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1 GNU Emacs NEWS -- history of user-visible changes. 2000-09-27
2 Copyright (C) 1999, 2000 Free Software Foundation, Inc.
3 See the end for copying conditions.
4
5 Please send Emacs bug reports to bug-gnu-emacs@gnu.org.
6 For older news, see the file ONEWS
7
8 \f
9 * Installation Changes in Emacs 21.1
10
11 ** Support for GNU/Linux on IA64 machines has been added.
12
13 ** Support for LynxOS has been added.
14
15 ** `movemail' defaults to supporting POP. You can turn this off using
16 the --without-pop configure option, should that be necessary.
17
18 ** There are new configure options associated with the support for
19 images and toolkit scrollbars. Use the --help option in `configure'
20 to list them.
21
22 ** There is a new configure option `--without-xim' that instructs
23 Emacs to not use X Input Methods (XIM), if these are available.
24
25 ** There is a new configure option `--disable-largefile' to omit
26 Unix-98-style support for large files if that is available.
27
28 ** You can build a 64-bit Emacs for SPARC/Solaris systems which
29 support 64-bit executables and also on Irix 6.5. This increases the
30 maximum buffer size. See etc/MACHINES for instructions.
31
32 \f
33 * Changes in Emacs 21.1
34
35 ** `browse-url-gnome-moz' is a new option for
36 `browse-url-browser-function', invoking Mozilla in GNOME.
37
38 +++
39 ** The new global minor mode `auto-image-file-mode' allows image files
40 to be visited as images.
41
42 +++
43 ** The functions `keep-lines', `flush-lines' and `how-many' now
44 operate on the active region in Transient Mark mode.
45
46 ** The header line in an Info buffer is now displayed as an emacs header-line
47 (which is like a mode-line, but at the top of the window), so that it
48 remains visible even when the buffer has been scrolled. This behavior
49 may be disabled by customizing the option `Info-use-header-line'.
50
51 ** `gnus-user-agent' is a new possibility for `mail-user-agent'. It
52 is like `message-user-agent', but with all the Gnus paraphernalia.
53
54 +++
55 ** The recommended way of using Iswitchb is via the new global minor
56 mode `iswitchb-mode'.
57
58 ** Gnus changes.
59
60 The Gnus NEWS entries are short, but they reflect sweeping changes in
61 four areas: Article display treatment, MIME treatment,
62 internationalization and mail-fetching.
63
64 *** The mail-fetching functions have changed. See the manual for the
65 many details. In particular, all procmail fetching variables are gone.
66
67 If you used procmail like in
68
69 (setq nnmail-use-procmail t)
70 (setq nnmail-spool-file 'procmail)
71 (setq nnmail-procmail-directory "~/mail/incoming/")
72 (setq nnmail-procmail-suffix "\\.in")
73
74 this now has changed to
75
76 (setq mail-sources
77 '((directory :path "~/mail/incoming/"
78 :suffix ".in")))
79
80 More information is available in the info doc at Select Methods ->
81 Getting Mail -> Mail Sources
82
83 *** Gnus is now a MIME-capable reader. This affects many parts of
84 Gnus, and adds a slew of new commands. See the manual for details.
85
86 *** Gnus has also been multilingualized. This also affects too many
87 parts of Gnus to summarize here, and adds many new variables.
88 Separate MIME packages like SEMI will not work. There are built-in
89 facilities equivalent to those of gnus-mule.el, which is now just a
90 compatibility layer.
91
92 *** gnus-auto-select-first can now be a function to be
93 called to position point.
94
95 *** The user can now decide which extra headers should be included in
96 summary buffers and NOV files.
97
98 *** `gnus-article-display-hook' has been removed. Instead, a number
99 of variables starting with `gnus-treat-' have been added.
100
101 *** The Gnus posting styles have been redone again and now work in a
102 subtly different manner.
103
104 *** New web-based backends have been added: nnslashdot, nnwarchive
105 and nnultimate. nnweb has been revamped, again, to keep up with
106 ever-changing layouts.
107
108 *** Gnus can now read IMAP mail via nnimap.
109
110 *** There is image support.
111
112 ** When your terminal can't display characters from some of the ISO
113 8859 character sets but can display Latin-1, you can display
114 more-or-less mnemonic sequences of ASCII/Latin-1 characters instead of
115 empty boxes (under a window system) or question marks (not under a
116 window system). Customize the option `latin1-display' to turn this
117 on.
118
119 ** The new user-option `find-file-suppress-same-file-warnings' can be
120 set to suppress warnings ``X and Y are the same file'' when visiting a
121 file that is already visited under a different name.
122
123 ** The new user-option `electric-help-shrink-window' can be set to
124 nil to prevent adjusting the help window size to the buffer size.
125
126 ** Emacs now checks for recursive loads of Lisp files. If the
127 recursion depth exceeds `recursive-load-depth-limit', an error is
128 signaled.
129
130 ** The Strokes package has been updated. If your Emacs has XPM
131 support, you can use it for pictographic editing. In Strokes mode,
132 use C-mouse-2 to compose a complex stoke and insert it into the
133 buffer. You can encode or decode a strokes buffer with new commands
134 M-x strokes-encode-buffer and M-x strokes-decode-buffer. There is a
135 new command M-x strokes-list-strokes.
136
137 +++
138 ** New command M-x describe-character-set reads a character set name
139 and displays information about that.
140
141 ** When an error is signaled during the loading of the user's init
142 file, Emacs now pops up the *Messages* buffer.
143
144 ** Polish and German translations of Emacs' reference card have been
145 added. They are named `pl-refcard.tex' and `de-refcard.tex'.
146 Postscript files are included.
147
148 ** A reference card for Dired has been added. Its name is
149 `dired-ref.tex'.
150
151 ** The new variable `auto-mode-interpreter-regexp' contains a regular
152 expression matching interpreters, for file mode determination.
153
154 This regular expression is matched against the first line of a file to
155 determine the file's mode in `set-auto-mode' when Emacs can't deduce a
156 mode from the file's name. If it matches, the file is assumed to be
157 interpreted by the interpreter matched by the second group of the
158 regular expression. The mode is then determined as the mode
159 associated with that interpreter in `interpreter-mode-alist'.
160
161 +++
162 ** C-down-mouse-3 is bound differently. Now if the menu bar is not
163 displayed it pops up a menu containing the items which would be on the
164 menu bar. If the menu bar is displayed, it pops up the major mode
165 menu or the Edit menu if there is no major mode menu.
166
167 ** Variable `load-path' is no longer customizable because it contains
168 a version-dependent component.
169
170 ** The <delete> function key is now bound to `delete-char' by default.
171 Note that this takes effect only on window systems. On TTYs, Emacs
172 will receive ASCII 127 when the DEL key is pressed. This
173 character is still bound as before.
174
175 ** Item Save Options on the Options menu allows saving options set
176 using that menu.
177
178 ** New function executable-make-buffer-file-executable-if-script-p is
179 suitable as an after-save-hook as an alternative to `executable-chmod'.
180
181 +++
182 ** The most preferred coding-system is now used to save a buffer if
183 buffer-file-coding-system is `undecided' and it is safe for the buffer
184 contents. (The most preferred is set by set-language-environment or
185 by M-x prefer-coding-system.) Thus if you visit an ASCII file and
186 insert a non-ASCII character from your current language environment,
187 the file will be saved silently with the appropriate coding.
188 Previously you would be prompted for a safe coding system.
189
190 +++
191 ** New variable `inhibit-iso-escape-detection' determines if Emacs'
192 coding system detection algorithm should pay attention to ISO2022's
193 escape sequences. If this variable is non-nil, the algorithm ignores
194 such escape sequences. The default value is nil, and it is
195 recommended not to change it except for the special case that you
196 always want to read any escape code verbatim. If you just want to
197 read a specific file without decoding escape codes, use C-x RET c
198 (`universal-coding-system-argument'). For instance, C-x RET c latin-1
199 RET C-x C-f filename RET.
200
201 ** Variable `default-korean-keyboard' is initialized properly from the
202 environment variable `HANGUL_KEYBOARD_TYPE'.
203
204 +++
205 ** C-u C-x = provides detailed information about the character at
206 point in a pop-up window.
207
208 +++
209 ** New command M-x list-charset-chars reads a character set name and
210 displays all characters in that character set.
211
212 ** M-x set-terminal-coding-system (C-x RET t) now allows CCL-based
213 coding systems such as cpXXX and cyrillic-koi8.
214
215 +++
216 ** M-; now calls comment-dwim which tries to do something clever based
217 on the context. M-x kill-comment is now an alias to comment-kill,
218 defined on newcomment.el.
219
220 +++
221 ** The function `getenv' is now callable interactively.
222
223 ** The many obsolete language `setup-...-environment' commands have
224 been removed -- use `set-language-environment'.
225
226 +++
227 ** New user options `display-time-mail-face' and
228 `display-time-use-mail-icon' control the appearance of mode-line mail
229 indicator used by the display-time package. On a suitable display the
230 indicator can be an icon and is mouse-sensitive.
231
232 +++
233 ** Emacs' auto-save list files are now by default stored in a
234 sub-directory `.emacs.d/auto-save-list/' of the user's home directory.
235 (On MS-DOS, this subdirectory's name is `_emacs.d/auto-save.list/'.)
236 You can customize `auto-save-list-prefix' to change this location.
237
238 +++
239 ** On window-systems, additional space can be put between text lines
240 on the display using several methods
241
242 +++
243 - By setting frame parameter `line-spacing' to PIXELS. PIXELS must be
244 a positive integer, and specifies that PIXELS number of pixels should
245 be put below text lines on the affected frame or frames.
246
247 +++
248 - By setting X resource `lineSpacing', class `LineSpacing'. This is
249 equivalent ot specifying the frame parameter.
250
251 - By specifying `--line-spacing=N' or `-lsp N' on the command line.
252
253 - By setting buffer-local variable `line-spacing'. The meaning is
254 the same, but applies to the a particular buffer only.
255
256 +++
257 ** The new command `clone-indirect-buffer' can be used to create
258 an indirect buffer that is a twin copy of the current buffer. The
259 command `clone-indirect-buffer-other-window', bound to C-x 4 c,
260 does the same but displays the indirect buffer in another window.
261
262 +++
263 ** New user options `backup-directory-alist' and
264 `make-backup-file-name-function' control the placement of backups,
265 typically in a single directory or in an invisible sub-directory.
266
267 ** New commands iso-iso2sgml and iso-sgml2iso convert between Latin-1
268 characters and the corresponding SGML (HTML) entities.
269
270 +++
271 ** Emacs now refuses to load compiled Lisp files which weren't
272 compiled with Emacs. Set `load-dangerous-libraries' to t to change
273 this behavior.
274
275 The reason for this change is an incompatible change in XEmacs' byte
276 compiler. Files compiled with XEmacs can contain byte codes that let
277 Emacs dump core.
278
279 +++
280 ** New X resources recognized
281
282 *** The X resource `synchronous', class `Synchronous', specifies
283 whether Emacs should run in synchronous mode. Synchronous mode
284 is useful for debugging X problems.
285
286 Example:
287
288 emacs.synchronous: true
289
290 *** The X resource `visualClass, class `VisualClass', specifies the
291 visual Emacs should use. The resource's value should be a string of
292 the form `CLASS-DEPTH', where CLASS is the name of the visual class,
293 and DEPTH is the requested color depth as a decimal number. Valid
294 visual class names are
295
296 TrueColor
297 PseudoColor
298 DirectColor
299 StaticColor
300 GrayScale
301 StaticGray
302
303 Visual class names specified as X resource are case-insensitive, i.e.
304 `pseudocolor', `Pseudocolor' and `PseudoColor' all have the same
305 meaning.
306
307 The program `xdpyinfo' can be used to list the visual classes
308 supported on your display, and which depths they have. If
309 `visualClass' is not specified, Emacs uses the display's default
310 visual.
311
312 Example:
313
314 emacs.visualClass: TrueColor-8
315
316 *** The X resource `privateColormap', class `PrivateColormap',
317 specifies that Emacs should use a private colormap if it is using the
318 default visual, and that visual is of class PseudoColor. Recognized
319 resource values are `true' or `on'.
320
321 Example:
322
323 emacs.privateColormap: true
324
325 ** The menu bar configuration has changed. The new configuration is
326 more CUA-compliant. The most significant change is that Options is
327 now a separate menu-bar item, with Mule and Customize as its submenus.
328
329 ** User-option `show-cursor-in-non-selected-windows' controls how to
330 display the cursor in non-selected windows. If nil, no cursor is
331 shown, if non-nil a hollow box cursor is shown. This option can
332 be customized.
333
334 +++
335 ** The variable `echo-keystrokes' may now have a floating point value.
336
337 +++
338 ** C-x 5 1 runs the new command delete-other-frames which deletes
339 all frames except the selected one.
340
341 ** If your init file is compiled (.emacs.elc), `user-init-file' is set
342 to the source name (.emacs.el), if that exists, after loading it.
343
344 ** The help string specified for a menu-item whose definition contains
345 the property `:help HELP' is now displayed under X, on MS-Windows, and
346 MS-DOS, either in the echo area or with tooltips. Many standard menus
347 displayed by Emacs now have help strings.
348
349 +++
350 ** Highlighting of mouse-sensitive regions is now supported in the
351 MS-DOS version of Emacs.
352
353 ** New user option `read-mail-command' specifies a command to use to
354 read mail from the menu etc.
355
356 +++
357 ** Hexl contains a new command `hexl-insert-hex-string' which inserts
358 a string of hexadecimal numbers read from the mini-buffer.
359
360 ** Changes in Texinfo mode.
361
362 ** A couple of new key bindings have been added for inserting Texinfo
363 macros
364
365 Key binding Macro
366 -------------------------
367 C-c C-c C-s @strong
368 C-c C-c C-e @emph
369 C-c C-c u @url
370 C-c C-c q @quotation
371 C-c C-c m @email
372
373 ** Changes in Outline mode.
374
375 There is now support for Imenu to index headings. A new command
376 `outline-headers-as-kill' copies the visible headings in the region to
377 the kill ring, e.g. to produce a table of contents.
378
379 ** Changes to Emacs Server
380
381 +++
382 *** The new option `server-kill-new-buffers' specifies what to do
383 with buffers when done with them. If non-nil, the default, buffers
384 are killed, unless they were already present before visiting them with
385 Emacs Server. If nil, `server-temp-file-regexp' specifies which
386 buffers to kill, as before.
387
388 Please note that only buffers are killed that still have a client,
389 i.e. buffers visited with `emacsclient --no-wait' are never killed in
390 this way.
391
392 ** Changes to Show Paren mode.
393
394 *** Overlays used by Show Paren mode now use a priority property.
395 The new user option show-paren-priority specifies the priority to
396 use. Default is 1000.
397
398 +++
399 ** New command M-x check-parens can be used to find unbalanced paren
400 groups and strings in buffers in Lisp mode (or other modes).
401
402 +++
403 ** You can now easily create new *Info* buffers using either
404 M-x clone-buffer, C-u m <entry> RET or C-u g <entry> RET.
405 M-x clone-buffer can also be used on *Help* and several other special
406 buffers.
407
408 +++
409 ** Emacs can now support 'wheeled' mice (such as the MS IntelliMouse)
410 under XFree86. To enable this, simply put (mwheel-install) in your
411 .emacs file.
412
413 The variables `mwheel-follow-mouse' and `mwheel-scroll-amount'
414 determine where and by how much buffers are scrolled.
415
416 ** Listing buffers with M-x list-buffers (C-x C-b) now shows
417 abbreviated file names. Abbreviations can be customized by changing
418 `directory-abbrev-alist'.
419
420 ** Faces and frame parameters.
421
422 There are four new faces `scroll-bar', `border', `cursor' and `mouse'.
423 Setting the frame parameters `scroll-bar-foreground' and
424 `scroll-bar-background' sets foreground and background color of face
425 `scroll-bar' and vice versa. Setting frame parameter `border-color'
426 sets the background color of face `border' and vice versa. Likewise
427 for frame parameters `cursor-color' and face `cursor', and frame
428 parameter `mouse-color' and face `mouse'.
429
430 Changing frame parameter `font' sets font-related attributes of the
431 `default' face and vice versa. Setting frame parameters
432 `foreground-color' or `background-color' sets the colors of the
433 `default' face and vice versa.
434
435 +++
436 ** New face `menu'.
437
438 The face `menu' can be used to change colors and font of Emacs' menus.
439 Setting the font of LessTif/Motif menus is currently not supported;
440 attempts to set the font are ignored in this case.
441
442 +++
443 ** New frame parameter `screen-gamma' for gamma correction.
444
445 The new frame parameter `screen-gamma' specifies gamma-correction for
446 colors. Its value may be nil, the default, in which case no gamma
447 correction occurs, or a number > 0, usually a float, that specifies
448 the screen gamma of a frame's display.
449
450 PC monitors usually have a screen gamma of 2.2. smaller values result
451 in darker colors. You might want to try a screen gamma of 1.5 for LCD
452 color displays. The viewing gamma Emacs uses is 0.4545. (1/2.2).
453
454 The X resource name of this parameter is `screenGamma', class
455 `ScreenGamma'.
456
457 ** Emacs has a new redisplay engine.
458
459 The new redisplay handles characters of variable width and height.
460 Italic text can be used without redisplay problems. Fonts containing
461 oversized characters, i.e. characters larger than the logical height
462 of a font can be used. Images of various formats can be displayed in
463 the text.
464
465 ** Emacs has a new face implementation.
466
467 The new faces no longer fundamentally use X font names to specify the
468 font. Instead, each face has several independent attributes--family,
469 height, width, weight and slant--that it may or may not specify.
470 These attributes can be merged from various faces, and then together
471 specify a font.
472
473 Faces are supported on terminals that can display color or fonts.
474 These terminal capabilities are auto-detected. Details can be found
475 under Lisp changes, below.
476
477 ** New default font is Courier 12pt.
478
479 +++
480 ** When using a windowing terminal, each Emacs window now has a cursor
481 of its own. When the window is selected, the cursor is solid;
482 otherwise, it is hollow.
483
484 ** Bitmap areas to the left and right of windows are used to display
485 truncation marks, continuation marks, overlay arrows and alike. The
486 foreground, background, and stipple of these areas can be changed by
487 customizing face `fringe'.
488
489 ** The mode line under X is now drawn with shadows by default. You
490 can change its appearance by modifying the face `modeline'.
491
492 ** LessTif support.
493
494 Emacs now runs with the LessTif toolkit (see <http://www.lesstif.org>).
495 You will need a version 0.88.1 or later.
496
497 ** Toolkit scroll bars.
498
499 Emacs now uses toolkit scrollbars if available. When configured for
500 LessTif/Motif, it will use that toolkit's scrollbar. Otherwise, when
501 configured for Lucid and Athena widgets, it will use the Xaw3d scroll
502 bar if Xaw3d is available. You can turn off the use of toolkit scroll
503 bars by specifying `--with-toolkit-scroll-bars=no' when configuring
504 Emacs.
505
506 When you encounter problems with the Xaw3d scroll bar, watch out how
507 Xaw3d is compiled on your system. If the Makefile generated from
508 Xaw3d's Imakefile contains a `-DNARROWPROTO' compiler option, and your
509 Emacs system configuration file `s/your-system.h' does not contain a
510 define for NARROWPROTO, you might consider adding it. Take
511 `s/freebsd.h' as an example.
512
513 Alternatively, if you don't have access to the Xaw3d source code, take
514 a look at your system's imake configuration file, for example in the
515 directory `/usr/X11R6/lib/X11/config' (paths are different on
516 different systems). You will find files `*.cf' there. If your
517 system's cf-file contains a line like `#define NeedWidePrototypes NO',
518 add a `#define NARROWPROTO' to your Emacs system configuration file.
519
520 The reason for this is that one Xaw3d function uses `double' or
521 `float' function parameters depending on the setting of NARROWPROTO.
522 This is not a problem when Imakefiles are used because each system's
523 image configuration file contains the necessary information. Since
524 Emacs doesn't use imake, this has do be done manually.
525
526 ** Toggle buttons and radio buttons in menus.
527
528 When compiled with LessTif (or Motif) support, Emacs uses toolkit
529 widgets for radio and toggle buttons in menus. When configured for
530 Lucid, Emacs draws radio buttons and toggle buttons similar to Motif.
531
532 +++
533 ** Highlighting of trailing whitespace.
534
535 When `show-trailing-whitespace' is non-nil, Emacs displays trailing
536 whitespace in the face `trailing-whitespace'. Trailing whitespace is
537 defined as spaces or tabs at the end of a line. To avoid busy
538 highlighting when entering new text, trailing whitespace is not
539 displayed if point is at the end of the line containing the
540 whitespace.
541
542 +++
543 ** Busy-cursor.
544
545 Emacs can optionally display a busy-cursor under X. You can turn the
546 display on or off by customizing group `cursor'.
547
548 +++
549 ** Blinking cursor
550
551 M-x blink-cursor-mode toggles a blinking cursor under X and on
552 terminals having terminal capabilities `vi', `vs', and `ve'. Blinking
553 and related parameters like frequency and delay can be customized in
554 the group `cursor'.
555
556 ** New font-lock support mode `jit-lock-mode'.
557
558 This support mode is roughly equivalent to `lazy-lock' but is
559 generally faster. It supports stealth and deferred fontification.
560 See the documentation of the function `jit-lock-mode' for more
561 details.
562
563 Font-lock uses jit-lock-mode as default support mode, so you don't
564 have to do anything to activate it.
565
566 ** Tabs and variable-width text.
567
568 Tabs are now displayed with stretch properties; the width of a tab is
569 defined as a multiple of the normal character width of a frame, and is
570 independent of the fonts used in the text where the tab appears.
571 Thus, tabs can be used to line up text in different fonts.
572
573 ** Enhancements of the Lucid menu bar
574
575 +++
576 *** The Lucid menu bar now supports the resource "margin".
577
578 emacs.pane.menubar.margin: 5
579
580 The default margin is 4 which makes the menu bar appear like the
581 LessTif/Motif one.
582
583 *** Arrows that indicate sub-menus are now drawn with shadows, as in
584 LessTif and Motif.
585
586 +++
587 ** Hscrolling in C code.
588
589 Horizontal scrolling now happens automatically if
590 `automatic-hscrolling' is set (the default). This setting can be
591 customized.
592
593 ** Tool bar support.
594
595 Emacs supports a tool bar at the top of a frame under X. For details
596 how to define a tool bar, see the page describing Lisp-level changes.
597 Tool-bar global minor mode controls whether or not it is displayed.
598 To make the tool bar more useful, we need contributions of extra icons
599 for specific modes (with copyright assignments).
600
601 +++
602 ** Mouse-sensitive mode line.
603
604 Different parts of the mode line under X have been made
605 mouse-sensitive. Moving the mouse to a mouse-sensitive part in the mode
606 line changes the appearance of the mouse pointer to an arrow, and help
607 about available mouse actions is displayed either in the echo area, or
608 in the tooltip window if you have enabled one.
609
610 Currently, the following actions have been defined:
611
612 - Mouse-1 on the buffer name in the mode line switches between two
613 buffers.
614
615 - Mouse-2 on the buffer-name switches to the next buffer, and
616 M-mouse-2 switches to the previous buffer in the buffer list.
617
618 - Mouse-3 on the buffer-name displays a buffer menu.
619
620 - Mouse-2 on the read-only or modified status in the mode line (`%' or
621 `*') toggles the status.
622
623 - Mouse-3 on the mode name display a minor-mode menu.
624
625 ** LessTif/Motif file selection dialog.
626
627 When Emacs is configured to use LessTif or Motif, reading a file name
628 from a menu will pop up a file selection dialog if `use-dialog-box' is
629 non-nil.
630
631 ** Emacs can display faces on TTY frames.
632
633 Emacs automatically detects terminals that are able to display colors.
634 Faces with a weight greater than normal are displayed extra-bright, if
635 the terminal supports it. Faces with a weight less than normal and
636 italic faces are displayed dimmed, if the terminal supports it.
637 Underlined faces are displayed underlined if possible. Other face
638 attributes such as `overline', `strike-through', and `box' are ignored
639 on terminals.
640
641 ** Sound support
642
643 Emacs supports playing sound files on GNU/Linux and FreeBSD (Voxware
644 driver and native BSD driver, a.k.a. Luigi's driver). Currently
645 supported file formats are RIFF-WAVE (*.wav) and Sun Audio (*.au).
646
647 +++
648 ** A new variable, backup-by-copying-when-privileged-mismatch, gives
649 the highest file uid for which backup-by-copying-when-mismatch will be
650 forced on. The assumption is that uids less than or equal to this
651 value are special uids (root, bin, daemon, etc.--not real system
652 users) and that files owned by these users should not change ownership,
653 even if your system policy allows users other than root to edit them.
654
655 The default is 200; set the variable to nil to disable the feature.
656
657 +++
658 ** A block cursor can be drawn as wide as the glyph under it under X.
659
660 As an example: if a block cursor is over a tab character, it will be
661 drawn as wide as that tab on the display. To do this, set
662 `x-stretch-cursor' to a non-nil value.
663
664 +++
665 ** Empty display lines at the end of a buffer may be marked with a
666 bitmap (this is similar to the tilde displayed by vi).
667
668 This behavior is activated by setting the buffer-local variable
669 `indicate-empty-lines' to a non-nil value. The default value of this
670 variable is found in `default-indicate-empty-lines'.
671
672 +++
673 ** There is a new "aggressive" scrolling method.
674
675 When scrolling up because point is above the window start, if the
676 value of the buffer-local variable `scroll-up-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 top of the window.
679
680 When scrolling down because point is below the window end, if the
681 value of the buffer-local variable `scroll-down-aggessively' is a
682 number, Emacs chooses a new window start so that point ends up that
683 fraction of the window's height from the bottom of the window.
684
685 ** The rectangle commands now avoid inserting undesirable spaces,
686 notably at the end of lines.
687
688 All these functions have been rewritten to avoid inserting unwanted
689 spaces, and an optional prefix now allows them to behave the old way.
690
691 +++
692 There is a new command M-x replace-rectangle.
693
694 ** The new command M-x query-replace-regexp-eval acts like
695 query-replace-regexp, but takes a Lisp expression which is evaluated
696 after each match to get the replacement text.
697
698 +++
699 ** M-x query-replace recognizes a new command `e' (or `E') that lets
700 you edit the replacement string.
701
702 ** The new command mail-abbrev-complete-alias, bound to `M-TAB', lets
703 you complete mail aliases in the text, analogous to
704 lisp-complete-symbol.
705
706 +++
707 ** Emacs now resizes mini-windows if appropriate.
708
709 If a message is longer than one line, or minibuffer contents are
710 longer than one line, Emacs now resizes the minibuffer window unless
711 it is on a frame of its own. You can control the maximum minibuffer
712 window size by setting the following variable:
713
714 - User option: max-mini-window-height
715
716 Maximum height for resizing mini-windows. If a float, it specifies a
717 fraction of the mini-window frame's height. If an integer, it
718 specifies a number of lines. If nil, don't resize.
719
720 Default is 0.25.
721
722 ** The command `Info-search' now uses a search history.
723
724 ** Changes to hideshow.el
725
726 Hideshow is now at version 5.x. It uses a new algorithms for block
727 selection and traversal, includes more isearch support, and has more
728 conventional keybindings.
729
730 *** Generalized block selection and traversal
731
732 A block is now recognized by three things: its start and end regexps
733 (both strings), and a match-data selector (an integer) specifying
734 which sub-expression in the start regexp serves as the place where a
735 `forward-sexp'-like function can operate. Hideshow always adjusts
736 point to this sub-expression before calling `hs-forward-sexp-func'
737 (which for most modes evaluates to `forward-sexp').
738
739 If the match-data selector is not specified, it defaults to zero,
740 i.e., the entire start regexp is valid, w/ no prefix. This is
741 backwards compatible with previous versions of hideshow. Please see
742 the docstring for variable `hs-special-modes-alist' for details.
743
744 *** Isearch support for updating mode line
745
746 During incremental search, if Hideshow minor mode is active, hidden
747 blocks are temporarily shown. The variable `hs-headline' records the
748 line at the beginning of the opened block (preceding the hidden
749 portion of the buffer), and the mode line is refreshed. When a block
750 is re-hidden, the variable is set to nil.
751
752 To show `hs-headline' in the mode line, you may wish to include
753 something like this in your .emacs.
754
755 (add-hook 'hs-minor-mode-hook
756 (lambda ()
757 (add-to-list 'mode-line-format 'hs-headline)))
758
759 *** New customization var: `hs-hide-all-non-comment-function'
760
761 Normally, `hs-hide-all' hides everything, leaving only the
762 header lines of top-level forms (and comments, unless var
763 `hs-hide-comments-when-hiding-all' is non-nil). It does this by
764 moving point to each top-level block beginning and hiding the
765 block there. In some major modes (for example, Java), this
766 behavior results in few blocks left visible, which may not be so
767 useful.
768
769 You can now set var `hs-hide-all-non-comment-function' to a
770 function to be called at each top-level block beginning, instead
771 of the normal block-hiding function. For example, the following
772 code defines a function to hide one level down and move point
773 appropriately, and then tells hideshow to use the new function.
774
775 (defun ttn-hs-hide-level-1 ()
776 (hs-hide-level 1)
777 (forward-sexp 1))
778 (setq hs-hide-all-non-comment-function 'ttn-hs-hide-level-1)
779
780 The name `hs-hide-all-non-comment-function' was chosen to
781 emphasize that this function is not called for comment blocks,
782 only for code blocks.
783
784 *** Command deleted: `hs-show-region'
785
786 Historical Note: This command was added to handle "unbalanced
787 parentheses" emergencies back when hideshow.el used selective
788 display for implementation.
789
790 *** Commands rebound to more conventional keys
791
792 The hideshow commands used to be bound to keys of the form "C-c
793 LETTER". This is contrary to the Emacs keybinding convention,
794 which reserves that space for user modification. Here are the
795 new bindings (which includes the addition of `hs-toggle-hiding'):
796
797 hs-hide-block C-c C-h
798 hs-show-block C-c C-s
799 hs-hide-all C-c C-M-h
800 hs-show-all C-c C-M-s
801 hs-hide-level C-c C-l
802 hs-toggle-hiding C-c C-c
803 hs-mouse-toggle-hiding [(shift button-2)]
804
805 These were chosen to roughly imitate those used by Outline mode.
806
807 ** Changes to Change Log mode and Add-Log functions
808
809 +++
810 *** If you invoke `add-change-log-entry' from a backup file, it makes
811 an entry appropriate for the file's parent. This is useful for making
812 log entries by comparing a version with deleted functions.
813
814 +++
815 **** New command M-x change-log-merge merges another log into the
816 current buffer.
817
818 +++
819 *** New command M-x change-log-redate fixes any old-style date entries
820 in a log file.
821
822 +++
823 *** Change Log mode now adds a file's version number to change log
824 entries if user-option `change-log-version-info-enabled' is non-nil.
825
826 +++
827 *** Unless the file is under version control the search for a file's
828 version number is performed based on regular expressions from
829 `change-log-version-number-regexp-list' which can be cutomized.
830 Version numbers are only found in the first 10 percent of a file.
831
832 *** Change Log mode now defines its own faces for font-lock
833 highlighting.
834
835 ** Changes in Font Lock
836
837 *** The new function `font-lock-remove-keywords' can be used to remove
838 font-lock keywords from the current buffer or from a specific major
839 mode.
840
841 ** Comint (subshell) changes
842
843 By default, comint no longer uses the variable `comint-prompt-regexp' to
844 distinguish prompts from user-input. Instead, it notices which parts of
845 the text were output by the process, and which entered by the user, and
846 attaches `field' properties to allow emacs commands to use this information.
847 Common movement commands, notably beginning-of-line, respect field
848 boundaries in a fairly natural manner.
849 To disable this feature, and use the old behavior, set the variable
850 `comint-use-prompt-regexp-instead-of-fields' to a non-nil value.
851
852 Comint now includes new features to send commands to running processes
853 and redirect the output to a designated buffer or buffers.
854
855 The command M-x comint-redirect-send-command reads a command and
856 buffer name from the mini-buffer. The command is sent to the current
857 buffer's process, and its output is inserted into the specified buffer.
858
859 The command M-x comint-redirect-send-command-to-process acts like
860 M-x comint-redirect-send-command but additionally reads the name of
861 the buffer whose process should be used from the mini-buffer.
862
863 Packages based on comint.el like shell-mode, and scheme-interaction-mode
864 now highlight user input and program prompts, and support choosing
865 previous input with mouse-2. To control these feature, see the
866 user-options `comint-highlight-input' and `comint-highlight-prompt'.
867
868 ** Changes to Rmail mode
869
870 *** The new user-option rmail-rmail-user-mail-address-regexp can be
871 set to fine tune the identification of of the correspondent when
872 receiving new mail. If it matches the address of the sender, the
873 recipient is taken as correspondent of a mail. If nil, the default,
874 `user-login-name' and `user-mail-address' are used to exclude yourself
875 as correspondent.
876
877 Usually you don't have to set this variable, except if you collect
878 mails sent by you under different user names. Then it should be a
879 regexp matching your mail addresses.
880
881 *** The new user-option rmail-confirm-expunge controls whether and how
882 to ask for confirmation before expunging deleted messages from an
883 Rmail file. You can choose between no confirmation, confirmation
884 with y-or-n-p, or confirmation with yes-or-no-p. Default is to ask
885 for confirmation with yes-or-no-p.
886
887 *** RET is now bound in the Rmail summary to rmail-summary-goto-msg,
888 like `j'.
889
890 *** There is a new user option `rmail-digest-end-regexps' that
891 specifies the regular expressions to detect the line that ends a
892 digest message.
893
894 *** The new user option `rmail-automatic-folder-directives' specifies
895 in which folder to put messages automatically.
896
897 ** Changes to TeX mode
898
899 The default mode has been changed from `plain-tex-mode' to
900 `latex-mode'.
901
902 ** Changes to RefTeX mode
903
904 *** RefTeX has new support for index generation. Index entries can be
905 created with `C-c <', with completion available on index keys.
906 Pressing `C-c /' indexes the word at the cursor with a default
907 macro. `C-c >' compiles all index entries into an alphabetically
908 sorted *Index* buffer which looks like the final index. Entries
909 can be edited from that buffer.
910
911 *** Label and citation key selection now allow to select several
912 items and reference them together (use `m' to mark items, `a' or
913 `A' to use all marked entries).
914
915 *** reftex.el has been split into a number of smaller files to reduce
916 memory use when only a part of RefTeX is being used.
917
918 *** a new command `reftex-view-crossref-from-bibtex' (bound to `C-c &'
919 in BibTeX-mode) can be called in a BibTeX database buffer in order
920 to show locations in LaTeX documents where a particular entry has
921 been cited.
922
923 ** Emacs Lisp mode now allows multiple levels of outline headings.
924 The level of a heading is determined from the number of leading
925 semicolons in a heading line. Toplevel forms starting with a `('
926 in column 1 are always made leaves.
927
928 ** The M-x time-stamp command (most commonly used on write-file-hooks)
929 has the following new features:
930
931 *** The patterns for finding the time stamp and for updating a pattern
932 may match text spanning multiple lines. For example, some people like
933 to have the filename and date on separate lines. The new variable
934 time-stamp-inserts-lines controls the matching for multi-line patterns.
935
936 *** More than one time stamp can be updated in the same file. This
937 feature is useful if you need separate time stamps in a program source
938 file to both include in formatted documentation and insert in the
939 compiled binary. The same time-stamp will be written at each matching
940 pattern. The variable time-stamp-count enables this new feature; it
941 defaults to 1.
942
943 ** Partial Completion mode now completes environment variables in
944 file names.
945
946 +++
947 ** Tooltips.
948
949 Tooltips are small X windows displaying a help string at the current
950 mouse position. To use them, use the Lisp package `tooltip' which you
951 can access via the user option `tooltip-mode'.
952
953 Tooltips also provides support for GUD debugging. If activated,
954 variable values can be displayed in tooltips by pointing at them with
955 the mouse in source buffers. You can customize various aspects of the
956 tooltip display in the group `tooltip'.
957
958 +++
959 ** Customize changes
960
961 *** Customize now supports comments about customized items. Use the
962 `State' menu to add comments. Note that customization comments will
963 cause the customizations to fail in earlier versions of Emacs.
964
965 *** The new option `custom-buffer-done-function' says whether to kill
966 Custom buffers when you've done with them or just bury them (the
967 default).
968
969 *** The keyword :set-after in defcustom allows to specify dependencies
970 between custom options. Example:
971
972 (defcustom default-input-method nil
973 "*Default input method for multilingual text (a string).
974 This is the input method activated automatically by the command
975 `toggle-input-method' (\\[toggle-input-method])."
976 :group 'mule
977 :type '(choice (const nil) string)
978 :set-after '(current-language-environment))
979
980 This specifies that default-input-method should be set after
981 current-language-environment even if default-input-method appears
982 first in a custom-set-variables statement.
983
984 ** New features in evaluation commands
985
986 *** The commands to evaluate Lisp expressions, such as C-M-x in Lisp
987 modes, C-j in Lisp Interaction mode, and M-:, now bind the variables
988 print-level, print-length, and debug-on-error based on the
989 customizable variables eval-expression-print-level,
990 eval-expression-print-length, and eval-expression-debug-on-error.
991
992 *** The function `eval-defun' (M-C-x) now loads Edebug and instruments
993 code when called with a prefix argument.
994
995 ** Ispell changes
996
997 +++
998 *** The command `ispell' now spell-checks a region if
999 transient-mark-mode is on, and the mark is active. Otherwise it
1000 spell-checks the current buffer.
1001
1002 +++
1003 *** Support for synchronous subprocesses - DOS/Windoze - has been
1004 added.
1005
1006 *** An "alignment error" bug was fixed when a manual spelling
1007 correction is made and re-checked.
1008
1009 *** An Italian and a Portuguese dictionary definition has been added.
1010
1011 *** Region skipping performance has been vastly improved in some
1012 cases.
1013
1014 *** Spell checking HTML buffers has been improved and isn't so strict
1015 on syntax errors.
1016
1017 *** The buffer-local words are now always placed on a new line at the
1018 end of the buffer.
1019
1020 ** Dired changes
1021
1022 *** New variable `dired-recursive-deletes' determines if the delete
1023 command will delete non-empty directories recursively. The default
1024 is, delete only empty directories.
1025
1026 *** New variable `dired-recursive-copies' determines if the copy
1027 command will copy directories recursively. The default is, do not
1028 copy directories recursively.
1029
1030 *** In command `dired-do-shell-command' (usually bound to `!') a `?'
1031 in the shell command has a special meaning similar to `*', but with
1032 the difference that the command will be run on each file individually.
1033
1034 *** The new command `dired-find-alternate-file' (usually bound to `a')
1035 replaces the Dired buffer with the buffer for an alternate file or
1036 directory.
1037
1038 *** The new command `dired-show-file-type' (usually bound to `w') shows
1039 a message in the echo area describing what type of file the point is on.
1040 This command invokes the external program `file' do its work, and so
1041 will only work on systems with that program, and will be only as
1042 accurate or inaccurate as it is.
1043
1044 *** Dired now properly handles undo changes of adding/removing `-R'
1045 from ls switches.
1046
1047 ** The variable mail-specify-envelope-from controls whether to
1048 use the -f option when sending mail.
1049
1050 ** CC mode changes.
1051
1052 Note: This release contains changes that might not be compatible with
1053 current user setups (although it's believed that these
1054 incompatibilities will only show in very uncommon circumstances).
1055 However, since the impact is uncertain, these changes may be rolled
1056 back depending on user feedback. Therefore there's no forward
1057 compatibility guarantee wrt the new features introduced in this
1058 release.
1059
1060 *** c-style-variables-are-local-p now defaults to t.
1061 This is an incompatible change that has been made to make the behavior
1062 of the style system wrt global variable settings less confusing for
1063 non-advanced users. If you know what this variable does you might
1064 want to set it to nil in your .emacs, otherwise you probably don't
1065 have to bother.
1066
1067 Defaulting c-style-variables-are-local-p to t avoids the confusing
1068 situation that occurs when a user sets some style variables globally
1069 and edits both a Java and a non-Java file in the same Emacs session.
1070 If the style variables aren't buffer local in this case, loading of
1071 the second file will cause the default style (either "gnu" or "java"
1072 by default) to override the global settings made by the user.
1073
1074 *** New initialization procedure for the style system.
1075 When the initial style for a buffer is determined by CC Mode (from the
1076 variable c-default-style), the global values of style variables now
1077 take precedence over the values specified by the chosen style. This
1078 is different than the old behavior: previously, the style-specific
1079 settings would override the global settings. This change makes it
1080 possible to do simple configuration in the intuitive way with
1081 Customize or with setq lines in one's .emacs file.
1082
1083 By default, the global value of every style variable is the new
1084 special symbol set-from-style, which causes the value to be taken from
1085 the style system. This means that in effect, only an explicit setting
1086 of a style variable will cause the "overriding" behavior described
1087 above.
1088
1089 Also note that global settings override style-specific settings *only*
1090 when the initial style of a buffer is chosen by a CC Mode major mode
1091 function. When a style is chosen in other ways --- for example, by a
1092 call like (c-set-style "gnu") in a hook, or via M-x c-set-style ---
1093 then the style-specific values take precedence over any global style
1094 values. In Lisp terms, global values override style-specific values
1095 only when the new second argument to c-set-style is non-nil; see the
1096 function documentation for more info.
1097
1098 The purpose of these changes is to make it easier for users,
1099 especially novice users, to do simple customizations with Customize or
1100 with setq in their .emacs files. On the other hand, the new system is
1101 intended to be compatible with advanced users' customizations as well,
1102 such as those that choose styles in hooks or whatnot. This new system
1103 is believed to be almost entirely compatible with current
1104 configurations, in spite of the changed precedence between style and
1105 global variable settings when a buffer's default style is set.
1106
1107 (Thanks to Eric Eide for clarifying this explanation a bit.)
1108
1109 **** c-offsets-alist is now a customizable variable.
1110 This became possible as a result of the new initialization behavior.
1111
1112 This variable is treated slightly differently from the other style
1113 variables; instead of using the symbol set-from-style, it will be
1114 completed with the syntactic symbols it doesn't already contain when
1115 the style is first initialized. This means it now defaults to the
1116 empty list to make all syntactic elements get their values from the
1117 style system.
1118
1119 **** Compatibility variable to restore the old behavior.
1120 In case your configuration doesn't work with this change, you can set
1121 c-old-style-variable-behavior to non-nil to get the old behavior back
1122 as far as possible.
1123
1124 *** Improvements to line breaking and text filling.
1125 CC Mode now handles this more intelligently and seamlessly wrt the
1126 surrounding code, especially inside comments. For details see the new
1127 chapter about this in the manual.
1128
1129 **** New variable to recognize comment line prefix decorations.
1130 The variable c-comment-prefix-regexp has been added to properly
1131 recognize the line prefix in both block and line comments. It's
1132 primarily used to initialize the various paragraph recognition and
1133 adaptive filling variables that the text handling functions uses.
1134
1135 **** New variable c-block-comment-prefix.
1136 This is a generalization of the now obsolete variable
1137 c-comment-continuation-stars to handle arbitrary strings.
1138
1139 **** CC Mode now uses adaptive fill mode.
1140 This to make it adapt better to the paragraph style inside comments.
1141
1142 It's also possible to use other adaptive filling packages inside CC
1143 Mode, notably Kyle E. Jones' Filladapt mode (http://wonderworks.com/).
1144 A new convenience function c-setup-filladapt sets up Filladapt for use
1145 inside CC Mode.
1146
1147 Note though that the 2.12 version of Filladapt lacks a feature that
1148 causes it to work suboptimally when c-comment-prefix-regexp can match
1149 the empty string (which it commonly does). A patch for that is
1150 available from the CC Mode web site (http://www.python.org/emacs/
1151 cc-mode/).
1152
1153 **** It's now possible to selectively turn off auto filling.
1154 The variable c-ignore-auto-fill is used to ignore auto fill mode in
1155 specific contexts, e.g. in preprocessor directives and in string
1156 literals.
1157
1158 **** New context sensitive line break function c-context-line-break.
1159 It works like newline-and-indent in normal code, and adapts the line
1160 prefix according to the comment style when used inside comments. If
1161 you're normally using newline-and-indent, you might want to switch to
1162 this function.
1163
1164 *** Fixes to IDL mode.
1165 It now does a better job in recognizing only the constructs relevant
1166 to IDL. E.g. it no longer matches "class" as the beginning of a
1167 struct block, but it does match the CORBA 2.3 "valuetype" keyword.
1168 Thanks to Eric Eide.
1169
1170 *** Improvements to the Whitesmith style.
1171 It now keeps the style consistently on all levels and both when
1172 opening braces hangs and when they don't.
1173
1174 **** New lineup function c-lineup-whitesmith-in-block.
1175
1176 *** New lineup functions c-lineup-template-args and c-indent-multi-line-block.
1177 See their docstrings for details. c-lineup-template-args does a
1178 better job of tracking the brackets used as parens in C++ templates,
1179 and is used by default to line up continued template arguments.
1180
1181 *** c-lineup-comment now preserves alignment with a comment on the
1182 previous line. It used to instead preserve comments that started in
1183 the column specified by comment-column.
1184
1185 *** c-lineup-C-comments handles "free form" text comments.
1186 In comments with a long delimiter line at the start, the indentation
1187 is kept unchanged for lines that start with an empty comment line
1188 prefix. This is intended for the type of large block comments that
1189 contain documentation with its own formatting. In these you normally
1190 don't want CC Mode to change the indentation.
1191
1192 *** The `c' syntactic symbol is now relative to the comment start
1193 instead of the previous line, to make integers usable as lineup
1194 arguments.
1195
1196 *** All lineup functions have gotten docstrings.
1197
1198 *** More preprocessor directive movement functions.
1199 c-down-conditional does the reverse of c-up-conditional.
1200 c-up-conditional-with-else and c-down-conditional-with-else are
1201 variants of these that also stops at "#else" lines (suggested by Don
1202 Provan).
1203
1204 *** Minor improvements to many movement functions in tricky situations.
1205
1206 ** Makefile mode changes
1207
1208 *** The mode now uses the abbrev table `makefile-mode-abbrev-table'.
1209
1210 *** Conditionals and include statements are now highlighted when
1211 Fontlock mode is active.
1212
1213 ** Isearch changes
1214
1215 *** Isearch now puts a call to `isearch-resume' in the command history,
1216 so that searches can be resumed.
1217
1218 *** In Isearch mode, M-C-s and M-C-r are now bound like C-s and C-r,
1219 respectively, i.e. you can repeat a regexp isearch with the same keys
1220 that started the search.
1221
1222 *** In Isearch mode, mouse-2 in the echo area now yanks the current
1223 selection into the search string rather than giving an error.
1224
1225 +++
1226 *** There is a new lazy highlighting feature in incremental search.
1227
1228 Lazy highlighting is switched on/off by customizing variable
1229 `isearch-lazy-highlight'. When active, all matches for the current
1230 search string are highlighted. The current match is highlighted as
1231 before using face `isearch' or `region'. All other matches are
1232 highlighted using face `isearch-lazy-highlight-face' which defaults to
1233 `secondary-selection'.
1234
1235 The extra highlighting makes it easier to anticipate where the cursor
1236 will end up each time you press C-s or C-r to repeat a pending search.
1237 Highlighting of these additional matches happens in a deferred fashion
1238 using "idle timers," so the cycles needed do not rob isearch of its
1239 usual snappy response.
1240
1241 If `isearch-lazy-highlight-cleanup' is set to t, highlights for
1242 matches are automatically cleared when you end the search. If it is
1243 set to nil, you can remove the highlights manually with `M-x
1244 isearch-lazy-highlight-cleanup'.
1245
1246 +++
1247 ** Changes in sort.el
1248
1249 The function sort-numeric-fields interprets numbers starting with `0'
1250 as octal and numbers starting with `0x' or `0X' as hexadecimal. The
1251 new user-option sort-numeric-base can be used to specify a default
1252 numeric base.
1253
1254 ** Changes to Ange-ftp
1255
1256 +++
1257 *** Ange-ftp allows you to specify of a port number in remote file
1258 names cleanly. It is appended to the host name, separated by a hash
1259 sign, e.g. `/foo@bar.org#666:mumble'. (This syntax comes from EFS.)
1260
1261 *** If the new user-option `ange-ftp-try-passive-mode' is set, passive
1262 ftp mode will be used if the ftp client supports that.
1263
1264 *** Ange-ftp handles the output of the w32-style clients which
1265 output ^M at the end of lines.
1266
1267 ** Shell script mode changes.
1268
1269 Shell script mode (sh-script) can now indent scripts for shells
1270 derived from sh and rc. The indentation style is customizeable, and
1271 sh-script can attempt to "learn" the current buffer's style.
1272
1273 ** Etags changes.
1274
1275 *** In DOS, etags looks for file.cgz if it cannot find file.c.
1276
1277 *** New option --ignore-case-regex is an alternative to --regex. It is now
1278 possible to bind a regexp to a language, by prepending the regexp with
1279 {lang}, where lang is one of the languages that `etags --help' prints out.
1280 This feature is useful especially for regex files, where each line contains
1281 a regular expression. The manual contains details.
1282
1283 *** In C and derived languages, etags creates tags for function
1284 declarations when given the --declarations option.
1285
1286 *** In C++, tags are created for "operator". The tags have the form
1287 "operator+", without spaces between the keyword and the operator.
1288
1289 *** New language Ada: tags are functions, procedures, packages, tasks, and
1290 types.
1291
1292 *** In Fortran, `procedure' is not tagged.
1293
1294 *** In Java, tags are created for "interface".
1295
1296 *** In Lisp, "(defstruct (foo", "(defun (operator" and similar constructs
1297 are now tagged.
1298
1299 *** In Perl, the --globals option tags global variables. my and local
1300 variables are tagged.
1301
1302 *** New language Python: def and class at the beginning of a line are tags.
1303
1304 *** .ss files are Scheme files, .pdb is Postscript with C syntax, .psw is
1305 for PSWrap.
1306
1307 +++
1308 ** Changes in etags.el
1309
1310 *** The new user-option tags-case-fold-search can be used to make
1311 tags operations case-sensitive or case-insensitive. The default
1312 is to use the same setting as case-fold-search.
1313
1314 *** You can display additional output with M-x tags-apropos by setting
1315 the new variable tags-apropos-additional-actions.
1316
1317 If non-nil, the variable's value should be a list of triples (TITLE
1318 FUNCTION TO-SEARCH). For each triple, M-x tags-apropos processes
1319 TO-SEARCH and lists tags from it. TO-SEARCH should be an alist,
1320 obarray, or symbol. If it is a symbol, the symbol's value is used.
1321
1322 TITLE is a string to use to label the list of tags from TO-SEARCH.
1323
1324 FUNCTION is a function to call when an entry is selected in the Tags
1325 List buffer. It is called with one argument, the selected symbol.
1326
1327 A useful example value for this variable might be something like:
1328
1329 '(("Emacs Lisp" Info-goto-emacs-command-node obarray)
1330 ("Common Lisp" common-lisp-hyperspec common-lisp-hyperspec-obarray)
1331 ("SCWM" scwm-documentation scwm-obarray))
1332
1333 *** The face tags-tag-face can be used to customize the appearance
1334 of tags in the output of M-x tags-apropos.
1335
1336 *** Setting tags-apropos-verbose to a non-nil value displays the
1337 names of tags files in the *Tags List* buffer.
1338
1339 +++
1340 ** Emacs now attempts to determine the initial language environment
1341 and preferred and locale coding systems systematically from the
1342 LC_ALL, LC_CTYPE, and LANG environment variables during startup.
1343
1344 +++
1345 ** New language environments `Polish', `Latin-8' and `Latin-9'.
1346 Latin-8 and Latin-9 correspond respectively to the ISO character sets
1347 8859-14 (Celtic) and 8859-15 (updated Latin-1, with the Euro sign).
1348 GNU Intlfonts doesn't support these yet; there are basic 8859-14 and
1349 8859-15 fonts at <URL:http://czyborra.com/charsets/> and recent X
1350 releases have 8859-15. There are new Latin-8 and Latin-9 prefix
1351 (only) and Polish slash input methods in Leim.
1352
1353 +++
1354 ** Fortran mode has a new command `fortran-strip-sequence-nos' to
1355 remove text past column 72. The syntax class of `\' in Fortran is now
1356 appropriate for C-style escape sequences in strings.
1357
1358 ** SGML mode's default `sgml-validate-command' is now `nsgmls'.
1359
1360 +++
1361 ** A new command `view-emacs-problems' (C-h P) displays the PROBLEMS file.
1362
1363 +++
1364 ** The Dabbrev package has a new user-option `dabbrev-ignored-regexps'
1365 containing a list of regular expressions. Buffers matching a regular
1366 expression from that list, are not checked.
1367
1368 ** Emacs can now figure out modification times of remote files.
1369 When you do C-x C-f /user@host:/path/file RET and edit the file,
1370 and someone else modifies the file, you will be prompted to revert
1371 the buffer, just like for the local files.
1372
1373 ** The buffer menu (C-x C-b) no longer lists the *Buffer List* buffer.
1374
1375 +++
1376 ** When invoked with a prefix argument, the command `list-abbrevs' now
1377 displays local abbrevs, only.
1378
1379 ** VC Changes
1380
1381 VC has been overhauled internally. It is now modular, making it
1382 easier to plug-in arbitrary version control backends. (See Lisp
1383 Changes for details on the new structure.) As a result, the mechanism
1384 to enable and disable support for particular version systems has
1385 changed: everything is now controlled by the new variable
1386 `vc-handled-backends'. Its value is a list of atoms that identify
1387 version systems; the default is '(RCS CVS SCCS). When finding a file,
1388 each of the backends in that list is tried in order to see whether the
1389 file is registered in that backend.
1390
1391 When registering a new file, VC first tries each of the listed
1392 backends to see if any of them considers itself "responsible" for the
1393 directory of the file (e.g. because a corresponding subdirectory for
1394 master files exists). If none of the backends is responsible, then
1395 the first backend in the list that could register the file is chosen.
1396 As a consequence, the variable `vc-default-back-end' is now obsolete.
1397
1398 The old variable `vc-master-templates' is also obsolete, although VC
1399 still supports it for backward compatibility. To define templates for
1400 RCS or SCCS, you should rather use the new variables
1401 vc-{rcs,sccs}-master-templates. (There is no such feature under CVS
1402 where it doesn't make sense.)
1403
1404 The variables `vc-ignore-vc-files' and `vc-handle-cvs' are also
1405 obsolete now, you must set `vc-handled-backends' to nil or exclude
1406 `CVS' from the list, respectively, to achieve their effect now.
1407
1408 *** General Changes
1409
1410 The variable `vc-checkout-carefully' is obsolete: the corresponding
1411 checks are always done now.
1412
1413 VC Dired buffers are now kept up-to-date during all version control
1414 operations.
1415
1416 *** Changes for CVS
1417
1418 There is a new user option, `vc-cvs-stay-local'. If it is `t' (the
1419 default), then VC avoids network queries for files registered in
1420 remote repositories. The state of such files is then only determined
1421 by heuristics and past information. `vc-cvs-stay-local' can also be a
1422 regexp to match against repository hostnames; only files from hosts
1423 that match it are treated locally. If the variable is nil, then VC
1424 queries the repository just as often as it does for local files.
1425
1426 If `vc-cvs-stay-local' is on, and there have been changes in the
1427 repository, VC notifies you about it when you actually try to commit.
1428 If you want to check for updates from the repository without trying to
1429 commit, you can either use C-u C-x v m to perform an update on the
1430 current file, or you can use C-x v r RET to get an update for an
1431 entire directory tree.
1432
1433 The new user option `vc-cvs-use-edit' indicates whether VC should call
1434 "cvs edit" to make files writeable; it defaults to `t'. (This option
1435 is only meaningful if the CVSREAD variable is set, or if files are
1436 "watched" by other developers.)
1437
1438 *** Lisp Changes in VC
1439
1440 VC has been restructured internally to make it modular. You can now
1441 add support for arbitrary version control backends by writing a
1442 library that provides a certain set of backend-specific functions, and
1443 then telling VC to use that library. For example, to add support for
1444 a version system named FOO, you write a library named vc-foo.el, which
1445 provides a number of functions vc-foo-... (see commentary at the end
1446 of vc.el for a detailed list of them). To make VC use that library,
1447 you need to put it somewhere into Emacs' load path and add the atom
1448 `FOO' to the list `vc-handled-backends'.
1449
1450 ** New modes and packages
1451
1452 +++
1453 *** The new package timeclock.el is a mode is for keeping track of time
1454 intervals. You can use it for whatever purpose you like, but the
1455 typical scenario is to keep track of how much time you spend working
1456 on certain projects.
1457
1458 +++
1459 *** The new package hi-lock.el, text matching interactively entered
1460 regexp's can be highlighted. For example,
1461
1462 M-x highlight-regexp RET clearly RET RET
1463
1464 will highlight all occurrences of `clearly' using a yellow background
1465 face. New occurrences of `clearly' will be highlighted as they are
1466 typed. `M-x unhighlight-regexp RET' will remove the highlighting.
1467 Any existing face can be used for highlighting and a set of
1468 appropriate faces is provided. The regexps can be written into the
1469 current buffer in a form that will be recognized the next time the
1470 corresponding file is read.
1471
1472 +++
1473 *** The new package zone.el plays games with Emacs' display when
1474 Emacs is idle.
1475
1476 *** The new package xml.el provides a simple but generic XML
1477 parser. It doesn't parse the DTDs however.
1478
1479 *** The comment operations are now provided by the newcomment.el
1480 package which allows different styles of comment-region and should
1481 be more robust while offering the same functionality.
1482
1483 +++
1484 *** The Ebrowse package implements a C++ class browser and tags
1485 facilities tailored for use with C++. It is documented in a
1486 separate Texinfo file.
1487
1488 +++
1489 *** The PCL-CVS package available by either running M-x cvs-examine or
1490 by visiting a CVS administrative directory (with a prefix argument)
1491 provides an alternative interface to VC-dired for CVS. It comes with
1492 `log-view-mode' to view RCS and SCCS logs and `log-edit-mode' used to
1493 enter checkin log messages.
1494
1495 +++
1496 *** The new package called `woman' allows to browse Unix man pages
1497 without invoking external programs.
1498
1499 The command `M-x woman' formats manual pages entirely in Emacs Lisp
1500 and then displays them, like `M-x manual-entry' does. Unlike
1501 `manual-entry', `woman' does not invoke any external programs, so it
1502 is useful on systems such as MS-DOS/MS-Windows where the `man' and
1503 Groff or `troff' commands are not readily available.
1504
1505 The command `M-x woman-find-file' asks for the file name of a man
1506 page, then formats and displays it like `M-x woman' does.
1507
1508 +++
1509 *** The new command M-x re-builder offers a convenient interface for
1510 authoring regular expressions with immediate visual feedback.
1511
1512 The buffer from which the command was called becomes the target for
1513 the regexp editor popping up in a separate window. Matching text in
1514 the target buffer is immediately color marked during the editing.
1515 Each sub-expression of the regexp will show up in a different face so
1516 even complex regexps can be edited and verified on target data in a
1517 single step.
1518
1519 On displays not supporting faces the matches instead blink like
1520 matching parens to make them stand out. On such a setup you will
1521 probably also want to use the sub-expression mode when the regexp
1522 contains such to get feedback about their respective limits.
1523
1524 +++
1525 *** glasses-mode is a minor mode that makes
1526 unreadableIdentifiersLikeThis readable. It works as glasses, without
1527 actually modifying content of a buffer.
1528
1529 *** The package ebnf2ps translates an EBNF to a syntactic chart in
1530 PostScript.
1531
1532 Currently accepts ad-hoc EBNF, ISO EBNF and Bison/Yacc.
1533
1534 The ad-hoc default EBNF syntax has the following elements:
1535
1536 ; comment (until end of line)
1537 A non-terminal
1538 "C" terminal
1539 ?C? special
1540 $A default non-terminal
1541 $"C" default terminal
1542 $?C? default special
1543 A = B. production (A is the header and B the body)
1544 C D sequence (C occurs before D)
1545 C | D alternative (C or D occurs)
1546 A - B exception (A excluding B, B without any non-terminal)
1547 n * A repetition (A repeats n (integer) times)
1548 (C) group (expression C is grouped together)
1549 [C] optional (C may or not occurs)
1550 C+ one or more occurrences of C
1551 {C}+ one or more occurrences of C
1552 {C}* zero or more occurrences of C
1553 {C} zero or more occurrences of C
1554 C / D equivalent to: C {D C}*
1555 {C || D}+ equivalent to: C {D C}*
1556 {C || D}* equivalent to: [C {D C}*]
1557 {C || D} equivalent to: [C {D C}*]
1558
1559 Please, see ebnf2ps documentation for EBNF syntax and how to use it.
1560
1561 *** The package align.el will align columns within a region, using M-x
1562 align. Its mode-specific rules, based on regular expressions,
1563 determine where the columns should be split. In C and C++, for
1564 example, it will align variable names in declaration lists, or the
1565 equal signs of assignments.
1566
1567 +++
1568 *** `paragraph-indent-minor-mode' is a new minor mode supporting
1569 paragraphs in the same style as `paragraph-indent-text-mode'.
1570
1571 +++
1572 *** bs.el is a new package for buffer selection similar to
1573 list-buffers or electric-buffer-list. Use M-x bs-show to display a
1574 buffer menu with this package. You can use M-x bs-customize to
1575 customize the package.
1576
1577 *** find-lisp.el is a package emulating the Unix find command in Lisp.
1578
1579 *** calculator.el is a small calculator package that is intended to
1580 replace desktop calculators such as xcalc and calc.exe. Actually, it
1581 is not too small - it has more features than most desktop calculators,
1582 and can be customized easily to get many more functions. It should
1583 not be confused with "calc" which is a much bigger mathematical tool
1584 which answers different needs.
1585
1586 +++
1587 *** The minor modes cwarn-mode and global-cwarn-mode highlights
1588 suspicious C and C++ constructions. Currently, assignments inside
1589 expressions, semicolon following `if', `for' and `while' (except, of
1590 course, after a `do .. while' statement), and C++ functions with
1591 reference parameters are recognized. The modes require font-lock mode
1592 to be enabled.
1593
1594 +++
1595 *** smerge-mode.el provides `smerge-mode', a simple minor-mode for files
1596 containing diff3-style conflict markers, such as generated by RCS.
1597
1598 +++
1599 *** 5x5.el is a simple puzzle game.
1600
1601 +++
1602 *** hl-line.el provides a minor mode to highlight the current line.
1603
1604 *** ansi-color.el translates ANSI terminal escapes into text-properties.
1605
1606 Please note: if `ansi-color-for-shell-mode' and
1607 `global-font-lock-mode' are non-nil, loading ansi-color.el will
1608 disable font-lock and add `ansi-color-apply' to
1609 `comint-preoutput-filter-functions' for all shell-mode buffers. This
1610 displays the output of "ls --color=yes" using the correct foreground
1611 and background colors.
1612
1613 *** delphi.el provides a major mode for editing the Delphi (Object
1614 Pascal) language.
1615
1616 +++
1617 *** quickurl.el provides a simple method of inserting a URL based on
1618 the text at point.
1619
1620 *** sql.el provides an interface to SQL data bases.
1621
1622 +++
1623 *** fortune.el uses the fortune program to create mail/news signatures.
1624
1625 *** whitespace.el ???
1626
1627 *** PostScript mode (ps-mode) is a new major mode for editing PostScript
1628 files. It offers: interaction with a PostScript interpreter, including
1629 (very basic) error handling; fontification, easily customizable for
1630 interpreter messages; auto-indentation; insertion of EPSF templates and
1631 often used code snippets; viewing of BoundingBox; commenting out /
1632 uncommenting regions; conversion of 8bit characters to PostScript octal
1633 codes. All functionality is accessible through a menu.
1634
1635 *** delim-col helps to prettify columns in a text region or rectangle.
1636
1637 Here is an example of columns:
1638
1639 horse apple bus
1640 dog pineapple car EXTRA
1641 porcupine strawberry airplane
1642
1643 Doing the following settings:
1644
1645 (setq delimit-columns-str-before "[ ")
1646 (setq delimit-columns-str-after " ]")
1647 (setq delimit-columns-str-separator ", ")
1648 (setq delimit-columns-separator "\t")
1649
1650
1651 Selecting the lines above and typing:
1652
1653 M-x delimit-columns-region
1654
1655 It results:
1656
1657 [ horse , apple , bus , ]
1658 [ dog , pineapple , car , EXTRA ]
1659 [ porcupine, strawberry, airplane, ]
1660
1661 delim-col has the following options:
1662
1663 delimit-columns-str-before Specify a string to be inserted
1664 before all columns.
1665
1666 delimit-columns-str-separator Specify a string to be inserted
1667 between each column.
1668
1669 delimit-columns-str-after Specify a string to be inserted
1670 after all columns.
1671
1672 delimit-columns-separator Specify a regexp which separates
1673 each column.
1674
1675 delim-col has the following commands:
1676
1677 delimit-columns-region Prettify all columns in a text region.
1678 delimit-columns-rectangle Prettify all columns in a text rectangle.
1679
1680 +++
1681 *** The package recentf.el maintains a menu for visiting files that
1682 were operated on recently.
1683
1684 M-x recentf-mode RET toggles recentf mode.
1685
1686 M-x customize-variable RET recentf-mode RET can be used to enable
1687 recentf at Emacs startup.
1688
1689 M-x customize-variable RET recentf-menu-filter RET to specify a menu
1690 filter function to change the menu appearance. For example, the recent
1691 file list can be displayed:
1692
1693 - organized by major modes, directories or user defined rules.
1694 - sorted by file pathes, file names, ascending or descending.
1695 - showing pathes relative to the current default-directory
1696
1697 The `recentf-filter-changer' menu filter function allows to
1698 dynamically change the menu appearance.
1699
1700 *** elide-head.el provides a mechanism for eliding boilerplate header
1701 text.
1702
1703 +++
1704 *** footnote.el provides `footnote-mode', a minor mode supporting use
1705 of footnotes. It is intended for use with Message mode, but isn't
1706 specific to Message mode.
1707
1708 +++
1709 *** diff-mode.el provides `diff-mode', a major mode for
1710 viewing/editing context diffs (patches). It is selected for files
1711 with extension `.diff', `.diffs', `.patch' and `.rej'.
1712
1713 +++
1714 *** EUDC, the Emacs Unified Directory Client, provides a common user
1715 interface to access directory servers using different directory
1716 protocols. It has a separate manual.
1717
1718 *** autoconf.el provides a major mode for editing configure.in files
1719 for Autoconf, selected automatically.
1720
1721 +++
1722 *** windmove.el provides moving between windows.
1723
1724 *** crm.el provides a facility to read multiple strings from the
1725 minibuffer with completion.
1726
1727 *** todo-mode.el provides management of TODO lists and integration
1728 with the diary features.
1729
1730 *** autoarg.el provides a feature reported from Twenex Emacs whereby
1731 numeric keys supply prefix args rather than self inserting.
1732
1733 *** The function `turn-off-auto-fill' unconditionally turns off Auto
1734 Fill mode.
1735
1736 *** gnus-mule.el is now just a compatibility layer over the built-in
1737 Gnus facilities.
1738
1739 ** Withdrawn packages
1740
1741 *** mldrag.el has been removed. mouse.el provides the same
1742 functionality with aliases for the mldrag functions.
1743
1744 *** eval-reg.el has been obsoleted by changes to edebug.el and removed.
1745
1746 *** ph.el has been obsoleted by EUDC and removed.
1747
1748 \f
1749 * Lisp changes made after edition 2.6 of the Emacs Lisp Manual,
1750 (Display-related features are described in a page of their own below.)
1751
1752 +++
1753 ** The new function `display-message-or-buffer' displays a message in
1754 the echo area or pops up a buffer, depending on the length of the
1755 message.
1756
1757 ** The new macro `with-auto-compression-mode' allows evaluating an
1758 expression with auto-compression-mode enabled.
1759
1760 ** In image specifications, `:heuristic-mask' has been replaced
1761 with the more general `:mask' property.
1762
1763 ** Image specifications accept more `:algorithm's.
1764
1765 ** A `?' can be used in a symbol name without escaping it with a
1766 backslash.
1767
1768 +++
1769 ** Reading from the mini-buffer now reads from standard input if Emacs
1770 is running in batch mode. For example,
1771
1772 (message "%s" (read t))
1773
1774 will read a Lisp expression from standard input and print the result
1775 to standard output.
1776
1777 +++
1778 ** The argument of `down-list', `backward-up-list', `up-list',
1779 `kill-sexp', `backward-kill-sexp' and `mark-sexp' is now optional.
1780
1781 ** If `display-buffer-reuse-frames' is set, function `display-buffer'
1782 will raise frames displaying a buffer, instead of creating a new
1783 frame or window.
1784
1785 +++
1786 ** Two new functions for removing elements from lists/sequences
1787 were added
1788
1789 - Function: remove ELT SEQ
1790
1791 Return a copy of SEQ with all occurences of ELT removed. SEQ must be
1792 a list, vector, or string. The comparison is done with `equal'.
1793
1794 - Function: remq ELT LIST
1795
1796 Return a copy of LIST with all occurences of ELT removed. The
1797 comparison is done with `eq'.
1798
1799 ** The function `delete' now also works with vectors and strings.
1800
1801 ** The meaning of the `:weakness WEAK' argument of make-hash-table
1802 has been changed.
1803
1804 +++
1805 ** Function `aset' stores any multibyte character in any string
1806 without signaling "Attempt to change char length of a string". It may
1807 convert a unibyte string to multibyte if necessary.
1808
1809 ** The value of the `help-echo' text property is called as a function
1810 or evaluated, if it is not a string already, to obtain a help string.
1811
1812 ** Function `make-obsolete' now has an optional arg to say when the
1813 function was declared obsolete.
1814
1815 ** Function `plist-member' is renamed from `widget-plist-member' (which is
1816 retained as an alias).
1817
1818 ** Easy-menu's :filter now works as in XEmacs.
1819 It takes the unconverted (i.e. XEmacs) form of the menu and the result
1820 is automatically converted to Emacs' form.
1821
1822 ** The new function `window-list' has been defined
1823
1824 - Function: window-list &optional WINDOW MINIBUF ALL-FRAMES
1825
1826 Return a list of windows in canonical order. The parameters WINDOW,
1827 MINIBUF and ALL-FRAMES are defined like for `next-window'.
1828
1829 ** There's a new function `some-window' defined as follows
1830
1831 - Function: some-window PREDICATE &optional MINIBUF ALL-FRAMES DEFAULT
1832
1833 Return a window satisfying PREDICATE.
1834
1835 This function cycles through all visible windows using `walk-windows',
1836 calling PREDICATE on each one. PREDICATE is called with a window as
1837 argument. The first window for which PREDICATE returns a non-nil
1838 value is returned. If no window satisfies PREDICATE, DEFAULT is
1839 returned.
1840
1841 Optional second arg MINIBUF t means count the minibuffer window even
1842 if not active. MINIBUF nil or omitted means count the minibuffer iff
1843 it is active. MINIBUF neither t nor nil means not to count the
1844 minibuffer even if it is active.
1845
1846 Several frames may share a single minibuffer; if the minibuffer
1847 counts, all windows on all frames that share that minibuffer count
1848 too. Therefore, if you are using a separate minibuffer frame
1849 and the minibuffer is active and MINIBUF says it counts,
1850 `walk-windows' includes the windows in the frame from which you
1851 entered the minibuffer, as well as the minibuffer window.
1852
1853 ALL-FRAMES is the optional third argument.
1854 ALL-FRAMES nil or omitted means cycle within the frames as specified above.
1855 ALL-FRAMES = `visible' means include windows on all visible frames.
1856 ALL-FRAMES = 0 means include windows on all visible and iconified frames.
1857 ALL-FRAMES = t means include windows on all frames including invisible frames.
1858 If ALL-FRAMES is a frame, it means include windows on that frame.
1859 Anything else means restrict to the selected frame.
1860
1861 ** The function `single-key-description' now encloses function key and
1862 event names in angle brackets. When called with a second optional
1863 argument non-nil, angle brackets won't be printed.
1864
1865 ** If the variable `message-truncate-lines' is bound to t around a
1866 call to `message', the echo area will not be resized to display that
1867 message; it will be truncated instead, as it was done in 20.x.
1868 Default value is nil.
1869
1870 ** The user option `line-number-display-limit' can now be set to nil,
1871 meaning no limit.
1872
1873 ** `select-safe-coding-system' now also checks the most preferred
1874 coding-system if buffer-file-coding-system is `undecided' and
1875 DEFAULT-CODING-SYSTEM is not specified,
1876
1877 ** The function `subr-arity' provides information on the argument list
1878 of a primitive.
1879
1880 ** The text property `keymap' specifies a key map which overrides the
1881 buffer's local map and the map specified by the `local-map' property.
1882 This is probably what most current uses of `local-map' want, rather
1883 than replacing the local map.
1884
1885 ** The obsolete variables before-change-function and
1886 after-change-function are no longer acted upon and have been removed.
1887
1888 ** The function `apropos-mode' runs the hook `apropos-mode-hook'.
1889
1890 +++
1891 ** `concat' no longer accepts individual integer arguments, as
1892 promised long ago.
1893
1894 ** The new function `float-time' returns the current time as a float.
1895 \f
1896 * Lisp changes in Emacs 21.1 (see following page for display-related features)
1897
1898 Note that +++ before an item means the Lisp manual has been updated.
1899 --- means that I have decided it does not need to be in the Lisp manual.
1900 When you add a new item, please add it without either +++ or ---
1901 so I will know I still need to look at it -- rms.
1902
1903 *** The special form `save-restriction' now works correctly even if the
1904 buffer is widened inside the save-restriction and changes made outside
1905 the original restriction. Previously, doing this would cause the saved
1906 restriction to be restored incorrectly.
1907
1908 *** The functions `find-charset-region' and `find-charset-string' include
1909 `eight-bit-control' and/or `eight-bit-graphic' in the returned list
1910 when it finds 8-bit characters. Previously, it included `ascii' in a
1911 multibyte buffer and `unknown' in a unibyte buffer.
1912
1913 *** The functions `set-buffer-modified', `string-as-multibyte' and
1914 `string-as-unibyte' change the byte sequence of a buffer if it
1915 contains a character from the `eight-bit-control' character set.
1916
1917 *** The handling of multibyte sequences in a multibyte buffer is
1918 changed. Previously, a byte sequence matching the pattern
1919 [\200-\237][\240-\377]+ was interpreted as a single character
1920 regardless of the length of the trailing bytes [\240-\377]+. Thus, if
1921 the sequence was longer than what the leading byte indicated, the
1922 extra trailing bytes were ignored by Lisp functions. Now such extra
1923 bytes are independent 8-bit characters belonging to the charset
1924 eight-bit-graphic.
1925
1926 ** Fontsets are now implemented using char-tables.
1927
1928 A fontset can now be specified for for each independent character, for
1929 a group of characters or for a character set rather than just for a
1930 character set as previously.
1931
1932 *** The arguments of the function `set-fontset-font' are changed.
1933 They are NAME, CHARACTER, FONTNAME, and optional FRAME. The function
1934 modifies fontset NAME to use FONTNAME for CHARACTER.
1935
1936 CHARACTER may be a cons (FROM . TO), where FROM and TO are non-generic
1937 characters. In that case FONTNAME is used for all characters in the
1938 range FROM and TO (inclusive). CHARACTER may be a charset. In that
1939 case FONTNAME is used for all character in the charset.
1940
1941 FONTNAME may be a cons (FAMILY . REGISTRY), where FAMILY is the family
1942 name of a font and REGSITRY is a registry name of a font.
1943
1944 *** Variable x-charset-registry has been deleted. The default charset
1945 registries of character sets are set in the default fontset
1946 "fontset-default".
1947
1948 *** The function `create-fontset-from-fontset-spec' ignores the second
1949 argument STYLE-VARIANT. It never creates style-variant fontsets.
1950
1951 ** The method of composing characters is changed. Now character
1952 composition is done by a special text property `composition' in
1953 buffers and strings.
1954
1955 *** Charset composition is deleted. Emacs never creates a `composite
1956 character' which is an independent character with a unique character
1957 code. Thus the following functions handling `composite characters'
1958 have been deleted: composite-char-component,
1959 composite-char-component-count, composite-char-composition-rule,
1960 composite-char-composition-rule and decompose-composite-char delete.
1961 The variables leading-code-composition and min-composite-char have
1962 also been deleted.
1963
1964 *** Three more glyph reference points are added. They can be used to
1965 specify a composition rule. See the documentation of the variable
1966 `reference-point-alist' for more detail.
1967
1968 *** The function `compose-region' takes new arguments COMPONENTS and
1969 MODIFICATION-FUNC. With COMPONENTS, you can specify not only a
1970 composition rule but also characters to be composed. Such characters
1971 may differ between buffer and string text.
1972
1973 *** The function `compose-string' takes new arguments START, END,
1974 COMPONENTS, and MODIFICATION-FUNC.
1975
1976 *** The function `compose-string' puts text property `composition'
1977 directly on the argument STRING instead of returning a new string.
1978 Likewise, the function `decompose-string' just removes text property
1979 `composition' from STRING.
1980
1981 *** The new function `find-composition' returns information about
1982 a composition at a specified position in a buffer or a string.
1983
1984 *** The function `decompose-composite-char' is now labeled as
1985 obsolete.
1986
1987 ** The new character set `mule-unicode-0100-24ff' is introduced for
1988 Unicode characters of the range U+0100..U+24FF. Currently, this
1989 character set is not used.
1990
1991 ** The new character sets `japanese-jisx0213-1' and
1992 `japanese-jisx0213-2' are introduced for the new Japanese standard JIS
1993 X 0213 Plane 1 and Plane 2.
1994
1995 +++
1996 ** The new character sets `eight-bit-control' and `eight-bit-graphic'
1997 are introduced for 8-bit characters in the ranges 0x80..0x9F and
1998 0xA0..0xFF respectively.
1999
2000 +++
2001 ** If the APPEND argument of `write-region' is an integer, it seeks to
2002 that offset in the file before writing.
2003
2004 ** The function `add-minor-mode' has been added for convenience and
2005 compatibility with XEmacs (and is used internally by define-minor-mode).
2006
2007 ** The function `shell-command' now sets the default directory of the
2008 `*Shell Command Output*' buffer to the default directory of the buffer
2009 from which the command was issued.
2010
2011 ** The functions `query-replace', `query-replace-regexp',
2012 `query-replace-regexp-eval' `map-query-replace-regexp',
2013 `replace-string', `replace-regexp', and `perform-replace' take two
2014 additional optional arguments START and END that specify the region to
2015 operate on.
2016
2017 ** The new function `count-screen-lines' is a more flexible alternative
2018 to `window-buffer-height'.
2019
2020 - Function: count-screen-lines &optional BEG END COUNT-FINAL-NEWLINE WINDOW
2021
2022 Return the number of screen lines in the region between BEG and END.
2023 The number of screen lines may be different from the number of actual
2024 lines, due to line breaking, display table, etc.
2025
2026 Optional arguments BEG and END default to `point-min' and `point-max'
2027 respectively.
2028
2029 If region ends with a newline, ignore it unless optinal third argument
2030 COUNT-FINAL-NEWLINE is non-nil.
2031
2032 The optional fourth argument WINDOW specifies the window used for
2033 obtaining parameters such as width, horizontal scrolling, and so
2034 on. The default is to use the selected window's parameters.
2035
2036 Like `vertical-motion', `count-screen-lines' always uses the current
2037 buffer, regardless of which buffer is displayed in WINDOW. This makes
2038 possible to use `count-screen-lines' in any buffer, whether or not it
2039 is currently displayed in some window.
2040
2041 ** The new function `mapc' is like `mapcar' but doesn't collect the
2042 argument function's results.
2043
2044 ** The functions base64-decode-region and base64-decode-string now
2045 signal an error instead of returning nil if decoding fails.
2046
2047 ** The function sendmail-user-agent-compose now recognizes a `body'
2048 header in the list of headers passed to it.
2049
2050 ** The new function member-ignore-case works like `member', but
2051 ignores differences in case and text representation.
2052
2053 ** The buffer-local variable cursor-type can be used to specify the
2054 cursor to use in windows displaying a buffer. Values are interpreted
2055 as follows:
2056
2057 t use the cursor specified for the frame (default)
2058 nil don't display a cursor
2059 `bar' display a bar cursor with default width
2060 (bar . WIDTH) display a bar cursor with width WIDTH
2061 others display a box cursor.
2062
2063 ** The variable open-paren-in-column-0-is-defun-start controls whether
2064 an open parenthesis in column 0 is considered to be the start of a
2065 defun. If set, the default, it is considered a defun start. If not
2066 set, an open parenthesis in column 0 has no special meaning.
2067
2068 ** The new function `string-to-syntax' can be used to translate syntax
2069 specifications in string form as accepted by `modify-syntax-entry' to
2070 the cons-cell form that is used for the values of the `syntax-table'
2071 text property, and in `font-lock-syntactic-keywords'.
2072
2073 Example:
2074
2075 (string-to-syntax "()")
2076 => (4 . 41)
2077
2078 ** Emacs' reader supports CL read syntax for integers in bases
2079 other than 10.
2080
2081 *** `#BINTEGER' or `#bINTEGER' reads INTEGER in binary (radix 2).
2082 INTEGER optionally contains a sign.
2083
2084 #b1111
2085 => 15
2086 #b-1111
2087 => -15
2088
2089 *** `#OINTEGER' or `#oINTEGER' reads INTEGER in octal (radix 8).
2090
2091 #o666
2092 => 438
2093
2094 *** `#XINTEGER' or `#xINTEGER' reads INTEGER in hexadecimal (radix 16).
2095
2096 #xbeef
2097 => 48815
2098
2099 *** `#RADIXrINTEGER' reads INTEGER in radix RADIX, 2 <= RADIX <= 36.
2100
2101 #2R-111
2102 => -7
2103 #25rah
2104 => 267
2105
2106 ** The function `documentation-property' now evaluates the value of
2107 the given property to obtain a string if it doesn't refer to etc/DOC
2108 and isn't a string.
2109
2110 ** If called for a symbol, the function `documentation' now looks for
2111 a `function-documentation' property of that symbol. If it has a non-nil
2112 value, the documentation is taken from that value. If the value is
2113 not a string, it is evaluated to obtain a string.
2114
2115 +++
2116 ** The last argument of `define-key-after' defaults to t for convenience.
2117
2118 ** The new function `replace-regexp-in-string' replaces all matches
2119 for a regexp in a string.
2120
2121 ** `mouse-position' now runs the abnormal hook
2122 `mouse-position-function'.
2123
2124 ** The function string-to-number now returns a float for numbers
2125 that don't fit into a Lisp integer.
2126
2127 ** The variable keyword-symbols-constants-flag has been removed.
2128 Keywords are now always considered constants.
2129
2130 +++
2131 ** The new function `delete-and-extract-region' deletes text and
2132 returns it.
2133
2134 ** The function `clear-this-command-keys' now also clears the vector
2135 returned by function `recent-keys'.
2136
2137 +++
2138 ** Variables `beginning-of-defun-function' and `end-of-defun-function'
2139 can be used to define handlers for the functions that find defuns.
2140 Major modes can define these locally instead of rebinding M-C-a
2141 etc. if the normal conventions for defuns are not appropriate for the
2142 mode.
2143
2144 +++
2145 ** easy-mmode-define-minor-mode now takes an additional BODY argument
2146 and is renamed `define-minor-mode'.
2147
2148 +++
2149 ** If an abbrev has a hook function which is a symbol, and that symbol
2150 has a non-nil `no-self-insert' property, the return value of the hook
2151 function specifies whether an expansion has been done or not. If it
2152 returns nil, abbrev-expand also returns nil, meaning "no expansion has
2153 been performed."
2154
2155 When abbrev expansion is done by typing a self-inserting character,
2156 and the abbrev has a hook with the `no-self-insert' property, and the
2157 hook function returns non-nil meaning expansion has been done,
2158 then the self-inserting character is not inserted.
2159
2160 +++
2161 ** The function `intern-soft' now accepts a symbol as first argument.
2162 In this case, that exact symbol is looked up in the specified obarray,
2163 and the function's value is nil if it is not found.
2164
2165 +++
2166 ** The new macro `with-syntax-table' can be used to evaluate forms
2167 with the syntax table of the current buffer temporarily set to a
2168 specified table.
2169
2170 (with-syntax-table TABLE &rest BODY)
2171
2172 Evaluate BODY with syntax table of current buffer set to a copy of
2173 TABLE. The current syntax table is saved, BODY is evaluated, and the
2174 saved table is restored, even in case of an abnormal exit. Value is
2175 what BODY returns.
2176
2177 +++
2178 ** Regular expressions now support intervals \{n,m\} as well as
2179 Perl's shy-groups \(?:...\) and non-greedy *? +? and ?? operators.
2180
2181 +++
2182 ** The optional argument BUFFER of function file-local-copy has been
2183 removed since it wasn't used by anything.
2184
2185 +++
2186 ** The file name argument of function `file-locked-p' is now required
2187 instead of being optional.
2188
2189 +++
2190 ** The new built-in error `text-read-only' is signaled when trying to
2191 modify read-only text.
2192
2193 +++
2194 ** New functions and variables for locales.
2195
2196 The new variable `locale-coding-system' specifies how to encode and
2197 decode strings passed to low-level message functions like strerror and
2198 time functions like strftime. The new variables
2199 `system-messages-locale' and `system-time-locale' give the system
2200 locales to be used when invoking these two types of functions.
2201
2202 The new function `set-locale-environment' sets the language
2203 environment, preferred coding system, and locale coding system from
2204 the system locale as specified by the LC_ALL, LC_CTYPE, and LANG
2205 environment variables. Normally, it is invoked during startup and need
2206 not be invoked thereafter. It uses the new variables
2207 `locale-language-names', `locale-charset-language-names', and
2208 `locale-preferred-coding-systems' to make its decisions.
2209
2210 +++
2211 ** syntax tables now understand nested comments.
2212 To declare a comment syntax as allowing nesting, just add an `n'
2213 modifier to either of the characters of the comment end and the comment
2214 start sequences.
2215
2216 +++
2217 ** The function `pixmap-spec-p' has been renamed `bitmap-spec-p'
2218 because `bitmap' is more in line with the usual X terminology.
2219
2220 +++
2221 ** New function `propertize'
2222
2223 The new function `propertize' can be used to conveniently construct
2224 strings with text properties.
2225
2226 - Function: propertize STRING &rest PROPERTIES
2227
2228 Value is a copy of STRING with text properties assigned as specified
2229 by PROPERTIES. PROPERTIES is a sequence of pairs PROPERTY VALUE, with
2230 PROPERTY being the name of a text property and VALUE being the
2231 specified value of that property. Example:
2232
2233 (propertize "foo" 'face 'bold 'read-only t)
2234
2235 +++
2236 ** push and pop macros.
2237
2238 Simple versions of the push and pop macros of Common Lisp
2239 are now defined in Emacs Lisp. These macros allow only symbols
2240 as the place that holds the list to be changed.
2241
2242 (push NEWELT LISTNAME) add NEWELT to the front of LISTNAME's value.
2243 (pop LISTNAME) return first elt of LISTNAME, and remove it
2244 (thus altering the value of LISTNAME).
2245
2246 ** New dolist and dotimes macros.
2247
2248 Simple versions of the dolist and dotimes macros of Common Lisp
2249 are now defined in Emacs Lisp.
2250
2251 (dolist (VAR LIST [RESULT]) BODY...)
2252 Execute body once for each element of LIST,
2253 using the variable VAR to hold the current element.
2254 Then return the value of RESULT, or nil if RESULT is omitted.
2255
2256 (dotimes (VAR COUNT [RESULT]) BODY...)
2257 Execute BODY with VAR bound to successive integers running from 0,
2258 inclusive, to COUNT, exclusive.
2259 Then return the value of RESULT, or nil if RESULT is omitted.
2260
2261 +++
2262 ** Regular expressions now support Posix character classes such
2263 as [:alpha:], [:space:] and so on.
2264
2265 [:digit:] matches 0 through 9
2266 [:cntrl:] matches ASCII control characters
2267 [:xdigit:] matches 0 through 9, a through f and A through F.
2268 [:blank:] matches space and tab only
2269 [:graph:] matches graphic characters--everything except ASCII control chars,
2270 space, and DEL.
2271 [:print:] matches printing characters--everything except ASCII control chars
2272 and DEL.
2273 [:alnum:] matches letters and digits.
2274 (But at present, for multibyte characters,
2275 it matches anything that has word syntax.)
2276 [:alpha:] matches letters.
2277 (But at present, for multibyte characters,
2278 it matches anything that has word syntax.)
2279 [:ascii:] matches ASCII (unibyte) characters.
2280 [:nonascii:] matches non-ASCII (multibyte) characters.
2281 [:lower:] matches anything lower-case.
2282 [:punct:] matches punctuation.
2283 (But at present, for multibyte characters,
2284 it matches anything that has non-word syntax.)
2285 [:space:] matches anything that has whitespace syntax.
2286 [:upper:] matches anything upper-case.
2287 [:word:] matches anything that has word syntax.
2288
2289 +++
2290 ** Emacs now has built-in hash tables.
2291
2292 The following functions are defined for hash tables:
2293
2294 - Function: make-hash-table ARGS
2295
2296 The argument list ARGS consists of keyword/argument pairs. All arguments
2297 are optional. The following arguments are defined:
2298
2299 :test TEST
2300
2301 TEST must be a symbol specifying how to compare keys. Default is `eql'.
2302 Predefined are `eq', `eql' and `equal'. If TEST is not predefined,
2303 it must have been defined with `define-hash-table-test'.
2304
2305 :size SIZE
2306
2307 SIZE must be an integer > 0 giving a hint to the implementation how
2308 many elements will be put in the hash table. Default size is 65.
2309
2310 :rehash-size REHASH-SIZE
2311
2312 REHASH-SIZE specifies by how much to grow a hash table once it becomes
2313 full. If REHASH-SIZE is an integer, add that to the hash table's old
2314 size to get the new size. Otherwise, REHASH-SIZE must be a float >
2315 1.0, and the new size is computed by multiplying REHASH-SIZE with the
2316 old size. Default rehash size is 1.5.
2317
2318 :rehash-threshold THRESHOLD
2319
2320 THRESHOLD must be a float > 0 and <= 1.0 specifying when to resize the
2321 hash table. It is resized when the ratio of (number of entries) /
2322 (size of hash table) is >= THRESHOLD. Default threshold is 0.8.
2323
2324 :weakness WEAK
2325
2326 WEAK must be either nil, one of the symbols `key, `value',
2327 `key-or-value', `key-and-value', or t, meaning the same as
2328 `key-and-value'. Entries are removed from weak tables during garbage
2329 collection if their key and/or value are not referenced elsewhere
2330 outside of the hash table. Default are non-weak hash tables.
2331
2332 - Function: makehash &optional TEST
2333
2334 Similar to make-hash-table, but only TEST can be specified.
2335
2336 - Function: hash-table-p TABLE
2337
2338 Returns non-nil if TABLE is a hash table object.
2339
2340 - Function: copy-hash-table TABLE
2341
2342 Returns a copy of TABLE. Only the table itself is copied, keys and
2343 values are shared.
2344
2345 - Function: hash-table-count TABLE
2346
2347 Returns the number of entries in TABLE.
2348
2349 - Function: hash-table-rehash-size TABLE
2350
2351 Returns the rehash size of TABLE.
2352
2353 - Function: hash-table-rehash-threshold TABLE
2354
2355 Returns the rehash threshold of TABLE.
2356
2357 - Function: hash-table-rehash-size TABLE
2358
2359 Returns the size of TABLE.
2360
2361 - Function: hash-table-test TABLE
2362
2363 Returns the test TABLE uses to compare keys.
2364
2365 - Function: hash-table-weakness TABLE
2366
2367 Returns the weakness specified for TABLE.
2368
2369 - Function: clrhash TABLE
2370
2371 Clear TABLE.
2372
2373 - Function: gethash KEY TABLE &optional DEFAULT
2374
2375 Look up KEY in TABLE and return its associated VALUE or DEFAULT if
2376 not found.
2377
2378 - Function: puthash KEY VALUE TABLE
2379
2380 Associate KEY with VALUE in TABLE. If KEY is already associated with
2381 another value, replace the old value with VALUE.
2382
2383 - Function: remhash KEY TABLE
2384
2385 Remove KEY from TABLE if it is there.
2386
2387 - Function: maphash FUNCTION TABLE
2388
2389 Call FUNCTION for all elements in TABLE. FUNCTION must take two
2390 arguments KEY and VALUE.
2391
2392 - Function: sxhash OBJ
2393
2394 Return a hash code for Lisp object OBJ.
2395
2396 - Function: define-hash-table-test NAME TEST-FN HASH-FN
2397
2398 Define a new hash table test named NAME. If NAME is specified as
2399 a test in `make-hash-table', the table created will use TEST-FN for
2400 comparing keys, and HASH-FN to compute hash codes for keys. Test
2401 and hash function are stored as symbol property `hash-table-test'
2402 of NAME with a value of (TEST-FN HASH-FN).
2403
2404 TEST-FN must take two arguments and return non-nil if they are the same.
2405
2406 HASH-FN must take one argument and return an integer that is the hash
2407 code of the argument. The function should use the whole range of
2408 integer values for hash code computation, including negative integers.
2409
2410 Example: The following creates a hash table whose keys are supposed to
2411 be strings that are compared case-insensitively.
2412
2413 (defun case-fold-string= (a b)
2414 (compare-strings a nil nil b nil nil t))
2415
2416 (defun case-fold-string-hash (a)
2417 (sxhash (upcase a)))
2418
2419 (define-hash-table-test 'case-fold 'case-fold-string=
2420 'case-fold-string-hash))
2421
2422 (make-hash-table :test 'case-fold)
2423
2424 +++
2425 ** The Lisp reader handles circular structure.
2426
2427 It now works to use the #N= and #N# constructs to represent
2428 circular structures. For example, #1=(a . #1#) represents
2429 a cons cell which is its own cdr.
2430
2431 +++
2432 ** The Lisp printer handles circular structure.
2433
2434 If you bind print-circle to a non-nil value, the Lisp printer outputs
2435 #N= and #N# constructs to represent circular and shared structure.
2436
2437 +++
2438 ** If the second argument to `move-to-column' is anything but nil or
2439 t, that means replace a tab with spaces if necessary to reach the
2440 specified column, but do not add spaces at the end of the line if it
2441 is too short to reach that column.
2442
2443 +++
2444 ** perform-replace has a new feature: the REPLACEMENTS argument may
2445 now be a cons cell (FUNCTION . DATA). This means to call FUNCTION
2446 after each match to get the replacement text. FUNCTION is called with
2447 two arguments: DATA, and the number of replacements already made.
2448
2449 If the FROM-STRING contains any upper-case letters,
2450 perform-replace also turns off `case-fold-search' temporarily
2451 and inserts the replacement text without altering case in it.
2452
2453 +++
2454 ** The function buffer-size now accepts an optional argument
2455 to specify which buffer to return the size of.
2456
2457 +++
2458 ** The calendar motion commands now run the normal hook
2459 calendar-move-hook after moving point.
2460
2461 +++
2462 ** The new variable small-temporary-file-directory specifies a
2463 directory to use for creating temporary files that are likely to be
2464 small. (Certain Emacs features use this directory.) If
2465 small-temporary-file-directory is nil, they use
2466 temporary-file-directory instead.
2467
2468 +++
2469 ** The variable `inhibit-modification-hooks', if non-nil, inhibits all
2470 the hooks that track changes in the buffer. This affects
2471 `before-change-functions' and `after-change-functions', as well as
2472 hooks attached to text properties and overlay properties.
2473
2474 +++
2475 ** assoc-delete-all is a new function that deletes all the
2476 elements of an alist which have a particular value as the car.
2477
2478 +++
2479 ** make-temp-file provides a more reliable way to create a temporary file.
2480
2481 make-temp-file is used like make-temp-name, except that it actually
2482 creates the file before it returns. This prevents a timing error,
2483 ensuring that no other job can use the same name for a temporary file.
2484
2485 +++
2486 ** New exclusive-open feature in `write-region'
2487
2488 The optional seventh arg is now called MUSTBENEW. If non-nil, it insists
2489 on a check for an existing file with the same name. If MUSTBENEW
2490 is `excl', that means to get an error if the file already exists;
2491 never overwrite. If MUSTBENEW is neither nil nor `excl', that means
2492 ask for confirmation before overwriting, but do go ahead and
2493 overwrite the file if the user gives confirmation.
2494
2495 If the MUSTBENEW argument in `write-region' is `excl',
2496 that means to use a special feature in the `open' system call
2497 to get an error if the file exists at that time.
2498 The error reported is `file-already-exists'.
2499
2500 +++
2501 ** Function `format' now handles text properties.
2502
2503 Text properties of the format string are applied to the result string.
2504 If the result string is longer than the format string, text properties
2505 ending at the end of the format string are extended to the end of the
2506 result string.
2507
2508 Text properties from string arguments are applied to the result
2509 string where arguments appear in the result string.
2510
2511 Example:
2512
2513 (let ((s1 "hello, %s")
2514 (s2 "world"))
2515 (put-text-property 0 (length s1) 'face 'bold s1)
2516 (put-text-property 0 (length s2) 'face 'italic s2)
2517 (format s1 s2))
2518
2519 results in a bold-face string with an italic `world' at the end.
2520
2521 +++
2522 ** Messages can now be displayed with text properties.
2523
2524 Text properties are handled as described above for function `format'.
2525 The following example displays a bold-face message with an italic
2526 argument in it.
2527
2528 (let ((msg "hello, %s!")
2529 (arg "world"))
2530 (put-text-property 0 (length msg) 'face 'bold msg)
2531 (put-text-property 0 (length arg) 'face 'italic arg)
2532 (message msg arg))
2533
2534 +++
2535 ** Sound support
2536
2537 Emacs supports playing sound files on GNU/Linux and the free BSDs
2538 (Voxware driver and native BSD driver, aka as Luigi's driver).
2539
2540 Currently supported file formats are RIFF-WAVE (*.wav) and Sun Audio
2541 (*.au). You must configure Emacs with the option `--with-sound=yes'
2542 to enable sound support.
2543
2544 Sound files can be played by calling (play-sound SOUND). SOUND is a
2545 list of the form `(sound PROPERTY...)'. The function is only defined
2546 when sound support is present for the system on which Emacs runs. The
2547 functions runs `play-sound-functions' with one argument which is the
2548 sound to play, before playing the sound.
2549
2550 The following sound properties are supported:
2551
2552 - `:file FILE'
2553
2554 FILE is a file name. If FILE isn't an absolute name, it will be
2555 searched relative to `data-directory'.
2556
2557 - `:data DATA'
2558
2559 DATA is a string containing sound data. Either :file or :data
2560 may be present, but not both.
2561
2562 - `:volume VOLUME'
2563
2564 VOLUME must be an integer in the range 0..100 or a float in the range
2565 0..1. This property is optional.
2566
2567 Other properties are ignored.
2568
2569 ** `multimedia' is a new Finder keyword and Custom group.
2570
2571 ** keywordp is a new predicate to test efficiently for an object being
2572 a keyword symbol.
2573
2574 ** Changes to garbage collection
2575
2576 *** The function garbage-collect now additionally returns the number
2577 of live and free strings.
2578
2579 *** There is a new variable `strings-consed' holding the number of
2580 strings that have been consed so far.
2581
2582 \f
2583 * Lisp-level Display features added after release 2.6 of the Emacs
2584 Lisp Manual
2585
2586 *** On window systems, `glyph-table' is no longer used.
2587
2588 +++
2589 ** Help strings in menu items are now used to provide `help-echo' text.
2590
2591 ** The function `image-size' can be used to determine the size of an
2592 image.
2593
2594 - Function: image-size SPEC &optional PIXELS FRAME
2595
2596 Return the size of an image as a pair (WIDTH . HEIGHT).
2597
2598 SPEC is an image specification. PIXELS non-nil means return sizes
2599 measured in pixels, otherwise return sizes measured in canonical
2600 character units (fractions of the width/height of the frame's default
2601 font). FRAME is the frame on which the image will be displayed.
2602 FRAME nil or omitted means use the selected frame.
2603
2604 ** The function `image-mask-p' can be used to determine if an image
2605 has a mask bitmap.
2606
2607 - Function: image-mask-p SPEC &optional FRAME
2608
2609 Return t if image SPEC has a mask bitmap.
2610 FRAME is the frame on which the image will be displayed. FRAME nil
2611 or omitted means use the selected frame.
2612
2613 +++
2614 ** The function `find-image' can be used to find a usable image
2615 satisfying one of a list of specifications.
2616
2617 +++
2618 ** The STRING argument of `put-image' and `insert-image' is now
2619 optional.
2620
2621 +++
2622 ** Image specifications may contain the property `:ascent center' (see
2623 below).
2624
2625 \f
2626 * New Lisp-level Display features in Emacs 21.1
2627
2628 Note that +++ before an item means the Lisp manual has been updated.
2629 --- means that I have decided it does not need to be in the Lisp manual.
2630 When you add a new item, please add it without either +++ or ---
2631 so I will know I still need to look at it -- rms.
2632
2633 ** The function tty-suppress-bold-inverse-default-colors can be used
2634 to make Emacs avoid displaying text with bold black foreground on TTYs.
2635
2636 Some terminals, notably PC consoles, emulate bold text by displaying
2637 text in brighter colors. On such a console, a bold black foreground
2638 is displayed in a gray color. If this turns out to be hard to read on
2639 your monitor---the problem occurred with the mode line on
2640 laptops---you can instruct Emacs to ignore the text's boldness, and to
2641 just display it black instead.
2642
2643 This situation can't be detected automatically. You will have to put
2644 a line like
2645
2646 (tty-suppress-bold-inverse-default-colors t)
2647
2648 in your `.emacs'.
2649
2650 ** New face implementation.
2651
2652 Emacs faces have been reimplemented from scratch. They don't use XLFD
2653 font names anymore and face merging now works as expected.
2654
2655 +++
2656 *** New faces.
2657
2658 Each face can specify the following display attributes:
2659
2660 1. Font family or fontset alias name.
2661
2662 2. Relative proportionate width, aka character set width or set
2663 width (swidth), e.g. `semi-compressed'.
2664
2665 3. Font height in 1/10pt
2666
2667 4. Font weight, e.g. `bold'.
2668
2669 5. Font slant, e.g. `italic'.
2670
2671 6. Foreground color.
2672
2673 7. Background color.
2674
2675 8. Whether or not characters should be underlined, and in what color.
2676
2677 9. Whether or not characters should be displayed in inverse video.
2678
2679 10. A background stipple, a bitmap.
2680
2681 11. Whether or not characters should be overlined, and in what color.
2682
2683 12. Whether or not characters should be strike-through, and in what
2684 color.
2685
2686 13. Whether or not a box should be drawn around characters, its
2687 color, the width of the box lines, and 3D appearance.
2688
2689 Faces are frame-local by nature because Emacs allows to define the
2690 same named face (face names are symbols) differently for different
2691 frames. Each frame has an alist of face definitions for all named
2692 faces. The value of a named face in such an alist is a Lisp vector
2693 with the symbol `face' in slot 0, and a slot for each each of the face
2694 attributes mentioned above.
2695
2696 There is also a global face alist `face-new-frame-defaults'. Face
2697 definitions from this list are used to initialize faces of newly
2698 created frames.
2699
2700 A face doesn't have to specify all attributes. Those not specified
2701 have a nil value. Faces specifying all attributes are called
2702 `fully-specified'.
2703
2704 +++
2705 *** Face merging.
2706
2707 The display style of a given character in the text is determined by
2708 combining several faces. This process is called `face merging'. Any
2709 aspect of the display style that isn't specified by overlays or text
2710 properties is taken from the `default' face. Since it is made sure
2711 that the default face is always fully-specified, face merging always
2712 results in a fully-specified face.
2713
2714 +++
2715 *** Face realization.
2716
2717 After all face attributes for a character have been determined by
2718 merging faces of that character, that face is `realized'. The
2719 realization process maps face attributes to what is physically
2720 available on the system where Emacs runs. The result is a `realized
2721 face' in form of an internal structure which is stored in the face
2722 cache of the frame on which it was realized.
2723
2724 Face realization is done in the context of the charset of the
2725 character to display because different fonts and encodings are used
2726 for different charsets. In other words, for characters of different
2727 charsets, different realized faces are needed to display them.
2728
2729 Except for composite characters, faces are always realized for a
2730 specific character set and contain a specific font, even if the face
2731 being realized specifies a fontset. The reason is that the result of
2732 the new font selection stage is better than what can be done with
2733 statically defined font name patterns in fontsets.
2734
2735 In unibyte text, Emacs' charsets aren't applicable; function
2736 `char-charset' reports ASCII for all characters, including those >
2737 0x7f. The X registry and encoding of fonts to use is determined from
2738 the variable `face-default-registry' in this case. The variable is
2739 initialized at Emacs startup time from the font the user specified for
2740 Emacs.
2741
2742 Currently all unibyte text, i.e. all buffers with
2743 `enable-multibyte-characters' nil are displayed with fonts of the same
2744 registry and encoding `face-default-registry'. This is consistent
2745 with the fact that languages can also be set globally, only.
2746
2747 ++++
2748 **** Clearing face caches.
2749
2750 The Lisp function `clear-face-cache' can be called to clear face caches
2751 on all frames. If called with a non-nil argument, it will also unload
2752 unused fonts.
2753
2754 +++
2755 *** Font selection.
2756
2757 Font selection tries to find the best available matching font for a
2758 given (charset, face) combination. This is done slightly differently
2759 for faces specifying a fontset, or a font family name.
2760
2761 If the face specifies a fontset name, that fontset determines a
2762 pattern for fonts of the given charset. If the face specifies a font
2763 family, a font pattern is constructed. Charset symbols have a
2764 property `x-charset-registry' for that purpose that maps a charset to
2765 an XLFD registry and encoding in the font pattern constructed.
2766
2767 Available fonts on the system on which Emacs runs are then matched
2768 against the font pattern. The result of font selection is the best
2769 match for the given face attributes in this font list.
2770
2771 Font selection can be influenced by the user.
2772
2773 The user can specify the relative importance he gives the face
2774 attributes width, height, weight, and slant by setting
2775 face-font-selection-order (faces.el) to a list of face attribute
2776 names. The default is (:width :height :weight :slant), and means
2777 that font selection first tries to find a good match for the font
2778 width specified by a face, then---within fonts with that width---tries
2779 to find a best match for the specified font height, etc.
2780
2781 Setting `face-alternative-font-family-alist' allows the user to
2782 specify alternative font families to try if a family specified by a
2783 face doesn't exist.
2784
2785 +++
2786 **** Scalable fonts
2787
2788 Emacs can make use of scalable fonts but doesn't do so by default,
2789 since the use of too many or too big scalable fonts may crash XFree86
2790 servers.
2791
2792 To enable scalable font use, set the variable
2793 `scalable-fonts-allowed'. A value of nil, the default, means never use
2794 scalable fonts. A value of t means any scalable font may be used.
2795 Otherwise, the value must be a list of regular expressions. A
2796 scalable font may then be used if it matches a regular expression from
2797 that list. Example:
2798
2799 (setq scalable-fonts-allowed '("muleindian-2$"))
2800
2801 allows the use of scalable fonts with registry `muleindian-2'.
2802
2803 +++
2804 *** Functions and variables related to font selection.
2805
2806 - Function: x-family-fonts &optional FAMILY FRAME
2807
2808 Return a list of available fonts of family FAMILY on FRAME. If FAMILY
2809 is omitted or nil, list all families. Otherwise, FAMILY must be a
2810 string, possibly containing wildcards `?' and `*'.
2811
2812 If FRAME is omitted or nil, use the selected frame. Each element of
2813 the result is a vector [FAMILY WIDTH POINT-SIZE WEIGHT SLANT FIXED-P
2814 FULL REGISTRY-AND-ENCODING]. FAMILY is the font family name.
2815 POINT-SIZE is the size of the font in 1/10 pt. WIDTH, WEIGHT, and
2816 SLANT are symbols describing the width, weight and slant of the font.
2817 These symbols are the same as for face attributes. FIXED-P is non-nil
2818 if the font is fixed-pitch. FULL is the full name of the font, and
2819 REGISTRY-AND-ENCODING is a string giving the registry and encoding of
2820 the font. The result list is sorted according to the current setting
2821 of the face font sort order.
2822
2823 - Function: x-font-family-list
2824
2825 Return a list of available font families on FRAME. If FRAME is
2826 omitted or nil, use the selected frame. Value is a list of conses
2827 (FAMILY . FIXED-P) where FAMILY is a font family, and FIXED-P is
2828 non-nil if fonts of that family are fixed-pitch.
2829
2830 - Variable: font-list-limit
2831
2832 Limit for font matching. If an integer > 0, font matching functions
2833 won't load more than that number of fonts when searching for a
2834 matching font. The default is currently 100.
2835
2836 +++
2837 *** Setting face attributes.
2838
2839 For the most part, the new face implementation is interface-compatible
2840 with the old one. Old face attribute related functions are now
2841 implemented in terms of the new functions `set-face-attribute' and
2842 `face-attribute'.
2843
2844 Face attributes are identified by their names which are keyword
2845 symbols. All attributes can be set to `unspecified'.
2846
2847 The following attributes are recognized:
2848
2849 `:family'
2850
2851 VALUE must be a string specifying the font family, e.g. ``courier'',
2852 or a fontset alias name. If a font family is specified, wild-cards `*'
2853 and `?' are allowed.
2854
2855 `:width'
2856
2857 VALUE specifies the relative proportionate width of the font to use.
2858 It must be one of the symbols `ultra-condensed', `extra-condensed',
2859 `condensed', `semi-condensed', `normal', `semi-expanded', `expanded',
2860 `extra-expanded', or `ultra-expanded'.
2861
2862 `:height'
2863
2864 VALUE must be either an integer specifying the height of the font to use
2865 in 1/10 pt, a floating point number specifying the amount by which to
2866 scale any underlying face, or a function, which is called with the old
2867 height (from the underlying face), and should return the new height.
2868
2869 `:weight'
2870
2871 VALUE specifies the weight of the font to use. It must be one of the
2872 symbols `ultra-bold', `extra-bold', `bold', `semi-bold', `normal',
2873 `semi-light', `light', `extra-light', `ultra-light'.
2874
2875 `:slant'
2876
2877 VALUE specifies the slant of the font to use. It must be one of the
2878 symbols `italic', `oblique', `normal', `reverse-italic', or
2879 `reverse-oblique'.
2880
2881 `:foreground', `:background'
2882
2883 VALUE must be a color name, a string.
2884
2885 `:underline'
2886
2887 VALUE specifies whether characters in FACE should be underlined. If
2888 VALUE is t, underline with foreground color of the face. If VALUE is
2889 a string, underline with that color. If VALUE is nil, explicitly
2890 don't underline.
2891
2892 `:overline'
2893
2894 VALUE specifies whether characters in FACE should be overlined. If
2895 VALUE is t, overline with foreground color of the face. If VALUE is a
2896 string, overline with that color. If VALUE is nil, explicitly don't
2897 overline.
2898
2899 `:strike-through'
2900
2901 VALUE specifies whether characters in FACE should be drawn with a line
2902 striking through them. If VALUE is t, use the foreground color of the
2903 face. If VALUE is a string, strike-through with that color. If VALUE
2904 is nil, explicitly don't strike through.
2905
2906 `:box'
2907
2908 VALUE specifies whether characters in FACE should have a box drawn
2909 around them. If VALUE is nil, explicitly don't draw boxes. If
2910 VALUE is t, draw a box with lines of width 1 in the foreground color
2911 of the face. If VALUE is a string, the string must be a color name,
2912 and the box is drawn in that color with a line width of 1. Otherwise,
2913 VALUE must be a property list of the form `(:line-width WIDTH
2914 :color COLOR :style STYLE)'. If a keyword/value pair is missing from
2915 the property list, a default value will be used for the value, as
2916 specified below. WIDTH specifies the width of the lines to draw; it
2917 defaults to 1. COLOR is the name of the color to draw in, default is
2918 the foreground color of the face for simple boxes, and the background
2919 color of the face for 3D boxes. STYLE specifies whether a 3D box
2920 should be draw. If STYLE is `released-button', draw a box looking
2921 like a released 3D button. If STYLE is `pressed-button' draw a box
2922 that appears like a pressed button. If STYLE is nil, the default if
2923 the property list doesn't contain a style specification, draw a 2D
2924 box.
2925
2926 `:inverse-video'
2927
2928 VALUE specifies whether characters in FACE should be displayed in
2929 inverse video. VALUE must be one of t or nil.
2930
2931 `:stipple'
2932
2933 If VALUE is a string, it must be the name of a file of pixmap data.
2934 The directories listed in the `x-bitmap-file-path' variable are
2935 searched. Alternatively, VALUE may be a list of the form (WIDTH
2936 HEIGHT DATA) where WIDTH and HEIGHT are the size in pixels, and DATA
2937 is a string containing the raw bits of the bitmap. VALUE nil means
2938 explicitly don't use a stipple pattern.
2939
2940 For convenience, attributes `:family', `:width', `:height', `:weight',
2941 and `:slant' may also be set in one step from an X font name:
2942
2943 `:font'
2944
2945 Set font-related face attributes from VALUE. VALUE must be a valid
2946 XLFD font name. If it is a font name pattern, the first matching font
2947 is used--this is for compatibility with the behavior of previous
2948 versions of Emacs.
2949
2950 For compatibility with Emacs 20, keywords `:bold' and `:italic' can
2951 be used to specify that a bold or italic font should be used. VALUE
2952 must be t or nil in that case. A value of `unspecified' is not allowed."
2953
2954 Please see also the documentation of `set-face-attribute' and
2955 `defface'.
2956
2957 `:inherit'
2958
2959 VALUE is the name of a face from which to inherit attributes, or a list
2960 of face names. Attributes from inherited faces are merged into the face
2961 like an underlying face would be, with higher priority than underlying faces.
2962
2963 *** Face attributes and X resources
2964
2965 The following X resource names can be used to set face attributes
2966 from X resources:
2967
2968 Face attribute X resource class
2969 -----------------------------------------------------------------------
2970 :family attributeFamily . Face.AttributeFamily
2971 :width attributeWidth Face.AttributeWidth
2972 :height attributeHeight Face.AttributeHeight
2973 :weight attributeWeight Face.AttributeWeight
2974 :slant attributeSlant Face.AttributeSlant
2975 foreground attributeForeground Face.AttributeForeground
2976 :background attributeBackground . Face.AttributeBackground
2977 :overline attributeOverline Face.AttributeOverline
2978 :strike-through attributeStrikeThrough Face.AttributeStrikeThrough
2979 :box attributeBox Face.AttributeBox
2980 :underline attributeUnderline Face.AttributeUnderline
2981 :inverse-video attributeInverse Face.AttributeInverse
2982 :stipple attributeStipple Face.AttributeStipple
2983 or attributeBackgroundPixmap
2984 Face.AttributeBackgroundPixmap
2985 :font attributeFont Face.AttributeFont
2986 :bold attributeBold Face.AttributeBold
2987 :italic attributeItalic . Face.AttributeItalic
2988 :font attributeFont Face.AttributeFont
2989
2990 +++
2991 *** Text property `face'.
2992
2993 The value of the `face' text property can now be a single face
2994 specification or a list of such specifications. Each face
2995 specification can be
2996
2997 1. A symbol or string naming a Lisp face.
2998
2999 2. A property list of the form (KEYWORD VALUE ...) where each
3000 KEYWORD is a face attribute name, and VALUE is an appropriate value
3001 for that attribute. Please see the doc string of `set-face-attribute'
3002 for face attribute names.
3003
3004 3. Conses of the form (FOREGROUND-COLOR . COLOR) or
3005 (BACKGROUND-COLOR . COLOR) where COLOR is a color name. This is
3006 for compatibility with previous Emacs versions.
3007
3008 +++
3009 ** Support functions for colors on text-only terminals.
3010
3011 The function `tty-color-define' can be used to define colors for use
3012 on TTY and MSDOS frames. It maps a color name to a color number on
3013 the terminal. Emacs defines a couple of common color mappings by
3014 default. You can get defined colors with a call to
3015 `defined-colors'. The function `tty-color-clear' can be
3016 used to clear the mapping table.
3017
3018 ** Unified support for colors independent of frame type.
3019
3020 The new functions `defined-colors', `color-defined-p', `color-values',
3021 and `display-color-p' work for any type of frame. On frames whose
3022 type is neither x nor w32, these functions transparently map X-style
3023 color specifications to the closest colors supported by the frame
3024 display. Lisp programs should use these new functions instead of the
3025 old `x-defined-colors', `x-color-defined-p', `x-color-values', and
3026 `x-display-color-p'. (The old function names are still available for
3027 compatibility; they are now aliases of the new names.) Lisp programs
3028 should no more look at the value of the variable window-system to
3029 modify their color-related behavior.
3030
3031 The primitives `color-gray-p' and `color-supported-p' also work for
3032 any frame type.
3033
3034 ** Platform-independent functions to describe display capabilities.
3035
3036 The new functions `display-mouse-p', `display-popup-menus-p',
3037 `display-graphic-p', `display-selections-p', `display-screens',
3038 `display-pixel-width', `display-pixel-height', `display-mm-width',
3039 `display-mm-height', `display-backing-store', `display-save-under',
3040 `display-planes', `display-color-cells', `display-visual-class', and
3041 `display-grayscale-p' describe the basic capabilities of a particular
3042 display. Lisp programs should call these functions instead of testing
3043 the value of the variables `window-system' or `system-type', or calling
3044 platform-specific functions such as `x-display-pixel-width'.
3045
3046 +++
3047 ** The minibuffer prompt is now actually inserted in the minibuffer.
3048
3049 This makes it possible to scroll through the prompt, if you want to.
3050
3051 The function minubuffer-prompt-end returns the current position of the
3052 end of the minibuffer prompt, if the minibuffer is current.
3053 Otherwise, it returns zero.
3054
3055 ** New `field' abstraction in buffers.
3056
3057 There is now code to support an abstraction called `fields' in emacs
3058 buffers. A field is a contiguous region of text with the same `field'
3059 property (which can be a text property or an overlay).
3060
3061 Many emacs functions, such as forward-word, forward-sentence,
3062 forward-paragraph, beginning-of-line, etc., stop moving when they come
3063 to the boundary between fields; beginning-of-line and end-of-line will
3064 not let the point move past the field boundary, but other movement
3065 commands continue into the next field if repeated. Stopping at field
3066 boundaries can be suppressed programmatically by binding
3067 `inhibit-field-text-motion' to a non-nil value around calls to these
3068 functions.
3069
3070 Now that the minibuffer prompt is inserted into the minibuffer, it is in
3071 a separate field from the user-input part of the buffer, so that common
3072 editing commands treat the user's text separately from the prompt.
3073
3074 The following functions are defined for operating on fields:
3075
3076 - Function: constrain-to-field NEW-POS OLD-POS &optional ESCAPE-FROM-EDGE ONLY-IN-LINE INHIBIT-CAPTURE-PROPERTY
3077
3078 Return the position closest to NEW-POS that is in the same field as OLD-POS.
3079
3080 A field is a region of text with the same `field' property.
3081 If NEW-POS is nil, then the current point is used instead, and set to the
3082 constrained position if that is is different.
3083
3084 If OLD-POS is at the boundary of two fields, then the allowable
3085 positions for NEW-POS depends on the value of the optional argument
3086 ESCAPE-FROM-EDGE: If ESCAPE-FROM-EDGE is nil, then NEW-POS is
3087 constrained to the field that has the same `field' char-property
3088 as any new characters inserted at OLD-POS, whereas if ESCAPE-FROM-EDGE
3089 is non-nil, NEW-POS is constrained to the union of the two adjacent
3090 fields. Additionally, if two fields are separated by another field with
3091 the special value `boundary', then any point within this special field is
3092 also considered to be `on the boundary'.
3093
3094 If the optional argument ONLY-IN-LINE is non-nil and constraining
3095 NEW-POS would move it to a different line, NEW-POS is returned
3096 unconstrained. This useful for commands that move by line, like
3097 C-n or C-a, which should generally respect field boundaries
3098 only in the case where they can still move to the right line.
3099
3100 If the optional argument INHIBIT-CAPTURE-PROPERTY is non-nil, and OLD-POS has
3101 a non-nil property of that name, then any field boundaries are ignored.
3102
3103 Field boundaries are not noticed if `inhibit-field-text-motion' is non-nil.
3104
3105 - Function: delete-field &optional POS
3106
3107 Delete the field surrounding POS.
3108 A field is a region of text with the same `field' property.
3109 If POS is nil, the value of point is used for POS.
3110
3111 - Function: field-beginning &optional POS ESCAPE-FROM-EDGE
3112
3113 Return the beginning of the field surrounding POS.
3114 A field is a region of text with the same `field' property.
3115 If POS is nil, the value of point is used for POS.
3116 If ESCAPE-FROM-EDGE is non-nil and POS is at the beginning of its
3117 field, then the beginning of the *previous* field is returned.
3118
3119 - Function: field-end &optional POS ESCAPE-FROM-EDGE
3120
3121 Return the end of the field surrounding POS.
3122 A field is a region of text with the same `field' property.
3123 If POS is nil, the value of point is used for POS.
3124 If ESCAPE-FROM-EDGE is non-nil and POS is at the end of its field,
3125 then the end of the *following* field is returned.
3126
3127 - Function: field-string &optional POS
3128
3129 Return the contents of the field surrounding POS as a string.
3130 A field is a region of text with the same `field' property.
3131 If POS is nil, the value of point is used for POS.
3132
3133 - Function: field-string-no-properties &optional POS
3134
3135 Return the contents of the field around POS, without text-properties.
3136 A field is a region of text with the same `field' property.
3137 If POS is nil, the value of point is used for POS.
3138
3139 +++
3140 ** Image support.
3141
3142 Emacs can now display images. Images are inserted into text by giving
3143 strings or buffer text a `display' text property containing one of
3144 (AREA IMAGE) or IMAGE. The display of the `display' property value
3145 replaces the display of the characters having that property.
3146
3147 If the property value has the form (AREA IMAGE), AREA must be one of
3148 `(margin left-margin)', `(margin right-margin)' or `(margin nil)'. If
3149 AREA is `(margin nil)', IMAGE will be displayed in the text area of a
3150 window, otherwise it will be displayed in the left or right marginal
3151 area.
3152
3153 IMAGE is an image specification.
3154
3155 *** Image specifications
3156
3157 Image specifications are lists of the form `(image PROPS)' where PROPS
3158 is a property list whose keys are keyword symbols. Each
3159 specifications must contain a property `:type TYPE' with TYPE being a
3160 symbol specifying the image type, e.g. `xbm'. Properties not
3161 described below are ignored.
3162
3163 The following is a list of properties all image types share.
3164
3165 `:ascent ASCENT'
3166
3167 ASCENT must be a number in the range 0..100, or the symbol `center'.
3168 If it is a number, it specifies the percentage of the image's height
3169 to use for its ascent.
3170
3171 If not specified, ASCENT defaults to the value 50 which means that the
3172 image will be centered with the base line of the row it appears in.
3173
3174 If ASCENT is `center' the image is vertically centered around a
3175 centerline which is the vertical center of text drawn at the position
3176 of the image, in the manner specified by the text properties and
3177 overlays that apply to the image.
3178
3179 `:margin MARGIN'
3180
3181 MARGIN must be a number >= 0 specifying how many pixels to put as
3182 margin around the image. Default is 0.
3183
3184 `:relief RELIEF'
3185
3186 RELIEF is analogous to the `:relief' attribute of faces. Puts a relief
3187 around an image.
3188
3189 `:algorithm ALGO'
3190
3191 Apply an image algorithm to the image before displaying it.
3192
3193 ALGO `laplace' or `emboss' means apply a Laplace or ``emboss''
3194 edge-detection algorithm to the image.
3195
3196 ALGO `(edge-detection :matrix MATRIX :color-adjust ADJUST)' means
3197 apply a general edge-detection algorithm. MATRIX must be either a
3198 nine-element list or a nine-element vector of numbers. A pixel at
3199 position x/y in the transformed image is computed from original pixels
3200 around that position. MATRIX specifies, for each pixel in the
3201 neighborhood of x/y, a factor with which that pixel will influence the
3202 transformed pixel; element 0 specifies the factor for the pixel at
3203 x-1/y-1, element 1 the factor for the pixel at x/y-1 etc. as shown
3204 below.
3205
3206 (x-1/y-1 x/y-1 x+1/y-1
3207 x-1/y x/y x+1/y
3208 x-1/y+1 x/y+1 x+1/y+1)
3209
3210 The resulting pixel is computed from the color intensity of the color
3211 resulting from summing up the RGB values of surrounding pixels,
3212 multiplied by the specified factors, and dividing that sum by the sum
3213 of the factors' absolute values.
3214
3215 Laplace edge-detection currently uses a matrix of
3216
3217 (1 0 0
3218 0 0 0
3219 9 9 -1)
3220
3221 Emboss edge-detection uses a matrix of
3222
3223 ( 2 -1 0
3224 -1 0 1
3225 0 1 -2)
3226
3227 ALGO `disabled' means transform the image so that it looks
3228 ``disabled''.
3229
3230 `:mask MASK'
3231
3232 If MASK is `heuristic' or `(heuristic BG)', build a clipping mask for
3233 the image, so that the background of a frame is visible behind the
3234 image. If BG is not specified, or if BG is t, determine the
3235 background color of the image by looking at the 4 corners of the
3236 image, assuming the most frequently occuring color from the corners is
3237 the background color of the image. Otherwise, BG must be a list `(RED
3238 GREEN BLUE)' specifying the color to assume for the background of the
3239 image.
3240
3241 If MASK is nil, remove a mask from the image, if it has one. Images
3242 in some formats include a mask which can be removed by specifying
3243 `:mask nil'.
3244
3245 `:file FILE'
3246
3247 Load image from FILE. If FILE is not absolute after expanding it,
3248 search for the image in `data-directory'. Some image types support
3249 building images from data. When this is done, no `:file' property
3250 may be present in the image specification.
3251
3252 `:data DATA'
3253
3254 Get image data from DATA. (As of this writing, this is not yet
3255 supported for image type `postscript'). Either :file or :data may be
3256 present in an image specification, but not both. All image types
3257 support strings as DATA, some types allow additional types of DATA.
3258
3259 *** Supported image types
3260
3261 **** XBM, image type `xbm'.
3262
3263 XBM images don't require an external library. Additional image
3264 properties supported are
3265
3266 `:foreground FG'
3267
3268 FG must be a string specifying the image foreground color. Default
3269 is the frame's foreground.
3270
3271 `:background FG'
3272
3273 BG must be a string specifying the image foreground color. Default is
3274 the frame's background color.
3275
3276 XBM images can be constructed from data instead of file. In this
3277 case, the image specification must contain the following properties
3278 instead of a `:file' property.
3279
3280 `:width WIDTH'
3281
3282 WIDTH specifies the width of the image in pixels.
3283
3284 `:height HEIGHT'
3285
3286 HEIGHT specifies the height of the image in pixels.
3287
3288 `:data DATA'
3289
3290 DATA must be either
3291
3292 1. a string large enough to hold the bitmap data, i.e. it must
3293 have a size >= (WIDTH + 7) / 8 * HEIGHT
3294
3295 2. a bool-vector of size >= WIDTH * HEIGHT
3296
3297 3. a vector of strings or bool-vectors, one for each line of the
3298 bitmap.
3299
3300 4. a string that's an in-memory XBM file. Neither width nor
3301 height may be specified in this case because these are defined
3302 in the file.
3303
3304 **** XPM, image type `xpm'
3305
3306 XPM images require the external library `libXpm', package
3307 `xpm-3.4k.tar.gz', version 3.4k or later. Make sure the library is
3308 found when Emacs is configured by supplying appropriate paths via
3309 `--x-includes' and `--x-libraries'.
3310
3311 Additional image properties supported are:
3312
3313 `:color-symbols SYMBOLS'
3314
3315 SYMBOLS must be a list of pairs (NAME . COLOR), with NAME being the
3316 name of color as it appears in an XPM file, and COLOR being an X color
3317 name.
3318
3319 XPM images can be built from memory instead of files. In that case,
3320 add a `:data' property instead of a `:file' property.
3321
3322 The XPM library uses libz in its implementation so that it is able
3323 to display compressed images.
3324
3325 **** PBM, image type `pbm'
3326
3327 PBM images don't require an external library. Color, gray-scale and
3328 mono images are supported. There are no additional image properties
3329 defined.
3330
3331 **** JPEG, image type `jpeg'
3332
3333 Support for JPEG images requires the external library `libjpeg',
3334 package `jpegsrc.v6a.tar.gz', or later. Additional image properties
3335 are:
3336
3337 **** TIFF, image type `tiff'
3338
3339 Support for TIFF images requires the external library `libtiff',
3340 package `tiff-v3.4-tar.gz', or later. There are no additional image
3341 properties defined.
3342
3343 **** GIF, image type `gif'
3344
3345 Support for GIF images requires the external library `libungif', package
3346 `libungif-4.1.0', or later.
3347
3348 Additional image properties supported are:
3349
3350 `:index INDEX'
3351
3352 INDEX must be an integer >= 0. Load image number INDEX from a
3353 multi-image GIF file. An error is signalled if INDEX is too large.
3354
3355 This could be used to implement limited support for animated GIFs.
3356 For example, the following function displays a multi-image GIF file
3357 at point-min in the current buffer, switching between sub-images
3358 every 0.1 seconds.
3359
3360 (defun show-anim (file max)
3361 "Display multi-image GIF file FILE which contains MAX subimages."
3362 (display-anim (current-buffer) file 0 max t))
3363
3364 (defun display-anim (buffer file idx max first-time)
3365 (when (= idx max)
3366 (setq idx 0))
3367 (let ((img (create-image file nil nil :index idx)))
3368 (save-excursion
3369 (set-buffer buffer)
3370 (goto-char (point-min))
3371 (unless first-time (delete-char 1))
3372 (insert-image img "x"))
3373 (run-with-timer 0.1 nil 'display-anim buffer file (1+ idx) max nil)))
3374
3375 **** PNG, image type `png'
3376
3377 Support for PNG images requires the external library `libpng',
3378 package `libpng-1.0.2.tar.gz', or later. There are no additional image
3379 properties defined.
3380
3381 **** Ghostscript, image type `postscript'.
3382
3383 Additional image properties supported are:
3384
3385 `:pt-width WIDTH'
3386
3387 WIDTH is width of the image in pt (1/72 inch). WIDTH must be an
3388 integer. This is a required property.
3389
3390 `:pt-height HEIGHT'
3391
3392 HEIGHT specifies the height of the image in pt (1/72 inch). HEIGHT
3393 must be a integer. This is an required property.
3394
3395 `:bounding-box BOX'
3396
3397 BOX must be a list or vector of 4 integers giving the bounding box of
3398 the PS image, analogous to the `BoundingBox' comment found in PS
3399 files. This is an required property.
3400
3401 Part of the Ghostscript interface is implemented in Lisp. See
3402 lisp/gs.el.
3403
3404 *** Lisp interface.
3405
3406 The variable `image-types' contains a list of those image types
3407 which are supported in the current configuration.
3408
3409 Images are stored in an image cache and removed from the cache when
3410 they haven't been displayed for `image-cache-eviction-delay seconds.
3411 The function `clear-image-cache' can be used to clear the image cache
3412 manually. Images in the cache are compared with `equal', i.e. all
3413 images with `equal' specifications share the same image.
3414
3415 *** Simplified image API, image.el
3416
3417 The new Lisp package image.el contains functions that simplify image
3418 creation and putting images into text. The function `create-image'
3419 can be used to create images. The macro `defimage' can be used to
3420 define an image based on available image types. The functions
3421 `put-image' and `insert-image' can be used to insert an image into a
3422 buffer.
3423
3424 +++
3425 ** Display margins.
3426
3427 Windows can now have margins which are used for special text
3428 and images.
3429
3430 To give a window margins, either set the buffer-local variables
3431 `left-margin-width' and `right-margin-width', or call
3432 `set-window-margins'. The function `window-margins' can be used to
3433 obtain the current settings. To make `left-margin-width' and
3434 `right-margin-width' take effect, you must set them before displaying
3435 the buffer in a window, or use `set-window-buffer' to force an update
3436 of the display margins.
3437
3438 You can put text in margins by giving it a `display' text property
3439 containing a pair of the form `(LOCATION . VALUE)', where LOCATION is
3440 one of `left-margin' or `right-margin' or nil. VALUE can be either a
3441 string, an image specification or a stretch specification (see later
3442 in this file).
3443
3444 +++
3445 ** Help display
3446
3447 Emacs displays short help messages in the echo area, when the mouse
3448 moves over a tool-bar item or a piece of text that has a text property
3449 `help-echo'. This feature also applies to strings in the mode line
3450 that have a `help-echo' property.
3451
3452 If the value of the `help-echo' property is a function, that function
3453 is called with three arguments WINDOW, OBJECT and POSITION. WINDOW is
3454 the window in which the help was found.
3455
3456 If OBJECT is a buffer, POS is the position in the buffer where the
3457 `help-echo' text property was found.
3458
3459 If OBJECT is an overlay, that overlay has a `help-echo' property, and
3460 POS is the position in the overlay's buffer under the mouse.
3461
3462 If OBJECT is a string (an overlay string or a string displayed with
3463 the `display' property), POS is the position in that string under the
3464 mouse.
3465
3466 If the value of the `help-echo' property is neither a function nor a
3467 string, it is evaluated to obtain a help string.
3468
3469 For tool-bar and menu-bar items, their key definition is used to
3470 determine the help to display. If their definition contains a
3471 property `:help FORM', FORM is evaluated to determine the help string.
3472 For tool-bar items without a help form, the caption of the item is
3473 used as help string.
3474
3475 The hook `show-help-function' can be set to a function that displays
3476 the help string differently. For example, enabling a tooltip window
3477 causes the help display to appear there instead of in the echo area.
3478
3479 +++
3480 ** Vertical fractional scrolling.
3481
3482 The display of text in windows can be scrolled smoothly in pixels.
3483 This is useful, for example, for making parts of large images visible.
3484
3485 The function `window-vscroll' returns the current value of vertical
3486 scrolling, a non-negative fraction of the canonical character height.
3487 The function `set-window-vscroll' can be used to set the vertical
3488 scrolling value. Here is an example of how these function might be
3489 used.
3490
3491 (global-set-key [A-down]
3492 #'(lambda ()
3493 (interactive)
3494 (set-window-vscroll (selected-window)
3495 (+ 0.5 (window-vscroll)))))
3496 (global-set-key [A-up]
3497 #'(lambda ()
3498 (interactive)
3499 (set-window-vscroll (selected-window)
3500 (- (window-vscroll) 0.5)))))
3501
3502 +++
3503 ** New hook `fontification-functions'.
3504
3505 Functions from `fontification-functions' are called from redisplay
3506 when it encounters a region of text that is not yet fontified. This
3507 variable automatically becomes buffer-local when set. Each function
3508 is called with one argument, POS.
3509
3510 At least one of the hook functions should fontify one or more
3511 characters starting at POS in the current buffer. It should mark them
3512 as fontified by giving them a non-nil value of the `fontified' text
3513 property. It may be reasonable for these functions to check for the
3514 `fontified' property and not put it back on, but they do not have to.
3515
3516 +++
3517 ** Tool bar support.
3518
3519 Emacs supports a tool bar at the top of a frame under X. The frame
3520 parameter `tool-bar-lines' (X resource "toolBar", class "ToolBar")
3521 controls how may lines to reserve for the tool bar. A zero value
3522 suppresses the tool bar. If the value is non-zero and
3523 `auto-resize-tool-bars' is non-nil the tool bar's size will be changed
3524 automatically so that all tool bar items are visible.
3525
3526 *** Tool bar item definitions
3527
3528 Tool bar items are defined using `define-key' with a prefix-key
3529 `tool-bar'. For example `(define-key global-map [tool-bar item1] ITEM)'
3530 where ITEM is a list `(menu-item CAPTION BINDING PROPS...)'.
3531
3532 CAPTION is the caption of the item, If it's not a string, it is
3533 evaluated to get a string. The caption is currently not displayed in
3534 the tool bar, but it is displayed if the item doesn't have a `:help'
3535 property (see below).
3536
3537 BINDING is the tool bar item's binding. Tool bar items with keymaps as
3538 binding are currently ignored.
3539
3540 The following properties are recognized:
3541
3542 `:enable FORM'.
3543
3544 FORM is evaluated and specifies whether the tool bar item is enabled
3545 or disabled.
3546
3547 `:visible FORM'
3548
3549 FORM is evaluated and specifies whether the tool bar item is displayed.
3550
3551 `:filter FUNCTION'
3552
3553 FUNCTION is called with one parameter, the same list BINDING in which
3554 FUNCTION is specified as the filter. The value FUNCTION returns is
3555 used instead of BINDING to display this item.
3556
3557 `:button (TYPE SELECTED)'
3558
3559 TYPE must be one of `:radio' or `:toggle'. SELECTED is evaluated
3560 and specifies whether the button is selected (pressed) or not.
3561
3562 `:image IMAGES'
3563
3564 IMAGES is either a single image specification or a vector of four
3565 image specifications. If it is a vector, this table lists the
3566 meaning of each of the four elements:
3567
3568 Index Use when item is
3569 ----------------------------------------
3570 0 enabled and selected
3571 1 enabled and deselected
3572 2 disabled and selected
3573 3 disabled and deselected
3574
3575 If IMAGE is a single image specification, a Laplace edge-detection
3576 algorithm is used on that image to draw the image in disabled state.
3577
3578 `:help HELP-STRING'.
3579
3580 Gives a help string to display for the tool bar item. This help
3581 is displayed when the mouse is moved over the item.
3582
3583 The function `toolbar-add-item' is a convenience function for adding
3584 toolbar items generally, and `tool-bar-add-item-from-menu' can be used
3585 to define a toolbar item with a binding copied from an item on the
3586 menu bar.
3587
3588 *** Tool-bar-related variables.
3589
3590 If `auto-resize-tool-bar' is non-nil, the tool bar will automatically
3591 resize to show all defined tool bar items. It will never grow larger
3592 than 1/4 of the frame's size.
3593
3594 If `auto-raise-tool-bar-buttons' is non-nil, tool bar buttons will be
3595 raised when the mouse moves over them.
3596
3597 You can add extra space between tool bar items by setting
3598 `tool-bar-button-margin' to a positive integer specifying a number of
3599 pixels. Default is 1.
3600
3601 You can change the shadow thickness of tool bar buttons by setting
3602 `tool-bar-button-relief' to an integer. Default is 3.
3603
3604 *** Tool-bar clicks with modifiers.
3605
3606 You can bind commands to clicks with control, shift, meta etc. on
3607 a tool bar item. If
3608
3609 (define-key global-map [tool-bar shell]
3610 '(menu-item "Shell" shell
3611 :image (image :type xpm :file "shell.xpm")))
3612
3613 is the original tool bar item definition, then
3614
3615 (define-key global-map [tool-bar S-shell] 'some-command)
3616
3617 makes a binding to run `some-command' for a shifted click on the same
3618 item.
3619
3620 ** Mode line changes.
3621
3622 +++
3623 *** Mouse-sensitive mode line.
3624
3625 The mode line can be made mouse-sensitive by displaying strings there
3626 that have a `local-map' text property. There are three ways to display
3627 a string with a `local-map' property in the mode line.
3628
3629 1. The mode line spec contains a variable whose string value has
3630 a `local-map' text property.
3631
3632 2. The mode line spec contains a format specifier (e.g. `%12b'), and
3633 that format specifier has a `local-map' property.
3634
3635 3. The mode line spec contains a list containing `:eval FORM'. FORM
3636 is evaluated. If the result is a string, and that string has a
3637 `local-map' property.
3638
3639 The same mechanism is used to determine the `face' and `help-echo'
3640 properties of strings in the mode line. See `bindings.el' for an
3641 example.
3642
3643 *** If a mode line element has the form `(:eval FORM)', FORM is
3644 evaluated and the result is used as mode line element.
3645
3646 +++
3647 *** You can suppress mode-line display by setting the buffer-local
3648 variable mode-line-format to nil.
3649
3650 +++
3651 *** A headerline can now be displayed at the top of a window.
3652
3653 This mode line's contents are controlled by the new variable
3654 `header-line-format' and `default-header-line-format' which are
3655 completely analogous to `mode-line-format' and
3656 `default-mode-line-format'. A value of nil means don't display a top
3657 line.
3658
3659 The appearance of top mode lines is controlled by the face
3660 `header-line'.
3661
3662 The function `coordinates-in-window-p' returns `header-line' for a
3663 position in the header-line.
3664
3665 +++
3666 ** Text property `display'
3667
3668 The `display' text property is used to insert images into text,
3669 replace text with other text, display text in marginal area, and it is
3670 also used to control other aspects of how text displays. The value of
3671 the `display' property should be a display specification, as described
3672 below, or a list or vector containing display specifications.
3673
3674 *** Replacing text, displaying text in marginal areas
3675
3676 To replace the text having the `display' property with some other
3677 text, use a display specification of the form `(LOCATION STRING)'.
3678
3679 If LOCATION is `(margin left-margin)', STRING is displayed in the left
3680 marginal area, if it is `(margin right-margin)', it is displayed in
3681 the right marginal area, and if LOCATION is `(margin nil)' STRING
3682 is displayed in the text. In the latter case you can also use the
3683 simpler form STRING as property value.
3684
3685 *** Variable width and height spaces
3686
3687 To display a space of fractional width or height, use a display
3688 specification of the form `(LOCATION STRECH)'. If LOCATION is
3689 `(margin left-margin)', the space is displayed in the left marginal
3690 area, if it is `(margin right-margin)', it is displayed in the right
3691 marginal area, and if LOCATION is `(margin nil)' the space is
3692 displayed in the text. In the latter case you can also use the
3693 simpler form STRETCH as property value.
3694
3695 The stretch specification STRETCH itself is a list of the form `(space
3696 PROPS)', where PROPS is a property list which can contain the
3697 properties described below.
3698
3699 The display of the fractional space replaces the display of the
3700 characters having the `display' property.
3701
3702 - :width WIDTH
3703
3704 Specifies that the space width should be WIDTH times the normal
3705 character width. WIDTH can be an integer or floating point number.
3706
3707 - :relative-width FACTOR
3708
3709 Specifies that the width of the stretch should be computed from the
3710 first character in a group of consecutive characters that have the
3711 same `display' property. The computation is done by multiplying the
3712 width of that character by FACTOR.
3713
3714 - :align-to HPOS
3715
3716 Specifies that the space should be wide enough to reach HPOS. The
3717 value HPOS is measured in units of the normal character width.
3718
3719 Exactly one of the above properties should be used.
3720
3721 - :height HEIGHT
3722
3723 Specifies the height of the space, as HEIGHT, measured in terms of the
3724 normal line height.
3725
3726 - :relative-height FACTOR
3727
3728 The height of the space is computed as the product of the height
3729 of the text having the `display' property and FACTOR.
3730
3731 - :ascent ASCENT
3732
3733 Specifies that ASCENT percent of the height of the stretch should be
3734 used for the ascent of the stretch, i.e. for the part above the
3735 baseline. The value of ASCENT must be a non-negative number less or
3736 equal to 100.
3737
3738 You should not use both `:height' and `:relative-height' together.
3739
3740 *** Images
3741
3742 A display specification for an image has the form `(LOCATION
3743 . IMAGE)', where IMAGE is an image specification. The image replaces,
3744 in the display, the characters having this display specification in
3745 their `display' text property. If LOCATION is `(margin left-margin)',
3746 the image will be displayed in the left marginal area, if it is
3747 `(margin right-margin)' it will be displayed in the right marginal
3748 area, and if LOCATION is `(margin nil)' the image will be displayed in
3749 the text. In the latter case you can also use the simpler form IMAGE
3750 as display specification.
3751
3752 *** Other display properties
3753
3754 - :space-width FACTOR
3755
3756 Specifies that space characters in the text having that property
3757 should be displayed FACTOR times as wide as normal; FACTOR must be an
3758 integer or float.
3759
3760 - :height HEIGHT
3761
3762 Display text having this property in a font that is smaller or larger.
3763
3764 If HEIGHT is a list of the form `(+ N)', where N is an integer, that
3765 means to use a font that is N steps larger. If HEIGHT is a list of
3766 the form `(- N)', that means to use a font that is N steps smaller. A
3767 ``step'' is defined by the set of available fonts; each size for which
3768 a font is available counts as a step.
3769
3770 If HEIGHT is a number, that means to use a font that is HEIGHT times
3771 as tall as the frame's default font.
3772
3773 If HEIGHT is a symbol, it is called as a function with the current
3774 height as argument. The function should return the new height to use.
3775
3776 Otherwise, HEIGHT is evaluated to get the new height, with the symbol
3777 `height' bound to the current specified font height.
3778
3779 - :raise FACTOR
3780
3781 FACTOR must be a number, specifying a multiple of the current
3782 font's height. If it is positive, that means to display the characters
3783 raised. If it is negative, that means to display them lower down. The
3784 amount of raising or lowering is computed without taking account of the
3785 `:height' subproperty.
3786
3787 *** Conditional display properties
3788
3789 All display specifications can be conditionalized. If a specification
3790 has the form `(:when CONDITION . SPEC)', the specification SPEC
3791 applies only when CONDITION yields a non-nil value when evaluated.
3792 During evaluattion, point is temporarily set to the end position of
3793 the text having the `display' property.
3794
3795 The normal specification consisting of SPEC only is equivalent to
3796 `(:when t SPEC)'.
3797
3798 +++
3799 ** New menu separator types.
3800
3801 Emacs now supports more than one menu separator type. Menu items with
3802 item names consisting of dashes only (including zero dashes) are
3803 treated like before. In addition, the following item names are used
3804 to specify other menu separator types.
3805
3806 - `--no-line' or `--space', or `--:space', or `--:noLine'
3807
3808 No separator lines are drawn, but a small space is inserted where the
3809 separator occurs.
3810
3811 - `--single-line' or `--:singleLine'
3812
3813 A single line in the menu's foreground color.
3814
3815 - `--double-line' or `--:doubleLine'
3816
3817 A double line in the menu's foreground color.
3818
3819 - `--single-dashed-line' or `--:singleDashedLine'
3820
3821 A single dashed line in the menu's foreground color.
3822
3823 - `--double-dashed-line' or `--:doubleDashedLine'
3824
3825 A double dashed line in the menu's foreground color.
3826
3827 - `--shadow-etched-in' or `--:shadowEtchedIn'
3828
3829 A single line with 3D sunken appearance. This is the the form
3830 displayed for item names consisting of dashes only.
3831
3832 - `--shadow-etched-out' or `--:shadowEtchedOut'
3833
3834 A single line with 3D raised appearance.
3835
3836 - `--shadow-etched-in-dash' or `--:shadowEtchedInDash'
3837
3838 A single dashed line with 3D sunken appearance.
3839
3840 - `--shadow-etched-out-dash' or `--:shadowEtchedOutDash'
3841
3842 A single dashed line with 3D raise appearance.
3843
3844 - `--shadow-double-etched-in' or `--:shadowDoubleEtchedIn'
3845
3846 Two lines with 3D sunken appearance.
3847
3848 - `--shadow-double-etched-out' or `--:shadowDoubleEtchedOut'
3849
3850 Two lines with 3D raised appearance.
3851
3852 - `--shadow-double-etched-in-dash' or `--:shadowDoubleEtchedInDash'
3853
3854 Two dashed lines with 3D sunken appearance.
3855
3856 - `--shadow-double-etched-out-dash' or `--:shadowDoubleEtchedOutDash'
3857
3858 Two dashed lines with 3D raised appearance.
3859
3860 Under LessTif/Motif, the last four separator types are displayed like
3861 the corresponding single-line separators.
3862
3863 +++
3864 ** New frame parameters for scroll bar colors.
3865
3866 The new frame parameters `scroll-bar-foreground' and
3867 `scroll-bar-background' can be used to change scroll bar colors.
3868 Their value must be either a color name, a string, or nil to specify
3869 that scroll bars should use a default color. For toolkit scroll bars,
3870 default colors are toolkit specific. For non-toolkit scroll bars, the
3871 default background is the background color of the frame, and the
3872 default foreground is black.
3873
3874 The X resource name of these parameters are `scrollBarForeground'
3875 (class ScrollBarForeground) and `scrollBarBackground' (class
3876 `ScrollBarBackground').
3877
3878 Setting these parameters overrides toolkit specific X resource
3879 settings for scroll bar colors.
3880
3881 +++
3882 ** You can set `redisplay-dont-pause' to a non-nil value to prevent
3883 display updates from being interrupted when input is pending.
3884
3885 ---
3886 ** Changing a window's width may now change its window start if it
3887 starts on a continuation line. The new window start is computed based
3888 on the window's new width, starting from the start of the continued
3889 line as the start of the screen line with the minimum distance from
3890 the original window start.
3891
3892 ---
3893 ** The variable `hscroll-step' and the functions
3894 `hscroll-point-visible' and `hscroll-window-column' have been removed
3895 now that proper horizontal scrolling is implemented.
3896
3897 +++
3898 ** Windows can now be made fixed-width and/or fixed-height.
3899
3900 A window is fixed-size if its buffer has a buffer-local variable
3901 `window-size-fixed' whose value is not nil. A value of `height' makes
3902 windows fixed-height, a value of `width' makes them fixed-width, any
3903 other non-nil value makes them both fixed-width and fixed-height.
3904
3905 The following code makes all windows displaying the current buffer
3906 fixed-width and fixed-height.
3907
3908 (set (make-local-variable 'window-size-fixed) t)
3909
3910 A call to enlarge-window on a window gives an error if that window is
3911 fixed-width and it is tried to change the window's width, or if the
3912 window is fixed-height, and it is tried to change its height. To
3913 change the size of a fixed-size window, bind `window-size-fixed'
3914 temporarily to nil, for example
3915
3916 (let ((window-size-fixed nil))
3917 (enlarge-window 10))
3918
3919 Likewise, an attempt to split a fixed-height window vertically,
3920 or a fixed-width window horizontally results in a error.
3921
3922 ** The cursor-type frame parameter is now supported on MS-DOS
3923 terminals. When Emacs starts, it by default changes the cursor shape
3924 to a solid box, as it does on Unix. The `cursor-type' frame parameter
3925 overrides this as it does on Unix, except that the bar cursor is
3926 horizontal rather than vertical (since the MS-DOS display doesn't
3927 support a vertical-bar cursor).
3928
3929
3930 ^L
3931 * Emacs 20.7 is a bug-fix release with few user-visible changes
3932
3933 ** It is now possible to use CCL-based coding systems for keyboard
3934 input.
3935
3936 ** ange-ftp now handles FTP security extensions, like Kerberos.
3937
3938 ** Rmail has been extended to recognize more forms of digest messages.
3939
3940 ** Now, most coding systems set in keyboard coding system work not
3941 only for character input, but also in incremental search. The
3942 exceptions are such coding systems that handle 2-byte character sets
3943 (e.g euc-kr, euc-jp) and that use ISO's escape sequence
3944 (e.g. iso-2022-jp). They are ignored in incremental search.
3945
3946 ** Support for Macintosh PowerPC-based machines running GNU/Linux has
3947 been added.
3948
3949 ^L
3950 * Emacs 20.6 is a bug-fix release with one user-visible change
3951
3952 ** Support for ARM-based non-RISCiX machines has been added.
3953
3954 ^L
3955 * Emacs 20.5 is a bug-fix release with no user-visible changes.
3956
3957 ** Not new, but not mentioned before:
3958 M-w when Transient Mark mode is enabled disables the mark.
3959 \f
3960 * Changes in Emacs 20.4
3961
3962 ** Init file may be called .emacs.el.
3963
3964 You can now call the Emacs init file `.emacs.el'.
3965 Formerly the name had to be `.emacs'. If you use the name
3966 `.emacs.el', you can byte-compile the file in the usual way.
3967
3968 If both `.emacs' and `.emacs.el' exist, the latter file
3969 is the one that is used.
3970
3971 ** shell-command, and shell-command-on-region, now return
3972 the exit code of the command (unless it is asynchronous).
3973 Also, you can specify a place to put the error output,
3974 separate from the command's regular output.
3975 Interactively, the variable shell-command-default-error-buffer
3976 says where to put error output; set it to a buffer name.
3977 In calls from Lisp, an optional argument ERROR-BUFFER specifies
3978 the buffer name.
3979
3980 When you specify a non-nil error buffer (or buffer name), any error
3981 output is inserted before point in that buffer, with \f\n to separate
3982 it from the previous batch of error output. The error buffer is not
3983 cleared, so error output from successive commands accumulates there.
3984
3985 ** Setting the default value of enable-multibyte-characters to nil in
3986 the .emacs file, either explicitly using setq-default, or via Custom,
3987 is now essentially equivalent to using --unibyte: all buffers
3988 created during startup will be made unibyte after loading .emacs.
3989
3990 ** C-x C-f now handles the wildcards * and ? in file names. For
3991 example, typing C-x C-f c*.c RET visits all the files whose names
3992 match c*.c. To visit a file whose name contains * or ?, add the
3993 quoting sequence /: to the beginning of the file name.
3994
3995 ** The M-x commands keep-lines, flush-lines and count-matches
3996 now have the same feature as occur and query-replace:
3997 if the pattern contains any upper case letters, then
3998 they never ignore case.
3999
4000 ** The end-of-line format conversion feature previously mentioned
4001 under `* Emacs 20.1 changes for MS-DOS and MS-Windows' actually
4002 applies to all operating systems. Emacs recognizes from the contents
4003 of a file what convention it uses to separate lines--newline, CRLF, or
4004 just CR--and automatically converts the contents to the normal Emacs
4005 convention (using newline to separate lines) for editing. This is a
4006 part of the general feature of coding system conversion.
4007
4008 If you subsequently save the buffer, Emacs converts the text back to
4009 the same format that was used in the file before.
4010
4011 You can turn off end-of-line conversion by setting the variable
4012 `inhibit-eol-conversion' to non-nil, e.g. with Custom in the MULE group.
4013
4014 ** The character set property `prefered-coding-system' has been
4015 renamed to `preferred-coding-system', for the sake of correct spelling.
4016 This is a fairly internal feature, so few programs should be affected.
4017
4018 ** Mode-line display of end-of-line format is changed.
4019 The indication of the end-of-line format of the file visited by a
4020 buffer is now more explicit when that format is not the usual one for
4021 your operating system. For example, the DOS-style end-of-line format
4022 is displayed as "(DOS)" on Unix and GNU/Linux systems. The usual
4023 end-of-line format is still displayed as a single character (colon for
4024 Unix, backslash for DOS and Windows, and forward slash for the Mac).
4025
4026 The values of the variables eol-mnemonic-unix, eol-mnemonic-dos,
4027 eol-mnemonic-mac, and eol-mnemonic-undecided, which are strings,
4028 control what is displayed in the mode line for each end-of-line
4029 format. You can now customize these variables.
4030
4031 ** In the previous version of Emacs, tar-mode didn't work well if a
4032 filename contained non-ASCII characters. Now this is fixed. Such a
4033 filename is decoded by file-name-coding-system if the default value of
4034 enable-multibyte-characters is non-nil.
4035
4036 ** The command temp-buffer-resize-mode toggles a minor mode
4037 in which temporary buffers (such as help buffers) are given
4038 windows just big enough to hold the whole contents.
4039
4040 ** If you use completion.el, you must now run the function
4041 dynamic-completion-mode to enable it. Just loading the file
4042 doesn't have any effect.
4043
4044 ** In Flyspell mode, the default is now to make just one Ispell process,
4045 not one per buffer.
4046
4047 ** If you use iswitchb but do not call (iswitchb-default-keybindings) to
4048 use the default keybindings, you will need to add the following line:
4049 (add-hook 'minibuffer-setup-hook 'iswitchb-minibuffer-setup)
4050
4051 ** Auto-show mode is no longer enabled just by loading auto-show.el.
4052 To control it, set `auto-show-mode' via Custom or use the
4053 `auto-show-mode' command.
4054
4055 ** Handling of X fonts' ascent/descent parameters has been changed to
4056 avoid redisplay problems. As a consequence, compared with previous
4057 versions the line spacing and frame size now differ with some font
4058 choices, typically increasing by a pixel per line. This change
4059 occurred in version 20.3 but was not documented then.
4060
4061 ** If you select the bar cursor style, it uses the frame's
4062 cursor-color, rather than the cursor foreground pixel.
4063
4064 ** In multibyte mode, Rmail decodes incoming MIME messages using the
4065 character set specified in the message. If you want to disable this
4066 feature, set the variable rmail-decode-mime-charset to nil.
4067
4068 ** Not new, but not mentioned previously in NEWS: when you use #! at
4069 the beginning of a file to make it executable and specify an
4070 interpreter program, Emacs looks on the second line for the -*- mode
4071 and variable specification, as well as on the first line.
4072
4073 ** Support for IBM codepage encoding of non-ASCII characters.
4074
4075 The new command M-x codepage-setup creates a special coding system
4076 that can be used to convert text between a specific IBM codepage and
4077 one of the character sets built into Emacs which matches that
4078 codepage. For example, codepage 850 corresponds to Latin-1 character
4079 set, codepage 855 corresponds to Cyrillic-ISO character set, etc.
4080
4081 Windows codepages 1250, 1251 and some others, where Windows deviates
4082 from the corresponding ISO character set, are also supported.
4083
4084 IBM box-drawing characters and other glyphs which don't have
4085 equivalents in the corresponding ISO character set, are converted to
4086 a character defined by dos-unsupported-char-glyph on MS-DOS, and to
4087 `?' on other systems.
4088
4089 IBM codepages are widely used on MS-DOS and MS-Windows, so this
4090 feature is most useful on those platforms, but it can also be used on
4091 Unix.
4092
4093 Emacs compiled for MS-DOS automatically loads the support for the
4094 current codepage when it starts.
4095
4096 ** Mail changes
4097
4098 *** When mail is sent using compose-mail (C-x m), and if
4099 `mail-send-nonascii' is set to the new default value `mime',
4100 appropriate MIME headers are added. The headers are added only if
4101 non-ASCII characters are present in the body of the mail, and no other
4102 MIME headers are already present. For example, the following three
4103 headers are added if the coding system used in the *mail* buffer is
4104 latin-1:
4105
4106 MIME-version: 1.0
4107 Content-type: text/plain; charset=iso-8859-1
4108 Content-Transfer-Encoding: 8bit
4109
4110 *** The new variable default-sendmail-coding-system specifies the
4111 default way to encode outgoing mail. This has higher priority than
4112 default-buffer-file-coding-system but has lower priority than
4113 sendmail-coding-system and the local value of
4114 buffer-file-coding-system.
4115
4116 You should not set this variable manually. Instead, set
4117 sendmail-coding-system to specify a fixed encoding for all outgoing
4118 mail.
4119
4120 *** When you try to send a message that contains non-ASCII characters,
4121 if the coding system specified by those variables doesn't handle them,
4122 Emacs will ask you to select a suitable coding system while showing a
4123 list of possible coding systems.
4124
4125 ** CC Mode changes
4126
4127 *** c-default-style can now take an association list that maps major
4128 modes to style names. When this variable is an alist, Java mode no
4129 longer hardcodes a setting to "java" style. See the variable's
4130 docstring for details.
4131
4132 *** It's now possible to put a list as the offset on a syntactic
4133 symbol. The list is evaluated recursively until a non-nil offset is
4134 found. This is useful to combine several lineup functions to act in a
4135 prioritized order on a single line. However, none of the supplied
4136 lineup functions use this feature currently.
4137
4138 *** New syntactic symbol catch-clause, which is used on the "catch" and
4139 "finally" lines in try-catch constructs in C++ and Java.
4140
4141 *** New cleanup brace-catch-brace on c-cleanup-list, which does for
4142 "catch" lines what brace-elseif-brace does for "else if" lines.
4143
4144 *** The braces of Java anonymous inner classes are treated separately
4145 from the braces of other classes in auto-newline mode. Two new
4146 symbols inexpr-class-open and inexpr-class-close may be used on
4147 c-hanging-braces-alist to control the automatic newlines used for
4148 anonymous classes.
4149
4150 *** Support for the Pike language added, along with new Pike specific
4151 syntactic symbols: inlambda, lambda-intro-cont
4152
4153 *** Support for Java anonymous classes via new syntactic symbol
4154 inexpr-class. New syntactic symbol inexpr-statement for Pike
4155 support and gcc-style statements inside expressions. New lineup
4156 function c-lineup-inexpr-block.
4157
4158 *** New syntactic symbol brace-entry-open which is used in brace lists
4159 (i.e. static initializers) when a list entry starts with an open
4160 brace. These used to be recognized as brace-list-entry's.
4161 c-electric-brace also recognizes brace-entry-open braces
4162 (brace-list-entry's can no longer be electrified).
4163
4164 *** New command c-indent-line-or-region, not bound by default.
4165
4166 *** `#' is only electric when typed in the indentation of a line.
4167
4168 *** Parentheses are now electric (via the new command c-electric-paren)
4169 for auto-reindenting lines when parens are typed.
4170
4171 *** In "gnu" style, inline-open offset is now set to zero.
4172
4173 *** Uniform handling of the inclass syntactic symbol. The indentation
4174 associated with it is now always relative to the class opening brace.
4175 This means that the indentation behavior has changed in some
4176 circumstances, but only if you've put anything besides 0 on the
4177 class-open syntactic symbol (none of the default styles do that).
4178
4179 ** Gnus changes.
4180
4181 *** New functionality for using Gnus as an offline newsreader has been
4182 added. A plethora of new commands and modes have been added. See the
4183 Gnus manual for the full story.
4184
4185 *** The nndraft backend has returned, but works differently than
4186 before. All Message buffers are now also articles in the nndraft
4187 group, which is created automatically.
4188
4189 *** `gnus-alter-header-function' can now be used to alter header
4190 values.
4191
4192 *** `gnus-summary-goto-article' now accept Message-ID's.
4193
4194 *** A new Message command for deleting text in the body of a message
4195 outside the region: `C-c C-v'.
4196
4197 *** You can now post to component group in nnvirtual groups with
4198 `C-u C-c C-c'.
4199
4200 *** `nntp-rlogin-program' -- new variable to ease customization.
4201
4202 *** `C-u C-c C-c' in `gnus-article-edit-mode' will now inhibit
4203 re-highlighting of the article buffer.
4204
4205 *** New element in `gnus-boring-article-headers' -- `long-to'.
4206
4207 *** `M-i' symbolic prefix command. See the section "Symbolic
4208 Prefixes" in the Gnus manual for details.
4209
4210 *** `L' and `I' in the summary buffer now take the symbolic prefix
4211 `a' to add the score rule to the "all.SCORE" file.
4212
4213 *** `gnus-simplify-subject-functions' variable to allow greater
4214 control over simplification.
4215
4216 *** `A T' -- new command for fetching the current thread.
4217
4218 *** `/ T' -- new command for including the current thread in the
4219 limit.
4220
4221 *** `M-RET' is a new Message command for breaking cited text.
4222
4223 *** \\1-expressions are now valid in `nnmail-split-methods'.
4224
4225 *** The `custom-face-lookup' function has been removed.
4226 If you used this function in your initialization files, you must
4227 rewrite them to use `face-spec-set' instead.
4228
4229 *** Cancelling now uses the current select method. Symbolic prefix
4230 `a' forces normal posting method.
4231
4232 *** New command to translate M******** sm*rtq**t*s into proper text
4233 -- `W d'.
4234
4235 *** For easier debugging of nntp, you can set `nntp-record-commands'
4236 to a non-nil value.
4237
4238 *** nntp now uses ~/.authinfo, a .netrc-like file, for controlling
4239 where and how to send AUTHINFO to NNTP servers.
4240
4241 *** A command for editing group parameters from the summary buffer
4242 has been added.
4243
4244 *** A history of where mails have been split is available.
4245
4246 *** A new article date command has been added -- `article-date-iso8601'.
4247
4248 *** Subjects can be simplified when threading by setting
4249 `gnus-score-thread-simplify'.
4250
4251 *** A new function for citing in Message has been added --
4252 `message-cite-original-without-signature'.
4253
4254 *** `article-strip-all-blank-lines' -- new article command.
4255
4256 *** A new Message command to kill to the end of the article has
4257 been added.
4258
4259 *** A minimum adaptive score can be specified by using the
4260 `gnus-adaptive-word-minimum' variable.
4261
4262 *** The "lapsed date" article header can be kept continually
4263 updated by the `gnus-start-date-timer' command.
4264
4265 *** Web listserv archives can be read with the nnlistserv backend.
4266
4267 *** Old dejanews archives can now be read by nnweb.
4268
4269 *** `gnus-posting-styles' has been re-activated.
4270
4271 ** Changes to TeX and LaTeX mode
4272
4273 *** The new variable `tex-start-options-string' can be used to give
4274 options for the TeX run. The default value causes TeX to run in
4275 nonstopmode. For an interactive TeX run set it to nil or "".
4276
4277 *** The command `tex-feed-input' sends input to the Tex Shell. In a
4278 TeX buffer it is bound to the keys C-RET, C-c RET, and C-c C-m (some
4279 of these keys may not work on all systems). For instance, if you run
4280 TeX interactively and if the TeX run stops because of an error, you
4281 can continue it without leaving the TeX buffer by typing C-RET.
4282
4283 *** The Tex Shell Buffer is now in `compilation-shell-minor-mode'.
4284 All error-parsing commands of the Compilation major mode are available
4285 but bound to keys that don't collide with the shell. Thus you can use
4286 the Tex Shell for command line executions like a usual shell.
4287
4288 *** The commands `tex-validate-region' and `tex-validate-buffer' check
4289 the matching of braces and $'s. The errors are listed in a *Occur*
4290 buffer and you can use C-c C-c or mouse-2 to go to a particular
4291 mismatch.
4292
4293 ** Changes to RefTeX mode
4294
4295 *** The table of contents buffer can now also display labels and
4296 file boundaries in addition to sections. Use `l', `i', and `c' keys.
4297
4298 *** Labels derived from context (the section heading) are now
4299 lowercase by default. To make the label legal in LaTeX, latin-1
4300 characters will lose their accent. All Mule characters will be
4301 removed from the label.
4302
4303 *** The automatic display of cross reference information can also use
4304 a window instead of the echo area. See variable `reftex-auto-view-crossref'.
4305
4306 *** kpsewhich can be used by RefTeX to find TeX and BibTeX files. See the
4307 customization group `reftex-finding-files'.
4308
4309 *** The option `reftex-bibfile-ignore-list' has been renamed to
4310 `reftex-bibfile-ignore-regexps' and indeed can be fed with regular
4311 expressions.
4312
4313 *** Multiple Selection buffers are now hidden buffers.
4314
4315 ** New/deleted modes and packages
4316
4317 *** The package snmp-mode.el provides major modes for editing SNMP and
4318 SNMPv2 MIBs. It has entries on `auto-mode-alist'.
4319
4320 *** The package sql.el provides a major mode, M-x sql-mode, for
4321 editing SQL files, and M-x sql-interactive-mode for interacting with
4322 SQL interpreters. It has an entry on `auto-mode-alist'.
4323
4324 *** M-x highlight-changes-mode provides a minor mode displaying buffer
4325 changes with a special face.
4326
4327 *** ispell4.el has been deleted. It got in the way of ispell.el and
4328 this was hard to fix reliably. It has long been obsolete -- use
4329 Ispell 3.1 and ispell.el.
4330 \f
4331 * MS-DOS changes in Emacs 20.4
4332
4333 ** Emacs compiled for MS-DOS now supports MULE features better.
4334 This includes support for display of all ISO 8859-N character sets,
4335 conversion to and from IBM codepage encoding of non-ASCII characters,
4336 and automatic setup of the MULE environment at startup. For details,
4337 check out the section `MS-DOS and MULE' in the manual.
4338
4339 The MS-DOS installation procedure automatically configures and builds
4340 Emacs with input method support if it finds an unpacked Leim
4341 distribution when the config.bat script is run.
4342
4343 ** Formerly, the value of lpr-command did not affect printing on
4344 MS-DOS unless print-region-function was set to nil, but now it
4345 controls whether an external program is invoked or output is written
4346 directly to a printer port. Similarly, in the previous version of
4347 Emacs, the value of ps-lpr-command did not affect PostScript printing
4348 on MS-DOS unless ps-printer-name was set to something other than a
4349 string (eg. t or `pipe'), but now it controls whether an external
4350 program is used. (These changes were made so that configuration of
4351 printing variables would be almost identical across all platforms.)
4352
4353 ** In the previous version of Emacs, PostScript and non-PostScript
4354 output was piped to external programs, but because most print programs
4355 available for MS-DOS and MS-Windows cannot read data from their standard
4356 input, on those systems the data to be output is now written to a
4357 temporary file whose name is passed as the last argument to the external
4358 program.
4359
4360 An exception is made for `print', a standard program on Windows NT,
4361 and `nprint', a standard program on Novell Netware. For both of these
4362 programs, the command line is constructed in the appropriate syntax
4363 automatically, using only the value of printer-name or ps-printer-name
4364 as appropriate--the value of the relevant `-switches' variable is
4365 ignored, as both programs have no useful switches.
4366
4367 ** The value of the variable dos-printer (cf. dos-ps-printer), if it has
4368 a value, overrides the value of printer-name (cf. ps-printer-name), on
4369 MS-DOS and MS-Windows only. This has been true since version 20.3, but
4370 was not documented clearly before.
4371
4372 ** All the Emacs games now work on MS-DOS terminals.
4373 This includes Tetris and Snake.
4374 \f
4375 * Lisp changes in Emacs 20.4
4376
4377 ** New functions line-beginning-position and line-end-position
4378 return the position of the beginning or end of the current line.
4379 They both accept an optional argument, which has the same
4380 meaning as the argument to beginning-of-line or end-of-line.
4381
4382 ** find-file and allied functions now have an optional argument
4383 WILDCARD. If this is non-nil, they do wildcard processing,
4384 and visit all files that match the wildcard pattern.
4385
4386 ** Changes in the file-attributes function.
4387
4388 *** The file size returned by file-attributes may be an integer or a float.
4389 It is an integer if the size fits in a Lisp integer, float otherwise.
4390
4391 *** The inode number returned by file-attributes may be an integer (if
4392 the number fits in a Lisp integer) or a cons cell containing two
4393 integers.
4394
4395 ** The new function directory-files-and-attributes returns a list of
4396 files in a directory and their attributes. It accepts the same
4397 arguments as directory-files and has similar semantics, except that
4398 file names and attributes are returned.
4399
4400 ** The new function file-attributes-lessp is a helper function for
4401 sorting the list generated by directory-files-and-attributes. It
4402 accepts two arguments, each a list of a file name and its atttributes.
4403 It compares the file names of each according to string-lessp and
4404 returns the result.
4405
4406 ** The new function file-expand-wildcards expands a wildcard-pattern
4407 to produce a list of existing files that match the pattern.
4408
4409 ** New functions for base64 conversion:
4410
4411 The function base64-encode-region converts a part of the buffer
4412 into the base64 code used in MIME. base64-decode-region
4413 performs the opposite conversion. Line-breaking is supported
4414 optionally.
4415
4416 Functions base64-encode-string and base64-decode-string do a similar
4417 job on the text in a string. They return the value as a new string.
4418
4419 **
4420 The new function process-running-child-p
4421 will tell you if a subprocess has given control of its
4422 terminal to its own child process.
4423
4424 ** interrupt-process and such functions have a new feature:
4425 when the second argument is `lambda', they send a signal
4426 to the running child of the subshell, if any, but if the shell
4427 itself owns its terminal, no signal is sent.
4428
4429 ** There are new widget types `plist' and `alist' which can
4430 be used for customizing variables whose values are plists or alists.
4431
4432 ** easymenu.el Now understands `:key-sequence' and `:style button'.
4433 :included is an alias for :visible.
4434
4435 easy-menu-add-item now understands the values returned by
4436 easy-menu-remove-item and easy-menu-item-present-p. This can be used
4437 to move or copy menu entries.
4438
4439 ** Multibyte editing changes
4440
4441 *** The definitions of sref and char-bytes are changed. Now, sref is
4442 an alias of aref and char-bytes always returns 1. This change is to
4443 make some Emacs Lisp code which works on 20.2 and earlier also
4444 work on the latest Emacs. Such code uses a combination of sref and
4445 char-bytes in a loop typically as below:
4446 (setq char (sref str idx)
4447 idx (+ idx (char-bytes idx)))
4448 The byte-compiler now warns that this is obsolete.
4449
4450 If you want to know how many bytes a specific multibyte character
4451 (say, CH) occupies in a multibyte buffer, use this code:
4452 (charset-bytes (char-charset ch))
4453
4454 *** In multibyte mode, when you narrow a buffer to some region, and the
4455 region is preceded or followed by non-ASCII codes, inserting or
4456 deleting at the head or the end of the region may signal this error:
4457
4458 Byte combining across boundary of accessible buffer text inhibitted
4459
4460 This is to avoid some bytes being combined together into a character
4461 across the boundary.
4462
4463 *** The functions find-charset-region and find-charset-string include
4464 `unknown' in the returned list in the following cases:
4465 o The current buffer or the target string is unibyte and
4466 contains 8-bit characters.
4467 o The current buffer or the target string is multibyte and
4468 contains invalid characters.
4469
4470 *** The functions decode-coding-region and encode-coding-region remove
4471 text properties of the target region. Ideally, they should correctly
4472 preserve text properties, but for the moment, it's hard. Removing
4473 text properties is better than preserving them in a less-than-correct
4474 way.
4475
4476 *** prefer-coding-system sets EOL conversion of default coding systems.
4477 If the argument to prefer-coding-system specifies a certain type of
4478 end of line conversion, the default coding systems set by
4479 prefer-coding-system will specify that conversion type for end of line.
4480
4481 *** The new function thai-compose-string can be used to properly
4482 compose Thai characters in a string.
4483
4484 ** The primitive `define-prefix-command' now takes an optional third
4485 argument NAME, which should be a string. It supplies the menu name
4486 for the created keymap. Keymaps created in order to be displayed as
4487 menus should always use the third argument.
4488
4489 ** The meanings of optional second arguments for read-char,
4490 read-event, and read-char-exclusive are flipped. Now the second
4491 arguments are INHERIT-INPUT-METHOD. These functions use the current
4492 input method (if any) if and only if INHERIT-INPUT-METHOD is non-nil.
4493
4494 ** The new function clear-this-command-keys empties out the contents
4495 of the vector that (this-command-keys) returns. This is useful in
4496 programs that read passwords, to prevent the passwords from echoing
4497 inadvertently as part of the next command in certain cases.
4498
4499 ** The new macro `with-temp-message' displays a temporary message in
4500 the echo area, while executing some Lisp code. Like `progn', it
4501 returns the value of the last form, but it also restores the previous
4502 echo area contents.
4503
4504 (with-temp-message MESSAGE &rest BODY)
4505
4506 ** The function `require' now takes an optional third argument
4507 NOERROR. If it is non-nil, then there is no error if the
4508 requested feature cannot be loaded.
4509
4510 ** In the function modify-face, an argument of (nil) for the
4511 foreground color, background color or stipple pattern
4512 means to clear out that attribute.
4513
4514 ** The `outer-window-id' frame property of an X frame
4515 gives the window number of the outermost X window for the frame.
4516
4517 ** Temporary buffers made with with-output-to-temp-buffer are now
4518 read-only by default, and normally use the major mode Help mode
4519 unless you put them in some other non-Fundamental mode before the
4520 end of with-output-to-temp-buffer.
4521
4522 ** The new functions gap-position and gap-size return information on
4523 the gap of the current buffer.
4524
4525 ** The new functions position-bytes and byte-to-position provide a way
4526 to convert between character positions and byte positions in the
4527 current buffer.
4528
4529 ** vc.el defines two new macros, `edit-vc-file' and `with-vc-file', to
4530 facilitate working with version-controlled files from Lisp programs.
4531 These macros check out a given file automatically if needed, and check
4532 it back in after any modifications have been made.
4533 \f
4534 * Installation Changes in Emacs 20.3
4535
4536 ** The default value of load-path now includes most subdirectories of
4537 the site-specific directories /usr/local/share/emacs/site-lisp and
4538 /usr/local/share/emacs/VERSION/site-lisp, in addition to those
4539 directories themselves. Both immediate subdirectories and
4540 subdirectories multiple levels down are added to load-path.
4541
4542 Not all subdirectories are included, though. Subdirectories whose
4543 names do not start with a letter or digit are excluded.
4544 Subdirectories named RCS or CVS are excluded. Also, a subdirectory
4545 which contains a file named `.nosearch' is excluded. You can use
4546 these methods to prevent certain subdirectories from being searched.
4547
4548 Emacs finds these subdirectories and adds them to load-path when it
4549 starts up. While it would be cleaner to find the subdirectories each
4550 time Emacs loads a file, that would be much slower.
4551
4552 This feature is an incompatible change. If you have stored some Emacs
4553 Lisp files in a subdirectory of the site-lisp directory specifically
4554 to prevent them from being used, you will need to rename the
4555 subdirectory to start with a non-alphanumeric character, or create a
4556 `.nosearch' file in it, in order to continue to achieve the desired
4557 results.
4558
4559 ** Emacs no longer includes an old version of the C preprocessor from
4560 GCC. This was formerly used to help compile Emacs with C compilers
4561 that had limits on the significant length of an identifier, but in
4562 fact we stopped supporting such compilers some time ago.
4563 \f
4564 * Changes in Emacs 20.3
4565
4566 ** The new command C-x z (repeat) repeats the previous command
4567 including its argument. If you repeat the z afterward,
4568 it repeats the command additional times; thus, you can
4569 perform many repetitions with one keystroke per repetition.
4570
4571 ** Emacs now supports "selective undo" which undoes only within a
4572 specified region. To do this, set point and mark around the desired
4573 region and type C-u C-x u (or C-u C-_). You can then continue undoing
4574 further, within the same region, by repeating the ordinary undo
4575 command C-x u or C-_. This will keep undoing changes that were made
4576 within the region you originally specified, until either all of them
4577 are undone, or it encounters a change which crosses the edge of that
4578 region.
4579
4580 In Transient Mark mode, undoing when a region is active requests
4581 selective undo.
4582
4583 ** If you specify --unibyte when starting Emacs, then all buffers are
4584 unibyte, except when a Lisp program specifically creates a multibyte
4585 buffer. Setting the environment variable EMACS_UNIBYTE has the same
4586 effect. The --no-unibyte option overrides EMACS_UNIBYTE and directs
4587 Emacs to run normally in multibyte mode.
4588
4589 The option --unibyte does not affect the reading of Emacs Lisp files,
4590 though. If you want a Lisp file to be read in unibyte mode, use
4591 -*-unibyte: t;-*- on its first line. That will force Emacs to
4592 load that file in unibyte mode, regardless of how Emacs was started.
4593
4594 ** toggle-enable-multibyte-characters no longer has a key binding and
4595 no longer appears in the menu bar. We've realized that changing the
4596 enable-multibyte-characters variable in an existing buffer is
4597 something that most users not do.
4598
4599 ** You can specify a coding system to use for the next cut or paste
4600 operations through the window system with the command C-x RET X.
4601 The coding system can make a difference for communication with other
4602 applications.
4603
4604 C-x RET x specifies a coding system for all subsequent cutting and
4605 pasting operations.
4606
4607 ** You can specify the printer to use for commands that do printing by
4608 setting the variable `printer-name'. Just what a printer name looks
4609 like depends on your operating system. You can specify a different
4610 printer for the Postscript printing commands by setting
4611 `ps-printer-name'.
4612
4613 ** Emacs now supports on-the-fly spell checking by the means of a
4614 minor mode. It is called M-x flyspell-mode. You don't have to remember
4615 any other special commands to use it, and you will hardly notice it
4616 except when you make a spelling error. Flyspell works by highlighting
4617 incorrect words as soon as they are completed or as soon as the cursor
4618 hits a new word.
4619
4620 Flyspell mode works with whichever dictionary you have selected for
4621 Ispell in Emacs. In TeX mode, it understands TeX syntax so as not
4622 to be confused by TeX commands.
4623
4624 You can correct a misspelled word by editing it into something
4625 correct. You can also correct it, or accept it as correct, by
4626 clicking on the word with Mouse-2; that gives you a pop-up menu
4627 of various alternative replacements and actions.
4628
4629 Flyspell mode also proposes "automatic" corrections. M-TAB replaces
4630 the current misspelled word with a possible correction. If several
4631 corrections are made possible, M-TAB cycles through them in
4632 alphabetical order, or in order of decreasing likelihood if
4633 flyspell-sort-corrections is nil.
4634
4635 Flyspell mode also flags an error when a word is repeated, if
4636 flyspell-mark-duplications-flag is non-nil.
4637
4638 ** Changes in input method usage.
4639
4640 Now you can use arrow keys (right, left, down, up) for selecting among
4641 the alternatives just the same way as you do by C-f, C-b, C-n, and C-p
4642 respectively.
4643
4644 You can use the ENTER key to accept the current conversion.
4645
4646 If you type TAB to display a list of alternatives, you can select one
4647 of the alternatives with Mouse-2.
4648
4649 The meaning of the variable `input-method-verbose-flag' is changed so
4650 that you can set it to t, nil, `default', or `complex-only'.
4651
4652 If the value is nil, extra guidance is never given.
4653
4654 If the value is t, extra guidance is always given.
4655
4656 If the value is `complex-only', extra guidance is always given only
4657 when you are using complex input methods such as chinese-py.
4658
4659 If the value is `default' (this is the default), extra guidance is
4660 given in the following case:
4661 o When you are using a complex input method.
4662 o When you are using a simple input method but not in the minibuffer.
4663
4664 If you are using Emacs through a very slow line, setting
4665 input-method-verbose-flag to nil or to complex-only is a good choice,
4666 and if you are using an input method you are not familiar with,
4667 setting it to t is helpful.
4668
4669 The old command select-input-method is now called set-input-method.
4670
4671 In the language environment "Korean", you can use the following
4672 keys:
4673 Shift-SPC toggle-korean-input-method
4674 C-F9 quail-hangul-switch-symbol-ksc
4675 F9 quail-hangul-switch-hanja
4676 These key bindings are canceled when you switch to another language
4677 environment.
4678
4679 ** The minibuffer history of file names now records the specified file
4680 names, not the entire minibuffer input. For example, if the
4681 minibuffer starts out with /usr/foo/, you might type in /etc/passwd to
4682 get
4683
4684 /usr/foo//etc/passwd
4685
4686 which stands for the file /etc/passwd.
4687
4688 Formerly, this used to put /usr/foo//etc/passwd in the history list.
4689 Now this puts just /etc/passwd in the history list.
4690
4691 ** If you are root, Emacs sets backup-by-copying-when-mismatch to t
4692 at startup, so that saving a file will be sure to preserve
4693 its owner and group.
4694
4695 ** find-func.el can now also find the place of definition of Emacs
4696 Lisp variables in user-loaded libraries.
4697
4698 ** C-x r t (string-rectangle) now deletes the existing rectangle
4699 contents before inserting the specified string on each line.
4700
4701 ** There is a new command delete-whitespace-rectangle
4702 which deletes whitespace starting from a particular column
4703 in all the lines on a rectangle. The column is specified
4704 by the left edge of the rectangle.
4705
4706 ** You can now store a number into a register with C-u NUMBER C-x r n REG,
4707 increment it by INC with C-u INC C-x r + REG (to increment by one, omit
4708 C-u INC), and insert it in the buffer with C-x r g REG. This is useful
4709 for writing keyboard macros.
4710
4711 ** The new command M-x speedbar displays a frame in which directories,
4712 files, and tags can be displayed, manipulated, and jumped to. The
4713 frame defaults to 20 characters in width, and is the same height as
4714 the frame that it was started from. Some major modes define
4715 additional commands for the speedbar, including Rmail, GUD/GDB, and
4716 info.
4717
4718 ** query-replace-regexp is now bound to C-M-%.
4719
4720 ** In Transient Mark mode, when the region is active, M-x
4721 query-replace and the other replace commands now operate on the region
4722 contents only.
4723
4724 ** M-x write-region, when used interactively, now asks for
4725 confirmation before overwriting an existing file. When you call
4726 the function from a Lisp program, a new optional argument CONFIRM
4727 says whether to ask for confirmation in this case.
4728
4729 ** If you use find-file-literally and the file is already visited
4730 non-literally, the command asks you whether to revisit the file
4731 literally. If you say no, it signals an error.
4732
4733 ** Major modes defined with the "derived mode" feature
4734 now use the proper name for the mode hook: WHATEVER-mode-hook.
4735 Formerly they used the name WHATEVER-mode-hooks, but that is
4736 inconsistent with Emacs conventions.
4737
4738 ** shell-command-on-region (and shell-command) reports success or
4739 failure if the command produces no output.
4740
4741 ** Set focus-follows-mouse to nil if your window system or window
4742 manager does not transfer focus to another window when you just move
4743 the mouse.
4744
4745 ** mouse-menu-buffer-maxlen has been renamed to
4746 mouse-buffer-menu-maxlen to be consistent with the other related
4747 function and variable names.
4748
4749 ** The new variable auto-coding-alist specifies coding systems for
4750 reading specific files. This has higher priority than
4751 file-coding-system-alist.
4752
4753 ** If you set the variable unibyte-display-via-language-environment to
4754 t, then Emacs displays non-ASCII characters are displayed by
4755 converting them to the equivalent multibyte characters according to
4756 the current language environment. As a result, they are displayed
4757 according to the current fontset.
4758
4759 ** C-q's handling of codes in the range 0200 through 0377 is changed.
4760
4761 The codes in the range 0200 through 0237 are inserted as one byte of
4762 that code regardless of the values of nonascii-translation-table and
4763 nonascii-insert-offset.
4764
4765 For the codes in the range 0240 through 0377, if
4766 enable-multibyte-characters is non-nil and nonascii-translation-table
4767 nor nonascii-insert-offset can't convert them to valid multibyte
4768 characters, they are converted to Latin-1 characters.
4769
4770 ** If you try to find a file that is not read-accessible, you now get
4771 an error, rather than an empty buffer and a warning.
4772
4773 ** In the minibuffer history commands M-r and M-s, an upper case
4774 letter in the regular expression forces case-sensitive search.
4775
4776 ** In the *Help* buffer, cross-references to commands and variables
4777 are inferred and hyperlinked. Use C-h m in Help mode for the relevant
4778 command keys.
4779
4780 ** M-x apropos-command, with a prefix argument, no longer looks for
4781 user option variables--instead it looks for noninteractive functions.
4782
4783 Meanwhile, the command apropos-variable normally searches for
4784 user option variables; with a prefix argument, it looks at
4785 all variables that have documentation.
4786
4787 ** When you type a long line in the minibuffer, and the minibuffer
4788 shows just one line, automatically scrolling works in a special way
4789 that shows you overlap with the previous line of text. The variable
4790 minibuffer-scroll-overlap controls how many characters of overlap
4791 it should show; the default is 20.
4792
4793 Meanwhile, Resize Minibuffer mode is still available; in that mode,
4794 the minibuffer grows taller (up to a point) as needed to show the whole
4795 of your input.
4796
4797 ** The new command M-x customize-changed-options lets you customize
4798 all the options whose meanings or default values have changed in
4799 recent Emacs versions. You specify a previous Emacs version number as
4800 argument, and the command creates a customization buffer showing all
4801 the customizable options which were changed since that version.
4802 Newly added options are included as well.
4803
4804 If you don't specify a particular version number argument,
4805 then the customization buffer shows all the customizable options
4806 for which Emacs versions of changes are recorded.
4807
4808 This function is also bound to the Changed Options entry in the
4809 Customize menu.
4810
4811 ** When you run M-x grep with a prefix argument, it figures out
4812 the tag around point and puts that into the default grep command.
4813
4814 ** The new command M-* (pop-tag-mark) pops back through a history of
4815 buffer positions from which M-. or other tag-finding commands were
4816 invoked.
4817
4818 ** The new variable comment-padding specifies the number of spaces
4819 that `comment-region' will insert before the actual text of the comment.
4820 The default is 1.
4821
4822 ** In Fortran mode the characters `.', `_' and `$' now have symbol
4823 syntax, not word syntax. Fortran mode now supports `imenu' and has
4824 new commands fortran-join-line (M-^) and fortran-narrow-to-subprogram
4825 (C-x n d). M-q can be used to fill a statement or comment block
4826 sensibly.
4827
4828 ** GUD now supports jdb, the Java debugger, and pdb, the Python debugger.
4829
4830 ** If you set the variable add-log-keep-changes-together to a non-nil
4831 value, the command `C-x 4 a' will automatically notice when you make
4832 two entries in one day for one file, and combine them.
4833
4834 ** You can use the command M-x diary-mail-entries to mail yourself a
4835 reminder about upcoming diary entries. See the documentation string
4836 for a sample shell script for calling this function automatically
4837 every night.
4838
4839 ** Desktop changes
4840
4841 *** All you need to do to enable use of the Desktop package, is to set
4842 the variable desktop-enable to t with Custom.
4843
4844 *** Minor modes are now restored. Which minor modes are restored
4845 and how modes are restored is controlled by `desktop-minor-mode-table'.
4846
4847 ** There is no need to do anything special, now, to enable Gnus to
4848 read and post multi-lingual articles.
4849
4850 ** Outline mode has now support for showing hidden outlines when
4851 doing an isearch. In order for this to happen search-invisible should
4852 be set to open (the default). If an isearch match is inside a hidden
4853 outline the outline is made visible. If you continue pressing C-s and
4854 the match moves outside the formerly invisible outline, the outline is
4855 made invisible again.
4856
4857 ** Mail reading and sending changes
4858
4859 *** The Rmail e command now switches to displaying the whole header of
4860 the message before it lets you edit the message. This is so that any
4861 changes you make in the header will not be lost if you subsequently
4862 toggle.
4863
4864 *** The w command in Rmail, which writes the message body into a file,
4865 now works in the summary buffer as well. (The command to delete the
4866 summary buffer is now Q.) The default file name for the w command, if
4867 the message has no subject, is stored in the variable
4868 rmail-default-body-file.
4869
4870 *** Most of the commands and modes that operate on mail and netnews no
4871 longer depend on the value of mail-header-separator. Instead, they
4872 handle whatever separator the buffer happens to use.
4873
4874 *** If you set mail-signature to a value which is not t, nil, or a string,
4875 it should be an expression. When you send a message, this expression
4876 is evaluated to insert the signature.
4877
4878 *** The new Lisp library feedmail.el (version 8) enhances processing of
4879 outbound email messages. It works in coordination with other email
4880 handling packages (e.g., rmail, VM, gnus) and is responsible for
4881 putting final touches on messages and actually submitting them for
4882 transmission. Users of the emacs program "fakemail" might be
4883 especially interested in trying feedmail.
4884
4885 feedmail is not enabled by default. See comments at the top of
4886 feedmail.el for set-up instructions. Among the bigger features
4887 provided by feedmail are:
4888
4889 **** you can park outgoing messages into a disk-based queue and
4890 stimulate sending some or all of them later (handy for laptop users);
4891 there is also a queue for draft messages
4892
4893 **** you can get one last look at the prepped outbound message and
4894 be prompted for confirmation
4895
4896 **** does smart filling of address headers
4897
4898 **** can generate a MESSAGE-ID: line and a DATE: line; the date can be
4899 the time the message was written or the time it is being sent; this
4900 can make FCC copies more closely resemble copies that recipients get
4901
4902 **** you can specify an arbitrary function for actually transmitting
4903 the message; included in feedmail are interfaces for /bin/[r]mail,
4904 /usr/lib/sendmail, and elisp smtpmail; it's easy to write a new
4905 function for something else (10-20 lines of elisp)
4906
4907 ** Dired changes
4908
4909 *** The Dired function dired-do-toggle, which toggles marked and unmarked
4910 files, is now bound to "t" instead of "T".
4911
4912 *** dired-at-point has been added to ffap.el. It allows one to easily
4913 run Dired on the directory name at point.
4914
4915 *** Dired has a new command: %g. It searches the contents of
4916 files in the directory and marks each file that contains a match
4917 for a specified regexp.
4918
4919 ** VC Changes
4920
4921 *** New option vc-ignore-vc-files lets you turn off version control
4922 conveniently.
4923
4924 *** VC Dired has been completely rewritten. It is now much
4925 faster, especially for CVS, and works very similar to ordinary
4926 Dired.
4927
4928 VC Dired is invoked by typing C-x v d and entering the name of the
4929 directory to display. By default, VC Dired gives you a recursive
4930 listing of all files at or below the given directory which are
4931 currently locked (for CVS, all files not up-to-date are shown).
4932
4933 You can change the listing format by setting vc-dired-recurse to nil,
4934 then it shows only the given directory, and you may also set
4935 vc-dired-terse-display to nil, then it shows all files under version
4936 control plus the names of any subdirectories, so that you can type `i'
4937 on such lines to insert them manually, as in ordinary Dired.
4938
4939 All Dired commands operate normally in VC Dired, except for `v', which
4940 is redefined as the version control prefix. That means you may type
4941 `v l', `v =' etc. to invoke `vc-print-log', `vc-diff' and the like on
4942 the file named in the current Dired buffer line. `v v' invokes
4943 `vc-next-action' on this file, or on all files currently marked.
4944
4945 The new command `v t' (vc-dired-toggle-terse-mode) allows you to
4946 toggle between terse display (only locked files) and full display (all
4947 VC files plus subdirectories). There is also a special command,
4948 `* l', to mark all files currently locked.
4949
4950 Giving a prefix argument to C-x v d now does the same thing as in
4951 ordinary Dired: it allows you to supply additional options for the ls
4952 command in the minibuffer, to fine-tune VC Dired's output.
4953
4954 *** Under CVS, if you merge changes from the repository into a working
4955 file, and CVS detects conflicts, VC now offers to start an ediff
4956 session to resolve them.
4957
4958 Alternatively, you can use the new command `vc-resolve-conflicts' to
4959 resolve conflicts in a file at any time. It works in any buffer that
4960 contains conflict markers as generated by rcsmerge (which is what CVS
4961 uses as well).
4962
4963 *** You can now transfer changes between branches, using the new
4964 command vc-merge (C-x v m). It is implemented for RCS and CVS. When
4965 you invoke it in a buffer under version-control, you can specify
4966 either an entire branch or a pair of versions, and the changes on that
4967 branch or between the two versions are merged into the working file.
4968 If this results in any conflicts, they may be resolved interactively,
4969 using ediff.
4970
4971 ** Changes in Font Lock
4972
4973 *** The face and variable previously known as font-lock-reference-face
4974 are now called font-lock-constant-face to better reflect their typical
4975 use for highlighting constants and labels. (Its face properties are
4976 unchanged.) The variable font-lock-reference-face remains for now for
4977 compatibility reasons, but its value is font-lock-constant-face.
4978
4979 ** Frame name display changes
4980
4981 *** The command set-frame-name lets you set the name of the current
4982 frame. You can use the new command select-frame-by-name to select and
4983 raise a frame; this is mostly useful on character-only terminals, or
4984 when many frames are invisible or iconified.
4985
4986 *** On character-only terminal (not a window system), changing the
4987 frame name is now reflected on the mode line and in the Buffers/Frames
4988 menu.
4989
4990 ** Comint (subshell) changes
4991
4992 *** In Comint modes, the commands to kill, stop or interrupt a
4993 subjob now also kill pending input. This is for compatibility
4994 with ordinary shells, where the signal characters do this.
4995
4996 *** There are new commands in Comint mode.
4997
4998 C-c C-x fetches the "next" line from the input history;
4999 that is, the line after the last line you got.
5000 You can use this command to fetch successive lines, one by one.
5001
5002 C-c SPC accumulates lines of input. More precisely, it arranges to
5003 send the current line together with the following line, when you send
5004 the following line.
5005
5006 C-c C-a if repeated twice consecutively now moves to the process mark,
5007 which separates the pending input from the subprocess output and the
5008 previously sent input.
5009
5010 C-c M-r now runs comint-previous-matching-input-from-input;
5011 it searches for a previous command, using the current pending input
5012 as the search string.
5013
5014 *** New option compilation-scroll-output can be set to scroll
5015 automatically in compilation-mode windows.
5016
5017 ** C mode changes
5018
5019 *** Multiline macros are now handled, both as they affect indentation,
5020 and as recognized syntax. New syntactic symbol cpp-macro-cont is
5021 assigned to second and subsequent lines of a multiline macro
5022 definition.
5023
5024 *** A new style "user" which captures all non-hook-ified
5025 (i.e. top-level) .emacs file variable settings and customizations.
5026 Style "cc-mode" is an alias for "user" and is deprecated. "gnu"
5027 style is still the default however.
5028
5029 *** "java" style now conforms to Sun's JDK coding style.
5030
5031 *** There are new commands c-beginning-of-defun, c-end-of-defun which
5032 are alternatives which you could bind to C-M-a and C-M-e if you prefer
5033 them. They do not have key bindings by default.
5034
5035 *** New and improved implementations of M-a (c-beginning-of-statement)
5036 and M-e (c-end-of-statement).
5037
5038 *** C++ namespace blocks are supported, with new syntactic symbols
5039 namespace-open, namespace-close, and innamespace.
5040
5041 *** File local variable settings of c-file-style and c-file-offsets
5042 makes the style variables local to that buffer only.
5043
5044 *** New indentation functions c-lineup-close-paren,
5045 c-indent-one-line-block, c-lineup-dont-change.
5046
5047 *** Improvements (hopefully!) to the way CC Mode is loaded. You
5048 should now be able to do a (require 'cc-mode) to get the entire
5049 package loaded properly for customization in your .emacs file. A new
5050 variable c-initialize-on-load controls this and is t by default.
5051
5052 ** Changes to hippie-expand.
5053
5054 *** New customization variable `hippie-expand-dabbrev-skip-space'. If
5055 non-nil, trailing spaces may be included in the abbreviation to search for,
5056 which then gives the same behavior as the original `dabbrev-expand'.
5057
5058 *** New customization variable `hippie-expand-dabbrev-as-symbol'. If
5059 non-nil, characters of syntax '_' is considered part of the word when
5060 expanding dynamically.
5061
5062 *** New customization variable `hippie-expand-no-restriction'. If
5063 non-nil, narrowed buffers are widened before they are searched.
5064
5065 *** New customization variable `hippie-expand-only-buffers'. If
5066 non-empty, buffers searched are restricted to the types specified in
5067 this list. Useful for example when constructing new special-purpose
5068 expansion functions with `make-hippie-expand-function'.
5069
5070 *** Text properties of the expansion are no longer copied.
5071
5072 ** Changes in BibTeX mode.
5073
5074 *** Any titleword matching a regexp in the new variable
5075 bibtex-autokey-titleword-ignore (case sensitive) is ignored during
5076 automatic key generation. This replaces variable
5077 bibtex-autokey-titleword-first-ignore, which only checked for matches
5078 against the first word in the title.
5079
5080 *** Autokey generation now uses all words from the title, not just
5081 capitalized words. To avoid conflicts with existing customizations,
5082 bibtex-autokey-titleword-ignore is set up such that words starting with
5083 lowerkey characters will still be ignored. Thus, if you want to use
5084 lowercase words from the title, you will have to overwrite the
5085 bibtex-autokey-titleword-ignore standard setting.
5086
5087 *** Case conversion of names and title words for automatic key
5088 generation is more flexible. Variable bibtex-autokey-preserve-case is
5089 replaced by bibtex-autokey-titleword-case-convert and
5090 bibtex-autokey-name-case-convert.
5091
5092 ** Changes in vcursor.el.
5093
5094 *** Support for character terminals is available: there is a new keymap
5095 and the vcursor will appear as an arrow between buffer text. A
5096 variable `vcursor-interpret-input' allows input from the vcursor to be
5097 entered exactly as if typed. Numerous functions, including
5098 `vcursor-compare-windows', have been rewritten to improve consistency
5099 in the selection of windows and corresponding keymaps.
5100
5101 *** vcursor options can now be altered with M-x customize under the
5102 Editing group once the package is loaded.
5103
5104 *** Loading vcursor now does not define keys by default, as this is
5105 generally a bad side effect. Use M-x customize to set
5106 vcursor-key-bindings to t to restore the old behaviour.
5107
5108 *** vcursor-auto-disable can be `copy', which turns off copying from the
5109 vcursor, but doesn't disable it, after any non-vcursor command.
5110
5111 ** Ispell changes.
5112
5113 *** You can now spell check comments and strings in the current
5114 buffer with M-x ispell-comments-and-strings. Comments and strings
5115 are identified by syntax tables in effect.
5116
5117 *** Generic region skipping implemented.
5118 A single buffer can be broken into a number of regions where text will
5119 and will not be checked. The definitions of the regions can be user
5120 defined. New applications and improvements made available by this
5121 include:
5122
5123 o URLs are automatically skipped
5124 o EMail message checking is vastly improved.
5125
5126 *** Ispell can highlight the erroneous word even on non-window terminals.
5127
5128 ** Changes to RefTeX mode
5129
5130 RefTeX has been updated in order to make it more usable with very
5131 large projects (like a several volume math book). The parser has been
5132 re-written from scratch. To get maximum speed from RefTeX, check the
5133 section `Optimizations' in the manual.
5134
5135 *** New recursive parser.
5136
5137 The old version of RefTeX created a single large buffer containing the
5138 entire multifile document in order to parse the document. The new
5139 recursive parser scans the individual files.
5140
5141 *** Parsing only part of a document.
5142
5143 Reparsing of changed document parts can now be made faster by enabling
5144 partial scans. To use this feature, read the documentation string of
5145 the variable `reftex-enable-partial-scans' and set the variable to t.
5146
5147 (setq reftex-enable-partial-scans t)
5148
5149 *** Storing parsing information in a file.
5150
5151 This can improve startup times considerably. To turn it on, use
5152
5153 (setq reftex-save-parse-info t)
5154
5155 *** Using multiple selection buffers
5156
5157 If the creation of label selection buffers is too slow (this happens
5158 for large documents), you can reuse these buffers by setting
5159
5160 (setq reftex-use-multiple-selection-buffers t)
5161
5162 *** References to external documents.
5163
5164 The LaTeX package `xr' allows to cross-reference labels in external
5165 documents. RefTeX can provide information about the external
5166 documents as well. To use this feature, set up the \externaldocument
5167 macros required by the `xr' package and rescan the document with
5168 RefTeX. The external labels can then be accessed with the `x' key in
5169 the selection buffer provided by `reftex-reference' (bound to `C-c )').
5170 The `x' key also works in the table of contents buffer.
5171
5172 *** Many more labeled LaTeX environments are recognized by default.
5173
5174 The builtin command list now covers all the standard LaTeX commands,
5175 and all of the major packages included in the LaTeX distribution.
5176
5177 Also, RefTeX now understands the \appendix macro and changes
5178 the enumeration of sections in the *toc* buffer accordingly.
5179
5180 *** Mouse support for selection and *toc* buffers
5181
5182 The mouse can now be used to select items in the selection and *toc*
5183 buffers. See also the new option `reftex-highlight-selection'.
5184
5185 *** New keymaps for selection and table of contents modes.
5186
5187 The selection processes for labels and citation keys, and the table of
5188 contents buffer now have their own keymaps: `reftex-select-label-map',
5189 `reftex-select-bib-map', `reftex-toc-map'. The selection processes
5190 have a number of new keys predefined. In particular, TAB lets you
5191 enter a label with completion. Check the on-the-fly help (press `?'
5192 at the selection prompt) or read the Info documentation to find out
5193 more.
5194
5195 *** Support for the varioref package
5196
5197 The `v' key in the label selection buffer toggles \ref versus \vref.
5198
5199 *** New hooks
5200
5201 Three new hooks can be used to redefine the way labels, references,
5202 and citations are created. These hooks are
5203 `reftex-format-label-function', `reftex-format-ref-function',
5204 `reftex-format-cite-function'.
5205
5206 *** Citations outside LaTeX
5207
5208 The command `reftex-citation' may also be used outside LaTeX (e.g. in
5209 a mail buffer). See the Info documentation for details.
5210
5211 *** Short context is no longer fontified.
5212
5213 The short context in the label menu no longer copies the
5214 fontification from the text in the buffer. If you prefer it to be
5215 fontified, use
5216
5217 (setq reftex-refontify-context t)
5218
5219 ** file-cache-minibuffer-complete now accepts a prefix argument.
5220 With a prefix argument, it does not try to do completion of
5221 the file name within its directory; it only checks for other
5222 directories that contain the same file name.
5223
5224 Thus, given the file name Makefile, and assuming that a file
5225 Makefile.in exists in the same directory, ordinary
5226 file-cache-minibuffer-complete will try to complete Makefile to
5227 Makefile.in and will therefore never look for other directories that
5228 have Makefile. A prefix argument tells it not to look for longer
5229 names such as Makefile.in, so that instead it will look for other
5230 directories--just as if the name were already complete in its present
5231 directory.
5232
5233 ** New modes and packages
5234
5235 *** There is a new alternative major mode for Perl, Cperl mode.
5236 It has many more features than Perl mode, and some people prefer
5237 it, but some do not.
5238
5239 *** There is a new major mode, M-x vhdl-mode, for editing files of VHDL
5240 code.
5241
5242 *** M-x which-function-mode enables a minor mode that displays the
5243 current function name continuously in the mode line, as you move
5244 around in a buffer.
5245
5246 Which Function mode is effective in major modes which support Imenu.
5247
5248 *** Gametree is a major mode for editing game analysis trees. The author
5249 uses it for keeping notes about his postal Chess games, but it should
5250 be helpful for other two-player games as well, as long as they have an
5251 established system of notation similar to Chess.
5252
5253 *** The new minor mode checkdoc-minor-mode provides Emacs Lisp
5254 documentation string checking for style and spelling. The style
5255 guidelines are found in the Emacs Lisp programming manual.
5256
5257 *** The net-utils package makes some common networking features
5258 available in Emacs. Some of these functions are wrappers around
5259 system utilities (ping, nslookup, etc); others are implementations of
5260 simple protocols (finger, whois) in Emacs Lisp. There are also
5261 functions to make simple connections to TCP/IP ports for debugging and
5262 the like.
5263
5264 *** highlight-changes-mode is a minor mode that uses colors to
5265 identify recently changed parts of the buffer text.
5266
5267 *** The new package `midnight' lets you specify things to be done
5268 within Emacs at midnight--by default, kill buffers that you have not
5269 used in a considerable time. To use this feature, customize
5270 the user option `midnight-mode' to t.
5271
5272 *** The file generic-x.el defines a number of simple major modes.
5273
5274 apache-generic-mode: For Apache and NCSA httpd configuration files
5275 samba-generic-mode: Samba configuration files
5276 fvwm-generic-mode: For fvwm initialization files
5277 x-resource-generic-mode: For X resource files
5278 hosts-generic-mode: For hosts files (.rhosts, /etc/hosts, etc)
5279 mailagent-rules-generic-mode: For mailagent .rules files
5280 javascript-generic-mode: For JavaScript files
5281 vrml-generic-mode: For VRML files
5282 java-manifest-generic-mode: For Java MANIFEST files
5283 java-properties-generic-mode: For Java property files
5284 mailrc-generic-mode: For .mailrc files
5285
5286 Platform-specific modes:
5287
5288 prototype-generic-mode: For Solaris/Sys V prototype files
5289 pkginfo-generic-mode: For Solaris/Sys V pkginfo files
5290 alias-generic-mode: For C shell alias files
5291 inf-generic-mode: For MS-Windows INF files
5292 ini-generic-mode: For MS-Windows INI files
5293 reg-generic-mode: For MS-Windows Registry files
5294 bat-generic-mode: For MS-Windows BAT scripts
5295 rc-generic-mode: For MS-Windows Resource files
5296 rul-generic-mode: For InstallShield scripts
5297 \f
5298 * Lisp changes in Emacs 20.3 since the Emacs Lisp Manual was published
5299
5300 ** If you want a Lisp file to be read in unibyte mode,
5301 use -*-unibyte: t;-*- on its first line.
5302 That will force Emacs to read that file in unibyte mode.
5303 Otherwise, the file will be loaded and byte-compiled in multibyte mode.
5304
5305 Thus, each lisp file is read in a consistent way regardless of whether
5306 you started Emacs with --unibyte, so that a Lisp program gives
5307 consistent results regardless of how Emacs was started.
5308
5309 ** The new function assoc-default is useful for searching an alist,
5310 and using a default value if the key is not found there. You can
5311 specify a comparison predicate, so this function is useful for
5312 searching comparing a string against an alist of regular expressions.
5313
5314 ** The functions unibyte-char-to-multibyte and
5315 multibyte-char-to-unibyte convert between unibyte and multibyte
5316 character codes, in a way that is appropriate for the current language
5317 environment.
5318
5319 ** The functions read-event, read-char and read-char-exclusive now
5320 take two optional arguments. PROMPT, if non-nil, specifies a prompt
5321 string. SUPPRESS-INPUT-METHOD, if non-nil, says to disable the
5322 current input method for reading this one event.
5323
5324 ** Two new variables print-escape-nonascii and print-escape-multibyte
5325 now control whether to output certain characters as
5326 backslash-sequences. print-escape-nonascii applies to single-byte
5327 non-ASCII characters; print-escape-multibyte applies to multibyte
5328 characters. Both of these variables are used only when printing
5329 in readable fashion (prin1 uses them, princ does not).
5330 \f
5331 * Lisp changes in Emacs 20.3 before the Emacs Lisp Manual was published
5332
5333 ** Compiled Emacs Lisp files made with the modified "MBSK" version
5334 of Emacs 20.2 do not work in Emacs 20.3.
5335
5336 ** Buffer positions are now measured in characters, as they were
5337 in Emacs 19 and before. This means that (forward-char 1)
5338 always increases point by 1.
5339
5340 The function chars-in-region now just subtracts its arguments. It is
5341 considered obsolete. The function char-boundary-p has been deleted.
5342
5343 See below for additional changes relating to multibyte characters.
5344
5345 ** defcustom, defface and defgroup now accept the keyword `:version'.
5346 Use this to specify in which version of Emacs a certain variable's
5347 default value changed. For example,
5348
5349 (defcustom foo-max 34 "*Maximum number of foo's allowed."
5350 :type 'integer
5351 :group 'foo
5352 :version "20.3")
5353
5354 (defgroup foo-group nil "The foo group."
5355 :version "20.3")
5356
5357 If an entire new group is added or the variables in it have the
5358 default values changed, then just add a `:version' to that group. It
5359 is recommended that new packages added to the distribution contain a
5360 `:version' in the top level group.
5361
5362 This information is used to control the customize-changed-options command.
5363
5364 ** It is now an error to change the value of a symbol whose name
5365 starts with a colon--if it is interned in the standard obarray.
5366
5367 However, setting such a symbol to its proper value, which is that
5368 symbol itself, is not an error. This is for the sake of programs that
5369 support previous Emacs versions by explicitly setting these variables
5370 to themselves.
5371
5372 If you set the variable keyword-symbols-constant-flag to nil,
5373 this error is suppressed, and you can set these symbols to any
5374 values whatever.
5375
5376 ** There is a new debugger command, R.
5377 It evaluates an expression like e, but saves the result
5378 in the buffer *Debugger-record*.
5379
5380 ** Frame-local variables.
5381
5382 You can now make a variable local to various frames. To do this, call
5383 the function make-variable-frame-local; this enables frames to have
5384 local bindings for that variable.
5385
5386 These frame-local bindings are actually frame parameters: you create a
5387 frame-local binding in a specific frame by calling
5388 modify-frame-parameters and specifying the variable name as the
5389 parameter name.
5390
5391 Buffer-local bindings take precedence over frame-local bindings.
5392 Thus, if the current buffer has a buffer-local binding, that binding is
5393 active; otherwise, if the selected frame has a frame-local binding,
5394 that binding is active; otherwise, the default binding is active.
5395
5396 It would not be hard to implement window-local bindings, but it is not
5397 clear that this would be very useful; windows tend to come and go in a
5398 very transitory fashion, so that trying to produce any specific effect
5399 through a window-local binding would not be very robust.
5400
5401 ** `sregexq' and `sregex' are two new functions for constructing
5402 "symbolic regular expressions." These are Lisp expressions that, when
5403 evaluated, yield conventional string-based regexps. The symbolic form
5404 makes it easier to construct, read, and maintain complex patterns.
5405 See the documentation in sregex.el.
5406
5407 ** parse-partial-sexp's return value has an additional element which
5408 is used to pass information along if you pass it to another call to
5409 parse-partial-sexp, starting its scan where the first call ended.
5410 The contents of this field are not yet finalized.
5411
5412 ** eval-region now accepts a fourth optional argument READ-FUNCTION.
5413 If it is non-nil, that function is used instead of `read'.
5414
5415 ** unload-feature by default removes the feature's functions from
5416 known hooks to avoid trouble, but a package providing FEATURE can
5417 define a hook FEATURE-unload-hook to be run by unload-feature instead.
5418
5419 ** read-from-minibuffer no longer returns the argument DEFAULT-VALUE
5420 when the user enters empty input. It now returns the null string, as
5421 it did in Emacs 19. The default value is made available in the
5422 history via M-n, but it is not applied here as a default.
5423
5424 The other, more specialized minibuffer-reading functions continue to
5425 return the default value (not the null string) when the user enters
5426 empty input.
5427
5428 ** The new variable read-buffer-function controls which routine to use
5429 for selecting buffers. For example, if you set this variable to
5430 `iswitchb-read-buffer', iswitchb will be used to read buffer names.
5431 Other functions can also be used if they accept the same arguments as
5432 `read-buffer' and return the selected buffer name as a string.
5433
5434 ** The new function read-passwd reads a password from the terminal,
5435 echoing a period for each character typed. It takes three arguments:
5436 a prompt string, a flag which says "read it twice to make sure", and a
5437 default password to use if the user enters nothing.
5438
5439 ** The variable fill-nobreak-predicate gives major modes a way to
5440 specify not to break a line at certain places. Its value is a
5441 function which is called with no arguments, with point located at the
5442 place where a break is being considered. If the function returns
5443 non-nil, then the line won't be broken there.
5444
5445 ** window-end now takes an optional second argument, UPDATE.
5446 If this is non-nil, then the function always returns an accurate
5447 up-to-date value for the buffer position corresponding to the
5448 end of the window, even if this requires computation.
5449
5450 ** other-buffer now takes an optional argument FRAME
5451 which specifies which frame's buffer list to use.
5452 If it is nil, that means use the selected frame's buffer list.
5453
5454 ** The new variable buffer-display-time, always local in every buffer,
5455 holds the value of (current-time) as of the last time that a window
5456 was directed to display this buffer.
5457
5458 ** It is now meaningful to compare two window-configuration objects
5459 with `equal'. Two window-configuration objects are equal if they
5460 describe equivalent arrangements of windows, in the same frame--in
5461 other words, if they would give the same results if passed to
5462 set-window-configuration.
5463
5464 ** compare-window-configurations is a new function that compares two
5465 window configurations loosely. It ignores differences in saved buffer
5466 positions and scrolling, and considers only the structure and sizes of
5467 windows and the choice of buffers to display.
5468
5469 ** The variable minor-mode-overriding-map-alist allows major modes to
5470 override the key bindings of a minor mode. The elements of this alist
5471 look like the elements of minor-mode-map-alist: (VARIABLE . KEYMAP).
5472
5473 If the VARIABLE in an element of minor-mode-overriding-map-alist has a
5474 non-nil value, the paired KEYMAP is active, and totally overrides the
5475 map (if any) specified for the same variable in minor-mode-map-alist.
5476
5477 minor-mode-overriding-map-alist is automatically local in all buffers,
5478 and it is meant to be set by major modes.
5479
5480 ** The function match-string-no-properties is like match-string
5481 except that it discards all text properties from the result.
5482
5483 ** The function load-average now accepts an optional argument
5484 USE-FLOATS. If it is non-nil, the load average values are returned as
5485 floating point numbers, rather than as integers to be divided by 100.
5486
5487 ** The new variable temporary-file-directory specifies the directory
5488 to use for creating temporary files. The default value is determined
5489 in a reasonable way for your operating system; on GNU and Unix systems
5490 it is based on the TMP and TMPDIR environment variables.
5491
5492 ** Menu changes
5493
5494 *** easymenu.el now uses the new menu item format and supports the
5495 keywords :visible and :filter. The existing keyword :keys is now
5496 better supported.
5497
5498 The variable `easy-menu-precalculate-equivalent-keybindings' controls
5499 a new feature which calculates keyboard equivalents for the menu when
5500 you define the menu. The default is t. If you rarely use menus, you
5501 can set the variable to nil to disable this precalculation feature;
5502 then the calculation is done only if you use the menu bar.
5503
5504 *** A new format for menu items is supported.
5505
5506 In a keymap, a key binding that has the format
5507 (STRING . REAL-BINDING) or (STRING HELP-STRING . REAL-BINDING)
5508 defines a menu item. Now a menu item definition may also be a list that
5509 starts with the symbol `menu-item'.
5510
5511 The format is:
5512 (menu-item ITEM-NAME) or
5513 (menu-item ITEM-NAME REAL-BINDING . ITEM-PROPERTY-LIST)
5514 where ITEM-NAME is an expression which evaluates to the menu item
5515 string, and ITEM-PROPERTY-LIST has the form of a property list.
5516 The supported properties include
5517
5518 :enable FORM Evaluate FORM to determine whether the
5519 item is enabled.
5520 :visible FORM Evaluate FORM to determine whether the
5521 item should appear in the menu.
5522 :filter FILTER-FN
5523 FILTER-FN is a function of one argument,
5524 which will be REAL-BINDING.
5525 It should return a binding to use instead.
5526 :keys DESCRIPTION
5527 DESCRIPTION is a string that describes an equivalent keyboard
5528 binding for for REAL-BINDING. DESCRIPTION is expanded with
5529 `substitute-command-keys' before it is used.
5530 :key-sequence KEY-SEQUENCE
5531 KEY-SEQUENCE is a key-sequence for an equivalent
5532 keyboard binding.
5533 :key-sequence nil
5534 This means that the command normally has no
5535 keyboard equivalent.
5536 :help HELP HELP is the extra help string (not currently used).
5537 :button (TYPE . SELECTED)
5538 TYPE is :toggle or :radio.
5539 SELECTED is a form, to be evaluated, and its
5540 value says whether this button is currently selected.
5541
5542 Buttons are at the moment only simulated by prefixes in the menu.
5543 Eventually ordinary X-buttons may be supported.
5544
5545 (menu-item ITEM-NAME) defines unselectable item.
5546
5547 ** New event types
5548
5549 *** The new event type `mouse-wheel' is generated by a wheel on a
5550 mouse (such as the MS Intellimouse). The event contains a delta that
5551 corresponds to the amount and direction that the wheel is rotated,
5552 which is typically used to implement a scroll or zoom. The format is:
5553
5554 (mouse-wheel POSITION DELTA)
5555
5556 where POSITION is a list describing the position of the event in the
5557 same format as a mouse-click event, and DELTA is a signed number
5558 indicating the number of increments by which the wheel was rotated. A
5559 negative DELTA indicates that the wheel was rotated backwards, towards
5560 the user, and a positive DELTA indicates that the wheel was rotated
5561 forward, away from the user.
5562
5563 As of now, this event type is generated only on MS Windows.
5564
5565 *** The new event type `drag-n-drop' is generated when a group of
5566 files is selected in an application outside of Emacs, and then dragged
5567 and dropped onto an Emacs frame. The event contains a list of
5568 filenames that were dragged and dropped, which are then typically
5569 loaded into Emacs. The format is:
5570
5571 (drag-n-drop POSITION FILES)
5572
5573 where POSITION is a list describing the position of the event in the
5574 same format as a mouse-click event, and FILES is the list of filenames
5575 that were dragged and dropped.
5576
5577 As of now, this event type is generated only on MS Windows.
5578
5579 ** Changes relating to multibyte characters.
5580
5581 *** The variable enable-multibyte-characters is now read-only;
5582 any attempt to set it directly signals an error. The only way
5583 to change this value in an existing buffer is with set-buffer-multibyte.
5584
5585 *** In a string constant, `\ ' now stands for "nothing at all". You
5586 can use it to terminate a hex escape which is followed by a character
5587 that could otherwise be read as part of the hex escape.
5588
5589 *** String indices are now measured in characters, as they were
5590 in Emacs 19 and before.
5591
5592 The function chars-in-string has been deleted.
5593 The function concat-chars has been renamed to `string'.
5594
5595 *** The function set-buffer-multibyte sets the flag in the current
5596 buffer that says whether the buffer uses multibyte representation or
5597 unibyte representation. If the argument is nil, it selects unibyte
5598 representation. Otherwise it selects multibyte representation.
5599
5600 This function does not change the contents of the buffer, viewed
5601 as a sequence of bytes. However, it does change the contents
5602 viewed as characters; a sequence of two bytes which is treated as
5603 one character when the buffer uses multibyte representation
5604 will count as two characters using unibyte representation.
5605
5606 This function sets enable-multibyte-characters to record which
5607 representation is in use. It also adjusts various data in the buffer
5608 (including its markers, overlays and text properties) so that they are
5609 consistent with the new representation.
5610
5611 *** string-make-multibyte takes a string and converts it to multibyte
5612 representation. Most of the time, you don't need to care
5613 about the representation, because Emacs converts when necessary;
5614 however, it makes a difference when you compare strings.
5615
5616 The conversion of non-ASCII characters works by adding the value of
5617 nonascii-insert-offset to each character, or by translating them
5618 using the table nonascii-translation-table.
5619
5620 *** string-make-unibyte takes a string and converts it to unibyte
5621 representation. Most of the time, you don't need to care about the
5622 representation, but it makes a difference when you compare strings.
5623
5624 The conversion from multibyte to unibyte representation
5625 loses information; the only time Emacs performs it automatically
5626 is when inserting a multibyte string into a unibyte buffer.
5627
5628 *** string-as-multibyte takes a string, and returns another string
5629 which contains the same bytes, but treats them as multibyte.
5630
5631 *** string-as-unibyte takes a string, and returns another string
5632 which contains the same bytes, but treats them as unibyte.
5633
5634 *** The new function compare-strings lets you compare
5635 portions of two strings. Unibyte strings are converted to multibyte,
5636 so that a unibyte string can match a multibyte string.
5637 You can specify whether to ignore case or not.
5638
5639 *** assoc-ignore-case now uses compare-strings so that
5640 it can treat unibyte and multibyte strings as equal.
5641
5642 *** Regular expression operations and buffer string searches now
5643 convert the search pattern to multibyte or unibyte to accord with the
5644 buffer or string being searched.
5645
5646 One consequence is that you cannot always use \200-\377 inside of
5647 [...] to match all non-ASCII characters. This does still work when
5648 searching or matching a unibyte buffer or string, but not when
5649 searching or matching a multibyte string. Unfortunately, there is no
5650 obvious choice of syntax to use within [...] for that job. But, what
5651 you want is just to match all non-ASCII characters, the regular
5652 expression [^\0-\177] works for it.
5653
5654 *** Structure of coding system changed.
5655
5656 All coding systems (including aliases and subsidiaries) are named
5657 by symbols; the symbol's `coding-system' property is a vector
5658 which defines the coding system. Aliases share the same vector
5659 as the principal name, so that altering the contents of this
5660 vector affects the principal name and its aliases. You can define
5661 your own alias name of a coding system by the function
5662 define-coding-system-alias.
5663
5664 The coding system definition includes a property list of its own. Use
5665 the new functions `coding-system-get' and `coding-system-put' to
5666 access such coding system properties as post-read-conversion,
5667 pre-write-conversion, character-translation-table-for-decode,
5668 character-translation-table-for-encode, mime-charset, and
5669 safe-charsets. For instance, (coding-system-get 'iso-latin-1
5670 'mime-charset) gives the corresponding MIME-charset parameter
5671 `iso-8859-1'.
5672
5673 Among the coding system properties listed above, safe-charsets is new.
5674 The value of this property is a list of character sets which this
5675 coding system can correctly encode and decode. For instance:
5676 (coding-system-get 'iso-latin-1 'safe-charsets) => (ascii latin-iso8859-1)
5677
5678 Here, "correctly encode" means that the encoded character sets can
5679 also be handled safely by systems other than Emacs as far as they
5680 are capable of that coding system. Though, Emacs itself can encode
5681 the other character sets and read it back correctly.
5682
5683 *** The new function select-safe-coding-system can be used to find a
5684 proper coding system for encoding the specified region or string.
5685 This function requires a user interaction.
5686
5687 *** The new functions find-coding-systems-region and
5688 find-coding-systems-string are helper functions used by
5689 select-safe-coding-system. They return a list of all proper coding
5690 systems to encode a text in some region or string. If you don't want
5691 a user interaction, use one of these functions instead of
5692 select-safe-coding-system.
5693
5694 *** The explicit encoding and decoding functions, such as
5695 decode-coding-region and encode-coding-string, now set
5696 last-coding-system-used to reflect the actual way encoding or decoding
5697 was done.
5698
5699 *** The new function detect-coding-with-language-environment can be
5700 used to detect a coding system of text according to priorities of
5701 coding systems used by some specific language environment.
5702
5703 *** The functions detect-coding-region and detect-coding-string always
5704 return a list if the arg HIGHEST is nil. Thus, if only ASCII
5705 characters are found, they now return a list of single element
5706 `undecided' or its subsidiaries.
5707
5708 *** The new functions coding-system-change-eol-conversion and
5709 coding-system-change-text-conversion can be used to get a different
5710 coding system than what specified only in how end-of-line or text is
5711 converted.
5712
5713 *** The new function set-selection-coding-system can be used to set a
5714 coding system for communicating with other X clients.
5715
5716 *** The function `map-char-table' now passes as argument only valid
5717 character codes, plus generic characters that stand for entire
5718 character sets or entire subrows of a character set. In other words,
5719 each time `map-char-table' calls its FUNCTION argument, the key value
5720 either will be a valid individual character code, or will stand for a
5721 range of characters.
5722
5723 *** The new function `char-valid-p' can be used for checking whether a
5724 Lisp object is a valid character code or not.
5725
5726 *** The new function `charset-after' returns a charset of a character
5727 in the current buffer at position POS.
5728
5729 *** Input methods are now implemented using the variable
5730 input-method-function. If this is non-nil, its value should be a
5731 function; then, whenever Emacs reads an input event that is a printing
5732 character with no modifier bits, it calls that function, passing the
5733 event as an argument. Often this function will read more input, first
5734 binding input-method-function to nil.
5735
5736 The return value should be a list of the events resulting from input
5737 method processing. These events will be processed sequentially as
5738 input, before resorting to unread-command-events. Events returned by
5739 the input method function are not passed to the input method function,
5740 not even if they are printing characters with no modifier bits.
5741
5742 The input method function is not called when reading the second and
5743 subsequent events of a key sequence.
5744
5745 *** You can customize any language environment by using
5746 set-language-environment-hook and exit-language-environment-hook.
5747
5748 The hook `exit-language-environment-hook' should be used to undo
5749 customizations that you made with set-language-environment-hook. For
5750 instance, if you set up a special key binding for a specific language
5751 environment by set-language-environment-hook, you should set up
5752 exit-language-environment-hook to restore the normal key binding.
5753 \f
5754 * Changes in Emacs 20.1
5755
5756 ** Emacs has a new facility for customization of its many user
5757 options. It is called M-x customize. With this facility you can look
5758 at the many user options in an organized way; they are grouped into a
5759 tree structure.
5760
5761 M-x customize also knows what sorts of values are legitimate for each
5762 user option and ensures that you don't use invalid values.
5763
5764 With M-x customize, you can set options either for the present Emacs
5765 session or permanently. (Permanent settings are stored automatically
5766 in your .emacs file.)
5767
5768 ** Scroll bars are now on the left side of the window.
5769 You can change this with M-x customize-option scroll-bar-mode.
5770
5771 ** The mode line no longer includes the string `Emacs'.
5772 This makes more space in the mode line for other information.
5773
5774 ** When you select a region with the mouse, it is highlighted
5775 immediately afterward. At that time, if you type the DELETE key, it
5776 kills the region.
5777
5778 The BACKSPACE key, and the ASCII character DEL, do not do this; they
5779 delete the character before point, as usual.
5780
5781 ** In an incremental search the whole current match is highlighted
5782 on terminals which support this. (You can disable this feature
5783 by setting search-highlight to nil.)
5784
5785 ** In the minibuffer, in some cases, you can now use M-n to
5786 insert the default value into the minibuffer as text. In effect,
5787 the default value (if the minibuffer routines know it) is tacked
5788 onto the history "in the future". (The more normal use of the
5789 history list is to use M-p to insert minibuffer input used in the
5790 past.)
5791
5792 ** In Text mode, now only blank lines separate paragraphs.
5793 This makes it possible to get the full benefit of Adaptive Fill mode
5794 in Text mode, and other modes derived from it (such as Mail mode).
5795 TAB in Text mode now runs the command indent-relative; this
5796 makes a practical difference only when you use indented paragraphs.
5797
5798 As a result, the old Indented Text mode is now identical to Text mode,
5799 and is an alias for it.
5800
5801 If you want spaces at the beginning of a line to start a paragraph,
5802 use the new mode, Paragraph Indent Text mode.
5803
5804 ** Scrolling changes
5805
5806 *** Scroll commands to scroll a whole screen now preserve the screen
5807 position of the cursor, if scroll-preserve-screen-position is non-nil.
5808
5809 In this mode, if you scroll several screens back and forth, finishing
5810 on the same screen where you started, the cursor goes back to the line
5811 where it started.
5812
5813 *** If you set scroll-conservatively to a small number, then when you
5814 move point a short distance off the screen, Emacs will scroll the
5815 screen just far enough to bring point back on screen, provided that
5816 does not exceed `scroll-conservatively' lines.
5817
5818 *** The new variable scroll-margin says how close point can come to the
5819 top or bottom of a window. It is a number of screen lines; if point
5820 comes within that many lines of the top or bottom of the window, Emacs
5821 recenters the window.
5822
5823 ** International character set support (MULE)
5824
5825 Emacs now supports a wide variety of international character sets,
5826 including European variants of the Latin alphabet, as well as Chinese,
5827 Devanagari (Hindi and Marathi), Ethiopian, Greek, IPA, Japanese,
5828 Korean, Lao, Russian, Thai, Tibetan, and Vietnamese scripts. These
5829 features have been merged from the modified version of Emacs known as
5830 MULE (for "MULti-lingual Enhancement to GNU Emacs")
5831
5832 Users of these scripts have established many more-or-less standard
5833 coding systems for storing files. Emacs uses a single multibyte
5834 character encoding within Emacs buffers; it can translate from a wide
5835 variety of coding systems when reading a file and can translate back
5836 into any of these coding systems when saving a file.
5837
5838 Keyboards, even in the countries where these character sets are used,
5839 generally don't have keys for all the characters in them. So Emacs
5840 supports various "input methods", typically one for each script or
5841 language, to make it possible to type them.
5842
5843 The Emacs internal multibyte encoding represents a non-ASCII
5844 character as a sequence of bytes in the range 0200 through 0377.
5845
5846 The new prefix key C-x RET is used for commands that pertain
5847 to multibyte characters, coding systems, and input methods.
5848
5849 You can disable multibyte character support as follows:
5850
5851 (setq-default enable-multibyte-characters nil)
5852
5853 Calling the function standard-display-european turns off multibyte
5854 characters, unless you specify a non-nil value for the second
5855 argument, AUTO. This provides compatibility for people who are
5856 already using standard-display-european to continue using unibyte
5857 characters for their work until they want to change.
5858
5859 *** Input methods
5860
5861 An input method is a kind of character conversion which is designed
5862 specifically for interactive input. In Emacs, typically each language
5863 has its own input method (though sometimes several languages which use
5864 the same characters can share one input method). Some languages
5865 support several input methods.
5866
5867 The simplest kind of input method works by mapping ASCII letters into
5868 another alphabet. This is how the Greek and Russian input methods
5869 work.
5870
5871 A more powerful technique is composition: converting sequences of
5872 characters into one letter. Many European input methods use
5873 composition to produce a single non-ASCII letter from a sequence which
5874 consists of a letter followed by diacritics. For example, a' is one
5875 sequence of two characters that might be converted into a single
5876 letter.
5877
5878 The input methods for syllabic scripts typically use mapping followed
5879 by conversion. The input methods for Thai and Korean work this way.
5880 First, letters are mapped into symbols for particular sounds or tone
5881 marks; then, sequences of these which make up a whole syllable are
5882 mapped into one syllable sign--most often a "composite character".
5883
5884 None of these methods works very well for Chinese and Japanese, so
5885 they are handled specially. First you input a whole word using
5886 phonetic spelling; then, after the word is in the buffer, Emacs
5887 converts it into one or more characters using a large dictionary.
5888
5889 Since there is more than one way to represent a phonetically spelled
5890 word using Chinese characters, Emacs can only guess which one to use;
5891 typically these input methods give you a way to say "guess again" if
5892 the first guess is wrong.
5893
5894 *** The command C-x RET m (toggle-enable-multibyte-characters)
5895 turns multibyte character support on or off for the current buffer.
5896
5897 If multibyte character support is turned off in a buffer, then each
5898 byte is a single character, even codes 0200 through 0377--exactly as
5899 they did in Emacs 19.34. This includes the features for support for
5900 the European characters, ISO Latin-1 and ISO Latin-2.
5901
5902 However, there is no need to turn off multibyte character support to
5903 use ISO Latin-1 or ISO Latin-2; the Emacs multibyte character set
5904 includes all the characters in these character sets, and Emacs can
5905 translate automatically to and from either one.
5906
5907 *** Visiting a file in unibyte mode.
5908
5909 Turning off multibyte character support in the buffer after visiting a
5910 file with multibyte code conversion will display the multibyte
5911 sequences already in the buffer, byte by byte. This is probably not
5912 what you want.
5913
5914 If you want to edit a file of unibyte characters (Latin-1, for
5915 example), you can do it by specifying `no-conversion' as the coding
5916 system when reading the file. This coding system also turns off
5917 multibyte characters in that buffer.
5918
5919 If you turn off multibyte character support entirely, this turns off
5920 character conversion as well.
5921
5922 *** Displaying international characters on X Windows.
5923
5924 A font for X typically displays just one alphabet or script.
5925 Therefore, displaying the entire range of characters Emacs supports
5926 requires using many fonts.
5927
5928 Therefore, Emacs now supports "fontsets". Each fontset is a
5929 collection of fonts, each assigned to a range of character codes.
5930
5931 A fontset has a name, like a font. Individual fonts are defined by
5932 the X server; fontsets are defined within Emacs itself. But once you
5933 have defined a fontset, you can use it in a face or a frame just as
5934 you would use a font.
5935
5936 If a fontset specifies no font for a certain character, or if it
5937 specifies a font that does not exist on your system, then it cannot
5938 display that character. It will display an empty box instead.
5939
5940 The fontset height and width are determined by the ASCII characters
5941 (that is, by the font in the fontset which is used for ASCII
5942 characters). If another font in the fontset has a different height,
5943 or the wrong width, then characters assigned to that font are clipped,
5944 and displayed within a box if highlight-wrong-size-font is non-nil.
5945
5946 *** Defining fontsets.
5947
5948 Emacs does not use any fontset by default. Its default font is still
5949 chosen as in previous versions. You can tell Emacs to use a fontset
5950 with the `-fn' option or the `Font' X resource.
5951
5952 Emacs creates a standard fontset automatically according to the value
5953 of standard-fontset-spec. This fontset's short name is
5954 `fontset-standard'. Bold, italic, and bold-italic variants of the
5955 standard fontset are created automatically.
5956
5957 If you specify a default ASCII font with the `Font' resource or `-fn'
5958 argument, a fontset is generated from it. This works by replacing the
5959 FOUNDARY, FAMILY, ADD_STYLE, and AVERAGE_WIDTH fields of the font name
5960 with `*' then using this to specify a fontset. This fontset's short
5961 name is `fontset-startup'.
5962
5963 Emacs checks resources of the form Fontset-N where N is 0, 1, 2...
5964 The resource value should have this form:
5965 FONTSET-NAME, [CHARSET-NAME:FONT-NAME]...
5966 FONTSET-NAME should have the form of a standard X font name, except:
5967 * most fields should be just the wild card "*".
5968 * the CHARSET_REGISTRY field should be "fontset"
5969 * the CHARSET_ENCODING field can be any nickname of the fontset.
5970 The construct CHARSET-NAME:FONT-NAME can be repeated any number
5971 of times; each time specifies the font for one character set.
5972 CHARSET-NAME should be the name name of a character set, and
5973 FONT-NAME should specify an actual font to use for that character set.
5974
5975 Each of these fontsets has an alias which is made from the
5976 last two font name fields, CHARSET_REGISTRY and CHARSET_ENCODING.
5977 You can refer to the fontset by that alias or by its full name.
5978
5979 For any character sets that you don't mention, Emacs tries to choose a
5980 font by substituting into FONTSET-NAME. For instance, with the
5981 following resource,
5982 Emacs*Fontset-0: -*-fixed-medium-r-normal-*-24-*-*-*-*-*-fontset-24
5983 the font for ASCII is generated as below:
5984 -*-fixed-medium-r-normal-*-24-*-ISO8859-1
5985 Here is the substitution rule:
5986 Change CHARSET_REGISTRY and CHARSET_ENCODING to that of the charset
5987 defined in the variable x-charset-registries. For instance, ASCII has
5988 the entry (ascii . "ISO8859-1") in this variable. Then, reduce
5989 sequences of wild cards -*-...-*- with a single wildcard -*-.
5990 (This is to prevent use of auto-scaled fonts.)
5991
5992 The function which processes the fontset resource value to create the
5993 fontset is called create-fontset-from-fontset-spec. You can also call
5994 that function explicitly to create a fontset.
5995
5996 With the X resource Emacs.Font, you can specify a fontset name just
5997 like an actual font name. But be careful not to specify a fontset
5998 name in a wildcard resource like Emacs*Font--that tries to specify the
5999 fontset for other purposes including menus, and they cannot handle
6000 fontsets.
6001
6002 *** The command M-x set-language-environment sets certain global Emacs
6003 defaults for a particular choice of language.
6004
6005 Selecting a language environment typically specifies a default input
6006 method and which coding systems to recognize automatically when
6007 visiting files. However, it does not try to reread files you have
6008 already visited; the text in those buffers is not affected. The
6009 language environment may also specify a default choice of coding
6010 system for new files that you create.
6011
6012 It makes no difference which buffer is current when you use
6013 set-language-environment, because these defaults apply globally to the
6014 whole Emacs session.
6015
6016 For example, M-x set-language-environment RET Latin-1 RET
6017 chooses the Latin-1 character set. In the .emacs file, you can do this
6018 with (set-language-environment "Latin-1").
6019
6020 *** The command C-x RET f (set-buffer-file-coding-system)
6021 specifies the file coding system for the current buffer. This
6022 specifies what sort of character code translation to do when saving
6023 the file. As an argument, you must specify the name of one of the
6024 coding systems that Emacs supports.
6025
6026 *** The command C-x RET c (universal-coding-system-argument)
6027 lets you specify a coding system when you read or write a file.
6028 This command uses the minibuffer to read a coding system name.
6029 After you exit the minibuffer, the specified coding system
6030 is used for *the immediately following command*.
6031
6032 So if the immediately following command is a command to read or
6033 write a file, it uses the specified coding system for that file.
6034
6035 If the immediately following command does not use the coding system,
6036 then C-x RET c ultimately has no effect.
6037
6038 For example, C-x RET c iso-8859-1 RET C-x C-f temp RET
6039 visits the file `temp' treating it as ISO Latin-1.
6040
6041 *** You can specify the coding system for a file using the -*-
6042 construct. Include `coding: CODINGSYSTEM;' inside the -*-...-*-
6043 to specify use of coding system CODINGSYSTEM. You can also
6044 specify the coding system in a local variable list at the end
6045 of the file.
6046
6047 *** The command C-x RET t (set-terminal-coding-system) specifies
6048 the coding system for terminal output. If you specify a character
6049 code for terminal output, all characters output to the terminal are
6050 translated into that character code.
6051
6052 This feature is useful for certain character-only terminals built in
6053 various countries to support the languages of those countries.
6054
6055 By default, output to the terminal is not translated at all.
6056
6057 *** The command C-x RET k (set-keyboard-coding-system) specifies
6058 the coding system for keyboard input.
6059
6060 Character code translation of keyboard input is useful for terminals
6061 with keys that send non-ASCII graphic characters--for example,
6062 some terminals designed for ISO Latin-1 or subsets of it.
6063
6064 By default, keyboard input is not translated at all.
6065
6066 Character code translation of keyboard input is similar to using an
6067 input method, in that both define sequences of keyboard input that
6068 translate into single characters. However, input methods are designed
6069 to be convenient for interactive use, while the code translations are
6070 designed to work with terminals.
6071
6072 *** The command C-x RET p (set-buffer-process-coding-system)
6073 specifies the coding system for input and output to a subprocess.
6074 This command applies to the current buffer; normally, each subprocess
6075 has its own buffer, and thus you can use this command to specify
6076 translation to and from a particular subprocess by giving the command
6077 in the corresponding buffer.
6078
6079 By default, process input and output are not translated at all.
6080
6081 *** The variable file-name-coding-system specifies the coding system
6082 to use for encoding file names before operating on them.
6083 It is also used for decoding file names obtained from the system.
6084
6085 *** The command C-\ (toggle-input-method) activates or deactivates
6086 an input method. If no input method has been selected before, the
6087 command prompts for you to specify the language and input method you
6088 want to use.
6089
6090 C-u C-\ (select-input-method) lets you switch to a different input
6091 method. C-h C-\ (or C-h I) describes the current input method.
6092
6093 *** Some input methods remap the keyboard to emulate various keyboard
6094 layouts commonly used for particular scripts. How to do this
6095 remapping properly depends on your actual keyboard layout. To specify
6096 which layout your keyboard has, use M-x quail-set-keyboard-layout.
6097
6098 *** The command C-h C (describe-coding-system) displays
6099 the coding systems currently selected for various purposes, plus
6100 related information.
6101
6102 *** The command C-h h (view-hello-file) displays a file called
6103 HELLO, which has examples of text in many languages, using various
6104 scripts.
6105
6106 *** The command C-h L (describe-language-support) displays
6107 information about the support for a particular language.
6108 You specify the language as an argument.
6109
6110 *** The mode line now contains a letter or character that identifies
6111 the coding system used in the visited file. It normally follows the
6112 first dash.
6113
6114 A dash indicates the default state of affairs: no code conversion
6115 (except CRLF => newline if appropriate). `=' means no conversion
6116 whatsoever. The ISO 8859 coding systems are represented by digits
6117 1 through 9. Other coding systems are represented by letters:
6118
6119 A alternativnyj (Russian)
6120 B big5 (Chinese)
6121 C cn-gb-2312 (Chinese)
6122 C iso-2022-cn (Chinese)
6123 D in-is13194-devanagari (Indian languages)
6124 E euc-japan (Japanese)
6125 I iso-2022-cjk or iso-2022-ss2 (Chinese, Japanese, Korean)
6126 J junet (iso-2022-7) or old-jis (iso-2022-jp-1978-irv) (Japanese)
6127 K euc-korea (Korean)
6128 R koi8 (Russian)
6129 Q tibetan
6130 S shift_jis (Japanese)
6131 T lao
6132 T tis620 (Thai)
6133 V viscii or vscii (Vietnamese)
6134 i iso-2022-lock (Chinese, Japanese, Korean)
6135 k iso-2022-kr (Korean)
6136 v viqr (Vietnamese)
6137 z hz (Chinese)
6138
6139 When you are using a character-only terminal (not a window system),
6140 two additional characters appear in between the dash and the file
6141 coding system. These two characters describe the coding system for
6142 keyboard input, and the coding system for terminal output.
6143
6144 *** The new variable rmail-file-coding-system specifies the code
6145 conversion to use for RMAIL files. The default value is nil.
6146
6147 When you read mail with Rmail, each message is decoded automatically
6148 into Emacs' internal format. This has nothing to do with
6149 rmail-file-coding-system. That variable controls reading and writing
6150 Rmail files themselves.
6151
6152 *** The new variable sendmail-coding-system specifies the code
6153 conversion for outgoing mail. The default value is nil.
6154
6155 Actually, there are three different ways of specifying the coding system
6156 for sending mail:
6157
6158 - If you use C-x RET f in the mail buffer, that takes priority.
6159 - Otherwise, if you set sendmail-coding-system non-nil, that specifies it.
6160 - Otherwise, the default coding system for new files is used,
6161 if that is non-nil. That comes from your language environment.
6162 - Otherwise, Latin-1 is used.
6163
6164 *** The command C-h t (help-with-tutorial) accepts a prefix argument
6165 to specify the language for the tutorial file. Currently, English,
6166 Japanese, Korean and Thai are supported. We welcome additional
6167 translations.
6168
6169 ** An easy new way to visit a file with no code or format conversion
6170 of any kind: Use M-x find-file-literally. There is also a command
6171 insert-file-literally which inserts a file into the current buffer
6172 without any conversion.
6173
6174 ** C-q's handling of octal character codes is changed.
6175 You can now specify any number of octal digits.
6176 RET terminates the digits and is discarded;
6177 any other non-digit terminates the digits and is then used as input.
6178
6179 ** There are new commands for looking up Info documentation for
6180 functions, variables and file names used in your programs.
6181
6182 Type M-x info-lookup-symbol to look up a symbol in the buffer at point.
6183 Type M-x info-lookup-file to look up a file in the buffer at point.
6184
6185 Precisely which Info files are used to look it up depends on the major
6186 mode. For example, in C mode, the GNU libc manual is used.
6187
6188 ** M-TAB in most programming language modes now runs the command
6189 complete-symbol. This command performs completion on the symbol name
6190 in the buffer before point.
6191
6192 With a numeric argument, it performs completion based on the set of
6193 symbols documented in the Info files for the programming language that
6194 you are using.
6195
6196 With no argument, it does completion based on the current tags tables,
6197 just like the old binding of M-TAB (complete-tag).
6198
6199 ** File locking works with NFS now.
6200
6201 The lock file for FILENAME is now a symbolic link named .#FILENAME,
6202 in the same directory as FILENAME.
6203
6204 This means that collision detection between two different machines now
6205 works reasonably well; it also means that no file server or directory
6206 can become a bottleneck.
6207
6208 The new method does have drawbacks. It means that collision detection
6209 does not operate when you edit a file in a directory where you cannot
6210 create new files. Collision detection also doesn't operate when the
6211 file server does not support symbolic links. But these conditions are
6212 rare, and the ability to have collision detection while using NFS is
6213 so useful that the change is worth while.
6214
6215 When Emacs or a system crashes, this may leave behind lock files which
6216 are stale. So you may occasionally get warnings about spurious
6217 collisions. When you determine that the collision is spurious, just
6218 tell Emacs to go ahead anyway.
6219
6220 ** If you wish to use Show Paren mode to display matching parentheses,
6221 it is no longer sufficient to load paren.el. Instead you must call
6222 show-paren-mode.
6223
6224 ** If you wish to use Delete Selection mode to replace a highlighted
6225 selection when you insert new text, it is no longer sufficient to load
6226 delsel.el. Instead you must call the function delete-selection-mode.
6227
6228 ** If you wish to use Partial Completion mode to complete partial words
6229 within symbols or filenames, it is no longer sufficient to load
6230 complete.el. Instead you must call the function partial-completion-mode.
6231
6232 ** If you wish to use uniquify to rename buffers for you,
6233 it is no longer sufficient to load uniquify.el. You must also
6234 set uniquify-buffer-name-style to one of the non-nil legitimate values.
6235
6236 ** Changes in View mode.
6237
6238 *** Several new commands are available in View mode.
6239 Do H in view mode for a list of commands.
6240
6241 *** There are two new commands for entering View mode:
6242 view-file-other-frame and view-buffer-other-frame.
6243
6244 *** Exiting View mode does a better job of restoring windows to their
6245 previous state.
6246
6247 *** New customization variable view-scroll-auto-exit. If non-nil,
6248 scrolling past end of buffer makes view mode exit.
6249
6250 *** New customization variable view-exits-all-viewing-windows. If
6251 non-nil, view-mode will at exit restore all windows viewing buffer,
6252 not just the selected window.
6253
6254 *** New customization variable view-read-only. If non-nil, visiting a
6255 read-only file automatically enters View mode, and toggle-read-only
6256 turns View mode on or off.
6257
6258 *** New customization variable view-remove-frame-by-deleting controls
6259 how to remove a not needed frame at view mode exit. If non-nil,
6260 delete the frame, if nil make an icon of it.
6261
6262 ** C-x v l, the command to print a file's version control log,
6263 now positions point at the entry for the file's current branch version.
6264
6265 ** C-x v =, the command to compare a file with the last checked-in version,
6266 has a new feature. If the file is currently not locked, so that it is
6267 presumably identical to the last checked-in version, the command now asks
6268 which version to compare with.
6269
6270 ** When using hideshow.el, incremental search can temporarily show hidden
6271 blocks if a match is inside the block.
6272
6273 The block is hidden again if the search is continued and the next match
6274 is outside the block. By customizing the variable
6275 isearch-hide-immediately you can choose to hide all the temporarily
6276 shown blocks only when exiting from incremental search.
6277
6278 By customizing the variable hs-isearch-open you can choose what kind
6279 of blocks to temporarily show during isearch: comment blocks, code
6280 blocks, all of them or none.
6281
6282 ** The new command C-x 4 0 (kill-buffer-and-window) kills the
6283 current buffer and deletes the selected window. It asks for
6284 confirmation first.
6285
6286 ** C-x C-w, which saves the buffer into a specified file name,
6287 now changes the major mode according to that file name.
6288 However, the mode will not be changed if
6289 (1) a local variables list or the `-*-' line specifies a major mode, or
6290 (2) the current major mode is a "special" mode,
6291 not suitable for ordinary files, or
6292 (3) the new file name does not particularly specify any mode.
6293
6294 This applies to M-x set-visited-file-name as well.
6295
6296 However, if you set change-major-mode-with-file-name to nil, then
6297 these commands do not change the major mode.
6298
6299 ** M-x occur changes.
6300
6301 *** If the argument to M-x occur contains upper case letters,
6302 it performs a case-sensitive search.
6303
6304 *** In the *Occur* buffer made by M-x occur,
6305 if you type g or M-x revert-buffer, this repeats the search
6306 using the same regular expression and the same buffer as before.
6307
6308 ** In Transient Mark mode, the region in any one buffer is highlighted
6309 in just one window at a time. At first, it is highlighted in the
6310 window where you set the mark. The buffer's highlighting remains in
6311 that window unless you select to another window which shows the same
6312 buffer--then the highlighting moves to that window.
6313
6314 ** The feature to suggest key bindings when you use M-x now operates
6315 after the command finishes. The message suggesting key bindings
6316 appears temporarily in the echo area. The previous echo area contents
6317 come back after a few seconds, in case they contain useful information.
6318
6319 ** Each frame now independently records the order for recently
6320 selected buffers, so that the default for C-x b is now based on the
6321 buffers recently selected in the selected frame.
6322
6323 ** Outline mode changes.
6324
6325 *** Outline mode now uses overlays (this is the former noutline.el).
6326
6327 *** Incremental searches skip over invisible text in Outline mode.
6328
6329 ** When a minibuffer window is active but not the selected window, if
6330 you try to use the minibuffer, you used to get a nested minibuffer.
6331 Now, this not only gives an error, it also cancels the minibuffer that
6332 was already active.
6333
6334 The motive for this change is so that beginning users do not
6335 unknowingly move away from minibuffers, leaving them active, and then
6336 get confused by it.
6337
6338 If you want to be able to have recursive minibuffers, you must
6339 set enable-recursive-minibuffers to non-nil.
6340
6341 ** Changes in dynamic abbrevs.
6342
6343 *** Expanding dynamic abbrevs with M-/ is now smarter about case
6344 conversion. If the expansion has mixed case not counting the first
6345 character, and the abbreviation matches the beginning of the expansion
6346 including case, then the expansion is copied verbatim.
6347
6348 The expansion is also copied verbatim if the abbreviation itself has
6349 mixed case. And using SPC M-/ to copy an additional word always
6350 copies it verbatim except when the previous copied word is all caps.
6351
6352 *** The values of `dabbrev-case-replace' and `dabbrev-case-fold-search'
6353 are no longer Lisp expressions. They have simply three possible
6354 values.
6355
6356 `dabbrev-case-replace' has these three values: nil (don't preserve
6357 case), t (do), or `case-replace' (do like M-x query-replace).
6358 `dabbrev-case-fold-search' has these three values: nil (don't ignore
6359 case), t (do), or `case-fold-search' (do like search).
6360
6361 ** Minibuffer history lists are truncated automatically now to a
6362 certain length. The variable history-length specifies how long they
6363 can be. The default value is 30.
6364
6365 ** Changes in Mail mode.
6366
6367 *** The key C-x m no longer runs the `mail' command directly.
6368 Instead, it runs the command `compose-mail', which invokes the mail
6369 composition mechanism you have selected with the variable
6370 `mail-user-agent'. The default choice of user agent is
6371 `sendmail-user-agent', which gives behavior compatible with the old
6372 behavior.
6373
6374 C-x 4 m now runs compose-mail-other-window, and C-x 5 m runs
6375 compose-mail-other-frame.
6376
6377 *** While composing a reply to a mail message, from Rmail, you can use
6378 the command C-c C-r to cite just the region from the message you are
6379 replying to. This copies the text which is the selected region in the
6380 buffer that shows the original message.
6381
6382 *** The command C-c C-i inserts a file at the end of the message,
6383 with separator lines around the contents.
6384
6385 *** The command M-x expand-mail-aliases expands all mail aliases
6386 in suitable mail headers. Emacs automatically extracts mail alias
6387 definitions from your mail alias file (e.g., ~/.mailrc). You do not
6388 need to expand mail aliases yourself before sending mail.
6389
6390 *** New features in the mail-complete command.
6391
6392 **** The mail-complete command now inserts the user's full name,
6393 for local users or if that is known. The variable mail-complete-style
6394 controls the style to use, and whether to do this at all.
6395 Its values are like those of mail-from-style.
6396
6397 **** The variable mail-passwd-command lets you specify a shell command
6398 to run to fetch a set of password-entries that add to the ones in
6399 /etc/passwd.
6400
6401 **** The variable mail-passwd-file now specifies a list of files to read
6402 to get the list of user ids. By default, one file is used:
6403 /etc/passwd.
6404
6405 ** You can "quote" a file name to inhibit special significance of
6406 special syntax, by adding `/:' to the beginning. Thus, if you have a
6407 directory named `/foo:', you can prevent it from being treated as a
6408 reference to a remote host named `foo' by writing it as `/:/foo:'.
6409
6410 Emacs uses this new construct automatically when necessary, such as
6411 when you start it with a working directory whose name might otherwise
6412 be taken to be magic.
6413
6414 ** There is a new command M-x grep-find which uses find to select
6415 files to search through, and grep to scan them. The output is
6416 available in a Compile mode buffer, as with M-x grep.
6417
6418 M-x grep now uses the -e option if the grep program supports that.
6419 (-e prevents problems if the search pattern starts with a dash.)
6420
6421 ** In Dired, the & command now flags for deletion the files whose names
6422 suggest they are probably not needed in the long run.
6423
6424 In Dired, * is now a prefix key for mark-related commands.
6425
6426 new key dired.el binding old key
6427 ------- ---------------- -------
6428 * c dired-change-marks c
6429 * m dired-mark m
6430 * * dired-mark-executables * (binding deleted)
6431 * / dired-mark-directories / (binding deleted)
6432 * @ dired-mark-symlinks @ (binding deleted)
6433 * u dired-unmark u
6434 * DEL dired-unmark-backward DEL
6435 * ? dired-unmark-all-files M-C-?
6436 * ! dired-unmark-all-marks
6437 * % dired-mark-files-regexp % m
6438 * C-n dired-next-marked-file M-}
6439 * C-p dired-prev-marked-file M-{
6440
6441 ** Rmail changes.
6442
6443 *** When Rmail cannot convert your incoming mail into Babyl format, it
6444 saves the new mail in the file RMAILOSE.n, where n is an integer
6445 chosen to make a unique name. This way, Rmail will not keep crashing
6446 each time you run it.
6447
6448 *** In Rmail, the variable rmail-summary-line-count-flag now controls
6449 whether to include the line count in the summary. Non-nil means yes.
6450
6451 *** In Rmail summary buffers, d and C-d (the commands to delete
6452 messages) now take repeat counts as arguments. A negative argument
6453 means to move in the opposite direction.
6454
6455 *** In Rmail, the t command now takes an optional argument which lets
6456 you specify whether to show the message headers in full or pruned.
6457
6458 *** In Rmail, the new command w (rmail-output-body-to-file) writes
6459 just the body of the current message into a file, without the headers.
6460 It takes the file name from the message subject, by default, but you
6461 can edit that file name in the minibuffer before it is actually used
6462 for output.
6463
6464 ** Gnus changes.
6465
6466 *** nntp.el has been totally rewritten in an asynchronous fashion.
6467
6468 *** Article prefetching functionality has been moved up into
6469 Gnus.
6470
6471 *** Scoring can now be performed with logical operators like
6472 `and', `or', `not', and parent redirection.
6473
6474 *** Article washing status can be displayed in the
6475 article mode line.
6476
6477 *** gnus.el has been split into many smaller files.
6478
6479 *** Suppression of duplicate articles based on Message-ID.
6480
6481 (setq gnus-suppress-duplicates t)
6482
6483 *** New variables for specifying what score and adapt files
6484 are to be considered home score and adapt files. See
6485 `gnus-home-score-file' and `gnus-home-adapt-files'.
6486
6487 *** Groups can inherit group parameters from parent topics.
6488
6489 *** Article editing has been revamped and is now usable.
6490
6491 *** Signatures can be recognized in more intelligent fashions.
6492 See `gnus-signature-separator' and `gnus-signature-limit'.
6493
6494 *** Summary pick mode has been made to look more nn-like.
6495 Line numbers are displayed and the `.' command can be
6496 used to pick articles.
6497
6498 *** Commands for moving the .newsrc.eld from one server to
6499 another have been added.
6500
6501 `M-x gnus-change-server'
6502
6503 *** A way to specify that "uninteresting" fields be suppressed when
6504 generating lines in buffers.
6505
6506 *** Several commands in the group buffer can be undone with
6507 `M-C-_'.
6508
6509 *** Scoring can be done on words using the new score type `w'.
6510
6511 *** Adaptive scoring can be done on a Subject word-by-word basis:
6512
6513 (setq gnus-use-adaptive-scoring '(word))
6514
6515 *** Scores can be decayed.
6516
6517 (setq gnus-decay-scores t)
6518
6519 *** Scoring can be performed using a regexp on the Date header. The
6520 Date is normalized to compact ISO 8601 format first.
6521
6522 *** A new command has been added to remove all data on articles from
6523 the native server.
6524
6525 `M-x gnus-group-clear-data-on-native-groups'
6526
6527 *** A new command for reading collections of documents
6528 (nndoc with nnvirtual on top) has been added -- `M-C-d'.
6529
6530 *** Process mark sets can be pushed and popped.
6531
6532 *** A new mail-to-news backend makes it possible to post
6533 even when the NNTP server doesn't allow posting.
6534
6535 *** A new backend for reading searches from Web search engines
6536 (DejaNews, Alta Vista, InReference) has been added.
6537
6538 Use the `G w' command in the group buffer to create such
6539 a group.
6540
6541 *** Groups inside topics can now be sorted using the standard
6542 sorting functions, and each topic can be sorted independently.
6543
6544 See the commands under the `T S' submap.
6545
6546 *** Subsets of the groups can be sorted independently.
6547
6548 See the commands under the `G P' submap.
6549
6550 *** Cached articles can be pulled into the groups.
6551
6552 Use the `Y c' command.
6553
6554 *** Score files are now applied in a more reliable order.
6555
6556 *** Reports on where mail messages end up can be generated.
6557
6558 `M-x nnmail-split-history'
6559
6560 *** More hooks and functions have been added to remove junk
6561 from incoming mail before saving the mail.
6562
6563 See `nnmail-prepare-incoming-header-hook'.
6564
6565 *** The nnml mail backend now understands compressed article files.
6566
6567 *** To enable Gnus to read/post multi-lingual articles, you must execute
6568 the following code, for instance, in your .emacs.
6569
6570 (add-hook 'gnus-startup-hook 'gnus-mule-initialize)
6571
6572 Then, when you start Gnus, it will decode non-ASCII text automatically
6573 and show appropriate characters. (Note: if you are using gnus-mime
6574 from the SEMI package, formerly known as TM, you should NOT add this
6575 hook to gnus-startup-hook; gnus-mime has its own method of handling
6576 this issue.)
6577
6578 Since it is impossible to distinguish all coding systems
6579 automatically, you may need to specify a choice of coding system for a
6580 particular news group. This can be done by:
6581
6582 (gnus-mule-add-group NEWSGROUP 'CODING-SYSTEM)
6583
6584 Here NEWSGROUP should be a string which names a newsgroup or a tree
6585 of newsgroups. If NEWSGROUP is "XXX.YYY", all news groups under
6586 "XXX.YYY" (including "XXX.YYY.ZZZ") will use the specified coding
6587 system. CODING-SYSTEM specifies which coding system to use (for both
6588 for reading and posting).
6589
6590 CODING-SYSTEM can also be a cons cell of the form
6591 (READ-CODING-SYSTEM . POST-CODING-SYSTEM)
6592 Then READ-CODING-SYSTEM is used when you read messages from the
6593 newsgroups, while POST-CODING-SYSTEM is used when you post messages
6594 there.
6595
6596 Emacs knows the right coding systems for certain newsgroups by
6597 default. Here are some of these default settings:
6598
6599 (gnus-mule-add-group "fj" 'iso-2022-7)
6600 (gnus-mule-add-group "alt.chinese.text" 'hz-gb-2312)
6601 (gnus-mule-add-group "alt.hk" 'hz-gb-2312)
6602 (gnus-mule-add-group "alt.chinese.text.big5" 'cn-big5)
6603 (gnus-mule-add-group "soc.culture.vietnamese" '(nil . viqr))
6604
6605 When you reply by mail to an article, these settings are ignored;
6606 the mail is encoded according to sendmail-coding-system, as usual.
6607
6608 ** CC mode changes.
6609
6610 *** If you edit primarily one style of C (or C++, Objective-C, Java)
6611 code, you may want to make the CC Mode style variables have global
6612 values so that you can set them directly in your .emacs file. To do
6613 this, set c-style-variables-are-local-p to nil in your .emacs file.
6614 Note that this only takes effect if you do it *before* cc-mode.el is
6615 loaded.
6616
6617 If you typically edit more than one style of C (or C++, Objective-C,
6618 Java) code in a single Emacs session, you may want to make the CC Mode
6619 style variables have buffer local values. By default, all buffers
6620 share the same style variable settings; to make them buffer local, set
6621 c-style-variables-are-local-p to t in your .emacs file. Note that you
6622 must do this *before* CC Mode is loaded.
6623
6624 *** The new variable c-indentation-style holds the C style name
6625 of the current buffer.
6626
6627 *** The variable c-block-comments-indent-p has been deleted, because
6628 it is no longer necessary. C mode now handles all the supported styles
6629 of block comments, with no need to say which one you will use.
6630
6631 *** There is a new indentation style "python", which specifies the C
6632 style that the Python developers like.
6633
6634 *** There is a new c-cleanup-list option: brace-elseif-brace.
6635 This says to put ...} else if (...) {... on one line,
6636 just as brace-else-brace says to put ...} else {... on one line.
6637
6638 ** VC Changes [new]
6639
6640 ** In vc-retrieve-snapshot (C-x v r), if you don't specify a snapshot
6641 name, it retrieves the *latest* versions of all files in the current
6642 directory and its subdirectories (aside from files already locked).
6643
6644 This feature is useful if your RCS directory is a link to a common
6645 master directory, and you want to pick up changes made by other
6646 developers.
6647
6648 You can do the same thing for an individual file by typing C-u C-x C-q
6649 RET in a buffer visiting that file.
6650
6651 *** VC can now handle files under CVS that are being "watched" by
6652 other developers. Such files are made read-only by CVS. To get a
6653 writable copy, type C-x C-q in a buffer visiting such a file. VC then
6654 calls "cvs edit", which notifies the other developers of it.
6655
6656 *** vc-version-diff (C-u C-x v =) now suggests reasonable defaults for
6657 version numbers, based on the current state of the file.
6658
6659 ** Calendar changes.
6660
6661 A new function, list-holidays, allows you list holidays or subclasses
6662 of holidays for ranges of years. Related menu items allow you do this
6663 for the year of the selected date, or the following/previous years.
6664
6665 ** ps-print changes
6666
6667 There are some new user variables for customizing the page layout.
6668
6669 *** Paper size, paper orientation, columns
6670
6671 The variable `ps-paper-type' determines the size of paper ps-print
6672 formats for; it should contain one of the symbols:
6673 `a4' `a3' `letter' `legal' `letter-small' `tabloid'
6674 `ledger' `statement' `executive' `a4small' `b4' `b5'
6675 It defaults to `letter'.
6676 If you need other sizes, see the variable `ps-page-dimensions-database'.
6677
6678 The variable `ps-landscape-mode' determines the orientation
6679 of the printing on the page. nil, the default, means "portrait" mode,
6680 non-nil means "landscape" mode.
6681
6682 The variable `ps-number-of-columns' must be a positive integer.
6683 It determines the number of columns both in landscape and portrait mode.
6684 It defaults to 1.
6685
6686 *** Horizontal layout
6687
6688 The horizontal layout is determined by the variables
6689 `ps-left-margin', `ps-inter-column', and `ps-right-margin'.
6690 All are measured in points.
6691
6692 *** Vertical layout
6693
6694 The vertical layout is determined by the variables
6695 `ps-bottom-margin', `ps-top-margin', and `ps-header-offset'.
6696 All are measured in points.
6697
6698 *** Headers
6699
6700 If the variable `ps-print-header' is nil, no header is printed. Then
6701 `ps-header-offset' is not relevant and `ps-top-margin' represents the
6702 margin above the text.
6703
6704 If the variable `ps-print-header-frame' is non-nil, a gaudy
6705 framing box is printed around the header.
6706
6707 The contents of the header are determined by `ps-header-lines',
6708 `ps-show-n-of-n', `ps-left-header' and `ps-right-header'.
6709
6710 The height of the header is determined by `ps-header-line-pad',
6711 `ps-header-font-family', `ps-header-title-font-size' and
6712 `ps-header-font-size'.
6713
6714 *** Font managing
6715
6716 The variable `ps-font-family' determines which font family is to be
6717 used for ordinary text. Its value must be a key symbol in the alist
6718 `ps-font-info-database'. You can add other font families by adding
6719 elements to this alist.
6720
6721 The variable `ps-font-size' determines the size of the font
6722 for ordinary text. It defaults to 8.5 points.
6723
6724 ** hideshow changes.
6725
6726 *** now supports hiding of blocks of single line comments (like // for
6727 C++, ; for lisp).
6728
6729 *** Support for java-mode added.
6730
6731 *** When doing `hs-hide-all' it is now possible to also hide the comments
6732 in the file if `hs-hide-comments-when-hiding-all' is set.
6733
6734 *** The new function `hs-hide-initial-comment' hides the the comments at
6735 the beginning of the files. Finally those huge RCS logs don't stay in your
6736 way! This is run by default when entering the `hs-minor-mode'.
6737
6738 *** Now uses overlays instead of `selective-display', so is more
6739 robust and a lot faster.
6740
6741 *** A block beginning can span multiple lines.
6742
6743 *** The new variable `hs-show-hidden-short-form' if t, directs hideshow
6744 to show only the beginning of a block when it is hidden. See the
6745 documentation for more details.
6746
6747 ** Changes in Enriched mode.
6748
6749 *** When you visit a file in enriched-mode, Emacs will make sure it is
6750 filled to the current fill-column. This behavior is now independent
6751 of the size of the window. When you save the file, the fill-column in
6752 use is stored as well, so that the whole buffer need not be refilled
6753 the next time unless the fill-column is different.
6754
6755 *** use-hard-newlines is now a minor mode. When it is enabled, Emacs
6756 distinguishes between hard and soft newlines, and treats hard newlines
6757 as paragraph boundaries. Otherwise all newlines inserted are marked
6758 as soft, and paragraph boundaries are determined solely from the text.
6759
6760 ** Font Lock mode
6761
6762 *** Custom support
6763
6764 The variables font-lock-face-attributes, font-lock-display-type and
6765 font-lock-background-mode are now obsolete; the recommended way to specify the
6766 faces to use for Font Lock mode is with M-x customize-group on the new custom
6767 group font-lock-highlighting-faces. If you set font-lock-face-attributes in
6768 your ~/.emacs file, Font Lock mode will respect its value. However, you should
6769 consider converting from setting that variable to using M-x customize.
6770
6771 You can still use X resources to specify Font Lock face appearances.
6772
6773 *** Maximum decoration
6774
6775 Fontification now uses the maximum level of decoration supported by
6776 default. Previously, fontification used a mode-specific default level
6777 of decoration, which is typically the minimum level of decoration
6778 supported. You can set font-lock-maximum-decoration to nil
6779 to get the old behavior.
6780
6781 *** New support
6782
6783 Support is now provided for Java, Objective-C, AWK and SIMULA modes.
6784
6785 Note that Font Lock mode can be turned on without knowing exactly what modes
6786 support Font Lock mode, via the command global-font-lock-mode.
6787
6788 *** Configurable support
6789
6790 Support for C, C++, Objective-C and Java can be more easily configured for
6791 additional types and classes via the new variables c-font-lock-extra-types,
6792 c++-font-lock-extra-types, objc-font-lock-extra-types and, you guessed it,
6793 java-font-lock-extra-types. These value of each of these variables should be a
6794 list of regexps matching the extra type names. For example, the default value
6795 of c-font-lock-extra-types is ("\\sw+_t") which means fontification follows the
6796 convention that C type names end in _t. This results in slower fontification.
6797
6798 Of course, you can change the variables that specify fontification in whatever
6799 way you wish, typically by adding regexps. However, these new variables make
6800 it easier to make specific and common changes for the fontification of types.
6801
6802 *** Adding highlighting patterns to existing support
6803
6804 You can use the new function font-lock-add-keywords to add your own
6805 highlighting patterns, such as for project-local or user-specific constructs,
6806 for any mode.
6807
6808 For example, to highlight `FIXME:' words in C comments, put:
6809
6810 (font-lock-add-keywords 'c-mode '(("\\<FIXME:" 0 font-lock-warning-face t)))
6811
6812 in your ~/.emacs.
6813
6814 *** New faces
6815
6816 Font Lock now defines two new faces, font-lock-builtin-face and
6817 font-lock-warning-face. These are intended to highlight builtin keywords,
6818 distinct from a language's normal keywords, and objects that should be brought
6819 to user attention, respectively. Various modes now use these new faces.
6820
6821 *** Changes to fast-lock support mode
6822
6823 The fast-lock package, one of the two Font Lock support modes, can now process
6824 cache files silently. You can use the new variable fast-lock-verbose, in the
6825 same way as font-lock-verbose, to control this feature.
6826
6827 *** Changes to lazy-lock support mode
6828
6829 The lazy-lock package, one of the two Font Lock support modes, can now fontify
6830 according to the true syntactic context relative to other lines. You can use
6831 the new variable lazy-lock-defer-contextually to control this feature. If
6832 non-nil, changes to the buffer will cause subsequent lines in the buffer to be
6833 refontified after lazy-lock-defer-time seconds of idle time. If nil, then only
6834 the modified lines will be refontified; this is the same as the previous Lazy
6835 Lock mode behaviour and the behaviour of Font Lock mode.
6836
6837 This feature is useful in modes where strings or comments can span lines.
6838 For example, if a string or comment terminating character is deleted, then if
6839 this feature is enabled subsequent lines in the buffer will be correctly
6840 refontified to reflect their new syntactic context. Previously, only the line
6841 containing the deleted character would be refontified and you would have to use
6842 the command M-g M-g (font-lock-fontify-block) to refontify some lines.
6843
6844 As a consequence of this new feature, two other variables have changed:
6845
6846 Variable `lazy-lock-defer-driven' is renamed `lazy-lock-defer-on-scrolling'.
6847 Variable `lazy-lock-defer-time' can now only be a time, i.e., a number.
6848 Buffer modes for which on-the-fly deferral applies can be specified via the
6849 new variable `lazy-lock-defer-on-the-fly'.
6850
6851 If you set these variables in your ~/.emacs, then you may have to change those
6852 settings.
6853
6854 ** Ada mode changes.
6855
6856 *** There is now better support for using find-file.el with Ada mode.
6857 If you switch between spec and body, the cursor stays in the same
6858 procedure (modulo overloading). If a spec has no body file yet, but
6859 you try to switch to its body file, Ada mode now generates procedure
6860 stubs.
6861
6862 *** There are two new commands:
6863 - `ada-make-local' : invokes gnatmake on the current buffer
6864 - `ada-check-syntax' : check syntax of current buffer.
6865
6866 The user options `ada-compiler-make', `ada-make-options',
6867 `ada-language-version', `ada-compiler-syntax-check', and
6868 `ada-compile-options' are used within these commands.
6869
6870 *** Ada mode can now work with Outline minor mode. The outline level
6871 is calculated from the indenting, not from syntactic constructs.
6872 Outlining does not work if your code is not correctly indented.
6873
6874 *** The new function `ada-gnat-style' converts the buffer to the style of
6875 formatting used in GNAT. It places two blanks after a comment start,
6876 places one blank between a word end and an opening '(', and puts one
6877 space between a comma and the beginning of a word.
6878
6879 ** Scheme mode changes.
6880
6881 *** Scheme mode indentation now uses many of the facilities of Lisp
6882 mode; therefore, the variables to customize it are the variables used
6883 for Lisp mode which have names starting with `lisp-'. The variables
6884 with names starting with `scheme-' which used to do this no longer
6885 have any effect.
6886
6887 If you want to use different indentation for Scheme and Lisp, this is
6888 still possible, but now you must do it by adding a hook to
6889 scheme-mode-hook, which could work by setting the `lisp-' indentation
6890 variables as buffer-local variables.
6891
6892 *** DSSSL mode is a variant of Scheme mode, for editing DSSSL scripts.
6893 Use M-x dsssl-mode.
6894
6895 ** Changes to the emacsclient program
6896
6897 *** If a socket can't be found, and environment variables LOGNAME or
6898 USER are set, emacsclient now looks for a socket based on the UID
6899 associated with the name. That is an emacsclient running as root
6900 can connect to an Emacs server started by a non-root user.
6901
6902 *** The emacsclient program now accepts an option --no-wait which tells
6903 it to return immediately without waiting for you to "finish" the
6904 buffer in Emacs.
6905
6906 *** The new option --alternate-editor allows to specify an editor to
6907 use if Emacs is not running. The environment variable
6908 ALTERNATE_EDITOR can be used for the same effect; the command line
6909 option takes precedence.
6910
6911 ** M-x eldoc-mode enables a minor mode in which the echo area
6912 constantly shows the parameter list for function being called at point
6913 (in Emacs Lisp and Lisp Interaction modes only).
6914
6915 ** C-x n d now runs the new command narrow-to-defun,
6916 which narrows the accessible parts of the buffer to just
6917 the current defun.
6918
6919 ** Emacs now handles the `--' argument in the standard way; all
6920 following arguments are treated as ordinary file names.
6921
6922 ** On MSDOS and Windows, the bookmark file is now called _emacs.bmk,
6923 and the saved desktop file is now called _emacs.desktop (truncated if
6924 necessary).
6925
6926 ** When you kill a buffer that visits a file,
6927 if there are any registers that save positions in the file,
6928 these register values no longer become completely useless.
6929 If you try to go to such a register with C-x j, then you are
6930 asked whether to visit the file again. If you say yes,
6931 it visits the file and then goes to the same position.
6932
6933 ** When you visit a file that changes frequently outside Emacs--for
6934 example, a log of output from a process that continues to run--it may
6935 be useful for Emacs to revert the file without querying you whenever
6936 you visit the file afresh with C-x C-f.
6937
6938 You can request this behavior for certain files by setting the
6939 variable revert-without-query to a list of regular expressions. If a
6940 file's name matches any of these regular expressions, find-file and
6941 revert-buffer revert the buffer without asking for permission--but
6942 only if you have not edited the buffer text yourself.
6943
6944 ** set-default-font has been renamed to set-frame-font
6945 since it applies only to the current frame.
6946
6947 ** In TeX mode, you can use the variable tex-main-file to specify the
6948 file for tex-file to run TeX on. (By default, tex-main-file is nil,
6949 and tex-file runs TeX on the current visited file.)
6950
6951 This is useful when you are editing a document that consists of
6952 multiple files. In each of the included files, you can set up a local
6953 variable list which specifies the top-level file of your document for
6954 tex-main-file. Then tex-file will run TeX on the whole document
6955 instead of just the file you are editing.
6956
6957 ** RefTeX mode
6958
6959 RefTeX mode is a new minor mode with special support for \label, \ref
6960 and \cite macros in LaTeX documents. RefTeX distinguishes labels of
6961 different environments (equation, figure, ...) and has full support for
6962 multifile documents. To use it, select a buffer with a LaTeX document and
6963 turn the mode on with M-x reftex-mode. Here are the main user commands:
6964
6965 C-c ( reftex-label
6966 Creates a label semi-automatically. RefTeX is context sensitive and
6967 knows which kind of label is needed.
6968
6969 C-c ) reftex-reference
6970 Offers in a menu all labels in the document, along with context of the
6971 label definition. The selected label is referenced as \ref{LABEL}.
6972
6973 C-c [ reftex-citation
6974 Prompts for a regular expression and displays a list of matching BibTeX
6975 database entries. The selected entry is cited with a \cite{KEY} macro.
6976
6977 C-c & reftex-view-crossref
6978 Views the cross reference of a \ref or \cite command near point.
6979
6980 C-c = reftex-toc
6981 Shows a table of contents of the (multifile) document. From there you
6982 can quickly jump to every section.
6983
6984 Under X, RefTeX installs a "Ref" menu in the menu bar, with additional
6985 commands. Press `?' to get help when a prompt mentions this feature.
6986 Full documentation and customization examples are in the file
6987 reftex.el. You can use the finder to view the file documentation:
6988 C-h p --> tex --> reftex.el
6989
6990 ** Changes in BibTeX mode.
6991
6992 *** Info documentation is now available.
6993
6994 *** Don't allow parentheses in string constants anymore. This confused
6995 both the BibTeX program and Emacs BibTeX mode.
6996
6997 *** Renamed variable bibtex-mode-user-optional-fields to
6998 bibtex-user-optional-fields.
6999
7000 *** Removed variable bibtex-include-OPTannote
7001 (use bibtex-user-optional-fields instead).
7002
7003 *** New interactive functions to copy and kill fields and complete
7004 entries to the BibTeX kill ring, from where they can be yanked back by
7005 appropriate functions.
7006
7007 *** New interactive functions for repositioning and marking of
7008 entries. They are bound by default to M-C-l and M-C-h.
7009
7010 *** New hook bibtex-clean-entry-hook. It is called after entry has
7011 been cleaned.
7012
7013 *** New variable bibtex-field-delimiters, which replaces variables
7014 bibtex-field-{left|right}-delimiter.
7015
7016 *** New variable bibtex-entry-delimiters to determine how entries
7017 shall be delimited.
7018
7019 *** Allow preinitialization of fields. See documentation of
7020 bibtex-user-optional-fields, bibtex-entry-field-alist, and
7021 bibtex-include-OPTkey for details.
7022
7023 *** Book and InBook entries require either an author or an editor
7024 field. This is now supported by bibtex.el. Alternative fields are
7025 prefixed with `ALT'.
7026
7027 *** New variable bibtex-entry-format, which replaces variable
7028 bibtex-clean-entry-zap-empty-opts and allows specification of many
7029 formatting options performed on cleaning an entry (see variable
7030 documentation).
7031
7032 *** Even more control on how automatic keys are generated. See
7033 documentation of bibtex-generate-autokey for details. Transcriptions
7034 for foreign languages other than German are now handled, too.
7035
7036 *** New boolean user option bibtex-comma-after-last-field to decide if
7037 comma should be inserted at end of last field.
7038
7039 *** New boolean user option bibtex-align-at-equal-sign to determine if
7040 alignment should be made at left side of field contents or at equal
7041 signs. New user options to control entry layout (e.g. indentation).
7042
7043 *** New function bibtex-fill-entry to realign entries.
7044
7045 *** New function bibtex-reformat to reformat region or buffer.
7046
7047 *** New function bibtex-convert-alien to convert a BibTeX database
7048 from alien sources.
7049
7050 *** New function bibtex-complete-key (similar to bibtex-complete-string)
7051 to complete prefix to a key defined in buffer. Mainly useful in
7052 crossref entries.
7053
7054 *** New function bibtex-count-entries to count entries in buffer or
7055 region.
7056
7057 *** Added support for imenu.
7058
7059 *** The function `bibtex-validate' now checks current region instead
7060 of buffer if mark is active. Now it shows all errors of buffer in a
7061 `compilation mode' buffer. You can use the normal commands (e.g.
7062 `next-error') for compilation modes to jump to errors.
7063
7064 *** New variable `bibtex-string-file-path' to determine where the files
7065 from `bibtex-string-files' are searched.
7066
7067 ** Iso Accents mode now supports Latin-3 as an alternative.
7068
7069 ** The command next-error now opens blocks hidden by hideshow.
7070
7071 ** The function using-unix-filesystems has been replaced by the
7072 functions add-untranslated-filesystem and remove-untranslated-filesystem.
7073 Each of these functions takes the name of a drive letter or directory
7074 as an argument.
7075
7076 When a filesystem is added as untranslated, all files on it are read
7077 and written in binary mode (no cr/lf translation is performed).
7078
7079 ** browse-url changes
7080
7081 *** New methods for: Grail (browse-url-generic), MMM (browse-url-mmm),
7082 Lynx in a separate xterm (browse-url-lynx-xterm) or in an Emacs window
7083 (browse-url-lynx-emacs), remote W3 (browse-url-w3-gnudoit), generic
7084 non-remote-controlled browsers (browse-url-generic) and associated
7085 customization variables.
7086
7087 *** New commands `browse-url-of-region' and `browse-url'.
7088
7089 *** URLs marked up with <URL:...> (RFC1738) work if broken across
7090 lines. Browsing methods can be associated with URL regexps
7091 (e.g. mailto: URLs) via `browse-url-browser-function'.
7092
7093 ** Changes in Ediff
7094
7095 *** Clicking Mouse-2 on a brief command description in Ediff control panel
7096 pops up the Info file for this command.
7097
7098 *** There is now a variable, ediff-autostore-merges, which controls whether
7099 the result of a merge is saved in a file. By default, this is done only when
7100 merge is done from a session group (eg, when merging files in two different
7101 directories).
7102
7103 *** Since Emacs 19.31 (this hasn't been announced before), Ediff can compare
7104 and merge groups of files residing in different directories, or revisions of
7105 files in the same directory.
7106
7107 *** Since Emacs 19.31, Ediff can apply multi-file patches interactively.
7108 The patches must be in the context format or GNU unified format. (The bug
7109 related to the GNU format has now been fixed.)
7110
7111 ** Changes in Viper
7112
7113 *** The startup file is now .viper instead of .vip
7114 *** All variable/function names have been changed to start with viper-
7115 instead of vip-.
7116 *** C-\ now simulates the meta-key in all Viper states.
7117 *** C-z in Insert state now escapes to Vi for the duration of the next
7118 Viper command. In Vi and Insert states, C-z behaves as before.
7119 *** C-c \ escapes to Vi for one command if Viper is in Insert or Emacs states.
7120 *** _ is no longer the meta-key in Vi state.
7121 *** The variable viper-insert-state-cursor-color can be used to change cursor
7122 color when Viper is in insert state.
7123 *** If search lands the cursor near the top or the bottom of the window,
7124 Viper pulls the window up or down to expose more context. The variable
7125 viper-adjust-window-after-search controls this behavior.
7126
7127 ** Etags changes.
7128
7129 *** In C, C++, Objective C and Java, Etags tags global variables by
7130 default. The resulting tags files are inflated by 30% on average.
7131 Use --no-globals to turn this feature off. Etags can also tag
7132 variables which are members of structure-like constructs, but it does
7133 not by default. Use --members to turn this feature on.
7134
7135 *** C++ member functions are now recognized as tags.
7136
7137 *** Java is tagged like C++. In addition, "extends" and "implements"
7138 constructs are tagged. Files are recognised by the extension .java.
7139
7140 *** Etags can now handle programs written in Postscript. Files are
7141 recognised by the extensions .ps and .pdb (Postscript with C syntax).
7142 In Postscript, tags are lines that start with a slash.
7143
7144 *** Etags now handles Objective C and Objective C++ code. The usual C and
7145 C++ tags are recognized in these languages; in addition, etags
7146 recognizes special Objective C syntax for classes, class categories,
7147 methods and protocols.
7148
7149 *** Etags also handles Cobol. Files are recognised by the extension
7150 .cobol. The tagged lines are those containing a word that begins in
7151 column 8 and ends in a full stop, i.e. anything that could be a
7152 paragraph name.
7153
7154 *** Regexps in Etags now support intervals, as in ed or grep. The syntax of
7155 an interval is \{M,N\}, and it means to match the preceding expression
7156 at least M times and as many as N times.
7157
7158 ** The format for specifying a custom format for time-stamp to insert
7159 in files has changed slightly.
7160
7161 With the new enhancements to the functionality of format-time-string,
7162 time-stamp-format will change to be eventually compatible with it.
7163 This conversion is being done in two steps to maintain compatibility
7164 with old time-stamp-format values.
7165
7166 In the new scheme, alternate case is signified by the number-sign
7167 (`#') modifier, rather than changing the case of the format character.
7168 This feature is as yet incompletely implemented for compatibility
7169 reasons.
7170
7171 In the old time-stamp-format, all numeric fields defaulted to their
7172 natural width. (With format-time-string, each format has a
7173 fixed-width default.) In this version, you can specify the colon
7174 (`:') modifier to a numeric conversion to mean "give me the historical
7175 time-stamp-format width default." Do not use colon if you are
7176 specifying an explicit width, as in "%02d".
7177
7178 Numbers are no longer truncated to the requested width, except in the
7179 case of "%02y", which continues to give a two-digit year. Digit
7180 truncation probably wasn't being used for anything else anyway.
7181
7182 The new formats will work with old versions of Emacs. New formats are
7183 being recommended now to allow time-stamp-format to change in the
7184 future to be compatible with format-time-string. The new forms being
7185 recommended now will continue to work then.
7186
7187 See the documentation string for the variable time-stamp-format for
7188 details.
7189
7190 ** There are some additional major modes:
7191
7192 dcl-mode, for editing VMS DCL files.
7193 m4-mode, for editing files of m4 input.
7194 meta-mode, for editing MetaFont and MetaPost source files.
7195
7196 ** In Shell mode, the command shell-copy-environment-variable lets you
7197 copy the value of a specified environment variable from the subshell
7198 into Emacs.
7199
7200 ** New Lisp packages include:
7201
7202 *** battery.el displays battery status for laptops.
7203
7204 *** M-x bruce (named after Lenny Bruce) is a program that might
7205 be used for adding some indecent words to your email.
7206
7207 *** M-x crisp-mode enables an emulation for the CRiSP editor.
7208
7209 *** M-x dirtrack arranges for better tracking of directory changes
7210 in shell buffers.
7211
7212 *** The new library elint.el provides for linting of Emacs Lisp code.
7213 See the documentation for `elint-initialize', `elint-current-buffer'
7214 and `elint-defun'.
7215
7216 *** M-x expand-add-abbrevs defines a special kind of abbrev which is
7217 meant for programming constructs. These abbrevs expand like ordinary
7218 ones, when you type SPC, but only at the end of a line and not within
7219 strings or comments.
7220
7221 These abbrevs can act as templates: you can define places within an
7222 abbrev for insertion of additional text. Once you expand the abbrev,
7223 you can then use C-x a p and C-x a n to move back and forth to these
7224 insertion points. Thus you can conveniently insert additional text
7225 at these points.
7226
7227 *** filecache.el remembers the location of files so that you
7228 can visit them by short forms of their names.
7229
7230 *** find-func.el lets you find the definition of the user-loaded
7231 Emacs Lisp function at point.
7232
7233 *** M-x handwrite converts text to a "handwritten" picture.
7234
7235 *** M-x iswitchb-buffer is a command for switching to a buffer, much like
7236 switch-buffer, but it reads the argument in a more helpful way.
7237
7238 *** M-x landmark implements a neural network for landmark learning.
7239
7240 *** M-x locate provides a convenient interface to the `locate' program.
7241
7242 *** M4 mode is a new mode for editing files of m4 input.
7243
7244 *** mantemp.el creates C++ manual template instantiations
7245 from the GCC error messages which indicate which instantiations are needed.
7246
7247 *** mouse-copy.el provides a one-click copy and move feature.
7248 You can drag a region with M-mouse-1, and it is automatically
7249 inserted at point. M-Shift-mouse-1 deletes the text from its
7250 original place after inserting the copy.
7251
7252 *** mouse-drag.el lets you do scrolling by dragging Mouse-2
7253 on the buffer.
7254
7255 You click the mouse and move; that distance either translates into the
7256 velocity to scroll (with mouse-drag-throw) or the distance to scroll
7257 (with mouse-drag-drag). Horizontal scrolling is enabled when needed.
7258
7259 Enable mouse-drag with:
7260 (global-set-key [down-mouse-2] 'mouse-drag-throw)
7261 -or-
7262 (global-set-key [down-mouse-2] 'mouse-drag-drag)
7263
7264 *** mspools.el is useful for determining which mail folders have
7265 mail waiting to be read in them. It works with procmail.
7266
7267 *** Octave mode is a major mode for editing files of input for Octave.
7268 It comes with a facility for communicating with an Octave subprocess.
7269
7270 *** ogonek
7271
7272 The ogonek package provides functions for changing the coding of
7273 Polish diacritic characters in buffers. Codings known from various
7274 platforms are supported such as ISO8859-2, Mazovia, IBM Latin2, and
7275 TeX. For example, you can change the coding from Mazovia to
7276 ISO8859-2. Another example is a change of coding from ISO8859-2 to
7277 prefix notation (in which `/a' stands for the aogonek character, for
7278 instance) and vice versa.
7279
7280 To use this package load it using
7281 M-x load-library [enter] ogonek
7282 Then, you may get an explanation by calling one of
7283 M-x ogonek-jak -- in Polish
7284 M-x ogonek-how -- in English
7285 The info specifies the commands and variables provided as well as the
7286 ways of customization in `.emacs'.
7287
7288 *** Interface to ph.
7289
7290 Emacs provides a client interface to CCSO Nameservers (ph/qi)
7291
7292 The CCSO nameserver is used in many universities to provide directory
7293 services about people. ph.el provides a convenient Emacs interface to
7294 these servers.
7295
7296 *** uce.el is useful for replying to unsolicited commercial email.
7297
7298 *** vcursor.el implements a "virtual cursor" feature.
7299 You can move the virtual cursor with special commands
7300 while the real cursor does not move.
7301
7302 *** webjump.el is a "hot list" package which you can set up
7303 for visiting your favorite web sites.
7304
7305 *** M-x winner-mode is a minor mode which saves window configurations,
7306 so you can move back to other configurations that you have recently used.
7307
7308 ** movemail change
7309
7310 Movemail no longer needs to be installed setuid root in order for POP
7311 mail retrieval to function properly. This is because it no longer
7312 supports the RPOP (reserved-port POP) protocol; instead, it uses the
7313 user's POP password to authenticate to the mail server.
7314
7315 This change was made earlier, but not reported in NEWS before.
7316 \f
7317 * Emacs 20.1 changes for MS-DOS and MS-Windows.
7318
7319 ** Changes in handling MS-DOS/MS-Windows text files.
7320
7321 Emacs handles three different conventions for representing
7322 end-of-line: CRLF for MSDOS, LF for Unix and GNU, and CR (used on the
7323 Macintosh). Emacs determines which convention is used in a specific
7324 file based on the contents of that file (except for certain special
7325 file names), and when it saves the file, it uses the same convention.
7326
7327 To save the file and change the end-of-line convention, you can use
7328 C-x RET f (set-buffer-file-coding-system) to specify a different
7329 coding system for the buffer. Then, when you save the file, the newly
7330 specified coding system will take effect. For example, to save with
7331 LF, specify undecided-unix (or some other ...-unix coding system); to
7332 save with CRLF, specify undecided-dos.
7333 \f
7334 * Lisp Changes in Emacs 20.1
7335
7336 ** Byte-compiled files made with Emacs 20 will, in general, work in
7337 Emacs 19 as well, as long as the source code runs in Emacs 19. And
7338 vice versa: byte-compiled files made with Emacs 19 should also run in
7339 Emacs 20, as long as the program itself works in Emacs 20.
7340
7341 ** Windows-specific functions and variables have been renamed
7342 to start with w32- instead of win32-.
7343
7344 In hacker language, calling something a "win" is a form of praise. We
7345 don't want to praise a non-free Microsoft system, so we don't call it
7346 "win".
7347
7348 ** Basic Lisp changes
7349
7350 *** A symbol whose name starts with a colon now automatically
7351 evaluates to itself. Therefore such a symbol can be used as a constant.
7352
7353 *** The defined purpose of `defconst' has been changed. It should now
7354 be used only for values that should not be changed whether by a program
7355 or by the user.
7356
7357 The actual behavior of defconst has not been changed.
7358
7359 *** There are new macros `when' and `unless'
7360
7361 (when CONDITION BODY...) is short for (if CONDITION (progn BODY...))
7362 (unless CONDITION BODY...) is short for (if CONDITION nil BODY...)
7363
7364 *** Emacs now defines functions caar, cadr, cdar and cddr with their
7365 usual Lisp meanings. For example, caar returns the car of the car of
7366 its argument.
7367
7368 *** equal, when comparing strings, now ignores their text properties.
7369
7370 *** The new function `functionp' tests whether an object is a function.
7371
7372 *** arrayp now returns t for char-tables and bool-vectors.
7373
7374 *** Certain primitives which use characters (as integers) now get an
7375 error if the integer is not a valid character code. These primitives
7376 include insert-char, char-to-string, and the %c construct in the
7377 `format' function.
7378
7379 *** The `require' function now insists on adding a suffix, either .el
7380 or .elc, to the file name. Thus, (require 'foo) will not use a file
7381 whose name is just foo. It insists on foo.el or foo.elc.
7382
7383 *** The `autoload' function, when the file name does not contain
7384 either a directory name or the suffix .el or .elc, insists on
7385 adding one of these suffixes.
7386
7387 *** string-to-number now takes an optional second argument BASE
7388 which specifies the base to use when converting an integer.
7389 If BASE is omitted, base 10 is used.
7390
7391 We have not implemented other radices for floating point numbers,
7392 because that would be much more work and does not seem useful.
7393
7394 *** substring now handles vectors as well as strings.
7395
7396 *** The Common Lisp function eql is no longer defined normally.
7397 You must load the `cl' library to define it.
7398
7399 *** The new macro `with-current-buffer' lets you evaluate an expression
7400 conveniently with a different current buffer. It looks like this:
7401
7402 (with-current-buffer BUFFER BODY-FORMS...)
7403
7404 BUFFER is the expression that says which buffer to use.
7405 BODY-FORMS say what to do in that buffer.
7406
7407 *** The new primitive `save-current-buffer' saves and restores the
7408 choice of current buffer, like `save-excursion', but without saving or
7409 restoring the value of point or the mark. `with-current-buffer'
7410 works using `save-current-buffer'.
7411
7412 *** The new macro `with-temp-file' lets you do some work in a new buffer and
7413 write the output to a specified file. Like `progn', it returns the value
7414 of the last form.
7415
7416 *** The new macro `with-temp-buffer' lets you do some work in a new buffer,
7417 which is discarded after use. Like `progn', it returns the value of the
7418 last form. If you wish to return the buffer contents, use (buffer-string)
7419 as the last form.
7420
7421 *** The new function split-string takes a string, splits it at certain
7422 characters, and returns a list of the substrings in between the
7423 matches.
7424
7425 For example, (split-string "foo bar lose" " +") returns ("foo" "bar" "lose").
7426
7427 *** The new macro with-output-to-string executes some Lisp expressions
7428 with standard-output set up so that all output feeds into a string.
7429 Then it returns that string.
7430
7431 For example, if the current buffer name is `foo',
7432
7433 (with-output-to-string
7434 (princ "The buffer is ")
7435 (princ (buffer-name)))
7436
7437 returns "The buffer is foo".
7438
7439 ** Non-ASCII characters are now supported, if enable-multibyte-characters
7440 is non-nil.
7441
7442 These characters have character codes above 256. When inserted in the
7443 buffer or stored in a string, they are represented as multibyte
7444 characters that occupy several buffer positions each.
7445
7446 *** When enable-multibyte-characters is non-nil, a single character in
7447 a buffer or string can be two or more bytes (as many as four).
7448
7449 Buffers and strings are still made up of unibyte elements;
7450 character positions and string indices are always measured in bytes.
7451 Therefore, moving forward one character can increase the buffer
7452 position by 2, 3 or 4. The function forward-char moves by whole
7453 characters, and therefore is no longer equivalent to
7454 (lambda (n) (goto-char (+ (point) n))).
7455
7456 ASCII characters (codes 0 through 127) are still single bytes, always.
7457 Sequences of byte values 128 through 255 are used to represent
7458 non-ASCII characters. These sequences are called "multibyte
7459 characters".
7460
7461 The first byte of a multibyte character is always in the range 128
7462 through 159 (octal 0200 through 0237). These values are called
7463 "leading codes". The second and subsequent bytes are always in the
7464 range 160 through 255 (octal 0240 through 0377). The first byte, the
7465 leading code, determines how many bytes long the sequence is.
7466
7467 *** The function forward-char moves over characters, and therefore
7468 (forward-char 1) may increase point by more than 1 if it moves over a
7469 multibyte character. Likewise, delete-char always deletes a
7470 character, which may be more than one buffer position.
7471
7472 This means that some Lisp programs, which assume that a character is
7473 always one buffer position, need to be changed.
7474
7475 However, all ASCII characters are always one buffer position.
7476
7477 *** The regexp [\200-\377] no longer matches all non-ASCII characters,
7478 because when enable-multibyte-characters is non-nil, these characters
7479 have codes that are not in the range octal 200 to octal 377. However,
7480 the regexp [^\000-\177] does match all non-ASCII characters,
7481 guaranteed.
7482
7483 *** The function char-boundary-p returns non-nil if position POS is
7484 between two characters in the buffer (not in the middle of a
7485 character).
7486
7487 When the value is non-nil, it says what kind of character follows POS:
7488
7489 0 if POS is at an ASCII character or at the end of range,
7490 1 if POS is before a 2-byte length multi-byte form,
7491 2 if POS is at a head of 3-byte length multi-byte form,
7492 3 if POS is at a head of 4-byte length multi-byte form,
7493 4 if POS is at a head of multi-byte form of a composite character.
7494
7495 *** The function char-bytes returns how many bytes the character CHAR uses.
7496
7497 *** Strings can contain multibyte characters. The function
7498 `length' returns the string length counting bytes, which may be
7499 more than the number of characters.
7500
7501 You can include a multibyte character in a string constant by writing
7502 it literally. You can also represent it with a hex escape,
7503 \xNNNNNNN..., using as many digits as necessary. Any character which
7504 is not a valid hex digit terminates this construct. If you want to
7505 follow it with a character that is a hex digit, write backslash and
7506 newline in between; that will terminate the hex escape.
7507
7508 *** The function concat-chars takes arguments which are characters
7509 and returns a string containing those characters.
7510
7511 *** The function sref access a multibyte character in a string.
7512 (sref STRING INDX) returns the character in STRING at INDEX. INDEX
7513 counts from zero. If INDEX is at a position in the middle of a
7514 character, sref signals an error.
7515
7516 *** The function chars-in-string returns the number of characters
7517 in a string. This is less than the length of the string, if the
7518 string contains multibyte characters (the length counts bytes).
7519
7520 *** The function chars-in-region returns the number of characters
7521 in a region from BEG to END. This is less than (- END BEG) if the
7522 region contains multibyte characters (the length counts bytes).
7523
7524 *** The function string-to-list converts a string to a list of
7525 the characters in it. string-to-vector converts a string
7526 to a vector of the characters in it.
7527
7528 *** The function store-substring alters part of the contents
7529 of a string. You call it as follows:
7530
7531 (store-substring STRING IDX OBJ)
7532
7533 This says to alter STRING, by storing OBJ starting at index IDX in
7534 STRING. OBJ may be either a character or a (smaller) string.
7535 This function really does alter the contents of STRING.
7536 Since it is impossible to change the length of an existing string,
7537 it is an error if OBJ doesn't fit within STRING's actual length.
7538
7539 *** char-width returns the width (in columns) of the character CHAR,
7540 if it were displayed in the current buffer and the selected window.
7541
7542 *** string-width returns the width (in columns) of the text in STRING,
7543 if it were displayed in the current buffer and the selected window.
7544
7545 *** truncate-string-to-width shortens a string, if necessary,
7546 to fit within a certain number of columns. (Of course, it does
7547 not alter the string that you give it; it returns a new string
7548 which contains all or just part of the existing string.)
7549
7550 (truncate-string-to-width STR END-COLUMN &optional START-COLUMN PADDING)
7551
7552 This returns the part of STR up to column END-COLUMN.
7553
7554 The optional argument START-COLUMN specifies the starting column.
7555 If this is non-nil, then the first START-COLUMN columns of the string
7556 are not included in the resulting value.
7557
7558 The optional argument PADDING, if non-nil, is a padding character to be added
7559 at the beginning and end the resulting string, to extend it to exactly
7560 WIDTH columns. If PADDING is nil, that means do not pad; then, if STRING
7561 is narrower than WIDTH, the value is equal to STRING.
7562
7563 If PADDING and START-COLUMN are both non-nil, and if there is no clean
7564 place in STRING that corresponds to START-COLUMN (because one
7565 character extends across that column), then the padding character
7566 PADDING is added one or more times at the beginning of the result
7567 string, so that its columns line up as if it really did start at
7568 column START-COLUMN.
7569
7570 *** When the functions in the list after-change-functions are called,
7571 the third argument is the number of bytes in the pre-change text, not
7572 necessarily the number of characters. It is, in effect, the
7573 difference in buffer position between the beginning and the end of the
7574 changed text, before the change.
7575
7576 *** The characters Emacs uses are classified in various character
7577 sets, each of which has a name which is a symbol. In general there is
7578 one character set for each script, not for each language.
7579
7580 **** The function charsetp tests whether an object is a character set name.
7581
7582 **** The variable charset-list holds a list of character set names.
7583
7584 **** char-charset, given a character code, returns the name of the character
7585 set that the character belongs to. (The value is a symbol.)
7586
7587 **** split-char, given a character code, returns a list containing the
7588 name of the character set, followed by one or two byte-values
7589 which identify the character within that character set.
7590
7591 **** make-char, given a character set name and one or two subsequent
7592 byte-values, constructs a character code. This is roughly the
7593 opposite of split-char.
7594
7595 **** find-charset-region returns a list of the character sets
7596 of all the characters between BEG and END.
7597
7598 **** find-charset-string returns a list of the character sets
7599 of all the characters in a string.
7600
7601 *** Here are the Lisp facilities for working with coding systems
7602 and specifying coding systems.
7603
7604 **** The function coding-system-list returns a list of all coding
7605 system names (symbols). With optional argument t, it returns a list
7606 of all distinct base coding systems, not including variants.
7607 (Variant coding systems are those like latin-1-dos, latin-1-unix
7608 and latin-1-mac which specify the end-of-line conversion as well
7609 as what to do about code conversion.)
7610
7611 **** coding-system-p tests a symbol to see if it is a coding system
7612 name. It returns t if so, nil if not.
7613
7614 **** file-coding-system-alist specifies which coding systems to use
7615 for certain file names. It works like network-coding-system-alist,
7616 except that the PATTERN is matched against the file name.
7617
7618 Each element has the format (PATTERN . VAL), where PATTERN determines
7619 which file names the element applies to. PATTERN should be a regexp
7620 to match against a file name.
7621
7622 VAL is a coding system, a cons cell containing two coding systems, or
7623 a function symbol. If VAL is a coding system, it is used for both
7624 decoding what received from the network stream and encoding what sent
7625 to the network stream. If VAL is a cons cell containing two coding
7626 systems, the car specifies the coding system for decoding, and the cdr
7627 specifies the coding system for encoding.
7628
7629 If VAL is a function symbol, the function must return a coding system
7630 or a cons cell containing two coding systems, which is used as above.
7631
7632 **** The variable network-coding-system-alist specifies
7633 the coding system to use for network sockets.
7634
7635 Each element has the format (PATTERN . VAL), where PATTERN determines
7636 which network sockets the element applies to. PATTERN should be
7637 either a port number or a regular expression matching some network
7638 service names.
7639
7640 VAL is a coding system, a cons cell containing two coding systems, or
7641 a function symbol. If VAL is a coding system, it is used for both
7642 decoding what received from the network stream and encoding what sent
7643 to the network stream. If VAL is a cons cell containing two coding
7644 systems, the car specifies the coding system for decoding, and the cdr
7645 specifies the coding system for encoding.
7646
7647 If VAL is a function symbol, the function must return a coding system
7648 or a cons cell containing two coding systems, which is used as above.
7649
7650 **** process-coding-system-alist specifies which coding systems to use
7651 for certain subprocess. It works like network-coding-system-alist,
7652 except that the PATTERN is matched against the program name used to
7653 start the subprocess.
7654
7655 **** The variable default-process-coding-system specifies the coding
7656 systems to use for subprocess (and net connection) input and output,
7657 when nothing else specifies what to do. The value is a cons cell
7658 (OUTPUT-CODING . INPUT-CODING). OUTPUT-CODING applies to output
7659 to the subprocess, and INPUT-CODING applies to input from it.
7660
7661 **** The variable coding-system-for-write, if non-nil, specifies the
7662 coding system to use for writing a file, or for output to a synchronous
7663 subprocess.
7664
7665 It also applies to any asynchronous subprocess or network connection,
7666 but in a different way: the value of coding-system-for-write when you
7667 start the subprocess or connection affects that subprocess or
7668 connection permanently or until overridden.
7669
7670 The variable coding-system-for-write takes precedence over
7671 file-coding-system-alist, process-coding-system-alist and
7672 network-coding-system-alist, and all other methods of specifying a
7673 coding system for output. But most of the time this variable is nil.
7674 It exists so that Lisp programs can bind it to a specific coding
7675 system for one operation at a time.
7676
7677 **** coding-system-for-read applies similarly to input from
7678 files, subprocesses or network connections.
7679
7680 **** The function process-coding-system tells you what
7681 coding systems(s) an existing subprocess is using.
7682 The value is a cons cell,
7683 (DECODING-CODING-SYSTEM . ENCODING-CODING-SYSTEM)
7684 where DECODING-CODING-SYSTEM is used for decoding output from
7685 the subprocess, and ENCODING-CODING-SYSTEM is used for encoding
7686 input to the subprocess.
7687
7688 **** The function set-process-coding-system can be used to
7689 change the coding systems in use for an existing subprocess.
7690
7691 ** Emacs has a new facility to help users manage the many
7692 customization options. To make a Lisp program work with this facility,
7693 you need to use the new macros defgroup and defcustom.
7694
7695 You use defcustom instead of defvar, for defining a user option
7696 variable. The difference is that you specify two additional pieces of
7697 information (usually): the "type" which says what values are
7698 legitimate, and the "group" which specifies the hierarchy for
7699 customization.
7700
7701 Thus, instead of writing
7702
7703 (defvar foo-blurgoze nil
7704 "*Non-nil means that foo will act very blurgozely.")
7705
7706 you would now write this:
7707
7708 (defcustom foo-blurgoze nil
7709 "*Non-nil means that foo will act very blurgozely."
7710 :type 'boolean
7711 :group foo)
7712
7713 The type `boolean' means that this variable has only
7714 two meaningful states: nil and non-nil. Other type values
7715 describe other possibilities; see the manual for Custom
7716 for a description of them.
7717
7718 The "group" argument is used to specify a group which the option
7719 should belong to. You define a new group like this:
7720
7721 (defgroup ispell nil
7722 "Spell checking using Ispell."
7723 :group 'processes)
7724
7725 The "group" argument in defgroup specifies the parent group. The root
7726 group is called `emacs'; it should not contain any variables itself,
7727 but only other groups. The immediate subgroups of `emacs' correspond
7728 to the keywords used by C-h p. Under these subgroups come
7729 second-level subgroups that belong to individual packages.
7730
7731 Each Emacs package should have its own set of groups. A simple
7732 package should have just one group; a more complex package should
7733 have a hierarchy of its own groups. The sole or root group of a
7734 package should be a subgroup of one or more of the "keyword"
7735 first-level subgroups.
7736
7737 ** New `widget' library for inserting UI components in buffers.
7738
7739 This library, used by the new custom library, is documented in a
7740 separate manual that accompanies Emacs.
7741
7742 ** easy-mmode
7743
7744 The easy-mmode package provides macros and functions that make
7745 developing minor modes easier. Roughly, the programmer has to code
7746 only the functionality of the minor mode. All the rest--toggles,
7747 predicate, and documentation--can be done in one call to the macro
7748 `easy-mmode-define-minor-mode' (see the documentation). See also
7749 `easy-mmode-define-keymap'.
7750
7751 ** Text property changes
7752
7753 *** The `intangible' property now works on overlays as well as on a
7754 text property.
7755
7756 *** The new functions next-char-property-change and
7757 previous-char-property-change scan through the buffer looking for a
7758 place where either a text property or an overlay might change. The
7759 functions take two arguments, POSITION and LIMIT. POSITION is the
7760 starting position for the scan. LIMIT says where to stop the scan.
7761
7762 If no property change is found before LIMIT, the value is LIMIT. If
7763 LIMIT is nil, scan goes to the beginning or end of the accessible part
7764 of the buffer. If no property change is found, the value is the
7765 position of the beginning or end of the buffer.
7766
7767 *** In the `local-map' text property or overlay property, the property
7768 value can now be a symbol whose function definition is a keymap. This
7769 is an alternative to using the keymap itself.
7770
7771 ** Changes in invisibility features
7772
7773 *** Isearch can now temporarily show parts of the buffer which are
7774 hidden by an overlay with a invisible property, when the search match
7775 is inside that portion of the buffer. To enable this the overlay
7776 should have a isearch-open-invisible property which is a function that
7777 would be called having the overlay as an argument, the function should
7778 make the overlay visible.
7779
7780 During incremental search the overlays are shown by modifying the
7781 invisible and intangible properties, if beside this more actions are
7782 needed the overlay should have a isearch-open-invisible-temporary
7783 which is a function. The function is called with 2 arguments: one is
7784 the overlay and the second is nil when it should show the overlay and
7785 t when it should hide it.
7786
7787 *** add-to-invisibility-spec, remove-from-invisibility-spec
7788
7789 Modes that use overlays to hide portions of a buffer should set the
7790 invisible property of the overlay to the mode's name (or another symbol)
7791 and modify the `buffer-invisibility-spec' to include that symbol.
7792 Use `add-to-invisibility-spec' and `remove-from-invisibility-spec' to
7793 manipulate the `buffer-invisibility-spec'.
7794 Here is an example of how to do this:
7795
7796 ;; If we want to display an ellipsis:
7797 (add-to-invisibility-spec '(my-symbol . t))
7798 ;; If you don't want ellipsis:
7799 (add-to-invisibility-spec 'my-symbol)
7800
7801 ...
7802 (overlay-put (make-overlay beginning end) 'invisible 'my-symbol)
7803
7804 ...
7805 ;; When done with the overlays:
7806 (remove-from-invisibility-spec '(my-symbol . t))
7807 ;; Or respectively:
7808 (remove-from-invisibility-spec 'my-symbol)
7809
7810 ** Changes in syntax parsing.
7811
7812 *** The syntax-directed buffer-scan functions (such as
7813 `parse-partial-sexp', `forward-word' and similar functions) can now
7814 obey syntax information specified by text properties, if the variable
7815 `parse-sexp-lookup-properties' is non-nil.
7816
7817 If the value of `parse-sexp-lookup-properties' is nil, the behavior
7818 is as before: the syntax-table of the current buffer is always
7819 used to determine the syntax of the character at the position.
7820
7821 When `parse-sexp-lookup-properties' is non-nil, the syntax of a
7822 character in the buffer is calculated thus:
7823
7824 a) if the `syntax-table' text-property of that character
7825 is a cons, this cons becomes the syntax-type;
7826
7827 Valid values of `syntax-table' text-property are: nil, a valid
7828 syntax-table, and a valid syntax-table element, i.e.,
7829 a cons cell of the form (SYNTAX-CODE . MATCHING-CHAR).
7830
7831 b) if the character's `syntax-table' text-property
7832 is a syntax table, this syntax table is used
7833 (instead of the syntax-table of the current buffer) to
7834 determine the syntax type of the character.
7835
7836 c) otherwise the syntax-type is determined by the syntax-table
7837 of the current buffer.
7838
7839 *** The meaning of \s in regular expressions is also affected by the
7840 value of `parse-sexp-lookup-properties'. The details are the same as
7841 for the syntax-directed buffer-scan functions.
7842
7843 *** There are two new syntax-codes, `!' and `|' (numeric values 14
7844 and 15). A character with a code `!' starts a comment which is ended
7845 only by another character with the same code (unless quoted). A
7846 character with a code `|' starts a string which is ended only by
7847 another character with the same code (unless quoted).
7848
7849 These codes are mainly meant for use as values of the `syntax-table'
7850 text property.
7851
7852 *** The function `parse-partial-sexp' has new semantics for the sixth
7853 arg COMMENTSTOP. If it is `syntax-table', parse stops after the start
7854 of a comment or a string, or after end of a comment or a string.
7855
7856 *** The state-list which the return value from `parse-partial-sexp'
7857 (and can also be used as an argument) now has an optional ninth
7858 element: the character address of the start of last comment or string;
7859 nil if none. The fourth and eighth elements have special values if the
7860 string/comment is started by a "!" or "|" syntax-code.
7861
7862 *** Since new features of `parse-partial-sexp' allow a complete
7863 syntactic parsing, `font-lock' no longer supports
7864 `font-lock-comment-start-regexp'.
7865
7866 ** Changes in face features
7867
7868 *** The face functions are now unconditionally defined in Emacs, even
7869 if it does not support displaying on a device that supports faces.
7870
7871 *** The function face-documentation returns the documentation string
7872 of a face (or nil if it doesn't have one).
7873
7874 *** The function face-bold-p returns t if a face should be bold.
7875 set-face-bold-p sets that flag.
7876
7877 *** The function face-italic-p returns t if a face should be italic.
7878 set-face-italic-p sets that flag.
7879
7880 *** You can now specify foreground and background colors for text
7881 by adding elements of the form (foreground-color . COLOR-NAME)
7882 and (background-color . COLOR-NAME) to the list of faces in
7883 the `face' property (either the character's text property or an
7884 overlay property).
7885
7886 This means that you no longer need to create named faces to use
7887 arbitrary colors in a Lisp package.
7888
7889 ** Changes in file-handling functions
7890
7891 *** File-access primitive functions no longer discard an extra redundant
7892 directory name from the beginning of the file name. In other words,
7893 they no longer do anything special with // or /~. That conversion
7894 is now done only in substitute-in-file-name.
7895
7896 This makes it possible for a Lisp program to open a file whose name
7897 begins with ~.
7898
7899 *** If copy-file is unable to set the date of the output file,
7900 it now signals an error with the condition file-date-error.
7901
7902 *** The inode number returned by file-attributes may be an integer (if
7903 the number fits in a Lisp integer) or a list of integers.
7904
7905 *** insert-file-contents can now read from a special file,
7906 as long as the arguments VISIT and REPLACE are nil.
7907
7908 *** The RAWFILE arg to find-file-noselect, if non-nil, now suppresses
7909 character code conversion as well as other things.
7910
7911 Meanwhile, this feature does work with remote file names
7912 (formerly it did not).
7913
7914 *** Lisp packages which create temporary files should use the TMPDIR
7915 environment variable to decide which directory to put them in.
7916
7917 *** interpreter-mode-alist elements now specify regexps
7918 instead of constant strings.
7919
7920 *** expand-file-name no longer treats `//' or `/~' specially. It used
7921 to delete all the text of a file name up through the first slash of
7922 any `//' or `/~' sequence. Now it passes them straight through.
7923
7924 substitute-in-file-name continues to treat those sequences specially,
7925 in the same way as before.
7926
7927 *** The variable `format-alist' is more general now.
7928 The FROM-FN and TO-FN in a format definition can now be strings
7929 which specify shell commands to use as filters to perform conversion.
7930
7931 *** The new function access-file tries to open a file, and signals an
7932 error if that fails. If the open succeeds, access-file does nothing
7933 else, and returns nil.
7934
7935 *** The function insert-directory now signals an error if the specified
7936 directory cannot be listed.
7937
7938 ** Changes in minibuffer input
7939
7940 *** The functions read-buffer, read-variable, read-command, read-string
7941 read-file-name, read-from-minibuffer and completing-read now take an
7942 additional argument which specifies the default value. If this
7943 argument is non-nil, it should be a string; that string is used in two
7944 ways:
7945
7946 It is returned if the user enters empty input.
7947 It is available through the history command M-n.
7948
7949 *** The functions read-string, read-from-minibuffer,
7950 read-no-blanks-input and completing-read now take an additional
7951 argument INHERIT-INPUT-METHOD. If this is non-nil, then the
7952 minibuffer inherits the current input method and the setting of
7953 enable-multibyte-characters from the previously current buffer.
7954
7955 In an interactive spec, you can use M instead of s to read an
7956 argument in this way.
7957
7958 *** All minibuffer input functions discard text properties
7959 from the text you enter in the minibuffer, unless the variable
7960 minibuffer-allow-text-properties is non-nil.
7961
7962 ** Echo area features
7963
7964 *** Clearing the echo area now runs the normal hook
7965 echo-area-clear-hook. Note that the echo area can be used while the
7966 minibuffer is active; in that case, the minibuffer is still active
7967 after the echo area is cleared.
7968
7969 *** The function current-message returns the message currently displayed
7970 in the echo area, or nil if there is none.
7971
7972 ** Keyboard input features
7973
7974 *** tty-erase-char is a new variable that reports which character was
7975 set up as the terminal's erase character when time Emacs was started.
7976
7977 *** num-nonmacro-input-events is the total number of input events
7978 received so far from the terminal. It does not count those generated
7979 by keyboard macros.
7980
7981 ** Frame-related changes
7982
7983 *** make-frame runs the normal hook before-make-frame-hook just before
7984 creating a frame, and just after creating a frame it runs the abnormal
7985 hook after-make-frame-functions with the new frame as arg.
7986
7987 *** The new hook window-configuration-change-hook is now run every time
7988 the window configuration has changed. The frame whose configuration
7989 has changed is the selected frame when the hook is run.
7990
7991 *** Each frame now independently records the order for recently
7992 selected buffers, in its buffer-list frame parameter, so that the
7993 value of other-buffer is now based on the buffers recently displayed
7994 in the selected frame.
7995
7996 *** The value of the frame parameter vertical-scroll-bars
7997 is now `left', `right' or nil. A non-nil value specifies
7998 which side of the window to put the scroll bars on.
7999
8000 ** X Windows features
8001
8002 *** You can examine X resources for other applications by binding
8003 x-resource-class around a call to x-get-resource. The usual value of
8004 x-resource-class is "Emacs", which is the correct value for Emacs.
8005
8006 *** In menus, checkboxes and radio buttons now actually work.
8007 The menu displays the current status of the box or button.
8008
8009 *** The function x-list-fonts now takes an optional fourth argument
8010 MAXIMUM which sets a limit on how many matching fonts to return.
8011 A smaller value of MAXIMUM makes the function faster.
8012
8013 If the only question is whether *any* font matches the pattern,
8014 it is good to supply 1 for this argument.
8015
8016 ** Subprocess features
8017
8018 *** A reminder: it is no longer necessary for subprocess filter
8019 functions and sentinels to do save-match-data, because Emacs does this
8020 automatically.
8021
8022 *** The new function shell-command-to-string executes a shell command
8023 and returns the output from the command as a string.
8024
8025 *** The new function process-contact returns t for a child process,
8026 and (HOSTNAME SERVICE) for a net connection.
8027
8028 ** An error in running pre-command-hook or post-command-hook
8029 does clear the variable to nil. The documentation was wrong before.
8030
8031 ** In define-key-after, if AFTER is t, the new binding now always goes
8032 at the end of the keymap. If the keymap is a menu, this means it
8033 goes after the other menu items.
8034
8035 ** If you have a program that makes several changes in the same area
8036 of the buffer, you can use the macro combine-after-change-calls
8037 around that Lisp code to make it faster when after-change hooks
8038 are in use.
8039
8040 The macro arranges to call the after-change functions just once for a
8041 series of several changes--if that seems safe.
8042
8043 Don't alter the variables after-change-functions and
8044 after-change-function within the body of a combine-after-change-calls
8045 form.
8046
8047 ** If you define an abbrev (with define-abbrev) whose EXPANSION
8048 is not a string, then the abbrev does not expand in the usual sense,
8049 but its hook is still run.
8050
8051 ** Normally, the Lisp debugger is not used (even if you have enabled it)
8052 for errors that are handled by condition-case.
8053
8054 If you set debug-on-signal to a non-nil value, then the debugger is called
8055 regardless of whether there is a handler for the condition. This is
8056 useful for debugging problems that happen inside of a condition-case.
8057
8058 This mode of operation seems to be unreliable in other ways. Errors that
8059 are normal and ought to be handled, perhaps in timers or process
8060 filters, will instead invoke the debugger. So don't say you weren't
8061 warned.
8062
8063 ** The new variable ring-bell-function lets you specify your own
8064 way for Emacs to "ring the bell".
8065
8066 ** If run-at-time's TIME argument is t, the action is repeated at
8067 integral multiples of REPEAT from the epoch; this is useful for
8068 functions like display-time.
8069
8070 ** You can use the function locate-library to find the precise file
8071 name of a Lisp library. This isn't new, but wasn't documented before.
8072
8073 ** Commands for entering view mode have new optional arguments that
8074 can be used from Lisp. Low-level entrance to and exit from view mode
8075 is done by functions view-mode-enter and view-mode-exit.
8076
8077 ** batch-byte-compile-file now makes Emacs return a nonzero status code
8078 if there is an error in compilation.
8079
8080 ** pop-to-buffer, switch-to-buffer-other-window and
8081 switch-to-buffer-other-frame now accept an additional optional
8082 argument NORECORD, much like switch-to-buffer. If it is non-nil,
8083 they don't put the buffer at the front of the buffer list.
8084
8085 ** If your .emacs file leaves the *scratch* buffer non-empty,
8086 Emacs does not display the startup message, so as to avoid changing
8087 the *scratch* buffer.
8088
8089 ** The new function regexp-opt returns an efficient regexp to match a string.
8090 The arguments are STRINGS and (optionally) PAREN. This function can be used
8091 where regexp matching or searching is intensively used and speed is important,
8092 e.g., in Font Lock mode.
8093
8094 ** The variable buffer-display-count is local to each buffer,
8095 and is incremented each time the buffer is displayed in a window.
8096 It starts at 0 when the buffer is created.
8097
8098 ** The new function compose-mail starts composing a mail message
8099 using the user's chosen mail composition agent (specified with the
8100 variable mail-user-agent). It has variants compose-mail-other-window
8101 and compose-mail-other-frame.
8102
8103 ** The `user-full-name' function now takes an optional parameter which
8104 can either be a number (the UID) or a string (the login name). The
8105 full name of the specified user will be returned.
8106
8107 ** Lisp packages that load files of customizations, or any other sort
8108 of user profile, should obey the variable init-file-user in deciding
8109 where to find it. They should load the profile of the user name found
8110 in that variable. If init-file-user is nil, meaning that the -q
8111 option was used, then Lisp packages should not load the customization
8112 files at all.
8113
8114 ** format-time-string now allows you to specify the field width
8115 and type of padding. This works as in printf: you write the field
8116 width as digits in the middle of a %-construct. If you start
8117 the field width with 0, it means to pad with zeros.
8118
8119 For example, %S normally specifies the number of seconds since the
8120 minute; %03S means to pad this with zeros to 3 positions, %_3S to pad
8121 with spaces to 3 positions. Plain %3S pads with zeros, because that
8122 is how %S normally pads to two positions.
8123
8124 ** thing-at-point now supports a new kind of "thing": url.
8125
8126 ** imenu.el changes.
8127
8128 You can now specify a function to be run when selecting an
8129 item from menu created by imenu.
8130
8131 An example of using this feature: if we define imenu items for the
8132 #include directives in a C file, we can open the included file when we
8133 select one of those items.
8134 \f
8135 * Emacs 19.34 is a bug-fix release with no user-visible changes.
8136 \f
8137 * Changes in Emacs 19.33.
8138
8139 ** Bibtex mode no longer turns on Auto Fill automatically. (No major
8140 mode should do that--it is the user's choice.)
8141
8142 ** The variable normal-auto-fill-function specifies the function to
8143 use for auto-fill-function, if and when Auto Fill is turned on.
8144 Major modes can set this locally to alter how Auto Fill works.
8145 \f
8146 * Editing Changes in Emacs 19.32
8147
8148 ** C-x f with no argument now signals an error.
8149 To set the fill column at the current column, use C-u C-x f.
8150
8151 ** Expanding dynamic abbrevs with M-/ is now smarter about case
8152 conversion. If you type the abbreviation with mixed case, and it
8153 matches the beginning of the expansion including case, then the
8154 expansion is copied verbatim. Using SPC M-/ to copy an additional
8155 word always copies it verbatim except when the previous copied word is
8156 all caps.
8157
8158 ** On a non-windowing terminal, which can display only one Emacs frame
8159 at a time, creating a new frame with C-x 5 2 also selects that frame.
8160
8161 When using a display that can show multiple frames at once, C-x 5 2
8162 does make the frame visible, but does not select it. This is the same
8163 as in previous Emacs versions.
8164
8165 ** You can use C-x 5 2 to create multiple frames on MSDOS, just as on a
8166 non-X terminal on Unix. Of course, only one frame is visible at any
8167 time, since your terminal doesn't have the ability to display multiple
8168 frames.
8169
8170 ** On Windows, set win32-pass-alt-to-system to a non-nil value
8171 if you would like tapping the Alt key to invoke the Windows menu.
8172 This feature is not enabled by default; since the Alt key is also the
8173 Meta key, it is too easy and painful to activate this feature by
8174 accident.
8175
8176 ** The command apply-macro-to-region-lines repeats the last defined
8177 keyboard macro once for each complete line within the current region.
8178 It does this line by line, by moving point to the beginning of that
8179 line and then executing the macro.
8180
8181 This command is not new, but was never documented before.
8182
8183 ** You can now use Mouse-1 to place the region around a string constant
8184 (something surrounded by doublequote characters or other delimiter
8185 characters of like syntax) by double-clicking on one of the delimiting
8186 characters.
8187
8188 ** Font Lock mode
8189
8190 *** Font Lock support modes
8191
8192 Font Lock can be configured to use Fast Lock mode and Lazy Lock mode (see
8193 below) in a flexible way. Rather than adding the appropriate function to the
8194 hook font-lock-mode-hook, you can use the new variable font-lock-support-mode
8195 to control which modes have Fast Lock mode or Lazy Lock mode turned on when
8196 Font Lock mode is enabled.
8197
8198 For example, to use Fast Lock mode when Font Lock mode is turned on, put:
8199
8200 (setq font-lock-support-mode 'fast-lock-mode)
8201
8202 in your ~/.emacs.
8203
8204 *** lazy-lock
8205
8206 The lazy-lock package speeds up Font Lock mode by making fontification occur
8207 only when necessary, such as when a previously unfontified part of the buffer
8208 becomes visible in a window. When you create a buffer with Font Lock mode and
8209 Lazy Lock mode turned on, the buffer is not fontified. When certain events
8210 occur (such as scrolling), Lazy Lock makes sure that the visible parts of the
8211 buffer are fontified. Lazy Lock also defers on-the-fly fontification until
8212 Emacs has been idle for a given amount of time.
8213
8214 To use this package, put in your ~/.emacs:
8215
8216 (setq font-lock-support-mode 'lazy-lock-mode)
8217
8218 To control the package behaviour, see the documentation for `lazy-lock-mode'.
8219
8220 ** Changes in BibTeX mode.
8221
8222 *** For all entries allow spaces and tabs between opening brace or
8223 paren and key.
8224
8225 *** Non-escaped double-quoted characters (as in `Sch"of') are now
8226 supported.
8227
8228 ** Gnus changes.
8229
8230 Gnus, the Emacs news reader, has undergone further rewriting. Many new
8231 commands and variables have been added. There should be no
8232 significant incompatibilities between this Gnus version and the
8233 previously released version, except in the message composition area.
8234
8235 Below is a list of the more user-visible changes. Coding changes
8236 between Gnus 5.1 and 5.2 are more extensive.
8237
8238 *** A new message composition mode is used. All old customization
8239 variables for mail-mode, rnews-reply-mode and gnus-msg are now
8240 obsolete.
8241
8242 *** Gnus is now able to generate "sparse" threads -- threads where
8243 missing articles are represented by empty nodes.
8244
8245 (setq gnus-build-sparse-threads 'some)
8246
8247 *** Outgoing articles are stored on a special archive server.
8248
8249 To disable this: (setq gnus-message-archive-group nil)
8250
8251 *** Partial thread regeneration now happens when articles are
8252 referred.
8253
8254 *** Gnus can make use of GroupLens predictions:
8255
8256 (setq gnus-use-grouplens t)
8257
8258 *** A trn-line tree buffer can be displayed.
8259
8260 (setq gnus-use-trees t)
8261
8262 *** An nn-like pick-and-read minor mode is available for the summary
8263 buffers.
8264
8265 (add-hook 'gnus-summary-mode-hook 'gnus-pick-mode)
8266
8267 *** In binary groups you can use a special binary minor mode:
8268
8269 `M-x gnus-binary-mode'
8270
8271 *** Groups can be grouped in a folding topic hierarchy.
8272
8273 (add-hook 'gnus-group-mode-hook 'gnus-topic-mode)
8274
8275 *** Gnus can re-send and bounce mail.
8276
8277 Use the `S D r' and `S D b'.
8278
8279 *** Groups can now have a score, and bubbling based on entry frequency
8280 is possible.
8281
8282 (add-hook 'gnus-summary-exit-hook 'gnus-summary-bubble-group)
8283
8284 *** Groups can be process-marked, and commands can be performed on
8285 groups of groups.
8286
8287 *** Caching is possible in virtual groups.
8288
8289 *** nndoc now understands all kinds of digests, mail boxes, rnews news
8290 batches, ClariNet briefs collections, and just about everything else.
8291
8292 *** Gnus has a new backend (nnsoup) to create/read SOUP packets.
8293
8294 *** The Gnus cache is much faster.
8295
8296 *** Groups can be sorted according to many criteria.
8297
8298 For instance: (setq gnus-group-sort-function 'gnus-group-sort-by-rank)
8299
8300 *** New group parameters have been introduced to set list-address and
8301 expiration times.
8302
8303 *** All formatting specs allow specifying faces to be used.
8304
8305 *** There are several more commands for setting/removing/acting on
8306 process marked articles on the `M P' submap.
8307
8308 *** The summary buffer can be limited to show parts of the available
8309 articles based on a wide range of criteria. These commands have been
8310 bound to keys on the `/' submap.
8311
8312 *** Articles can be made persistent -- as an alternative to saving
8313 articles with the `*' command.
8314
8315 *** All functions for hiding article elements are now toggles.
8316
8317 *** Article headers can be buttonized.
8318
8319 (add-hook 'gnus-article-display-hook 'gnus-article-add-buttons-to-head)
8320
8321 *** All mail backends support fetching articles by Message-ID.
8322
8323 *** Duplicate mail can now be treated properly. See the
8324 `nnmail-treat-duplicates' variable.
8325
8326 *** All summary mode commands are available directly from the article
8327 buffer.
8328
8329 *** Frames can be part of `gnus-buffer-configuration'.
8330
8331 *** Mail can be re-scanned by a daemonic process.
8332
8333 *** Gnus can make use of NoCeM files to filter spam.
8334
8335 (setq gnus-use-nocem t)
8336
8337 *** Groups can be made permanently visible.
8338
8339 (setq gnus-permanently-visible-groups "^nnml:")
8340
8341 *** Many new hooks have been introduced to make customizing easier.
8342
8343 *** Gnus respects the Mail-Copies-To header.
8344
8345 *** Threads can be gathered by looking at the References header.
8346
8347 (setq gnus-summary-thread-gathering-function
8348 'gnus-gather-threads-by-references)
8349
8350 *** Read articles can be stored in a special backlog buffer to avoid
8351 refetching.
8352
8353 (setq gnus-keep-backlog 50)
8354
8355 *** A clean copy of the current article is always stored in a separate
8356 buffer to allow easier treatment.
8357
8358 *** Gnus can suggest where to save articles. See `gnus-split-methods'.
8359
8360 *** Gnus doesn't have to do as much prompting when saving.
8361
8362 (setq gnus-prompt-before-saving t)
8363
8364 *** gnus-uu can view decoded files asynchronously while fetching
8365 articles.
8366
8367 (setq gnus-uu-grabbed-file-functions 'gnus-uu-grab-view)
8368
8369 *** Filling in the article buffer now works properly on cited text.
8370
8371 *** Hiding cited text adds buttons to toggle hiding, and how much
8372 cited text to hide is now customizable.
8373
8374 (setq gnus-cited-lines-visible 2)
8375
8376 *** Boring headers can be hidden.
8377
8378 (add-hook 'gnus-article-display-hook 'gnus-article-hide-boring-headers)
8379
8380 *** Default scoring values can now be set from the menu bar.
8381
8382 *** Further syntax checking of outgoing articles have been added.
8383
8384 The Gnus manual has been expanded. It explains all these new features
8385 in greater detail.
8386 \f
8387 * Lisp Changes in Emacs 19.32
8388
8389 ** The function set-visited-file-name now accepts an optional
8390 second argument NO-QUERY. If it is non-nil, then the user is not
8391 asked for confirmation in the case where the specified file already
8392 exists.
8393
8394 ** The variable print-length applies to printing vectors and bitvectors,
8395 as well as lists.
8396
8397 ** The new function keymap-parent returns the parent keymap
8398 of a given keymap.
8399
8400 ** The new function set-keymap-parent specifies a new parent for a
8401 given keymap. The arguments are KEYMAP and PARENT. PARENT must be a
8402 keymap or nil.
8403
8404 ** Sometimes menu keymaps use a command name, a symbol, which is really
8405 an automatically generated alias for some other command, the "real"
8406 name. In such a case, you should give that alias symbol a non-nil
8407 menu-alias property. That property tells the menu system to look for
8408 equivalent keys for the real name instead of equivalent keys for the
8409 alias.
8410 \f
8411 * Editing Changes in Emacs 19.31
8412
8413 ** Freedom of the press restricted in the United States.
8414
8415 Emacs has been censored in accord with the Communications Decency Act.
8416 This includes removing some features of the doctor program. That law
8417 was described by its supporters as a ban on pornography, but it bans
8418 far more than that. The Emacs distribution has never contained any
8419 pornography, but parts of it were nonetheless prohibited.
8420
8421 For information on US government censorship of the Internet, and what
8422 you can do to bring back freedom of the press, see the web site
8423 `http://www.vtw.org/'.
8424
8425 ** A note about C mode indentation customization.
8426
8427 The old (Emacs 19.29) ways of specifying a C indentation style
8428 do not normally work in the new implementation of C mode.
8429 It has its own methods of customizing indentation, which are
8430 much more powerful than the old C mode. See the Editing Programs
8431 chapter of the manual for details.
8432
8433 However, you can load the library cc-compat to make the old
8434 customization variables take effect.
8435
8436 ** Marking with the mouse.
8437
8438 When you mark a region with the mouse, the region now remains
8439 highlighted until the next input event, regardless of whether you are
8440 using M-x transient-mark-mode.
8441
8442 ** Improved Windows NT/95 support.
8443
8444 *** Emacs now supports scroll bars on Windows NT and Windows 95.
8445
8446 *** Emacs now supports subprocesses on Windows 95. (Subprocesses used
8447 to work on NT only and not on 95.)
8448
8449 *** There are difficulties with subprocesses, though, due to problems
8450 in Windows, beyond the control of Emacs. They work fine as long as
8451 you run Windows applications. The problems arise when you run a DOS
8452 application in a subprocesses. Since current shells run as DOS
8453 applications, these problems are significant.
8454
8455 If you run a DOS application in a subprocess, then the application is
8456 likely to busy-wait, which means that your machine will be 100% busy.
8457 However, if you don't mind the temporary heavy load, the subprocess
8458 will work OK as long as you tell it to terminate before you start any
8459 other DOS application as a subprocess.
8460
8461 Emacs is unable to terminate or interrupt a DOS subprocess.
8462 You have to do this by providing input directly to the subprocess.
8463
8464 If you run two DOS applications at the same time in two separate
8465 subprocesses, even if one of them is asynchronous, you will probably
8466 have to reboot your machine--until then, it will remain 100% busy.
8467 Windows simply does not cope when one Windows process tries to run two
8468 separate DOS subprocesses. Typing CTL-ALT-DEL and then choosing
8469 Shutdown seems to work although it may take a few minutes.
8470
8471 ** M-x resize-minibuffer-mode.
8472
8473 This command, not previously mentioned in NEWS, toggles a mode in
8474 which the minibuffer window expands to show as many lines as the
8475 minibuffer contains.
8476
8477 ** `title' frame parameter and resource.
8478
8479 The `title' X resource now specifies just the frame title, nothing else.
8480 It does not affect the name used for looking up other X resources.
8481 It works by setting the new `title' frame parameter, which likewise
8482 affects just the displayed title of the frame.
8483
8484 The `name' parameter continues to do what it used to do:
8485 it specifies the frame name for looking up X resources,
8486 and also serves as the default for the displayed title
8487 when the `title' parameter is unspecified or nil.
8488
8489 ** Emacs now uses the X toolkit by default, if you have a new
8490 enough version of X installed (X11R5 or newer).
8491
8492 ** When you compile Emacs with the Motif widget set, Motif handles the
8493 F10 key by activating the menu bar. To avoid confusion, the usual
8494 Emacs binding of F10 is replaced with a no-op when using Motif.
8495
8496 If you want to be able to use F10 in Emacs, you can rebind the Motif
8497 menubar to some other key which you don't use. To do so, add
8498 something like this to your X resources file. This example rebinds
8499 the Motif menu bar activation key to S-F12:
8500
8501 Emacs*defaultVirtualBindings: osfMenuBar : Shift<Key>F12
8502
8503 ** In overwrite mode, DEL now inserts spaces in most cases
8504 to replace the characters it "deletes".
8505
8506 ** The Rmail summary now shows the number of lines in each message.
8507
8508 ** Rmail has a new command M-x unforward-rmail-message, which extracts
8509 a forwarded message from the message that forwarded it. To use it,
8510 select a message which contains a forwarded message and then type the command.
8511 It inserts the forwarded message as a separate Rmail message
8512 immediately after the selected one.
8513
8514 This command also undoes the textual modifications that are standardly
8515 made, as part of forwarding, by Rmail and other mail reader programs.
8516
8517 ** Turning off saving of .saves-... files in your home directory.
8518
8519 Each Emacs session writes a file named .saves-... in your home
8520 directory to record which files M-x recover-session should recover.
8521 If you exit Emacs normally with C-x C-c, it deletes that file. If
8522 Emacs or the operating system crashes, the file remains for M-x
8523 recover-session.
8524
8525 You can turn off the writing of these files by setting
8526 auto-save-list-file-name to nil. If you do this, M-x recover-session
8527 will not work.
8528
8529 Some previous Emacs versions failed to delete these files even on
8530 normal exit. This is fixed now. If you are thinking of turning off
8531 this feature because of past experiences with versions that had this
8532 bug, it would make sense to check whether you still want to do so
8533 now that the bug is fixed.
8534
8535 ** Changes to Version Control (VC)
8536
8537 There is a new variable, vc-follow-symlinks. It indicates what to do
8538 when you visit a link to a file that is under version control.
8539 Editing the file through the link bypasses the version control system,
8540 which is dangerous and probably not what you want.
8541
8542 If this variable is t, VC follows the link and visits the real file,
8543 telling you about it in the echo area. If it is `ask' (the default),
8544 VC asks for confirmation whether it should follow the link. If nil,
8545 the link is visited and a warning displayed.
8546
8547 ** iso-acc.el now lets you specify a choice of language.
8548 Languages include "latin-1" (the default) and "latin-2" (which
8549 is designed for entering ISO Latin-2 characters).
8550
8551 There are also choices for specific human languages such as French and
8552 Portuguese. These are subsets of Latin-1, which differ in that they
8553 enable only the accent characters needed for particular language.
8554 The other accent characters, not needed for the chosen language,
8555 remain normal.
8556
8557 ** Posting articles and sending mail now has M-TAB completion on various
8558 header fields (Newsgroups, To, CC, ...).
8559
8560 Completion in the Newsgroups header depends on the list of groups
8561 known to your news reader. Completion in the Followup-To header
8562 offers those groups which are in the Newsgroups header, since
8563 Followup-To usually just holds one of those.
8564
8565 Completion in fields that hold mail addresses works based on the list
8566 of local users plus your aliases. Additionally, if your site provides
8567 a mail directory or a specific host to use for any unrecognized user
8568 name, you can arrange to query that host for completion also. (See the
8569 documentation of variables `mail-directory-process' and
8570 `mail-directory-stream'.)
8571
8572 ** A greatly extended sgml-mode offers new features such as (to be configured)
8573 skeletons with completing read for tags and attributes, typing named
8574 characters including optionally all 8bit characters, making tags invisible
8575 with optional alternate display text, skipping and deleting tag(pair)s.
8576
8577 Note: since Emacs' syntax feature cannot limit the special meaning of ', " and
8578 - to inside <>, for some texts the result, especially of font locking, may be
8579 wrong (see `sgml-specials' if you get wrong results).
8580
8581 The derived html-mode configures this with tags and attributes more or
8582 less HTML3ish. It also offers optional quick keys like C-c 1 for
8583 headline or C-c u for unordered list (see `html-quick-keys'). Edit /
8584 Text Properties / Face or M-g combinations create tags as applicable.
8585 Outline minor mode is supported and level 1 font-locking tries to
8586 fontify tag contents (which only works when they fit on one line, due
8587 to a limitation in font-lock).
8588
8589 External viewing via browse-url can occur automatically upon saving.
8590
8591 ** M-x imenu-add-to-menubar now adds to the menu bar for the current
8592 buffer only. If you want to put an Imenu item in the menu bar for all
8593 buffers that use a particular major mode, use the mode hook, as in
8594 this example:
8595
8596 (add-hook 'emacs-lisp-mode-hook
8597 '(lambda () (imenu-add-to-menubar "Index")))
8598
8599 ** Changes in BibTeX mode.
8600
8601 *** Field names may now contain digits, hyphens, and underscores.
8602
8603 *** Font Lock mode is now supported.
8604
8605 *** bibtex-make-optional-field is no longer interactive.
8606
8607 *** If bibtex-maintain-sorted-entries is non-nil, inserting new
8608 entries is now done with a faster algorithm. However, inserting
8609 will fail in this case if the buffer contains invalid entries or
8610 isn't in sorted order, so you should finish each entry with C-c C-c
8611 (bibtex-close-entry) after you have inserted or modified it.
8612 The default value of bibtex-maintain-sorted-entries is nil.
8613
8614 *** Function `show-all' is no longer bound to a key, since C-u C-c C-q
8615 does the same job.
8616
8617 *** Entries with quotes inside quote-delimited fields (as `author =
8618 "Stefan Sch{\"o}f"') are now supported.
8619
8620 *** Case in field names doesn't matter anymore when searching for help
8621 text.
8622
8623 ** Font Lock mode
8624
8625 *** Global Font Lock mode
8626
8627 Font Lock mode can be turned on globally, in buffers that support it, by the
8628 new command global-font-lock-mode. You can use the new variable
8629 font-lock-global-modes to control which modes have Font Lock mode automagically
8630 turned on. By default, this variable is set so that Font Lock mode is turned
8631 on globally where the buffer mode supports it.
8632
8633 For example, to automagically turn on Font Lock mode where supported, put:
8634
8635 (global-font-lock-mode t)
8636
8637 in your ~/.emacs.
8638
8639 *** Local Refontification
8640
8641 In Font Lock mode, editing a line automatically refontifies that line only.
8642 However, if your change alters the syntactic context for following lines,
8643 those lines remain incorrectly fontified. To refontify them, use the new
8644 command M-g M-g (font-lock-fontify-block).
8645
8646 In certain major modes, M-g M-g refontifies the entire current function.
8647 (The variable font-lock-mark-block-function controls how to find the
8648 current function.) In other major modes, M-g M-g refontifies 16 lines
8649 above and below point.
8650
8651 With a prefix argument N, M-g M-g refontifies N lines above and below point.
8652
8653 ** Follow mode
8654
8655 Follow mode is a new minor mode combining windows showing the same
8656 buffer into one tall "virtual window". The windows are typically two
8657 side-by-side windows. Follow mode makes them scroll together as if
8658 they were a unit. To use it, go to a frame with just one window,
8659 split it into two side-by-side windows using C-x 3, and then type M-x
8660 follow-mode.
8661
8662 M-x follow-mode turns off Follow mode if it is already enabled.
8663
8664 To display two side-by-side windows and activate Follow mode, use the
8665 command M-x follow-delete-other-windows-and-split.
8666
8667 ** hide-show changes.
8668
8669 The hooks hs-hide-hooks and hs-show-hooks have been renamed
8670 to hs-hide-hook and hs-show-hook, to follow the convention for
8671 normal hooks.
8672
8673 ** Simula mode now has a menu containing the most important commands.
8674 The new command simula-indent-exp is bound to C-M-q.
8675
8676 ** etags can now handle programs written in Erlang. Files are
8677 recognised by the extensions .erl and .hrl. The tagged lines are
8678 those that begin a function, record, or macro.
8679
8680 ** MSDOS Changes
8681
8682 *** It is now possible to compile Emacs with the version 2 of DJGPP.
8683 Compilation with DJGPP version 1 also still works.
8684
8685 *** The documentation of DOS-specific aspects of Emacs was rewritten
8686 and expanded; see the ``MS-DOS'' node in the on-line docs.
8687
8688 *** Emacs now uses ~ for backup file names, not .bak.
8689
8690 *** You can simulate mouse-3 on two-button mice by simultaneously
8691 pressing both mouse buttons.
8692
8693 *** A number of packages and commands which previously failed or had
8694 restricted functionality on MS-DOS, now work. The most important ones
8695 are:
8696
8697 **** Printing (both with `M-x lpr-buffer' and with `ps-print' package)
8698 now works.
8699
8700 **** `Ediff' works (in a single-frame mode).
8701
8702 **** `M-x display-time' can be used on MS-DOS (due to the new
8703 implementation of Emacs timers, see below).
8704
8705 **** `Dired' supports Unix-style shell wildcards.
8706
8707 **** The `c-macro-expand' command now works as on other platforms.
8708
8709 **** `M-x recover-session' works.
8710
8711 **** `M-x list-colors-display' displays all the available colors.
8712
8713 **** The `TPU-EDT' package works.
8714 \f
8715 * Lisp changes in Emacs 19.31.
8716
8717 ** The function using-unix-filesystems on Windows NT and Windows 95
8718 tells Emacs to read and write files assuming that they reside on a
8719 remote Unix filesystem. No CR/LF translation is done on any files in
8720 this case. Invoking using-unix-filesystems with t activates this
8721 behavior, and invoking it with any other value deactivates it.
8722
8723 ** Change in system-type and system-configuration values.
8724
8725 The value of system-type on a Linux-based GNU system is now `lignux',
8726 not `linux'. This means that some programs which use `system-type'
8727 need to be changed. The value of `system-configuration' will also
8728 be different.
8729
8730 It is generally recommended to use `system-configuration' rather
8731 than `system-type'.
8732
8733 See the file LINUX-GNU in this directory for more about this.
8734
8735 ** The functions shell-command and dired-call-process
8736 now run file name handlers for default-directory, if it has them.
8737
8738 ** Undoing the deletion of text now restores the positions of markers
8739 that pointed into or next to the deleted text.
8740
8741 ** Timers created with run-at-time now work internally to Emacs, and
8742 no longer use a separate process. Therefore, they now work more
8743 reliably and can be used for shorter time delays.
8744
8745 The new function run-with-timer is a convenient way to set up a timer
8746 to run a specified amount of time after the present. A call looks
8747 like this:
8748
8749 (run-with-timer SECS REPEAT FUNCTION ARGS...)
8750
8751 SECS says how many seconds should elapse before the timer happens.
8752 It may be an integer or a floating point number. When the timer
8753 becomes ripe, the action is to call FUNCTION with arguments ARGS.
8754
8755 REPEAT gives the interval for repeating the timer (measured in
8756 seconds). It may be an integer or a floating point number. nil or 0
8757 means don't repeat at all--call FUNCTION just once.
8758
8759 *** with-timeout provides an easy way to do something but give
8760 up if too much time passes.
8761
8762 (with-timeout (SECONDS TIMEOUT-FORMS...) BODY...)
8763
8764 This executes BODY, but gives up after SECONDS seconds.
8765 If it gives up, it runs the TIMEOUT-FORMS and returns the value
8766 of the last one of them. Normally it returns the value of the last
8767 form in BODY.
8768
8769 *** You can now arrange to call a function whenever Emacs is idle for
8770 a certain length of time. To do this, call run-with-idle-timer. A
8771 call looks like this:
8772
8773 (run-with-idle-timer SECS REPEAT FUNCTION ARGS...)
8774
8775 SECS says how many seconds of idleness should elapse before the timer
8776 runs. It may be an integer or a floating point number. When the
8777 timer becomes ripe, the action is to call FUNCTION with arguments
8778 ARGS.
8779
8780 Emacs becomes idle whenever it finishes executing a keyboard or mouse
8781 command. It remains idle until it receives another keyboard or mouse
8782 command.
8783
8784 REPEAT, if non-nil, means this timer should be activated again each
8785 time Emacs becomes idle and remains idle for SECS seconds The timer
8786 does not repeat if Emacs *remains* idle; it runs at most once after
8787 each time Emacs becomes idle.
8788
8789 If REPEAT is nil, the timer runs just once, the first time Emacs is
8790 idle for SECS seconds.
8791
8792 *** post-command-idle-hook is now obsolete; you shouldn't use it at
8793 all, because it interferes with the idle timer mechanism. If your
8794 programs use post-command-idle-hook, convert them to use idle timers
8795 instead.
8796
8797 *** y-or-n-p-with-timeout lets you ask a question but give up if
8798 there is no answer within a certain time.
8799
8800 (y-or-n-p-with-timeout PROMPT SECONDS DEFAULT-VALUE)
8801
8802 asks the question PROMPT (just like y-or-n-p). If the user answers
8803 within SECONDS seconds, it returns the answer that the user gave.
8804 Otherwise it gives up after SECONDS seconds, and returns DEFAULT-VALUE.
8805
8806 ** Minor change to `encode-time': you can now pass more than seven
8807 arguments. If you do that, the first six arguments have the usual
8808 meaning, the last argument is interpreted as the time zone, and the
8809 arguments in between are ignored.
8810
8811 This means that it works to use the list returned by `decode-time' as
8812 the list of arguments for `encode-time'.
8813
8814 ** The default value of load-path now includes the directory
8815 /usr/local/share/emacs/VERSION/site-lisp In addition to
8816 /usr/local/share/emacs/site-lisp. You can use this new directory for
8817 site-specific Lisp packages that belong with a particular Emacs
8818 version.
8819
8820 It is not unusual for a Lisp package that works well in one Emacs
8821 version to cause trouble in another. Sometimes packages need updating
8822 for incompatible changes; sometimes they look at internal data that
8823 has changed; sometimes the package has been installed in Emacs itself
8824 and the installed version should be used. Whatever the reason for the
8825 problem, this new feature makes it easier to solve.
8826
8827 ** When your program contains a fixed file name (like .completions or
8828 .abbrev.defs), the file name usually needs to be different on operating
8829 systems with limited file name syntax.
8830
8831 Now you can avoid ad-hoc conditionals by using the function
8832 convert-standard-filename to convert the file name to a proper form
8833 for each operating system. Here is an example of use, from the file
8834 completions.el:
8835
8836 (defvar save-completions-file-name
8837 (convert-standard-filename "~/.completions")
8838 "*The filename to save completions to.")
8839
8840 This sets the variable save-completions-file-name to a value that
8841 depends on the operating system, because the definition of
8842 convert-standard-filename depends on the operating system. On
8843 Unix-like systems, it returns the specified file name unchanged. On
8844 MS-DOS, it adapts the name to fit the limitations of that system.
8845
8846 ** The interactive spec N now returns the numeric prefix argument
8847 rather than the raw prefix argument. (It still reads a number using the
8848 minibuffer if there is no prefix argument at all.)
8849
8850 ** When a process is deleted, this no longer disconnects the process
8851 marker from its buffer position.
8852
8853 ** The variable garbage-collection-messages now controls whether
8854 Emacs displays a message at the beginning and end of garbage collection.
8855 The default is nil, meaning there are no messages.
8856
8857 ** The variable debug-ignored-errors specifies certain kinds of errors
8858 that should not enter the debugger. Its value is a list of error
8859 condition symbols and/or regular expressions. If the error has any
8860 of the condition symbols listed, or if any of the regular expressions
8861 matches the error message, then that error does not enter the debugger,
8862 regardless of the value of debug-on-error.
8863
8864 This variable is initialized to match certain common but uninteresting
8865 errors that happen often during editing.
8866
8867 ** The new function error-message-string converts an error datum
8868 into its error message. The error datum is what condition-case
8869 puts into the variable, to describe the error that happened.
8870
8871 ** Anything that changes which buffer appears in a given window
8872 now runs the window-scroll-functions for that window.
8873
8874 ** The new function get-buffer-window-list returns a list of windows displaying
8875 a buffer. The function is called with the buffer (a buffer object or a buffer
8876 name) and two optional arguments specifying the minibuffer windows and frames
8877 to search. Therefore this function takes optional args like next-window etc.,
8878 and not get-buffer-window.
8879
8880 ** buffer-substring now runs the hook buffer-access-fontify-functions,
8881 calling each function with two arguments--the range of the buffer
8882 being accessed. buffer-substring-no-properties does not call them.
8883
8884 If you use this feature, you should set the variable
8885 buffer-access-fontified-property to a non-nil symbol, which is a
8886 property name. Then, if all the characters in the buffer range have a
8887 non-nil value for that property, the buffer-access-fontify-functions
8888 are not called. When called, these functions should put a non-nil
8889 property on the text that they fontify, so that they won't get called
8890 over and over for the same text.
8891
8892 ** Changes in lisp-mnt.el
8893
8894 *** The lisp-mnt package can now recognize file headers that are written
8895 in the formats used by the `what' command and the RCS `ident' command:
8896
8897 ;; @(#) HEADER: text
8898 ;; $HEADER: text $
8899
8900 in addition to the normal
8901
8902 ;; HEADER: text
8903
8904 *** The commands lm-verify and lm-synopsis are now interactive. lm-verify
8905 checks that the library file has proper sections and headers, and
8906 lm-synopsis extracts first line "synopsis'"information.
8907
8908
8909 \f
8910 * For older news, see the file ONEWS
8911
8912 ----------------------------------------------------------------------
8913 Copyright information:
8914
8915 Copyright (C) 1999, 2000 Free Software Foundation, Inc.
8916
8917 Permission is granted to anyone to make or distribute verbatim copies
8918 of this document as received, in any medium, provided that the
8919 copyright notice and this permission notice are preserved,
8920 thus giving the recipient permission to redistribute in turn.
8921
8922 Permission is granted to distribute modified versions
8923 of this document, or of portions of it,
8924 under the above conditions, provided also that they
8925 carry prominent notices stating who last changed them.
8926 \f
8927 Local variables:
8928 mode: outline
8929 paragraph-separate: "[ \f]*$"
8930 end: