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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 ** `browse-url-gnome-moz' is a new option for
36 `browse-url-browser-function', invoking Mozilla in GNOME.
37
38 +++
39 ** The new global minor mode `auto-image-file-mode' allows image files
40 to be visited as images.
41
42 +++
43 ** The functions `keep-lines', `flush-lines' and `how-many' now
44 operate on the active region in Transient Mark mode.
45
46 ** The header line in an Info buffer is now displayed as an emacs header-line
47 (which is like a mode-line, but at the top of the window), so that it
48 remains visible even when the buffer has been scrolled. This behavior
49 may be disabled by customizing the option `Info-use-header-line'.
50
51 +++
52 ** `gnus-user-agent' is a new possibility for `mail-user-agent'. It
53 is like `message-user-agent', but with all the Gnus paraphernalia.
54
55 +++
56 ** The recommended way of using Iswitchb is via the new global minor
57 mode `iswitchb-mode'.
58
59 +++
60 ** Gnus changes.
61
62 The Gnus NEWS entries are short, but they reflect sweeping changes in
63 four areas: Article display treatment, MIME treatment,
64 internationalization and mail-fetching.
65
66 *** The mail-fetching functions have changed. See the manual for the
67 many details. In particular, all procmail fetching variables are gone.
68
69 If you used procmail like in
70
71 (setq nnmail-use-procmail t)
72 (setq nnmail-spool-file 'procmail)
73 (setq nnmail-procmail-directory "~/mail/incoming/")
74 (setq nnmail-procmail-suffix "\\.in")
75
76 this now has changed to
77
78 (setq mail-sources
79 '((directory :path "~/mail/incoming/"
80 :suffix ".in")))
81
82 More information is available in the info doc at Select Methods ->
83 Getting Mail -> Mail Sources
84
85 *** Gnus is now a MIME-capable reader. This affects many parts of
86 Gnus, and adds a slew of new commands. See the manual for details.
87
88 *** Gnus has also been multilingualized. This also affects too many
89 parts of Gnus to summarize here, and adds many new variables.
90 Separate MIME packages like SEMI will not work. There are built-in
91 facilities equivalent to those of gnus-mule.el, which is now just a
92 compatibility layer.
93
94 *** gnus-auto-select-first can now be a function to be
95 called to position point.
96
97 *** The user can now decide which extra headers should be included in
98 summary buffers and NOV files.
99
100 *** `gnus-article-display-hook' has been removed. Instead, a number
101 of variables starting with `gnus-treat-' have been added.
102
103 *** The Gnus posting styles have been redone again and now work in a
104 subtly different manner.
105
106 *** New web-based backends have been added: nnslashdot, nnwarchive
107 and nnultimate. nnweb has been revamped, again, to keep up with
108 ever-changing layouts.
109
110 *** Gnus can now read IMAP mail via nnimap.
111
112 *** There is image support.
113
114 ** When your terminal can't display characters from some of the ISO
115 8859 character sets but can display Latin-1, you can display
116 more-or-less mnemonic sequences of ASCII/Latin-1 characters instead of
117 empty boxes (under a window system) or question marks (not under a
118 window system). Customize the option `latin1-display' to turn this
119 on.
120
121 ** The new user-option `find-file-suppress-same-file-warnings' can be
122 set to suppress warnings ``X and Y are the same file'' when visiting a
123 file that is already visited under a different name.
124
125 ** The new user-option `electric-help-shrink-window' can be set to
126 nil to prevent adjusting the help window size to the buffer size.
127
128 ** Emacs now checks for recursive loads of Lisp files. If the
129 recursion depth exceeds `recursive-load-depth-limit', an error is
130 signaled.
131
132 ** The Strokes package has been updated. If your Emacs has XPM
133 support, you can use it for pictographic editing. In Strokes mode,
134 use C-mouse-2 to compose a complex stoke and insert it into the
135 buffer. You can encode or decode a strokes buffer with new commands
136 M-x strokes-encode-buffer and M-x strokes-decode-buffer. There is a
137 new command M-x strokes-list-strokes.
138
139 +++
140 ** New command M-x describe-character-set reads a character set name
141 and displays information about that.
142
143 ** When an error is signaled during the loading of the user's init
144 file, Emacs now pops up the *Messages* buffer.
145
146 ** Polish and German translations of Emacs' reference card have been
147 added. They are named `pl-refcard.tex' and `de-refcard.tex'.
148 Postscript files are included.
149
150 ** A reference card for Dired has been added. Its name is
151 `dired-ref.tex'.
152
153 ** The new variable `auto-mode-interpreter-regexp' contains a regular
154 expression matching interpreters, for file mode determination.
155
156 This regular expression is matched against the first line of a file to
157 determine the file's mode in `set-auto-mode' when Emacs can't deduce a
158 mode from the file's name. If it matches, the file is assumed to be
159 interpreted by the interpreter matched by the second group of the
160 regular expression. The mode is then determined as the mode
161 associated with that interpreter in `interpreter-mode-alist'.
162
163 +++
164 ** C-down-mouse-3 is bound differently. Now if the menu bar is not
165 displayed it pops up a menu containing the items which would be on the
166 menu bar. If the menu bar is displayed, it pops up the major mode
167 menu or the Edit menu if there is no major mode menu.
168
169 ** Variable `load-path' is no longer customizable because it contains
170 a version-dependent component.
171
172 ** The <delete> function key is now bound to `delete-char' by default.
173 Note that this takes effect only on window systems. On TTYs, Emacs
174 will receive ASCII 127 when the DEL key is pressed. This
175 character is still bound as before.
176
177 ** Item Save Options on the Options menu allows saving options set
178 using that menu.
179
180 ** New function executable-make-buffer-file-executable-if-script-p is
181 suitable as an after-save-hook as an alternative to `executable-chmod'.
182
183 +++
184 ** The most preferred coding-system is now used to save a buffer if
185 buffer-file-coding-system is `undecided' and it is safe for the buffer
186 contents. (The most preferred is set by set-language-environment or
187 by M-x prefer-coding-system.) Thus if you visit an ASCII file and
188 insert a non-ASCII character from your current language environment,
189 the file will be saved silently with the appropriate coding.
190 Previously you would be prompted for a safe coding system.
191
192 +++
193 ** New variable `inhibit-iso-escape-detection' determines if Emacs'
194 coding system detection algorithm should pay attention to ISO2022's
195 escape sequences. If this variable is non-nil, the algorithm ignores
196 such escape sequences. The default value is nil, and it is
197 recommended not to change it except for the special case that you
198 always want to read any escape code verbatim. If you just want to
199 read a specific file without decoding escape codes, use C-x RET c
200 (`universal-coding-system-argument'). For instance, C-x RET c latin-1
201 RET C-x C-f filename RET.
202
203 ** Variable `default-korean-keyboard' is initialized properly from the
204 environment variable `HANGUL_KEYBOARD_TYPE'.
205
206 +++
207 ** C-u C-x = provides detailed information about the character at
208 point in a pop-up window.
209
210 +++
211 ** New command M-x list-charset-chars reads a character set name and
212 displays all characters in that character set.
213
214 ** M-x set-terminal-coding-system (C-x RET t) now allows CCL-based
215 coding systems such as cpXXX and cyrillic-koi8.
216
217 +++
218 ** M-; now calls comment-dwim which tries to do something clever based
219 on the context. M-x kill-comment is now an alias to comment-kill,
220 defined on newcomment.el.
221
222 +++
223 ** The function `getenv' is now callable interactively.
224
225 ** The many obsolete language `setup-...-environment' commands have
226 been removed -- use `set-language-environment'.
227
228 +++
229 ** New user options `display-time-mail-face' and
230 `display-time-use-mail-icon' control the appearance of mode-line mail
231 indicator used by the display-time package. On a suitable display the
232 indicator can be an icon and is mouse-sensitive.
233
234 +++
235 ** Emacs' auto-save list files are now by default stored in a
236 sub-directory `.emacs.d/auto-save-list/' of the user's home directory.
237 (On MS-DOS, this subdirectory's name is `_emacs.d/auto-save.list/'.)
238 You can customize `auto-save-list-prefix' to change this location.
239
240 +++
241 ** On window-systems, additional space can be put between text lines
242 on the display using several methods
243
244 +++
245 - By setting frame parameter `line-spacing' to PIXELS. PIXELS must be
246 a positive integer, and specifies that PIXELS number of pixels should
247 be put below text lines on the affected frame or frames.
248
249 +++
250 - By setting X resource `lineSpacing', class `LineSpacing'. This is
251 equivalent ot specifying the frame parameter.
252
253 - By specifying `--line-spacing=N' or `-lsp N' on the command line.
254
255 - By setting buffer-local variable `line-spacing'. The meaning is
256 the same, but applies to the a particular buffer only.
257
258 +++
259 ** The new command `clone-indirect-buffer' can be used to create
260 an indirect buffer that is a twin copy of the current buffer. The
261 command `clone-indirect-buffer-other-window', bound to C-x 4 c,
262 does the same but displays the indirect buffer in another window.
263
264 +++
265 ** New user options `backup-directory-alist' and
266 `make-backup-file-name-function' control the placement of backups,
267 typically in a single directory or in an invisible sub-directory.
268
269 ** New commands iso-iso2sgml and iso-sgml2iso convert between Latin-1
270 characters and the corresponding SGML (HTML) entities.
271
272 +++
273 ** Emacs now refuses to load compiled Lisp files which weren't
274 compiled with Emacs. Set `load-dangerous-libraries' to t to change
275 this behavior.
276
277 The reason for this change is an incompatible change in XEmacs' byte
278 compiler. Files compiled with XEmacs can contain byte codes that let
279 Emacs dump core.
280
281 +++
282 ** New X resources recognized
283
284 *** The X resource `synchronous', class `Synchronous', specifies
285 whether Emacs should run in synchronous mode. Synchronous mode
286 is useful for debugging X problems.
287
288 Example:
289
290 emacs.synchronous: true
291
292 *** The X resource `visualClass, class `VisualClass', specifies the
293 visual Emacs should use. The resource's value should be a string of
294 the form `CLASS-DEPTH', where CLASS is the name of the visual class,
295 and DEPTH is the requested color depth as a decimal number. Valid
296 visual class names are
297
298 TrueColor
299 PseudoColor
300 DirectColor
301 StaticColor
302 GrayScale
303 StaticGray
304
305 Visual class names specified as X resource are case-insensitive, i.e.
306 `pseudocolor', `Pseudocolor' and `PseudoColor' all have the same
307 meaning.
308
309 The program `xdpyinfo' can be used to list the visual classes
310 supported on your display, and which depths they have. If
311 `visualClass' is not specified, Emacs uses the display's default
312 visual.
313
314 Example:
315
316 emacs.visualClass: TrueColor-8
317
318 *** The X resource `privateColormap', class `PrivateColormap',
319 specifies that Emacs should use a private colormap if it is using the
320 default visual, and that visual is of class PseudoColor. Recognized
321 resource values are `true' or `on'.
322
323 Example:
324
325 emacs.privateColormap: true
326
327 ** The menu bar configuration has changed. The new configuration is
328 more CUA-compliant. The most significant change is that Options is
329 now a separate menu-bar item, with Mule and Customize as its submenus.
330
331 ** User-option `show-cursor-in-non-selected-windows' controls how to
332 display the cursor in non-selected windows. If nil, no cursor is
333 shown, if non-nil a hollow box cursor is shown. This option can
334 be customized.
335
336 +++
337 ** The variable `echo-keystrokes' may now have a floating point value.
338
339 +++
340 ** C-x 5 1 runs the new command delete-other-frames which deletes
341 all frames except the selected one.
342
343 ** If your init file is compiled (.emacs.elc), `user-init-file' is set
344 to the source name (.emacs.el), if that exists, after loading it.
345
346 ** The help string specified for a menu-item whose definition contains
347 the property `:help HELP' is now displayed under X, on MS-Windows, and
348 MS-DOS, either in the echo area or with tooltips. Many standard menus
349 displayed by Emacs now have help strings.
350
351 +++
352 ** Highlighting of mouse-sensitive regions is now supported in the
353 MS-DOS version of Emacs.
354
355 ** New user option `read-mail-command' specifies a command to use to
356 read mail from the menu etc.
357
358 +++
359 ** Hexl contains a new command `hexl-insert-hex-string' which inserts
360 a string of hexadecimal numbers read from the mini-buffer.
361
362 ** Changes in Texinfo mode.
363
364 ** A couple of new key bindings have been added for inserting Texinfo
365 macros
366
367 Key binding Macro
368 -------------------------
369 C-c C-c C-s @strong
370 C-c C-c C-e @emph
371 C-c C-c u @url
372 C-c C-c q @quotation
373 C-c C-c m @email
374
375 ** Changes in Outline mode.
376
377 There is now support for Imenu to index headings. A new command
378 `outline-headers-as-kill' copies the visible headings in the region to
379 the kill ring, e.g. to produce a table of contents.
380
381 ** Changes to Emacs Server
382
383 +++
384 *** The new option `server-kill-new-buffers' specifies what to do
385 with buffers when done with them. If non-nil, the default, buffers
386 are killed, unless they were already present before visiting them with
387 Emacs Server. If nil, `server-temp-file-regexp' specifies which
388 buffers to kill, as before.
389
390 Please note that only buffers are killed that still have a client,
391 i.e. buffers visited with `emacsclient --no-wait' are never killed in
392 this way.
393
394 ** Changes to Show Paren mode.
395
396 *** Overlays used by Show Paren mode now use a priority property.
397 The new user option show-paren-priority specifies the priority to
398 use. Default is 1000.
399
400 +++
401 ** New command M-x check-parens can be used to find unbalanced paren
402 groups and strings in buffers in Lisp mode (or other modes).
403
404 +++
405 ** You can now easily create new *Info* buffers using either
406 M-x clone-buffer, C-u m <entry> RET or C-u g <entry> RET.
407 M-x clone-buffer can also be used on *Help* and several other special
408 buffers.
409
410 +++
411 ** Emacs can now support 'wheeled' mice (such as the MS IntelliMouse)
412 under XFree86. To enable this, simply put (mwheel-install) in your
413 .emacs file.
414
415 The variables `mwheel-follow-mouse' and `mwheel-scroll-amount'
416 determine where and by how much buffers are scrolled.
417
418 ** Listing buffers with M-x list-buffers (C-x C-b) now shows
419 abbreviated file names. Abbreviations can be customized by changing
420 `directory-abbrev-alist'.
421
422 ** Faces and frame parameters.
423
424 There are four new faces `scroll-bar', `border', `cursor' and `mouse'.
425 Setting the frame parameters `scroll-bar-foreground' and
426 `scroll-bar-background' sets foreground and background color of face
427 `scroll-bar' and vice versa. Setting frame parameter `border-color'
428 sets the background color of face `border' and vice versa. Likewise
429 for frame parameters `cursor-color' and face `cursor', and frame
430 parameter `mouse-color' and face `mouse'.
431
432 Changing frame parameter `font' sets font-related attributes of the
433 `default' face and vice versa. Setting frame parameters
434 `foreground-color' or `background-color' sets the colors of the
435 `default' face and vice versa.
436
437 +++
438 ** New face `menu'.
439
440 The face `menu' can be used to change colors and font of Emacs' menus.
441 Setting the font of LessTif/Motif menus is currently not supported;
442 attempts to set the font are ignored in this case.
443
444 +++
445 ** New frame parameter `screen-gamma' for gamma correction.
446
447 The new frame parameter `screen-gamma' specifies gamma-correction for
448 colors. Its value may be nil, the default, in which case no gamma
449 correction occurs, or a number > 0, usually a float, that specifies
450 the screen gamma of a frame's display.
451
452 PC monitors usually have a screen gamma of 2.2. smaller values result
453 in darker colors. You might want to try a screen gamma of 1.5 for LCD
454 color displays. The viewing gamma Emacs uses is 0.4545. (1/2.2).
455
456 The X resource name of this parameter is `screenGamma', class
457 `ScreenGamma'.
458
459 ** Emacs has a new redisplay engine.
460
461 The new redisplay handles characters of variable width and height.
462 Italic text can be used without redisplay problems. Fonts containing
463 oversized characters, i.e. characters larger than the logical height
464 of a font can be used. Images of various formats can be displayed in
465 the text.
466
467 ** Emacs has a new face implementation.
468
469 The new faces no longer fundamentally use X font names to specify the
470 font. Instead, each face has several independent attributes--family,
471 height, width, weight and slant--that it may or may not specify.
472 These attributes can be merged from various faces, and then together
473 specify a font.
474
475 Faces are supported on terminals that can display color or fonts.
476 These terminal capabilities are auto-detected. Details can be found
477 under Lisp changes, below.
478
479 ** New default font is Courier 12pt.
480
481 +++
482 ** When using a windowing terminal, each Emacs window now has a cursor
483 of its own. When the window is selected, the cursor is solid;
484 otherwise, it is hollow.
485
486 ** Bitmap areas to the left and right of windows are used to display
487 truncation marks, continuation marks, overlay arrows and alike. The
488 foreground, background, and stipple of these areas can be changed by
489 customizing face `fringe'.
490
491 ** The mode line under X is now drawn with shadows by default. You
492 can change its appearance by modifying the face `modeline'.
493
494 ** LessTif support.
495
496 Emacs now runs with the LessTif toolkit (see <http://www.lesstif.org>).
497 You will need a version 0.88.1 or later.
498
499 ** Toolkit scroll bars.
500
501 Emacs now uses toolkit scrollbars if available. When configured for
502 LessTif/Motif, it will use that toolkit's scrollbar. Otherwise, when
503 configured for Lucid and Athena widgets, it will use the Xaw3d scroll
504 bar if Xaw3d is available. You can turn off the use of toolkit scroll
505 bars by specifying `--with-toolkit-scroll-bars=no' when configuring
506 Emacs.
507
508 When you encounter problems with the Xaw3d scroll bar, watch out how
509 Xaw3d is compiled on your system. If the Makefile generated from
510 Xaw3d's Imakefile contains a `-DNARROWPROTO' compiler option, and your
511 Emacs system configuration file `s/your-system.h' does not contain a
512 define for NARROWPROTO, you might consider adding it. Take
513 `s/freebsd.h' as an example.
514
515 Alternatively, if you don't have access to the Xaw3d source code, take
516 a look at your system's imake configuration file, for example in the
517 directory `/usr/X11R6/lib/X11/config' (paths are different on
518 different systems). You will find files `*.cf' there. If your
519 system's cf-file contains a line like `#define NeedWidePrototypes NO',
520 add a `#define NARROWPROTO' to your Emacs system configuration file.
521
522 The reason for this is that one Xaw3d function uses `double' or
523 `float' function parameters depending on the setting of NARROWPROTO.
524 This is not a problem when Imakefiles are used because each system's
525 image configuration file contains the necessary information. Since
526 Emacs doesn't use imake, this has do be done manually.
527
528 ** Toggle buttons and radio buttons in menus.
529
530 When compiled with LessTif (or Motif) support, Emacs uses toolkit
531 widgets for radio and toggle buttons in menus. When configured for
532 Lucid, Emacs draws radio buttons and toggle buttons similar to Motif.
533
534 +++
535 ** Highlighting of trailing whitespace.
536
537 When `show-trailing-whitespace' is non-nil, Emacs displays trailing
538 whitespace in the face `trailing-whitespace'. Trailing whitespace is
539 defined as spaces or tabs at the end of a line. To avoid busy
540 highlighting when entering new text, trailing whitespace is not
541 displayed if point is at the end of the line containing the
542 whitespace.
543
544 +++
545 ** Busy-cursor.
546
547 Emacs can optionally display a busy-cursor under X. You can turn the
548 display on or off by customizing group `cursor'.
549
550 +++
551 ** Blinking cursor
552
553 M-x blink-cursor-mode toggles a blinking cursor under X and on
554 terminals having terminal capabilities `vi', `vs', and `ve'. Blinking
555 and related parameters like frequency and delay can be customized in
556 the group `cursor'.
557
558 +++
559 ** New font-lock support mode `jit-lock-mode'.
560
561 This support mode is roughly equivalent to `lazy-lock' but is
562 generally faster. It supports stealth and deferred fontification.
563 See the documentation of the function `jit-lock-mode' for more
564 details.
565
566 Font-lock uses jit-lock-mode as default support mode, so you don't
567 have to do anything to activate it.
568
569 ** Tabs and variable-width text.
570
571 Tabs are now displayed with stretch properties; the width of a tab is
572 defined as a multiple of the normal character width of a frame, and is
573 independent of the fonts used in the text where the tab appears.
574 Thus, tabs can be used to line up text in different fonts.
575
576 ** Enhancements of the Lucid menu bar
577
578 +++
579 *** The Lucid menu bar now supports the resource "margin".
580
581 emacs.pane.menubar.margin: 5
582
583 The default margin is 4 which makes the menu bar appear like the
584 LessTif/Motif one.
585
586 *** Arrows that indicate sub-menus are now drawn with shadows, as in
587 LessTif and Motif.
588
589 +++
590 ** Hscrolling in C code.
591
592 Horizontal scrolling now happens automatically if
593 `automatic-hscrolling' is set (the default). This setting can be
594 customized.
595
596 +++
597 ** Tool bar support.
598
599 Emacs supports a tool bar at the top of a frame under X. For details
600 how to define a tool bar, see the page describing Lisp-level changes.
601 Tool-bar global minor mode controls whether or not it is displayed.
602 To make the tool bar more useful, we need contributions of extra icons
603 for specific modes (with copyright assignments).
604
605 +++
606 ** Mouse-sensitive mode line.
607
608 Different parts of the mode line under X have been made
609 mouse-sensitive. Moving the mouse to a mouse-sensitive part in the mode
610 line changes the appearance of the mouse pointer to an arrow, and help
611 about available mouse actions is displayed either in the echo area, or
612 in the tooltip window if you have enabled one.
613
614 Currently, the following actions have been defined:
615
616 - Mouse-1 on the buffer name in the mode line switches between two
617 buffers.
618
619 - Mouse-2 on the buffer-name switches to the next buffer, and
620 M-mouse-2 switches to the previous buffer in the buffer list.
621
622 - Mouse-3 on the buffer-name displays a buffer menu.
623
624 - Mouse-2 on the read-only or modified status in the mode line (`%' or
625 `*') toggles the status.
626
627 - Mouse-3 on the mode name display a minor-mode menu.
628
629 ** LessTif/Motif file selection dialog.
630
631 When Emacs is configured to use LessTif or Motif, reading a file name
632 from a menu will pop up a file selection dialog if `use-dialog-box' is
633 non-nil.
634
635 ** Emacs can display faces on TTY frames.
636
637 Emacs automatically detects terminals that are able to display colors.
638 Faces with a weight greater than normal are displayed extra-bright, if
639 the terminal supports it. Faces with a weight less than normal and
640 italic faces are displayed dimmed, if the terminal supports it.
641 Underlined faces are displayed underlined if possible. Other face
642 attributes such as `overline', `strike-through', and `box' are ignored
643 on terminals.
644
645 ** Sound support
646
647 Emacs supports playing sound files on GNU/Linux and FreeBSD (Voxware
648 driver and native BSD driver, a.k.a. Luigi's driver). Currently
649 supported file formats are RIFF-WAVE (*.wav) and Sun Audio (*.au).
650
651 +++
652 ** A new variable, backup-by-copying-when-privileged-mismatch, gives
653 the highest file uid for which backup-by-copying-when-mismatch will be
654 forced on. The assumption is that uids less than or equal to this
655 value are special uids (root, bin, daemon, etc.--not real system
656 users) and that files owned by these users should not change ownership,
657 even if your system policy allows users other than root to edit them.
658
659 The default is 200; set the variable to nil to disable the feature.
660
661 +++
662 ** A block cursor can be drawn as wide as the glyph under it under X.
663
664 As an example: if a block cursor is over a tab character, it will be
665 drawn as wide as that tab on the display. To do this, set
666 `x-stretch-cursor' to a non-nil value.
667
668 +++
669 ** Empty display lines at the end of a buffer may be marked with a
670 bitmap (this is similar to the tilde displayed by vi).
671
672 This behavior is activated by setting the buffer-local variable
673 `indicate-empty-lines' to a non-nil value. The default value of this
674 variable is found in `default-indicate-empty-lines'.
675
676 +++
677 ** There is a new "aggressive" scrolling method.
678
679 When scrolling up because point is above the window start, if the
680 value of the buffer-local variable `scroll-up-aggessively' is a
681 number, Emacs chooses a new window start so that point ends up that
682 fraction of the window's height from the top of the window.
683
684 When scrolling down because point is below the window end, if the
685 value of the buffer-local variable `scroll-down-aggessively' is a
686 number, Emacs chooses a new window start so that point ends up that
687 fraction of the window's height from the bottom of the window.
688
689 ** The rectangle commands now avoid inserting undesirable spaces,
690 notably at the end of lines.
691
692 All these functions have been rewritten to avoid inserting unwanted
693 spaces, and an optional prefix now allows them to behave the old way.
694
695 +++
696 There is a new command M-x replace-rectangle.
697
698 ** The new command M-x query-replace-regexp-eval acts like
699 query-replace-regexp, but takes a Lisp expression which is evaluated
700 after each match to get the replacement text.
701
702 +++
703 ** M-x query-replace recognizes a new command `e' (or `E') that lets
704 you edit the replacement string.
705
706 ** The new command mail-abbrev-complete-alias, bound to `M-TAB', lets
707 you complete mail aliases in the text, analogous to
708 lisp-complete-symbol.
709
710 +++
711 ** Emacs now resizes mini-windows if appropriate.
712
713 If a message is longer than one line, or minibuffer contents are
714 longer than one line, Emacs now resizes the minibuffer window unless
715 it is on a frame of its own. You can control the maximum minibuffer
716 window size by setting the following variable:
717
718 - User option: max-mini-window-height
719
720 Maximum height for resizing mini-windows. If a float, it specifies a
721 fraction of the mini-window frame's height. If an integer, it
722 specifies a number of lines. If nil, don't resize.
723
724 Default is 0.25.
725
726 ** The command `Info-search' now uses a search history.
727
728 ** Changes to hideshow.el
729
730 Hideshow is now at version 5.x. It uses a new algorithms for block
731 selection and traversal, includes more isearch support, and has more
732 conventional keybindings.
733
734 *** Generalized block selection and traversal
735
736 A block is now recognized by three things: its start and end regexps
737 (both strings), and a match-data selector (an integer) specifying
738 which sub-expression in the start regexp serves as the place where a
739 `forward-sexp'-like function can operate. Hideshow always adjusts
740 point to this sub-expression before calling `hs-forward-sexp-func'
741 (which for most modes evaluates to `forward-sexp').
742
743 If the match-data selector is not specified, it defaults to zero,
744 i.e., the entire start regexp is valid, w/ no prefix. This is
745 backwards compatible with previous versions of hideshow. Please see
746 the docstring for variable `hs-special-modes-alist' for details.
747
748 *** Isearch support for updating mode line
749
750 During incremental search, if Hideshow minor mode is active, hidden
751 blocks are temporarily shown. The variable `hs-headline' records the
752 line at the beginning of the opened block (preceding the hidden
753 portion of the buffer), and the mode line is refreshed. When a block
754 is re-hidden, the variable is set to nil.
755
756 To show `hs-headline' in the mode line, you may wish to include
757 something like this in your .emacs.
758
759 (add-hook 'hs-minor-mode-hook
760 (lambda ()
761 (add-to-list 'mode-line-format 'hs-headline)))
762
763 *** New customization var: `hs-hide-all-non-comment-function'
764
765 Normally, `hs-hide-all' hides everything, leaving only the
766 header lines of top-level forms (and comments, unless var
767 `hs-hide-comments-when-hiding-all' is non-nil). It does this by
768 moving point to each top-level block beginning and hiding the
769 block there. In some major modes (for example, Java), this
770 behavior results in few blocks left visible, which may not be so
771 useful.
772
773 You can now set var `hs-hide-all-non-comment-function' to a
774 function to be called at each top-level block beginning, instead
775 of the normal block-hiding function. For example, the following
776 code defines a function to hide one level down and move point
777 appropriately, and then tells hideshow to use the new function.
778
779 (defun ttn-hs-hide-level-1 ()
780 (hs-hide-level 1)
781 (forward-sexp 1))
782 (setq hs-hide-all-non-comment-function 'ttn-hs-hide-level-1)
783
784 The name `hs-hide-all-non-comment-function' was chosen to
785 emphasize that this function is not called for comment blocks,
786 only for code blocks.
787
788 *** Command deleted: `hs-show-region'
789
790 Historical Note: This command was added to handle "unbalanced
791 parentheses" emergencies back when hideshow.el used selective
792 display for implementation.
793
794 *** Commands rebound to more conventional keys
795
796 The hideshow commands used to be bound to keys of the form "C-c
797 LETTER". This is contrary to the Emacs keybinding convention,
798 which reserves that space for user modification. Here are the
799 new bindings (which includes the addition of `hs-toggle-hiding'):
800
801 hs-hide-block C-c C-h
802 hs-show-block C-c C-s
803 hs-hide-all C-c C-M-h
804 hs-show-all C-c C-M-s
805 hs-hide-level C-c C-l
806 hs-toggle-hiding C-c C-c
807 hs-mouse-toggle-hiding [(shift button-2)]
808
809 These were chosen to roughly imitate those used by Outline mode.
810
811 ** Changes to Change Log mode and Add-Log functions
812
813 +++
814 *** If you invoke `add-change-log-entry' from a backup file, it makes
815 an entry appropriate for the file's parent. This is useful for making
816 log entries by comparing a version with deleted functions.
817
818 +++
819 **** New command M-x change-log-merge merges another log into the
820 current buffer.
821
822 +++
823 *** New command M-x change-log-redate fixes any old-style date entries
824 in a log file.
825
826 +++
827 *** Change Log mode now adds a file's version number to change log
828 entries if user-option `change-log-version-info-enabled' is non-nil.
829
830 +++
831 *** Unless the file is under version control the search for a file's
832 version number is performed based on regular expressions from
833 `change-log-version-number-regexp-list' which can be cutomized.
834 Version numbers are only found in the first 10 percent of a file.
835
836 *** Change Log mode now defines its own faces for font-lock
837 highlighting.
838
839 ** Changes in Font Lock
840
841 *** The new function `font-lock-remove-keywords' can be used to remove
842 font-lock keywords from the current buffer or from a specific major
843 mode.
844
845 ** Comint (subshell) changes
846
847 By default, comint no longer uses the variable `comint-prompt-regexp' to
848 distinguish prompts from user-input. Instead, it notices which parts of
849 the text were output by the process, and which entered by the user, and
850 attaches `field' properties to allow emacs commands to use this information.
851 Common movement commands, notably beginning-of-line, respect field
852 boundaries in a fairly natural manner.
853 To disable this feature, and use the old behavior, set the variable
854 `comint-use-prompt-regexp-instead-of-fields' to a non-nil value.
855
856 Comint now includes new features to send commands to running processes
857 and redirect the output to a designated buffer or buffers.
858
859 The command M-x comint-redirect-send-command reads a command and
860 buffer name from the mini-buffer. The command is sent to the current
861 buffer's process, and its output is inserted into the specified buffer.
862
863 The command M-x comint-redirect-send-command-to-process acts like
864 M-x comint-redirect-send-command but additionally reads the name of
865 the buffer whose process should be used from the mini-buffer.
866
867 Packages based on comint.el like shell-mode, and scheme-interaction-mode
868 now highlight user input and program prompts, and support choosing
869 previous input with mouse-2. To control these feature, see the
870 user-options `comint-highlight-input' and `comint-highlight-prompt'.
871
872 ** Changes to Rmail mode
873
874 *** The new user-option rmail-rmail-user-mail-address-regexp can be
875 set to fine tune the identification of of the correspondent when
876 receiving new mail. If it matches the address of the sender, the
877 recipient is taken as correspondent of a mail. If nil, the default,
878 `user-login-name' and `user-mail-address' are used to exclude yourself
879 as correspondent.
880
881 Usually you don't have to set this variable, except if you collect
882 mails sent by you under different user names. Then it should be a
883 regexp matching your mail addresses.
884
885 *** The new user-option rmail-confirm-expunge controls whether and how
886 to ask for confirmation before expunging deleted messages from an
887 Rmail file. You can choose between no confirmation, confirmation
888 with y-or-n-p, or confirmation with yes-or-no-p. Default is to ask
889 for confirmation with yes-or-no-p.
890
891 *** RET is now bound in the Rmail summary to rmail-summary-goto-msg,
892 like `j'.
893
894 *** There is a new user option `rmail-digest-end-regexps' that
895 specifies the regular expressions to detect the line that ends a
896 digest message.
897
898 *** The new user option `rmail-automatic-folder-directives' specifies
899 in which folder to put messages automatically.
900
901 ** Changes to TeX mode
902
903 The default mode has been changed from `plain-tex-mode' to
904 `latex-mode'.
905
906 ** Changes to RefTeX mode
907
908 *** RefTeX has new support for index generation. Index entries can be
909 created with `C-c <', with completion available on index keys.
910 Pressing `C-c /' indexes the word at the cursor with a default
911 macro. `C-c >' compiles all index entries into an alphabetically
912 sorted *Index* buffer which looks like the final index. Entries
913 can be edited from that buffer.
914
915 *** Label and citation key selection now allow to select several
916 items and reference them together (use `m' to mark items, `a' or
917 `A' to use all marked entries).
918
919 *** reftex.el has been split into a number of smaller files to reduce
920 memory use when only a part of RefTeX is being used.
921
922 *** a new command `reftex-view-crossref-from-bibtex' (bound to `C-c &'
923 in BibTeX-mode) can be called in a BibTeX database buffer in order
924 to show locations in LaTeX documents where a particular entry has
925 been cited.
926
927 ** Emacs Lisp mode now allows multiple levels of outline headings.
928 The level of a heading is determined from the number of leading
929 semicolons in a heading line. Toplevel forms starting with a `('
930 in column 1 are always made leaves.
931
932 ** The M-x time-stamp command (most commonly used on write-file-hooks)
933 has the following new features:
934
935 *** The patterns for finding the time stamp and for updating a pattern
936 may match text spanning multiple lines. For example, some people like
937 to have the filename and date on separate lines. The new variable
938 time-stamp-inserts-lines controls the matching for multi-line patterns.
939
940 *** More than one time stamp can be updated in the same file. This
941 feature is useful if you need separate time stamps in a program source
942 file to both include in formatted documentation and insert in the
943 compiled binary. The same time-stamp will be written at each matching
944 pattern. The variable time-stamp-count enables this new feature; it
945 defaults to 1.
946
947 ** Partial Completion mode now completes environment variables in
948 file names.
949
950 +++
951 ** Tooltips.
952
953 Tooltips are small X windows displaying a help string at the current
954 mouse position. To use them, use the Lisp package `tooltip' which you
955 can access via the user option `tooltip-mode'.
956
957 Tooltips also provides support for GUD debugging. If activated,
958 variable values can be displayed in tooltips by pointing at them with
959 the mouse in source buffers. You can customize various aspects of the
960 tooltip display in the group `tooltip'.
961
962 +++
963 ** Customize changes
964
965 *** Customize now supports comments about customized items. Use the
966 `State' menu to add comments. Note that customization comments will
967 cause the customizations to fail in earlier versions of Emacs.
968
969 *** The new option `custom-buffer-done-function' says whether to kill
970 Custom buffers when you've done with them or just bury them (the
971 default).
972
973 *** The keyword :set-after in defcustom allows to specify dependencies
974 between custom options. Example:
975
976 (defcustom default-input-method nil
977 "*Default input method for multilingual text (a string).
978 This is the input method activated automatically by the command
979 `toggle-input-method' (\\[toggle-input-method])."
980 :group 'mule
981 :type '(choice (const nil) string)
982 :set-after '(current-language-environment))
983
984 This specifies that default-input-method should be set after
985 current-language-environment even if default-input-method appears
986 first in a custom-set-variables statement.
987
988 ** New features in evaluation commands
989
990 *** The commands to evaluate Lisp expressions, such as C-M-x in Lisp
991 modes, C-j in Lisp Interaction mode, and M-:, now bind the variables
992 print-level, print-length, and debug-on-error based on the
993 customizable variables eval-expression-print-level,
994 eval-expression-print-length, and eval-expression-debug-on-error.
995
996 *** The function `eval-defun' (M-C-x) now loads Edebug and instruments
997 code when called with a prefix argument.
998
999 ** Ispell changes
1000
1001 +++
1002 *** The command `ispell' now spell-checks a region if
1003 transient-mark-mode is on, and the mark is active. Otherwise it
1004 spell-checks the current buffer.
1005
1006 +++
1007 *** Support for synchronous subprocesses - DOS/Windoze - has been
1008 added.
1009
1010 *** An "alignment error" bug was fixed when a manual spelling
1011 correction is made and re-checked.
1012
1013 *** An Italian and a Portuguese dictionary definition has been added.
1014
1015 *** Region skipping performance has been vastly improved in some
1016 cases.
1017
1018 *** Spell checking HTML buffers has been improved and isn't so strict
1019 on syntax errors.
1020
1021 *** The buffer-local words are now always placed on a new line at the
1022 end of the buffer.
1023
1024 ** Dired changes
1025
1026 *** New variable `dired-recursive-deletes' determines if the delete
1027 command will delete non-empty directories recursively. The default
1028 is, delete only empty directories.
1029
1030 *** New variable `dired-recursive-copies' determines if the copy
1031 command will copy directories recursively. The default is, do not
1032 copy directories recursively.
1033
1034 *** In command `dired-do-shell-command' (usually bound to `!') a `?'
1035 in the shell command has a special meaning similar to `*', but with
1036 the difference that the command will be run on each file individually.
1037
1038 *** The new command `dired-find-alternate-file' (usually bound to `a')
1039 replaces the Dired buffer with the buffer for an alternate file or
1040 directory.
1041
1042 *** The new command `dired-show-file-type' (usually bound to `w') shows
1043 a message in the echo area describing what type of file the point is on.
1044 This command invokes the external program `file' do its work, and so
1045 will only work on systems with that program, and will be only as
1046 accurate or inaccurate as it is.
1047
1048 *** Dired now properly handles undo changes of adding/removing `-R'
1049 from ls switches.
1050
1051 ** The variable mail-specify-envelope-from controls whether to
1052 use the -f option when sending mail.
1053
1054 ** CC mode changes.
1055
1056 Note: This release contains changes that might not be compatible with
1057 current user setups (although it's believed that these
1058 incompatibilities will only show in very uncommon circumstances).
1059 However, since the impact is uncertain, these changes may be rolled
1060 back depending on user feedback. Therefore there's no forward
1061 compatibility guarantee wrt the new features introduced in this
1062 release.
1063
1064 *** c-style-variables-are-local-p now defaults to t.
1065 This is an incompatible change that has been made to make the behavior
1066 of the style system wrt global variable settings less confusing for
1067 non-advanced users. If you know what this variable does you might
1068 want to set it to nil in your .emacs, otherwise you probably don't
1069 have to bother.
1070
1071 Defaulting c-style-variables-are-local-p to t avoids the confusing
1072 situation that occurs when a user sets some style variables globally
1073 and edits both a Java and a non-Java file in the same Emacs session.
1074 If the style variables aren't buffer local in this case, loading of
1075 the second file will cause the default style (either "gnu" or "java"
1076 by default) to override the global settings made by the user.
1077
1078 *** New initialization procedure for the style system.
1079 When the initial style for a buffer is determined by CC Mode (from the
1080 variable c-default-style), the global values of style variables now
1081 take precedence over the values specified by the chosen style. This
1082 is different than the old behavior: previously, the style-specific
1083 settings would override the global settings. This change makes it
1084 possible to do simple configuration in the intuitive way with
1085 Customize or with setq lines in one's .emacs file.
1086
1087 By default, the global value of every style variable is the new
1088 special symbol set-from-style, which causes the value to be taken from
1089 the style system. This means that in effect, only an explicit setting
1090 of a style variable will cause the "overriding" behavior described
1091 above.
1092
1093 Also note that global settings override style-specific settings *only*
1094 when the initial style of a buffer is chosen by a CC Mode major mode
1095 function. When a style is chosen in other ways --- for example, by a
1096 call like (c-set-style "gnu") in a hook, or via M-x c-set-style ---
1097 then the style-specific values take precedence over any global style
1098 values. In Lisp terms, global values override style-specific values
1099 only when the new second argument to c-set-style is non-nil; see the
1100 function documentation for more info.
1101
1102 The purpose of these changes is to make it easier for users,
1103 especially novice users, to do simple customizations with Customize or
1104 with setq in their .emacs files. On the other hand, the new system is
1105 intended to be compatible with advanced users' customizations as well,
1106 such as those that choose styles in hooks or whatnot. This new system
1107 is believed to be almost entirely compatible with current
1108 configurations, in spite of the changed precedence between style and
1109 global variable settings when a buffer's default style is set.
1110
1111 (Thanks to Eric Eide for clarifying this explanation a bit.)
1112
1113 **** c-offsets-alist is now a customizable variable.
1114 This became possible as a result of the new initialization behavior.
1115
1116 This variable is treated slightly differently from the other style
1117 variables; instead of using the symbol set-from-style, it will be
1118 completed with the syntactic symbols it doesn't already contain when
1119 the style is first initialized. This means it now defaults to the
1120 empty list to make all syntactic elements get their values from the
1121 style system.
1122
1123 **** Compatibility variable to restore the old behavior.
1124 In case your configuration doesn't work with this change, you can set
1125 c-old-style-variable-behavior to non-nil to get the old behavior back
1126 as far as possible.
1127
1128 *** Improvements to line breaking and text filling.
1129 CC Mode now handles this more intelligently and seamlessly wrt the
1130 surrounding code, especially inside comments. For details see the new
1131 chapter about this in the manual.
1132
1133 **** New variable to recognize comment line prefix decorations.
1134 The variable c-comment-prefix-regexp has been added to properly
1135 recognize the line prefix in both block and line comments. It's
1136 primarily used to initialize the various paragraph recognition and
1137 adaptive filling variables that the text handling functions uses.
1138
1139 **** New variable c-block-comment-prefix.
1140 This is a generalization of the now obsolete variable
1141 c-comment-continuation-stars to handle arbitrary strings.
1142
1143 **** CC Mode now uses adaptive fill mode.
1144 This to make it adapt better to the paragraph style inside comments.
1145
1146 It's also possible to use other adaptive filling packages inside CC
1147 Mode, notably Kyle E. Jones' Filladapt mode (http://wonderworks.com/).
1148 A new convenience function c-setup-filladapt sets up Filladapt for use
1149 inside CC Mode.
1150
1151 Note though that the 2.12 version of Filladapt lacks a feature that
1152 causes it to work suboptimally when c-comment-prefix-regexp can match
1153 the empty string (which it commonly does). A patch for that is
1154 available from the CC Mode web site (http://www.python.org/emacs/
1155 cc-mode/).
1156
1157 **** It's now possible to selectively turn off auto filling.
1158 The variable c-ignore-auto-fill is used to ignore auto fill mode in
1159 specific contexts, e.g. in preprocessor directives and in string
1160 literals.
1161
1162 **** New context sensitive line break function c-context-line-break.
1163 It works like newline-and-indent in normal code, and adapts the line
1164 prefix according to the comment style when used inside comments. If
1165 you're normally using newline-and-indent, you might want to switch to
1166 this function.
1167
1168 *** Fixes to IDL mode.
1169 It now does a better job in recognizing only the constructs relevant
1170 to IDL. E.g. it no longer matches "class" as the beginning of a
1171 struct block, but it does match the CORBA 2.3 "valuetype" keyword.
1172 Thanks to Eric Eide.
1173
1174 *** Improvements to the Whitesmith style.
1175 It now keeps the style consistently on all levels and both when
1176 opening braces hangs and when they don't.
1177
1178 **** New lineup function c-lineup-whitesmith-in-block.
1179
1180 *** New lineup functions c-lineup-template-args and c-indent-multi-line-block.
1181 See their docstrings for details. c-lineup-template-args does a
1182 better job of tracking the brackets used as parens in C++ templates,
1183 and is used by default to line up continued template arguments.
1184
1185 *** c-lineup-comment now preserves alignment with a comment on the
1186 previous line. It used to instead preserve comments that started in
1187 the column specified by comment-column.
1188
1189 *** c-lineup-C-comments handles "free form" text comments.
1190 In comments with a long delimiter line at the start, the indentation
1191 is kept unchanged for lines that start with an empty comment line
1192 prefix. This is intended for the type of large block comments that
1193 contain documentation with its own formatting. In these you normally
1194 don't want CC Mode to change the indentation.
1195
1196 *** The `c' syntactic symbol is now relative to the comment start
1197 instead of the previous line, to make integers usable as lineup
1198 arguments.
1199
1200 *** All lineup functions have gotten docstrings.
1201
1202 *** More preprocessor directive movement functions.
1203 c-down-conditional does the reverse of c-up-conditional.
1204 c-up-conditional-with-else and c-down-conditional-with-else are
1205 variants of these that also stops at "#else" lines (suggested by Don
1206 Provan).
1207
1208 *** Minor improvements to many movement functions in tricky situations.
1209
1210 ** Makefile mode changes
1211
1212 *** The mode now uses the abbrev table `makefile-mode-abbrev-table'.
1213
1214 *** Conditionals and include statements are now highlighted when
1215 Fontlock mode is active.
1216
1217 ** Isearch changes
1218
1219 *** Isearch now puts a call to `isearch-resume' in the command history,
1220 so that searches can be resumed.
1221
1222 *** In Isearch mode, M-C-s and M-C-r are now bound like C-s and C-r,
1223 respectively, i.e. you can repeat a regexp isearch with the same keys
1224 that started the search.
1225
1226 *** In Isearch mode, mouse-2 in the echo area now yanks the current
1227 selection into the search string rather than giving an error.
1228
1229 +++
1230 *** There is a new lazy highlighting feature in incremental search.
1231
1232 Lazy highlighting is switched on/off by customizing variable
1233 `isearch-lazy-highlight'. When active, all matches for the current
1234 search string are highlighted. The current match is highlighted as
1235 before using face `isearch' or `region'. All other matches are
1236 highlighted using face `isearch-lazy-highlight-face' which defaults to
1237 `secondary-selection'.
1238
1239 The extra highlighting makes it easier to anticipate where the cursor
1240 will end up each time you press C-s or C-r to repeat a pending search.
1241 Highlighting of these additional matches happens in a deferred fashion
1242 using "idle timers," so the cycles needed do not rob isearch of its
1243 usual snappy response.
1244
1245 If `isearch-lazy-highlight-cleanup' is set to t, highlights for
1246 matches are automatically cleared when you end the search. If it is
1247 set to nil, you can remove the highlights manually with `M-x
1248 isearch-lazy-highlight-cleanup'.
1249
1250 +++
1251 ** Changes in sort.el
1252
1253 The function sort-numeric-fields interprets numbers starting with `0'
1254 as octal and numbers starting with `0x' or `0X' as hexadecimal. The
1255 new user-option sort-numeric-base can be used to specify a default
1256 numeric base.
1257
1258 ** Changes to Ange-ftp
1259
1260 +++
1261 *** Ange-ftp allows you to specify of a port number in remote file
1262 names cleanly. It is appended to the host name, separated by a hash
1263 sign, e.g. `/foo@bar.org#666:mumble'. (This syntax comes from EFS.)
1264
1265 *** If the new user-option `ange-ftp-try-passive-mode' is set, passive
1266 ftp mode will be used if the ftp client supports that.
1267
1268 *** Ange-ftp handles the output of the w32-style clients which
1269 output ^M at the end of lines.
1270
1271 ** Shell script mode changes.
1272
1273 Shell script mode (sh-script) can now indent scripts for shells
1274 derived from sh and rc. The indentation style is customizeable, and
1275 sh-script can attempt to "learn" the current buffer's style.
1276
1277 ** Etags changes.
1278
1279 *** In DOS, etags looks for file.cgz if it cannot find file.c.
1280
1281 *** New option --ignore-case-regex is an alternative to --regex. It is now
1282 possible to bind a regexp to a language, by prepending the regexp with
1283 {lang}, where lang is one of the languages that `etags --help' prints out.
1284 This feature is useful especially for regex files, where each line contains
1285 a regular expression. The manual contains details.
1286
1287 *** In C and derived languages, etags creates tags for function
1288 declarations when given the --declarations option.
1289
1290 *** In C++, tags are created for "operator". The tags have the form
1291 "operator+", without spaces between the keyword and the operator.
1292
1293 *** New language Ada: tags are functions, procedures, packages, tasks, and
1294 types.
1295
1296 *** In Fortran, `procedure' is not tagged.
1297
1298 *** In Java, tags are created for "interface".
1299
1300 *** In Lisp, "(defstruct (foo", "(defun (operator" and similar constructs
1301 are now tagged.
1302
1303 *** In Perl, the --globals option tags global variables. my and local
1304 variables are tagged.
1305
1306 *** New language Python: def and class at the beginning of a line are tags.
1307
1308 *** .ss files are Scheme files, .pdb is Postscript with C syntax, .psw is
1309 for PSWrap.
1310
1311 +++
1312 ** Changes in etags.el
1313
1314 *** The new user-option tags-case-fold-search can be used to make
1315 tags operations case-sensitive or case-insensitive. The default
1316 is to use the same setting as case-fold-search.
1317
1318 *** You can display additional output with M-x tags-apropos by setting
1319 the new variable tags-apropos-additional-actions.
1320
1321 If non-nil, the variable's value should be a list of triples (TITLE
1322 FUNCTION TO-SEARCH). For each triple, M-x tags-apropos processes
1323 TO-SEARCH and lists tags from it. TO-SEARCH should be an alist,
1324 obarray, or symbol. If it is a symbol, the symbol's value is used.
1325
1326 TITLE is a string to use to label the list of tags from TO-SEARCH.
1327
1328 FUNCTION is a function to call when an entry is selected in the Tags
1329 List buffer. It is called with one argument, the selected symbol.
1330
1331 A useful example value for this variable might be something like:
1332
1333 '(("Emacs Lisp" Info-goto-emacs-command-node obarray)
1334 ("Common Lisp" common-lisp-hyperspec common-lisp-hyperspec-obarray)
1335 ("SCWM" scwm-documentation scwm-obarray))
1336
1337 *** The face tags-tag-face can be used to customize the appearance
1338 of tags in the output of M-x tags-apropos.
1339
1340 *** Setting tags-apropos-verbose to a non-nil value displays the
1341 names of tags files in the *Tags List* buffer.
1342
1343 +++
1344 ** Emacs now attempts to determine the initial language environment
1345 and preferred and locale coding systems systematically from the
1346 LC_ALL, LC_CTYPE, and LANG environment variables during startup.
1347
1348 +++
1349 ** New language environments `Polish', `Latin-8' and `Latin-9'.
1350 Latin-8 and Latin-9 correspond respectively to the ISO character sets
1351 8859-14 (Celtic) and 8859-15 (updated Latin-1, with the Euro sign).
1352 GNU Intlfonts doesn't support these yet; there are basic 8859-14 and
1353 8859-15 fonts at <URL:http://czyborra.com/charsets/> and recent X
1354 releases have 8859-15. There are new Latin-8 and Latin-9 prefix
1355 (only) and Polish slash input methods in Leim.
1356
1357 +++
1358 ** Fortran mode has a new command `fortran-strip-sequence-nos' to
1359 remove text past column 72. The syntax class of `\' in Fortran is now
1360 appropriate for C-style escape sequences in strings.
1361
1362 ** SGML mode's default `sgml-validate-command' is now `nsgmls'.
1363
1364 +++
1365 ** A new command `view-emacs-problems' (C-h P) displays the PROBLEMS file.
1366
1367 +++
1368 ** The Dabbrev package has a new user-option `dabbrev-ignored-regexps'
1369 containing a list of regular expressions. Buffers matching a regular
1370 expression from that list, are not checked.
1371
1372 ** Emacs can now figure out modification times of remote files.
1373 When you do C-x C-f /user@host:/path/file RET and edit the file,
1374 and someone else modifies the file, you will be prompted to revert
1375 the buffer, just like for the local files.
1376
1377 ** The buffer menu (C-x C-b) no longer lists the *Buffer List* buffer.
1378
1379 +++
1380 ** When invoked with a prefix argument, the command `list-abbrevs' now
1381 displays local abbrevs, only.
1382
1383 ** VC Changes
1384
1385 VC has been overhauled internally. It is now modular, making it
1386 easier to plug-in arbitrary version control backends. (See Lisp
1387 Changes for details on the new structure.) As a result, the mechanism
1388 to enable and disable support for particular version systems has
1389 changed: everything is now controlled by the new variable
1390 `vc-handled-backends'. Its value is a list of atoms that identify
1391 version systems; the default is '(RCS CVS SCCS). When finding a file,
1392 each of the backends in that list is tried in order to see whether the
1393 file is registered in that backend.
1394
1395 When registering a new file, VC first tries each of the listed
1396 backends to see if any of them considers itself "responsible" for the
1397 directory of the file (e.g. because a corresponding subdirectory for
1398 master files exists). If none of the backends is responsible, then
1399 the first backend in the list that could register the file is chosen.
1400 As a consequence, the variable `vc-default-back-end' is now obsolete.
1401
1402 The old variable `vc-master-templates' is also obsolete, although VC
1403 still supports it for backward compatibility. To define templates for
1404 RCS or SCCS, you should rather use the new variables
1405 vc-{rcs,sccs}-master-templates. (There is no such feature under CVS
1406 where it doesn't make sense.)
1407
1408 The variables `vc-ignore-vc-files' and `vc-handle-cvs' are also
1409 obsolete now, you must set `vc-handled-backends' to nil or exclude
1410 `CVS' from the list, respectively, to achieve their effect now.
1411
1412 *** General Changes
1413
1414 The variable `vc-checkout-carefully' is obsolete: the corresponding
1415 checks are always done now.
1416
1417 VC Dired buffers are now kept up-to-date during all version control
1418 operations.
1419
1420 *** Changes for CVS
1421
1422 There is a new user option, `vc-cvs-stay-local'. If it is `t' (the
1423 default), then VC avoids network queries for files registered in
1424 remote repositories. The state of such files is then only determined
1425 by heuristics and past information. `vc-cvs-stay-local' can also be a
1426 regexp to match against repository hostnames; only files from hosts
1427 that match it are treated locally. If the variable is nil, then VC
1428 queries the repository just as often as it does for local files.
1429
1430 If `vc-cvs-stay-local' is on, and there have been changes in the
1431 repository, VC notifies you about it when you actually try to commit.
1432 If you want to check for updates from the repository without trying to
1433 commit, you can either use C-u C-x v m to perform an update on the
1434 current file, or you can use C-x v r RET to get an update for an
1435 entire directory tree.
1436
1437 The new user option `vc-cvs-use-edit' indicates whether VC should call
1438 "cvs edit" to make files writeable; it defaults to `t'. (This option
1439 is only meaningful if the CVSREAD variable is set, or if files are
1440 "watched" by other developers.)
1441
1442 *** Lisp Changes in VC
1443
1444 VC has been restructured internally to make it modular. You can now
1445 add support for arbitrary version control backends by writing a
1446 library that provides a certain set of backend-specific functions, and
1447 then telling VC to use that library. For example, to add support for
1448 a version system named FOO, you write a library named vc-foo.el, which
1449 provides a number of functions vc-foo-... (see commentary at the end
1450 of vc.el for a detailed list of them). To make VC use that library,
1451 you need to put it somewhere into Emacs' load path and add the atom
1452 `FOO' to the list `vc-handled-backends'.
1453
1454 ** New modes and packages
1455
1456 +++
1457 *** The new package timeclock.el is a mode is for keeping track of time
1458 intervals. You can use it for whatever purpose you like, but the
1459 typical scenario is to keep track of how much time you spend working
1460 on certain projects.
1461
1462 +++
1463 *** The new package hi-lock.el, text matching interactively entered
1464 regexp's can be highlighted. For example,
1465
1466 M-x highlight-regexp RET clearly RET RET
1467
1468 will highlight all occurrences of `clearly' using a yellow background
1469 face. New occurrences of `clearly' will be highlighted as they are
1470 typed. `M-x unhighlight-regexp RET' will remove the highlighting.
1471 Any existing face can be used for highlighting and a set of
1472 appropriate faces is provided. The regexps can be written into the
1473 current buffer in a form that will be recognized the next time the
1474 corresponding file is read.
1475
1476 +++
1477 *** The new package zone.el plays games with Emacs' display when
1478 Emacs is idle.
1479
1480 *** The new package xml.el provides a simple but generic XML
1481 parser. It doesn't parse the DTDs however.
1482
1483 *** The comment operations are now provided by the newcomment.el
1484 package which allows different styles of comment-region and should
1485 be more robust while offering the same functionality.
1486
1487 +++
1488 *** The Ebrowse package implements a C++ class browser and tags
1489 facilities tailored for use with C++. It is documented in a
1490 separate Texinfo file.
1491
1492 +++
1493 *** The PCL-CVS package available by either running M-x cvs-examine or
1494 by visiting a CVS administrative directory (with a prefix argument)
1495 provides an alternative interface to VC-dired for CVS. It comes with
1496 `log-view-mode' to view RCS and SCCS logs and `log-edit-mode' used to
1497 enter checkin log messages.
1498
1499 +++
1500 *** The new package called `woman' allows to browse Unix man pages
1501 without invoking external programs.
1502
1503 The command `M-x woman' formats manual pages entirely in Emacs Lisp
1504 and then displays them, like `M-x manual-entry' does. Unlike
1505 `manual-entry', `woman' does not invoke any external programs, so it
1506 is useful on systems such as MS-DOS/MS-Windows where the `man' and
1507 Groff or `troff' commands are not readily available.
1508
1509 The command `M-x woman-find-file' asks for the file name of a man
1510 page, then formats and displays it like `M-x woman' does.
1511
1512 +++
1513 *** The new command M-x re-builder offers a convenient interface for
1514 authoring regular expressions with immediate visual feedback.
1515
1516 The buffer from which the command was called becomes the target for
1517 the regexp editor popping up in a separate window. Matching text in
1518 the target buffer is immediately color marked during the editing.
1519 Each sub-expression of the regexp will show up in a different face so
1520 even complex regexps can be edited and verified on target data in a
1521 single step.
1522
1523 On displays not supporting faces the matches instead blink like
1524 matching parens to make them stand out. On such a setup you will
1525 probably also want to use the sub-expression mode when the regexp
1526 contains such to get feedback about their respective limits.
1527
1528 +++
1529 *** glasses-mode is a minor mode that makes
1530 unreadableIdentifiersLikeThis readable. It works as glasses, without
1531 actually modifying content of a buffer.
1532
1533 *** The package ebnf2ps translates an EBNF to a syntactic chart in
1534 PostScript.
1535
1536 Currently accepts ad-hoc EBNF, ISO EBNF and Bison/Yacc.
1537
1538 The ad-hoc default EBNF syntax has the following elements:
1539
1540 ; comment (until end of line)
1541 A non-terminal
1542 "C" terminal
1543 ?C? special
1544 $A default non-terminal
1545 $"C" default terminal
1546 $?C? default special
1547 A = B. production (A is the header and B the body)
1548 C D sequence (C occurs before D)
1549 C | D alternative (C or D occurs)
1550 A - B exception (A excluding B, B without any non-terminal)
1551 n * A repetition (A repeats n (integer) times)
1552 (C) group (expression C is grouped together)
1553 [C] optional (C may or not occurs)
1554 C+ one or more occurrences of C
1555 {C}+ one or more occurrences of C
1556 {C}* zero or more occurrences of C
1557 {C} zero or more occurrences of C
1558 C / D equivalent to: C {D C}*
1559 {C || D}+ equivalent to: C {D C}*
1560 {C || D}* equivalent to: [C {D C}*]
1561 {C || D} equivalent to: [C {D C}*]
1562
1563 Please, see ebnf2ps documentation for EBNF syntax and how to use it.
1564
1565 *** The package align.el will align columns within a region, using M-x
1566 align. Its mode-specific rules, based on regular expressions,
1567 determine where the columns should be split. In C and C++, for
1568 example, it will align variable names in declaration lists, or the
1569 equal signs of assignments.
1570
1571 +++
1572 *** `paragraph-indent-minor-mode' is a new minor mode supporting
1573 paragraphs in the same style as `paragraph-indent-text-mode'.
1574
1575 +++
1576 *** bs.el is a new package for buffer selection similar to
1577 list-buffers or electric-buffer-list. Use M-x bs-show to display a
1578 buffer menu with this package. You can use M-x bs-customize to
1579 customize the package.
1580
1581 *** find-lisp.el is a package emulating the Unix find command in Lisp.
1582
1583 *** calculator.el is a small calculator package that is intended to
1584 replace desktop calculators such as xcalc and calc.exe. Actually, it
1585 is not too small - it has more features than most desktop calculators,
1586 and can be customized easily to get many more functions. It should
1587 not be confused with "calc" which is a much bigger mathematical tool
1588 which answers different needs.
1589
1590 +++
1591 *** The minor modes cwarn-mode and global-cwarn-mode highlights
1592 suspicious C and C++ constructions. Currently, assignments inside
1593 expressions, semicolon following `if', `for' and `while' (except, of
1594 course, after a `do .. while' statement), and C++ functions with
1595 reference parameters are recognized. The modes require font-lock mode
1596 to be enabled.
1597
1598 +++
1599 *** smerge-mode.el provides `smerge-mode', a simple minor-mode for files
1600 containing diff3-style conflict markers, such as generated by RCS.
1601
1602 +++
1603 *** 5x5.el is a simple puzzle game.
1604
1605 +++
1606 *** hl-line.el provides a minor mode to highlight the current line.
1607
1608 *** ansi-color.el translates ANSI terminal escapes into text-properties.
1609
1610 Please note: if `ansi-color-for-shell-mode' and
1611 `global-font-lock-mode' are non-nil, loading ansi-color.el will
1612 disable font-lock and add `ansi-color-apply' to
1613 `comint-preoutput-filter-functions' for all shell-mode buffers. This
1614 displays the output of "ls --color=yes" using the correct foreground
1615 and background colors.
1616
1617 *** delphi.el provides a major mode for editing the Delphi (Object
1618 Pascal) language.
1619
1620 +++
1621 *** quickurl.el provides a simple method of inserting a URL based on
1622 the text at point.
1623
1624 *** sql.el provides an interface to SQL data bases.
1625
1626 +++
1627 *** fortune.el uses the fortune program to create mail/news signatures.
1628
1629 *** whitespace.el ???
1630
1631 *** PostScript mode (ps-mode) is a new major mode for editing PostScript
1632 files. It offers: interaction with a PostScript interpreter, including
1633 (very basic) error handling; fontification, easily customizable for
1634 interpreter messages; auto-indentation; insertion of EPSF templates and
1635 often used code snippets; viewing of BoundingBox; commenting out /
1636 uncommenting regions; conversion of 8bit characters to PostScript octal
1637 codes. All functionality is accessible through a menu.
1638
1639 *** delim-col helps to prettify columns in a text region or rectangle.
1640
1641 Here is an example of columns:
1642
1643 horse apple bus
1644 dog pineapple car EXTRA
1645 porcupine strawberry airplane
1646
1647 Doing the following settings:
1648
1649 (setq delimit-columns-str-before "[ ")
1650 (setq delimit-columns-str-after " ]")
1651 (setq delimit-columns-str-separator ", ")
1652 (setq delimit-columns-separator "\t")
1653
1654
1655 Selecting the lines above and typing:
1656
1657 M-x delimit-columns-region
1658
1659 It results:
1660
1661 [ horse , apple , bus , ]
1662 [ dog , pineapple , car , EXTRA ]
1663 [ porcupine, strawberry, airplane, ]
1664
1665 delim-col has the following options:
1666
1667 delimit-columns-str-before Specify a string to be inserted
1668 before all columns.
1669
1670 delimit-columns-str-separator Specify a string to be inserted
1671 between each column.
1672
1673 delimit-columns-str-after Specify a string to be inserted
1674 after all columns.
1675
1676 delimit-columns-separator Specify a regexp which separates
1677 each column.
1678
1679 delim-col has the following commands:
1680
1681 delimit-columns-region Prettify all columns in a text region.
1682 delimit-columns-rectangle Prettify all columns in a text rectangle.
1683
1684 +++
1685 *** The package recentf.el maintains a menu for visiting files that
1686 were operated on recently.
1687
1688 M-x recentf-mode RET toggles recentf mode.
1689
1690 M-x customize-variable RET recentf-mode RET can be used to enable
1691 recentf at Emacs startup.
1692
1693 M-x customize-variable RET recentf-menu-filter RET to specify a menu
1694 filter function to change the menu appearance. For example, the recent
1695 file list can be displayed:
1696
1697 - organized by major modes, directories or user defined rules.
1698 - sorted by file pathes, file names, ascending or descending.
1699 - showing pathes relative to the current default-directory
1700
1701 The `recentf-filter-changer' menu filter function allows to
1702 dynamically change the menu appearance.
1703
1704 *** elide-head.el provides a mechanism for eliding boilerplate header
1705 text.
1706
1707 +++
1708 *** footnote.el provides `footnote-mode', a minor mode supporting use
1709 of footnotes. It is intended for use with Message mode, but isn't
1710 specific to Message mode.
1711
1712 +++
1713 *** diff-mode.el provides `diff-mode', a major mode for
1714 viewing/editing context diffs (patches). It is selected for files
1715 with extension `.diff', `.diffs', `.patch' and `.rej'.
1716
1717 +++
1718 *** EUDC, the Emacs Unified Directory Client, provides a common user
1719 interface to access directory servers using different directory
1720 protocols. It has a separate manual.
1721
1722 *** autoconf.el provides a major mode for editing configure.in files
1723 for Autoconf, selected automatically.
1724
1725 +++
1726 *** windmove.el provides moving between windows.
1727
1728 *** crm.el provides a facility to read multiple strings from the
1729 minibuffer with completion.
1730
1731 *** todo-mode.el provides management of TODO lists and integration
1732 with the diary features.
1733
1734 *** autoarg.el provides a feature reported from Twenex Emacs whereby
1735 numeric keys supply prefix args rather than self inserting.
1736
1737 *** The function `turn-off-auto-fill' unconditionally turns off Auto
1738 Fill mode.
1739
1740 *** gnus-mule.el is now just a compatibility layer over the built-in
1741 Gnus facilities.
1742
1743 ** Withdrawn packages
1744
1745 *** mldrag.el has been removed. mouse.el provides the same
1746 functionality with aliases for the mldrag functions.
1747
1748 *** eval-reg.el has been obsoleted by changes to edebug.el and removed.
1749
1750 *** ph.el has been obsoleted by EUDC and removed.
1751
1752 \f
1753 * Lisp changes made after edition 2.6 of the Emacs Lisp Manual,
1754 (Display-related features are described in a page of their own below.)
1755
1756 +++
1757 ** The new function `display-message-or-buffer' displays a message in
1758 the echo area or pops up a buffer, depending on the length of the
1759 message.
1760
1761 ** The new macro `with-auto-compression-mode' allows evaluating an
1762 expression with auto-compression-mode enabled.
1763
1764 ** In image specifications, `:heuristic-mask' has been replaced
1765 with the more general `:mask' property.
1766
1767 ** Image specifications accept more `:algorithm's.
1768
1769 ** A `?' can be used in a symbol name without escaping it with a
1770 backslash.
1771
1772 +++
1773 ** Reading from the mini-buffer now reads from standard input if Emacs
1774 is running in batch mode. For example,
1775
1776 (message "%s" (read t))
1777
1778 will read a Lisp expression from standard input and print the result
1779 to standard output.
1780
1781 +++
1782 ** The argument of `down-list', `backward-up-list', `up-list',
1783 `kill-sexp', `backward-kill-sexp' and `mark-sexp' is now optional.
1784
1785 ** If `display-buffer-reuse-frames' is set, function `display-buffer'
1786 will raise frames displaying a buffer, instead of creating a new
1787 frame or window.
1788
1789 +++
1790 ** Two new functions for removing elements from lists/sequences
1791 were added
1792
1793 - Function: remove ELT SEQ
1794
1795 Return a copy of SEQ with all occurences of ELT removed. SEQ must be
1796 a list, vector, or string. The comparison is done with `equal'.
1797
1798 - Function: remq ELT LIST
1799
1800 Return a copy of LIST with all occurences of ELT removed. The
1801 comparison is done with `eq'.
1802
1803 ** The function `delete' now also works with vectors and strings.
1804
1805 ** The meaning of the `:weakness WEAK' argument of make-hash-table
1806 has been changed.
1807
1808 +++
1809 ** Function `aset' stores any multibyte character in any string
1810 without signaling "Attempt to change char length of a string". It may
1811 convert a unibyte string to multibyte if necessary.
1812
1813 ** The value of the `help-echo' text property is called as a function
1814 or evaluated, if it is not a string already, to obtain a help string.
1815
1816 ** Function `make-obsolete' now has an optional arg to say when the
1817 function was declared obsolete.
1818
1819 ** Function `plist-member' is renamed from `widget-plist-member' (which is
1820 retained as an alias).
1821
1822 ** Easy-menu's :filter now works as in XEmacs.
1823 It takes the unconverted (i.e. XEmacs) form of the menu and the result
1824 is automatically converted to Emacs' form.
1825
1826 ** The new function `window-list' has been defined
1827
1828 - Function: window-list &optional WINDOW MINIBUF ALL-FRAMES
1829
1830 Return a list of windows in canonical order. The parameters WINDOW,
1831 MINIBUF and ALL-FRAMES are defined like for `next-window'.
1832
1833 ** There's a new function `some-window' defined as follows
1834
1835 - Function: some-window PREDICATE &optional MINIBUF ALL-FRAMES DEFAULT
1836
1837 Return a window satisfying PREDICATE.
1838
1839 This function cycles through all visible windows using `walk-windows',
1840 calling PREDICATE on each one. PREDICATE is called with a window as
1841 argument. The first window for which PREDICATE returns a non-nil
1842 value is returned. If no window satisfies PREDICATE, DEFAULT is
1843 returned.
1844
1845 Optional second arg MINIBUF t means count the minibuffer window even
1846 if not active. MINIBUF nil or omitted means count the minibuffer iff
1847 it is active. MINIBUF neither t nor nil means not to count the
1848 minibuffer even if it is active.
1849
1850 Several frames may share a single minibuffer; if the minibuffer
1851 counts, all windows on all frames that share that minibuffer count
1852 too. Therefore, if you are using a separate minibuffer frame
1853 and the minibuffer is active and MINIBUF says it counts,
1854 `walk-windows' includes the windows in the frame from which you
1855 entered the minibuffer, as well as the minibuffer window.
1856
1857 ALL-FRAMES is the optional third argument.
1858 ALL-FRAMES nil or omitted means cycle within the frames as specified above.
1859 ALL-FRAMES = `visible' means include windows on all visible frames.
1860 ALL-FRAMES = 0 means include windows on all visible and iconified frames.
1861 ALL-FRAMES = t means include windows on all frames including invisible frames.
1862 If ALL-FRAMES is a frame, it means include windows on that frame.
1863 Anything else means restrict to the selected frame.
1864
1865 ** The function `single-key-description' now encloses function key and
1866 event names in angle brackets. When called with a second optional
1867 argument non-nil, angle brackets won't be printed.
1868
1869 ** If the variable `message-truncate-lines' is bound to t around a
1870 call to `message', the echo area will not be resized to display that
1871 message; it will be truncated instead, as it was done in 20.x.
1872 Default value is nil.
1873
1874 ** The user option `line-number-display-limit' can now be set to nil,
1875 meaning no limit.
1876
1877 ** `select-safe-coding-system' now also checks the most preferred
1878 coding-system if buffer-file-coding-system is `undecided' and
1879 DEFAULT-CODING-SYSTEM is not specified,
1880
1881 ** The function `subr-arity' provides information on the argument list
1882 of a primitive.
1883
1884 ** The text property `keymap' specifies a key map which overrides the
1885 buffer's local map and the map specified by the `local-map' property.
1886 This is probably what most current uses of `local-map' want, rather
1887 than replacing the local map.
1888
1889 ** The obsolete variables before-change-function and
1890 after-change-function are no longer acted upon and have been removed.
1891
1892 ** The function `apropos-mode' runs the hook `apropos-mode-hook'.
1893
1894 +++
1895 ** `concat' no longer accepts individual integer arguments, as
1896 promised long ago.
1897
1898 ** The new function `float-time' returns the current time as a float.
1899 \f
1900 * Lisp changes in Emacs 21.1 (see following page for display-related features)
1901
1902 Note that +++ before an item means the Lisp manual has been updated.
1903 --- means that I have decided it does not need to be in the Lisp manual.
1904 When you add a new item, please add it without either +++ or ---
1905 so I will know I still need to look at it -- rms.
1906
1907 *** The special form `save-restriction' now works correctly even if the
1908 buffer is widened inside the save-restriction and changes made outside
1909 the original restriction. Previously, doing this would cause the saved
1910 restriction to be restored incorrectly.
1911
1912 *** The functions `find-charset-region' and `find-charset-string' include
1913 `eight-bit-control' and/or `eight-bit-graphic' in the returned list
1914 when it finds 8-bit characters. Previously, it included `ascii' in a
1915 multibyte buffer and `unknown' in a unibyte buffer.
1916
1917 *** The functions `set-buffer-modified', `string-as-multibyte' and
1918 `string-as-unibyte' change the byte sequence of a buffer if it
1919 contains a character from the `eight-bit-control' character set.
1920
1921 *** The handling of multibyte sequences in a multibyte buffer is
1922 changed. Previously, a byte sequence matching the pattern
1923 [\200-\237][\240-\377]+ was interpreted as a single character
1924 regardless of the length of the trailing bytes [\240-\377]+. Thus, if
1925 the sequence was longer than what the leading byte indicated, the
1926 extra trailing bytes were ignored by Lisp functions. Now such extra
1927 bytes are independent 8-bit characters belonging to the charset
1928 eight-bit-graphic.
1929
1930 ** Fontsets are now implemented using char-tables.
1931
1932 A fontset can now be specified for for each independent character, for
1933 a group of characters or for a character set rather than just for a
1934 character set as previously.
1935
1936 *** The arguments of the function `set-fontset-font' are changed.
1937 They are NAME, CHARACTER, FONTNAME, and optional FRAME. The function
1938 modifies fontset NAME to use FONTNAME for CHARACTER.
1939
1940 CHARACTER may be a cons (FROM . TO), where FROM and TO are non-generic
1941 characters. In that case FONTNAME is used for all characters in the
1942 range FROM and TO (inclusive). CHARACTER may be a charset. In that
1943 case FONTNAME is used for all character in the charset.
1944
1945 FONTNAME may be a cons (FAMILY . REGISTRY), where FAMILY is the family
1946 name of a font and REGSITRY is a registry name of a font.
1947
1948 *** Variable x-charset-registry has been deleted. The default charset
1949 registries of character sets are set in the default fontset
1950 "fontset-default".
1951
1952 *** The function `create-fontset-from-fontset-spec' ignores the second
1953 argument STYLE-VARIANT. It never creates style-variant fontsets.
1954
1955 ** The method of composing characters is changed. Now character
1956 composition is done by a special text property `composition' in
1957 buffers and strings.
1958
1959 *** Charset composition is deleted. Emacs never creates a `composite
1960 character' which is an independent character with a unique character
1961 code. Thus the following functions handling `composite characters'
1962 have been deleted: composite-char-component,
1963 composite-char-component-count, composite-char-composition-rule,
1964 composite-char-composition-rule and decompose-composite-char delete.
1965 The variables leading-code-composition and min-composite-char have
1966 also been deleted.
1967
1968 *** Three more glyph reference points are added. They can be used to
1969 specify a composition rule. See the documentation of the variable
1970 `reference-point-alist' for more detail.
1971
1972 *** The function `compose-region' takes new arguments COMPONENTS and
1973 MODIFICATION-FUNC. With COMPONENTS, you can specify not only a
1974 composition rule but also characters to be composed. Such characters
1975 may differ between buffer and string text.
1976
1977 *** The function `compose-string' takes new arguments START, END,
1978 COMPONENTS, and MODIFICATION-FUNC.
1979
1980 *** The function `compose-string' puts text property `composition'
1981 directly on the argument STRING instead of returning a new string.
1982 Likewise, the function `decompose-string' just removes text property
1983 `composition' from STRING.
1984
1985 *** The new function `find-composition' returns information about
1986 a composition at a specified position in a buffer or a string.
1987
1988 *** The function `decompose-composite-char' is now labeled as
1989 obsolete.
1990
1991 ** The new character set `mule-unicode-0100-24ff' is introduced for
1992 Unicode characters of the range U+0100..U+24FF. Currently, this
1993 character set is not used.
1994
1995 ** The new character sets `japanese-jisx0213-1' and
1996 `japanese-jisx0213-2' are introduced for the new Japanese standard JIS
1997 X 0213 Plane 1 and Plane 2.
1998
1999 +++
2000 ** The new character sets `eight-bit-control' and `eight-bit-graphic'
2001 are introduced for 8-bit characters in the ranges 0x80..0x9F and
2002 0xA0..0xFF respectively.
2003
2004 +++
2005 ** If the APPEND argument of `write-region' is an integer, it seeks to
2006 that offset in the file before writing.
2007
2008 ** The function `add-minor-mode' has been added for convenience and
2009 compatibility with XEmacs (and is used internally by define-minor-mode).
2010
2011 ** The function `shell-command' now sets the default directory of the
2012 `*Shell Command Output*' buffer to the default directory of the buffer
2013 from which the command was issued.
2014
2015 ** The functions `query-replace', `query-replace-regexp',
2016 `query-replace-regexp-eval' `map-query-replace-regexp',
2017 `replace-string', `replace-regexp', and `perform-replace' take two
2018 additional optional arguments START and END that specify the region to
2019 operate on.
2020
2021 ** The new function `count-screen-lines' is a more flexible alternative
2022 to `window-buffer-height'.
2023
2024 - Function: count-screen-lines &optional BEG END COUNT-FINAL-NEWLINE WINDOW
2025
2026 Return the number of screen lines in the region between BEG and END.
2027 The number of screen lines may be different from the number of actual
2028 lines, due to line breaking, display table, etc.
2029
2030 Optional arguments BEG and END default to `point-min' and `point-max'
2031 respectively.
2032
2033 If region ends with a newline, ignore it unless optinal third argument
2034 COUNT-FINAL-NEWLINE is non-nil.
2035
2036 The optional fourth argument WINDOW specifies the window used for
2037 obtaining parameters such as width, horizontal scrolling, and so
2038 on. The default is to use the selected window's parameters.
2039
2040 Like `vertical-motion', `count-screen-lines' always uses the current
2041 buffer, regardless of which buffer is displayed in WINDOW. This makes
2042 possible to use `count-screen-lines' in any buffer, whether or not it
2043 is currently displayed in some window.
2044
2045 ** The new function `mapc' is like `mapcar' but doesn't collect the
2046 argument function's results.
2047
2048 ** The functions base64-decode-region and base64-decode-string now
2049 signal an error instead of returning nil if decoding fails.
2050
2051 ** The function sendmail-user-agent-compose now recognizes a `body'
2052 header in the list of headers passed to it.
2053
2054 ** The new function member-ignore-case works like `member', but
2055 ignores differences in case and text representation.
2056
2057 ** The buffer-local variable cursor-type can be used to specify the
2058 cursor to use in windows displaying a buffer. Values are interpreted
2059 as follows:
2060
2061 t use the cursor specified for the frame (default)
2062 nil don't display a cursor
2063 `bar' display a bar cursor with default width
2064 (bar . WIDTH) display a bar cursor with width WIDTH
2065 others display a box cursor.
2066
2067 ** The variable open-paren-in-column-0-is-defun-start controls whether
2068 an open parenthesis in column 0 is considered to be the start of a
2069 defun. If set, the default, it is considered a defun start. If not
2070 set, an open parenthesis in column 0 has no special meaning.
2071
2072 ** The new function `string-to-syntax' can be used to translate syntax
2073 specifications in string form as accepted by `modify-syntax-entry' to
2074 the cons-cell form that is used for the values of the `syntax-table'
2075 text property, and in `font-lock-syntactic-keywords'.
2076
2077 Example:
2078
2079 (string-to-syntax "()")
2080 => (4 . 41)
2081
2082 ** Emacs' reader supports CL read syntax for integers in bases
2083 other than 10.
2084
2085 *** `#BINTEGER' or `#bINTEGER' reads INTEGER in binary (radix 2).
2086 INTEGER optionally contains a sign.
2087
2088 #b1111
2089 => 15
2090 #b-1111
2091 => -15
2092
2093 *** `#OINTEGER' or `#oINTEGER' reads INTEGER in octal (radix 8).
2094
2095 #o666
2096 => 438
2097
2098 *** `#XINTEGER' or `#xINTEGER' reads INTEGER in hexadecimal (radix 16).
2099
2100 #xbeef
2101 => 48815
2102
2103 *** `#RADIXrINTEGER' reads INTEGER in radix RADIX, 2 <= RADIX <= 36.
2104
2105 #2R-111
2106 => -7
2107 #25rah
2108 => 267
2109
2110 ** The function `documentation-property' now evaluates the value of
2111 the given property to obtain a string if it doesn't refer to etc/DOC
2112 and isn't a string.
2113
2114 ** If called for a symbol, the function `documentation' now looks for
2115 a `function-documentation' property of that symbol. If it has a non-nil
2116 value, the documentation is taken from that value. If the value is
2117 not a string, it is evaluated to obtain a string.
2118
2119 +++
2120 ** The last argument of `define-key-after' defaults to t for convenience.
2121
2122 ** The new function `replace-regexp-in-string' replaces all matches
2123 for a regexp in a string.
2124
2125 ** `mouse-position' now runs the abnormal hook
2126 `mouse-position-function'.
2127
2128 ** The function string-to-number now returns a float for numbers
2129 that don't fit into a Lisp integer.
2130
2131 ** The variable keyword-symbols-constants-flag has been removed.
2132 Keywords are now always considered constants.
2133
2134 +++
2135 ** The new function `delete-and-extract-region' deletes text and
2136 returns it.
2137
2138 ** The function `clear-this-command-keys' now also clears the vector
2139 returned by function `recent-keys'.
2140
2141 +++
2142 ** Variables `beginning-of-defun-function' and `end-of-defun-function'
2143 can be used to define handlers for the functions that find defuns.
2144 Major modes can define these locally instead of rebinding M-C-a
2145 etc. if the normal conventions for defuns are not appropriate for the
2146 mode.
2147
2148 +++
2149 ** easy-mmode-define-minor-mode now takes an additional BODY argument
2150 and is renamed `define-minor-mode'.
2151
2152 +++
2153 ** If an abbrev has a hook function which is a symbol, and that symbol
2154 has a non-nil `no-self-insert' property, the return value of the hook
2155 function specifies whether an expansion has been done or not. If it
2156 returns nil, abbrev-expand also returns nil, meaning "no expansion has
2157 been performed."
2158
2159 When abbrev expansion is done by typing a self-inserting character,
2160 and the abbrev has a hook with the `no-self-insert' property, and the
2161 hook function returns non-nil meaning expansion has been done,
2162 then the self-inserting character is not inserted.
2163
2164 +++
2165 ** The function `intern-soft' now accepts a symbol as first argument.
2166 In this case, that exact symbol is looked up in the specified obarray,
2167 and the function's value is nil if it is not found.
2168
2169 +++
2170 ** The new macro `with-syntax-table' can be used to evaluate forms
2171 with the syntax table of the current buffer temporarily set to a
2172 specified table.
2173
2174 (with-syntax-table TABLE &rest BODY)
2175
2176 Evaluate BODY with syntax table of current buffer set to a copy of
2177 TABLE. The current syntax table is saved, BODY is evaluated, and the
2178 saved table is restored, even in case of an abnormal exit. Value is
2179 what BODY returns.
2180
2181 +++
2182 ** Regular expressions now support intervals \{n,m\} as well as
2183 Perl's shy-groups \(?:...\) and non-greedy *? +? and ?? operators.
2184
2185 +++
2186 ** The optional argument BUFFER of function file-local-copy has been
2187 removed since it wasn't used by anything.
2188
2189 +++
2190 ** The file name argument of function `file-locked-p' is now required
2191 instead of being optional.
2192
2193 +++
2194 ** The new built-in error `text-read-only' is signaled when trying to
2195 modify read-only text.
2196
2197 +++
2198 ** New functions and variables for locales.
2199
2200 The new variable `locale-coding-system' specifies how to encode and
2201 decode strings passed to low-level message functions like strerror and
2202 time functions like strftime. The new variables
2203 `system-messages-locale' and `system-time-locale' give the system
2204 locales to be used when invoking these two types of functions.
2205
2206 The new function `set-locale-environment' sets the language
2207 environment, preferred coding system, and locale coding system from
2208 the system locale as specified by the LC_ALL, LC_CTYPE, and LANG
2209 environment variables. Normally, it is invoked during startup and need
2210 not be invoked thereafter. It uses the new variables
2211 `locale-language-names', `locale-charset-language-names', and
2212 `locale-preferred-coding-systems' to make its decisions.
2213
2214 +++
2215 ** syntax tables now understand nested comments.
2216 To declare a comment syntax as allowing nesting, just add an `n'
2217 modifier to either of the characters of the comment end and the comment
2218 start sequences.
2219
2220 +++
2221 ** The function `pixmap-spec-p' has been renamed `bitmap-spec-p'
2222 because `bitmap' is more in line with the usual X terminology.
2223
2224 +++
2225 ** New function `propertize'
2226
2227 The new function `propertize' can be used to conveniently construct
2228 strings with text properties.
2229
2230 - Function: propertize STRING &rest PROPERTIES
2231
2232 Value is a copy of STRING with text properties assigned as specified
2233 by PROPERTIES. PROPERTIES is a sequence of pairs PROPERTY VALUE, with
2234 PROPERTY being the name of a text property and VALUE being the
2235 specified value of that property. Example:
2236
2237 (propertize "foo" 'face 'bold 'read-only t)
2238
2239 +++
2240 ** push and pop macros.
2241
2242 Simple versions of the push and pop macros of Common Lisp
2243 are now defined in Emacs Lisp. These macros allow only symbols
2244 as the place that holds the list to be changed.
2245
2246 (push NEWELT LISTNAME) add NEWELT to the front of LISTNAME's value.
2247 (pop LISTNAME) return first elt of LISTNAME, and remove it
2248 (thus altering the value of LISTNAME).
2249
2250 ** New dolist and dotimes macros.
2251
2252 Simple versions of the dolist and dotimes macros of Common Lisp
2253 are now defined in Emacs Lisp.
2254
2255 (dolist (VAR LIST [RESULT]) BODY...)
2256 Execute body once for each element of LIST,
2257 using the variable VAR to hold the current element.
2258 Then return the value of RESULT, or nil if RESULT is omitted.
2259
2260 (dotimes (VAR COUNT [RESULT]) BODY...)
2261 Execute BODY with VAR bound to successive integers running from 0,
2262 inclusive, to COUNT, exclusive.
2263 Then return the value of RESULT, or nil if RESULT is omitted.
2264
2265 +++
2266 ** Regular expressions now support Posix character classes such
2267 as [:alpha:], [:space:] and so on.
2268
2269 [:digit:] matches 0 through 9
2270 [:cntrl:] matches ASCII control characters
2271 [:xdigit:] matches 0 through 9, a through f and A through F.
2272 [:blank:] matches space and tab only
2273 [:graph:] matches graphic characters--everything except ASCII control chars,
2274 space, and DEL.
2275 [:print:] matches printing characters--everything except ASCII control chars
2276 and DEL.
2277 [:alnum:] matches letters and digits.
2278 (But at present, for multibyte characters,
2279 it matches anything that has word syntax.)
2280 [:alpha:] matches letters.
2281 (But at present, for multibyte characters,
2282 it matches anything that has word syntax.)
2283 [:ascii:] matches ASCII (unibyte) characters.
2284 [:nonascii:] matches non-ASCII (multibyte) characters.
2285 [:lower:] matches anything lower-case.
2286 [:punct:] matches punctuation.
2287 (But at present, for multibyte characters,
2288 it matches anything that has non-word syntax.)
2289 [:space:] matches anything that has whitespace syntax.
2290 [:upper:] matches anything upper-case.
2291 [:word:] matches anything that has word syntax.
2292
2293 +++
2294 ** Emacs now has built-in hash tables.
2295
2296 The following functions are defined for hash tables:
2297
2298 - Function: make-hash-table ARGS
2299
2300 The argument list ARGS consists of keyword/argument pairs. All arguments
2301 are optional. The following arguments are defined:
2302
2303 :test TEST
2304
2305 TEST must be a symbol specifying how to compare keys. Default is `eql'.
2306 Predefined are `eq', `eql' and `equal'. If TEST is not predefined,
2307 it must have been defined with `define-hash-table-test'.
2308
2309 :size SIZE
2310
2311 SIZE must be an integer > 0 giving a hint to the implementation how
2312 many elements will be put in the hash table. Default size is 65.
2313
2314 :rehash-size REHASH-SIZE
2315
2316 REHASH-SIZE specifies by how much to grow a hash table once it becomes
2317 full. If REHASH-SIZE is an integer, add that to the hash table's old
2318 size to get the new size. Otherwise, REHASH-SIZE must be a float >
2319 1.0, and the new size is computed by multiplying REHASH-SIZE with the
2320 old size. Default rehash size is 1.5.
2321
2322 :rehash-threshold THRESHOLD
2323
2324 THRESHOLD must be a float > 0 and <= 1.0 specifying when to resize the
2325 hash table. It is resized when the ratio of (number of entries) /
2326 (size of hash table) is >= THRESHOLD. Default threshold is 0.8.
2327
2328 :weakness WEAK
2329
2330 WEAK must be either nil, one of the symbols `key, `value',
2331 `key-or-value', `key-and-value', or t, meaning the same as
2332 `key-and-value'. Entries are removed from weak tables during garbage
2333 collection if their key and/or value are not referenced elsewhere
2334 outside of the hash table. Default are non-weak hash tables.
2335
2336 - Function: makehash &optional TEST
2337
2338 Similar to make-hash-table, but only TEST can be specified.
2339
2340 - Function: hash-table-p TABLE
2341
2342 Returns non-nil if TABLE is a hash table object.
2343
2344 - Function: copy-hash-table TABLE
2345
2346 Returns a copy of TABLE. Only the table itself is copied, keys and
2347 values are shared.
2348
2349 - Function: hash-table-count TABLE
2350
2351 Returns the number of entries in TABLE.
2352
2353 - Function: hash-table-rehash-size TABLE
2354
2355 Returns the rehash size of TABLE.
2356
2357 - Function: hash-table-rehash-threshold TABLE
2358
2359 Returns the rehash threshold of TABLE.
2360
2361 - Function: hash-table-rehash-size TABLE
2362
2363 Returns the size of TABLE.
2364
2365 - Function: hash-table-test TABLE
2366
2367 Returns the test TABLE uses to compare keys.
2368
2369 - Function: hash-table-weakness TABLE
2370
2371 Returns the weakness specified for TABLE.
2372
2373 - Function: clrhash TABLE
2374
2375 Clear TABLE.
2376
2377 - Function: gethash KEY TABLE &optional DEFAULT
2378
2379 Look up KEY in TABLE and return its associated VALUE or DEFAULT if
2380 not found.
2381
2382 - Function: puthash KEY VALUE TABLE
2383
2384 Associate KEY with VALUE in TABLE. If KEY is already associated with
2385 another value, replace the old value with VALUE.
2386
2387 - Function: remhash KEY TABLE
2388
2389 Remove KEY from TABLE if it is there.
2390
2391 - Function: maphash FUNCTION TABLE
2392
2393 Call FUNCTION for all elements in TABLE. FUNCTION must take two
2394 arguments KEY and VALUE.
2395
2396 - Function: sxhash OBJ
2397
2398 Return a hash code for Lisp object OBJ.
2399
2400 - Function: define-hash-table-test NAME TEST-FN HASH-FN
2401
2402 Define a new hash table test named NAME. If NAME is specified as
2403 a test in `make-hash-table', the table created will use TEST-FN for
2404 comparing keys, and HASH-FN to compute hash codes for keys. Test
2405 and hash function are stored as symbol property `hash-table-test'
2406 of NAME with a value of (TEST-FN HASH-FN).
2407
2408 TEST-FN must take two arguments and return non-nil if they are the same.
2409
2410 HASH-FN must take one argument and return an integer that is the hash
2411 code of the argument. The function should use the whole range of
2412 integer values for hash code computation, including negative integers.
2413
2414 Example: The following creates a hash table whose keys are supposed to
2415 be strings that are compared case-insensitively.
2416
2417 (defun case-fold-string= (a b)
2418 (compare-strings a nil nil b nil nil t))
2419
2420 (defun case-fold-string-hash (a)
2421 (sxhash (upcase a)))
2422
2423 (define-hash-table-test 'case-fold 'case-fold-string=
2424 'case-fold-string-hash))
2425
2426 (make-hash-table :test 'case-fold)
2427
2428 +++
2429 ** The Lisp reader handles circular structure.
2430
2431 It now works to use the #N= and #N# constructs to represent
2432 circular structures. For example, #1=(a . #1#) represents
2433 a cons cell which is its own cdr.
2434
2435 +++
2436 ** The Lisp printer handles circular structure.
2437
2438 If you bind print-circle to a non-nil value, the Lisp printer outputs
2439 #N= and #N# constructs to represent circular and shared structure.
2440
2441 +++
2442 ** If the second argument to `move-to-column' is anything but nil or
2443 t, that means replace a tab with spaces if necessary to reach the
2444 specified column, but do not add spaces at the end of the line if it
2445 is too short to reach that column.
2446
2447 +++
2448 ** perform-replace has a new feature: the REPLACEMENTS argument may
2449 now be a cons cell (FUNCTION . DATA). This means to call FUNCTION
2450 after each match to get the replacement text. FUNCTION is called with
2451 two arguments: DATA, and the number of replacements already made.
2452
2453 If the FROM-STRING contains any upper-case letters,
2454 perform-replace also turns off `case-fold-search' temporarily
2455 and inserts the replacement text without altering case in it.
2456
2457 +++
2458 ** The function buffer-size now accepts an optional argument
2459 to specify which buffer to return the size of.
2460
2461 +++
2462 ** The calendar motion commands now run the normal hook
2463 calendar-move-hook after moving point.
2464
2465 +++
2466 ** The new variable small-temporary-file-directory specifies a
2467 directory to use for creating temporary files that are likely to be
2468 small. (Certain Emacs features use this directory.) If
2469 small-temporary-file-directory is nil, they use
2470 temporary-file-directory instead.
2471
2472 +++
2473 ** The variable `inhibit-modification-hooks', if non-nil, inhibits all
2474 the hooks that track changes in the buffer. This affects
2475 `before-change-functions' and `after-change-functions', as well as
2476 hooks attached to text properties and overlay properties.
2477
2478 +++
2479 ** assoc-delete-all is a new function that deletes all the
2480 elements of an alist which have a particular value as the car.
2481
2482 +++
2483 ** make-temp-file provides a more reliable way to create a temporary file.
2484
2485 make-temp-file is used like make-temp-name, except that it actually
2486 creates the file before it returns. This prevents a timing error,
2487 ensuring that no other job can use the same name for a temporary file.
2488
2489 +++
2490 ** New exclusive-open feature in `write-region'
2491
2492 The optional seventh arg is now called MUSTBENEW. If non-nil, it insists
2493 on a check for an existing file with the same name. If MUSTBENEW
2494 is `excl', that means to get an error if the file already exists;
2495 never overwrite. If MUSTBENEW is neither nil nor `excl', that means
2496 ask for confirmation before overwriting, but do go ahead and
2497 overwrite the file if the user gives confirmation.
2498
2499 If the MUSTBENEW argument in `write-region' is `excl',
2500 that means to use a special feature in the `open' system call
2501 to get an error if the file exists at that time.
2502 The error reported is `file-already-exists'.
2503
2504 +++
2505 ** Function `format' now handles text properties.
2506
2507 Text properties of the format string are applied to the result string.
2508 If the result string is longer than the format string, text properties
2509 ending at the end of the format string are extended to the end of the
2510 result string.
2511
2512 Text properties from string arguments are applied to the result
2513 string where arguments appear in the result string.
2514
2515 Example:
2516
2517 (let ((s1 "hello, %s")
2518 (s2 "world"))
2519 (put-text-property 0 (length s1) 'face 'bold s1)
2520 (put-text-property 0 (length s2) 'face 'italic s2)
2521 (format s1 s2))
2522
2523 results in a bold-face string with an italic `world' at the end.
2524
2525 +++
2526 ** Messages can now be displayed with text properties.
2527
2528 Text properties are handled as described above for function `format'.
2529 The following example displays a bold-face message with an italic
2530 argument in it.
2531
2532 (let ((msg "hello, %s!")
2533 (arg "world"))
2534 (put-text-property 0 (length msg) 'face 'bold msg)
2535 (put-text-property 0 (length arg) 'face 'italic arg)
2536 (message msg arg))
2537
2538 +++
2539 ** Sound support
2540
2541 Emacs supports playing sound files on GNU/Linux and the free BSDs
2542 (Voxware driver and native BSD driver, aka as Luigi's driver).
2543
2544 Currently supported file formats are RIFF-WAVE (*.wav) and Sun Audio
2545 (*.au). You must configure Emacs with the option `--with-sound=yes'
2546 to enable sound support.
2547
2548 Sound files can be played by calling (play-sound SOUND). SOUND is a
2549 list of the form `(sound PROPERTY...)'. The function is only defined
2550 when sound support is present for the system on which Emacs runs. The
2551 functions runs `play-sound-functions' with one argument which is the
2552 sound to play, before playing the sound.
2553
2554 The following sound properties are supported:
2555
2556 - `:file FILE'
2557
2558 FILE is a file name. If FILE isn't an absolute name, it will be
2559 searched relative to `data-directory'.
2560
2561 - `:data DATA'
2562
2563 DATA is a string containing sound data. Either :file or :data
2564 may be present, but not both.
2565
2566 - `:volume VOLUME'
2567
2568 VOLUME must be an integer in the range 0..100 or a float in the range
2569 0..1. This property is optional.
2570
2571 Other properties are ignored.
2572
2573 ** `multimedia' is a new Finder keyword and Custom group.
2574
2575 ** keywordp is a new predicate to test efficiently for an object being
2576 a keyword symbol.
2577
2578 ** Changes to garbage collection
2579
2580 *** The function garbage-collect now additionally returns the number
2581 of live and free strings.
2582
2583 *** There is a new variable `strings-consed' holding the number of
2584 strings that have been consed so far.
2585
2586 \f
2587 * Lisp-level Display features added after release 2.6 of the Emacs
2588 Lisp Manual
2589
2590 *** On window systems, `glyph-table' is no longer used.
2591
2592 +++
2593 ** Help strings in menu items are now used to provide `help-echo' text.
2594
2595 ** The function `image-size' can be used to determine the size of an
2596 image.
2597
2598 - Function: image-size SPEC &optional PIXELS FRAME
2599
2600 Return the size of an image as a pair (WIDTH . HEIGHT).
2601
2602 SPEC is an image specification. PIXELS non-nil means return sizes
2603 measured in pixels, otherwise return sizes measured in canonical
2604 character units (fractions of the width/height of the frame's default
2605 font). FRAME is the frame on which the image will be displayed.
2606 FRAME nil or omitted means use the selected frame.
2607
2608 ** The function `image-mask-p' can be used to determine if an image
2609 has a mask bitmap.
2610
2611 - Function: image-mask-p SPEC &optional FRAME
2612
2613 Return t if image SPEC has a mask bitmap.
2614 FRAME is the frame on which the image will be displayed. FRAME nil
2615 or omitted means use the selected frame.
2616
2617 +++
2618 ** The function `find-image' can be used to find a usable image
2619 satisfying one of a list of specifications.
2620
2621 +++
2622 ** The STRING argument of `put-image' and `insert-image' is now
2623 optional.
2624
2625 +++
2626 ** Image specifications may contain the property `:ascent center' (see
2627 below).
2628
2629 \f
2630 * New Lisp-level Display features in Emacs 21.1
2631
2632 Note that +++ before an item means the Lisp manual has been updated.
2633 --- means that I have decided it does not need to be in the Lisp manual.
2634 When you add a new item, please add it without either +++ or ---
2635 so I will know I still need to look at it -- rms.
2636
2637 ** The function tty-suppress-bold-inverse-default-colors can be used
2638 to make Emacs avoid displaying text with bold black foreground on TTYs.
2639
2640 Some terminals, notably PC consoles, emulate bold text by displaying
2641 text in brighter colors. On such a console, a bold black foreground
2642 is displayed in a gray color. If this turns out to be hard to read on
2643 your monitor---the problem occurred with the mode line on
2644 laptops---you can instruct Emacs to ignore the text's boldness, and to
2645 just display it black instead.
2646
2647 This situation can't be detected automatically. You will have to put
2648 a line like
2649
2650 (tty-suppress-bold-inverse-default-colors t)
2651
2652 in your `.emacs'.
2653
2654 ** New face implementation.
2655
2656 Emacs faces have been reimplemented from scratch. They don't use XLFD
2657 font names anymore and face merging now works as expected.
2658
2659 +++
2660 *** New faces.
2661
2662 Each face can specify the following display attributes:
2663
2664 1. Font family or fontset alias name.
2665
2666 2. Relative proportionate width, aka character set width or set
2667 width (swidth), e.g. `semi-compressed'.
2668
2669 3. Font height in 1/10pt
2670
2671 4. Font weight, e.g. `bold'.
2672
2673 5. Font slant, e.g. `italic'.
2674
2675 6. Foreground color.
2676
2677 7. Background color.
2678
2679 8. Whether or not characters should be underlined, and in what color.
2680
2681 9. Whether or not characters should be displayed in inverse video.
2682
2683 10. A background stipple, a bitmap.
2684
2685 11. Whether or not characters should be overlined, and in what color.
2686
2687 12. Whether or not characters should be strike-through, and in what
2688 color.
2689
2690 13. Whether or not a box should be drawn around characters, its
2691 color, the width of the box lines, and 3D appearance.
2692
2693 Faces are frame-local by nature because Emacs allows to define the
2694 same named face (face names are symbols) differently for different
2695 frames. Each frame has an alist of face definitions for all named
2696 faces. The value of a named face in such an alist is a Lisp vector
2697 with the symbol `face' in slot 0, and a slot for each each of the face
2698 attributes mentioned above.
2699
2700 There is also a global face alist `face-new-frame-defaults'. Face
2701 definitions from this list are used to initialize faces of newly
2702 created frames.
2703
2704 A face doesn't have to specify all attributes. Those not specified
2705 have a nil value. Faces specifying all attributes are called
2706 `fully-specified'.
2707
2708 +++
2709 *** Face merging.
2710
2711 The display style of a given character in the text is determined by
2712 combining several faces. This process is called `face merging'. Any
2713 aspect of the display style that isn't specified by overlays or text
2714 properties is taken from the `default' face. Since it is made sure
2715 that the default face is always fully-specified, face merging always
2716 results in a fully-specified face.
2717
2718 +++
2719 *** Face realization.
2720
2721 After all face attributes for a character have been determined by
2722 merging faces of that character, that face is `realized'. The
2723 realization process maps face attributes to what is physically
2724 available on the system where Emacs runs. The result is a `realized
2725 face' in form of an internal structure which is stored in the face
2726 cache of the frame on which it was realized.
2727
2728 Face realization is done in the context of the charset of the
2729 character to display because different fonts and encodings are used
2730 for different charsets. In other words, for characters of different
2731 charsets, different realized faces are needed to display them.
2732
2733 Except for composite characters, faces are always realized for a
2734 specific character set and contain a specific font, even if the face
2735 being realized specifies a fontset. The reason is that the result of
2736 the new font selection stage is better than what can be done with
2737 statically defined font name patterns in fontsets.
2738
2739 In unibyte text, Emacs' charsets aren't applicable; function
2740 `char-charset' reports ASCII for all characters, including those >
2741 0x7f. The X registry and encoding of fonts to use is determined from
2742 the variable `face-default-registry' in this case. The variable is
2743 initialized at Emacs startup time from the font the user specified for
2744 Emacs.
2745
2746 Currently all unibyte text, i.e. all buffers with
2747 `enable-multibyte-characters' nil are displayed with fonts of the same
2748 registry and encoding `face-default-registry'. This is consistent
2749 with the fact that languages can also be set globally, only.
2750
2751 ++++
2752 **** Clearing face caches.
2753
2754 The Lisp function `clear-face-cache' can be called to clear face caches
2755 on all frames. If called with a non-nil argument, it will also unload
2756 unused fonts.
2757
2758 +++
2759 *** Font selection.
2760
2761 Font selection tries to find the best available matching font for a
2762 given (charset, face) combination. This is done slightly differently
2763 for faces specifying a fontset, or a font family name.
2764
2765 If the face specifies a fontset name, that fontset determines a
2766 pattern for fonts of the given charset. If the face specifies a font
2767 family, a font pattern is constructed. Charset symbols have a
2768 property `x-charset-registry' for that purpose that maps a charset to
2769 an XLFD registry and encoding in the font pattern constructed.
2770
2771 Available fonts on the system on which Emacs runs are then matched
2772 against the font pattern. The result of font selection is the best
2773 match for the given face attributes in this font list.
2774
2775 Font selection can be influenced by the user.
2776
2777 The user can specify the relative importance he gives the face
2778 attributes width, height, weight, and slant by setting
2779 face-font-selection-order (faces.el) to a list of face attribute
2780 names. The default is (:width :height :weight :slant), and means
2781 that font selection first tries to find a good match for the font
2782 width specified by a face, then---within fonts with that width---tries
2783 to find a best match for the specified font height, etc.
2784
2785 Setting `face-alternative-font-family-alist' allows the user to
2786 specify alternative font families to try if a family specified by a
2787 face doesn't exist.
2788
2789 +++
2790 **** Scalable fonts
2791
2792 Emacs can make use of scalable fonts but doesn't do so by default,
2793 since the use of too many or too big scalable fonts may crash XFree86
2794 servers.
2795
2796 To enable scalable font use, set the variable
2797 `scalable-fonts-allowed'. A value of nil, the default, means never use
2798 scalable fonts. A value of t means any scalable font may be used.
2799 Otherwise, the value must be a list of regular expressions. A
2800 scalable font may then be used if it matches a regular expression from
2801 that list. Example:
2802
2803 (setq scalable-fonts-allowed '("muleindian-2$"))
2804
2805 allows the use of scalable fonts with registry `muleindian-2'.
2806
2807 +++
2808 *** Functions and variables related to font selection.
2809
2810 - Function: x-family-fonts &optional FAMILY FRAME
2811
2812 Return a list of available fonts of family FAMILY on FRAME. If FAMILY
2813 is omitted or nil, list all families. Otherwise, FAMILY must be a
2814 string, possibly containing wildcards `?' and `*'.
2815
2816 If FRAME is omitted or nil, use the selected frame. Each element of
2817 the result is a vector [FAMILY WIDTH POINT-SIZE WEIGHT SLANT FIXED-P
2818 FULL REGISTRY-AND-ENCODING]. FAMILY is the font family name.
2819 POINT-SIZE is the size of the font in 1/10 pt. WIDTH, WEIGHT, and
2820 SLANT are symbols describing the width, weight and slant of the font.
2821 These symbols are the same as for face attributes. FIXED-P is non-nil
2822 if the font is fixed-pitch. FULL is the full name of the font, and
2823 REGISTRY-AND-ENCODING is a string giving the registry and encoding of
2824 the font. The result list is sorted according to the current setting
2825 of the face font sort order.
2826
2827 - Function: x-font-family-list
2828
2829 Return a list of available font families on FRAME. If FRAME is
2830 omitted or nil, use the selected frame. Value is a list of conses
2831 (FAMILY . FIXED-P) where FAMILY is a font family, and FIXED-P is
2832 non-nil if fonts of that family are fixed-pitch.
2833
2834 - Variable: font-list-limit
2835
2836 Limit for font matching. If an integer > 0, font matching functions
2837 won't load more than that number of fonts when searching for a
2838 matching font. The default is currently 100.
2839
2840 +++
2841 *** Setting face attributes.
2842
2843 For the most part, the new face implementation is interface-compatible
2844 with the old one. Old face attribute related functions are now
2845 implemented in terms of the new functions `set-face-attribute' and
2846 `face-attribute'.
2847
2848 Face attributes are identified by their names which are keyword
2849 symbols. All attributes can be set to `unspecified'.
2850
2851 The following attributes are recognized:
2852
2853 `:family'
2854
2855 VALUE must be a string specifying the font family, e.g. ``courier'',
2856 or a fontset alias name. If a font family is specified, wild-cards `*'
2857 and `?' are allowed.
2858
2859 `:width'
2860
2861 VALUE specifies the relative proportionate width of the font to use.
2862 It must be one of the symbols `ultra-condensed', `extra-condensed',
2863 `condensed', `semi-condensed', `normal', `semi-expanded', `expanded',
2864 `extra-expanded', or `ultra-expanded'.
2865
2866 `:height'
2867
2868 VALUE must be either an integer specifying the height of the font to use
2869 in 1/10 pt, a floating point number specifying the amount by which to
2870 scale any underlying face, or a function, which is called with the old
2871 height (from the underlying face), and should return the new height.
2872
2873 `:weight'
2874
2875 VALUE specifies the weight of the font to use. It must be one of the
2876 symbols `ultra-bold', `extra-bold', `bold', `semi-bold', `normal',
2877 `semi-light', `light', `extra-light', `ultra-light'.
2878
2879 `:slant'
2880
2881 VALUE specifies the slant of the font to use. It must be one of the
2882 symbols `italic', `oblique', `normal', `reverse-italic', or
2883 `reverse-oblique'.
2884
2885 `:foreground', `:background'
2886
2887 VALUE must be a color name, a string.
2888
2889 `:underline'
2890
2891 VALUE specifies whether characters in FACE should be underlined. If
2892 VALUE is t, underline with foreground color of the face. If VALUE is
2893 a string, underline with that color. If VALUE is nil, explicitly
2894 don't underline.
2895
2896 `:overline'
2897
2898 VALUE specifies whether characters in FACE should be overlined. If
2899 VALUE is t, overline with foreground color of the face. If VALUE is a
2900 string, overline with that color. If VALUE is nil, explicitly don't
2901 overline.
2902
2903 `:strike-through'
2904
2905 VALUE specifies whether characters in FACE should be drawn with a line
2906 striking through them. If VALUE is t, use the foreground color of the
2907 face. If VALUE is a string, strike-through with that color. If VALUE
2908 is nil, explicitly don't strike through.
2909
2910 `:box'
2911
2912 VALUE specifies whether characters in FACE should have a box drawn
2913 around them. If VALUE is nil, explicitly don't draw boxes. If
2914 VALUE is t, draw a box with lines of width 1 in the foreground color
2915 of the face. If VALUE is a string, the string must be a color name,
2916 and the box is drawn in that color with a line width of 1. Otherwise,
2917 VALUE must be a property list of the form `(:line-width WIDTH
2918 :color COLOR :style STYLE)'. If a keyword/value pair is missing from
2919 the property list, a default value will be used for the value, as
2920 specified below. WIDTH specifies the width of the lines to draw; it
2921 defaults to 1. COLOR is the name of the color to draw in, default is
2922 the foreground color of the face for simple boxes, and the background
2923 color of the face for 3D boxes. STYLE specifies whether a 3D box
2924 should be draw. If STYLE is `released-button', draw a box looking
2925 like a released 3D button. If STYLE is `pressed-button' draw a box
2926 that appears like a pressed button. If STYLE is nil, the default if
2927 the property list doesn't contain a style specification, draw a 2D
2928 box.
2929
2930 `:inverse-video'
2931
2932 VALUE specifies whether characters in FACE should be displayed in
2933 inverse video. VALUE must be one of t or nil.
2934
2935 `:stipple'
2936
2937 If VALUE is a string, it must be the name of a file of pixmap data.
2938 The directories listed in the `x-bitmap-file-path' variable are
2939 searched. Alternatively, VALUE may be a list of the form (WIDTH
2940 HEIGHT DATA) where WIDTH and HEIGHT are the size in pixels, and DATA
2941 is a string containing the raw bits of the bitmap. VALUE nil means
2942 explicitly don't use a stipple pattern.
2943
2944 For convenience, attributes `:family', `:width', `:height', `:weight',
2945 and `:slant' may also be set in one step from an X font name:
2946
2947 `:font'
2948
2949 Set font-related face attributes from VALUE. VALUE must be a valid
2950 XLFD font name. If it is a font name pattern, the first matching font
2951 is used--this is for compatibility with the behavior of previous
2952 versions of Emacs.
2953
2954 For compatibility with Emacs 20, keywords `:bold' and `:italic' can
2955 be used to specify that a bold or italic font should be used. VALUE
2956 must be t or nil in that case. A value of `unspecified' is not allowed."
2957
2958 Please see also the documentation of `set-face-attribute' and
2959 `defface'.
2960
2961 `:inherit'
2962
2963 VALUE is the name of a face from which to inherit attributes, or a list
2964 of face names. Attributes from inherited faces are merged into the face
2965 like an underlying face would be, with higher priority than underlying faces.
2966
2967 *** Face attributes and X resources
2968
2969 The following X resource names can be used to set face attributes
2970 from X resources:
2971
2972 Face attribute X resource class
2973 -----------------------------------------------------------------------
2974 :family attributeFamily . Face.AttributeFamily
2975 :width attributeWidth Face.AttributeWidth
2976 :height attributeHeight Face.AttributeHeight
2977 :weight attributeWeight Face.AttributeWeight
2978 :slant attributeSlant Face.AttributeSlant
2979 foreground attributeForeground Face.AttributeForeground
2980 :background attributeBackground . Face.AttributeBackground
2981 :overline attributeOverline Face.AttributeOverline
2982 :strike-through attributeStrikeThrough Face.AttributeStrikeThrough
2983 :box attributeBox Face.AttributeBox
2984 :underline attributeUnderline Face.AttributeUnderline
2985 :inverse-video attributeInverse Face.AttributeInverse
2986 :stipple attributeStipple Face.AttributeStipple
2987 or attributeBackgroundPixmap
2988 Face.AttributeBackgroundPixmap
2989 :font attributeFont Face.AttributeFont
2990 :bold attributeBold Face.AttributeBold
2991 :italic attributeItalic . Face.AttributeItalic
2992 :font attributeFont Face.AttributeFont
2993
2994 +++
2995 *** Text property `face'.
2996
2997 The value of the `face' text property can now be a single face
2998 specification or a list of such specifications. Each face
2999 specification can be
3000
3001 1. A symbol or string naming a Lisp face.
3002
3003 2. A property list of the form (KEYWORD VALUE ...) where each
3004 KEYWORD is a face attribute name, and VALUE is an appropriate value
3005 for that attribute. Please see the doc string of `set-face-attribute'
3006 for face attribute names.
3007
3008 3. Conses of the form (FOREGROUND-COLOR . COLOR) or
3009 (BACKGROUND-COLOR . COLOR) where COLOR is a color name. This is
3010 for compatibility with previous Emacs versions.
3011
3012 +++
3013 ** Support functions for colors on text-only terminals.
3014
3015 The function `tty-color-define' can be used to define colors for use
3016 on TTY and MSDOS frames. It maps a color name to a color number on
3017 the terminal. Emacs defines a couple of common color mappings by
3018 default. You can get defined colors with a call to
3019 `defined-colors'. The function `tty-color-clear' can be
3020 used to clear the mapping table.
3021
3022 ** Unified support for colors independent of frame type.
3023
3024 The new functions `defined-colors', `color-defined-p', `color-values',
3025 and `display-color-p' work for any type of frame. On frames whose
3026 type is neither x nor w32, these functions transparently map X-style
3027 color specifications to the closest colors supported by the frame
3028 display. Lisp programs should use these new functions instead of the
3029 old `x-defined-colors', `x-color-defined-p', `x-color-values', and
3030 `x-display-color-p'. (The old function names are still available for
3031 compatibility; they are now aliases of the new names.) Lisp programs
3032 should no more look at the value of the variable window-system to
3033 modify their color-related behavior.
3034
3035 The primitives `color-gray-p' and `color-supported-p' also work for
3036 any frame type.
3037
3038 ** Platform-independent functions to describe display capabilities.
3039
3040 The new functions `display-mouse-p', `display-popup-menus-p',
3041 `display-graphic-p', `display-selections-p', `display-screens',
3042 `display-pixel-width', `display-pixel-height', `display-mm-width',
3043 `display-mm-height', `display-backing-store', `display-save-under',
3044 `display-planes', `display-color-cells', `display-visual-class', and
3045 `display-grayscale-p' describe the basic capabilities of a particular
3046 display. Lisp programs should call these functions instead of testing
3047 the value of the variables `window-system' or `system-type', or calling
3048 platform-specific functions such as `x-display-pixel-width'.
3049
3050 +++
3051 ** The minibuffer prompt is now actually inserted in the minibuffer.
3052
3053 This makes it possible to scroll through the prompt, if you want to.
3054
3055 The function minubuffer-prompt-end returns the current position of the
3056 end of the minibuffer prompt, if the minibuffer is current.
3057 Otherwise, it returns zero.
3058
3059 ** New `field' abstraction in buffers.
3060
3061 There is now code to support an abstraction called `fields' in emacs
3062 buffers. A field is a contiguous region of text with the same `field'
3063 property (which can be a text property or an overlay).
3064
3065 Many emacs functions, such as forward-word, forward-sentence,
3066 forward-paragraph, beginning-of-line, etc., stop moving when they come
3067 to the boundary between fields; beginning-of-line and end-of-line will
3068 not let the point move past the field boundary, but other movement
3069 commands continue into the next field if repeated. Stopping at field
3070 boundaries can be suppressed programmatically by binding
3071 `inhibit-field-text-motion' to a non-nil value around calls to these
3072 functions.
3073
3074 Now that the minibuffer prompt is inserted into the minibuffer, it is in
3075 a separate field from the user-input part of the buffer, so that common
3076 editing commands treat the user's text separately from the prompt.
3077
3078 The following functions are defined for operating on fields:
3079
3080 - Function: constrain-to-field NEW-POS OLD-POS &optional ESCAPE-FROM-EDGE ONLY-IN-LINE INHIBIT-CAPTURE-PROPERTY
3081
3082 Return the position closest to NEW-POS that is in the same field as OLD-POS.
3083
3084 A field is a region of text with the same `field' property.
3085 If NEW-POS is nil, then the current point is used instead, and set to the
3086 constrained position if that is is different.
3087
3088 If OLD-POS is at the boundary of two fields, then the allowable
3089 positions for NEW-POS depends on the value of the optional argument
3090 ESCAPE-FROM-EDGE: If ESCAPE-FROM-EDGE is nil, then NEW-POS is
3091 constrained to the field that has the same `field' char-property
3092 as any new characters inserted at OLD-POS, whereas if ESCAPE-FROM-EDGE
3093 is non-nil, NEW-POS is constrained to the union of the two adjacent
3094 fields. Additionally, if two fields are separated by another field with
3095 the special value `boundary', then any point within this special field is
3096 also considered to be `on the boundary'.
3097
3098 If the optional argument ONLY-IN-LINE is non-nil and constraining
3099 NEW-POS would move it to a different line, NEW-POS is returned
3100 unconstrained. This useful for commands that move by line, like
3101 C-n or C-a, which should generally respect field boundaries
3102 only in the case where they can still move to the right line.
3103
3104 If the optional argument INHIBIT-CAPTURE-PROPERTY is non-nil, and OLD-POS has
3105 a non-nil property of that name, then any field boundaries are ignored.
3106
3107 Field boundaries are not noticed if `inhibit-field-text-motion' is non-nil.
3108
3109 - Function: delete-field &optional POS
3110
3111 Delete the field surrounding POS.
3112 A field is a region of text with the same `field' property.
3113 If POS is nil, the value of point is used for POS.
3114
3115 - Function: field-beginning &optional POS ESCAPE-FROM-EDGE
3116
3117 Return the beginning of the field surrounding POS.
3118 A field is a region of text with the same `field' property.
3119 If POS is nil, the value of point is used for POS.
3120 If ESCAPE-FROM-EDGE is non-nil and POS is at the beginning of its
3121 field, then the beginning of the *previous* field is returned.
3122
3123 - Function: field-end &optional POS ESCAPE-FROM-EDGE
3124
3125 Return the end of the field surrounding POS.
3126 A field is a region of text with the same `field' property.
3127 If POS is nil, the value of point is used for POS.
3128 If ESCAPE-FROM-EDGE is non-nil and POS is at the end of its field,
3129 then the end of the *following* field is returned.
3130
3131 - Function: field-string &optional POS
3132
3133 Return the contents of the field surrounding POS as a string.
3134 A field is a region of text with the same `field' property.
3135 If POS is nil, the value of point is used for POS.
3136
3137 - Function: field-string-no-properties &optional POS
3138
3139 Return the contents of the field around POS, without text-properties.
3140 A field is a region of text with the same `field' property.
3141 If POS is nil, the value of point is used for POS.
3142
3143 +++
3144 ** Image support.
3145
3146 Emacs can now display images. Images are inserted into text by giving
3147 strings or buffer text a `display' text property containing one of
3148 (AREA IMAGE) or IMAGE. The display of the `display' property value
3149 replaces the display of the characters having that property.
3150
3151 If the property value has the form (AREA IMAGE), AREA must be one of
3152 `(margin left-margin)', `(margin right-margin)' or `(margin nil)'. If
3153 AREA is `(margin nil)', IMAGE will be displayed in the text area of a
3154 window, otherwise it will be displayed in the left or right marginal
3155 area.
3156
3157 IMAGE is an image specification.
3158
3159 *** Image specifications
3160
3161 Image specifications are lists of the form `(image PROPS)' where PROPS
3162 is a property list whose keys are keyword symbols. Each
3163 specifications must contain a property `:type TYPE' with TYPE being a
3164 symbol specifying the image type, e.g. `xbm'. Properties not
3165 described below are ignored.
3166
3167 The following is a list of properties all image types share.
3168
3169 `:ascent ASCENT'
3170
3171 ASCENT must be a number in the range 0..100, or the symbol `center'.
3172 If it is a number, it specifies the percentage of the image's height
3173 to use for its ascent.
3174
3175 If not specified, ASCENT defaults to the value 50 which means that the
3176 image will be centered with the base line of the row it appears in.
3177
3178 If ASCENT is `center' the image is vertically centered around a
3179 centerline which is the vertical center of text drawn at the position
3180 of the image, in the manner specified by the text properties and
3181 overlays that apply to the image.
3182
3183 `:margin MARGIN'
3184
3185 MARGIN must be a number >= 0 specifying how many pixels to put as
3186 margin around the image. Default is 0.
3187
3188 `:relief RELIEF'
3189
3190 RELIEF is analogous to the `:relief' attribute of faces. Puts a relief
3191 around an image.
3192
3193 `:algorithm ALGO'
3194
3195 Apply an image algorithm to the image before displaying it.
3196
3197 ALGO `laplace' or `emboss' means apply a Laplace or ``emboss''
3198 edge-detection algorithm to the image.
3199
3200 ALGO `(edge-detection :matrix MATRIX :color-adjust ADJUST)' means
3201 apply a general edge-detection algorithm. MATRIX must be either a
3202 nine-element list or a nine-element vector of numbers. A pixel at
3203 position x/y in the transformed image is computed from original pixels
3204 around that position. MATRIX specifies, for each pixel in the
3205 neighborhood of x/y, a factor with which that pixel will influence the
3206 transformed pixel; element 0 specifies the factor for the pixel at
3207 x-1/y-1, element 1 the factor for the pixel at x/y-1 etc. as shown
3208 below.
3209
3210 (x-1/y-1 x/y-1 x+1/y-1
3211 x-1/y x/y x+1/y
3212 x-1/y+1 x/y+1 x+1/y+1)
3213
3214 The resulting pixel is computed from the color intensity of the color
3215 resulting from summing up the RGB values of surrounding pixels,
3216 multiplied by the specified factors, and dividing that sum by the sum
3217 of the factors' absolute values.
3218
3219 Laplace edge-detection currently uses a matrix of
3220
3221 (1 0 0
3222 0 0 0
3223 9 9 -1)
3224
3225 Emboss edge-detection uses a matrix of
3226
3227 ( 2 -1 0
3228 -1 0 1
3229 0 1 -2)
3230
3231 ALGO `disabled' means transform the image so that it looks
3232 ``disabled''.
3233
3234 `:mask MASK'
3235
3236 If MASK is `heuristic' or `(heuristic BG)', build a clipping mask for
3237 the image, so that the background of a frame is visible behind the
3238 image. If BG is not specified, or if BG is t, determine the
3239 background color of the image by looking at the 4 corners of the
3240 image, assuming the most frequently occuring color from the corners is
3241 the background color of the image. Otherwise, BG must be a list `(RED
3242 GREEN BLUE)' specifying the color to assume for the background of the
3243 image.
3244
3245 If MASK is nil, remove a mask from the image, if it has one. Images
3246 in some formats include a mask which can be removed by specifying
3247 `:mask nil'.
3248
3249 `:file FILE'
3250
3251 Load image from FILE. If FILE is not absolute after expanding it,
3252 search for the image in `data-directory'. Some image types support
3253 building images from data. When this is done, no `:file' property
3254 may be present in the image specification.
3255
3256 `:data DATA'
3257
3258 Get image data from DATA. (As of this writing, this is not yet
3259 supported for image type `postscript'). Either :file or :data may be
3260 present in an image specification, but not both. All image types
3261 support strings as DATA, some types allow additional types of DATA.
3262
3263 *** Supported image types
3264
3265 **** XBM, image type `xbm'.
3266
3267 XBM images don't require an external library. Additional image
3268 properties supported are
3269
3270 `:foreground FG'
3271
3272 FG must be a string specifying the image foreground color. Default
3273 is the frame's foreground.
3274
3275 `:background FG'
3276
3277 BG must be a string specifying the image foreground color. Default is
3278 the frame's background color.
3279
3280 XBM images can be constructed from data instead of file. In this
3281 case, the image specification must contain the following properties
3282 instead of a `:file' property.
3283
3284 `:width WIDTH'
3285
3286 WIDTH specifies the width of the image in pixels.
3287
3288 `:height HEIGHT'
3289
3290 HEIGHT specifies the height of the image in pixels.
3291
3292 `:data DATA'
3293
3294 DATA must be either
3295
3296 1. a string large enough to hold the bitmap data, i.e. it must
3297 have a size >= (WIDTH + 7) / 8 * HEIGHT
3298
3299 2. a bool-vector of size >= WIDTH * HEIGHT
3300
3301 3. a vector of strings or bool-vectors, one for each line of the
3302 bitmap.
3303
3304 4. a string that's an in-memory XBM file. Neither width nor
3305 height may be specified in this case because these are defined
3306 in the file.
3307
3308 **** XPM, image type `xpm'
3309
3310 XPM images require the external library `libXpm', package
3311 `xpm-3.4k.tar.gz', version 3.4k or later. Make sure the library is
3312 found when Emacs is configured by supplying appropriate paths via
3313 `--x-includes' and `--x-libraries'.
3314
3315 Additional image properties supported are:
3316
3317 `:color-symbols SYMBOLS'
3318
3319 SYMBOLS must be a list of pairs (NAME . COLOR), with NAME being the
3320 name of color as it appears in an XPM file, and COLOR being an X color
3321 name.
3322
3323 XPM images can be built from memory instead of files. In that case,
3324 add a `:data' property instead of a `:file' property.
3325
3326 The XPM library uses libz in its implementation so that it is able
3327 to display compressed images.
3328
3329 **** PBM, image type `pbm'
3330
3331 PBM images don't require an external library. Color, gray-scale and
3332 mono images are supported. There are no additional image properties
3333 defined.
3334
3335 **** JPEG, image type `jpeg'
3336
3337 Support for JPEG images requires the external library `libjpeg',
3338 package `jpegsrc.v6a.tar.gz', or later. Additional image properties
3339 are:
3340
3341 **** TIFF, image type `tiff'
3342
3343 Support for TIFF images requires the external library `libtiff',
3344 package `tiff-v3.4-tar.gz', or later. There are no additional image
3345 properties defined.
3346
3347 **** GIF, image type `gif'
3348
3349 Support for GIF images requires the external library `libungif', package
3350 `libungif-4.1.0', or later.
3351
3352 Additional image properties supported are:
3353
3354 `:index INDEX'
3355
3356 INDEX must be an integer >= 0. Load image number INDEX from a
3357 multi-image GIF file. An error is signalled if INDEX is too large.
3358
3359 This could be used to implement limited support for animated GIFs.
3360 For example, the following function displays a multi-image GIF file
3361 at point-min in the current buffer, switching between sub-images
3362 every 0.1 seconds.
3363
3364 (defun show-anim (file max)
3365 "Display multi-image GIF file FILE which contains MAX subimages."
3366 (display-anim (current-buffer) file 0 max t))
3367
3368 (defun display-anim (buffer file idx max first-time)
3369 (when (= idx max)
3370 (setq idx 0))
3371 (let ((img (create-image file nil nil :index idx)))
3372 (save-excursion
3373 (set-buffer buffer)
3374 (goto-char (point-min))
3375 (unless first-time (delete-char 1))
3376 (insert-image img "x"))
3377 (run-with-timer 0.1 nil 'display-anim buffer file (1+ idx) max nil)))
3378
3379 **** PNG, image type `png'
3380
3381 Support for PNG images requires the external library `libpng',
3382 package `libpng-1.0.2.tar.gz', or later. There are no additional image
3383 properties defined.
3384
3385 **** Ghostscript, image type `postscript'.
3386
3387 Additional image properties supported are:
3388
3389 `:pt-width WIDTH'
3390
3391 WIDTH is width of the image in pt (1/72 inch). WIDTH must be an
3392 integer. This is a required property.
3393
3394 `:pt-height HEIGHT'
3395
3396 HEIGHT specifies the height of the image in pt (1/72 inch). HEIGHT
3397 must be a integer. This is an required property.
3398
3399 `:bounding-box BOX'
3400
3401 BOX must be a list or vector of 4 integers giving the bounding box of
3402 the PS image, analogous to the `BoundingBox' comment found in PS
3403 files. This is an required property.
3404
3405 Part of the Ghostscript interface is implemented in Lisp. See
3406 lisp/gs.el.
3407
3408 *** Lisp interface.
3409
3410 The variable `image-types' contains a list of those image types
3411 which are supported in the current configuration.
3412
3413 Images are stored in an image cache and removed from the cache when
3414 they haven't been displayed for `image-cache-eviction-delay seconds.
3415 The function `clear-image-cache' can be used to clear the image cache
3416 manually. Images in the cache are compared with `equal', i.e. all
3417 images with `equal' specifications share the same image.
3418
3419 *** Simplified image API, image.el
3420
3421 The new Lisp package image.el contains functions that simplify image
3422 creation and putting images into text. The function `create-image'
3423 can be used to create images. The macro `defimage' can be used to
3424 define an image based on available image types. The functions
3425 `put-image' and `insert-image' can be used to insert an image into a
3426 buffer.
3427
3428 +++
3429 ** Display margins.
3430
3431 Windows can now have margins which are used for special text
3432 and images.
3433
3434 To give a window margins, either set the buffer-local variables
3435 `left-margin-width' and `right-margin-width', or call
3436 `set-window-margins'. The function `window-margins' can be used to
3437 obtain the current settings. To make `left-margin-width' and
3438 `right-margin-width' take effect, you must set them before displaying
3439 the buffer in a window, or use `set-window-buffer' to force an update
3440 of the display margins.
3441
3442 You can put text in margins by giving it a `display' text property
3443 containing a pair of the form `(LOCATION . VALUE)', where LOCATION is
3444 one of `left-margin' or `right-margin' or nil. VALUE can be either a
3445 string, an image specification or a stretch specification (see later
3446 in this file).
3447
3448 +++
3449 ** Help display
3450
3451 Emacs displays short help messages in the echo area, when the mouse
3452 moves over a tool-bar item or a piece of text that has a text property
3453 `help-echo'. This feature also applies to strings in the mode line
3454 that have a `help-echo' property.
3455
3456 If the value of the `help-echo' property is a function, that function
3457 is called with three arguments WINDOW, OBJECT and POSITION. WINDOW is
3458 the window in which the help was found.
3459
3460 If OBJECT is a buffer, POS is the position in the buffer where the
3461 `help-echo' text property was found.
3462
3463 If OBJECT is an overlay, that overlay has a `help-echo' property, and
3464 POS is the position in the overlay's buffer under the mouse.
3465
3466 If OBJECT is a string (an overlay string or a string displayed with
3467 the `display' property), POS is the position in that string under the
3468 mouse.
3469
3470 If the value of the `help-echo' property is neither a function nor a
3471 string, it is evaluated to obtain a help string.
3472
3473 For tool-bar and menu-bar items, their key definition is used to
3474 determine the help to display. If their definition contains a
3475 property `:help FORM', FORM is evaluated to determine the help string.
3476 For tool-bar items without a help form, the caption of the item is
3477 used as help string.
3478
3479 The hook `show-help-function' can be set to a function that displays
3480 the help string differently. For example, enabling a tooltip window
3481 causes the help display to appear there instead of in the echo area.
3482
3483 +++
3484 ** Vertical fractional scrolling.
3485
3486 The display of text in windows can be scrolled smoothly in pixels.
3487 This is useful, for example, for making parts of large images visible.
3488
3489 The function `window-vscroll' returns the current value of vertical
3490 scrolling, a non-negative fraction of the canonical character height.
3491 The function `set-window-vscroll' can be used to set the vertical
3492 scrolling value. Here is an example of how these function might be
3493 used.
3494
3495 (global-set-key [A-down]
3496 #'(lambda ()
3497 (interactive)
3498 (set-window-vscroll (selected-window)
3499 (+ 0.5 (window-vscroll)))))
3500 (global-set-key [A-up]
3501 #'(lambda ()
3502 (interactive)
3503 (set-window-vscroll (selected-window)
3504 (- (window-vscroll) 0.5)))))
3505
3506 +++
3507 ** New hook `fontification-functions'.
3508
3509 Functions from `fontification-functions' are called from redisplay
3510 when it encounters a region of text that is not yet fontified. This
3511 variable automatically becomes buffer-local when set. Each function
3512 is called with one argument, POS.
3513
3514 At least one of the hook functions should fontify one or more
3515 characters starting at POS in the current buffer. It should mark them
3516 as fontified by giving them a non-nil value of the `fontified' text
3517 property. It may be reasonable for these functions to check for the
3518 `fontified' property and not put it back on, but they do not have to.
3519
3520 +++
3521 ** Tool bar support.
3522
3523 Emacs supports a tool bar at the top of a frame under X. The frame
3524 parameter `tool-bar-lines' (X resource "toolBar", class "ToolBar")
3525 controls how may lines to reserve for the tool bar. A zero value
3526 suppresses the tool bar. If the value is non-zero and
3527 `auto-resize-tool-bars' is non-nil the tool bar's size will be changed
3528 automatically so that all tool bar items are visible.
3529
3530 *** Tool bar item definitions
3531
3532 Tool bar items are defined using `define-key' with a prefix-key
3533 `tool-bar'. For example `(define-key global-map [tool-bar item1] ITEM)'
3534 where ITEM is a list `(menu-item CAPTION BINDING PROPS...)'.
3535
3536 CAPTION is the caption of the item, If it's not a string, it is
3537 evaluated to get a string. The caption is currently not displayed in
3538 the tool bar, but it is displayed if the item doesn't have a `:help'
3539 property (see below).
3540
3541 BINDING is the tool bar item's binding. Tool bar items with keymaps as
3542 binding are currently ignored.
3543
3544 The following properties are recognized:
3545
3546 `:enable FORM'.
3547
3548 FORM is evaluated and specifies whether the tool bar item is enabled
3549 or disabled.
3550
3551 `:visible FORM'
3552
3553 FORM is evaluated and specifies whether the tool bar item is displayed.
3554
3555 `:filter FUNCTION'
3556
3557 FUNCTION is called with one parameter, the same list BINDING in which
3558 FUNCTION is specified as the filter. The value FUNCTION returns is
3559 used instead of BINDING to display this item.
3560
3561 `:button (TYPE SELECTED)'
3562
3563 TYPE must be one of `:radio' or `:toggle'. SELECTED is evaluated
3564 and specifies whether the button is selected (pressed) or not.
3565
3566 `:image IMAGES'
3567
3568 IMAGES is either a single image specification or a vector of four
3569 image specifications. If it is a vector, this table lists the
3570 meaning of each of the four elements:
3571
3572 Index Use when item is
3573 ----------------------------------------
3574 0 enabled and selected
3575 1 enabled and deselected
3576 2 disabled and selected
3577 3 disabled and deselected
3578
3579 If IMAGE is a single image specification, a Laplace edge-detection
3580 algorithm is used on that image to draw the image in disabled state.
3581
3582 `:help HELP-STRING'.
3583
3584 Gives a help string to display for the tool bar item. This help
3585 is displayed when the mouse is moved over the item.
3586
3587 The function `toolbar-add-item' is a convenience function for adding
3588 toolbar items generally, and `tool-bar-add-item-from-menu' can be used
3589 to define a toolbar item with a binding copied from an item on the
3590 menu bar.
3591
3592 *** Tool-bar-related variables.
3593
3594 If `auto-resize-tool-bar' is non-nil, the tool bar will automatically
3595 resize to show all defined tool bar items. It will never grow larger
3596 than 1/4 of the frame's size.
3597
3598 If `auto-raise-tool-bar-buttons' is non-nil, tool bar buttons will be
3599 raised when the mouse moves over them.
3600
3601 You can add extra space between tool bar items by setting
3602 `tool-bar-button-margin' to a positive integer specifying a number of
3603 pixels. Default is 1.
3604
3605 You can change the shadow thickness of tool bar buttons by setting
3606 `tool-bar-button-relief' to an integer. Default is 3.
3607
3608 *** Tool-bar clicks with modifiers.
3609
3610 You can bind commands to clicks with control, shift, meta etc. on
3611 a tool bar item. If
3612
3613 (define-key global-map [tool-bar shell]
3614 '(menu-item "Shell" shell
3615 :image (image :type xpm :file "shell.xpm")))
3616
3617 is the original tool bar item definition, then
3618
3619 (define-key global-map [tool-bar S-shell] 'some-command)
3620
3621 makes a binding to run `some-command' for a shifted click on the same
3622 item.
3623
3624 ** Mode line changes.
3625
3626 +++
3627 *** Mouse-sensitive mode line.
3628
3629 The mode line can be made mouse-sensitive by displaying strings there
3630 that have a `local-map' text property. There are three ways to display
3631 a string with a `local-map' property in the mode line.
3632
3633 1. The mode line spec contains a variable whose string value has
3634 a `local-map' text property.
3635
3636 2. The mode line spec contains a format specifier (e.g. `%12b'), and
3637 that format specifier has a `local-map' property.
3638
3639 3. The mode line spec contains a list containing `:eval FORM'. FORM
3640 is evaluated. If the result is a string, and that string has a
3641 `local-map' property.
3642
3643 The same mechanism is used to determine the `face' and `help-echo'
3644 properties of strings in the mode line. See `bindings.el' for an
3645 example.
3646
3647 *** If a mode line element has the form `(:eval FORM)', FORM is
3648 evaluated and the result is used as mode line element.
3649
3650 +++
3651 *** You can suppress mode-line display by setting the buffer-local
3652 variable mode-line-format to nil.
3653
3654 +++
3655 *** A headerline can now be displayed at the top of a window.
3656
3657 This mode line's contents are controlled by the new variable
3658 `header-line-format' and `default-header-line-format' which are
3659 completely analogous to `mode-line-format' and
3660 `default-mode-line-format'. A value of nil means don't display a top
3661 line.
3662
3663 The appearance of top mode lines is controlled by the face
3664 `header-line'.
3665
3666 The function `coordinates-in-window-p' returns `header-line' for a
3667 position in the header-line.
3668
3669 +++
3670 ** Text property `display'
3671
3672 The `display' text property is used to insert images into text,
3673 replace text with other text, display text in marginal area, and it is
3674 also used to control other aspects of how text displays. The value of
3675 the `display' property should be a display specification, as described
3676 below, or a list or vector containing display specifications.
3677
3678 *** Replacing text, displaying text in marginal areas
3679
3680 To replace the text having the `display' property with some other
3681 text, use a display specification of the form `(LOCATION STRING)'.
3682
3683 If LOCATION is `(margin left-margin)', STRING is displayed in the left
3684 marginal area, if it is `(margin right-margin)', it is displayed in
3685 the right marginal area, and if LOCATION is `(margin nil)' STRING
3686 is displayed in the text. In the latter case you can also use the
3687 simpler form STRING as property value.
3688
3689 *** Variable width and height spaces
3690
3691 To display a space of fractional width or height, use a display
3692 specification of the form `(LOCATION STRECH)'. If LOCATION is
3693 `(margin left-margin)', the space is displayed in the left marginal
3694 area, if it is `(margin right-margin)', it is displayed in the right
3695 marginal area, and if LOCATION is `(margin nil)' the space is
3696 displayed in the text. In the latter case you can also use the
3697 simpler form STRETCH as property value.
3698
3699 The stretch specification STRETCH itself is a list of the form `(space
3700 PROPS)', where PROPS is a property list which can contain the
3701 properties described below.
3702
3703 The display of the fractional space replaces the display of the
3704 characters having the `display' property.
3705
3706 - :width WIDTH
3707
3708 Specifies that the space width should be WIDTH times the normal
3709 character width. WIDTH can be an integer or floating point number.
3710
3711 - :relative-width FACTOR
3712
3713 Specifies that the width of the stretch should be computed from the
3714 first character in a group of consecutive characters that have the
3715 same `display' property. The computation is done by multiplying the
3716 width of that character by FACTOR.
3717
3718 - :align-to HPOS
3719
3720 Specifies that the space should be wide enough to reach HPOS. The
3721 value HPOS is measured in units of the normal character width.
3722
3723 Exactly one of the above properties should be used.
3724
3725 - :height HEIGHT
3726
3727 Specifies the height of the space, as HEIGHT, measured in terms of the
3728 normal line height.
3729
3730 - :relative-height FACTOR
3731
3732 The height of the space is computed as the product of the height
3733 of the text having the `display' property and FACTOR.
3734
3735 - :ascent ASCENT
3736
3737 Specifies that ASCENT percent of the height of the stretch should be
3738 used for the ascent of the stretch, i.e. for the part above the
3739 baseline. The value of ASCENT must be a non-negative number less or
3740 equal to 100.
3741
3742 You should not use both `:height' and `:relative-height' together.
3743
3744 *** Images
3745
3746 A display specification for an image has the form `(LOCATION
3747 . IMAGE)', where IMAGE is an image specification. The image replaces,
3748 in the display, the characters having this display specification in
3749 their `display' text property. If LOCATION is `(margin left-margin)',
3750 the image will be displayed in the left marginal area, if it is
3751 `(margin right-margin)' it will be displayed in the right marginal
3752 area, and if LOCATION is `(margin nil)' the image will be displayed in
3753 the text. In the latter case you can also use the simpler form IMAGE
3754 as display specification.
3755
3756 *** Other display properties
3757
3758 - :space-width FACTOR
3759
3760 Specifies that space characters in the text having that property
3761 should be displayed FACTOR times as wide as normal; FACTOR must be an
3762 integer or float.
3763
3764 - :height HEIGHT
3765
3766 Display text having this property in a font that is smaller or larger.
3767
3768 If HEIGHT is a list of the form `(+ N)', where N is an integer, that
3769 means to use a font that is N steps larger. If HEIGHT is a list of
3770 the form `(- N)', that means to use a font that is N steps smaller. A
3771 ``step'' is defined by the set of available fonts; each size for which
3772 a font is available counts as a step.
3773
3774 If HEIGHT is a number, that means to use a font that is HEIGHT times
3775 as tall as the frame's default font.
3776
3777 If HEIGHT is a symbol, it is called as a function with the current
3778 height as argument. The function should return the new height to use.
3779
3780 Otherwise, HEIGHT is evaluated to get the new height, with the symbol
3781 `height' bound to the current specified font height.
3782
3783 - :raise FACTOR
3784
3785 FACTOR must be a number, specifying a multiple of the current
3786 font's height. If it is positive, that means to display the characters
3787 raised. If it is negative, that means to display them lower down. The
3788 amount of raising or lowering is computed without taking account of the
3789 `:height' subproperty.
3790
3791 *** Conditional display properties
3792
3793 All display specifications can be conditionalized. If a specification
3794 has the form `(:when CONDITION . SPEC)', the specification SPEC
3795 applies only when CONDITION yields a non-nil value when evaluated.
3796 During evaluattion, point is temporarily set to the end position of
3797 the text having the `display' property.
3798
3799 The normal specification consisting of SPEC only is equivalent to
3800 `(:when t SPEC)'.
3801
3802 +++
3803 ** New menu separator types.
3804
3805 Emacs now supports more than one menu separator type. Menu items with
3806 item names consisting of dashes only (including zero dashes) are
3807 treated like before. In addition, the following item names are used
3808 to specify other menu separator types.
3809
3810 - `--no-line' or `--space', or `--:space', or `--:noLine'
3811
3812 No separator lines are drawn, but a small space is inserted where the
3813 separator occurs.
3814
3815 - `--single-line' or `--:singleLine'
3816
3817 A single line in the menu's foreground color.
3818
3819 - `--double-line' or `--:doubleLine'
3820
3821 A double line in the menu's foreground color.
3822
3823 - `--single-dashed-line' or `--:singleDashedLine'
3824
3825 A single dashed line in the menu's foreground color.
3826
3827 - `--double-dashed-line' or `--:doubleDashedLine'
3828
3829 A double dashed line in the menu's foreground color.
3830
3831 - `--shadow-etched-in' or `--:shadowEtchedIn'
3832
3833 A single line with 3D sunken appearance. This is the the form
3834 displayed for item names consisting of dashes only.
3835
3836 - `--shadow-etched-out' or `--:shadowEtchedOut'
3837
3838 A single line with 3D raised appearance.
3839
3840 - `--shadow-etched-in-dash' or `--:shadowEtchedInDash'
3841
3842 A single dashed line with 3D sunken appearance.
3843
3844 - `--shadow-etched-out-dash' or `--:shadowEtchedOutDash'
3845
3846 A single dashed line with 3D raise appearance.
3847
3848 - `--shadow-double-etched-in' or `--:shadowDoubleEtchedIn'
3849
3850 Two lines with 3D sunken appearance.
3851
3852 - `--shadow-double-etched-out' or `--:shadowDoubleEtchedOut'
3853
3854 Two lines with 3D raised appearance.
3855
3856 - `--shadow-double-etched-in-dash' or `--:shadowDoubleEtchedInDash'
3857
3858 Two dashed lines with 3D sunken appearance.
3859
3860 - `--shadow-double-etched-out-dash' or `--:shadowDoubleEtchedOutDash'
3861
3862 Two dashed lines with 3D raised appearance.
3863
3864 Under LessTif/Motif, the last four separator types are displayed like
3865 the corresponding single-line separators.
3866
3867 +++
3868 ** New frame parameters for scroll bar colors.
3869
3870 The new frame parameters `scroll-bar-foreground' and
3871 `scroll-bar-background' can be used to change scroll bar colors.
3872 Their value must be either a color name, a string, or nil to specify
3873 that scroll bars should use a default color. For toolkit scroll bars,
3874 default colors are toolkit specific. For non-toolkit scroll bars, the
3875 default background is the background color of the frame, and the
3876 default foreground is black.
3877
3878 The X resource name of these parameters are `scrollBarForeground'
3879 (class ScrollBarForeground) and `scrollBarBackground' (class
3880 `ScrollBarBackground').
3881
3882 Setting these parameters overrides toolkit specific X resource
3883 settings for scroll bar colors.
3884
3885 +++
3886 ** You can set `redisplay-dont-pause' to a non-nil value to prevent
3887 display updates from being interrupted when input is pending.
3888
3889 ---
3890 ** Changing a window's width may now change its window start if it
3891 starts on a continuation line. The new window start is computed based
3892 on the window's new width, starting from the start of the continued
3893 line as the start of the screen line with the minimum distance from
3894 the original window start.
3895
3896 ---
3897 ** The variable `hscroll-step' and the functions
3898 `hscroll-point-visible' and `hscroll-window-column' have been removed
3899 now that proper horizontal scrolling is implemented.
3900
3901 +++
3902 ** Windows can now be made fixed-width and/or fixed-height.
3903
3904 A window is fixed-size if its buffer has a buffer-local variable
3905 `window-size-fixed' whose value is not nil. A value of `height' makes
3906 windows fixed-height, a value of `width' makes them fixed-width, any
3907 other non-nil value makes them both fixed-width and fixed-height.
3908
3909 The following code makes all windows displaying the current buffer
3910 fixed-width and fixed-height.
3911
3912 (set (make-local-variable 'window-size-fixed) t)
3913
3914 A call to enlarge-window on a window gives an error if that window is
3915 fixed-width and it is tried to change the window's width, or if the
3916 window is fixed-height, and it is tried to change its height. To
3917 change the size of a fixed-size window, bind `window-size-fixed'
3918 temporarily to nil, for example
3919
3920 (let ((window-size-fixed nil))
3921 (enlarge-window 10))
3922
3923 Likewise, an attempt to split a fixed-height window vertically,
3924 or a fixed-width window horizontally results in a error.
3925
3926 ** The cursor-type frame parameter is now supported on MS-DOS
3927 terminals. When Emacs starts, it by default changes the cursor shape
3928 to a solid box, as it does on Unix. The `cursor-type' frame parameter
3929 overrides this as it does on Unix, except that the bar cursor is
3930 horizontal rather than vertical (since the MS-DOS display doesn't
3931 support a vertical-bar cursor).
3932
3933
3934 ^L
3935 * Emacs 20.7 is a bug-fix release with few user-visible changes
3936
3937 ** It is now possible to use CCL-based coding systems for keyboard
3938 input.
3939
3940 ** ange-ftp now handles FTP security extensions, like Kerberos.
3941
3942 ** Rmail has been extended to recognize more forms of digest messages.
3943
3944 ** Now, most coding systems set in keyboard coding system work not
3945 only for character input, but also in incremental search. The
3946 exceptions are such coding systems that handle 2-byte character sets
3947 (e.g euc-kr, euc-jp) and that use ISO's escape sequence
3948 (e.g. iso-2022-jp). They are ignored in incremental search.
3949
3950 ** Support for Macintosh PowerPC-based machines running GNU/Linux has
3951 been added.
3952
3953 ^L
3954 * Emacs 20.6 is a bug-fix release with one user-visible change
3955
3956 ** Support for ARM-based non-RISCiX machines has been added.
3957
3958 ^L
3959 * Emacs 20.5 is a bug-fix release with no user-visible changes.
3960
3961 ** Not new, but not mentioned before:
3962 M-w when Transient Mark mode is enabled disables the mark.
3963 \f
3964 * Changes in Emacs 20.4
3965
3966 ** Init file may be called .emacs.el.
3967
3968 You can now call the Emacs init file `.emacs.el'.
3969 Formerly the name had to be `.emacs'. If you use the name
3970 `.emacs.el', you can byte-compile the file in the usual way.
3971
3972 If both `.emacs' and `.emacs.el' exist, the latter file
3973 is the one that is used.
3974
3975 ** shell-command, and shell-command-on-region, now return
3976 the exit code of the command (unless it is asynchronous).
3977 Also, you can specify a place to put the error output,
3978 separate from the command's regular output.
3979 Interactively, the variable shell-command-default-error-buffer
3980 says where to put error output; set it to a buffer name.
3981 In calls from Lisp, an optional argument ERROR-BUFFER specifies
3982 the buffer name.
3983
3984 When you specify a non-nil error buffer (or buffer name), any error
3985 output is inserted before point in that buffer, with \f\n to separate
3986 it from the previous batch of error output. The error buffer is not
3987 cleared, so error output from successive commands accumulates there.
3988
3989 ** Setting the default value of enable-multibyte-characters to nil in
3990 the .emacs file, either explicitly using setq-default, or via Custom,
3991 is now essentially equivalent to using --unibyte: all buffers
3992 created during startup will be made unibyte after loading .emacs.
3993
3994 ** C-x C-f now handles the wildcards * and ? in file names. For
3995 example, typing C-x C-f c*.c RET visits all the files whose names
3996 match c*.c. To visit a file whose name contains * or ?, add the
3997 quoting sequence /: to the beginning of the file name.
3998
3999 ** The M-x commands keep-lines, flush-lines and count-matches
4000 now have the same feature as occur and query-replace:
4001 if the pattern contains any upper case letters, then
4002 they never ignore case.
4003
4004 ** The end-of-line format conversion feature previously mentioned
4005 under `* Emacs 20.1 changes for MS-DOS and MS-Windows' actually
4006 applies to all operating systems. Emacs recognizes from the contents
4007 of a file what convention it uses to separate lines--newline, CRLF, or
4008 just CR--and automatically converts the contents to the normal Emacs
4009 convention (using newline to separate lines) for editing. This is a
4010 part of the general feature of coding system conversion.
4011
4012 If you subsequently save the buffer, Emacs converts the text back to
4013 the same format that was used in the file before.
4014
4015 You can turn off end-of-line conversion by setting the variable
4016 `inhibit-eol-conversion' to non-nil, e.g. with Custom in the MULE group.
4017
4018 ** The character set property `prefered-coding-system' has been
4019 renamed to `preferred-coding-system', for the sake of correct spelling.
4020 This is a fairly internal feature, so few programs should be affected.
4021
4022 ** Mode-line display of end-of-line format is changed.
4023 The indication of the end-of-line format of the file visited by a
4024 buffer is now more explicit when that format is not the usual one for
4025 your operating system. For example, the DOS-style end-of-line format
4026 is displayed as "(DOS)" on Unix and GNU/Linux systems. The usual
4027 end-of-line format is still displayed as a single character (colon for
4028 Unix, backslash for DOS and Windows, and forward slash for the Mac).
4029
4030 The values of the variables eol-mnemonic-unix, eol-mnemonic-dos,
4031 eol-mnemonic-mac, and eol-mnemonic-undecided, which are strings,
4032 control what is displayed in the mode line for each end-of-line
4033 format. You can now customize these variables.
4034
4035 ** In the previous version of Emacs, tar-mode didn't work well if a
4036 filename contained non-ASCII characters. Now this is fixed. Such a
4037 filename is decoded by file-name-coding-system if the default value of
4038 enable-multibyte-characters is non-nil.
4039
4040 ** The command temp-buffer-resize-mode toggles a minor mode
4041 in which temporary buffers (such as help buffers) are given
4042 windows just big enough to hold the whole contents.
4043
4044 ** If you use completion.el, you must now run the function
4045 dynamic-completion-mode to enable it. Just loading the file
4046 doesn't have any effect.
4047
4048 ** In Flyspell mode, the default is now to make just one Ispell process,
4049 not one per buffer.
4050
4051 ** If you use iswitchb but do not call (iswitchb-default-keybindings) to
4052 use the default keybindings, you will need to add the following line:
4053 (add-hook 'minibuffer-setup-hook 'iswitchb-minibuffer-setup)
4054
4055 ** Auto-show mode is no longer enabled just by loading auto-show.el.
4056 To control it, set `auto-show-mode' via Custom or use the
4057 `auto-show-mode' command.
4058
4059 ** Handling of X fonts' ascent/descent parameters has been changed to
4060 avoid redisplay problems. As a consequence, compared with previous
4061 versions the line spacing and frame size now differ with some font
4062 choices, typically increasing by a pixel per line. This change
4063 occurred in version 20.3 but was not documented then.
4064
4065 ** If you select the bar cursor style, it uses the frame's
4066 cursor-color, rather than the cursor foreground pixel.
4067
4068 ** In multibyte mode, Rmail decodes incoming MIME messages using the
4069 character set specified in the message. If you want to disable this
4070 feature, set the variable rmail-decode-mime-charset to nil.
4071
4072 ** Not new, but not mentioned previously in NEWS: when you use #! at
4073 the beginning of a file to make it executable and specify an
4074 interpreter program, Emacs looks on the second line for the -*- mode
4075 and variable specification, as well as on the first line.
4076
4077 ** Support for IBM codepage encoding of non-ASCII characters.
4078
4079 The new command M-x codepage-setup creates a special coding system
4080 that can be used to convert text between a specific IBM codepage and
4081 one of the character sets built into Emacs which matches that
4082 codepage. For example, codepage 850 corresponds to Latin-1 character
4083 set, codepage 855 corresponds to Cyrillic-ISO character set, etc.
4084
4085 Windows codepages 1250, 1251 and some others, where Windows deviates
4086 from the corresponding ISO character set, are also supported.
4087
4088 IBM box-drawing characters and other glyphs which don't have
4089 equivalents in the corresponding ISO character set, are converted to
4090 a character defined by dos-unsupported-char-glyph on MS-DOS, and to
4091 `?' on other systems.
4092
4093 IBM codepages are widely used on MS-DOS and MS-Windows, so this
4094 feature is most useful on those platforms, but it can also be used on
4095 Unix.
4096
4097 Emacs compiled for MS-DOS automatically loads the support for the
4098 current codepage when it starts.
4099
4100 ** Mail changes
4101
4102 *** When mail is sent using compose-mail (C-x m), and if
4103 `mail-send-nonascii' is set to the new default value `mime',
4104 appropriate MIME headers are added. The headers are added only if
4105 non-ASCII characters are present in the body of the mail, and no other
4106 MIME headers are already present. For example, the following three
4107 headers are added if the coding system used in the *mail* buffer is
4108 latin-1:
4109
4110 MIME-version: 1.0
4111 Content-type: text/plain; charset=iso-8859-1
4112 Content-Transfer-Encoding: 8bit
4113
4114 *** The new variable default-sendmail-coding-system specifies the
4115 default way to encode outgoing mail. This has higher priority than
4116 default-buffer-file-coding-system but has lower priority than
4117 sendmail-coding-system and the local value of
4118 buffer-file-coding-system.
4119
4120 You should not set this variable manually. Instead, set
4121 sendmail-coding-system to specify a fixed encoding for all outgoing
4122 mail.
4123
4124 *** When you try to send a message that contains non-ASCII characters,
4125 if the coding system specified by those variables doesn't handle them,
4126 Emacs will ask you to select a suitable coding system while showing a
4127 list of possible coding systems.
4128
4129 ** CC Mode changes
4130
4131 *** c-default-style can now take an association list that maps major
4132 modes to style names. When this variable is an alist, Java mode no
4133 longer hardcodes a setting to "java" style. See the variable's
4134 docstring for details.
4135
4136 *** It's now possible to put a list as the offset on a syntactic
4137 symbol. The list is evaluated recursively until a non-nil offset is
4138 found. This is useful to combine several lineup functions to act in a
4139 prioritized order on a single line. However, none of the supplied
4140 lineup functions use this feature currently.
4141
4142 *** New syntactic symbol catch-clause, which is used on the "catch" and
4143 "finally" lines in try-catch constructs in C++ and Java.
4144
4145 *** New cleanup brace-catch-brace on c-cleanup-list, which does for
4146 "catch" lines what brace-elseif-brace does for "else if" lines.
4147
4148 *** The braces of Java anonymous inner classes are treated separately
4149 from the braces of other classes in auto-newline mode. Two new
4150 symbols inexpr-class-open and inexpr-class-close may be used on
4151 c-hanging-braces-alist to control the automatic newlines used for
4152 anonymous classes.
4153
4154 *** Support for the Pike language added, along with new Pike specific
4155 syntactic symbols: inlambda, lambda-intro-cont
4156
4157 *** Support for Java anonymous classes via new syntactic symbol
4158 inexpr-class. New syntactic symbol inexpr-statement for Pike
4159 support and gcc-style statements inside expressions. New lineup
4160 function c-lineup-inexpr-block.
4161
4162 *** New syntactic symbol brace-entry-open which is used in brace lists
4163 (i.e. static initializers) when a list entry starts with an open
4164 brace. These used to be recognized as brace-list-entry's.
4165 c-electric-brace also recognizes brace-entry-open braces
4166 (brace-list-entry's can no longer be electrified).
4167
4168 *** New command c-indent-line-or-region, not bound by default.
4169
4170 *** `#' is only electric when typed in the indentation of a line.
4171
4172 *** Parentheses are now electric (via the new command c-electric-paren)
4173 for auto-reindenting lines when parens are typed.
4174
4175 *** In "gnu" style, inline-open offset is now set to zero.
4176
4177 *** Uniform handling of the inclass syntactic symbol. The indentation
4178 associated with it is now always relative to the class opening brace.
4179 This means that the indentation behavior has changed in some
4180 circumstances, but only if you've put anything besides 0 on the
4181 class-open syntactic symbol (none of the default styles do that).
4182
4183 ** Gnus changes.
4184
4185 *** New functionality for using Gnus as an offline newsreader has been
4186 added. A plethora of new commands and modes have been added. See the
4187 Gnus manual for the full story.
4188
4189 *** The nndraft backend has returned, but works differently than
4190 before. All Message buffers are now also articles in the nndraft
4191 group, which is created automatically.
4192
4193 *** `gnus-alter-header-function' can now be used to alter header
4194 values.
4195
4196 *** `gnus-summary-goto-article' now accept Message-ID's.
4197
4198 *** A new Message command for deleting text in the body of a message
4199 outside the region: `C-c C-v'.
4200
4201 *** You can now post to component group in nnvirtual groups with
4202 `C-u C-c C-c'.
4203
4204 *** `nntp-rlogin-program' -- new variable to ease customization.
4205
4206 *** `C-u C-c C-c' in `gnus-article-edit-mode' will now inhibit
4207 re-highlighting of the article buffer.
4208
4209 *** New element in `gnus-boring-article-headers' -- `long-to'.
4210
4211 *** `M-i' symbolic prefix command. See the section "Symbolic
4212 Prefixes" in the Gnus manual for details.
4213
4214 *** `L' and `I' in the summary buffer now take the symbolic prefix
4215 `a' to add the score rule to the "all.SCORE" file.
4216
4217 *** `gnus-simplify-subject-functions' variable to allow greater
4218 control over simplification.
4219
4220 *** `A T' -- new command for fetching the current thread.
4221
4222 *** `/ T' -- new command for including the current thread in the
4223 limit.
4224
4225 *** `M-RET' is a new Message command for breaking cited text.
4226
4227 *** \\1-expressions are now valid in `nnmail-split-methods'.
4228
4229 *** The `custom-face-lookup' function has been removed.
4230 If you used this function in your initialization files, you must
4231 rewrite them to use `face-spec-set' instead.
4232
4233 *** Cancelling now uses the current select method. Symbolic prefix
4234 `a' forces normal posting method.
4235
4236 *** New command to translate M******** sm*rtq**t*s into proper text
4237 -- `W d'.
4238
4239 *** For easier debugging of nntp, you can set `nntp-record-commands'
4240 to a non-nil value.
4241
4242 *** nntp now uses ~/.authinfo, a .netrc-like file, for controlling
4243 where and how to send AUTHINFO to NNTP servers.
4244
4245 *** A command for editing group parameters from the summary buffer
4246 has been added.
4247
4248 *** A history of where mails have been split is available.
4249
4250 *** A new article date command has been added -- `article-date-iso8601'.
4251
4252 *** Subjects can be simplified when threading by setting
4253 `gnus-score-thread-simplify'.
4254
4255 *** A new function for citing in Message has been added --
4256 `message-cite-original-without-signature'.
4257
4258 *** `article-strip-all-blank-lines' -- new article command.
4259
4260 *** A new Message command to kill to the end of the article has
4261 been added.
4262
4263 *** A minimum adaptive score can be specified by using the
4264 `gnus-adaptive-word-minimum' variable.
4265
4266 *** The "lapsed date" article header can be kept continually
4267 updated by the `gnus-start-date-timer' command.
4268
4269 *** Web listserv archives can be read with the nnlistserv backend.
4270
4271 *** Old dejanews archives can now be read by nnweb.
4272
4273 *** `gnus-posting-styles' has been re-activated.
4274
4275 ** Changes to TeX and LaTeX mode
4276
4277 *** The new variable `tex-start-options-string' can be used to give
4278 options for the TeX run. The default value causes TeX to run in
4279 nonstopmode. For an interactive TeX run set it to nil or "".
4280
4281 *** The command `tex-feed-input' sends input to the Tex Shell. In a
4282 TeX buffer it is bound to the keys C-RET, C-c RET, and C-c C-m (some
4283 of these keys may not work on all systems). For instance, if you run
4284 TeX interactively and if the TeX run stops because of an error, you
4285 can continue it without leaving the TeX buffer by typing C-RET.
4286
4287 *** The Tex Shell Buffer is now in `compilation-shell-minor-mode'.
4288 All error-parsing commands of the Compilation major mode are available
4289 but bound to keys that don't collide with the shell. Thus you can use
4290 the Tex Shell for command line executions like a usual shell.
4291
4292 *** The commands `tex-validate-region' and `tex-validate-buffer' check
4293 the matching of braces and $'s. The errors are listed in a *Occur*
4294 buffer and you can use C-c C-c or mouse-2 to go to a particular
4295 mismatch.
4296
4297 ** Changes to RefTeX mode
4298
4299 *** The table of contents buffer can now also display labels and
4300 file boundaries in addition to sections. Use `l', `i', and `c' keys.
4301
4302 *** Labels derived from context (the section heading) are now
4303 lowercase by default. To make the label legal in LaTeX, latin-1
4304 characters will lose their accent. All Mule characters will be
4305 removed from the label.
4306
4307 *** The automatic display of cross reference information can also use
4308 a window instead of the echo area. See variable `reftex-auto-view-crossref'.
4309
4310 *** kpsewhich can be used by RefTeX to find TeX and BibTeX files. See the
4311 customization group `reftex-finding-files'.
4312
4313 *** The option `reftex-bibfile-ignore-list' has been renamed to
4314 `reftex-bibfile-ignore-regexps' and indeed can be fed with regular
4315 expressions.
4316
4317 *** Multiple Selection buffers are now hidden buffers.
4318
4319 ** New/deleted modes and packages
4320
4321 *** The package snmp-mode.el provides major modes for editing SNMP and
4322 SNMPv2 MIBs. It has entries on `auto-mode-alist'.
4323
4324 *** The package sql.el provides a major mode, M-x sql-mode, for
4325 editing SQL files, and M-x sql-interactive-mode for interacting with
4326 SQL interpreters. It has an entry on `auto-mode-alist'.
4327
4328 *** M-x highlight-changes-mode provides a minor mode displaying buffer
4329 changes with a special face.
4330
4331 *** ispell4.el has been deleted. It got in the way of ispell.el and
4332 this was hard to fix reliably. It has long been obsolete -- use
4333 Ispell 3.1 and ispell.el.
4334 \f
4335 * MS-DOS changes in Emacs 20.4
4336
4337 ** Emacs compiled for MS-DOS now supports MULE features better.
4338 This includes support for display of all ISO 8859-N character sets,
4339 conversion to and from IBM codepage encoding of non-ASCII characters,
4340 and automatic setup of the MULE environment at startup. For details,
4341 check out the section `MS-DOS and MULE' in the manual.
4342
4343 The MS-DOS installation procedure automatically configures and builds
4344 Emacs with input method support if it finds an unpacked Leim
4345 distribution when the config.bat script is run.
4346
4347 ** Formerly, the value of lpr-command did not affect printing on
4348 MS-DOS unless print-region-function was set to nil, but now it
4349 controls whether an external program is invoked or output is written
4350 directly to a printer port. Similarly, in the previous version of
4351 Emacs, the value of ps-lpr-command did not affect PostScript printing
4352 on MS-DOS unless ps-printer-name was set to something other than a
4353 string (eg. t or `pipe'), but now it controls whether an external
4354 program is used. (These changes were made so that configuration of
4355 printing variables would be almost identical across all platforms.)
4356
4357 ** In the previous version of Emacs, PostScript and non-PostScript
4358 output was piped to external programs, but because most print programs
4359 available for MS-DOS and MS-Windows cannot read data from their standard
4360 input, on those systems the data to be output is now written to a
4361 temporary file whose name is passed as the last argument to the external
4362 program.
4363
4364 An exception is made for `print', a standard program on Windows NT,
4365 and `nprint', a standard program on Novell Netware. For both of these
4366 programs, the command line is constructed in the appropriate syntax
4367 automatically, using only the value of printer-name or ps-printer-name
4368 as appropriate--the value of the relevant `-switches' variable is
4369 ignored, as both programs have no useful switches.
4370
4371 ** The value of the variable dos-printer (cf. dos-ps-printer), if it has
4372 a value, overrides the value of printer-name (cf. ps-printer-name), on
4373 MS-DOS and MS-Windows only. This has been true since version 20.3, but
4374 was not documented clearly before.
4375
4376 ** All the Emacs games now work on MS-DOS terminals.
4377 This includes Tetris and Snake.
4378 \f
4379 * Lisp changes in Emacs 20.4
4380
4381 ** New functions line-beginning-position and line-end-position
4382 return the position of the beginning or end of the current line.
4383 They both accept an optional argument, which has the same
4384 meaning as the argument to beginning-of-line or end-of-line.
4385
4386 ** find-file and allied functions now have an optional argument
4387 WILDCARD. If this is non-nil, they do wildcard processing,
4388 and visit all files that match the wildcard pattern.
4389
4390 ** Changes in the file-attributes function.
4391
4392 *** The file size returned by file-attributes may be an integer or a float.
4393 It is an integer if the size fits in a Lisp integer, float otherwise.
4394
4395 *** The inode number returned by file-attributes may be an integer (if
4396 the number fits in a Lisp integer) or a cons cell containing two
4397 integers.
4398
4399 ** The new function directory-files-and-attributes returns a list of
4400 files in a directory and their attributes. It accepts the same
4401 arguments as directory-files and has similar semantics, except that
4402 file names and attributes are returned.
4403
4404 ** The new function file-attributes-lessp is a helper function for
4405 sorting the list generated by directory-files-and-attributes. It
4406 accepts two arguments, each a list of a file name and its atttributes.
4407 It compares the file names of each according to string-lessp and
4408 returns the result.
4409
4410 ** The new function file-expand-wildcards expands a wildcard-pattern
4411 to produce a list of existing files that match the pattern.
4412
4413 ** New functions for base64 conversion:
4414
4415 The function base64-encode-region converts a part of the buffer
4416 into the base64 code used in MIME. base64-decode-region
4417 performs the opposite conversion. Line-breaking is supported
4418 optionally.
4419
4420 Functions base64-encode-string and base64-decode-string do a similar
4421 job on the text in a string. They return the value as a new string.
4422
4423 **
4424 The new function process-running-child-p
4425 will tell you if a subprocess has given control of its
4426 terminal to its own child process.
4427
4428 ** interrupt-process and such functions have a new feature:
4429 when the second argument is `lambda', they send a signal
4430 to the running child of the subshell, if any, but if the shell
4431 itself owns its terminal, no signal is sent.
4432
4433 ** There are new widget types `plist' and `alist' which can
4434 be used for customizing variables whose values are plists or alists.
4435
4436 ** easymenu.el Now understands `:key-sequence' and `:style button'.
4437 :included is an alias for :visible.
4438
4439 easy-menu-add-item now understands the values returned by
4440 easy-menu-remove-item and easy-menu-item-present-p. This can be used
4441 to move or copy menu entries.
4442
4443 ** Multibyte editing changes
4444
4445 *** The definitions of sref and char-bytes are changed. Now, sref is
4446 an alias of aref and char-bytes always returns 1. This change is to
4447 make some Emacs Lisp code which works on 20.2 and earlier also
4448 work on the latest Emacs. Such code uses a combination of sref and
4449 char-bytes in a loop typically as below:
4450 (setq char (sref str idx)
4451 idx (+ idx (char-bytes idx)))
4452 The byte-compiler now warns that this is obsolete.
4453
4454 If you want to know how many bytes a specific multibyte character
4455 (say, CH) occupies in a multibyte buffer, use this code:
4456 (charset-bytes (char-charset ch))
4457
4458 *** In multibyte mode, when you narrow a buffer to some region, and the
4459 region is preceded or followed by non-ASCII codes, inserting or
4460 deleting at the head or the end of the region may signal this error:
4461
4462 Byte combining across boundary of accessible buffer text inhibitted
4463
4464 This is to avoid some bytes being combined together into a character
4465 across the boundary.
4466
4467 *** The functions find-charset-region and find-charset-string include
4468 `unknown' in the returned list in the following cases:
4469 o The current buffer or the target string is unibyte and
4470 contains 8-bit characters.
4471 o The current buffer or the target string is multibyte and
4472 contains invalid characters.
4473
4474 *** The functions decode-coding-region and encode-coding-region remove
4475 text properties of the target region. Ideally, they should correctly
4476 preserve text properties, but for the moment, it's hard. Removing
4477 text properties is better than preserving them in a less-than-correct
4478 way.
4479
4480 *** prefer-coding-system sets EOL conversion of default coding systems.
4481 If the argument to prefer-coding-system specifies a certain type of
4482 end of line conversion, the default coding systems set by
4483 prefer-coding-system will specify that conversion type for end of line.
4484
4485 *** The new function thai-compose-string can be used to properly
4486 compose Thai characters in a string.
4487
4488 ** The primitive `define-prefix-command' now takes an optional third
4489 argument NAME, which should be a string. It supplies the menu name
4490 for the created keymap. Keymaps created in order to be displayed as
4491 menus should always use the third argument.
4492
4493 ** The meanings of optional second arguments for read-char,
4494 read-event, and read-char-exclusive are flipped. Now the second
4495 arguments are INHERIT-INPUT-METHOD. These functions use the current
4496 input method (if any) if and only if INHERIT-INPUT-METHOD is non-nil.
4497
4498 ** The new function clear-this-command-keys empties out the contents
4499 of the vector that (this-command-keys) returns. This is useful in
4500 programs that read passwords, to prevent the passwords from echoing
4501 inadvertently as part of the next command in certain cases.
4502
4503 ** The new macro `with-temp-message' displays a temporary message in
4504 the echo area, while executing some Lisp code. Like `progn', it
4505 returns the value of the last form, but it also restores the previous
4506 echo area contents.
4507
4508 (with-temp-message MESSAGE &rest BODY)
4509
4510 ** The function `require' now takes an optional third argument
4511 NOERROR. If it is non-nil, then there is no error if the
4512 requested feature cannot be loaded.
4513
4514 ** In the function modify-face, an argument of (nil) for the
4515 foreground color, background color or stipple pattern
4516 means to clear out that attribute.
4517
4518 ** The `outer-window-id' frame property of an X frame
4519 gives the window number of the outermost X window for the frame.
4520
4521 ** Temporary buffers made with with-output-to-temp-buffer are now
4522 read-only by default, and normally use the major mode Help mode
4523 unless you put them in some other non-Fundamental mode before the
4524 end of with-output-to-temp-buffer.
4525
4526 ** The new functions gap-position and gap-size return information on
4527 the gap of the current buffer.
4528
4529 ** The new functions position-bytes and byte-to-position provide a way
4530 to convert between character positions and byte positions in the
4531 current buffer.
4532
4533 ** vc.el defines two new macros, `edit-vc-file' and `with-vc-file', to
4534 facilitate working with version-controlled files from Lisp programs.
4535 These macros check out a given file automatically if needed, and check
4536 it back in after any modifications have been made.
4537 \f
4538 * Installation Changes in Emacs 20.3
4539
4540 ** The default value of load-path now includes most subdirectories of
4541 the site-specific directories /usr/local/share/emacs/site-lisp and
4542 /usr/local/share/emacs/VERSION/site-lisp, in addition to those
4543 directories themselves. Both immediate subdirectories and
4544 subdirectories multiple levels down are added to load-path.
4545
4546 Not all subdirectories are included, though. Subdirectories whose
4547 names do not start with a letter or digit are excluded.
4548 Subdirectories named RCS or CVS are excluded. Also, a subdirectory
4549 which contains a file named `.nosearch' is excluded. You can use
4550 these methods to prevent certain subdirectories from being searched.
4551
4552 Emacs finds these subdirectories and adds them to load-path when it
4553 starts up. While it would be cleaner to find the subdirectories each
4554 time Emacs loads a file, that would be much slower.
4555
4556 This feature is an incompatible change. If you have stored some Emacs
4557 Lisp files in a subdirectory of the site-lisp directory specifically
4558 to prevent them from being used, you will need to rename the
4559 subdirectory to start with a non-alphanumeric character, or create a
4560 `.nosearch' file in it, in order to continue to achieve the desired
4561 results.
4562
4563 ** Emacs no longer includes an old version of the C preprocessor from
4564 GCC. This was formerly used to help compile Emacs with C compilers
4565 that had limits on the significant length of an identifier, but in
4566 fact we stopped supporting such compilers some time ago.
4567 \f
4568 * Changes in Emacs 20.3
4569
4570 ** The new command C-x z (repeat) repeats the previous command
4571 including its argument. If you repeat the z afterward,
4572 it repeats the command additional times; thus, you can
4573 perform many repetitions with one keystroke per repetition.
4574
4575 ** Emacs now supports "selective undo" which undoes only within a
4576 specified region. To do this, set point and mark around the desired
4577 region and type C-u C-x u (or C-u C-_). You can then continue undoing
4578 further, within the same region, by repeating the ordinary undo
4579 command C-x u or C-_. This will keep undoing changes that were made
4580 within the region you originally specified, until either all of them
4581 are undone, or it encounters a change which crosses the edge of that
4582 region.
4583
4584 In Transient Mark mode, undoing when a region is active requests
4585 selective undo.
4586
4587 ** If you specify --unibyte when starting Emacs, then all buffers are
4588 unibyte, except when a Lisp program specifically creates a multibyte
4589 buffer. Setting the environment variable EMACS_UNIBYTE has the same
4590 effect. The --no-unibyte option overrides EMACS_UNIBYTE and directs
4591 Emacs to run normally in multibyte mode.
4592
4593 The option --unibyte does not affect the reading of Emacs Lisp files,
4594 though. If you want a Lisp file to be read in unibyte mode, use
4595 -*-unibyte: t;-*- on its first line. That will force Emacs to
4596 load that file in unibyte mode, regardless of how Emacs was started.
4597
4598 ** toggle-enable-multibyte-characters no longer has a key binding and
4599 no longer appears in the menu bar. We've realized that changing the
4600 enable-multibyte-characters variable in an existing buffer is
4601 something that most users not do.
4602
4603 ** You can specify a coding system to use for the next cut or paste
4604 operations through the window system with the command C-x RET X.
4605 The coding system can make a difference for communication with other
4606 applications.
4607
4608 C-x RET x specifies a coding system for all subsequent cutting and
4609 pasting operations.
4610
4611 ** You can specify the printer to use for commands that do printing by
4612 setting the variable `printer-name'. Just what a printer name looks
4613 like depends on your operating system. You can specify a different
4614 printer for the Postscript printing commands by setting
4615 `ps-printer-name'.
4616
4617 ** Emacs now supports on-the-fly spell checking by the means of a
4618 minor mode. It is called M-x flyspell-mode. You don't have to remember
4619 any other special commands to use it, and you will hardly notice it
4620 except when you make a spelling error. Flyspell works by highlighting
4621 incorrect words as soon as they are completed or as soon as the cursor
4622 hits a new word.
4623
4624 Flyspell mode works with whichever dictionary you have selected for
4625 Ispell in Emacs. In TeX mode, it understands TeX syntax so as not
4626 to be confused by TeX commands.
4627
4628 You can correct a misspelled word by editing it into something
4629 correct. You can also correct it, or accept it as correct, by
4630 clicking on the word with Mouse-2; that gives you a pop-up menu
4631 of various alternative replacements and actions.
4632
4633 Flyspell mode also proposes "automatic" corrections. M-TAB replaces
4634 the current misspelled word with a possible correction. If several
4635 corrections are made possible, M-TAB cycles through them in
4636 alphabetical order, or in order of decreasing likelihood if
4637 flyspell-sort-corrections is nil.
4638
4639 Flyspell mode also flags an error when a word is repeated, if
4640 flyspell-mark-duplications-flag is non-nil.
4641
4642 ** Changes in input method usage.
4643
4644 Now you can use arrow keys (right, left, down, up) for selecting among
4645 the alternatives just the same way as you do by C-f, C-b, C-n, and C-p
4646 respectively.
4647
4648 You can use the ENTER key to accept the current conversion.
4649
4650 If you type TAB to display a list of alternatives, you can select one
4651 of the alternatives with Mouse-2.
4652
4653 The meaning of the variable `input-method-verbose-flag' is changed so
4654 that you can set it to t, nil, `default', or `complex-only'.
4655
4656 If the value is nil, extra guidance is never given.
4657
4658 If the value is t, extra guidance is always given.
4659
4660 If the value is `complex-only', extra guidance is always given only
4661 when you are using complex input methods such as chinese-py.
4662
4663 If the value is `default' (this is the default), extra guidance is
4664 given in the following case:
4665 o When you are using a complex input method.
4666 o When you are using a simple input method but not in the minibuffer.
4667
4668 If you are using Emacs through a very slow line, setting
4669 input-method-verbose-flag to nil or to complex-only is a good choice,
4670 and if you are using an input method you are not familiar with,
4671 setting it to t is helpful.
4672
4673 The old command select-input-method is now called set-input-method.
4674
4675 In the language environment "Korean", you can use the following
4676 keys:
4677 Shift-SPC toggle-korean-input-method
4678 C-F9 quail-hangul-switch-symbol-ksc
4679 F9 quail-hangul-switch-hanja
4680 These key bindings are canceled when you switch to another language
4681 environment.
4682
4683 ** The minibuffer history of file names now records the specified file
4684 names, not the entire minibuffer input. For example, if the
4685 minibuffer starts out with /usr/foo/, you might type in /etc/passwd to
4686 get
4687
4688 /usr/foo//etc/passwd
4689
4690 which stands for the file /etc/passwd.
4691
4692 Formerly, this used to put /usr/foo//etc/passwd in the history list.
4693 Now this puts just /etc/passwd in the history list.
4694
4695 ** If you are root, Emacs sets backup-by-copying-when-mismatch to t
4696 at startup, so that saving a file will be sure to preserve
4697 its owner and group.
4698
4699 ** find-func.el can now also find the place of definition of Emacs
4700 Lisp variables in user-loaded libraries.
4701
4702 ** C-x r t (string-rectangle) now deletes the existing rectangle
4703 contents before inserting the specified string on each line.
4704
4705 ** There is a new command delete-whitespace-rectangle
4706 which deletes whitespace starting from a particular column
4707 in all the lines on a rectangle. The column is specified
4708 by the left edge of the rectangle.
4709
4710 ** You can now store a number into a register with C-u NUMBER C-x r n REG,
4711 increment it by INC with C-u INC C-x r + REG (to increment by one, omit
4712 C-u INC), and insert it in the buffer with C-x r g REG. This is useful
4713 for writing keyboard macros.
4714
4715 ** The new command M-x speedbar displays a frame in which directories,
4716 files, and tags can be displayed, manipulated, and jumped to. The
4717 frame defaults to 20 characters in width, and is the same height as
4718 the frame that it was started from. Some major modes define
4719 additional commands for the speedbar, including Rmail, GUD/GDB, and
4720 info.
4721
4722 ** query-replace-regexp is now bound to C-M-%.
4723
4724 ** In Transient Mark mode, when the region is active, M-x
4725 query-replace and the other replace commands now operate on the region
4726 contents only.
4727
4728 ** M-x write-region, when used interactively, now asks for
4729 confirmation before overwriting an existing file. When you call
4730 the function from a Lisp program, a new optional argument CONFIRM
4731 says whether to ask for confirmation in this case.
4732
4733 ** If you use find-file-literally and the file is already visited
4734 non-literally, the command asks you whether to revisit the file
4735 literally. If you say no, it signals an error.
4736
4737 ** Major modes defined with the "derived mode" feature
4738 now use the proper name for the mode hook: WHATEVER-mode-hook.
4739 Formerly they used the name WHATEVER-mode-hooks, but that is
4740 inconsistent with Emacs conventions.
4741
4742 ** shell-command-on-region (and shell-command) reports success or
4743 failure if the command produces no output.
4744
4745 ** Set focus-follows-mouse to nil if your window system or window
4746 manager does not transfer focus to another window when you just move
4747 the mouse.
4748
4749 ** mouse-menu-buffer-maxlen has been renamed to
4750 mouse-buffer-menu-maxlen to be consistent with the other related
4751 function and variable names.
4752
4753 ** The new variable auto-coding-alist specifies coding systems for
4754 reading specific files. This has higher priority than
4755 file-coding-system-alist.
4756
4757 ** If you set the variable unibyte-display-via-language-environment to
4758 t, then Emacs displays non-ASCII characters are displayed by
4759 converting them to the equivalent multibyte characters according to
4760 the current language environment. As a result, they are displayed
4761 according to the current fontset.
4762
4763 ** C-q's handling of codes in the range 0200 through 0377 is changed.
4764
4765 The codes in the range 0200 through 0237 are inserted as one byte of
4766 that code regardless of the values of nonascii-translation-table and
4767 nonascii-insert-offset.
4768
4769 For the codes in the range 0240 through 0377, if
4770 enable-multibyte-characters is non-nil and nonascii-translation-table
4771 nor nonascii-insert-offset can't convert them to valid multibyte
4772 characters, they are converted to Latin-1 characters.
4773
4774 ** If you try to find a file that is not read-accessible, you now get
4775 an error, rather than an empty buffer and a warning.
4776
4777 ** In the minibuffer history commands M-r and M-s, an upper case
4778 letter in the regular expression forces case-sensitive search.
4779
4780 ** In the *Help* buffer, cross-references to commands and variables
4781 are inferred and hyperlinked. Use C-h m in Help mode for the relevant
4782 command keys.
4783
4784 ** M-x apropos-command, with a prefix argument, no longer looks for
4785 user option variables--instead it looks for noninteractive functions.
4786
4787 Meanwhile, the command apropos-variable normally searches for
4788 user option variables; with a prefix argument, it looks at
4789 all variables that have documentation.
4790
4791 ** When you type a long line in the minibuffer, and the minibuffer
4792 shows just one line, automatically scrolling works in a special way
4793 that shows you overlap with the previous line of text. The variable
4794 minibuffer-scroll-overlap controls how many characters of overlap
4795 it should show; the default is 20.
4796
4797 Meanwhile, Resize Minibuffer mode is still available; in that mode,
4798 the minibuffer grows taller (up to a point) as needed to show the whole
4799 of your input.
4800
4801 ** The new command M-x customize-changed-options lets you customize
4802 all the options whose meanings or default values have changed in
4803 recent Emacs versions. You specify a previous Emacs version number as
4804 argument, and the command creates a customization buffer showing all
4805 the customizable options which were changed since that version.
4806 Newly added options are included as well.
4807
4808 If you don't specify a particular version number argument,
4809 then the customization buffer shows all the customizable options
4810 for which Emacs versions of changes are recorded.
4811
4812 This function is also bound to the Changed Options entry in the
4813 Customize menu.
4814
4815 ** When you run M-x grep with a prefix argument, it figures out
4816 the tag around point and puts that into the default grep command.
4817
4818 ** The new command M-* (pop-tag-mark) pops back through a history of
4819 buffer positions from which M-. or other tag-finding commands were
4820 invoked.
4821
4822 ** The new variable comment-padding specifies the number of spaces
4823 that `comment-region' will insert before the actual text of the comment.
4824 The default is 1.
4825
4826 ** In Fortran mode the characters `.', `_' and `$' now have symbol
4827 syntax, not word syntax. Fortran mode now supports `imenu' and has
4828 new commands fortran-join-line (M-^) and fortran-narrow-to-subprogram
4829 (C-x n d). M-q can be used to fill a statement or comment block
4830 sensibly.
4831
4832 ** GUD now supports jdb, the Java debugger, and pdb, the Python debugger.
4833
4834 ** If you set the variable add-log-keep-changes-together to a non-nil
4835 value, the command `C-x 4 a' will automatically notice when you make
4836 two entries in one day for one file, and combine them.
4837
4838 ** You can use the command M-x diary-mail-entries to mail yourself a
4839 reminder about upcoming diary entries. See the documentation string
4840 for a sample shell script for calling this function automatically
4841 every night.
4842
4843 ** Desktop changes
4844
4845 *** All you need to do to enable use of the Desktop package, is to set
4846 the variable desktop-enable to t with Custom.
4847
4848 *** Minor modes are now restored. Which minor modes are restored
4849 and how modes are restored is controlled by `desktop-minor-mode-table'.
4850
4851 ** There is no need to do anything special, now, to enable Gnus to
4852 read and post multi-lingual articles.
4853
4854 ** Outline mode has now support for showing hidden outlines when
4855 doing an isearch. In order for this to happen search-invisible should
4856 be set to open (the default). If an isearch match is inside a hidden
4857 outline the outline is made visible. If you continue pressing C-s and
4858 the match moves outside the formerly invisible outline, the outline is
4859 made invisible again.
4860
4861 ** Mail reading and sending changes
4862
4863 *** The Rmail e command now switches to displaying the whole header of
4864 the message before it lets you edit the message. This is so that any
4865 changes you make in the header will not be lost if you subsequently
4866 toggle.
4867
4868 *** The w command in Rmail, which writes the message body into a file,
4869 now works in the summary buffer as well. (The command to delete the
4870 summary buffer is now Q.) The default file name for the w command, if
4871 the message has no subject, is stored in the variable
4872 rmail-default-body-file.
4873
4874 *** Most of the commands and modes that operate on mail and netnews no
4875 longer depend on the value of mail-header-separator. Instead, they
4876 handle whatever separator the buffer happens to use.
4877
4878 *** If you set mail-signature to a value which is not t, nil, or a string,
4879 it should be an expression. When you send a message, this expression
4880 is evaluated to insert the signature.
4881
4882 *** The new Lisp library feedmail.el (version 8) enhances processing of
4883 outbound email messages. It works in coordination with other email
4884 handling packages (e.g., rmail, VM, gnus) and is responsible for
4885 putting final touches on messages and actually submitting them for
4886 transmission. Users of the emacs program "fakemail" might be
4887 especially interested in trying feedmail.
4888
4889 feedmail is not enabled by default. See comments at the top of
4890 feedmail.el for set-up instructions. Among the bigger features
4891 provided by feedmail are:
4892
4893 **** you can park outgoing messages into a disk-based queue and
4894 stimulate sending some or all of them later (handy for laptop users);
4895 there is also a queue for draft messages
4896
4897 **** you can get one last look at the prepped outbound message and
4898 be prompted for confirmation
4899
4900 **** does smart filling of address headers
4901
4902 **** can generate a MESSAGE-ID: line and a DATE: line; the date can be
4903 the time the message was written or the time it is being sent; this
4904 can make FCC copies more closely resemble copies that recipients get
4905
4906 **** you can specify an arbitrary function for actually transmitting
4907 the message; included in feedmail are interfaces for /bin/[r]mail,
4908 /usr/lib/sendmail, and elisp smtpmail; it's easy to write a new
4909 function for something else (10-20 lines of elisp)
4910
4911 ** Dired changes
4912
4913 *** The Dired function dired-do-toggle, which toggles marked and unmarked
4914 files, is now bound to "t" instead of "T".
4915
4916 *** dired-at-point has been added to ffap.el. It allows one to easily
4917 run Dired on the directory name at point.
4918
4919 *** Dired has a new command: %g. It searches the contents of
4920 files in the directory and marks each file that contains a match
4921 for a specified regexp.
4922
4923 ** VC Changes
4924
4925 *** New option vc-ignore-vc-files lets you turn off version control
4926 conveniently.
4927
4928 *** VC Dired has been completely rewritten. It is now much
4929 faster, especially for CVS, and works very similar to ordinary
4930 Dired.
4931
4932 VC Dired is invoked by typing C-x v d and entering the name of the
4933 directory to display. By default, VC Dired gives you a recursive
4934 listing of all files at or below the given directory which are
4935 currently locked (for CVS, all files not up-to-date are shown).
4936
4937 You can change the listing format by setting vc-dired-recurse to nil,
4938 then it shows only the given directory, and you may also set
4939 vc-dired-terse-display to nil, then it shows all files under version
4940 control plus the names of any subdirectories, so that you can type `i'
4941 on such lines to insert them manually, as in ordinary Dired.
4942
4943 All Dired commands operate normally in VC Dired, except for `v', which
4944 is redefined as the version control prefix. That means you may type
4945 `v l', `v =' etc. to invoke `vc-print-log', `vc-diff' and the like on
4946 the file named in the current Dired buffer line. `v v' invokes
4947 `vc-next-action' on this file, or on all files currently marked.
4948
4949 The new command `v t' (vc-dired-toggle-terse-mode) allows you to
4950 toggle between terse display (only locked files) and full display (all
4951 VC files plus subdirectories). There is also a special command,
4952 `* l', to mark all files currently locked.
4953
4954 Giving a prefix argument to C-x v d now does the same thing as in
4955 ordinary Dired: it allows you to supply additional options for the ls
4956 command in the minibuffer, to fine-tune VC Dired's output.
4957
4958 *** Under CVS, if you merge changes from the repository into a working
4959 file, and CVS detects conflicts, VC now offers to start an ediff
4960 session to resolve them.
4961
4962 Alternatively, you can use the new command `vc-resolve-conflicts' to
4963 resolve conflicts in a file at any time. It works in any buffer that
4964 contains conflict markers as generated by rcsmerge (which is what CVS
4965 uses as well).
4966
4967 *** You can now transfer changes between branches, using the new
4968 command vc-merge (C-x v m). It is implemented for RCS and CVS. When
4969 you invoke it in a buffer under version-control, you can specify
4970 either an entire branch or a pair of versions, and the changes on that
4971 branch or between the two versions are merged into the working file.
4972 If this results in any conflicts, they may be resolved interactively,
4973 using ediff.
4974
4975 ** Changes in Font Lock
4976
4977 *** The face and variable previously known as font-lock-reference-face
4978 are now called font-lock-constant-face to better reflect their typical
4979 use for highlighting constants and labels. (Its face properties are
4980 unchanged.) The variable font-lock-reference-face remains for now for
4981 compatibility reasons, but its value is font-lock-constant-face.
4982
4983 ** Frame name display changes
4984
4985 *** The command set-frame-name lets you set the name of the current
4986 frame. You can use the new command select-frame-by-name to select and
4987 raise a frame; this is mostly useful on character-only terminals, or
4988 when many frames are invisible or iconified.
4989
4990 *** On character-only terminal (not a window system), changing the
4991 frame name is now reflected on the mode line and in the Buffers/Frames
4992 menu.
4993
4994 ** Comint (subshell) changes
4995
4996 *** In Comint modes, the commands to kill, stop or interrupt a
4997 subjob now also kill pending input. This is for compatibility
4998 with ordinary shells, where the signal characters do this.
4999
5000 *** There are new commands in Comint mode.
5001
5002 C-c C-x fetches the "next" line from the input history;
5003 that is, the line after the last line you got.
5004 You can use this command to fetch successive lines, one by one.
5005
5006 C-c SPC accumulates lines of input. More precisely, it arranges to
5007 send the current line together with the following line, when you send
5008 the following line.
5009
5010 C-c C-a if repeated twice consecutively now moves to the process mark,
5011 which separates the pending input from the subprocess output and the
5012 previously sent input.
5013
5014 C-c M-r now runs comint-previous-matching-input-from-input;
5015 it searches for a previous command, using the current pending input
5016 as the search string.
5017
5018 *** New option compilation-scroll-output can be set to scroll
5019 automatically in compilation-mode windows.
5020
5021 ** C mode changes
5022
5023 *** Multiline macros are now handled, both as they affect indentation,
5024 and as recognized syntax. New syntactic symbol cpp-macro-cont is
5025 assigned to second and subsequent lines of a multiline macro
5026 definition.
5027
5028 *** A new style "user" which captures all non-hook-ified
5029 (i.e. top-level) .emacs file variable settings and customizations.
5030 Style "cc-mode" is an alias for "user" and is deprecated. "gnu"
5031 style is still the default however.
5032
5033 *** "java" style now conforms to Sun's JDK coding style.
5034
5035 *** There are new commands c-beginning-of-defun, c-end-of-defun which
5036 are alternatives which you could bind to C-M-a and C-M-e if you prefer
5037 them. They do not have key bindings by default.
5038
5039 *** New and improved implementations of M-a (c-beginning-of-statement)
5040 and M-e (c-end-of-statement).
5041
5042 *** C++ namespace blocks are supported, with new syntactic symbols
5043 namespace-open, namespace-close, and innamespace.
5044
5045 *** File local variable settings of c-file-style and c-file-offsets
5046 makes the style variables local to that buffer only.
5047
5048 *** New indentation functions c-lineup-close-paren,
5049 c-indent-one-line-block, c-lineup-dont-change.
5050
5051 *** Improvements (hopefully!) to the way CC Mode is loaded. You
5052 should now be able to do a (require 'cc-mode) to get the entire
5053 package loaded properly for customization in your .emacs file. A new
5054 variable c-initialize-on-load controls this and is t by default.
5055
5056 ** Changes to hippie-expand.
5057
5058 *** New customization variable `hippie-expand-dabbrev-skip-space'. If
5059 non-nil, trailing spaces may be included in the abbreviation to search for,
5060 which then gives the same behavior as the original `dabbrev-expand'.
5061
5062 *** New customization variable `hippie-expand-dabbrev-as-symbol'. If
5063 non-nil, characters of syntax '_' is considered part of the word when
5064 expanding dynamically.
5065
5066 *** New customization variable `hippie-expand-no-restriction'. If
5067 non-nil, narrowed buffers are widened before they are searched.
5068
5069 *** New customization variable `hippie-expand-only-buffers'. If
5070 non-empty, buffers searched are restricted to the types specified in
5071 this list. Useful for example when constructing new special-purpose
5072 expansion functions with `make-hippie-expand-function'.
5073
5074 *** Text properties of the expansion are no longer copied.
5075
5076 ** Changes in BibTeX mode.
5077
5078 *** Any titleword matching a regexp in the new variable
5079 bibtex-autokey-titleword-ignore (case sensitive) is ignored during
5080 automatic key generation. This replaces variable
5081 bibtex-autokey-titleword-first-ignore, which only checked for matches
5082 against the first word in the title.
5083
5084 *** Autokey generation now uses all words from the title, not just
5085 capitalized words. To avoid conflicts with existing customizations,
5086 bibtex-autokey-titleword-ignore is set up such that words starting with
5087 lowerkey characters will still be ignored. Thus, if you want to use
5088 lowercase words from the title, you will have to overwrite the
5089 bibtex-autokey-titleword-ignore standard setting.
5090
5091 *** Case conversion of names and title words for automatic key
5092 generation is more flexible. Variable bibtex-autokey-preserve-case is
5093 replaced by bibtex-autokey-titleword-case-convert and
5094 bibtex-autokey-name-case-convert.
5095
5096 ** Changes in vcursor.el.
5097
5098 *** Support for character terminals is available: there is a new keymap
5099 and the vcursor will appear as an arrow between buffer text. A
5100 variable `vcursor-interpret-input' allows input from the vcursor to be
5101 entered exactly as if typed. Numerous functions, including
5102 `vcursor-compare-windows', have been rewritten to improve consistency
5103 in the selection of windows and corresponding keymaps.
5104
5105 *** vcursor options can now be altered with M-x customize under the
5106 Editing group once the package is loaded.
5107
5108 *** Loading vcursor now does not define keys by default, as this is
5109 generally a bad side effect. Use M-x customize to set
5110 vcursor-key-bindings to t to restore the old behaviour.
5111
5112 *** vcursor-auto-disable can be `copy', which turns off copying from the
5113 vcursor, but doesn't disable it, after any non-vcursor command.
5114
5115 ** Ispell changes.
5116
5117 *** You can now spell check comments and strings in the current
5118 buffer with M-x ispell-comments-and-strings. Comments and strings
5119 are identified by syntax tables in effect.
5120
5121 *** Generic region skipping implemented.
5122 A single buffer can be broken into a number of regions where text will
5123 and will not be checked. The definitions of the regions can be user
5124 defined. New applications and improvements made available by this
5125 include:
5126
5127 o URLs are automatically skipped
5128 o EMail message checking is vastly improved.
5129
5130 *** Ispell can highlight the erroneous word even on non-window terminals.
5131
5132 ** Changes to RefTeX mode
5133
5134 RefTeX has been updated in order to make it more usable with very
5135 large projects (like a several volume math book). The parser has been
5136 re-written from scratch. To get maximum speed from RefTeX, check the
5137 section `Optimizations' in the manual.
5138
5139 *** New recursive parser.
5140
5141 The old version of RefTeX created a single large buffer containing the
5142 entire multifile document in order to parse the document. The new
5143 recursive parser scans the individual files.
5144
5145 *** Parsing only part of a document.
5146
5147 Reparsing of changed document parts can now be made faster by enabling
5148 partial scans. To use this feature, read the documentation string of
5149 the variable `reftex-enable-partial-scans' and set the variable to t.
5150
5151 (setq reftex-enable-partial-scans t)
5152
5153 *** Storing parsing information in a file.
5154
5155 This can improve startup times considerably. To turn it on, use
5156
5157 (setq reftex-save-parse-info t)
5158
5159 *** Using multiple selection buffers
5160
5161 If the creation of label selection buffers is too slow (this happens
5162 for large documents), you can reuse these buffers by setting
5163
5164 (setq reftex-use-multiple-selection-buffers t)
5165
5166 *** References to external documents.
5167
5168 The LaTeX package `xr' allows to cross-reference labels in external
5169 documents. RefTeX can provide information about the external
5170 documents as well. To use this feature, set up the \externaldocument
5171 macros required by the `xr' package and rescan the document with
5172 RefTeX. The external labels can then be accessed with the `x' key in
5173 the selection buffer provided by `reftex-reference' (bound to `C-c )').
5174 The `x' key also works in the table of contents buffer.
5175
5176 *** Many more labeled LaTeX environments are recognized by default.
5177
5178 The builtin command list now covers all the standard LaTeX commands,
5179 and all of the major packages included in the LaTeX distribution.
5180
5181 Also, RefTeX now understands the \appendix macro and changes
5182 the enumeration of sections in the *toc* buffer accordingly.
5183
5184 *** Mouse support for selection and *toc* buffers
5185
5186 The mouse can now be used to select items in the selection and *toc*
5187 buffers. See also the new option `reftex-highlight-selection'.
5188
5189 *** New keymaps for selection and table of contents modes.
5190
5191 The selection processes for labels and citation keys, and the table of
5192 contents buffer now have their own keymaps: `reftex-select-label-map',
5193 `reftex-select-bib-map', `reftex-toc-map'. The selection processes
5194 have a number of new keys predefined. In particular, TAB lets you
5195 enter a label with completion. Check the on-the-fly help (press `?'
5196 at the selection prompt) or read the Info documentation to find out
5197 more.
5198
5199 *** Support for the varioref package
5200
5201 The `v' key in the label selection buffer toggles \ref versus \vref.
5202
5203 *** New hooks
5204
5205 Three new hooks can be used to redefine the way labels, references,
5206 and citations are created. These hooks are
5207 `reftex-format-label-function', `reftex-format-ref-function',
5208 `reftex-format-cite-function'.
5209
5210 *** Citations outside LaTeX
5211
5212 The command `reftex-citation' may also be used outside LaTeX (e.g. in
5213 a mail buffer). See the Info documentation for details.
5214
5215 *** Short context is no longer fontified.
5216
5217 The short context in the label menu no longer copies the
5218 fontification from the text in the buffer. If you prefer it to be
5219 fontified, use
5220
5221 (setq reftex-refontify-context t)
5222
5223 ** file-cache-minibuffer-complete now accepts a prefix argument.
5224 With a prefix argument, it does not try to do completion of
5225 the file name within its directory; it only checks for other
5226 directories that contain the same file name.
5227
5228 Thus, given the file name Makefile, and assuming that a file
5229 Makefile.in exists in the same directory, ordinary
5230 file-cache-minibuffer-complete will try to complete Makefile to
5231 Makefile.in and will therefore never look for other directories that
5232 have Makefile. A prefix argument tells it not to look for longer
5233 names such as Makefile.in, so that instead it will look for other
5234 directories--just as if the name were already complete in its present
5235 directory.
5236
5237 ** New modes and packages
5238
5239 *** There is a new alternative major mode for Perl, Cperl mode.
5240 It has many more features than Perl mode, and some people prefer
5241 it, but some do not.
5242
5243 *** There is a new major mode, M-x vhdl-mode, for editing files of VHDL
5244 code.
5245
5246 *** M-x which-function-mode enables a minor mode that displays the
5247 current function name continuously in the mode line, as you move
5248 around in a buffer.
5249
5250 Which Function mode is effective in major modes which support Imenu.
5251
5252 *** Gametree is a major mode for editing game analysis trees. The author
5253 uses it for keeping notes about his postal Chess games, but it should
5254 be helpful for other two-player games as well, as long as they have an
5255 established system of notation similar to Chess.
5256
5257 *** The new minor mode checkdoc-minor-mode provides Emacs Lisp
5258 documentation string checking for style and spelling. The style
5259 guidelines are found in the Emacs Lisp programming manual.
5260
5261 *** The net-utils package makes some common networking features
5262 available in Emacs. Some of these functions are wrappers around
5263 system utilities (ping, nslookup, etc); others are implementations of
5264 simple protocols (finger, whois) in Emacs Lisp. There are also
5265 functions to make simple connections to TCP/IP ports for debugging and
5266 the like.
5267
5268 *** highlight-changes-mode is a minor mode that uses colors to
5269 identify recently changed parts of the buffer text.
5270
5271 *** The new package `midnight' lets you specify things to be done
5272 within Emacs at midnight--by default, kill buffers that you have not
5273 used in a considerable time. To use this feature, customize
5274 the user option `midnight-mode' to t.
5275
5276 *** The file generic-x.el defines a number of simple major modes.
5277
5278 apache-generic-mode: For Apache and NCSA httpd configuration files
5279 samba-generic-mode: Samba configuration files
5280 fvwm-generic-mode: For fvwm initialization files
5281 x-resource-generic-mode: For X resource files
5282 hosts-generic-mode: For hosts files (.rhosts, /etc/hosts, etc)
5283 mailagent-rules-generic-mode: For mailagent .rules files
5284 javascript-generic-mode: For JavaScript files
5285 vrml-generic-mode: For VRML files
5286 java-manifest-generic-mode: For Java MANIFEST files
5287 java-properties-generic-mode: For Java property files
5288 mailrc-generic-mode: For .mailrc files
5289
5290 Platform-specific modes:
5291
5292 prototype-generic-mode: For Solaris/Sys V prototype files
5293 pkginfo-generic-mode: For Solaris/Sys V pkginfo files
5294 alias-generic-mode: For C shell alias files
5295 inf-generic-mode: For MS-Windows INF files
5296 ini-generic-mode: For MS-Windows INI files
5297 reg-generic-mode: For MS-Windows Registry files
5298 bat-generic-mode: For MS-Windows BAT scripts
5299 rc-generic-mode: For MS-Windows Resource files
5300 rul-generic-mode: For InstallShield scripts
5301 \f
5302 * Lisp changes in Emacs 20.3 since the Emacs Lisp Manual was published
5303
5304 ** If you want a Lisp file to be read in unibyte mode,
5305 use -*-unibyte: t;-*- on its first line.
5306 That will force Emacs to read that file in unibyte mode.
5307 Otherwise, the file will be loaded and byte-compiled in multibyte mode.
5308
5309 Thus, each lisp file is read in a consistent way regardless of whether
5310 you started Emacs with --unibyte, so that a Lisp program gives
5311 consistent results regardless of how Emacs was started.
5312
5313 ** The new function assoc-default is useful for searching an alist,
5314 and using a default value if the key is not found there. You can
5315 specify a comparison predicate, so this function is useful for
5316 searching comparing a string against an alist of regular expressions.
5317
5318 ** The functions unibyte-char-to-multibyte and
5319 multibyte-char-to-unibyte convert between unibyte and multibyte
5320 character codes, in a way that is appropriate for the current language
5321 environment.
5322
5323 ** The functions read-event, read-char and read-char-exclusive now
5324 take two optional arguments. PROMPT, if non-nil, specifies a prompt
5325 string. SUPPRESS-INPUT-METHOD, if non-nil, says to disable the
5326 current input method for reading this one event.
5327
5328 ** Two new variables print-escape-nonascii and print-escape-multibyte
5329 now control whether to output certain characters as
5330 backslash-sequences. print-escape-nonascii applies to single-byte
5331 non-ASCII characters; print-escape-multibyte applies to multibyte
5332 characters. Both of these variables are used only when printing
5333 in readable fashion (prin1 uses them, princ does not).
5334 \f
5335 * Lisp changes in Emacs 20.3 before the Emacs Lisp Manual was published
5336
5337 ** Compiled Emacs Lisp files made with the modified "MBSK" version
5338 of Emacs 20.2 do not work in Emacs 20.3.
5339
5340 ** Buffer positions are now measured in characters, as they were
5341 in Emacs 19 and before. This means that (forward-char 1)
5342 always increases point by 1.
5343
5344 The function chars-in-region now just subtracts its arguments. It is
5345 considered obsolete. The function char-boundary-p has been deleted.
5346
5347 See below for additional changes relating to multibyte characters.
5348
5349 ** defcustom, defface and defgroup now accept the keyword `:version'.
5350 Use this to specify in which version of Emacs a certain variable's
5351 default value changed. For example,
5352
5353 (defcustom foo-max 34 "*Maximum number of foo's allowed."
5354 :type 'integer
5355 :group 'foo
5356 :version "20.3")
5357
5358 (defgroup foo-group nil "The foo group."
5359 :version "20.3")
5360
5361 If an entire new group is added or the variables in it have the
5362 default values changed, then just add a `:version' to that group. It
5363 is recommended that new packages added to the distribution contain a
5364 `:version' in the top level group.
5365
5366 This information is used to control the customize-changed-options command.
5367
5368 ** It is now an error to change the value of a symbol whose name
5369 starts with a colon--if it is interned in the standard obarray.
5370
5371 However, setting such a symbol to its proper value, which is that
5372 symbol itself, is not an error. This is for the sake of programs that
5373 support previous Emacs versions by explicitly setting these variables
5374 to themselves.
5375
5376 If you set the variable keyword-symbols-constant-flag to nil,
5377 this error is suppressed, and you can set these symbols to any
5378 values whatever.
5379
5380 ** There is a new debugger command, R.
5381 It evaluates an expression like e, but saves the result
5382 in the buffer *Debugger-record*.
5383
5384 ** Frame-local variables.
5385
5386 You can now make a variable local to various frames. To do this, call
5387 the function make-variable-frame-local; this enables frames to have
5388 local bindings for that variable.
5389
5390 These frame-local bindings are actually frame parameters: you create a
5391 frame-local binding in a specific frame by calling
5392 modify-frame-parameters and specifying the variable name as the
5393 parameter name.
5394
5395 Buffer-local bindings take precedence over frame-local bindings.
5396 Thus, if the current buffer has a buffer-local binding, that binding is
5397 active; otherwise, if the selected frame has a frame-local binding,
5398 that binding is active; otherwise, the default binding is active.
5399
5400 It would not be hard to implement window-local bindings, but it is not
5401 clear that this would be very useful; windows tend to come and go in a
5402 very transitory fashion, so that trying to produce any specific effect
5403 through a window-local binding would not be very robust.
5404
5405 ** `sregexq' and `sregex' are two new functions for constructing
5406 "symbolic regular expressions." These are Lisp expressions that, when
5407 evaluated, yield conventional string-based regexps. The symbolic form
5408 makes it easier to construct, read, and maintain complex patterns.
5409 See the documentation in sregex.el.
5410
5411 ** parse-partial-sexp's return value has an additional element which
5412 is used to pass information along if you pass it to another call to
5413 parse-partial-sexp, starting its scan where the first call ended.
5414 The contents of this field are not yet finalized.
5415
5416 ** eval-region now accepts a fourth optional argument READ-FUNCTION.
5417 If it is non-nil, that function is used instead of `read'.
5418
5419 ** unload-feature by default removes the feature's functions from
5420 known hooks to avoid trouble, but a package providing FEATURE can
5421 define a hook FEATURE-unload-hook to be run by unload-feature instead.
5422
5423 ** read-from-minibuffer no longer returns the argument DEFAULT-VALUE
5424 when the user enters empty input. It now returns the null string, as
5425 it did in Emacs 19. The default value is made available in the
5426 history via M-n, but it is not applied here as a default.
5427
5428 The other, more specialized minibuffer-reading functions continue to
5429 return the default value (not the null string) when the user enters
5430 empty input.
5431
5432 ** The new variable read-buffer-function controls which routine to use
5433 for selecting buffers. For example, if you set this variable to
5434 `iswitchb-read-buffer', iswitchb will be used to read buffer names.
5435 Other functions can also be used if they accept the same arguments as
5436 `read-buffer' and return the selected buffer name as a string.
5437
5438 ** The new function read-passwd reads a password from the terminal,
5439 echoing a period for each character typed. It takes three arguments:
5440 a prompt string, a flag which says "read it twice to make sure", and a
5441 default password to use if the user enters nothing.
5442
5443 ** The variable fill-nobreak-predicate gives major modes a way to
5444 specify not to break a line at certain places. Its value is a
5445 function which is called with no arguments, with point located at the
5446 place where a break is being considered. If the function returns
5447 non-nil, then the line won't be broken there.
5448
5449 ** window-end now takes an optional second argument, UPDATE.
5450 If this is non-nil, then the function always returns an accurate
5451 up-to-date value for the buffer position corresponding to the
5452 end of the window, even if this requires computation.
5453
5454 ** other-buffer now takes an optional argument FRAME
5455 which specifies which frame's buffer list to use.
5456 If it is nil, that means use the selected frame's buffer list.
5457
5458 ** The new variable buffer-display-time, always local in every buffer,
5459 holds the value of (current-time) as of the last time that a window
5460 was directed to display this buffer.
5461
5462 ** It is now meaningful to compare two window-configuration objects
5463 with `equal'. Two window-configuration objects are equal if they
5464 describe equivalent arrangements of windows, in the same frame--in
5465 other words, if they would give the same results if passed to
5466 set-window-configuration.
5467
5468 ** compare-window-configurations is a new function that compares two
5469 window configurations loosely. It ignores differences in saved buffer
5470 positions and scrolling, and considers only the structure and sizes of
5471 windows and the choice of buffers to display.
5472
5473 ** The variable minor-mode-overriding-map-alist allows major modes to
5474 override the key bindings of a minor mode. The elements of this alist
5475 look like the elements of minor-mode-map-alist: (VARIABLE . KEYMAP).
5476
5477 If the VARIABLE in an element of minor-mode-overriding-map-alist has a
5478 non-nil value, the paired KEYMAP is active, and totally overrides the
5479 map (if any) specified for the same variable in minor-mode-map-alist.
5480
5481 minor-mode-overriding-map-alist is automatically local in all buffers,
5482 and it is meant to be set by major modes.
5483
5484 ** The function match-string-no-properties is like match-string
5485 except that it discards all text properties from the result.
5486
5487 ** The function load-average now accepts an optional argument
5488 USE-FLOATS. If it is non-nil, the load average values are returned as
5489 floating point numbers, rather than as integers to be divided by 100.
5490
5491 ** The new variable temporary-file-directory specifies the directory
5492 to use for creating temporary files. The default value is determined
5493 in a reasonable way for your operating system; on GNU and Unix systems
5494 it is based on the TMP and TMPDIR environment variables.
5495
5496 ** Menu changes
5497
5498 *** easymenu.el now uses the new menu item format and supports the
5499 keywords :visible and :filter. The existing keyword :keys is now
5500 better supported.
5501
5502 The variable `easy-menu-precalculate-equivalent-keybindings' controls
5503 a new feature which calculates keyboard equivalents for the menu when
5504 you define the menu. The default is t. If you rarely use menus, you
5505 can set the variable to nil to disable this precalculation feature;
5506 then the calculation is done only if you use the menu bar.
5507
5508 *** A new format for menu items is supported.
5509
5510 In a keymap, a key binding that has the format
5511 (STRING . REAL-BINDING) or (STRING HELP-STRING . REAL-BINDING)
5512 defines a menu item. Now a menu item definition may also be a list that
5513 starts with the symbol `menu-item'.
5514
5515 The format is:
5516 (menu-item ITEM-NAME) or
5517 (menu-item ITEM-NAME REAL-BINDING . ITEM-PROPERTY-LIST)
5518 where ITEM-NAME is an expression which evaluates to the menu item
5519 string, and ITEM-PROPERTY-LIST has the form of a property list.
5520 The supported properties include
5521
5522 :enable FORM Evaluate FORM to determine whether the
5523 item is enabled.
5524 :visible FORM Evaluate FORM to determine whether the
5525 item should appear in the menu.
5526 :filter FILTER-FN
5527 FILTER-FN is a function of one argument,
5528 which will be REAL-BINDING.
5529 It should return a binding to use instead.
5530 :keys DESCRIPTION
5531 DESCRIPTION is a string that describes an equivalent keyboard
5532 binding for for REAL-BINDING. DESCRIPTION is expanded with
5533 `substitute-command-keys' before it is used.
5534 :key-sequence KEY-SEQUENCE
5535 KEY-SEQUENCE is a key-sequence for an equivalent
5536 keyboard binding.
5537 :key-sequence nil
5538 This means that the command normally has no
5539 keyboard equivalent.
5540 :help HELP HELP is the extra help string (not currently used).
5541 :button (TYPE . SELECTED)
5542 TYPE is :toggle or :radio.
5543 SELECTED is a form, to be evaluated, and its
5544 value says whether this button is currently selected.
5545
5546 Buttons are at the moment only simulated by prefixes in the menu.
5547 Eventually ordinary X-buttons may be supported.
5548
5549 (menu-item ITEM-NAME) defines unselectable item.
5550
5551 ** New event types
5552
5553 *** The new event type `mouse-wheel' is generated by a wheel on a
5554 mouse (such as the MS Intellimouse). The event contains a delta that
5555 corresponds to the amount and direction that the wheel is rotated,
5556 which is typically used to implement a scroll or zoom. The format is:
5557
5558 (mouse-wheel POSITION DELTA)
5559
5560 where POSITION is a list describing the position of the event in the
5561 same format as a mouse-click event, and DELTA is a signed number
5562 indicating the number of increments by which the wheel was rotated. A
5563 negative DELTA indicates that the wheel was rotated backwards, towards
5564 the user, and a positive DELTA indicates that the wheel was rotated
5565 forward, away from the user.
5566
5567 As of now, this event type is generated only on MS Windows.
5568
5569 *** The new event type `drag-n-drop' is generated when a group of
5570 files is selected in an application outside of Emacs, and then dragged
5571 and dropped onto an Emacs frame. The event contains a list of
5572 filenames that were dragged and dropped, which are then typically
5573 loaded into Emacs. The format is:
5574
5575 (drag-n-drop POSITION FILES)
5576
5577 where POSITION is a list describing the position of the event in the
5578 same format as a mouse-click event, and FILES is the list of filenames
5579 that were dragged and dropped.
5580
5581 As of now, this event type is generated only on MS Windows.
5582
5583 ** Changes relating to multibyte characters.
5584
5585 *** The variable enable-multibyte-characters is now read-only;
5586 any attempt to set it directly signals an error. The only way
5587 to change this value in an existing buffer is with set-buffer-multibyte.
5588
5589 *** In a string constant, `\ ' now stands for "nothing at all". You
5590 can use it to terminate a hex escape which is followed by a character
5591 that could otherwise be read as part of the hex escape.
5592
5593 *** String indices are now measured in characters, as they were
5594 in Emacs 19 and before.
5595
5596 The function chars-in-string has been deleted.
5597 The function concat-chars has been renamed to `string'.
5598
5599 *** The function set-buffer-multibyte sets the flag in the current
5600 buffer that says whether the buffer uses multibyte representation or
5601 unibyte representation. If the argument is nil, it selects unibyte
5602 representation. Otherwise it selects multibyte representation.
5603
5604 This function does not change the contents of the buffer, viewed
5605 as a sequence of bytes. However, it does change the contents
5606 viewed as characters; a sequence of two bytes which is treated as
5607 one character when the buffer uses multibyte representation
5608 will count as two characters using unibyte representation.
5609
5610 This function sets enable-multibyte-characters to record which
5611 representation is in use. It also adjusts various data in the buffer
5612 (including its markers, overlays and text properties) so that they are
5613 consistent with the new representation.
5614
5615 *** string-make-multibyte takes a string and converts it to multibyte
5616 representation. Most of the time, you don't need to care
5617 about the representation, because Emacs converts when necessary;
5618 however, it makes a difference when you compare strings.
5619
5620 The conversion of non-ASCII characters works by adding the value of
5621 nonascii-insert-offset to each character, or by translating them
5622 using the table nonascii-translation-table.
5623
5624 *** string-make-unibyte takes a string and converts it to unibyte
5625 representation. Most of the time, you don't need to care about the
5626 representation, but it makes a difference when you compare strings.
5627
5628 The conversion from multibyte to unibyte representation
5629 loses information; the only time Emacs performs it automatically
5630 is when inserting a multibyte string into a unibyte buffer.
5631
5632 *** string-as-multibyte takes a string, and returns another string
5633 which contains the same bytes, but treats them as multibyte.
5634
5635 *** string-as-unibyte takes a string, and returns another string
5636 which contains the same bytes, but treats them as unibyte.
5637
5638 *** The new function compare-strings lets you compare
5639 portions of two strings. Unibyte strings are converted to multibyte,
5640 so that a unibyte string can match a multibyte string.
5641 You can specify whether to ignore case or not.
5642
5643 *** assoc-ignore-case now uses compare-strings so that
5644 it can treat unibyte and multibyte strings as equal.
5645
5646 *** Regular expression operations and buffer string searches now
5647 convert the search pattern to multibyte or unibyte to accord with the
5648 buffer or string being searched.
5649
5650 One consequence is that you cannot always use \200-\377 inside of
5651 [...] to match all non-ASCII characters. This does still work when
5652 searching or matching a unibyte buffer or string, but not when
5653 searching or matching a multibyte string. Unfortunately, there is no
5654 obvious choice of syntax to use within [...] for that job. But, what
5655 you want is just to match all non-ASCII characters, the regular
5656 expression [^\0-\177] works for it.
5657
5658 *** Structure of coding system changed.
5659
5660 All coding systems (including aliases and subsidiaries) are named
5661 by symbols; the symbol's `coding-system' property is a vector
5662 which defines the coding system. Aliases share the same vector
5663 as the principal name, so that altering the contents of this
5664 vector affects the principal name and its aliases. You can define
5665 your own alias name of a coding system by the function
5666 define-coding-system-alias.
5667
5668 The coding system definition includes a property list of its own. Use
5669 the new functions `coding-system-get' and `coding-system-put' to
5670 access such coding system properties as post-read-conversion,
5671 pre-write-conversion, character-translation-table-for-decode,
5672 character-translation-table-for-encode, mime-charset, and
5673 safe-charsets. For instance, (coding-system-get 'iso-latin-1
5674 'mime-charset) gives the corresponding MIME-charset parameter
5675 `iso-8859-1'.
5676
5677 Among the coding system properties listed above, safe-charsets is new.
5678 The value of this property is a list of character sets which this
5679 coding system can correctly encode and decode. For instance:
5680 (coding-system-get 'iso-latin-1 'safe-charsets) => (ascii latin-iso8859-1)
5681
5682 Here, "correctly encode" means that the encoded character sets can
5683 also be handled safely by systems other than Emacs as far as they
5684 are capable of that coding system. Though, Emacs itself can encode
5685 the other character sets and read it back correctly.
5686
5687 *** The new function select-safe-coding-system can be used to find a
5688 proper coding system for encoding the specified region or string.
5689 This function requires a user interaction.
5690
5691 *** The new functions find-coding-systems-region and
5692 find-coding-systems-string are helper functions used by
5693 select-safe-coding-system. They return a list of all proper coding
5694 systems to encode a text in some region or string. If you don't want
5695 a user interaction, use one of these functions instead of
5696 select-safe-coding-system.
5697
5698 *** The explicit encoding and decoding functions, such as
5699 decode-coding-region and encode-coding-string, now set
5700 last-coding-system-used to reflect the actual way encoding or decoding
5701 was done.
5702
5703 *** The new function detect-coding-with-language-environment can be
5704 used to detect a coding system of text according to priorities of
5705 coding systems used by some specific language environment.
5706
5707 *** The functions detect-coding-region and detect-coding-string always
5708 return a list if the arg HIGHEST is nil. Thus, if only ASCII
5709 characters are found, they now return a list of single element
5710 `undecided' or its subsidiaries.
5711
5712 *** The new functions coding-system-change-eol-conversion and
5713 coding-system-change-text-conversion can be used to get a different
5714 coding system than what specified only in how end-of-line or text is
5715 converted.
5716
5717 *** The new function set-selection-coding-system can be used to set a
5718 coding system for communicating with other X clients.
5719
5720 *** The function `map-char-table' now passes as argument only valid
5721 character codes, plus generic characters that stand for entire
5722 character sets or entire subrows of a character set. In other words,
5723 each time `map-char-table' calls its FUNCTION argument, the key value
5724 either will be a valid individual character code, or will stand for a
5725 range of characters.
5726
5727 *** The new function `char-valid-p' can be used for checking whether a
5728 Lisp object is a valid character code or not.
5729
5730 *** The new function `charset-after' returns a charset of a character
5731 in the current buffer at position POS.
5732
5733 *** Input methods are now implemented using the variable
5734 input-method-function. If this is non-nil, its value should be a
5735 function; then, whenever Emacs reads an input event that is a printing
5736 character with no modifier bits, it calls that function, passing the
5737 event as an argument. Often this function will read more input, first
5738 binding input-method-function to nil.
5739
5740 The return value should be a list of the events resulting from input
5741 method processing. These events will be processed sequentially as
5742 input, before resorting to unread-command-events. Events returned by
5743 the input method function are not passed to the input method function,
5744 not even if they are printing characters with no modifier bits.
5745
5746 The input method function is not called when reading the second and
5747 subsequent events of a key sequence.
5748
5749 *** You can customize any language environment by using
5750 set-language-environment-hook and exit-language-environment-hook.
5751
5752 The hook `exit-language-environment-hook' should be used to undo
5753 customizations that you made with set-language-environment-hook. For
5754 instance, if you set up a special key binding for a specific language
5755 environment by set-language-environment-hook, you should set up
5756 exit-language-environment-hook to restore the normal key binding.
5757 \f
5758 * Changes in Emacs 20.1
5759
5760 ** Emacs has a new facility for customization of its many user
5761 options. It is called M-x customize. With this facility you can look
5762 at the many user options in an organized way; they are grouped into a
5763 tree structure.
5764
5765 M-x customize also knows what sorts of values are legitimate for each
5766 user option and ensures that you don't use invalid values.
5767
5768 With M-x customize, you can set options either for the present Emacs
5769 session or permanently. (Permanent settings are stored automatically
5770 in your .emacs file.)
5771
5772 ** Scroll bars are now on the left side of the window.
5773 You can change this with M-x customize-option scroll-bar-mode.
5774
5775 ** The mode line no longer includes the string `Emacs'.
5776 This makes more space in the mode line for other information.
5777
5778 ** When you select a region with the mouse, it is highlighted
5779 immediately afterward. At that time, if you type the DELETE key, it
5780 kills the region.
5781
5782 The BACKSPACE key, and the ASCII character DEL, do not do this; they
5783 delete the character before point, as usual.
5784
5785 ** In an incremental search the whole current match is highlighted
5786 on terminals which support this. (You can disable this feature
5787 by setting search-highlight to nil.)
5788
5789 ** In the minibuffer, in some cases, you can now use M-n to
5790 insert the default value into the minibuffer as text. In effect,
5791 the default value (if the minibuffer routines know it) is tacked
5792 onto the history "in the future". (The more normal use of the
5793 history list is to use M-p to insert minibuffer input used in the
5794 past.)
5795
5796 ** In Text mode, now only blank lines separate paragraphs.
5797 This makes it possible to get the full benefit of Adaptive Fill mode
5798 in Text mode, and other modes derived from it (such as Mail mode).
5799 TAB in Text mode now runs the command indent-relative; this
5800 makes a practical difference only when you use indented paragraphs.
5801
5802 As a result, the old Indented Text mode is now identical to Text mode,
5803 and is an alias for it.
5804
5805 If you want spaces at the beginning of a line to start a paragraph,
5806 use the new mode, Paragraph Indent Text mode.
5807
5808 ** Scrolling changes
5809
5810 *** Scroll commands to scroll a whole screen now preserve the screen
5811 position of the cursor, if scroll-preserve-screen-position is non-nil.
5812
5813 In this mode, if you scroll several screens back and forth, finishing
5814 on the same screen where you started, the cursor goes back to the line
5815 where it started.
5816
5817 *** If you set scroll-conservatively to a small number, then when you
5818 move point a short distance off the screen, Emacs will scroll the
5819 screen just far enough to bring point back on screen, provided that
5820 does not exceed `scroll-conservatively' lines.
5821
5822 *** The new variable scroll-margin says how close point can come to the
5823 top or bottom of a window. It is a number of screen lines; if point
5824 comes within that many lines of the top or bottom of the window, Emacs
5825 recenters the window.
5826
5827 ** International character set support (MULE)
5828
5829 Emacs now supports a wide variety of international character sets,
5830 including European variants of the Latin alphabet, as well as Chinese,
5831 Devanagari (Hindi and Marathi), Ethiopian, Greek, IPA, Japanese,
5832 Korean, Lao, Russian, Thai, Tibetan, and Vietnamese scripts. These
5833 features have been merged from the modified version of Emacs known as
5834 MULE (for "MULti-lingual Enhancement to GNU Emacs")
5835
5836 Users of these scripts have established many more-or-less standard
5837 coding systems for storing files. Emacs uses a single multibyte
5838 character encoding within Emacs buffers; it can translate from a wide
5839 variety of coding systems when reading a file and can translate back
5840 into any of these coding systems when saving a file.
5841
5842 Keyboards, even in the countries where these character sets are used,
5843 generally don't have keys for all the characters in them. So Emacs
5844 supports various "input methods", typically one for each script or
5845 language, to make it possible to type them.
5846
5847 The Emacs internal multibyte encoding represents a non-ASCII
5848 character as a sequence of bytes in the range 0200 through 0377.
5849
5850 The new prefix key C-x RET is used for commands that pertain
5851 to multibyte characters, coding systems, and input methods.
5852
5853 You can disable multibyte character support as follows:
5854
5855 (setq-default enable-multibyte-characters nil)
5856
5857 Calling the function standard-display-european turns off multibyte
5858 characters, unless you specify a non-nil value for the second
5859 argument, AUTO. This provides compatibility for people who are
5860 already using standard-display-european to continue using unibyte
5861 characters for their work until they want to change.
5862
5863 *** Input methods
5864
5865 An input method is a kind of character conversion which is designed
5866 specifically for interactive input. In Emacs, typically each language
5867 has its own input method (though sometimes several languages which use
5868 the same characters can share one input method). Some languages
5869 support several input methods.
5870
5871 The simplest kind of input method works by mapping ASCII letters into
5872 another alphabet. This is how the Greek and Russian input methods
5873 work.
5874
5875 A more powerful technique is composition: converting sequences of
5876 characters into one letter. Many European input methods use
5877 composition to produce a single non-ASCII letter from a sequence which
5878 consists of a letter followed by diacritics. For example, a' is one
5879 sequence of two characters that might be converted into a single
5880 letter.
5881
5882 The input methods for syllabic scripts typically use mapping followed
5883 by conversion. The input methods for Thai and Korean work this way.
5884 First, letters are mapped into symbols for particular sounds or tone
5885 marks; then, sequences of these which make up a whole syllable are
5886 mapped into one syllable sign--most often a "composite character".
5887
5888 None of these methods works very well for Chinese and Japanese, so
5889 they are handled specially. First you input a whole word using
5890 phonetic spelling; then, after the word is in the buffer, Emacs
5891 converts it into one or more characters using a large dictionary.
5892
5893 Since there is more than one way to represent a phonetically spelled
5894 word using Chinese characters, Emacs can only guess which one to use;
5895 typically these input methods give you a way to say "guess again" if
5896 the first guess is wrong.
5897
5898 *** The command C-x RET m (toggle-enable-multibyte-characters)
5899 turns multibyte character support on or off for the current buffer.
5900
5901 If multibyte character support is turned off in a buffer, then each
5902 byte is a single character, even codes 0200 through 0377--exactly as
5903 they did in Emacs 19.34. This includes the features for support for
5904 the European characters, ISO Latin-1 and ISO Latin-2.
5905
5906 However, there is no need to turn off multibyte character support to
5907 use ISO Latin-1 or ISO Latin-2; the Emacs multibyte character set
5908 includes all the characters in these character sets, and Emacs can
5909 translate automatically to and from either one.
5910
5911 *** Visiting a file in unibyte mode.
5912
5913 Turning off multibyte character support in the buffer after visiting a
5914 file with multibyte code conversion will display the multibyte
5915 sequences already in the buffer, byte by byte. This is probably not
5916 what you want.
5917
5918 If you want to edit a file of unibyte characters (Latin-1, for
5919 example), you can do it by specifying `no-conversion' as the coding
5920 system when reading the file. This coding system also turns off
5921 multibyte characters in that buffer.
5922
5923 If you turn off multibyte character support entirely, this turns off
5924 character conversion as well.
5925
5926 *** Displaying international characters on X Windows.
5927
5928 A font for X typically displays just one alphabet or script.
5929 Therefore, displaying the entire range of characters Emacs supports
5930 requires using many fonts.
5931
5932 Therefore, Emacs now supports "fontsets". Each fontset is a
5933 collection of fonts, each assigned to a range of character codes.
5934
5935 A fontset has a name, like a font. Individual fonts are defined by
5936 the X server; fontsets are defined within Emacs itself. But once you
5937 have defined a fontset, you can use it in a face or a frame just as
5938 you would use a font.
5939
5940 If a fontset specifies no font for a certain character, or if it
5941 specifies a font that does not exist on your system, then it cannot
5942 display that character. It will display an empty box instead.
5943
5944 The fontset height and width are determined by the ASCII characters
5945 (that is, by the font in the fontset which is used for ASCII
5946 characters). If another font in the fontset has a different height,
5947 or the wrong width, then characters assigned to that font are clipped,
5948 and displayed within a box if highlight-wrong-size-font is non-nil.
5949
5950 *** Defining fontsets.
5951
5952 Emacs does not use any fontset by default. Its default font is still
5953 chosen as in previous versions. You can tell Emacs to use a fontset
5954 with the `-fn' option or the `Font' X resource.
5955
5956 Emacs creates a standard fontset automatically according to the value
5957 of standard-fontset-spec. This fontset's short name is
5958 `fontset-standard'. Bold, italic, and bold-italic variants of the
5959 standard fontset are created automatically.
5960
5961 If you specify a default ASCII font with the `Font' resource or `-fn'
5962 argument, a fontset is generated from it. This works by replacing the
5963 FOUNDARY, FAMILY, ADD_STYLE, and AVERAGE_WIDTH fields of the font name
5964 with `*' then using this to specify a fontset. This fontset's short
5965 name is `fontset-startup'.
5966
5967 Emacs checks resources of the form Fontset-N where N is 0, 1, 2...
5968 The resource value should have this form:
5969 FONTSET-NAME, [CHARSET-NAME:FONT-NAME]...
5970 FONTSET-NAME should have the form of a standard X font name, except:
5971 * most fields should be just the wild card "*".
5972 * the CHARSET_REGISTRY field should be "fontset"
5973 * the CHARSET_ENCODING field can be any nickname of the fontset.
5974 The construct CHARSET-NAME:FONT-NAME can be repeated any number
5975 of times; each time specifies the font for one character set.
5976 CHARSET-NAME should be the name name of a character set, and
5977 FONT-NAME should specify an actual font to use for that character set.
5978
5979 Each of these fontsets has an alias which is made from the
5980 last two font name fields, CHARSET_REGISTRY and CHARSET_ENCODING.
5981 You can refer to the fontset by that alias or by its full name.
5982
5983 For any character sets that you don't mention, Emacs tries to choose a
5984 font by substituting into FONTSET-NAME. For instance, with the
5985 following resource,
5986 Emacs*Fontset-0: -*-fixed-medium-r-normal-*-24-*-*-*-*-*-fontset-24
5987 the font for ASCII is generated as below:
5988 -*-fixed-medium-r-normal-*-24-*-ISO8859-1
5989 Here is the substitution rule:
5990 Change CHARSET_REGISTRY and CHARSET_ENCODING to that of the charset
5991 defined in the variable x-charset-registries. For instance, ASCII has
5992 the entry (ascii . "ISO8859-1") in this variable. Then, reduce
5993 sequences of wild cards -*-...-*- with a single wildcard -*-.
5994 (This is to prevent use of auto-scaled fonts.)
5995
5996 The function which processes the fontset resource value to create the
5997 fontset is called create-fontset-from-fontset-spec. You can also call
5998 that function explicitly to create a fontset.
5999
6000 With the X resource Emacs.Font, you can specify a fontset name just
6001 like an actual font name. But be careful not to specify a fontset
6002 name in a wildcard resource like Emacs*Font--that tries to specify the
6003 fontset for other purposes including menus, and they cannot handle
6004 fontsets.
6005
6006 *** The command M-x set-language-environment sets certain global Emacs
6007 defaults for a particular choice of language.
6008
6009 Selecting a language environment typically specifies a default input
6010 method and which coding systems to recognize automatically when
6011 visiting files. However, it does not try to reread files you have
6012 already visited; the text in those buffers is not affected. The
6013 language environment may also specify a default choice of coding
6014 system for new files that you create.
6015
6016 It makes no difference which buffer is current when you use
6017 set-language-environment, because these defaults apply globally to the
6018 whole Emacs session.
6019
6020 For example, M-x set-language-environment RET Latin-1 RET
6021 chooses the Latin-1 character set. In the .emacs file, you can do this
6022 with (set-language-environment "Latin-1").
6023
6024 *** The command C-x RET f (set-buffer-file-coding-system)
6025 specifies the file coding system for the current buffer. This
6026 specifies what sort of character code translation to do when saving
6027 the file. As an argument, you must specify the name of one of the
6028 coding systems that Emacs supports.
6029
6030 *** The command C-x RET c (universal-coding-system-argument)
6031 lets you specify a coding system when you read or write a file.
6032 This command uses the minibuffer to read a coding system name.
6033 After you exit the minibuffer, the specified coding system
6034 is used for *the immediately following command*.
6035
6036 So if the immediately following command is a command to read or
6037 write a file, it uses the specified coding system for that file.
6038
6039 If the immediately following command does not use the coding system,
6040 then C-x RET c ultimately has no effect.
6041
6042 For example, C-x RET c iso-8859-1 RET C-x C-f temp RET
6043 visits the file `temp' treating it as ISO Latin-1.
6044
6045 *** You can specify the coding system for a file using the -*-
6046 construct. Include `coding: CODINGSYSTEM;' inside the -*-...-*-
6047 to specify use of coding system CODINGSYSTEM. You can also
6048 specify the coding system in a local variable list at the end
6049 of the file.
6050
6051 *** The command C-x RET t (set-terminal-coding-system) specifies
6052 the coding system for terminal output. If you specify a character
6053 code for terminal output, all characters output to the terminal are
6054 translated into that character code.
6055
6056 This feature is useful for certain character-only terminals built in
6057 various countries to support the languages of those countries.
6058
6059 By default, output to the terminal is not translated at all.
6060
6061 *** The command C-x RET k (set-keyboard-coding-system) specifies
6062 the coding system for keyboard input.
6063
6064 Character code translation of keyboard input is useful for terminals
6065 with keys that send non-ASCII graphic characters--for example,
6066 some terminals designed for ISO Latin-1 or subsets of it.
6067
6068 By default, keyboard input is not translated at all.
6069
6070 Character code translation of keyboard input is similar to using an
6071 input method, in that both define sequences of keyboard input that
6072 translate into single characters. However, input methods are designed
6073 to be convenient for interactive use, while the code translations are
6074 designed to work with terminals.
6075
6076 *** The command C-x RET p (set-buffer-process-coding-system)
6077 specifies the coding system for input and output to a subprocess.
6078 This command applies to the current buffer; normally, each subprocess
6079 has its own buffer, and thus you can use this command to specify
6080 translation to and from a particular subprocess by giving the command
6081 in the corresponding buffer.
6082
6083 By default, process input and output are not translated at all.
6084
6085 *** The variable file-name-coding-system specifies the coding system
6086 to use for encoding file names before operating on them.
6087 It is also used for decoding file names obtained from the system.
6088
6089 *** The command C-\ (toggle-input-method) activates or deactivates
6090 an input method. If no input method has been selected before, the
6091 command prompts for you to specify the language and input method you
6092 want to use.
6093
6094 C-u C-\ (select-input-method) lets you switch to a different input
6095 method. C-h C-\ (or C-h I) describes the current input method.
6096
6097 *** Some input methods remap the keyboard to emulate various keyboard
6098 layouts commonly used for particular scripts. How to do this
6099 remapping properly depends on your actual keyboard layout. To specify
6100 which layout your keyboard has, use M-x quail-set-keyboard-layout.
6101
6102 *** The command C-h C (describe-coding-system) displays
6103 the coding systems currently selected for various purposes, plus
6104 related information.
6105
6106 *** The command C-h h (view-hello-file) displays a file called
6107 HELLO, which has examples of text in many languages, using various
6108 scripts.
6109
6110 *** The command C-h L (describe-language-support) displays
6111 information about the support for a particular language.
6112 You specify the language as an argument.
6113
6114 *** The mode line now contains a letter or character that identifies
6115 the coding system used in the visited file. It normally follows the
6116 first dash.
6117
6118 A dash indicates the default state of affairs: no code conversion
6119 (except CRLF => newline if appropriate). `=' means no conversion
6120 whatsoever. The ISO 8859 coding systems are represented by digits
6121 1 through 9. Other coding systems are represented by letters:
6122
6123 A alternativnyj (Russian)
6124 B big5 (Chinese)
6125 C cn-gb-2312 (Chinese)
6126 C iso-2022-cn (Chinese)
6127 D in-is13194-devanagari (Indian languages)
6128 E euc-japan (Japanese)
6129 I iso-2022-cjk or iso-2022-ss2 (Chinese, Japanese, Korean)
6130 J junet (iso-2022-7) or old-jis (iso-2022-jp-1978-irv) (Japanese)
6131 K euc-korea (Korean)
6132 R koi8 (Russian)
6133 Q tibetan
6134 S shift_jis (Japanese)
6135 T lao
6136 T tis620 (Thai)
6137 V viscii or vscii (Vietnamese)
6138 i iso-2022-lock (Chinese, Japanese, Korean)
6139 k iso-2022-kr (Korean)
6140 v viqr (Vietnamese)
6141 z hz (Chinese)
6142
6143 When you are using a character-only terminal (not a window system),
6144 two additional characters appear in between the dash and the file
6145 coding system. These two characters describe the coding system for
6146 keyboard input, and the coding system for terminal output.
6147
6148 *** The new variable rmail-file-coding-system specifies the code
6149 conversion to use for RMAIL files. The default value is nil.
6150
6151 When you read mail with Rmail, each message is decoded automatically
6152 into Emacs' internal format. This has nothing to do with
6153 rmail-file-coding-system. That variable controls reading and writing
6154 Rmail files themselves.
6155
6156 *** The new variable sendmail-coding-system specifies the code
6157 conversion for outgoing mail. The default value is nil.
6158
6159 Actually, there are three different ways of specifying the coding system
6160 for sending mail:
6161
6162 - If you use C-x RET f in the mail buffer, that takes priority.
6163 - Otherwise, if you set sendmail-coding-system non-nil, that specifies it.
6164 - Otherwise, the default coding system for new files is used,
6165 if that is non-nil. That comes from your language environment.
6166 - Otherwise, Latin-1 is used.
6167
6168 *** The command C-h t (help-with-tutorial) accepts a prefix argument
6169 to specify the language for the tutorial file. Currently, English,
6170 Japanese, Korean and Thai are supported. We welcome additional
6171 translations.
6172
6173 ** An easy new way to visit a file with no code or format conversion
6174 of any kind: Use M-x find-file-literally. There is also a command
6175 insert-file-literally which inserts a file into the current buffer
6176 without any conversion.
6177
6178 ** C-q's handling of octal character codes is changed.
6179 You can now specify any number of octal digits.
6180 RET terminates the digits and is discarded;
6181 any other non-digit terminates the digits and is then used as input.
6182
6183 ** There are new commands for looking up Info documentation for
6184 functions, variables and file names used in your programs.
6185
6186 Type M-x info-lookup-symbol to look up a symbol in the buffer at point.
6187 Type M-x info-lookup-file to look up a file in the buffer at point.
6188
6189 Precisely which Info files are used to look it up depends on the major
6190 mode. For example, in C mode, the GNU libc manual is used.
6191
6192 ** M-TAB in most programming language modes now runs the command
6193 complete-symbol. This command performs completion on the symbol name
6194 in the buffer before point.
6195
6196 With a numeric argument, it performs completion based on the set of
6197 symbols documented in the Info files for the programming language that
6198 you are using.
6199
6200 With no argument, it does completion based on the current tags tables,
6201 just like the old binding of M-TAB (complete-tag).
6202
6203 ** File locking works with NFS now.
6204
6205 The lock file for FILENAME is now a symbolic link named .#FILENAME,
6206 in the same directory as FILENAME.
6207
6208 This means that collision detection between two different machines now
6209 works reasonably well; it also means that no file server or directory
6210 can become a bottleneck.
6211
6212 The new method does have drawbacks. It means that collision detection
6213 does not operate when you edit a file in a directory where you cannot
6214 create new files. Collision detection also doesn't operate when the
6215 file server does not support symbolic links. But these conditions are
6216 rare, and the ability to have collision detection while using NFS is
6217 so useful that the change is worth while.
6218
6219 When Emacs or a system crashes, this may leave behind lock files which
6220 are stale. So you may occasionally get warnings about spurious
6221 collisions. When you determine that the collision is spurious, just
6222 tell Emacs to go ahead anyway.
6223
6224 ** If you wish to use Show Paren mode to display matching parentheses,
6225 it is no longer sufficient to load paren.el. Instead you must call
6226 show-paren-mode.
6227
6228 ** If you wish to use Delete Selection mode to replace a highlighted
6229 selection when you insert new text, it is no longer sufficient to load
6230 delsel.el. Instead you must call the function delete-selection-mode.
6231
6232 ** If you wish to use Partial Completion mode to complete partial words
6233 within symbols or filenames, it is no longer sufficient to load
6234 complete.el. Instead you must call the function partial-completion-mode.
6235
6236 ** If you wish to use uniquify to rename buffers for you,
6237 it is no longer sufficient to load uniquify.el. You must also
6238 set uniquify-buffer-name-style to one of the non-nil legitimate values.
6239
6240 ** Changes in View mode.
6241
6242 *** Several new commands are available in View mode.
6243 Do H in view mode for a list of commands.
6244
6245 *** There are two new commands for entering View mode:
6246 view-file-other-frame and view-buffer-other-frame.
6247
6248 *** Exiting View mode does a better job of restoring windows to their
6249 previous state.
6250
6251 *** New customization variable view-scroll-auto-exit. If non-nil,
6252 scrolling past end of buffer makes view mode exit.
6253
6254 *** New customization variable view-exits-all-viewing-windows. If
6255 non-nil, view-mode will at exit restore all windows viewing buffer,
6256 not just the selected window.
6257
6258 *** New customization variable view-read-only. If non-nil, visiting a
6259 read-only file automatically enters View mode, and toggle-read-only
6260 turns View mode on or off.
6261
6262 *** New customization variable view-remove-frame-by-deleting controls
6263 how to remove a not needed frame at view mode exit. If non-nil,
6264 delete the frame, if nil make an icon of it.
6265
6266 ** C-x v l, the command to print a file's version control log,
6267 now positions point at the entry for the file's current branch version.
6268
6269 ** C-x v =, the command to compare a file with the last checked-in version,
6270 has a new feature. If the file is currently not locked, so that it is
6271 presumably identical to the last checked-in version, the command now asks
6272 which version to compare with.
6273
6274 ** When using hideshow.el, incremental search can temporarily show hidden
6275 blocks if a match is inside the block.
6276
6277 The block is hidden again if the search is continued and the next match
6278 is outside the block. By customizing the variable
6279 isearch-hide-immediately you can choose to hide all the temporarily
6280 shown blocks only when exiting from incremental search.
6281
6282 By customizing the variable hs-isearch-open you can choose what kind
6283 of blocks to temporarily show during isearch: comment blocks, code
6284 blocks, all of them or none.
6285
6286 ** The new command C-x 4 0 (kill-buffer-and-window) kills the
6287 current buffer and deletes the selected window. It asks for
6288 confirmation first.
6289
6290 ** C-x C-w, which saves the buffer into a specified file name,
6291 now changes the major mode according to that file name.
6292 However, the mode will not be changed if
6293 (1) a local variables list or the `-*-' line specifies a major mode, or
6294 (2) the current major mode is a "special" mode,
6295 not suitable for ordinary files, or
6296 (3) the new file name does not particularly specify any mode.
6297
6298 This applies to M-x set-visited-file-name as well.
6299
6300 However, if you set change-major-mode-with-file-name to nil, then
6301 these commands do not change the major mode.
6302
6303 ** M-x occur changes.
6304
6305 *** If the argument to M-x occur contains upper case letters,
6306 it performs a case-sensitive search.
6307
6308 *** In the *Occur* buffer made by M-x occur,
6309 if you type g or M-x revert-buffer, this repeats the search
6310 using the same regular expression and the same buffer as before.
6311
6312 ** In Transient Mark mode, the region in any one buffer is highlighted
6313 in just one window at a time. At first, it is highlighted in the
6314 window where you set the mark. The buffer's highlighting remains in
6315 that window unless you select to another window which shows the same
6316 buffer--then the highlighting moves to that window.
6317
6318 ** The feature to suggest key bindings when you use M-x now operates
6319 after the command finishes. The message suggesting key bindings
6320 appears temporarily in the echo area. The previous echo area contents
6321 come back after a few seconds, in case they contain useful information.
6322
6323 ** Each frame now independently records the order for recently
6324 selected buffers, so that the default for C-x b is now based on the
6325 buffers recently selected in the selected frame.
6326
6327 ** Outline mode changes.
6328
6329 *** Outline mode now uses overlays (this is the former noutline.el).
6330
6331 *** Incremental searches skip over invisible text in Outline mode.
6332
6333 ** When a minibuffer window is active but not the selected window, if
6334 you try to use the minibuffer, you used to get a nested minibuffer.
6335 Now, this not only gives an error, it also cancels the minibuffer that
6336 was already active.
6337
6338 The motive for this change is so that beginning users do not
6339 unknowingly move away from minibuffers, leaving them active, and then
6340 get confused by it.
6341
6342 If you want to be able to have recursive minibuffers, you must
6343 set enable-recursive-minibuffers to non-nil.
6344
6345 ** Changes in dynamic abbrevs.
6346
6347 *** Expanding dynamic abbrevs with M-/ is now smarter about case
6348 conversion. If the expansion has mixed case not counting the first
6349 character, and the abbreviation matches the beginning of the expansion
6350 including case, then the expansion is copied verbatim.
6351
6352 The expansion is also copied verbatim if the abbreviation itself has
6353 mixed case. And using SPC M-/ to copy an additional word always
6354 copies it verbatim except when the previous copied word is all caps.
6355
6356 *** The values of `dabbrev-case-replace' and `dabbrev-case-fold-search'
6357 are no longer Lisp expressions. They have simply three possible
6358 values.
6359
6360 `dabbrev-case-replace' has these three values: nil (don't preserve
6361 case), t (do), or `case-replace' (do like M-x query-replace).
6362 `dabbrev-case-fold-search' has these three values: nil (don't ignore
6363 case), t (do), or `case-fold-search' (do like search).
6364
6365 ** Minibuffer history lists are truncated automatically now to a
6366 certain length. The variable history-length specifies how long they
6367 can be. The default value is 30.
6368
6369 ** Changes in Mail mode.
6370
6371 *** The key C-x m no longer runs the `mail' command directly.
6372 Instead, it runs the command `compose-mail', which invokes the mail
6373 composition mechanism you have selected with the variable
6374 `mail-user-agent'. The default choice of user agent is
6375 `sendmail-user-agent', which gives behavior compatible with the old
6376 behavior.
6377
6378 C-x 4 m now runs compose-mail-other-window, and C-x 5 m runs
6379 compose-mail-other-frame.
6380
6381 *** While composing a reply to a mail message, from Rmail, you can use
6382 the command C-c C-r to cite just the region from the message you are
6383 replying to. This copies the text which is the selected region in the
6384 buffer that shows the original message.
6385
6386 *** The command C-c C-i inserts a file at the end of the message,
6387 with separator lines around the contents.
6388
6389 *** The command M-x expand-mail-aliases expands all mail aliases
6390 in suitable mail headers. Emacs automatically extracts mail alias
6391 definitions from your mail alias file (e.g., ~/.mailrc). You do not
6392 need to expand mail aliases yourself before sending mail.
6393
6394 *** New features in the mail-complete command.
6395
6396 **** The mail-complete command now inserts the user's full name,
6397 for local users or if that is known. The variable mail-complete-style
6398 controls the style to use, and whether to do this at all.
6399 Its values are like those of mail-from-style.
6400
6401 **** The variable mail-passwd-command lets you specify a shell command
6402 to run to fetch a set of password-entries that add to the ones in
6403 /etc/passwd.
6404
6405 **** The variable mail-passwd-file now specifies a list of files to read
6406 to get the list of user ids. By default, one file is used:
6407 /etc/passwd.
6408
6409 ** You can "quote" a file name to inhibit special significance of
6410 special syntax, by adding `/:' to the beginning. Thus, if you have a
6411 directory named `/foo:', you can prevent it from being treated as a
6412 reference to a remote host named `foo' by writing it as `/:/foo:'.
6413
6414 Emacs uses this new construct automatically when necessary, such as
6415 when you start it with a working directory whose name might otherwise
6416 be taken to be magic.
6417
6418 ** There is a new command M-x grep-find which uses find to select
6419 files to search through, and grep to scan them. The output is
6420 available in a Compile mode buffer, as with M-x grep.
6421
6422 M-x grep now uses the -e option if the grep program supports that.
6423 (-e prevents problems if the search pattern starts with a dash.)
6424
6425 ** In Dired, the & command now flags for deletion the files whose names
6426 suggest they are probably not needed in the long run.
6427
6428 In Dired, * is now a prefix key for mark-related commands.
6429
6430 new key dired.el binding old key
6431 ------- ---------------- -------
6432 * c dired-change-marks c
6433 * m dired-mark m
6434 * * dired-mark-executables * (binding deleted)
6435 * / dired-mark-directories / (binding deleted)
6436 * @ dired-mark-symlinks @ (binding deleted)
6437 * u dired-unmark u
6438 * DEL dired-unmark-backward DEL
6439 * ? dired-unmark-all-files M-C-?
6440 * ! dired-unmark-all-marks
6441 * % dired-mark-files-regexp % m
6442 * C-n dired-next-marked-file M-}
6443 * C-p dired-prev-marked-file M-{
6444
6445 ** Rmail changes.
6446
6447 *** When Rmail cannot convert your incoming mail into Babyl format, it
6448 saves the new mail in the file RMAILOSE.n, where n is an integer
6449 chosen to make a unique name. This way, Rmail will not keep crashing
6450 each time you run it.
6451
6452 *** In Rmail, the variable rmail-summary-line-count-flag now controls
6453 whether to include the line count in the summary. Non-nil means yes.
6454
6455 *** In Rmail summary buffers, d and C-d (the commands to delete
6456 messages) now take repeat counts as arguments. A negative argument
6457 means to move in the opposite direction.
6458
6459 *** In Rmail, the t command now takes an optional argument which lets
6460 you specify whether to show the message headers in full or pruned.
6461
6462 *** In Rmail, the new command w (rmail-output-body-to-file) writes
6463 just the body of the current message into a file, without the headers.
6464 It takes the file name from the message subject, by default, but you
6465 can edit that file name in the minibuffer before it is actually used
6466 for output.
6467
6468 ** Gnus changes.
6469
6470 *** nntp.el has been totally rewritten in an asynchronous fashion.
6471
6472 *** Article prefetching functionality has been moved up into
6473 Gnus.
6474
6475 *** Scoring can now be performed with logical operators like
6476 `and', `or', `not', and parent redirection.
6477
6478 *** Article washing status can be displayed in the
6479 article mode line.
6480
6481 *** gnus.el has been split into many smaller files.
6482
6483 *** Suppression of duplicate articles based on Message-ID.
6484
6485 (setq gnus-suppress-duplicates t)
6486
6487 *** New variables for specifying what score and adapt files
6488 are to be considered home score and adapt files. See
6489 `gnus-home-score-file' and `gnus-home-adapt-files'.
6490
6491 *** Groups can inherit group parameters from parent topics.
6492
6493 *** Article editing has been revamped and is now usable.
6494
6495 *** Signatures can be recognized in more intelligent fashions.
6496 See `gnus-signature-separator' and `gnus-signature-limit'.
6497
6498 *** Summary pick mode has been made to look more nn-like.
6499 Line numbers are displayed and the `.' command can be
6500 used to pick articles.
6501
6502 *** Commands for moving the .newsrc.eld from one server to
6503 another have been added.
6504
6505 `M-x gnus-change-server'
6506
6507 *** A way to specify that "uninteresting" fields be suppressed when
6508 generating lines in buffers.
6509
6510 *** Several commands in the group buffer can be undone with
6511 `M-C-_'.
6512
6513 *** Scoring can be done on words using the new score type `w'.
6514
6515 *** Adaptive scoring can be done on a Subject word-by-word basis:
6516
6517 (setq gnus-use-adaptive-scoring '(word))
6518
6519 *** Scores can be decayed.
6520
6521 (setq gnus-decay-scores t)
6522
6523 *** Scoring can be performed using a regexp on the Date header. The
6524 Date is normalized to compact ISO 8601 format first.
6525
6526 *** A new command has been added to remove all data on articles from
6527 the native server.
6528
6529 `M-x gnus-group-clear-data-on-native-groups'
6530
6531 *** A new command for reading collections of documents
6532 (nndoc with nnvirtual on top) has been added -- `M-C-d'.
6533
6534 *** Process mark sets can be pushed and popped.
6535
6536 *** A new mail-to-news backend makes it possible to post
6537 even when the NNTP server doesn't allow posting.
6538
6539 *** A new backend for reading searches from Web search engines
6540 (DejaNews, Alta Vista, InReference) has been added.
6541
6542 Use the `G w' command in the group buffer to create such
6543 a group.
6544
6545 *** Groups inside topics can now be sorted using the standard
6546 sorting functions, and each topic can be sorted independently.
6547
6548 See the commands under the `T S' submap.
6549
6550 *** Subsets of the groups can be sorted independently.
6551
6552 See the commands under the `G P' submap.
6553
6554 *** Cached articles can be pulled into the groups.
6555
6556 Use the `Y c' command.
6557
6558 *** Score files are now applied in a more reliable order.
6559
6560 *** Reports on where mail messages end up can be generated.
6561
6562 `M-x nnmail-split-history'
6563
6564 *** More hooks and functions have been added to remove junk
6565 from incoming mail before saving the mail.
6566
6567 See `nnmail-prepare-incoming-header-hook'.
6568
6569 *** The nnml mail backend now understands compressed article files.
6570
6571 *** To enable Gnus to read/post multi-lingual articles, you must execute
6572 the following code, for instance, in your .emacs.
6573
6574 (add-hook 'gnus-startup-hook 'gnus-mule-initialize)
6575
6576 Then, when you start Gnus, it will decode non-ASCII text automatically
6577 and show appropriate characters. (Note: if you are using gnus-mime
6578 from the SEMI package, formerly known as TM, you should NOT add this
6579 hook to gnus-startup-hook; gnus-mime has its own method of handling
6580 this issue.)
6581
6582 Since it is impossible to distinguish all coding systems
6583 automatically, you may need to specify a choice of coding system for a
6584 particular news group. This can be done by:
6585
6586 (gnus-mule-add-group NEWSGROUP 'CODING-SYSTEM)
6587
6588 Here NEWSGROUP should be a string which names a newsgroup or a tree
6589 of newsgroups. If NEWSGROUP is "XXX.YYY", all news groups under
6590 "XXX.YYY" (including "XXX.YYY.ZZZ") will use the specified coding
6591 system. CODING-SYSTEM specifies which coding system to use (for both
6592 for reading and posting).
6593
6594 CODING-SYSTEM can also be a cons cell of the form
6595 (READ-CODING-SYSTEM . POST-CODING-SYSTEM)
6596 Then READ-CODING-SYSTEM is used when you read messages from the
6597 newsgroups, while POST-CODING-SYSTEM is used when you post messages
6598 there.
6599
6600 Emacs knows the right coding systems for certain newsgroups by
6601 default. Here are some of these default settings:
6602
6603 (gnus-mule-add-group "fj" 'iso-2022-7)
6604 (gnus-mule-add-group "alt.chinese.text" 'hz-gb-2312)
6605 (gnus-mule-add-group "alt.hk" 'hz-gb-2312)
6606 (gnus-mule-add-group "alt.chinese.text.big5" 'cn-big5)
6607 (gnus-mule-add-group "soc.culture.vietnamese" '(nil . viqr))
6608
6609 When you reply by mail to an article, these settings are ignored;
6610 the mail is encoded according to sendmail-coding-system, as usual.
6611
6612 ** CC mode changes.
6613
6614 *** If you edit primarily one style of C (or C++, Objective-C, Java)
6615 code, you may want to make the CC Mode style variables have global
6616 values so that you can set them directly in your .emacs file. To do
6617 this, set c-style-variables-are-local-p to nil in your .emacs file.
6618 Note that this only takes effect if you do it *before* cc-mode.el is
6619 loaded.
6620
6621 If you typically edit more than one style of C (or C++, Objective-C,
6622 Java) code in a single Emacs session, you may want to make the CC Mode
6623 style variables have buffer local values. By default, all buffers
6624 share the same style variable settings; to make them buffer local, set
6625 c-style-variables-are-local-p to t in your .emacs file. Note that you
6626 must do this *before* CC Mode is loaded.
6627
6628 *** The new variable c-indentation-style holds the C style name
6629 of the current buffer.
6630
6631 *** The variable c-block-comments-indent-p has been deleted, because
6632 it is no longer necessary. C mode now handles all the supported styles
6633 of block comments, with no need to say which one you will use.
6634
6635 *** There is a new indentation style "python", which specifies the C
6636 style that the Python developers like.
6637
6638 *** There is a new c-cleanup-list option: brace-elseif-brace.
6639 This says to put ...} else if (...) {... on one line,
6640 just as brace-else-brace says to put ...} else {... on one line.
6641
6642 ** VC Changes [new]
6643
6644 ** In vc-retrieve-snapshot (C-x v r), if you don't specify a snapshot
6645 name, it retrieves the *latest* versions of all files in the current
6646 directory and its subdirectories (aside from files already locked).
6647
6648 This feature is useful if your RCS directory is a link to a common
6649 master directory, and you want to pick up changes made by other
6650 developers.
6651
6652 You can do the same thing for an individual file by typing C-u C-x C-q
6653 RET in a buffer visiting that file.
6654
6655 *** VC can now handle files under CVS that are being "watched" by
6656 other developers. Such files are made read-only by CVS. To get a
6657 writable copy, type C-x C-q in a buffer visiting such a file. VC then
6658 calls "cvs edit", which notifies the other developers of it.
6659
6660 *** vc-version-diff (C-u C-x v =) now suggests reasonable defaults for
6661 version numbers, based on the current state of the file.
6662
6663 ** Calendar changes.
6664
6665 A new function, list-holidays, allows you list holidays or subclasses
6666 of holidays for ranges of years. Related menu items allow you do this
6667 for the year of the selected date, or the following/previous years.
6668
6669 ** ps-print changes
6670
6671 There are some new user variables for customizing the page layout.
6672
6673 *** Paper size, paper orientation, columns
6674
6675 The variable `ps-paper-type' determines the size of paper ps-print
6676 formats for; it should contain one of the symbols:
6677 `a4' `a3' `letter' `legal' `letter-small' `tabloid'
6678 `ledger' `statement' `executive' `a4small' `b4' `b5'
6679 It defaults to `letter'.
6680 If you need other sizes, see the variable `ps-page-dimensions-database'.
6681
6682 The variable `ps-landscape-mode' determines the orientation
6683 of the printing on the page. nil, the default, means "portrait" mode,
6684 non-nil means "landscape" mode.
6685
6686 The variable `ps-number-of-columns' must be a positive integer.
6687 It determines the number of columns both in landscape and portrait mode.
6688 It defaults to 1.
6689
6690 *** Horizontal layout
6691
6692 The horizontal layout is determined by the variables
6693 `ps-left-margin', `ps-inter-column', and `ps-right-margin'.
6694 All are measured in points.
6695
6696 *** Vertical layout
6697
6698 The vertical layout is determined by the variables
6699 `ps-bottom-margin', `ps-top-margin', and `ps-header-offset'.
6700 All are measured in points.
6701
6702 *** Headers
6703
6704 If the variable `ps-print-header' is nil, no header is printed. Then
6705 `ps-header-offset' is not relevant and `ps-top-margin' represents the
6706 margin above the text.
6707
6708 If the variable `ps-print-header-frame' is non-nil, a gaudy
6709 framing box is printed around the header.
6710
6711 The contents of the header are determined by `ps-header-lines',
6712 `ps-show-n-of-n', `ps-left-header' and `ps-right-header'.
6713
6714 The height of the header is determined by `ps-header-line-pad',
6715 `ps-header-font-family', `ps-header-title-font-size' and
6716 `ps-header-font-size'.
6717
6718 *** Font managing
6719
6720 The variable `ps-font-family' determines which font family is to be
6721 used for ordinary text. Its value must be a key symbol in the alist
6722 `ps-font-info-database'. You can add other font families by adding
6723 elements to this alist.
6724
6725 The variable `ps-font-size' determines the size of the font
6726 for ordinary text. It defaults to 8.5 points.
6727
6728 ** hideshow changes.
6729
6730 *** now supports hiding of blocks of single line comments (like // for
6731 C++, ; for lisp).
6732
6733 *** Support for java-mode added.
6734
6735 *** When doing `hs-hide-all' it is now possible to also hide the comments
6736 in the file if `hs-hide-comments-when-hiding-all' is set.
6737
6738 *** The new function `hs-hide-initial-comment' hides the the comments at
6739 the beginning of the files. Finally those huge RCS logs don't stay in your
6740 way! This is run by default when entering the `hs-minor-mode'.
6741
6742 *** Now uses overlays instead of `selective-display', so is more
6743 robust and a lot faster.
6744
6745 *** A block beginning can span multiple lines.
6746
6747 *** The new variable `hs-show-hidden-short-form' if t, directs hideshow
6748 to show only the beginning of a block when it is hidden. See the
6749 documentation for more details.
6750
6751 ** Changes in Enriched mode.
6752
6753 *** When you visit a file in enriched-mode, Emacs will make sure it is
6754 filled to the current fill-column. This behavior is now independent
6755 of the size of the window. When you save the file, the fill-column in
6756 use is stored as well, so that the whole buffer need not be refilled
6757 the next time unless the fill-column is different.
6758
6759 *** use-hard-newlines is now a minor mode. When it is enabled, Emacs
6760 distinguishes between hard and soft newlines, and treats hard newlines
6761 as paragraph boundaries. Otherwise all newlines inserted are marked
6762 as soft, and paragraph boundaries are determined solely from the text.
6763
6764 ** Font Lock mode
6765
6766 *** Custom support
6767
6768 The variables font-lock-face-attributes, font-lock-display-type and
6769 font-lock-background-mode are now obsolete; the recommended way to specify the
6770 faces to use for Font Lock mode is with M-x customize-group on the new custom
6771 group font-lock-highlighting-faces. If you set font-lock-face-attributes in
6772 your ~/.emacs file, Font Lock mode will respect its value. However, you should
6773 consider converting from setting that variable to using M-x customize.
6774
6775 You can still use X resources to specify Font Lock face appearances.
6776
6777 *** Maximum decoration
6778
6779 Fontification now uses the maximum level of decoration supported by
6780 default. Previously, fontification used a mode-specific default level
6781 of decoration, which is typically the minimum level of decoration
6782 supported. You can set font-lock-maximum-decoration to nil
6783 to get the old behavior.
6784
6785 *** New support
6786
6787 Support is now provided for Java, Objective-C, AWK and SIMULA modes.
6788
6789 Note that Font Lock mode can be turned on without knowing exactly what modes
6790 support Font Lock mode, via the command global-font-lock-mode.
6791
6792 *** Configurable support
6793
6794 Support for C, C++, Objective-C and Java can be more easily configured for
6795 additional types and classes via the new variables c-font-lock-extra-types,
6796 c++-font-lock-extra-types, objc-font-lock-extra-types and, you guessed it,
6797 java-font-lock-extra-types. These value of each of these variables should be a
6798 list of regexps matching the extra type names. For example, the default value
6799 of c-font-lock-extra-types is ("\\sw+_t") which means fontification follows the
6800 convention that C type names end in _t. This results in slower fontification.
6801
6802 Of course, you can change the variables that specify fontification in whatever
6803 way you wish, typically by adding regexps. However, these new variables make
6804 it easier to make specific and common changes for the fontification of types.
6805
6806 *** Adding highlighting patterns to existing support
6807
6808 You can use the new function font-lock-add-keywords to add your own
6809 highlighting patterns, such as for project-local or user-specific constructs,
6810 for any mode.
6811
6812 For example, to highlight `FIXME:' words in C comments, put:
6813
6814 (font-lock-add-keywords 'c-mode '(("\\<FIXME:" 0 font-lock-warning-face t)))
6815
6816 in your ~/.emacs.
6817
6818 *** New faces
6819
6820 Font Lock now defines two new faces, font-lock-builtin-face and
6821 font-lock-warning-face. These are intended to highlight builtin keywords,
6822 distinct from a language's normal keywords, and objects that should be brought
6823 to user attention, respectively. Various modes now use these new faces.
6824
6825 *** Changes to fast-lock support mode
6826
6827 The fast-lock package, one of the two Font Lock support modes, can now process
6828 cache files silently. You can use the new variable fast-lock-verbose, in the
6829 same way as font-lock-verbose, to control this feature.
6830
6831 *** Changes to lazy-lock support mode
6832
6833 The lazy-lock package, one of the two Font Lock support modes, can now fontify
6834 according to the true syntactic context relative to other lines. You can use
6835 the new variable lazy-lock-defer-contextually to control this feature. If
6836 non-nil, changes to the buffer will cause subsequent lines in the buffer to be
6837 refontified after lazy-lock-defer-time seconds of idle time. If nil, then only
6838 the modified lines will be refontified; this is the same as the previous Lazy
6839 Lock mode behaviour and the behaviour of Font Lock mode.
6840
6841 This feature is useful in modes where strings or comments can span lines.
6842 For example, if a string or comment terminating character is deleted, then if
6843 this feature is enabled subsequent lines in the buffer will be correctly
6844 refontified to reflect their new syntactic context. Previously, only the line
6845 containing the deleted character would be refontified and you would have to use
6846 the command M-g M-g (font-lock-fontify-block) to refontify some lines.
6847
6848 As a consequence of this new feature, two other variables have changed:
6849
6850 Variable `lazy-lock-defer-driven' is renamed `lazy-lock-defer-on-scrolling'.
6851 Variable `lazy-lock-defer-time' can now only be a time, i.e., a number.
6852 Buffer modes for which on-the-fly deferral applies can be specified via the
6853 new variable `lazy-lock-defer-on-the-fly'.
6854
6855 If you set these variables in your ~/.emacs, then you may have to change those
6856 settings.
6857
6858 ** Ada mode changes.
6859
6860 *** There is now better support for using find-file.el with Ada mode.
6861 If you switch between spec and body, the cursor stays in the same
6862 procedure (modulo overloading). If a spec has no body file yet, but
6863 you try to switch to its body file, Ada mode now generates procedure
6864 stubs.
6865
6866 *** There are two new commands:
6867 - `ada-make-local' : invokes gnatmake on the current buffer
6868 - `ada-check-syntax' : check syntax of current buffer.
6869
6870 The user options `ada-compiler-make', `ada-make-options',
6871 `ada-language-version', `ada-compiler-syntax-check', and
6872 `ada-compile-options' are used within these commands.
6873
6874 *** Ada mode can now work with Outline minor mode. The outline level
6875 is calculated from the indenting, not from syntactic constructs.
6876 Outlining does not work if your code is not correctly indented.
6877
6878 *** The new function `ada-gnat-style' converts the buffer to the style of
6879 formatting used in GNAT. It places two blanks after a comment start,
6880 places one blank between a word end and an opening '(', and puts one
6881 space between a comma and the beginning of a word.
6882
6883 ** Scheme mode changes.
6884
6885 *** Scheme mode indentation now uses many of the facilities of Lisp
6886 mode; therefore, the variables to customize it are the variables used
6887 for Lisp mode which have names starting with `lisp-'. The variables
6888 with names starting with `scheme-' which used to do this no longer
6889 have any effect.
6890
6891 If you want to use different indentation for Scheme and Lisp, this is
6892 still possible, but now you must do it by adding a hook to
6893 scheme-mode-hook, which could work by setting the `lisp-' indentation
6894 variables as buffer-local variables.
6895
6896 *** DSSSL mode is a variant of Scheme mode, for editing DSSSL scripts.
6897 Use M-x dsssl-mode.
6898
6899 ** Changes to the emacsclient program
6900
6901 *** If a socket can't be found, and environment variables LOGNAME or
6902 USER are set, emacsclient now looks for a socket based on the UID
6903 associated with the name. That is an emacsclient running as root
6904 can connect to an Emacs server started by a non-root user.
6905
6906 *** The emacsclient program now accepts an option --no-wait which tells
6907 it to return immediately without waiting for you to "finish" the
6908 buffer in Emacs.
6909
6910 *** The new option --alternate-editor allows to specify an editor to
6911 use if Emacs is not running. The environment variable
6912 ALTERNATE_EDITOR can be used for the same effect; the command line
6913 option takes precedence.
6914
6915 ** M-x eldoc-mode enables a minor mode in which the echo area
6916 constantly shows the parameter list for function being called at point
6917 (in Emacs Lisp and Lisp Interaction modes only).
6918
6919 ** C-x n d now runs the new command narrow-to-defun,
6920 which narrows the accessible parts of the buffer to just
6921 the current defun.
6922
6923 ** Emacs now handles the `--' argument in the standard way; all
6924 following arguments are treated as ordinary file names.
6925
6926 ** On MSDOS and Windows, the bookmark file is now called _emacs.bmk,
6927 and the saved desktop file is now called _emacs.desktop (truncated if
6928 necessary).
6929
6930 ** When you kill a buffer that visits a file,
6931 if there are any registers that save positions in the file,
6932 these register values no longer become completely useless.
6933 If you try to go to such a register with C-x j, then you are
6934 asked whether to visit the file again. If you say yes,
6935 it visits the file and then goes to the same position.
6936
6937 ** When you visit a file that changes frequently outside Emacs--for
6938 example, a log of output from a process that continues to run--it may
6939 be useful for Emacs to revert the file without querying you whenever
6940 you visit the file afresh with C-x C-f.
6941
6942 You can request this behavior for certain files by setting the
6943 variable revert-without-query to a list of regular expressions. If a
6944 file's name matches any of these regular expressions, find-file and
6945 revert-buffer revert the buffer without asking for permission--but
6946 only if you have not edited the buffer text yourself.
6947
6948 ** set-default-font has been renamed to set-frame-font
6949 since it applies only to the current frame.
6950
6951 ** In TeX mode, you can use the variable tex-main-file to specify the
6952 file for tex-file to run TeX on. (By default, tex-main-file is nil,
6953 and tex-file runs TeX on the current visited file.)
6954
6955 This is useful when you are editing a document that consists of
6956 multiple files. In each of the included files, you can set up a local
6957 variable list which specifies the top-level file of your document for
6958 tex-main-file. Then tex-file will run TeX on the whole document
6959 instead of just the file you are editing.
6960
6961 ** RefTeX mode
6962
6963 RefTeX mode is a new minor mode with special support for \label, \ref
6964 and \cite macros in LaTeX documents. RefTeX distinguishes labels of
6965 different environments (equation, figure, ...) and has full support for
6966 multifile documents. To use it, select a buffer with a LaTeX document and
6967 turn the mode on with M-x reftex-mode. Here are the main user commands:
6968
6969 C-c ( reftex-label
6970 Creates a label semi-automatically. RefTeX is context sensitive and
6971 knows which kind of label is needed.
6972
6973 C-c ) reftex-reference
6974 Offers in a menu all labels in the document, along with context of the
6975 label definition. The selected label is referenced as \ref{LABEL}.
6976
6977 C-c [ reftex-citation
6978 Prompts for a regular expression and displays a list of matching BibTeX
6979 database entries. The selected entry is cited with a \cite{KEY} macro.
6980
6981 C-c & reftex-view-crossref
6982 Views the cross reference of a \ref or \cite command near point.
6983
6984 C-c = reftex-toc
6985 Shows a table of contents of the (multifile) document. From there you
6986 can quickly jump to every section.
6987
6988 Under X, RefTeX installs a "Ref" menu in the menu bar, with additional
6989 commands. Press `?' to get help when a prompt mentions this feature.
6990 Full documentation and customization examples are in the file
6991 reftex.el. You can use the finder to view the file documentation:
6992 C-h p --> tex --> reftex.el
6993
6994 ** Changes in BibTeX mode.
6995
6996 *** Info documentation is now available.
6997
6998 *** Don't allow parentheses in string constants anymore. This confused
6999 both the BibTeX program and Emacs BibTeX mode.
7000
7001 *** Renamed variable bibtex-mode-user-optional-fields to
7002 bibtex-user-optional-fields.
7003
7004 *** Removed variable bibtex-include-OPTannote
7005 (use bibtex-user-optional-fields instead).
7006
7007 *** New interactive functions to copy and kill fields and complete
7008 entries to the BibTeX kill ring, from where they can be yanked back by
7009 appropriate functions.
7010
7011 *** New interactive functions for repositioning and marking of
7012 entries. They are bound by default to M-C-l and M-C-h.
7013
7014 *** New hook bibtex-clean-entry-hook. It is called after entry has
7015 been cleaned.
7016
7017 *** New variable bibtex-field-delimiters, which replaces variables
7018 bibtex-field-{left|right}-delimiter.
7019
7020 *** New variable bibtex-entry-delimiters to determine how entries
7021 shall be delimited.
7022
7023 *** Allow preinitialization of fields. See documentation of
7024 bibtex-user-optional-fields, bibtex-entry-field-alist, and
7025 bibtex-include-OPTkey for details.
7026
7027 *** Book and InBook entries require either an author or an editor
7028 field. This is now supported by bibtex.el. Alternative fields are
7029 prefixed with `ALT'.
7030
7031 *** New variable bibtex-entry-format, which replaces variable
7032 bibtex-clean-entry-zap-empty-opts and allows specification of many
7033 formatting options performed on cleaning an entry (see variable
7034 documentation).
7035
7036 *** Even more control on how automatic keys are generated. See
7037 documentation of bibtex-generate-autokey for details. Transcriptions
7038 for foreign languages other than German are now handled, too.
7039
7040 *** New boolean user option bibtex-comma-after-last-field to decide if
7041 comma should be inserted at end of last field.
7042
7043 *** New boolean user option bibtex-align-at-equal-sign to determine if
7044 alignment should be made at left side of field contents or at equal
7045 signs. New user options to control entry layout (e.g. indentation).
7046
7047 *** New function bibtex-fill-entry to realign entries.
7048
7049 *** New function bibtex-reformat to reformat region or buffer.
7050
7051 *** New function bibtex-convert-alien to convert a BibTeX database
7052 from alien sources.
7053
7054 *** New function bibtex-complete-key (similar to bibtex-complete-string)
7055 to complete prefix to a key defined in buffer. Mainly useful in
7056 crossref entries.
7057
7058 *** New function bibtex-count-entries to count entries in buffer or
7059 region.
7060
7061 *** Added support for imenu.
7062
7063 *** The function `bibtex-validate' now checks current region instead
7064 of buffer if mark is active. Now it shows all errors of buffer in a
7065 `compilation mode' buffer. You can use the normal commands (e.g.
7066 `next-error') for compilation modes to jump to errors.
7067
7068 *** New variable `bibtex-string-file-path' to determine where the files
7069 from `bibtex-string-files' are searched.
7070
7071 ** Iso Accents mode now supports Latin-3 as an alternative.
7072
7073 ** The command next-error now opens blocks hidden by hideshow.
7074
7075 ** The function using-unix-filesystems has been replaced by the
7076 functions add-untranslated-filesystem and remove-untranslated-filesystem.
7077 Each of these functions takes the name of a drive letter or directory
7078 as an argument.
7079
7080 When a filesystem is added as untranslated, all files on it are read
7081 and written in binary mode (no cr/lf translation is performed).
7082
7083 ** browse-url changes
7084
7085 *** New methods for: Grail (browse-url-generic), MMM (browse-url-mmm),
7086 Lynx in a separate xterm (browse-url-lynx-xterm) or in an Emacs window
7087 (browse-url-lynx-emacs), remote W3 (browse-url-w3-gnudoit), generic
7088 non-remote-controlled browsers (browse-url-generic) and associated
7089 customization variables.
7090
7091 *** New commands `browse-url-of-region' and `browse-url'.
7092
7093 *** URLs marked up with <URL:...> (RFC1738) work if broken across
7094 lines. Browsing methods can be associated with URL regexps
7095 (e.g. mailto: URLs) via `browse-url-browser-function'.
7096
7097 ** Changes in Ediff
7098
7099 *** Clicking Mouse-2 on a brief command description in Ediff control panel
7100 pops up the Info file for this command.
7101
7102 *** There is now a variable, ediff-autostore-merges, which controls whether
7103 the result of a merge is saved in a file. By default, this is done only when
7104 merge is done from a session group (eg, when merging files in two different
7105 directories).
7106
7107 *** Since Emacs 19.31 (this hasn't been announced before), Ediff can compare
7108 and merge groups of files residing in different directories, or revisions of
7109 files in the same directory.
7110
7111 *** Since Emacs 19.31, Ediff can apply multi-file patches interactively.
7112 The patches must be in the context format or GNU unified format. (The bug
7113 related to the GNU format has now been fixed.)
7114
7115 ** Changes in Viper
7116
7117 *** The startup file is now .viper instead of .vip
7118 *** All variable/function names have been changed to start with viper-
7119 instead of vip-.
7120 *** C-\ now simulates the meta-key in all Viper states.
7121 *** C-z in Insert state now escapes to Vi for the duration of the next
7122 Viper command. In Vi and Insert states, C-z behaves as before.
7123 *** C-c \ escapes to Vi for one command if Viper is in Insert or Emacs states.
7124 *** _ is no longer the meta-key in Vi state.
7125 *** The variable viper-insert-state-cursor-color can be used to change cursor
7126 color when Viper is in insert state.
7127 *** If search lands the cursor near the top or the bottom of the window,
7128 Viper pulls the window up or down to expose more context. The variable
7129 viper-adjust-window-after-search controls this behavior.
7130
7131 ** Etags changes.
7132
7133 *** In C, C++, Objective C and Java, Etags tags global variables by
7134 default. The resulting tags files are inflated by 30% on average.
7135 Use --no-globals to turn this feature off. Etags can also tag
7136 variables which are members of structure-like constructs, but it does
7137 not by default. Use --members to turn this feature on.
7138
7139 *** C++ member functions are now recognized as tags.
7140
7141 *** Java is tagged like C++. In addition, "extends" and "implements"
7142 constructs are tagged. Files are recognised by the extension .java.
7143
7144 *** Etags can now handle programs written in Postscript. Files are
7145 recognised by the extensions .ps and .pdb (Postscript with C syntax).
7146 In Postscript, tags are lines that start with a slash.
7147
7148 *** Etags now handles Objective C and Objective C++ code. The usual C and
7149 C++ tags are recognized in these languages; in addition, etags
7150 recognizes special Objective C syntax for classes, class categories,
7151 methods and protocols.
7152
7153 *** Etags also handles Cobol. Files are recognised by the extension
7154 .cobol. The tagged lines are those containing a word that begins in
7155 column 8 and ends in a full stop, i.e. anything that could be a
7156 paragraph name.
7157
7158 *** Regexps in Etags now support intervals, as in ed or grep. The syntax of
7159 an interval is \{M,N\}, and it means to match the preceding expression
7160 at least M times and as many as N times.
7161
7162 ** The format for specifying a custom format for time-stamp to insert
7163 in files has changed slightly.
7164
7165 With the new enhancements to the functionality of format-time-string,
7166 time-stamp-format will change to be eventually compatible with it.
7167 This conversion is being done in two steps to maintain compatibility
7168 with old time-stamp-format values.
7169
7170 In the new scheme, alternate case is signified by the number-sign
7171 (`#') modifier, rather than changing the case of the format character.
7172 This feature is as yet incompletely implemented for compatibility
7173 reasons.
7174
7175 In the old time-stamp-format, all numeric fields defaulted to their
7176 natural width. (With format-time-string, each format has a
7177 fixed-width default.) In this version, you can specify the colon
7178 (`:') modifier to a numeric conversion to mean "give me the historical
7179 time-stamp-format width default." Do not use colon if you are
7180 specifying an explicit width, as in "%02d".
7181
7182 Numbers are no longer truncated to the requested width, except in the
7183 case of "%02y", which continues to give a two-digit year. Digit
7184 truncation probably wasn't being used for anything else anyway.
7185
7186 The new formats will work with old versions of Emacs. New formats are
7187 being recommended now to allow time-stamp-format to change in the
7188 future to be compatible with format-time-string. The new forms being
7189 recommended now will continue to work then.
7190
7191 See the documentation string for the variable time-stamp-format for
7192 details.
7193
7194 ** There are some additional major modes:
7195
7196 dcl-mode, for editing VMS DCL files.
7197 m4-mode, for editing files of m4 input.
7198 meta-mode, for editing MetaFont and MetaPost source files.
7199
7200 ** In Shell mode, the command shell-copy-environment-variable lets you
7201 copy the value of a specified environment variable from the subshell
7202 into Emacs.
7203
7204 ** New Lisp packages include:
7205
7206 *** battery.el displays battery status for laptops.
7207
7208 *** M-x bruce (named after Lenny Bruce) is a program that might
7209 be used for adding some indecent words to your email.
7210
7211 *** M-x crisp-mode enables an emulation for the CRiSP editor.
7212
7213 *** M-x dirtrack arranges for better tracking of directory changes
7214 in shell buffers.
7215
7216 *** The new library elint.el provides for linting of Emacs Lisp code.
7217 See the documentation for `elint-initialize', `elint-current-buffer'
7218 and `elint-defun'.
7219
7220 *** M-x expand-add-abbrevs defines a special kind of abbrev which is
7221 meant for programming constructs. These abbrevs expand like ordinary
7222 ones, when you type SPC, but only at the end of a line and not within
7223 strings or comments.
7224
7225 These abbrevs can act as templates: you can define places within an
7226 abbrev for insertion of additional text. Once you expand the abbrev,
7227 you can then use C-x a p and C-x a n to move back and forth to these
7228 insertion points. Thus you can conveniently insert additional text
7229 at these points.
7230
7231 *** filecache.el remembers the location of files so that you
7232 can visit them by short forms of their names.
7233
7234 *** find-func.el lets you find the definition of the user-loaded
7235 Emacs Lisp function at point.
7236
7237 *** M-x handwrite converts text to a "handwritten" picture.
7238
7239 *** M-x iswitchb-buffer is a command for switching to a buffer, much like
7240 switch-buffer, but it reads the argument in a more helpful way.
7241
7242 *** M-x landmark implements a neural network for landmark learning.
7243
7244 *** M-x locate provides a convenient interface to the `locate' program.
7245
7246 *** M4 mode is a new mode for editing files of m4 input.
7247
7248 *** mantemp.el creates C++ manual template instantiations
7249 from the GCC error messages which indicate which instantiations are needed.
7250
7251 *** mouse-copy.el provides a one-click copy and move feature.
7252 You can drag a region with M-mouse-1, and it is automatically
7253 inserted at point. M-Shift-mouse-1 deletes the text from its
7254 original place after inserting the copy.
7255
7256 *** mouse-drag.el lets you do scrolling by dragging Mouse-2
7257 on the buffer.
7258
7259 You click the mouse and move; that distance either translates into the
7260 velocity to scroll (with mouse-drag-throw) or the distance to scroll
7261 (with mouse-drag-drag). Horizontal scrolling is enabled when needed.
7262
7263 Enable mouse-drag with:
7264 (global-set-key [down-mouse-2] 'mouse-drag-throw)
7265 -or-
7266 (global-set-key [down-mouse-2] 'mouse-drag-drag)
7267
7268 *** mspools.el is useful for determining which mail folders have
7269 mail waiting to be read in them. It works with procmail.
7270
7271 *** Octave mode is a major mode for editing files of input for Octave.
7272 It comes with a facility for communicating with an Octave subprocess.
7273
7274 *** ogonek
7275
7276 The ogonek package provides functions for changing the coding of
7277 Polish diacritic characters in buffers. Codings known from various
7278 platforms are supported such as ISO8859-2, Mazovia, IBM Latin2, and
7279 TeX. For example, you can change the coding from Mazovia to
7280 ISO8859-2. Another example is a change of coding from ISO8859-2 to
7281 prefix notation (in which `/a' stands for the aogonek character, for
7282 instance) and vice versa.
7283
7284 To use this package load it using
7285 M-x load-library [enter] ogonek
7286 Then, you may get an explanation by calling one of
7287 M-x ogonek-jak -- in Polish
7288 M-x ogonek-how -- in English
7289 The info specifies the commands and variables provided as well as the
7290 ways of customization in `.emacs'.
7291
7292 *** Interface to ph.
7293
7294 Emacs provides a client interface to CCSO Nameservers (ph/qi)
7295
7296 The CCSO nameserver is used in many universities to provide directory
7297 services about people. ph.el provides a convenient Emacs interface to
7298 these servers.
7299
7300 *** uce.el is useful for replying to unsolicited commercial email.
7301
7302 *** vcursor.el implements a "virtual cursor" feature.
7303 You can move the virtual cursor with special commands
7304 while the real cursor does not move.
7305
7306 *** webjump.el is a "hot list" package which you can set up
7307 for visiting your favorite web sites.
7308
7309 *** M-x winner-mode is a minor mode which saves window configurations,
7310 so you can move back to other configurations that you have recently used.
7311
7312 ** movemail change
7313
7314 Movemail no longer needs to be installed setuid root in order for POP
7315 mail retrieval to function properly. This is because it no longer
7316 supports the RPOP (reserved-port POP) protocol; instead, it uses the
7317 user's POP password to authenticate to the mail server.
7318
7319 This change was made earlier, but not reported in NEWS before.
7320 \f
7321 * Emacs 20.1 changes for MS-DOS and MS-Windows.
7322
7323 ** Changes in handling MS-DOS/MS-Windows text files.
7324
7325 Emacs handles three different conventions for representing
7326 end-of-line: CRLF for MSDOS, LF for Unix and GNU, and CR (used on the
7327 Macintosh). Emacs determines which convention is used in a specific
7328 file based on the contents of that file (except for certain special
7329 file names), and when it saves the file, it uses the same convention.
7330
7331 To save the file and change the end-of-line convention, you can use
7332 C-x RET f (set-buffer-file-coding-system) to specify a different
7333 coding system for the buffer. Then, when you save the file, the newly
7334 specified coding system will take effect. For example, to save with
7335 LF, specify undecided-unix (or some other ...-unix coding system); to
7336 save with CRLF, specify undecided-dos.
7337 \f
7338 * Lisp Changes in Emacs 20.1
7339
7340 ** Byte-compiled files made with Emacs 20 will, in general, work in
7341 Emacs 19 as well, as long as the source code runs in Emacs 19. And
7342 vice versa: byte-compiled files made with Emacs 19 should also run in
7343 Emacs 20, as long as the program itself works in Emacs 20.
7344
7345 ** Windows-specific functions and variables have been renamed
7346 to start with w32- instead of win32-.
7347
7348 In hacker language, calling something a "win" is a form of praise. We
7349 don't want to praise a non-free Microsoft system, so we don't call it
7350 "win".
7351
7352 ** Basic Lisp changes
7353
7354 *** A symbol whose name starts with a colon now automatically
7355 evaluates to itself. Therefore such a symbol can be used as a constant.
7356
7357 *** The defined purpose of `defconst' has been changed. It should now
7358 be used only for values that should not be changed whether by a program
7359 or by the user.
7360
7361 The actual behavior of defconst has not been changed.
7362
7363 *** There are new macros `when' and `unless'
7364
7365 (when CONDITION BODY...) is short for (if CONDITION (progn BODY...))
7366 (unless CONDITION BODY...) is short for (if CONDITION nil BODY...)
7367
7368 *** Emacs now defines functions caar, cadr, cdar and cddr with their
7369 usual Lisp meanings. For example, caar returns the car of the car of
7370 its argument.
7371
7372 *** equal, when comparing strings, now ignores their text properties.
7373
7374 *** The new function `functionp' tests whether an object is a function.
7375
7376 *** arrayp now returns t for char-tables and bool-vectors.
7377
7378 *** Certain primitives which use characters (as integers) now get an
7379 error if the integer is not a valid character code. These primitives
7380 include insert-char, char-to-string, and the %c construct in the
7381 `format' function.
7382
7383 *** The `require' function now insists on adding a suffix, either .el
7384 or .elc, to the file name. Thus, (require 'foo) will not use a file
7385 whose name is just foo. It insists on foo.el or foo.elc.
7386
7387 *** The `autoload' function, when the file name does not contain
7388 either a directory name or the suffix .el or .elc, insists on
7389 adding one of these suffixes.
7390
7391 *** string-to-number now takes an optional second argument BASE
7392 which specifies the base to use when converting an integer.
7393 If BASE is omitted, base 10 is used.
7394
7395 We have not implemented other radices for floating point numbers,
7396 because that would be much more work and does not seem useful.
7397
7398 *** substring now handles vectors as well as strings.
7399
7400 *** The Common Lisp function eql is no longer defined normally.
7401 You must load the `cl' library to define it.
7402
7403 *** The new macro `with-current-buffer' lets you evaluate an expression
7404 conveniently with a different current buffer. It looks like this:
7405
7406 (with-current-buffer BUFFER BODY-FORMS...)
7407
7408 BUFFER is the expression that says which buffer to use.
7409 BODY-FORMS say what to do in that buffer.
7410
7411 *** The new primitive `save-current-buffer' saves and restores the
7412 choice of current buffer, like `save-excursion', but without saving or
7413 restoring the value of point or the mark. `with-current-buffer'
7414 works using `save-current-buffer'.
7415
7416 *** The new macro `with-temp-file' lets you do some work in a new buffer and
7417 write the output to a specified file. Like `progn', it returns the value
7418 of the last form.
7419
7420 *** The new macro `with-temp-buffer' lets you do some work in a new buffer,
7421 which is discarded after use. Like `progn', it returns the value of the
7422 last form. If you wish to return the buffer contents, use (buffer-string)
7423 as the last form.
7424
7425 *** The new function split-string takes a string, splits it at certain
7426 characters, and returns a list of the substrings in between the
7427 matches.
7428
7429 For example, (split-string "foo bar lose" " +") returns ("foo" "bar" "lose").
7430
7431 *** The new macro with-output-to-string executes some Lisp expressions
7432 with standard-output set up so that all output feeds into a string.
7433 Then it returns that string.
7434
7435 For example, if the current buffer name is `foo',
7436
7437 (with-output-to-string
7438 (princ "The buffer is ")
7439 (princ (buffer-name)))
7440
7441 returns "The buffer is foo".
7442
7443 ** Non-ASCII characters are now supported, if enable-multibyte-characters
7444 is non-nil.
7445
7446 These characters have character codes above 256. When inserted in the
7447 buffer or stored in a string, they are represented as multibyte
7448 characters that occupy several buffer positions each.
7449
7450 *** When enable-multibyte-characters is non-nil, a single character in
7451 a buffer or string can be two or more bytes (as many as four).
7452
7453 Buffers and strings are still made up of unibyte elements;
7454 character positions and string indices are always measured in bytes.
7455 Therefore, moving forward one character can increase the buffer
7456 position by 2, 3 or 4. The function forward-char moves by whole
7457 characters, and therefore is no longer equivalent to
7458 (lambda (n) (goto-char (+ (point) n))).
7459
7460 ASCII characters (codes 0 through 127) are still single bytes, always.
7461 Sequences of byte values 128 through 255 are used to represent
7462 non-ASCII characters. These sequences are called "multibyte
7463 characters".
7464
7465 The first byte of a multibyte character is always in the range 128
7466 through 159 (octal 0200 through 0237). These values are called
7467 "leading codes". The second and subsequent bytes are always in the
7468 range 160 through 255 (octal 0240 through 0377). The first byte, the
7469 leading code, determines how many bytes long the sequence is.
7470
7471 *** The function forward-char moves over characters, and therefore
7472 (forward-char 1) may increase point by more than 1 if it moves over a
7473 multibyte character. Likewise, delete-char always deletes a
7474 character, which may be more than one buffer position.
7475
7476 This means that some Lisp programs, which assume that a character is
7477 always one buffer position, need to be changed.
7478
7479 However, all ASCII characters are always one buffer position.
7480
7481 *** The regexp [\200-\377] no longer matches all non-ASCII characters,
7482 because when enable-multibyte-characters is non-nil, these characters
7483 have codes that are not in the range octal 200 to octal 377. However,
7484 the regexp [^\000-\177] does match all non-ASCII characters,
7485 guaranteed.
7486
7487 *** The function char-boundary-p returns non-nil if position POS is
7488 between two characters in the buffer (not in the middle of a
7489 character).
7490
7491 When the value is non-nil, it says what kind of character follows POS:
7492
7493 0 if POS is at an ASCII character or at the end of range,
7494 1 if POS is before a 2-byte length multi-byte form,
7495 2 if POS is at a head of 3-byte length multi-byte form,
7496 3 if POS is at a head of 4-byte length multi-byte form,
7497 4 if POS is at a head of multi-byte form of a composite character.
7498
7499 *** The function char-bytes returns how many bytes the character CHAR uses.
7500
7501 *** Strings can contain multibyte characters. The function
7502 `length' returns the string length counting bytes, which may be
7503 more than the number of characters.
7504
7505 You can include a multibyte character in a string constant by writing
7506 it literally. You can also represent it with a hex escape,
7507 \xNNNNNNN..., using as many digits as necessary. Any character which
7508 is not a valid hex digit terminates this construct. If you want to
7509 follow it with a character that is a hex digit, write backslash and
7510 newline in between; that will terminate the hex escape.
7511
7512 *** The function concat-chars takes arguments which are characters
7513 and returns a string containing those characters.
7514
7515 *** The function sref access a multibyte character in a string.
7516 (sref STRING INDX) returns the character in STRING at INDEX. INDEX
7517 counts from zero. If INDEX is at a position in the middle of a
7518 character, sref signals an error.
7519
7520 *** The function chars-in-string returns the number of characters
7521 in a string. This is less than the length of the string, if the
7522 string contains multibyte characters (the length counts bytes).
7523
7524 *** The function chars-in-region returns the number of characters
7525 in a region from BEG to END. This is less than (- END BEG) if the
7526 region contains multibyte characters (the length counts bytes).
7527
7528 *** The function string-to-list converts a string to a list of
7529 the characters in it. string-to-vector converts a string
7530 to a vector of the characters in it.
7531
7532 *** The function store-substring alters part of the contents
7533 of a string. You call it as follows:
7534
7535 (store-substring STRING IDX OBJ)
7536
7537 This says to alter STRING, by storing OBJ starting at index IDX in
7538 STRING. OBJ may be either a character or a (smaller) string.
7539 This function really does alter the contents of STRING.
7540 Since it is impossible to change the length of an existing string,
7541 it is an error if OBJ doesn't fit within STRING's actual length.
7542
7543 *** char-width returns the width (in columns) of the character CHAR,
7544 if it were displayed in the current buffer and the selected window.
7545
7546 *** string-width returns the width (in columns) of the text in STRING,
7547 if it were displayed in the current buffer and the selected window.
7548
7549 *** truncate-string-to-width shortens a string, if necessary,
7550 to fit within a certain number of columns. (Of course, it does
7551 not alter the string that you give it; it returns a new string
7552 which contains all or just part of the existing string.)
7553
7554 (truncate-string-to-width STR END-COLUMN &optional START-COLUMN PADDING)
7555
7556 This returns the part of STR up to column END-COLUMN.
7557
7558 The optional argument START-COLUMN specifies the starting column.
7559 If this is non-nil, then the first START-COLUMN columns of the string
7560 are not included in the resulting value.
7561
7562 The optional argument PADDING, if non-nil, is a padding character to be added
7563 at the beginning and end the resulting string, to extend it to exactly
7564 WIDTH columns. If PADDING is nil, that means do not pad; then, if STRING
7565 is narrower than WIDTH, the value is equal to STRING.
7566
7567 If PADDING and START-COLUMN are both non-nil, and if there is no clean
7568 place in STRING that corresponds to START-COLUMN (because one
7569 character extends across that column), then the padding character
7570 PADDING is added one or more times at the beginning of the result
7571 string, so that its columns line up as if it really did start at
7572 column START-COLUMN.
7573
7574 *** When the functions in the list after-change-functions are called,
7575 the third argument is the number of bytes in the pre-change text, not
7576 necessarily the number of characters. It is, in effect, the
7577 difference in buffer position between the beginning and the end of the
7578 changed text, before the change.
7579
7580 *** The characters Emacs uses are classified in various character
7581 sets, each of which has a name which is a symbol. In general there is
7582 one character set for each script, not for each language.
7583
7584 **** The function charsetp tests whether an object is a character set name.
7585
7586 **** The variable charset-list holds a list of character set names.
7587
7588 **** char-charset, given a character code, returns the name of the character
7589 set that the character belongs to. (The value is a symbol.)
7590
7591 **** split-char, given a character code, returns a list containing the
7592 name of the character set, followed by one or two byte-values
7593 which identify the character within that character set.
7594
7595 **** make-char, given a character set name and one or two subsequent
7596 byte-values, constructs a character code. This is roughly the
7597 opposite of split-char.
7598
7599 **** find-charset-region returns a list of the character sets
7600 of all the characters between BEG and END.
7601
7602 **** find-charset-string returns a list of the character sets
7603 of all the characters in a string.
7604
7605 *** Here are the Lisp facilities for working with coding systems
7606 and specifying coding systems.
7607
7608 **** The function coding-system-list returns a list of all coding
7609 system names (symbols). With optional argument t, it returns a list
7610 of all distinct base coding systems, not including variants.
7611 (Variant coding systems are those like latin-1-dos, latin-1-unix
7612 and latin-1-mac which specify the end-of-line conversion as well
7613 as what to do about code conversion.)
7614
7615 **** coding-system-p tests a symbol to see if it is a coding system
7616 name. It returns t if so, nil if not.
7617
7618 **** file-coding-system-alist specifies which coding systems to use
7619 for certain file names. It works like network-coding-system-alist,
7620 except that the PATTERN is matched against the file name.
7621
7622 Each element has the format (PATTERN . VAL), where PATTERN determines
7623 which file names the element applies to. PATTERN should be a regexp
7624 to match against a file name.
7625
7626 VAL is a coding system, a cons cell containing two coding systems, or
7627 a function symbol. If VAL is a coding system, it is used for both
7628 decoding what received from the network stream and encoding what sent
7629 to the network stream. If VAL is a cons cell containing two coding
7630 systems, the car specifies the coding system for decoding, and the cdr
7631 specifies the coding system for encoding.
7632
7633 If VAL is a function symbol, the function must return a coding system
7634 or a cons cell containing two coding systems, which is used as above.
7635
7636 **** The variable network-coding-system-alist specifies
7637 the coding system to use for network sockets.
7638
7639 Each element has the format (PATTERN . VAL), where PATTERN determines
7640 which network sockets the element applies to. PATTERN should be
7641 either a port number or a regular expression matching some network
7642 service names.
7643
7644 VAL is a coding system, a cons cell containing two coding systems, or
7645 a function symbol. If VAL is a coding system, it is used for both
7646 decoding what received from the network stream and encoding what sent
7647 to the network stream. If VAL is a cons cell containing two coding
7648 systems, the car specifies the coding system for decoding, and the cdr
7649 specifies the coding system for encoding.
7650
7651 If VAL is a function symbol, the function must return a coding system
7652 or a cons cell containing two coding systems, which is used as above.
7653
7654 **** process-coding-system-alist specifies which coding systems to use
7655 for certain subprocess. It works like network-coding-system-alist,
7656 except that the PATTERN is matched against the program name used to
7657 start the subprocess.
7658
7659 **** The variable default-process-coding-system specifies the coding
7660 systems to use for subprocess (and net connection) input and output,
7661 when nothing else specifies what to do. The value is a cons cell
7662 (OUTPUT-CODING . INPUT-CODING). OUTPUT-CODING applies to output
7663 to the subprocess, and INPUT-CODING applies to input from it.
7664
7665 **** The variable coding-system-for-write, if non-nil, specifies the
7666 coding system to use for writing a file, or for output to a synchronous
7667 subprocess.
7668
7669 It also applies to any asynchronous subprocess or network connection,
7670 but in a different way: the value of coding-system-for-write when you
7671 start the subprocess or connection affects that subprocess or
7672 connection permanently or until overridden.
7673
7674 The variable coding-system-for-write takes precedence over
7675 file-coding-system-alist, process-coding-system-alist and
7676 network-coding-system-alist, and all other methods of specifying a
7677 coding system for output. But most of the time this variable is nil.
7678 It exists so that Lisp programs can bind it to a specific coding
7679 system for one operation at a time.
7680
7681 **** coding-system-for-read applies similarly to input from
7682 files, subprocesses or network connections.
7683
7684 **** The function process-coding-system tells you what
7685 coding systems(s) an existing subprocess is using.
7686 The value is a cons cell,
7687 (DECODING-CODING-SYSTEM . ENCODING-CODING-SYSTEM)
7688 where DECODING-CODING-SYSTEM is used for decoding output from
7689 the subprocess, and ENCODING-CODING-SYSTEM is used for encoding
7690 input to the subprocess.
7691
7692 **** The function set-process-coding-system can be used to
7693 change the coding systems in use for an existing subprocess.
7694
7695 ** Emacs has a new facility to help users manage the many
7696 customization options. To make a Lisp program work with this facility,
7697 you need to use the new macros defgroup and defcustom.
7698
7699 You use defcustom instead of defvar, for defining a user option
7700 variable. The difference is that you specify two additional pieces of
7701 information (usually): the "type" which says what values are
7702 legitimate, and the "group" which specifies the hierarchy for
7703 customization.
7704
7705 Thus, instead of writing
7706
7707 (defvar foo-blurgoze nil
7708 "*Non-nil means that foo will act very blurgozely.")
7709
7710 you would now write this:
7711
7712 (defcustom foo-blurgoze nil
7713 "*Non-nil means that foo will act very blurgozely."
7714 :type 'boolean
7715 :group foo)
7716
7717 The type `boolean' means that this variable has only
7718 two meaningful states: nil and non-nil. Other type values
7719 describe other possibilities; see the manual for Custom
7720 for a description of them.
7721
7722 The "group" argument is used to specify a group which the option
7723 should belong to. You define a new group like this:
7724
7725 (defgroup ispell nil
7726 "Spell checking using Ispell."
7727 :group 'processes)
7728
7729 The "group" argument in defgroup specifies the parent group. The root
7730 group is called `emacs'; it should not contain any variables itself,
7731 but only other groups. The immediate subgroups of `emacs' correspond
7732 to the keywords used by C-h p. Under these subgroups come
7733 second-level subgroups that belong to individual packages.
7734
7735 Each Emacs package should have its own set of groups. A simple
7736 package should have just one group; a more complex package should
7737 have a hierarchy of its own groups. The sole or root group of a
7738 package should be a subgroup of one or more of the "keyword"
7739 first-level subgroups.
7740
7741 ** New `widget' library for inserting UI components in buffers.
7742
7743 This library, used by the new custom library, is documented in a
7744 separate manual that accompanies Emacs.
7745
7746 ** easy-mmode
7747
7748 The easy-mmode package provides macros and functions that make
7749 developing minor modes easier. Roughly, the programmer has to code
7750 only the functionality of the minor mode. All the rest--toggles,
7751 predicate, and documentation--can be done in one call to the macro
7752 `easy-mmode-define-minor-mode' (see the documentation). See also
7753 `easy-mmode-define-keymap'.
7754
7755 ** Text property changes
7756
7757 *** The `intangible' property now works on overlays as well as on a
7758 text property.
7759
7760 *** The new functions next-char-property-change and
7761 previous-char-property-change scan through the buffer looking for a
7762 place where either a text property or an overlay might change. The
7763 functions take two arguments, POSITION and LIMIT. POSITION is the
7764 starting position for the scan. LIMIT says where to stop the scan.
7765
7766 If no property change is found before LIMIT, the value is LIMIT. If
7767 LIMIT is nil, scan goes to the beginning or end of the accessible part
7768 of the buffer. If no property change is found, the value is the
7769 position of the beginning or end of the buffer.
7770
7771 *** In the `local-map' text property or overlay property, the property
7772 value can now be a symbol whose function definition is a keymap. This
7773 is an alternative to using the keymap itself.
7774
7775 ** Changes in invisibility features
7776
7777 *** Isearch can now temporarily show parts of the buffer which are
7778 hidden by an overlay with a invisible property, when the search match
7779 is inside that portion of the buffer. To enable this the overlay
7780 should have a isearch-open-invisible property which is a function that
7781 would be called having the overlay as an argument, the function should
7782 make the overlay visible.
7783
7784 During incremental search the overlays are shown by modifying the
7785 invisible and intangible properties, if beside this more actions are
7786 needed the overlay should have a isearch-open-invisible-temporary
7787 which is a function. The function is called with 2 arguments: one is
7788 the overlay and the second is nil when it should show the overlay and
7789 t when it should hide it.
7790
7791 *** add-to-invisibility-spec, remove-from-invisibility-spec
7792
7793 Modes that use overlays to hide portions of a buffer should set the
7794 invisible property of the overlay to the mode's name (or another symbol)
7795 and modify the `buffer-invisibility-spec' to include that symbol.
7796 Use `add-to-invisibility-spec' and `remove-from-invisibility-spec' to
7797 manipulate the `buffer-invisibility-spec'.
7798 Here is an example of how to do this:
7799
7800 ;; If we want to display an ellipsis:
7801 (add-to-invisibility-spec '(my-symbol . t))
7802 ;; If you don't want ellipsis:
7803 (add-to-invisibility-spec 'my-symbol)
7804
7805 ...
7806 (overlay-put (make-overlay beginning end) 'invisible 'my-symbol)
7807
7808 ...
7809 ;; When done with the overlays:
7810 (remove-from-invisibility-spec '(my-symbol . t))
7811 ;; Or respectively:
7812 (remove-from-invisibility-spec 'my-symbol)
7813
7814 ** Changes in syntax parsing.
7815
7816 *** The syntax-directed buffer-scan functions (such as
7817 `parse-partial-sexp', `forward-word' and similar functions) can now
7818 obey syntax information specified by text properties, if the variable
7819 `parse-sexp-lookup-properties' is non-nil.
7820
7821 If the value of `parse-sexp-lookup-properties' is nil, the behavior
7822 is as before: the syntax-table of the current buffer is always
7823 used to determine the syntax of the character at the position.
7824
7825 When `parse-sexp-lookup-properties' is non-nil, the syntax of a
7826 character in the buffer is calculated thus:
7827
7828 a) if the `syntax-table' text-property of that character
7829 is a cons, this cons becomes the syntax-type;
7830
7831 Valid values of `syntax-table' text-property are: nil, a valid
7832 syntax-table, and a valid syntax-table element, i.e.,
7833 a cons cell of the form (SYNTAX-CODE . MATCHING-CHAR).
7834
7835 b) if the character's `syntax-table' text-property
7836 is a syntax table, this syntax table is used
7837 (instead of the syntax-table of the current buffer) to
7838 determine the syntax type of the character.
7839
7840 c) otherwise the syntax-type is determined by the syntax-table
7841 of the current buffer.
7842
7843 *** The meaning of \s in regular expressions is also affected by the
7844 value of `parse-sexp-lookup-properties'. The details are the same as
7845 for the syntax-directed buffer-scan functions.
7846
7847 *** There are two new syntax-codes, `!' and `|' (numeric values 14
7848 and 15). A character with a code `!' starts a comment which is ended
7849 only by another character with the same code (unless quoted). A
7850 character with a code `|' starts a string which is ended only by
7851 another character with the same code (unless quoted).
7852
7853 These codes are mainly meant for use as values of the `syntax-table'
7854 text property.
7855
7856 *** The function `parse-partial-sexp' has new semantics for the sixth
7857 arg COMMENTSTOP. If it is `syntax-table', parse stops after the start
7858 of a comment or a string, or after end of a comment or a string.
7859
7860 *** The state-list which the return value from `parse-partial-sexp'
7861 (and can also be used as an argument) now has an optional ninth
7862 element: the character address of the start of last comment or string;
7863 nil if none. The fourth and eighth elements have special values if the
7864 string/comment is started by a "!" or "|" syntax-code.
7865
7866 *** Since new features of `parse-partial-sexp' allow a complete
7867 syntactic parsing, `font-lock' no longer supports
7868 `font-lock-comment-start-regexp'.
7869
7870 ** Changes in face features
7871
7872 *** The face functions are now unconditionally defined in Emacs, even
7873 if it does not support displaying on a device that supports faces.
7874
7875 *** The function face-documentation returns the documentation string
7876 of a face (or nil if it doesn't have one).
7877
7878 *** The function face-bold-p returns t if a face should be bold.
7879 set-face-bold-p sets that flag.
7880
7881 *** The function face-italic-p returns t if a face should be italic.
7882 set-face-italic-p sets that flag.
7883
7884 *** You can now specify foreground and background colors for text
7885 by adding elements of the form (foreground-color . COLOR-NAME)
7886 and (background-color . COLOR-NAME) to the list of faces in
7887 the `face' property (either the character's text property or an
7888 overlay property).
7889
7890 This means that you no longer need to create named faces to use
7891 arbitrary colors in a Lisp package.
7892
7893 ** Changes in file-handling functions
7894
7895 *** File-access primitive functions no longer discard an extra redundant
7896 directory name from the beginning of the file name. In other words,
7897 they no longer do anything special with // or /~. That conversion
7898 is now done only in substitute-in-file-name.
7899
7900 This makes it possible for a Lisp program to open a file whose name
7901 begins with ~.
7902
7903 *** If copy-file is unable to set the date of the output file,
7904 it now signals an error with the condition file-date-error.
7905
7906 *** The inode number returned by file-attributes may be an integer (if
7907 the number fits in a Lisp integer) or a list of integers.
7908
7909 *** insert-file-contents can now read from a special file,
7910 as long as the arguments VISIT and REPLACE are nil.
7911
7912 *** The RAWFILE arg to find-file-noselect, if non-nil, now suppresses
7913 character code conversion as well as other things.
7914
7915 Meanwhile, this feature does work with remote file names
7916 (formerly it did not).
7917
7918 *** Lisp packages which create temporary files should use the TMPDIR
7919 environment variable to decide which directory to put them in.
7920
7921 *** interpreter-mode-alist elements now specify regexps
7922 instead of constant strings.
7923
7924 *** expand-file-name no longer treats `//' or `/~' specially. It used
7925 to delete all the text of a file name up through the first slash of
7926 any `//' or `/~' sequence. Now it passes them straight through.
7927
7928 substitute-in-file-name continues to treat those sequences specially,
7929 in the same way as before.
7930
7931 *** The variable `format-alist' is more general now.
7932 The FROM-FN and TO-FN in a format definition can now be strings
7933 which specify shell commands to use as filters to perform conversion.
7934
7935 *** The new function access-file tries to open a file, and signals an
7936 error if that fails. If the open succeeds, access-file does nothing
7937 else, and returns nil.
7938
7939 *** The function insert-directory now signals an error if the specified
7940 directory cannot be listed.
7941
7942 ** Changes in minibuffer input
7943
7944 *** The functions read-buffer, read-variable, read-command, read-string
7945 read-file-name, read-from-minibuffer and completing-read now take an
7946 additional argument which specifies the default value. If this
7947 argument is non-nil, it should be a string; that string is used in two
7948 ways:
7949
7950 It is returned if the user enters empty input.
7951 It is available through the history command M-n.
7952
7953 *** The functions read-string, read-from-minibuffer,
7954 read-no-blanks-input and completing-read now take an additional
7955 argument INHERIT-INPUT-METHOD. If this is non-nil, then the
7956 minibuffer inherits the current input method and the setting of
7957 enable-multibyte-characters from the previously current buffer.
7958
7959 In an interactive spec, you can use M instead of s to read an
7960 argument in this way.
7961
7962 *** All minibuffer input functions discard text properties
7963 from the text you enter in the minibuffer, unless the variable
7964 minibuffer-allow-text-properties is non-nil.
7965
7966 ** Echo area features
7967
7968 *** Clearing the echo area now runs the normal hook
7969 echo-area-clear-hook. Note that the echo area can be used while the
7970 minibuffer is active; in that case, the minibuffer is still active
7971 after the echo area is cleared.
7972
7973 *** The function current-message returns the message currently displayed
7974 in the echo area, or nil if there is none.
7975
7976 ** Keyboard input features
7977
7978 *** tty-erase-char is a new variable that reports which character was
7979 set up as the terminal's erase character when time Emacs was started.
7980
7981 *** num-nonmacro-input-events is the total number of input events
7982 received so far from the terminal. It does not count those generated
7983 by keyboard macros.
7984
7985 ** Frame-related changes
7986
7987 *** make-frame runs the normal hook before-make-frame-hook just before
7988 creating a frame, and just after creating a frame it runs the abnormal
7989 hook after-make-frame-functions with the new frame as arg.
7990
7991 *** The new hook window-configuration-change-hook is now run every time
7992 the window configuration has changed. The frame whose configuration
7993 has changed is the selected frame when the hook is run.
7994
7995 *** Each frame now independently records the order for recently
7996 selected buffers, in its buffer-list frame parameter, so that the
7997 value of other-buffer is now based on the buffers recently displayed
7998 in the selected frame.
7999
8000 *** The value of the frame parameter vertical-scroll-bars
8001 is now `left', `right' or nil. A non-nil value specifies
8002 which side of the window to put the scroll bars on.
8003
8004 ** X Windows features
8005
8006 *** You can examine X resources for other applications by binding
8007 x-resource-class around a call to x-get-resource. The usual value of
8008 x-resource-class is "Emacs", which is the correct value for Emacs.
8009
8010 *** In menus, checkboxes and radio buttons now actually work.
8011 The menu displays the current status of the box or button.
8012
8013 *** The function x-list-fonts now takes an optional fourth argument
8014 MAXIMUM which sets a limit on how many matching fonts to return.
8015 A smaller value of MAXIMUM makes the function faster.
8016
8017 If the only question is whether *any* font matches the pattern,
8018 it is good to supply 1 for this argument.
8019
8020 ** Subprocess features
8021
8022 *** A reminder: it is no longer necessary for subprocess filter
8023 functions and sentinels to do save-match-data, because Emacs does this
8024 automatically.
8025
8026 *** The new function shell-command-to-string executes a shell command
8027 and returns the output from the command as a string.
8028
8029 *** The new function process-contact returns t for a child process,
8030 and (HOSTNAME SERVICE) for a net connection.
8031
8032 ** An error in running pre-command-hook or post-command-hook
8033 does clear the variable to nil. The documentation was wrong before.
8034
8035 ** In define-key-after, if AFTER is t, the new binding now always goes
8036 at the end of the keymap. If the keymap is a menu, this means it
8037 goes after the other menu items.
8038
8039 ** If you have a program that makes several changes in the same area
8040 of the buffer, you can use the macro combine-after-change-calls
8041 around that Lisp code to make it faster when after-change hooks
8042 are in use.
8043
8044 The macro arranges to call the after-change functions just once for a
8045 series of several changes--if that seems safe.
8046
8047 Don't alter the variables after-change-functions and
8048 after-change-function within the body of a combine-after-change-calls
8049 form.
8050
8051 ** If you define an abbrev (with define-abbrev) whose EXPANSION
8052 is not a string, then the abbrev does not expand in the usual sense,
8053 but its hook is still run.
8054
8055 ** Normally, the Lisp debugger is not used (even if you have enabled it)
8056 for errors that are handled by condition-case.
8057
8058 If you set debug-on-signal to a non-nil value, then the debugger is called
8059 regardless of whether there is a handler for the condition. This is
8060 useful for debugging problems that happen inside of a condition-case.
8061
8062 This mode of operation seems to be unreliable in other ways. Errors that
8063 are normal and ought to be handled, perhaps in timers or process
8064 filters, will instead invoke the debugger. So don't say you weren't
8065 warned.
8066
8067 ** The new variable ring-bell-function lets you specify your own
8068 way for Emacs to "ring the bell".
8069
8070 ** If run-at-time's TIME argument is t, the action is repeated at
8071 integral multiples of REPEAT from the epoch; this is useful for
8072 functions like display-time.
8073
8074 ** You can use the function locate-library to find the precise file
8075 name of a Lisp library. This isn't new, but wasn't documented before.
8076
8077 ** Commands for entering view mode have new optional arguments that
8078 can be used from Lisp. Low-level entrance to and exit from view mode
8079 is done by functions view-mode-enter and view-mode-exit.
8080
8081 ** batch-byte-compile-file now makes Emacs return a nonzero status code
8082 if there is an error in compilation.
8083
8084 ** pop-to-buffer, switch-to-buffer-other-window and
8085 switch-to-buffer-other-frame now accept an additional optional
8086 argument NORECORD, much like switch-to-buffer. If it is non-nil,
8087 they don't put the buffer at the front of the buffer list.
8088
8089 ** If your .emacs file leaves the *scratch* buffer non-empty,
8090 Emacs does not display the startup message, so as to avoid changing
8091 the *scratch* buffer.
8092
8093 ** The new function regexp-opt returns an efficient regexp to match a string.
8094 The arguments are STRINGS and (optionally) PAREN. This function can be used
8095 where regexp matching or searching is intensively used and speed is important,
8096 e.g., in Font Lock mode.
8097
8098 ** The variable buffer-display-count is local to each buffer,
8099 and is incremented each time the buffer is displayed in a window.
8100 It starts at 0 when the buffer is created.
8101
8102 ** The new function compose-mail starts composing a mail message
8103 using the user's chosen mail composition agent (specified with the
8104 variable mail-user-agent). It has variants compose-mail-other-window
8105 and compose-mail-other-frame.
8106
8107 ** The `user-full-name' function now takes an optional parameter which
8108 can either be a number (the UID) or a string (the login name). The
8109 full name of the specified user will be returned.
8110
8111 ** Lisp packages that load files of customizations, or any other sort
8112 of user profile, should obey the variable init-file-user in deciding
8113 where to find it. They should load the profile of the user name found
8114 in that variable. If init-file-user is nil, meaning that the -q
8115 option was used, then Lisp packages should not load the customization
8116 files at all.
8117
8118 ** format-time-string now allows you to specify the field width
8119 and type of padding. This works as in printf: you write the field
8120 width as digits in the middle of a %-construct. If you start
8121 the field width with 0, it means to pad with zeros.
8122
8123 For example, %S normally specifies the number of seconds since the
8124 minute; %03S means to pad this with zeros to 3 positions, %_3S to pad
8125 with spaces to 3 positions. Plain %3S pads with zeros, because that
8126 is how %S normally pads to two positions.
8127
8128 ** thing-at-point now supports a new kind of "thing": url.
8129
8130 ** imenu.el changes.
8131
8132 You can now specify a function to be run when selecting an
8133 item from menu created by imenu.
8134
8135 An example of using this feature: if we define imenu items for the
8136 #include directives in a C file, we can open the included file when we
8137 select one of those items.
8138 \f
8139 * Emacs 19.34 is a bug-fix release with no user-visible changes.
8140 \f
8141 * Changes in Emacs 19.33.
8142
8143 ** Bibtex mode no longer turns on Auto Fill automatically. (No major
8144 mode should do that--it is the user's choice.)
8145
8146 ** The variable normal-auto-fill-function specifies the function to
8147 use for auto-fill-function, if and when Auto Fill is turned on.
8148 Major modes can set this locally to alter how Auto Fill works.
8149 \f
8150 * Editing Changes in Emacs 19.32
8151
8152 ** C-x f with no argument now signals an error.
8153 To set the fill column at the current column, use C-u C-x f.
8154
8155 ** Expanding dynamic abbrevs with M-/ is now smarter about case
8156 conversion. If you type the abbreviation with mixed case, and it
8157 matches the beginning of the expansion including case, then the
8158 expansion is copied verbatim. Using SPC M-/ to copy an additional
8159 word always copies it verbatim except when the previous copied word is
8160 all caps.
8161
8162 ** On a non-windowing terminal, which can display only one Emacs frame
8163 at a time, creating a new frame with C-x 5 2 also selects that frame.
8164
8165 When using a display that can show multiple frames at once, C-x 5 2
8166 does make the frame visible, but does not select it. This is the same
8167 as in previous Emacs versions.
8168
8169 ** You can use C-x 5 2 to create multiple frames on MSDOS, just as on a
8170 non-X terminal on Unix. Of course, only one frame is visible at any
8171 time, since your terminal doesn't have the ability to display multiple
8172 frames.
8173
8174 ** On Windows, set win32-pass-alt-to-system to a non-nil value
8175 if you would like tapping the Alt key to invoke the Windows menu.
8176 This feature is not enabled by default; since the Alt key is also the
8177 Meta key, it is too easy and painful to activate this feature by
8178 accident.
8179
8180 ** The command apply-macro-to-region-lines repeats the last defined
8181 keyboard macro once for each complete line within the current region.
8182 It does this line by line, by moving point to the beginning of that
8183 line and then executing the macro.
8184
8185 This command is not new, but was never documented before.
8186
8187 ** You can now use Mouse-1 to place the region around a string constant
8188 (something surrounded by doublequote characters or other delimiter
8189 characters of like syntax) by double-clicking on one of the delimiting
8190 characters.
8191
8192 ** Font Lock mode
8193
8194 *** Font Lock support modes
8195
8196 Font Lock can be configured to use Fast Lock mode and Lazy Lock mode (see
8197 below) in a flexible way. Rather than adding the appropriate function to the
8198 hook font-lock-mode-hook, you can use the new variable font-lock-support-mode
8199 to control which modes have Fast Lock mode or Lazy Lock mode turned on when
8200 Font Lock mode is enabled.
8201
8202 For example, to use Fast Lock mode when Font Lock mode is turned on, put:
8203
8204 (setq font-lock-support-mode 'fast-lock-mode)
8205
8206 in your ~/.emacs.
8207
8208 *** lazy-lock
8209
8210 The lazy-lock package speeds up Font Lock mode by making fontification occur
8211 only when necessary, such as when a previously unfontified part of the buffer
8212 becomes visible in a window. When you create a buffer with Font Lock mode and
8213 Lazy Lock mode turned on, the buffer is not fontified. When certain events
8214 occur (such as scrolling), Lazy Lock makes sure that the visible parts of the
8215 buffer are fontified. Lazy Lock also defers on-the-fly fontification until
8216 Emacs has been idle for a given amount of time.
8217
8218 To use this package, put in your ~/.emacs:
8219
8220 (setq font-lock-support-mode 'lazy-lock-mode)
8221
8222 To control the package behaviour, see the documentation for `lazy-lock-mode'.
8223
8224 ** Changes in BibTeX mode.
8225
8226 *** For all entries allow spaces and tabs between opening brace or
8227 paren and key.
8228
8229 *** Non-escaped double-quoted characters (as in `Sch"of') are now
8230 supported.
8231
8232 ** Gnus changes.
8233
8234 Gnus, the Emacs news reader, has undergone further rewriting. Many new
8235 commands and variables have been added. There should be no
8236 significant incompatibilities between this Gnus version and the
8237 previously released version, except in the message composition area.
8238
8239 Below is a list of the more user-visible changes. Coding changes
8240 between Gnus 5.1 and 5.2 are more extensive.
8241
8242 *** A new message composition mode is used. All old customization
8243 variables for mail-mode, rnews-reply-mode and gnus-msg are now
8244 obsolete.
8245
8246 *** Gnus is now able to generate "sparse" threads -- threads where
8247 missing articles are represented by empty nodes.
8248
8249 (setq gnus-build-sparse-threads 'some)
8250
8251 *** Outgoing articles are stored on a special archive server.
8252
8253 To disable this: (setq gnus-message-archive-group nil)
8254
8255 *** Partial thread regeneration now happens when articles are
8256 referred.
8257
8258 *** Gnus can make use of GroupLens predictions:
8259
8260 (setq gnus-use-grouplens t)
8261
8262 *** A trn-line tree buffer can be displayed.
8263
8264 (setq gnus-use-trees t)
8265
8266 *** An nn-like pick-and-read minor mode is available for the summary
8267 buffers.
8268
8269 (add-hook 'gnus-summary-mode-hook 'gnus-pick-mode)
8270
8271 *** In binary groups you can use a special binary minor mode:
8272
8273 `M-x gnus-binary-mode'
8274
8275 *** Groups can be grouped in a folding topic hierarchy.
8276
8277 (add-hook 'gnus-group-mode-hook 'gnus-topic-mode)
8278
8279 *** Gnus can re-send and bounce mail.
8280
8281 Use the `S D r' and `S D b'.
8282
8283 *** Groups can now have a score, and bubbling based on entry frequency
8284 is possible.
8285
8286 (add-hook 'gnus-summary-exit-hook 'gnus-summary-bubble-group)
8287
8288 *** Groups can be process-marked, and commands can be performed on
8289 groups of groups.
8290
8291 *** Caching is possible in virtual groups.
8292
8293 *** nndoc now understands all kinds of digests, mail boxes, rnews news
8294 batches, ClariNet briefs collections, and just about everything else.
8295
8296 *** Gnus has a new backend (nnsoup) to create/read SOUP packets.
8297
8298 *** The Gnus cache is much faster.
8299
8300 *** Groups can be sorted according to many criteria.
8301
8302 For instance: (setq gnus-group-sort-function 'gnus-group-sort-by-rank)
8303
8304 *** New group parameters have been introduced to set list-address and
8305 expiration times.
8306
8307 *** All formatting specs allow specifying faces to be used.
8308
8309 *** There are several more commands for setting/removing/acting on
8310 process marked articles on the `M P' submap.
8311
8312 *** The summary buffer can be limited to show parts of the available
8313 articles based on a wide range of criteria. These commands have been
8314 bound to keys on the `/' submap.
8315
8316 *** Articles can be made persistent -- as an alternative to saving
8317 articles with the `*' command.
8318
8319 *** All functions for hiding article elements are now toggles.
8320
8321 *** Article headers can be buttonized.
8322
8323 (add-hook 'gnus-article-display-hook 'gnus-article-add-buttons-to-head)
8324
8325 *** All mail backends support fetching articles by Message-ID.
8326
8327 *** Duplicate mail can now be treated properly. See the
8328 `nnmail-treat-duplicates' variable.
8329
8330 *** All summary mode commands are available directly from the article
8331 buffer.
8332
8333 *** Frames can be part of `gnus-buffer-configuration'.
8334
8335 *** Mail can be re-scanned by a daemonic process.
8336
8337 *** Gnus can make use of NoCeM files to filter spam.
8338
8339 (setq gnus-use-nocem t)
8340
8341 *** Groups can be made permanently visible.
8342
8343 (setq gnus-permanently-visible-groups "^nnml:")
8344
8345 *** Many new hooks have been introduced to make customizing easier.
8346
8347 *** Gnus respects the Mail-Copies-To header.
8348
8349 *** Threads can be gathered by looking at the References header.
8350
8351 (setq gnus-summary-thread-gathering-function
8352 'gnus-gather-threads-by-references)
8353
8354 *** Read articles can be stored in a special backlog buffer to avoid
8355 refetching.
8356
8357 (setq gnus-keep-backlog 50)
8358
8359 *** A clean copy of the current article is always stored in a separate
8360 buffer to allow easier treatment.
8361
8362 *** Gnus can suggest where to save articles. See `gnus-split-methods'.
8363
8364 *** Gnus doesn't have to do as much prompting when saving.
8365
8366 (setq gnus-prompt-before-saving t)
8367
8368 *** gnus-uu can view decoded files asynchronously while fetching
8369 articles.
8370
8371 (setq gnus-uu-grabbed-file-functions 'gnus-uu-grab-view)
8372
8373 *** Filling in the article buffer now works properly on cited text.
8374
8375 *** Hiding cited text adds buttons to toggle hiding, and how much
8376 cited text to hide is now customizable.
8377
8378 (setq gnus-cited-lines-visible 2)
8379
8380 *** Boring headers can be hidden.
8381
8382 (add-hook 'gnus-article-display-hook 'gnus-article-hide-boring-headers)
8383
8384 *** Default scoring values can now be set from the menu bar.
8385
8386 *** Further syntax checking of outgoing articles have been added.
8387
8388 The Gnus manual has been expanded. It explains all these new features
8389 in greater detail.
8390 \f
8391 * Lisp Changes in Emacs 19.32
8392
8393 ** The function set-visited-file-name now accepts an optional
8394 second argument NO-QUERY. If it is non-nil, then the user is not
8395 asked for confirmation in the case where the specified file already
8396 exists.
8397
8398 ** The variable print-length applies to printing vectors and bitvectors,
8399 as well as lists.
8400
8401 ** The new function keymap-parent returns the parent keymap
8402 of a given keymap.
8403
8404 ** The new function set-keymap-parent specifies a new parent for a
8405 given keymap. The arguments are KEYMAP and PARENT. PARENT must be a
8406 keymap or nil.
8407
8408 ** Sometimes menu keymaps use a command name, a symbol, which is really
8409 an automatically generated alias for some other command, the "real"
8410 name. In such a case, you should give that alias symbol a non-nil
8411 menu-alias property. That property tells the menu system to look for
8412 equivalent keys for the real name instead of equivalent keys for the
8413 alias.
8414 \f
8415 * Editing Changes in Emacs 19.31
8416
8417 ** Freedom of the press restricted in the United States.
8418
8419 Emacs has been censored in accord with the Communications Decency Act.
8420 This includes removing some features of the doctor program. That law
8421 was described by its supporters as a ban on pornography, but it bans
8422 far more than that. The Emacs distribution has never contained any
8423 pornography, but parts of it were nonetheless prohibited.
8424
8425 For information on US government censorship of the Internet, and what
8426 you can do to bring back freedom of the press, see the web site
8427 `http://www.vtw.org/'.
8428
8429 ** A note about C mode indentation customization.
8430
8431 The old (Emacs 19.29) ways of specifying a C indentation style
8432 do not normally work in the new implementation of C mode.
8433 It has its own methods of customizing indentation, which are
8434 much more powerful than the old C mode. See the Editing Programs
8435 chapter of the manual for details.
8436
8437 However, you can load the library cc-compat to make the old
8438 customization variables take effect.
8439
8440 ** Marking with the mouse.
8441
8442 When you mark a region with the mouse, the region now remains
8443 highlighted until the next input event, regardless of whether you are
8444 using M-x transient-mark-mode.
8445
8446 ** Improved Windows NT/95 support.
8447
8448 *** Emacs now supports scroll bars on Windows NT and Windows 95.
8449
8450 *** Emacs now supports subprocesses on Windows 95. (Subprocesses used
8451 to work on NT only and not on 95.)
8452
8453 *** There are difficulties with subprocesses, though, due to problems
8454 in Windows, beyond the control of Emacs. They work fine as long as
8455 you run Windows applications. The problems arise when you run a DOS
8456 application in a subprocesses. Since current shells run as DOS
8457 applications, these problems are significant.
8458
8459 If you run a DOS application in a subprocess, then the application is
8460 likely to busy-wait, which means that your machine will be 100% busy.
8461 However, if you don't mind the temporary heavy load, the subprocess
8462 will work OK as long as you tell it to terminate before you start any
8463 other DOS application as a subprocess.
8464
8465 Emacs is unable to terminate or interrupt a DOS subprocess.
8466 You have to do this by providing input directly to the subprocess.
8467
8468 If you run two DOS applications at the same time in two separate
8469 subprocesses, even if one of them is asynchronous, you will probably
8470 have to reboot your machine--until then, it will remain 100% busy.
8471 Windows simply does not cope when one Windows process tries to run two
8472 separate DOS subprocesses. Typing CTL-ALT-DEL and then choosing
8473 Shutdown seems to work although it may take a few minutes.
8474
8475 ** M-x resize-minibuffer-mode.
8476
8477 This command, not previously mentioned in NEWS, toggles a mode in
8478 which the minibuffer window expands to show as many lines as the
8479 minibuffer contains.
8480
8481 ** `title' frame parameter and resource.
8482
8483 The `title' X resource now specifies just the frame title, nothing else.
8484 It does not affect the name used for looking up other X resources.
8485 It works by setting the new `title' frame parameter, which likewise
8486 affects just the displayed title of the frame.
8487
8488 The `name' parameter continues to do what it used to do:
8489 it specifies the frame name for looking up X resources,
8490 and also serves as the default for the displayed title
8491 when the `title' parameter is unspecified or nil.
8492
8493 ** Emacs now uses the X toolkit by default, if you have a new
8494 enough version of X installed (X11R5 or newer).
8495
8496 ** When you compile Emacs with the Motif widget set, Motif handles the
8497 F10 key by activating the menu bar. To avoid confusion, the usual
8498 Emacs binding of F10 is replaced with a no-op when using Motif.
8499
8500 If you want to be able to use F10 in Emacs, you can rebind the Motif
8501 menubar to some other key which you don't use. To do so, add
8502 something like this to your X resources file. This example rebinds
8503 the Motif menu bar activation key to S-F12:
8504
8505 Emacs*defaultVirtualBindings: osfMenuBar : Shift<Key>F12
8506
8507 ** In overwrite mode, DEL now inserts spaces in most cases
8508 to replace the characters it "deletes".
8509
8510 ** The Rmail summary now shows the number of lines in each message.
8511
8512 ** Rmail has a new command M-x unforward-rmail-message, which extracts
8513 a forwarded message from the message that forwarded it. To use it,
8514 select a message which contains a forwarded message and then type the command.
8515 It inserts the forwarded message as a separate Rmail message
8516 immediately after the selected one.
8517
8518 This command also undoes the textual modifications that are standardly
8519 made, as part of forwarding, by Rmail and other mail reader programs.
8520
8521 ** Turning off saving of .saves-... files in your home directory.
8522
8523 Each Emacs session writes a file named .saves-... in your home
8524 directory to record which files M-x recover-session should recover.
8525 If you exit Emacs normally with C-x C-c, it deletes that file. If
8526 Emacs or the operating system crashes, the file remains for M-x
8527 recover-session.
8528
8529 You can turn off the writing of these files by setting
8530 auto-save-list-file-name to nil. If you do this, M-x recover-session
8531 will not work.
8532
8533 Some previous Emacs versions failed to delete these files even on
8534 normal exit. This is fixed now. If you are thinking of turning off
8535 this feature because of past experiences with versions that had this
8536 bug, it would make sense to check whether you still want to do so
8537 now that the bug is fixed.
8538
8539 ** Changes to Version Control (VC)
8540
8541 There is a new variable, vc-follow-symlinks. It indicates what to do
8542 when you visit a link to a file that is under version control.
8543 Editing the file through the link bypasses the version control system,
8544 which is dangerous and probably not what you want.
8545
8546 If this variable is t, VC follows the link and visits the real file,
8547 telling you about it in the echo area. If it is `ask' (the default),
8548 VC asks for confirmation whether it should follow the link. If nil,
8549 the link is visited and a warning displayed.
8550
8551 ** iso-acc.el now lets you specify a choice of language.
8552 Languages include "latin-1" (the default) and "latin-2" (which
8553 is designed for entering ISO Latin-2 characters).
8554
8555 There are also choices for specific human languages such as French and
8556 Portuguese. These are subsets of Latin-1, which differ in that they
8557 enable only the accent characters needed for particular language.
8558 The other accent characters, not needed for the chosen language,
8559 remain normal.
8560
8561 ** Posting articles and sending mail now has M-TAB completion on various
8562 header fields (Newsgroups, To, CC, ...).
8563
8564 Completion in the Newsgroups header depends on the list of groups
8565 known to your news reader. Completion in the Followup-To header
8566 offers those groups which are in the Newsgroups header, since
8567 Followup-To usually just holds one of those.
8568
8569 Completion in fields that hold mail addresses works based on the list
8570 of local users plus your aliases. Additionally, if your site provides
8571 a mail directory or a specific host to use for any unrecognized user
8572 name, you can arrange to query that host for completion also. (See the
8573 documentation of variables `mail-directory-process' and
8574 `mail-directory-stream'.)
8575
8576 ** A greatly extended sgml-mode offers new features such as (to be configured)
8577 skeletons with completing read for tags and attributes, typing named
8578 characters including optionally all 8bit characters, making tags invisible
8579 with optional alternate display text, skipping and deleting tag(pair)s.
8580
8581 Note: since Emacs' syntax feature cannot limit the special meaning of ', " and
8582 - to inside <>, for some texts the result, especially of font locking, may be
8583 wrong (see `sgml-specials' if you get wrong results).
8584
8585 The derived html-mode configures this with tags and attributes more or
8586 less HTML3ish. It also offers optional quick keys like C-c 1 for
8587 headline or C-c u for unordered list (see `html-quick-keys'). Edit /
8588 Text Properties / Face or M-g combinations create tags as applicable.
8589 Outline minor mode is supported and level 1 font-locking tries to
8590 fontify tag contents (which only works when they fit on one line, due
8591 to a limitation in font-lock).
8592
8593 External viewing via browse-url can occur automatically upon saving.
8594
8595 ** M-x imenu-add-to-menubar now adds to the menu bar for the current
8596 buffer only. If you want to put an Imenu item in the menu bar for all
8597 buffers that use a particular major mode, use the mode hook, as in
8598 this example:
8599
8600 (add-hook 'emacs-lisp-mode-hook
8601 '(lambda () (imenu-add-to-menubar "Index")))
8602
8603 ** Changes in BibTeX mode.
8604
8605 *** Field names may now contain digits, hyphens, and underscores.
8606
8607 *** Font Lock mode is now supported.
8608
8609 *** bibtex-make-optional-field is no longer interactive.
8610
8611 *** If bibtex-maintain-sorted-entries is non-nil, inserting new
8612 entries is now done with a faster algorithm. However, inserting
8613 will fail in this case if the buffer contains invalid entries or
8614 isn't in sorted order, so you should finish each entry with C-c C-c
8615 (bibtex-close-entry) after you have inserted or modified it.
8616 The default value of bibtex-maintain-sorted-entries is nil.
8617
8618 *** Function `show-all' is no longer bound to a key, since C-u C-c C-q
8619 does the same job.
8620
8621 *** Entries with quotes inside quote-delimited fields (as `author =
8622 "Stefan Sch{\"o}f"') are now supported.
8623
8624 *** Case in field names doesn't matter anymore when searching for help
8625 text.
8626
8627 ** Font Lock mode
8628
8629 *** Global Font Lock mode
8630
8631 Font Lock mode can be turned on globally, in buffers that support it, by the
8632 new command global-font-lock-mode. You can use the new variable
8633 font-lock-global-modes to control which modes have Font Lock mode automagically
8634 turned on. By default, this variable is set so that Font Lock mode is turned
8635 on globally where the buffer mode supports it.
8636
8637 For example, to automagically turn on Font Lock mode where supported, put:
8638
8639 (global-font-lock-mode t)
8640
8641 in your ~/.emacs.
8642
8643 *** Local Refontification
8644
8645 In Font Lock mode, editing a line automatically refontifies that line only.
8646 However, if your change alters the syntactic context for following lines,
8647 those lines remain incorrectly fontified. To refontify them, use the new
8648 command M-g M-g (font-lock-fontify-block).
8649
8650 In certain major modes, M-g M-g refontifies the entire current function.
8651 (The variable font-lock-mark-block-function controls how to find the
8652 current function.) In other major modes, M-g M-g refontifies 16 lines
8653 above and below point.
8654
8655 With a prefix argument N, M-g M-g refontifies N lines above and below point.
8656
8657 ** Follow mode
8658
8659 Follow mode is a new minor mode combining windows showing the same
8660 buffer into one tall "virtual window". The windows are typically two
8661 side-by-side windows. Follow mode makes them scroll together as if
8662 they were a unit. To use it, go to a frame with just one window,
8663 split it into two side-by-side windows using C-x 3, and then type M-x
8664 follow-mode.
8665
8666 M-x follow-mode turns off Follow mode if it is already enabled.
8667
8668 To display two side-by-side windows and activate Follow mode, use the
8669 command M-x follow-delete-other-windows-and-split.
8670
8671 ** hide-show changes.
8672
8673 The hooks hs-hide-hooks and hs-show-hooks have been renamed
8674 to hs-hide-hook and hs-show-hook, to follow the convention for
8675 normal hooks.
8676
8677 ** Simula mode now has a menu containing the most important commands.
8678 The new command simula-indent-exp is bound to C-M-q.
8679
8680 ** etags can now handle programs written in Erlang. Files are
8681 recognised by the extensions .erl and .hrl. The tagged lines are
8682 those that begin a function, record, or macro.
8683
8684 ** MSDOS Changes
8685
8686 *** It is now possible to compile Emacs with the version 2 of DJGPP.
8687 Compilation with DJGPP version 1 also still works.
8688
8689 *** The documentation of DOS-specific aspects of Emacs was rewritten
8690 and expanded; see the ``MS-DOS'' node in the on-line docs.
8691
8692 *** Emacs now uses ~ for backup file names, not .bak.
8693
8694 *** You can simulate mouse-3 on two-button mice by simultaneously
8695 pressing both mouse buttons.
8696
8697 *** A number of packages and commands which previously failed or had
8698 restricted functionality on MS-DOS, now work. The most important ones
8699 are:
8700
8701 **** Printing (both with `M-x lpr-buffer' and with `ps-print' package)
8702 now works.
8703
8704 **** `Ediff' works (in a single-frame mode).
8705
8706 **** `M-x display-time' can be used on MS-DOS (due to the new
8707 implementation of Emacs timers, see below).
8708
8709 **** `Dired' supports Unix-style shell wildcards.
8710
8711 **** The `c-macro-expand' command now works as on other platforms.
8712
8713 **** `M-x recover-session' works.
8714
8715 **** `M-x list-colors-display' displays all the available colors.
8716
8717 **** The `TPU-EDT' package works.
8718 \f
8719 * Lisp changes in Emacs 19.31.
8720
8721 ** The function using-unix-filesystems on Windows NT and Windows 95
8722 tells Emacs to read and write files assuming that they reside on a
8723 remote Unix filesystem. No CR/LF translation is done on any files in
8724 this case. Invoking using-unix-filesystems with t activates this
8725 behavior, and invoking it with any other value deactivates it.
8726
8727 ** Change in system-type and system-configuration values.
8728
8729 The value of system-type on a Linux-based GNU system is now `lignux',
8730 not `linux'. This means that some programs which use `system-type'
8731 need to be changed. The value of `system-configuration' will also
8732 be different.
8733
8734 It is generally recommended to use `system-configuration' rather
8735 than `system-type'.
8736
8737 See the file LINUX-GNU in this directory for more about this.
8738
8739 ** The functions shell-command and dired-call-process
8740 now run file name handlers for default-directory, if it has them.
8741
8742 ** Undoing the deletion of text now restores the positions of markers
8743 that pointed into or next to the deleted text.
8744
8745 ** Timers created with run-at-time now work internally to Emacs, and
8746 no longer use a separate process. Therefore, they now work more
8747 reliably and can be used for shorter time delays.
8748
8749 The new function run-with-timer is a convenient way to set up a timer
8750 to run a specified amount of time after the present. A call looks
8751 like this:
8752
8753 (run-with-timer SECS REPEAT FUNCTION ARGS...)
8754
8755 SECS says how many seconds should elapse before the timer happens.
8756 It may be an integer or a floating point number. When the timer
8757 becomes ripe, the action is to call FUNCTION with arguments ARGS.
8758
8759 REPEAT gives the interval for repeating the timer (measured in
8760 seconds). It may be an integer or a floating point number. nil or 0
8761 means don't repeat at all--call FUNCTION just once.
8762
8763 *** with-timeout provides an easy way to do something but give
8764 up if too much time passes.
8765
8766 (with-timeout (SECONDS TIMEOUT-FORMS...) BODY...)
8767
8768 This executes BODY, but gives up after SECONDS seconds.
8769 If it gives up, it runs the TIMEOUT-FORMS and returns the value
8770 of the last one of them. Normally it returns the value of the last
8771 form in BODY.
8772
8773 *** You can now arrange to call a function whenever Emacs is idle for
8774 a certain length of time. To do this, call run-with-idle-timer. A
8775 call looks like this:
8776
8777 (run-with-idle-timer SECS REPEAT FUNCTION ARGS...)
8778
8779 SECS says how many seconds of idleness should elapse before the timer
8780 runs. It may be an integer or a floating point number. When the
8781 timer becomes ripe, the action is to call FUNCTION with arguments
8782 ARGS.
8783
8784 Emacs becomes idle whenever it finishes executing a keyboard or mouse
8785 command. It remains idle until it receives another keyboard or mouse
8786 command.
8787
8788 REPEAT, if non-nil, means this timer should be activated again each
8789 time Emacs becomes idle and remains idle for SECS seconds The timer
8790 does not repeat if Emacs *remains* idle; it runs at most once after
8791 each time Emacs becomes idle.
8792
8793 If REPEAT is nil, the timer runs just once, the first time Emacs is
8794 idle for SECS seconds.
8795
8796 *** post-command-idle-hook is now obsolete; you shouldn't use it at
8797 all, because it interferes with the idle timer mechanism. If your
8798 programs use post-command-idle-hook, convert them to use idle timers
8799 instead.
8800
8801 *** y-or-n-p-with-timeout lets you ask a question but give up if
8802 there is no answer within a certain time.
8803
8804 (y-or-n-p-with-timeout PROMPT SECONDS DEFAULT-VALUE)
8805
8806 asks the question PROMPT (just like y-or-n-p). If the user answers
8807 within SECONDS seconds, it returns the answer that the user gave.
8808 Otherwise it gives up after SECONDS seconds, and returns DEFAULT-VALUE.
8809
8810 ** Minor change to `encode-time': you can now pass more than seven
8811 arguments. If you do that, the first six arguments have the usual
8812 meaning, the last argument is interpreted as the time zone, and the
8813 arguments in between are ignored.
8814
8815 This means that it works to use the list returned by `decode-time' as
8816 the list of arguments for `encode-time'.
8817
8818 ** The default value of load-path now includes the directory
8819 /usr/local/share/emacs/VERSION/site-lisp In addition to
8820 /usr/local/share/emacs/site-lisp. You can use this new directory for
8821 site-specific Lisp packages that belong with a particular Emacs
8822 version.
8823
8824 It is not unusual for a Lisp package that works well in one Emacs
8825 version to cause trouble in another. Sometimes packages need updating
8826 for incompatible changes; sometimes they look at internal data that
8827 has changed; sometimes the package has been installed in Emacs itself
8828 and the installed version should be used. Whatever the reason for the
8829 problem, this new feature makes it easier to solve.
8830
8831 ** When your program contains a fixed file name (like .completions or
8832 .abbrev.defs), the file name usually needs to be different on operating
8833 systems with limited file name syntax.
8834
8835 Now you can avoid ad-hoc conditionals by using the function
8836 convert-standard-filename to convert the file name to a proper form
8837 for each operating system. Here is an example of use, from the file
8838 completions.el:
8839
8840 (defvar save-completions-file-name
8841 (convert-standard-filename "~/.completions")
8842 "*The filename to save completions to.")
8843
8844 This sets the variable save-completions-file-name to a value that
8845 depends on the operating system, because the definition of
8846 convert-standard-filename depends on the operating system. On
8847 Unix-like systems, it returns the specified file name unchanged. On
8848 MS-DOS, it adapts the name to fit the limitations of that system.
8849
8850 ** The interactive spec N now returns the numeric prefix argument
8851 rather than the raw prefix argument. (It still reads a number using the
8852 minibuffer if there is no prefix argument at all.)
8853
8854 ** When a process is deleted, this no longer disconnects the process
8855 marker from its buffer position.
8856
8857 ** The variable garbage-collection-messages now controls whether
8858 Emacs displays a message at the beginning and end of garbage collection.
8859 The default is nil, meaning there are no messages.
8860
8861 ** The variable debug-ignored-errors specifies certain kinds of errors
8862 that should not enter the debugger. Its value is a list of error
8863 condition symbols and/or regular expressions. If the error has any
8864 of the condition symbols listed, or if any of the regular expressions
8865 matches the error message, then that error does not enter the debugger,
8866 regardless of the value of debug-on-error.
8867
8868 This variable is initialized to match certain common but uninteresting
8869 errors that happen often during editing.
8870
8871 ** The new function error-message-string converts an error datum
8872 into its error message. The error datum is what condition-case
8873 puts into the variable, to describe the error that happened.
8874
8875 ** Anything that changes which buffer appears in a given window
8876 now runs the window-scroll-functions for that window.
8877
8878 ** The new function get-buffer-window-list returns a list of windows displaying
8879 a buffer. The function is called with the buffer (a buffer object or a buffer
8880 name) and two optional arguments specifying the minibuffer windows and frames
8881 to search. Therefore this function takes optional args like next-window etc.,
8882 and not get-buffer-window.
8883
8884 ** buffer-substring now runs the hook buffer-access-fontify-functions,
8885 calling each function with two arguments--the range of the buffer
8886 being accessed. buffer-substring-no-properties does not call them.
8887
8888 If you use this feature, you should set the variable
8889 buffer-access-fontified-property to a non-nil symbol, which is a
8890 property name. Then, if all the characters in the buffer range have a
8891 non-nil value for that property, the buffer-access-fontify-functions
8892 are not called. When called, these functions should put a non-nil
8893 property on the text that they fontify, so that they won't get called
8894 over and over for the same text.
8895
8896 ** Changes in lisp-mnt.el
8897
8898 *** The lisp-mnt package can now recognize file headers that are written
8899 in the formats used by the `what' command and the RCS `ident' command:
8900
8901 ;; @(#) HEADER: text
8902 ;; $HEADER: text $
8903
8904 in addition to the normal
8905
8906 ;; HEADER: text
8907
8908 *** The commands lm-verify and lm-synopsis are now interactive. lm-verify
8909 checks that the library file has proper sections and headers, and
8910 lm-synopsis extracts first line "synopsis'"information.
8911
8912
8913 \f
8914 * For older news, see the file ONEWS
8915
8916 ----------------------------------------------------------------------
8917 Copyright information:
8918
8919 Copyright (C) 1999, 2000 Free Software Foundation, Inc.
8920
8921 Permission is granted to anyone to make or distribute verbatim copies
8922 of this document as received, in any medium, provided that the
8923 copyright notice and this permission notice are preserved,
8924 thus giving the recipient permission to redistribute in turn.
8925
8926 Permission is granted to distribute modified versions
8927 of this document, or of portions of it,
8928 under the above conditions, provided also that they
8929 carry prominent notices stating who last changed them.
8930 \f
8931 Local variables:
8932 mode: outline
8933 paragraph-separate: "[ \f]*$"
8934 end: