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