118 ** thing-at-point now supports a new kind of "thing": url.
8119
8120 ** imenu.el changes.
8121
8122 You can now specify a function to be run when selecting an
8123 item from menu created by imenu.
8124
8125 An example of using this feature: if we define imenu items for the
8126 #include directives in a C file, we can open the included file when we
8127 select one of those items.
8128 \f
8129 * Emacs 19.34 is a bug-fix release with no user-visible changes.
8130 \f
8131 * Changes in Emacs 19.33.
8132
8133 ** Bibtex mode no longer turns on Auto Fill automatically. (No major
8134 mode should do that--it is the user's choice.)
8135
8136 ** The variable normal-auto-fill-function specifies the function to
8137 use for auto-fill-function, if and when Auto Fill is turned on.
8138 Major modes can set this locally to alter how Auto Fill works.
8139 \f
8140 * Editing Changes in Emacs 19.32
8141
8142 ** C-x f with no argument now signals an error.
8143 To set the fill column at the current column, use C-u C-x f.
8144
8145 ** Expanding dynamic abbrevs with M-/ is now smarter about case
8146 conversion. If you type the abbreviation with mixed case, and it
8147 matches the beginning of the expansion including case, then the
8148 expansion is copied verbatim. Using SPC M-/ to copy an additional
8149 word always copies it verbatim except when the previous copied word is
8150 all caps.
8151
8152 ** On a non-windowing terminal, which can display only one Emacs frame
8153 at a time, creating a new frame with C-x 5 2 also selects that frame.
8154
8155 When using a display that can show multiple frames at once, C-x 5 2
8156 does make the frame visible, but does not select it. This is the same
8157 as in previous Emacs versions.
8158
8159 ** You can use C-x 5 2 to create multiple frames on MSDOS, just as on a
8160 non-X terminal on Unix. Of course, only one frame is visible at any
8161 time, since your terminal doesn't have the ability to display multiple
8162 frames.
8163
8164 ** On Windows, set win32-pass-alt-to-system to a non-nil value
8165 if you would like tapping the Alt key to invoke the Windows menu.
8166 This feature is not enabled by default; since the Alt key is also the
8167 Meta key, it is too easy and painful to activate this feature by
8168 accident.
8169
8170 ** The command apply-macro-to-region-lines repeats the last defined
8171 keyboard macro once for each complete line within the current region.
8172 It does this line by line, by moving point to the beginning of that
8173 line and then executing the macro.
8174
8175 This command is not new, but was never documented before.
8176
8177 ** You can now use Mouse-1 to place the region around a string constant
8178 (something surrounded by doublequote characters or other delimiter
8179 characters of like syntax) by double-clicking on one of the delimiting
8180 characters.
8181
8182 ** Font Lock mode
8183
8184 *** Font Lock support modes
8185
8186 Font Lock can be configured to use Fast Lock mode and Lazy Lock mode (see
8187 below) in a flexible way. Rather than adding the appropriate function to the
8188 hook font-lock-mode-hook, you can use the new variable font-lock-support-mode
8189 to control which modes have Fast Lock mode or Lazy Lock mode turned on when
8190 Font Lock mode is enabled.
8191
8192 For example, to use Fast Lock mode when Font Lock mode is turned on, put:
8193
8194 (setq font-lock-support-mode 'fast-lock-mode)
8195
8196 in your ~/.emacs.
8197
8198 *** lazy-lock
8199
8200 The lazy-lock package speeds up Font Lock mode by making fontification occur
8201 only when necessary, such as when a previously unfontified part of the buffer
8202 becomes visible in a window. When you create a buffer with Font Lock mode and
8203 Lazy Lock mode turned on, the buffer is not fontified. When certain events
8204 occur (such as scrolling), Lazy Lock makes sure that the visible parts of the
8205 buffer are fontified. Lazy Lock also defers on-the-fly fontification until
8206 Emacs has been idle for a given amount of time.
8207
8208 To use this package, put in your ~/.emacs:
8209
8210 (setq font-lock-support-mode 'lazy-lock-mode)
8211
8212 To control the package behaviour, see the documentation for `lazy-lock-mode'.
8213
8214 ** Changes in BibTeX mode.
