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