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