8215
8216 *** For all entries allow spaces and tabs between opening brace or
8217 paren and key.
8218
8219 *** Non-escaped double-quoted characters (as in `Sch"of') are now
8220 supported.
8221
8222 ** Gnus changes.
8223
8224 Gnus, the Emacs news reader, has undergone further rewriting. Many new
8225 commands and variables have been added. There should be no
8226 significant incompatibilities between this Gnus version and the
8227 previously released version, except in the message composition area.
8228
8229 Below is a list of the more user-visible changes. Coding changes
8230 between Gnus 5.1 and 5.2 are more extensive.
8231
8232 *** A new message composition mode is used. All old customization
8233 variables for mail-mode, rnews-reply-mode and gnus-msg are now
8234 obsolete.
8235
8236 *** Gnus is now able to generate "sparse" threads -- threads where
8237 missing articles are represented by empty nodes.
8238
8239 (setq gnus-build-sparse-threads 'some)
8240
8241 *** Outgoing articles are stored on a special archive server.
8242
8243 To disable this: (setq gnus-message-archive-group nil)
8244
8245 *** Partial thread regeneration now happens when articles are
8246 referred.
8247
8248 *** Gnus can make use of GroupLens predictions:
8249
8250 (setq gnus-use-grouplens t)
8251
8252 *** A trn-line tree buffer can be displayed.
8253
8254 (setq gnus-use-trees t)
8255
8256 *** An nn-like pick-and-read minor mode is available for the summary
8257 buffers.
8258
8259 (add-hook 'gnus-summary-mode-hook 'gnus-pick-mode)
8260
8261 *** In binary groups you can use a special binary minor mode:
8262
8263 `M-x gnus-binary-mode'
8264
8265 *** Groups can be grouped in a folding topic hierarchy.
8266
8267 (add-hook 'gnus-group-mode-hook 'gnus-topic-mode)
8268
8269 *** Gnus can re-send and bounce mail.
8270
8271 Use the `S D r' and `S D b'.
8272
8273 *** Groups can now have a score, and bubbling based on entry frequency
8274 is possible.
8275
8276 (add-hook 'gnus-summary-exit-hook 'gnus-summary-bubble-group)
8277
8278 *** Groups can be process-marked, and commands can be performed on
8279 groups of groups.
8280
8281 *** Caching is possible in virtual groups.
8282
8283 *** nndoc now understands all kinds of digests, mail boxes, rnews news
8284 batches, ClariNet briefs collections, and just about everything else.
8285
8286 *** Gnus has a new backend (nnsoup) to create/read SOUP packets.
8287
8288 *** The Gnus cache is much faster.
8289
8290 *** Groups can be sorted according to many criteria.
8291
8292 For instance: (setq gnus-group-sort-function 'gnus-group-sort-by-rank)
8293
8294 *** New group parameters have been introduced to set list-address and
8295 expiration times.
8296
8297 *** All formatting specs allow specifying faces to be used.
8298
8299 *** There are several more commands for setting/removing/acting on
8300 process marked articles on the `M P' submap.
8301
8302 *** The summary buffer can be limited to show parts of the available
8303 articles based on a wide range of criteria. These commands have been
8304 bound to keys on the `/' submap.
8305
8306 *** Articles can be made persistent -- as an alternative to saving
8307 articles with the `*' command.
8308
8309 *** All functions for hiding article elements are now toggles.
8310
8311 *** Article headers can be buttonized.
8312
8313 (add-hook 'gnus-article-display-hook 'gnus-article-add-buttons-to-head)
8314
8315 *** All mail backends support fetching articles by Message-ID.
8316
8317 *** Duplicate mail can now be treated properly. See the
8318 `nnmail-treat-duplicates' variable.
8319
8320 *** All summary mode commands are available directly from the article
8321 buffer.
8322
8323 *** Frames can be part of `gnus-buffer-configuration'.
8324
8325 *** Mail can be re-scanned by a daemonic process.
8326
8327 *** Gnus can make use of NoCeM files to filter spam.
8328
8329 (setq gnus-use-nocem t)
8330
8331 *** Groups can be made permanently visible.
8332
8333 (setq gnus-permanently-visible-groups "^nnml:")
8334
8335 *** Many new hooks have been introduced to make customizing easier.
8336
8337 *** Gnus respects the Mail-Copies-To header.
8338
8339 *** Threads can be gathered by looking at the References header.
8340
8341 (setq gnus-summary-thread-gathering-function
8342 'gnus-gather-threads-by-references)
8343
8344 *** Read articles can be stored in a special backlog buffer to avoid
8345 refetching.
8346
8347 (setq gnus-keep-backlog 50)
8348
8349 *** A clean copy of the current article is always stored in a separate
8350 buffer to allow easier treatment.
8351
8352 *** Gnus can suggest where to save articles. See `gnus-split-methods'.
8353
8354 *** Gnus doesn't have to do as much prompting when saving.
8355
8356 (setq gnus-prompt-before-saving t)
8357
8358 *** gnus-uu can view decoded files asynchronously while fetching
8359 articles.
8360
8361 (setq gnus-uu-grabbed-file-functions 'gnus-uu-grab-view)
8362
8363 *** Filling in the article buffer now works properly on cited text.
8364
8365 *** Hiding cited text adds buttons to toggle hiding, and how much
8366 cited text to hide is now customizable.
8367
8368 (setq gnus-cited-lines-visible 2)
8369
8370 *** Boring headers can be hidden.
8371
8372 (add-hook 'gnus-article-display-hook 'gnus-article-hide-boring-headers)
8373
8374 *** Default scoring values can now be set from the menu bar.
8375
8376 *** Further syntax checking of outgoing articles have been added.
8377
8378 The Gnus manual has been expanded. It explains all these new features
8379 in greater detail.
8380 \f
8381 * Lisp Changes in Emacs 19.32
8382
8383 ** The function set-visited-file-name now accepts an optional
8384 second argument NO-QUERY. If it is non-nil, then the user is not
8385 asked for confirmation in the case where the specified file already
8386 exists.
8387
8388 ** The variable print-length applies to printing vectors and bitvectors,
8389 as well as lists.
8390
8391 ** The new function keymap-parent returns the parent keymap
8392 of a given keymap.
8393
8394 ** The new function set-keymap-parent specifies a new parent for a
8395 given keymap. The arguments are KEYMAP and PARENT. PARENT must be a
8396 keymap or nil.
8397
8398 ** Sometimes menu keymaps use a command name, a symbol, which is really
8399 an automatically generated alias for some other command, the "real"
8400 name. In such a case, you should give that alias symbol a non-nil
8401 menu-alias property. That property tells the menu system to look for
8402 equivalent keys for the real name instead of equivalent keys for the
8403 alias.
8404 \f
8405 * Editing Changes in Emacs 19.31
8406
8407 ** Freedom of the press restricted in the United States.
8408
8409 Emacs has been censored in accord with the Communications Decency Act.
8410 This includes removing some features of the doctor program. That law
8411 was described by its supporters as a ban on pornography, but it bans
8412 far more than that. The Emacs distribution has never contained any
8413 pornography, but parts of it were nonetheless prohibited.
8414
8415 For information on US government censorship of the Internet, and what
8416 you can do to bring back freedom of the press, see the web site
8417 `http://www.vtw.org/'.
8418
8419 ** A note about C mode indentation customization.
8420
8421 The old (Emacs 19.29) ways of specifying a C indentation style
8422 do not normally work in the new implementation of C mode.
8423 It has its own methods of customizing indentation, which are
8424 much more powerful than the old C mode. See the Editing Programs
8425 chapter of the manual for details.
8426
8427 However, you can load the library cc-compat to make the old
8428 customization variables take effect.
8429
8430 ** Marking with the mouse.
8431
8432 When you mark a region with the mouse, the region now remains
8433 highlighted until the next input event, regardless of whether you are
8434 using M-x transient-mark-mode.
8435
8436 ** Improved Windows NT/95 support.
8437
8438 *** Emacs now supports scroll bars on Windows NT and Windows 95.
8439
8440 *** Emacs now supports subprocesses on Windows 95. (Subprocesses used
8441 to work on NT only and not on 95.)
8442
8443 *** There are difficulties with subprocesses, though, due to problems
8444 in Windows, beyond the control of Emacs. They work fine as long as
8445 you run Windows applications. The problems arise when you run a DOS
8446 application in a subprocesses. Since current shells run as DOS
8447 applications, these problems are significant.
8448
8449 If you run a DOS application in a subprocess, then the application is
8450 likely to busy-wait, which means that your machine will be 100% busy.
8451 However, if you don't mind the temporary heavy load, the subprocess
8452 will work OK as long as you tell it to terminate before you start any
8453 other DOS application as a subprocess.
8454
8455 Emacs is unable to terminate or interrupt a DOS subprocess.
8456 You have to do this by providing input directly to the subprocess.
8457
8458 If you run two DOS applications at the same time in two separate
8459 subprocesses, even if one of them is asynchronous, you will probably
8460 have to reboot your machine--until then, it will remain 100% busy.
8461 Windows simply does not cope when one Windows process tries to run two
8462 separate DOS subprocesses. Typing CTL-ALT-DEL and then choosing
8463 Shutdown seems to work although it may take a few minutes.
8464
8465 ** M-x resize-minibuffer-mode.
8466
8467 This command, not previously mentioned in NEWS, toggles a mode in
8468 which the minibuffer window expands to show as many lines as the
8469 minibuffer contains.
8470
8471 ** `title' frame parameter and resource.
8472
8473 The `title' X resource now specifies just the frame title, nothing else.
8474 It does not affect the name used for looking up other X resources.
8475 It works by setting the new `title' frame parameter, which likewise
8476 affects just the displayed title of the frame.
8477
8478 The `name' parameter continues to do what it used to do:
8479 it specifies the frame name for looking up X resources,
8480 and also serves as the default for the displayed title
8481 when the `title' parameter is unspecified or nil.
8482
8483 ** Emacs now uses the X toolkit by default, if you have a new
8484 enough version of X installed (X11R5 or newer).
8485
8486 ** When you compile Emacs with the Motif widget set, Motif handles the
8487 F10 key by activating the menu bar. To avoid confusion, the usual
8488 Emacs binding of F10 is replaced with a no-op when using Motif.
8489
8490 If you want to be able to use F10 in Emacs, you can rebind the Motif
8491 menubar to some other key which you don't use. To do so, add
8492 something like this to your X resources file. This example rebinds
8493 the Motif menu bar activation key to S-F12:
8494
8495 Emacs*defaultVirtualBindings: osfMenuBar : Shift<Key>F12
8496
8497 ** In overwrite mode, DEL now inserts spaces in most cases
8498 to replace the characters it "deletes".
8499
8500 ** The Rmail summary now shows the number of lines in each message.
8501
8502 ** Rmail has a new command M-x unforward-rmail-message, which extracts
8503 a forwarded message from the message that forwarded it. To use it,
8504 select a message which contains a forwarded message and then type the command.
8505 It inserts the forwarded message as a separate Rmail message
8506 immediately after the selected one.
8507
8508 This command also undoes the textual modifications that are standardly
8509 made, as part of forwarding, by Rmail and other mail reader programs.
8510
8511 ** Turning off saving of .saves-... files in your home directory.
8512
8513 Each Emacs session writes a file named .saves-... in your home
8514 directory to record which files M-x recover-session should recover.
8515 If you exit Emacs normally with C-x C-c, it deletes that file. If
8516 Emacs or the operating system crashes, the file remains for M-x
8517 recover-session.
8518
8519 You can turn off the writing of these files by setting
8520 auto-save-list-file-name to nil. If you do this, M-x recover-session
8521 will not work.
8522
8523 Some previous Emacs versions failed to delete these files even on
8524 normal exit. This is fixed now. If you are thinking of turning off
8525 this feature because of past experiences with versions that had this
8526 bug, it would make sense to check whether you still want to do so
8527 now that the bug is fixed.
8528
8529 ** Changes to Version Control (VC)
8530
8531 There is a new variable, vc-follow-symlinks. It indicates what to do
8532 when you visit a link to a file that is under version control.
8533 Editing the file through the link bypasses the version control system,
8534 which is dangerous and probably not what you want.
8535
8536 If this variable is t, VC follows the link and visits the real file,
8537 telling you about it in the echo area. If it is `ask' (the default),
8538 VC asks for confirmation whether it should follow the link. If nil,
8539 the link is visited and a warning displayed.
8540
8541 ** iso-acc.el now lets you specify a choice of language.
8542 Languages include "latin-1" (the default) and "latin-2" (which
8543 is designed for entering ISO Latin-2 characters).
8544
8545 There are also choices for specific human languages such as French and
8546 Portuguese. These are subsets of Latin-1, which differ in that they
8547 enable only the accent characters needed for particular language.
8548 The other accent characters, not needed for the chosen language,
8549 remain normal.
8550
8551 ** Posting articles and sending mail now has M-TAB completion on various
8552 header fields (Newsgroups, To, CC, ...).
8553
8554 Completion in the Newsgroups header depends on the list of groups
8555 known to your news reader. Completion in the Followup-To header
8556 offers those groups which are in the Newsgroups header, since
8557 Followup-To usually just holds one of those.
8558
8559 Completion in fields that hold mail addresses works based on the list
8560 of local users plus your aliases. Additionally, if your site provides
8561 a mail directory or a specific host to use for any unrecognized user
8562 name, you can arrange to query that host for completion also. (See the
8563 documentation of variables `mail-directory-process' and
8564 `mail-directory-stream'.)
8565
8566 ** A greatly extended sgml-mode offers new features such as (to be configured)
8567 skeletons with completing read for tags and attributes, typing named
8568 characters including optionally all 8bit characters, making tags invisible
8569 with optional alternate display text, skipping and deleting tag(pair)s.
8570
8571 Note: since Emacs' syntax feature cannot limit the special meaning of ', " and
8572 - to inside <>, for some texts the result, especially of font locking, may be
8573 wrong (see `sgml-specials' if you get wrong results).
8574
8575 The derived html-mode configures this with tags and attributes more or
8576 less HTML3ish. It also offers optional quick keys like C-c 1 for
8577 headline or C-c u for unordered list (see `html-quick-keys'). Edit /
8578 Text Properties / Face or M-g combinations create tags as applicable.
8579 Outline minor mode is supported and level 1 font-locking tries to
8580 fontify tag contents (which only works when they fit on one line, due
8581 to a limitation in font-lock).
8582
8583 External viewing via browse-url can occur automatically upon saving.
8584
8585 ** M-x imenu-add-to-menubar now adds to the menu bar for the current
8586 buffer only. If you want to put an Imenu item in the menu bar for all
8587 buffers that use a particular major mode, use the mode hook, as in
8588 this example:
8589
8590 (add-hook 'emacs-lisp-mode-hook
8591 '(lambda () (imenu-add-to-menubar "Index")))
8592
8593 ** Changes in BibTeX mode.
8594
8595 *** Field names may now contain digits, hyphens, and underscores.
8596
8597 *** Font Lock mode is now supported.
8598
8599 *** bibtex-make-optional-field is no longer interactive.
8600
8601 *** If bibtex-maintain-sorted-entries is non-nil, inserting new
8602 entries is now done with a faster algorithm. However, inserting
8603 will fail in this case if the buffer contains invalid entries or
8604 isn't in sorted order, so you should finish each entry with C-c C-c
8605 (bibtex-close-entry) after you have inserted or modified it.
8606 The default value of bibtex-maintain-sorted-entries is nil.
8607
8608 *** Function `show-all' is no longer bound to a key, since C-u C-c C-q
8609 does the same job.
8610
8611 *** Entries with quotes inside quote-delimited fields (as `author =
8612 "Stefan Sch{\"o}f"') are now supported.
8613
8614 *** Case in field names doesn't matter anymore when searching for help
8615 text.
8616
8617 ** Font Lock mode
8618
8619 *** Global Font Lock mode
8620
8621 Font Lock mode can be turned on globally, in buffers that support it, by the
8622 new command global-font-lock-mode. You can use the new variable
8623 font-lock-global-modes to control which modes have Font Lock mode automagically
8624 turned on. By default, this variable is set so that Font Lock mode is turned
8625 on globally where the buffer mode supports it.
8626
8627 For example, to automagically turn on Font Lock mode where supported, put:
8628
8629 (global-font-lock-mode t)
8630
8631 in your ~/.emacs.
8632
8633 *** Local Refontification
8634
8635 In Font Lock mode, editing a line automatically refontifies that line only.
8636 However, if your change alters the syntactic context for following lines,
8637 those lines remain incorrectly fontified. To refontify them, use the new
8638 command M-g M-g (font-lock-fontify-block).
8639
8640 In certain major modes, M-g M-g refontifies the entire current function.
8641 (The variable font-lock-mark-block-function controls how to find the
8642 current function.) In other major modes, M-g M-g refontifies 16 lines
8643 above and below point.
8644
8645 With a prefix argument N, M-g M-g refontifies N lines above and below point.
8646
8647 ** Follow mode
8648
8649 Follow mode is a new minor mode combining windows showing the same
8650 buffer into one tall "virtual window". The windows are typically two
8651 side-by-side windows. Follow mode makes them scroll together as if
8652 they were a unit. To use it, go to a frame with just one window,
8653 split it into two side-by-side windows using C-x 3, and then type M-x
8654 follow-mode.
8655
8656 M-x follow-mode turns off Follow mode if it is already enabled.
8657
8658 To display two side-by-side windows and activate Follow mode, use the
8659 command M-x follow-delete-other-windows-and-split.
8660
8661 ** hide-show changes.
8662
8663 The hooks hs-hide-hooks and hs-show-hooks have been renamed
8664 to hs-hide-hook and hs-show-hook, to follow the convention for
8665 normal hooks.
8666
8667 ** Simula mode now has a menu containing the most important commands.
8668 The new command simula-indent-exp is bound to C-M-q.
8669
8670 ** etags can now handle programs written in Erlang. Files are
8671 recognised by the extensions .erl and .hrl. The tagged lines are
8672 those that begin a function, record, or macro.
8673
8674 ** MSDOS Changes
8675
8676 *** It is now possible to compile Emacs with the version 2 of DJGPP.
8677 Compilation with DJGPP version 1 also still works.
8678
8679 *** The documentation of DOS-specific aspects of Emacs was rewritten
8680 and expanded; see the ``MS-DOS'' node in the on-line docs.
8681
8682 *** Emacs now uses ~ for backup file names, not .bak.
8683
8684 *** You can simulate mouse-3 on two-button mice by simultaneously
8685 pressing both mouse buttons.
8686
8687 *** A number of packages and commands which previously failed or had
8688 restricted functionality on MS-DOS, now work. The most important ones
8689 are:
8690
8691 **** Printing (both with `M-x lpr-buffer' and with `ps-print' package)
8692 now works.
8693
8694 **** `Ediff' works (in a single-frame mode).
8695
8696 **** `M-x display-time' can be used on MS-DOS (due to the new
8697 implementation of Emacs timers, see below).
8698
8699 **** `Dired' supports Unix-style shell wildcards.
8700
8701 **** The `c-macro-expand' command now works as on other platforms.
8702
8703 **** `M-x recover-session' works.
8704
8705 **** `M-x list-colors-display' displays all the available colors.
8706
8707 **** The `TPU-EDT' package works.
8708 \f
8709 * Lisp changes in Emacs 19.31.
8710
8711 ** The function using-unix-filesystems on Windows NT and Windows 95
8712 tells Emacs to read and write files assuming that they reside on a
8713 remote Unix filesystem. No CR/LF translation is done on any files in
8714 this case. Invoking using-unix-filesystems with t activates this
8715 behavior, and invoking it with any other value deactivates it.
8716
8717 ** Change in system-type and system-configuration values.
8718
8719 The value of system-type on a Linux-based GNU system is now `lignux',
8720 not `linux'. This means that some programs which use `system-type'
8721 need to be changed. The value of `system-configuration' will also
8722 be different.
8723
8724 It is generally recommended to use `system-configuration' rather
8725 than `system-type'.
8726
8727 See the file LINUX-GNU in this directory for more about this.
8728
8729 ** The functions shell-command and dired-call-process
8730 now run file name handlers for default-directory, if it has them.
8731
8732 ** Undoing the deletion of text now restores the positions of markers
8733 that pointed into or next to the deleted text.
8734
8735 ** Timers created with run-at-time now work internally to Emacs, and
8736 no longer use a separate process. Therefore, they now work more
8737 reliably and can be used for shorter time delays.
8738
8739 The new function run-with-timer is a convenient way to set up a timer
8740 to run a specified amount of time after the present. A call looks
8741 like this:
8742
8743 (run-with-timer SECS REPEAT FUNCTION ARGS...)
8744
8745 SECS says how many seconds should elapse before the timer happens.
8746 It may be an integer or a floating point number. When the timer
8747 becomes ripe, the action is to call FUNCTION with arguments ARGS.
8748
8749 REPEAT gives the interval for repeating the timer (measured in
8750 seconds). It may be an integer or a floating point number. nil or 0
8751 means don't repeat at all--call FUNCTION just once.
8752
8753 *** with-timeout provides an easy way to do something but give
8754 up if too much time passes.
8755
8756 (with-timeout (SECONDS TIMEOUT-FORMS...) BODY...)
8757
8758 This executes BODY, but gives up after SECONDS seconds.
8759 If it gives up, it runs the TIMEOUT-FORMS and returns the value
8760 of the last one of them. Normally it returns the value of the last
8761 form in BODY.
8762
8763 *** You can now arrange to call a function whenever Emacs is idle for
8764 a certain length of time. To do this, call run-with-idle-timer. A
8765 call looks like this:
8766
8767 (run-with-idle-timer SECS REPEAT FUNCTION ARGS...)
8768
8769 SECS says how many seconds of idleness should elapse before the timer
8770 runs. It may be an integer or a floating point number. When the
8771 timer becomes ripe, the action is to call FUNCTION with arguments
8772 ARGS.
8773
8774 Emacs becomes idle whenever it finishes executing a keyboard or mouse
8775 command. It remains idle until it receives another keyboard or mouse
8776 command.
8777
8778 REPEAT, if non-nil, means this timer should be activated again each
8779 time Emacs becomes idle and remains idle for SECS seconds The timer
8780 does not repeat if Emacs *remains* idle; it runs at most once after
8781 each time Emacs becomes idle.
8782
8783 If REPEAT is nil, the timer runs just once, the first time Emacs is
8784 idle for SECS seconds.
8785
8786 *** post-command-idle-hook is now obsolete; you shouldn't use it at
8787 all, because it interferes with the idle timer mechanism. If your
8788 programs use post-command-idle-hook, convert them to use idle timers
8789 instead.
8790
8791 *** y-or-n-p-with-timeout lets you ask a question but give up if
8792 there is no answer within a certain time.
8793
8794 (y-or-n-p-with-timeout PROMPT SECONDS DEFAULT-VALUE)
8795
8796 asks the question PROMPT (just like y-or-n-p). If the user answers
8797 within SECONDS seconds, it returns the answer that the user gave.
8798 Otherwise it gives up after SECONDS seconds, and returns DEFAULT-VALUE.
8799
8800 ** Minor change to `encode-time': you can now pass more than seven
8801 arguments. If you do that, the first six arguments have the usual
8802 meaning, the last argument is interpreted as the time zone, and the
8803 arguments in between are ignored.
8804
8805 This means that it works to use the list returned by `decode-time' as
8806 the list of arguments for `encode-time'.
8807
8808 ** The default value of load-path now includes the directory
8809 /usr/local/share/emacs/VERSION/site-lisp In addition to
8810 /usr/local/share/emacs/site-lisp. You can use this new directory for
8811 site-specific Lisp packages that belong with a particular Emacs
8812 version.
8813
8814 It is not unusual for a Lisp package that works well in one Emacs
8815 version to cause trouble in another. Sometimes packages need updating
8816 for incompatible changes; sometimes they look at internal data that
8817 has changed; sometimes the package has been installed in Emacs itself
8818 and the installed version should be used. Whatever the reason for the
8819 problem, this new feature makes it easier to solve.
8820
8821 ** When your program contains a fixed file name (like .completions or
8822 .abbrev.defs), the file name usually needs to be different on operating
8823 systems with limited file name syntax.
8824
8825 Now you can avoid ad-hoc conditionals by using the function
8826 convert-standard-filename to convert the file name to a proper form
8827 for each operating system. Here is an example of use, from the file
8828 completions.el:
8829
8830 (defvar save-completions-file-name
8831 (convert-standard-filename "~/.completions")
8832 "*The filename to save completions to.")
8833
8834 This sets the variable save-completions-file-name to a value that
8835 depends on the operating system, because the definition of
8836 convert-standard-filename depends on the operating system. On
8837 Unix-like systems, it returns the specified file name unchanged. On
8838 MS-DOS, it adapts the name to fit the limitations of that system.
8839
8840 ** The interactive spec N now returns the numeric prefix argument
8841 rather than the raw prefix argument. (It still reads a number using the
8842 minibuffer if there is no prefix argument at all.)
8843
8844 ** When a process is deleted, this no longer disconnects the process
8845 marker from its buffer position.
8846
8847 ** The variable garbage-collection-messages now controls whether
8848 Emacs displays a message at the beginning and end of garbage collection.
8849 The default is nil, meaning there are no messages.
8850
8851 ** The variable debug-ignored-errors specifies certain kinds of errors
8852 that should not enter the debugger. Its value is a list of error
8853 condition symbols and/or regular expressions. If the error has any
8854 of the condition symbols listed, or if any of the regular expressions
8855 matches the error message, then that error does not enter the debugger,
8856 regardless of the value of debug-on-error.
8857
8858 This variable is initialized to match certain common but uninteresting
8859 errors that happen often during editing.
8860
8861 ** The new function error-message-string converts an error datum
8862 into its error message. The error datum is what condition-case
8863 puts into the variable, to describe the error that happened.
8864
8865 ** Anything that changes which buffer appears in a given window
8866 now runs the window-scroll-functions for that window.
8867
8868 ** The new function get-buffer-window-list returns a list of windows displaying
8869 a buffer. The function is called with the buffer (a buffer object or a buffer
8870 name) and two optional arguments specifying the minibuffer windows and frames
8871 to search. Therefore this function takes optional args like next-window etc.,
8872 and not get-buffer-window.
8873
8874 ** buffer-substring now runs the hook buffer-access-fontify-functions,
8875 calling each function with two arguments--the range of the buffer
8876 being accessed. buffer-substring-no-properties does not call them.
8877
8878 If you use this feature, you should set the variable
8879 buffer-access-fontified-property to a non-nil symbol, which is a
8880 property name. Then, if all the characters in the buffer range have a
8881 non-nil value for that property, the buffer-access-fontify-functions
8882 are not called. When called, these functions should put a non-nil
8883 property on the text that they fontify, so that they won't get called
8884 over and over for the same text.
8885
8886 ** Changes in lisp-mnt.el
8887
8888 *** The lisp-mnt package can now recognize file headers that are written
8889 in the formats used by the `what' command and the RCS `ident' command:
8890
8891 ;; @(#) HEADER: text
8892 ;; $HEADER: text $
8893
8894 in addition to the normal
8895
8896 ;; HEADER: text
8897
8898 *** The commands lm-verify and lm-synopsis are now interactive. lm-verify
8899 checks that the library file has proper sections and headers, and
8900 lm-synopsis extracts first line "synopsis'"information.
8901
8902
8903 \f
8904 * For older news, see the file ONEWS
8905
8906 ----------------------------------------------------------------------
8907 Copyright information:
8908
8909 Copyright (C) 1999, 2000 Free Software Foundation, Inc.
8910
8911 Permission is granted to anyone to make or distribute verbatim copies
8912 of this document as received, in any medium, provided that the
8913 copyright notice and this permission notice are preserved,
8914 thus giving the recipient permission to redistribute in turn.
8915
8916 Permission is granted to distribute modified versions
8917 of this document, or of portions of it,
8918 under the above conditions, provided also that they
8919 carry prominent notices stating who last changed them.
8920 \f
8921 Local variables:
8922 mode: outline
8923 paragraph-separate: "[ \f]*$"
8924 end: