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