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