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1GNU Emacs NEWS -- history of user-visible changes. 5 Jan 2000
2Copyright (C) 1996, 1997, 1998, 1999, 2000 Free Software Foundation, Inc.
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3See the end for copying conditions.
4
5Please send Emacs bug reports to bug-gnu-emacs@gnu.org.
6For older news, see the file ONEWS.
7
8\f
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9* Installation Changes in Emacs 21.1
10
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11** `movemail' defaults to supporting POP. You can turn this off using
12the --without-pop configure option, should that be necessary.
13
14** There are new configure options associated with the support for
15images and toolkit scrollbars. Use the --help option to list them.
16\f
17* Changes in Emacs 21.1
18
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19** Emacs now refuses to load compiled Lisp files which weren't
20compiled with Emacs. Set `load-dangerous-libraries' to t to change
21this behavior.
22
23The reason for this change is an incompatible change in XEmacs' byte
24compiler. Files compiled with XEmacs can contain byte codes that let
25Emacs dump core.
26
27** New X resources recognized
100b3cbb 28
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29*** The X resource `synchronous', class `Synchronous', specifies
30whether Emacs should run in synchronous mode. Synchronous mode
31is useful for debugging X problems.
32
33Example:
34
699238d9 35 emacs.synchronous: true
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37*** The X resource `visualClass, class `VisualClass', specifies the
38visual Emacs should use. The resource's value should be a string of
39the form `CLASS-DEPTH', where CLASS is the name of the visual class,
40and DEPTH is the requested color depth as a decimal number. Valid
41visual class names are
42
43 TrueColor
44 PseudoColor
45 DirectColor
46 StaticColor
47 GrayScale
48 StaticGray
49
50Visual class names specified as X resource are case-insensitive, i.e.
51`pseudocolor', `Pseudocolor' and `PseudoColor' all have the same
52meaning.
53
54The program `xdpyinfo' can be used to list the visual classes
55supported on your display, and which depths they have. If
56`visualClass' is not specified, Emacs uses the display's default
57visual.
58
59Example:
60
699238d9 61 emacs.visualClass: TrueColor-8
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62
63*** The X resource `privateColormap', class `PrivateColormap',
64specifies that Emacs should use a private colormap if it is using the
65default visual, and that visual is of class PseudoColor. Recognized
66resource values are `true' or `on'.
67
68Example:
69
699238d9 70 emacs.privateColormap: true
100b3cbb 71
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72** The menu bar configuration has changed. The new configuration is
73more CUA-compliant. The most significant change is that Options is
74now a separate menu-bar item, with Mule and Customize as its submenus.
75
42088c12 76** User-option `show-cursor-in-non-selected-windows' controls how to
c60ea02e 77display the cursor in non-selected windows. If nil, no cursor is
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78shown, if non-nil a hollow box cursor is shown. This option can
79be customized.
c60ea02e 80
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81** The variable `echo-keystrokes' may now have a floating point value.
82
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83** C-x 5 1 runs the new command delete-other-frames which deletes
84all frames except the selected one.
85
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86** If your init file is compiled (.emacs.elc), `user-init-file' is set
87to the source name (.emacs.el), if that exists, after loading it.
88
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89** The help string specified for a menu-item whose definition contains
90the property `:help HELP' is now displayed under X either in the echo
91area or with tooltips.
92
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93** New user option `read-mail-command' specifies a command to use to
94read mail from the menu etc.
95
96** Changes in Outline mode.
97
98There is now support for Imenu to index headings. A new command
99`outline-headers-as-kill' copies the visible headings in the region to
100the kill ring, e.g. to produce a table of contents.
101
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102** New command M-x check-parens can be used to find unbalanced paren
103groups and strings in buffers in Lisp mode (or other modes).
104
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105** You can now easily create new *Info* buffers using either M-x clone-buffer
106or C-u m <entry> RET. M-x clone-buffer can also be used on *Help* and
107several other special buffers.
108
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109** Emacs can now support 'wheeled' mice (such as the MS IntelliMouse)
110under XFree86. To enable this, simply put (mwheel-install) in your
111.emacs file.
112
113The variables `mwheel-follow-mouse' and `mwheel-scroll-amount'
114determine where and by how much buffers are scrolled.
115
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116** Listing buffers with M-x list-buffers (C-x C-b) now shows
117abbreviated file names. Abbreviations can be customized by changing
118`directory-abbrev-alist'.
119
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120** Reading from the mini-buffer now reads from standard input if Emacs
121is running in batch mode. For example,
122
123 (message "%s" (read t))
124
125will read a Lisp expression from standard input and print the result
126to standard output.
127
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128** Faces and frame parameters.
129
130There are four new faces `scroll-bar', `border', `cursor' and `mouse'.
131Setting the frame parameters `scroll-bar-foreground' and
132`scroll-bar-background' sets foreground and background color of face
133`scroll-bar' and vice versa. Setting frame parameter `border-color'
134sets the background color of face `border' and vice versa. Likewise
135for frame parameters `cursor-color' and face `cursor', and frame
136parameter `mouse-color' and face `mouse'.
137
138Changing frame parameter `font' sets font-related attributes of the
139`default' face and vice versa. Setting frame parameters
79214ddf 140`foreground-color' or `background-color' sets the colors of the
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141`default' face and vice versa.
142
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143** New face `menu'.
144
145The face `menu' can be used to change colors and font of Emacs' menus.
146Setting the font of LessTif/Motif menus is currently not supported;
147attempts to set the font are ignored in this case.
148
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149** New frame parameter `screen-gamma' for gamma correction.
150
151The new frame parameter `screen-gamma' specifies gamma-correction for
152colors. Its value may be nil, the default, in which case no gamma
153correction occurs, or a number > 0, usually a float, that specifies
154the screen gamma of a frame's display.
155
156PC monitors usually have a screen gamma of 2.2. smaller values result
157in darker colors. You might want to try a screen gamma of 1.5 for LCD
158color displays. The viewing gamma Emacs uses is 0.4545. (1/2.2).
159
160The X resource name of this parameter is `screenGamma', class
161`ScreenGamma'.
162
163** Emacs has a new redisplay engine.
164
165The new redisplay handles characters of variable width and height.
166Italic text can be used without redisplay problems. Fonts containing
167oversized characters, i.e. characters larger than the logical height
168of a font can be used. Images of various formats can be displayed in
169the text.
170
171** Emacs has a new face implementation.
172
173The new faces no longer fundamentally use X font names to specify the
174font. Instead, each face has several independent attributes--family,
175height, width, weight and slant--that it may or may not specify.
176These attributes can be merged from various faces, and then together
177specify a font.
178
179Faces are supported on terminals that can display color or fonts.
180These terminal capabilities are auto-detected. Details can be found
181under Lisp changes, below.
182
183** New default font is Courier 12pt.
184
185** When using a windowing terminal, Emacs window now has a cursor of
186its own. When the window is selected, the cursor is solid; otherwise,
187it is hollow.
188
189** Bitmap areas to the left and right of windows are used to display
190truncation marks, continuation marks, overlay arrows and alike. The
191foreground, background, and stipple of these areas can be changed by
192customizing face `fringe'.
193
194** The mode line under X is now drawn with shadows by default. You
195can change its appearance by modifying the face `modeline'.
196
197** LessTif support.
198
199Emacs now runs with LessTif (see <http://www.lesstif.org>). You will
200need a version 0.88.1 or later.
201
202** Toolkit scroll bars.
203
204Emacs now uses toolkit scrollbars if available. When configured for
205LessTif/Motif, it will use that toolkit's scrollbar. Otherwise, when
206configured for Lucid and Athena widgets, it will use the Xaw3d scroll
207bar if Xaw3d is available. You can turn off the use of toolkit scroll
208bars by specifying `--with-toolkit-scroll-bars=no' when configuring
209Emacs.
210
211When you encounter problems with the Xaw3d scroll bar, watch out how
212Xaw3d is compiled on your system. If the Makefile generated from
213Xaw3d's Imakefile contains a `-DNARROWPROTO' compiler option, and your
214Emacs system configuration file `s/your-system.h' does not contain a
215define for NARROWPROTO, you might consider adding it. Take
216`s/freebsd.h' as an example.
217
218Alternatively, if you don't have access to the Xaw3d source code, take
219a look at your system's imake configuration file, for example in the
220directory `/usr/X11R6/lib/X11/config' (paths are different on
221different systems). You will find files `*.cf' there. If your
222system's cf-file contains a line like `#define NeedWidePrototypes NO',
223add a `#define NARROWPROTO' to your Emacs system configuration file.
224
225The reason for this is that one Xaw3d function uses `double' or
226`float' function parameters depending on the setting of NARROWPROTO.
227This is not a problem when Imakefiles are used because each system's
228image configuration file contains the necessary information. Since
229Emacs doesn't use imake, this has do be done manually.
230
231** Toggle buttons and radio buttons in menus.
232
233When compiled with LessTif (or Motif) support, Emacs uses toolkit
234widgets for radio and toggle buttons in menus. When configured for
235Lucid, Emacs draws radio buttons and toggle buttons similar to Motif.
236
237** Highlighting of trailing whitespace.
238
239When `show-trailing-whitespace' is non-nil, Emacs displays trailing
240whitespace in the face `trailing-whitespace'. Trailing whitespace is
241defined as spaces or tabs at the end of a line. To avoid busy
242highlighting when entering new text, trailing whitespace is not
243displayed if point is at the end of the line containing the
244whitespace.
245
246** Busy-cursor.
247
248Emacs can optionally display a busy-cursor under X. You can turn the
249display on or off by customizing group `cursor'.
250
251** Blinking cursor
252
253M-x blink-cursor-mode toggles a blinking cursor under X and on
254terminals having terminal capabilities `vi', `vs', and `ve'. Blinking
255and related parameters like frequency and delay can be customized in
256the group `cursor'.
257
258** New font-lock support mode `jit-lock-mode'.
259
260This support mode is roughly equivalent to `lazy-lock' but is
261generally faster. It supports stealth and deferred fontification.
262See the documentation of the function `jit-lock-mode' for more
263details.
264
265Font-lock uses jit-lock-mode as default support mode, so you don't
266have to do anything to activate it.
267
268** Tabs and variable-width text.
269
270Tabs are now displayed with stretch properties; the width of a tab is
271defined as a multiple of the normal character width of a frame, and is
272independent of the fonts used in the text where the tab appears.
273Thus, tabs can be used to line up text in different fonts.
274
275** Enhancements of the Lucid menu bar
276
277*** The Lucid menu bar now supports the resource "margin".
278
279 emacs.pane.menubar.margin: 5
280
281The default margin is 4 which makes the menu bar appear like the Motif
282one.
283
284*** Arrows that indicate sub-menus are now drawn with shadows, like in
285Motif.
286
287** Hscrolling in C code.
288
289Horizontal scrolling now happens automatically.
290
291** Tool bar support.
292
293Emacs supports a tool bar at the top of a frame under X. For details
294how to define a tool bar, see the page describing Lisp-level changes.
295
296** Mouse-sensitive mode line.
297
298Different parts of the mode line under X have been made
299mouse-sensitive. Moving the mouse to a mouse-sensitive part in the mode
300line changes the appearance of the mouse pointer to an arrow, and help
301about available mouse actions is displayed either in the echo area, or
302in the tooltip window if you have enabled one.
303
304Currently, the following actions have been defined:
305
306- Mouse-1 on the buffer name in the mode line switches between two
307buffers.
308
309- Mouse-2 on the buffer-name switches to the next buffer, and
310M-mouse-2 switches to the previous buffer in the buffer list.
311
312- Mouse-3 on the buffer-name displays a buffer menu.
313
559cee90 314- Mouse-2 on the read-only status in the mode line (`%' or `*')
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315toggles the read-only status.
316
317- Mouse-3 on the mode name display a minor-mode menu.
318
319** LessTif/Motif file selection dialog.
320
321When Emacs is configured to use LessTif or Motif, reading a file name
e33b0397 322from a menu will pop up a file selection dialog if `use-dialog-box' is
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323non-nil.
324
325** Emacs can display faces on TTY frames.
326
327Emacs automatically detects terminals that are able to display colors.
328Faces with a weight greater than normal are displayed extra-bright, if
329the terminal supports it. Faces with a weight less than normal and
330italic faces are displayed dimmed, if the terminal supports it.
331Underlined faces are displayed underlined if possible. Other face
332attributes like overlines, strike-throught, box are ignored.
333
334** Sound support
335
336Emacs supports playing sound files on GNU/Linux and the free BSDs
337(Voxware driver and native BSD driver, aka as Luigi's driver).
338Currently supported file formats are RIFF-WAVE (*.wav) and Sun Audio
339(*.au). You must configure Emacs with the option `--with-sound=yes'
340to enable sound support.
341
342** A new variable, backup-by-copying-when-privileged-mismatch, gives
343the highest file uid for which backup-by-copying-when-mismatch will be
344forced on. The assumption is that uids less than or equal to this
345value are special uids (root, bin, daemon, etc.--not real system
346users) and that files owned by these users should not change ownership,
347even if your system policy allows users other than root to edit them.
348
349The default is 200; set the variable to nil to disable the feature.
350
351** A block cursor can be drawn as wide as the glyph under it under X.
352
353As an example: if a block cursor is over a tab character, it will be
354drawn as wide as that tab on the display. To do this, set
355`x-stretch-cursor' to a non-nil value.
356
357** Empty display lines at the end of a buffer may be marked with a
358bitmap (this is similar to the tilde displayed by vi).
359
360This behavior is activated by setting the buffer-local variable
361`indicate-empty-lines' to a non-nil value. The default value of this
362variable is found in `default-indicate-empty-lines'.
363
364** There is a new "aggressive" scrolling method.
365
366When scrolling up because point is above the window start, if the
367value of the buffer-local variable `scroll-up-aggessively' is a
368number, Emacs chooses a new window start so that point ends up that
369fraction of the window's height from the bottom of the window.
370
371When scrolling down because point is below the window end, if the
372value of the buffer-local variable `scroll-down-aggessively' is a
373number, Emacs chooses a new window start so that point ends up that
374fraction of the window's height from the top of the window.
375
376** The rectangle commands now avoid inserting undesirable spaces,
377notably at the end of lines.
378
379All these functions have been rewritten to avoid inserting unwanted
380spaces, and an optional prefix now allows them to behave the old way.
381
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382There is a new command M-x replace-rectangle.
383
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384** The new command M-x query-replace-regexp-eval acts like
385query-replace-regexp, but takes a Lisp expression which is evaluated
386after each match to get the replacement text.
387
388** Emacs now resizes mini-windows if appropriate.
389
390If a message is longer than one line, or mini-buffer contents are
391longer than one line, Emacs now resizes the mini-window unless it is
392on a frame of its own. You can control the maximum mini-window size
393by setting the following variable:
394
395- User option: max-mini-window-height
396
397Maximum height for resizing mini-windows. If a float, it specifies a
398fraction of the mini-window frame's height. If an integer, it
399specifies a number of lines. If nil, don't resize.
400
401Default is 0.25.
402
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403** Changes to hideshow.el
404
405Hideshow is now at version 5.x. It uses a new algorithms for block
406selection and traversal and includes more isearch support.
407
408*** Generalized block selection and traversal
409
410A block is now recognized by three things: its start and end regexps
411(both strings), and a match-data selector (an integer) specifying
412which sub-expression in the start regexp serves as the place where a
413`forward-sexp'-like function can operate. Hideshow always adjusts
414point to this sub-expression before calling `hs-forward-sexp-func'
415(which for most modes evaluates to `forward-sexp').
416
417If the match-data selector is not specified, it defaults to zero,
418i.e., the entire start regexp is valid, w/ no prefix. This is
419backwards compatible with previous versions of hideshow. Please see
420the docstring for variable `hs-special-modes-alist' for details.
421
422*** Isearch support for updating mode line
423
424During incremental search, if Hideshow minor mode is active, hidden
425blocks are temporarily shown. The variable `hs-headline' records the
426line at the beginning of the opened block (preceding the hidden
427portion of the buffer), and the mode line is refreshed. When a block
428is re-hidden, the variable is set to nil.
429
430To show `hs-headline' in the mode line, you may wish to include
431something like this in your .emacs.
432
433 (add-hook 'hs-minor-mode-hook
434 (lambda ()
435 (add-to-list 'mode-line-format 'hs-headline)))
436
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437** Changes to Change Log mode and Add-Log functions
438
439If you invoke `add-change-log-entry' from a backup file, it makes an
440entry appropriate for the file's parent. This is useful for making
441log entries by comparing a version with deleted functions.
442
443New command M-x change-log-merge merges another log into the current
444buffer, fixing old-style date formats if necessary.
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445
446Change Log mode now adds a file's version number to change log entries
447if user-option `change-log-version-info-enabled' is non-nil.
448
449The search for a file's version number is performed based on regular
450expressions from `change-log-version-number-regexp-list' which can be
451cutomized. Version numbers are only found in the first 10 percent of
452a file.
453
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454** Changes in Font Lock
455
456*** The new function `font-lock-remove-keywords' can be used to remove
457font-lock keywords from the current buffer or from a specific major
458mode.
459
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460** Comint (subshell) changes
461
462Comint now includes new features to send commands to running processes
463and redirect the output to a designated buffer or buffers.
464
465The command M-x comint-redirect-send-command reads a command and
466buffer name from the mini-buffer. The command is sent to the current
467buffer's process, and its output is inserted into the specified buffer.
468
469The command M-x comint-redirect-send-command-to-process acts like
470M-x comint-redirect-send-command but additionally reads the name of
471the buffer whose process should be used from the mini-buffer.
472
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473** Changes to Rmail mode
474
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475*** The new user-option rmail-confirm-expunge controls whether and how
476to ask for confirmation before expunging deleted messages from an
477Rmail file. You can choose between no confirmation, confirmation
478with y-or-n-p, or confirmation with yes-or-no-p. Default is to ask
479for confirmation with yes-or-no-p.
480
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481*** RET is now bound in the Rmail summary to rmail-summary-goto-msg,
482like `j'.
483
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484*** There is a new user option `rmail-digest-end-regexps' that
485specifies the regular expressions to detect the line that ends a
2d5e9b54 486digest message.
e26cec67 487
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488** Changes to TeX mode
489
490The default mode has been changed from `plain-tex-mode' to
491`latex-mode'.
492
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493** Changes to RefTeX mode
494
495*** RefTeX has new support for index generation. Index entries can be
496 created with `C-c <', with completion available on index keys.
497 Pressing `C-c /' indexes the word at the cursor with a default
498 macro. `C-c >' compiles all index entries into an alphabetically
499 sorted *Index* buffer which looks like the final index. Entries
500 can be edited from that buffer.
501
502*** Label and citation key selection now allow to select several
503 items and reference them together (use `m' to mark items, `a' or
504 `A' to use all marked entries).
505
506*** reftex.el has been split into a number of smaller files to reduce
507 memory use when only a part of RefTeX is being used.
508
509*** a new command `reftex-view-crossref-from-bibtex' (bound to `C-c &'
510 in BibTeX-mode) can be called in a BibTeX database buffer in order
511 to show locations in LaTeX documents where a particular entry has
512 been cited.
513
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514** Emacs Lisp mode now allows multiple levels of outline headings.
515The level of a heading is determined from the number of leading
516semicolons in a heading line. Toplevel forms starting with a `('
517in column 1 are always made leaves.
518
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519** The M-x time-stamp command (most commonly used on write-file-hooks)
520has the following new features:
521
522*** The patterns for finding the time stamp and for updating a pattern
523may match text spanning multiple lines. For example, some people like
524to have the filename and date on separate lines. The new variable
525time-stamp-inserts-lines controls the matching for multi-line patterns.
526
527*** More than one time stamp can be updated in the same file. This
528feature is useful if you need separate time stamps in a program source
529file to both include in formatted documentation and insert in the
530compiled binary. The same time-stamp will be written at each matching
531pattern. The variable time-stamp-count enables this new feature; it
532defaults to 1.
533
534** Tooltips.
535
536Tooltips are small X windows displaying a help string at the current
537mouse position. To use them, use the Lisp package `tooltip' which you
538can access via the user option `tooltip-mode'.
539
540Tooltips also provides support for GUD debugging. If activated,
541variable values can be displayed in tooltips by pointing at them with
542the mouse in source buffers. You can customize various aspects of the
543tooltip display in the group `tooltip'.
544
545** Customize changes
546
547*** Customize now supports comments about customized items. Use the
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548`State' menu to add comments. Note that customization comments will
549cause the customizations to fail in earlier versions of Emacs.
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550
551*** The new option `custom-buffer-done-function' says whether to kill
552Custom buffers when you've done with them or just bury them (the
553default).
554
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555*** The keyword :set-after in defcustom allows to specify dependencies
556between custom options. Example:
557
558 (defcustom default-input-method nil
559 "*Default input method for multilingual text (a string).
560 This is the input method activated automatically by the command
561 `toggle-input-method' (\\[toggle-input-method])."
562 :group 'mule
563 :type '(choice (const nil) string)
564 :set-after '(current-language-environment))
565
566This specifies that default-input-method should be set after
567current-language-environment even if default-input-method appears
568first in a custom-set-variables statement.
569
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570** New features in evaluation commands
571
572The commands to evaluate Lisp expressions, such as C-M-x in Lisp
573modes, C-j in Lisp Interaction mode, and M-:, now bind the variables
574print-level, print-length, and debug-on-error based on the
575customizable variables eval-expression-print-level,
576eval-expression-print-length, and eval-expression-debug-on-error.
577
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578** Dired changes
579
580*** New variable `dired-recursive-deletes' determines if the delete
581command will delete non-empty directories recursively. The default
582is, delete only empty directories.
583
584*** New variable `dired-recursive-copies' determines if the copy
585command will copy directories recursively. The default is, do not
586copy directories recursively.
587
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588*** In command `dired-do-shell-command' (usually bound to `!') a `?'
589in the shell command has a special meaning similar to `*', but with
590the difference that the command will be run on each file individually.
591
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592** The variable mail-specify-envelope-from controls whether to
593use the -f option when sending mail.
594
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595** CC mode changes.
596
597Note: This release contains changes that might not be compatible with
598current user setups (although it's believed that these
599incompatibilities will only show in very uncommon circumstances).
600However, since the impact is uncertain, these changes may be rolled
601back depending on user feedback. Therefore there's no forward
602compatibility guarantee wrt the new features introduced in this
603release.
604
605*** New initialization procedure for the style system.
606When the initial style for a buffer is determined by CC Mode (from the
607variable c-default-style), the global values of style variables now
608take precedence over the values specified by the chosen style. This
609is different than the old behavior: previously, the style-specific
610settings would override the global settings. This change makes it
611possible to do simple configuration in the intuitive way with
612Customize or with setq lines in one's .emacs file.
613
614By default, the global value of every style variable is the new
615special symbol set-from-style, which causes the value to be taken from
616the style system. This means that in effect, only an explicit setting
617of a style variable will cause the "overriding" behavior described
618above.
619
620Also note that global settings override style-specific settings *only*
621when the initial style of a buffer is chosen by a CC Mode major mode
622function. When a style is chosen in other ways --- for example, by a
623call like (c-set-style "gnu") in a hook, or via M-x c-set-style ---
624then the style-specific values take precedence over any global style
625values. In Lisp terms, global values override style-specific values
626only when the new second argument to c-set-style is non-nil; see the
627function documentation for more info.
628
629The purpose of these changes is to make it easier for users,
630especially novice users, to do simple customizations with Customize or
631with setq in their .emacs files. On the other hand, the new system is
632intended to be compatible with advanced users' customizations as well,
633such as those that choose styles in hooks or whatnot. This new system
634is believed to be almost entirely compatible with current
635configurations, in spite of the changed precedence between style and
636global variable settings when a buffer's default style is set.
637
638(Thanks to Eric Eide for clarifying this explanation a bit.)
639
640**** c-offsets-alist is now a customizable variable.
641This became possible as a result of the new initialization behavior.
642
643This variable is treated slightly differently from the other style
644variables; instead of using the symbol set-from-style, it will be
645completed with the syntactic symbols it doesn't already contain when
646the style is first initialized. This means it now defaults to the
647empty list to make all syntactic elements get their values from the
648style system.
649
650**** Compatibility variable to restore the old behavior.
651In case your configuration doesn't work with this change, you can set
652c-old-style-variable-behavior to non-nil to get the old behavior back
653as far as possible.
654
655*** Improvements to line breaking and text filling.
656CC Mode now handles this more intelligently and seamlessly wrt the
657surrounding code, especially inside comments. For details see the new
658chapter about this in the manual.
659
660**** New variable to recognize comment line prefix decorations.
661The variable c-comment-prefix-regexp has been added to properly
662recognize the line prefix in both block and line comments. It's
663primarily used to initialize the various paragraph recognition and
664adaptive filling variables that the text handling functions uses.
665
666**** New variable c-block-comment-prefix.
667This is a generalization of the now obsolete variable
668c-comment-continuation-stars to handle arbitrary strings.
669
670**** CC Mode now uses adaptive fill mode.
671This to make it adapt better to the paragraph style inside comments.
672
673It's also possible to use other adaptive filling packages inside CC
674Mode, notably Kyle E. Jones' Filladapt mode (http://wonderworks.com/).
675A new convenience function c-setup-filladapt sets up Filladapt for use
676inside CC Mode.
677
678Note though that the 2.12 version of Filladapt lacks a feature that
679causes it to work suboptimally when c-comment-prefix-regexp can match
680the empty string (which it commonly does). A patch for that is
681available from the CC Mode web site (http://www.python.org/emacs/
682cc-mode/).
683
684**** It's now possible to selectively turn off auto filling.
685The variable c-ignore-auto-fill is used to ignore auto fill mode in
686specific contexts, e.g. in preprocessor directives and in string
687literals.
688
689**** New context sensitive line break function c-context-line-break.
690It works like newline-and-indent in normal code, and adapts the line
691prefix according to the comment style when used inside comments. If
692you're normally using newline-and-indent, you might want to switch to
693this function.
694
695*** Fixes to IDL mode.
696It now does a better job in recognizing only the constructs relevant
697to IDL. E.g. it no longer matches "class" as the beginning of a
698struct block, but it does match the CORBA 2.3 "valuetype" keyword.
699Thanks to Eric Eide.
700
701*** Improvements to the Whitesmith style.
702It now keeps the style consistently on all levels and both when
703opening braces hangs and when they don't.
704
705**** New lineup function c-lineup-whitesmith-in-block.
706
707*** New lineup functions c-lineup-template-args and c-indent-multi-line-block.
708See their docstrings for details. c-lineup-template-args does a
709better job of tracking the brackets used as parens in C++ templates,
710and is used by default to line up continued template arguments.
711
712*** c-lineup-comment now preserves alignment with a comment on the
713previous line. It used to instead preserve comments that started in
714the column specified by comment-column.
715
716*** c-lineup-C-comments handles "free form" text comments.
717In comments with a long delimiter line at the start, the indentation
718is kept unchanged for lines that start with an empty comment line
719prefix. This is intended for the type of large block comments that
720contain documentation with its own formatting. In these you normally
721don't want CC Mode to change the indentation.
722
723*** The `c' syntactic symbol is now relative to the comment start
724instead of the previous line, to make integers usable as lineup
725arguments.
726
727*** All lineup functions have gotten docstrings.
728
729*** More preprocessor directive movement functions.
730c-down-conditional does the reverse of c-up-conditional.
731c-up-conditional-with-else and c-down-conditional-with-else are
732variants of these that also stops at "#else" lines (suggested by Don
733Provan).
734
735*** Minor improvements to many movement functions in tricky situations.
736
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GM
737** Isearch changes
738
739*** In Isearch mode, mouse-2 in the echo area now yanks the current
a933dad1
DL
740selection into the search string rather than giving an error.
741
87be76f6
GM
742*** There is a new lazy highlighting feature in incremental search.
743
d35fce81 744Lazy highlighting is switched on/off by customizing variable
87be76f6
GM
745`isearch-lazy-highlight'. When active, all matches for the current
746search string are highlighted. The current match is highlighted as
747before using face `isearch' or `region'. All other matches are
748highlighted using face `isearch-lazy-highlight-face' which defaults to
749`secondary-selection'.
750
751The extra highlighting makes it easier to anticipate where the cursor
752will end up each time you press C-s or C-r to repeat a pending search.
753Highlighting of these additional matches happens in a deferred fashion
754using "idle timers," so the cycles needed do not rob isearch of its
755usual snappy response.
756
757If `isearch-lazy-highlight-cleanup' is set to t, highlights for
758matches are automatically cleared when you end the search. If it is
759set to nil, you can remove the highlights manually with `M-x
760isearch-lazy-highlight-cleanup'.
761
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762** Changes in sort.el
763
764The function sort-numeric-fields interprets numbers starting with `0'
12c25bdc 765as octal and numbers starting with `0x' or `0X' as hexadecimal. The
35384f06
GM
766new user-option sort-numberic-base can be used to specify a default
767numeric base.
87be76f6 768
d7b511c4
GM
769** Changes to Ange-ftp
770
771*** Ange-ftp allows you to specify of a port number in remote file
d67f47e4
DL
772names cleanly. It is appended to the host name, separated by a hash
773sign, e.g. `/foo@bar.org#666:mumble'. (This syntax comes from EFS.)
774
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GM
775*** If the new user-option `ange-ftp-try-passive-mode' is set, passive
776ftp mode will be used if the ftp client supports that.
777
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GM
778** Shell script mode changes.
779
780Shell script mode (sh-script) can now indent scripts for shells
781derived from sh and rc. The indentation style is customizeable, and
782sh-script can attempt to "learn" the current buffer's style.
783
79214ddf
FP
784** Etags changes.
785
786*** In DOS, etags looks for file.cgz if it cannot find file.c.
787
aca0be23 788*** New option --ignore-case-regex is an alternative to --regex. It is now
8dc78b52
FP
789possible to bind a regexp to a language, by prepending the regexp with
790{lang}, where lang is one of the languages that `etags --help' prints out.
791This feature is useful especially for regex files, where each line contains
792a regular expression. The manual contains details.
aca0be23 793
79214ddf
FP
794*** In C and derived languages, etags creates tags for function
795declarations when given the --declarations option.
796
797*** In C++, tags are created for "operator". The tags have the form
aca0be23 798"operator+", without spaces between the keyword and the operator.
79214ddf
FP
799
800*** New language Ada: tags are functions, procedures, packages, tasks, and
801types.
802
803*** In Fortran, procedure is no more tagged.
804
805*** In Java, tags are created for "interface".
806
807*** In Lisp, "(defstruct (foo", "(defun (operator" and similar constructs
808are now tagged.
809
810*** In Perl, the --globals option tags global variables. my and local
811variables are tagged.
812
813*** New language Python: def and class at the beginning of a line are tags.
814
8dc78b52
FP
815*** .ss files are Scheme files, .pdb is Postscript with C syntax, .psw is
816for PSWrap.
79214ddf 817
f6737cde
GM
818** Changes in etags.el
819
3f6e4b8b
GM
820*** The new user-option tags-case-fold-search can be used to make
821tags operations case-sensitive or case-insensitive. The default
822is to use the same setting as case-fold-search.
823
f6737cde
GM
824*** You can display additional output with M-x tags-apropos by setting
825the new variable tags-apropos-additional-actions.
826
827If non-nil, the variable's value should be a list of triples (TITLE
828FUNCTION TO-SEARCH). For each triple, M-x tags-apropos processes
829TO-SEARCH and lists tags from it. TO-SEARCH should be an alist,
830obarray, or symbol. If it is a symbol, the symbol's value is used.
831
832TITLE is a string to use to label the list of tags from TO-SEARCH.
833
834FUNCTION is a function to call when an entry is selected in the Tags
835List buffer. It is called with one argument, the selected symbol.
836
837A useful example value for this variable might be something like:
838
839 '(("Emacs Lisp" Info-goto-emacs-command-node obarray)
840 ("Common Lisp" common-lisp-hyperspec common-lisp-hyperspec-obarray)
841 ("SCWM" scwm-documentation scwm-obarray))
842
843*** The face tags-tag-face can be used to customize the appearance
844of tags in the output of M-x tags-apropos.
845
846*** Setting tags-apropos-verbose to a non-nil value displays the
847names of tags files in the *Tags List* buffer.
848
fbc164de
PE
849** Emacs now attempts to determine the initial language environment
850and preferred and locale coding systems systematically from the
851LC_ALL, LC_CTYPE, and LANG environment variables during startup.
852
59c1bf85
DL
853** New language environments `Latin-8' and `Latin-9'.
854These correspond respectively to the ISO character sets 8859-14
855(Celtic) and 8859-15 (updated Latin-1, with the Euro sign). There is
856currently no specific input method support for them.
857
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DL
858** Fortran mode has a new command `fortran-strip-sqeuence-nos' to
859remove text past column 72. The syntax class of `\' in Fortran is now
860appropriate for C-style escape sequences in strings.
861
862** SGML mode's default `sgml-validate-command' is now `nsgmls'.
863
6f8ea2ae
DL
864** A new command `view-emacs-problems' (C-h P) displays the PROBLEMS file.
865
a933dad1
DL
866** New modes and packages
867
5e5dff44
GM
868*** The new command M-x re-builder offers a convenient interface for
869authoring regular expressions with immediate visual feedback.
870
871The buffer from which the command was called becomes the target for
872the regexp editor popping up in a separate window. Matching text in
873the target buffer is immediately color marked during the editing.
874Each sub-expression of the regexp will show up in a different face so
875even complex regexps can be edited and verified on target data in a
876single step.
877
878On displays not supporting faces the matches instead blink like
879matching parens to make them stand out. On such a setup you will
880probably also want to use the sub-expression mode when the regexp
881contains such to get feedback about their respective limits.
882
f7136ee8
GM
883*** glasses-mode is a minor mode that makes
884unreadableIdentifiersLikeThis readable. It works as glasses, without
885actually modifying content of a buffer.
886
bbd9b566
GM
887*** The package ebnf2ps translates an EBNF to a syntactic chart in
888PostScript.
889
890Currently accepts ad-hoc EBNF, ISO EBNF and Bison/Yacc.
891
892The ad-hoc default EBNF syntax has the following elements:
893
894 ; comment (until end of line)
895 A non-terminal
896 "C" terminal
897 ?C? special
898 $A default non-terminal
899 $"C" default terminal
900 $?C? default special
901 A = B. production (A is the header and B the body)
902 C D sequence (C occurs before D)
903 C | D alternative (C or D occurs)
904 A - B exception (A excluding B, B without any non-terminal)
905 n * A repetition (A repeats n (integer) times)
906 (C) group (expression C is grouped together)
907 [C] optional (C may or not occurs)
908 C+ one or more occurrences of C
909 {C}+ one or more occurrences of C
910 {C}* zero or more occurrences of C
911 {C} zero or more occurrences of C
912 C / D equivalent to: C {D C}*
913 {C || D}+ equivalent to: C {D C}*
914 {C || D}* equivalent to: [C {D C}*]
915 {C || D} equivalent to: [C {D C}*]
916
917Please, see ebnf2ps documentation for EBNF syntax and how to use it.
918
99453a38
GM
919*** The package align.el will align columns within a region, using M-x
920align. Its mode-specific rules, based on regular expressions,
921determine where the columns should be split. In C and C++, for
922example, it will align variable names in declaration lists, or the
923equal signs of assignments.
924
559cee90
DL
925*** `paragraph-indent-minor-mode' is a new minor mode supporting
926paragraphs in the same style as `paragraph-indent-text-mode'.
927
6448a6b3
GM
928*** bs.el is a new package for buffer selection similar to
929list-buffers or electric-buffer-list. Use M-x bs-show to display a
930buffer menu with this package. You can use M-x bs-customize to
931customize the package.
932
249652b1
GM
933*** calculator.el is a small calculator package that is intended to
934replace desktop calculators such as xcalc and calc.exe. Actually, it
935is not too small - it has more features than most desktop calculators,
936and can be customized easily to get many more functions. It should
937not be confused with "calc" which is a much bigger mathematical tool
938which answers different needs.
939
3476b54a
GM
940*** The minor modes cwarn-mode and global-cwarn-mode highlights
941suspicious C and C++ constructions. Currently, assignments inside
942expressions, semicolon following `if', `for' and `while' (except, of
943course, after a `do .. while' statement), and C++ functions with
944reference parameters are recognized. The modes require font-lock mode
945to be enabled.
946
8964fec7
SM
947*** smerge-mode.el provides `smerge-mode', a simple minor-mode for files
948containing diff3-style conflict markers, such as generated by RCS.
949
a933dad1
DL
950*** 5x5.el is a simple puzzle game.
951
952*** hl-line.el provides a minor mode to highlight the current line.
953
954*** ansi-color.el translates ANSI terminal escapes into text-properties.
955
956*** delphi.el provides a major mode for editing the Delphi (Object
957Pascal) language.
958
959*** quickurl.el provides a simple method of inserting a URL based on
960the text at point.
961
962*** sql.el provides an interface to SQL data bases.
963
8d54eb69
DL
964*** fortune.el uses the fortune program to create mail/news signatures.
965
a933dad1
DL
966*** whitespace.el ???
967
ebcfda83
GM
968*** PostScript mode (ps-mode) is a new major mode for editing PostScript
969files. It offers: interaction with a PostScript interpreter, including
970(very basic) error handling; fontification, easily customizable for
971interpreter messages; auto-indentation; insertion of EPSF templates and
972often used code snippets; viewing of BoundingBox; commenting out /
973uncommenting regions; conversion of 8bit characters to PostScript octal
974codes. All functionality is accessible through a menu.
975
976*** delim-col helps to prettify columns in a text region or rectangle.
977
978Here is an example of columns:
979
980horse apple bus
981dog pineapple car EXTRA
982porcupine strawberry airplane
983
984Doing the following settings:
985
986 (setq delimit-columns-str-before "[ ")
987 (setq delimit-columns-str-after " ]")
988 (setq delimit-columns-str-separator ", ")
989 (setq delimit-columns-separator "\t")
990
991
992Selecting the lines above and typing:
993
994 M-x delimit-columns-region
995
996It results:
997
998[ horse , apple , bus , ]
999[ dog , pineapple , car , EXTRA ]
1000[ porcupine, strawberry, airplane, ]
1001
1002delim-col has the following options:
1003
1004 delimit-columns-str-before Specify a string to be inserted
1005 before all columns.
1006
1007 delimit-columns-str-separator Specify a string to be inserted
1008 between each column.
1009
1010 delimit-columns-str-after Specify a string to be inserted
1011 after all columns.
1012
1013 delimit-columns-separator Specify a regexp which separates
1014 each column.
1015
1016delim-col has the following commands:
1017
1018 delimit-columns-region Prettify all columns in a text region.
1019 delimit-columns-rectangle Prettify all columns in a text rectangle.
1020
f507826c
GM
1021*** The package recentf.el maintains a menu for visiting files that
1022were operated on recently. When enabled, a new "Open Recent" submenu
1023is displayed in the "Files" menu.
1024
1025The recent files list is automatically saved across Emacs sessions.
1026
1027To enable/disable recentf use M-x recentf-mode.
1028
1029To enable recentf at Emacs startup use
1030M-x customize-variable RET recentf-mode RET.
1031
1032To change the number of recent files displayed and others options use
1033M-x customize-group RET recentf RET.
1034
8062f458
DL
1035*** elide-head.el provides a mechanism for eliding boilerplate header
1036text.
1037
36e24b82 1038*** footnote.el provides `footnote-mode', a minor mode supporting use
91735437
DL
1039of footnotes. It is intended for use with Message mode, but isn't
1040specific to Message mode.
1041
36e24b82
DL
1042*** diff-mode.el provides `diff-mode', a major mode for
1043viewing/editing context diffs (patches). It is selected for files
1044with extension `.diff', `.diffs', `.patch' and `.rej'.
1045
aaa659ef
DL
1046*** EUDC, the Emacs Unified Directory Client, provides a common user
1047interface to access directory servers using different directory
1048protocols. It has a separate manual.
1049
eee54b0e
DL
1050*** autoconf.el provides a major mode for editing configure.in files
1051for Autoconf, selected automatically.
1052
aaa659ef
DL
1053*** windmove.el
1054
a933dad1
DL
1055** Withdrawn packages
1056
1057*** mldrag.el has been removed. mouse.el provides the same
1058functionality with aliases for the mldrag functions.
25a81338 1059
3261c1d8
DL
1060*** eval-reg.el has been obsoleted by changes to edebug.el and removed.
1061
1062*** ph.el has been obsoleted by EUDC and removed.
a933dad1
DL
1063\f
1064* Lisp changes in Emacs 21.1 (see following page for display-related features)
1065
1066Note that +++ before an item means the Lisp manual has been updated.
1067--- means that I have decided it does not need to be in the Lisp manual.
1068When you add a new item, please add it without either +++ or ---
1069so I will know I still need to look at it -- rms.
1070
19d1bc27
GM
1071*** The buffer-local variable cursor-type can be used to specify the
1072cursor to use in windows displaying a buffer. Values are interpreted
1073as follows:
1074
1075 t use the cursor specified for the frame (default)
1076 nil don't display a cursor
1077 `bar' display a bar cursor with default width
1078 (bar . WIDTH) display a bar cursor with width WIDTH
1079 others display a box cursor.
1080
9a0dd3dc
GM
1081** The variable open-paren-in-column-0-is-defun-start controls whether
1082an open parenthesis in column 0 is considered to be the start of a
1083defun. If set, the default, it is considered a defun start. If not
1084set, an open parenthesis in column 0 has no special meaning.
1085
d7b511c4
GM
1086** The new function `string-to-syntax' can be used to translate syntax
1087specificationa in string form as accepted my `modify-syntax-entry' to
1088the cons-cell form that is used for the values of the `syntax-table'
1089text property, and in `font-lock-syntactic-keywords'.
1090
1091Example:
1092
1093 (string-to-syntax "()")
1094 => (4 . 41)
1095
1fa28578
GM
1096** Emacs' reader supports CL read syntax for integers in bases
1097other than 10.
1098
1099*** `#BINTEGER' or `#bINTEGER' reads INTEGER in binary (radix 2).
1100INTEGER optionally contains a sign.
1101
1102 #b1111
1103 => 15
1104 #b-1111
1105 => -15
1106
1107*** `#OINTEGER' or `#oINTEGER' reads INTEGER in octal (radix 8).
1108
1109 #o666
1110 => 438
1111
1112*** `#XINTEGER' or `#xINTEGER' reads INTEGER in hexadecimal (radix 16).
1113
1114 #xbeef
1115 => 48815
1116
1117*** `#RADIXrINTEGER' reads INTEGER in radix RADIX, 2 <= RADIX <= 36.
1118
1119 #2R-111
1120 => -7
1121 #25rah
1122 => 267
1123
3d4ff2dd 1124** The function `documentation-property' now evaluates the value of
e9b4e5ff
GM
1125the given property to obtain a a string if it doesn't refer to etc/DOC
1126and isn't a string.
1127
3d4ff2dd
GM
1128** If called for a symbol, the function `documentation' now looks for
1129a `function-documentation' property of that symbol. If it has a non-nil
1130value, the documentation is taken from that value. If the value is
1131not a string, it is evaluated to obtain a string.
1132
16ce590d
DL
1133+++
1134** The last argument of `define-key-after' defaults to t for convenience.
1135
73825616 1136** The new function `replace-regexp-in-string' replaces all matches
16ce590d
DL
1137for a regexp in a string.
1138
1139** `mouse-position' now runs the abnormal hook
1140`mouse-position-function'.
1141
723e779c
GM
1142** The function string-to-number now returns a float for numbers
1143that don't fit into a Lisp integer.
1144
d1e103b2
GM
1145** The variable keyword-symbols-constants-flag has been removed.
1146Keywords are now always considered constants.
1147
31047e0d
DL
1148+++
1149** The new function `delete-and-extract-region' deletes text and
1150returns it.
1151
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GM
1152** The function `clear-this-command-keys' now also clears the vector
1153returned by function `recent-keys'.
1154
02b14400
RS
1155+++
1156** Variables `beginning-of-defun-function' and `end-of-defun-function'
1157can be used to define handlers for the functions that find defuns.
1158Major modes can define these locally instead of rebinding M-C-a
1159etc. if the normal conventions for defuns are not appropriate for the
1160mode.
404fa7d6 1161
02b14400 1162+++
8964fec7
SM
1163** easy-mmode-define-minor-mode now takes an additional BODY argument
1164and is renamed `define-minor-mode'.
1165
02b14400
RS
1166+++
1167** If an abbrev has a hook function which is a symbol, and that symbol
1168has a non-nil `no-self-insert' property, the return value of the hook
1169function specifies whether an expansion has been done or not. If it
1170returns nil, abbrev-expand also returns nil, meaning "no expansion has
1171been performed."
1172
1173When abbrev expansion is done by typing a self-inserting character,
1174and the abbrev has a hook with the `no-self-insert' property, and the
1175hook function returns non-nil meaning expansion has been done,
1176then the self-inserting character is not inserted.
ef961722 1177
02b14400 1178+++
81da8b32
GM
1179** The function `intern-soft' now accepts a symbol as first argument.
1180In this case, that exact symbol is looked up in the specified obarray,
1181and the function's value is nil if it is not found.
1182
02b14400 1183+++
9e207b90
GM
1184** The new macro `with-syntax-table' can be used to evaluate forms
1185with the syntax table of the current buffer temporarily set to a
1186specified table.
1187
1188 (with-syntax-table TABLE &rest BODY)
1189
1190Evaluate BODY with syntax table of current buffer set to a copy of
03d9c64c
GM
1191TABLE. The current syntax table is saved, BODY is evaluated, and the
1192saved table is restored, even in case of an abnormal exit. Value is
1193what BODY returns.
9e207b90 1194
02b14400 1195+++
d7f89643 1196** Regular expressions now support intervals \{n,m\} as well as
95cd4c40 1197Perl's shy-groups \(?:...\) and non-greedy *? +? and ?? operators.
8964fec7 1198
02b14400 1199+++
dde9e75a
GM
1200** The optional argument BUFFER of function file-local-copy has been
1201removed since it wasn't used by anything.
1202
02b14400 1203+++
9da30515
GM
1204** The file name argument of function `file-locked-p' is now required
1205instead of being optional.
1206
02b14400 1207+++
d20679eb
GM
1208** The new built-in error `text-read-only' is signaled when trying to
1209modify read-only text.
1210
02b14400 1211+++
fbc164de
PE
1212** New functions and variables for locales.
1213
1214The new variable `locale-coding-system' specifies how to encode and
1215decode strings passed to low-level message functions like strerror and
b718982a
PE
1216time functions like strftime. The new variables
1217`system-messages-locale' and `system-time-locale' give the system
1218locales to be used when invoking these two types of functions.
fbc164de
PE
1219
1220The new function `set-locale-environment' sets the language
1221environment, preferred coding system, and locale coding system from
1222the system locale as specified by the LC_ALL, LC_CTYPE, and LANG
b718982a
PE
1223environment variables. Normally, it is invoked during startup and need
1224not be invoked thereafter. It uses the new variables
1225`locale-language-names', `locale-charset-language-names', and
1226`locale-preferred-coding-systems' to make its decisions.
fbc164de 1227
02b14400 1228+++
863476d1
SM
1229** syntax tables now understand nested comments.
1230To declare a comment syntax as allowing nesting, just add an `n'
1231modifier to either of the characters of the comment end and the comment
1232start sequences.
1233
02b14400 1234+++
ef6d912c
GM
1235** The function `pixmap-spec-p' has been renamed `bitmap-spec-p'
1236because `bitmap' is more in line with the usual X terminology.
1237
02b14400 1238+++
a933dad1
DL
1239** New function `propertize'
1240
1241The new function `propertize' can be used to conveniently construct
1242strings with text properties.
1243
1244- Function: propertize STRING &rest PROPERTIES
1245
1246Value is a copy of STRING with text properties assigned as specified
1247by PROPERTIES. PROPERTIES is a sequence of pairs PROPERTY VALUE, with
1248PROPERTY being the name of a text property and VALUE being the
1249specified value of that property. Example:
1250
1251 (propertize "foo" 'face 'bold 'read-only t)
1252
1253+++
1254** push and pop macros.
1255
02b14400
RS
1256Simple versions of the push and pop macros of Common Lisp
1257are now defined in Emacs Lisp. These macros allow only symbols
a933dad1
DL
1258as the place that holds the list to be changed.
1259
1260(push NEWELT LISTNAME) add NEWELT to the front of LISTNAME's value.
1261(pop LISTNAME) return first elt of LISTNAME, and remove it
1262 (thus altering the value of LISTNAME).
1263
02b14400
RS
1264** New dolist and dotimes macros.
1265
6c7fd5aa
RS
1266Simple versions of the dolist and dotimes macros of Common Lisp
1267are now defined in Emacs Lisp.
02b14400
RS
1268
1269(dolist (VAR LIST [RESULT]) BODY...)
1270 Execute body once for each element of LIST,
1271 using the variable VAR to hold the current element.
1272 Then return the value of RESULT, or nil if RESULT is omitted.
1273
1274(dotimes (VAR COUNT [RESULT]) BODY...)
1275 Execute BODY with VAR bound to successive integers running from 0,
1276 inclusive, to COUNT, exclusive.
1277 Then return the value of RESULT, or nil if RESULT is omitted.
1278
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1279+++
1280** Regular expressions now support Posix character classes such
1281as [:alpha:], [:space:] and so on.
1282
1283[:digit:] matches 0 through 9
1284[:cntrl:] matches ASCII control characters
1285[:xdigit:] matches 0 through 9, a through f and A through F.
1286[:blank:] matches space and tab only
1287[:graph:] matches graphic characters--everything except ASCII control chars,
1288 space, and DEL.
1289[:print:] matches printing characters--everything except ASCII control chars
1290 and DEL.
1291[:alnum:] matches letters and digits.
1292 (But at present, for multibyte characters,
1293 it matches anything that has word syntax.)
1294[:alpha:] matches letters.
1295 (But at present, for multibyte characters,
1296 it matches anything that has word syntax.)
1297[:ascii:] matches ASCII (unibyte) characters.
1298[:nonascii:] matches non-ASCII (multibyte) characters.
1299[:lower:] matches anything lower-case.
1300[:punct:] matches punctuation.
1301 (But at present, for multibyte characters,
1302 it matches anything that has non-word syntax.)
1303[:space:] matches anything that has whitespace syntax.
1304[:upper:] matches anything upper-case.
1305[:word:] matches anything that has word syntax.
1306
1307+++
1308** Emacs now has built-in hash tables.
1309
1310The following functions are defined for hash tables:
1311
1312- Function: make-hash-table ARGS
1313
1314The argument list ARGS consists of keyword/argument pairs. All arguments
1315are optional. The following arguments are defined:
1316
1317:test TEST
1318
1319TEST must be a symbol specifying how to compare keys. Default is `eql'.
1320Predefined are `eq', `eql' and `equal'. If TEST is not predefined,
1321it must have been defined with `define-hash-table-test'.
1322
1323:size SIZE
1324
1325SIZE must be an integer > 0 giving a hint to the implementation how
1326many elements will be put in the hash table. Default size is 65.
1327
1328:rehash-size REHASH-SIZE
1329
1330REHASH-SIZE specifies by how much to grow a hash table once it becomes
1331full. If REHASH-SIZE is an integer, add that to the hash table's old
1332size to get the new size. Otherwise, REHASH-SIZE must be a float >
13331.0, and the new size is computed by multiplying REHASH-SIZE with the
1334old size. Default rehash size is 1.5.
1335
1336:rehash-threshold THRESHOLD
1337
1338THRESHOLD must be a float > 0 and <= 1.0 specifying when to resize the
1339hash table. It is resized when the ratio of (number of entries) /
1340(size of hash table) is >= THRESHOLD. Default threshold is 0.8.
1341
1342:weakness WEAK
1343
1344WEAK must be either nil, one of the symbols `key, `value', or t.
1345Entries are removed from weak tables during garbage collection if
1346their key and/or value are not referenced elsewhere outside of the
1347hash table. Default are non-weak hash tables.
1348
1349- Function: makehash &optional TEST
1350
1351Similar to make-hash-table, but only TEST can be specified.
1352
1353- Function: hash-table-p TABLE
1354
1355Returns non-nil if TABLE is a hash table object.
1356
1357- Function: copy-hash-table TABLE
1358
1359Returns a copy of TABLE. Only the table itself is copied, keys and
1360values are shared.
1361
1362- Function: hash-table-count TABLE
1363
1364Returns the number of entries in TABLE.
1365
1366- Function: hash-table-rehash-size TABLE
1367
1368Returns the rehash size of TABLE.
1369
1370- Function: hash-table-rehash-threshold TABLE
1371
1372Returns the rehash threshold of TABLE.
1373
1374- Function: hash-table-rehash-size TABLE
1375
1376Returns the size of TABLE.
1377
1378- Function: hash-table-rehash-test TABLE
1379
1380Returns the test TABLE uses to compare keys.
1381
1382- Function: hash-table-weakness TABLE
1383
1384Returns the weakness specified for TABLE.
1385
1386- Function: clrhash TABLE
1387
1388Clear TABLE.
1389
1390- Function: gethash KEY TABLE &optional DEFAULT
1391
1392Look up KEY in TABLE and return its associated VALUE or DEFAULT if
1393not found.
1394
79214ddf 1395- Function: puthash KEY VALUE TABLE
a933dad1
DL
1396
1397Associate KEY with VALUE in TABLE. If KEY is already associated with
1398another value, replace the old value with VALUE.
1399
1400- Function: remhash KEY TABLE
1401
1402Remove KEY from TABLE if it is there.
1403
1404- Function: maphash FUNCTION TABLE
1405
1406Call FUNCTION for all elements in TABLE. FUNCTION must take two
1407arguments KEY and VALUE.
1408
1409- Function: sxhash OBJ
1410
1411Return a hash code for Lisp object OBJ.
1412
1413- Function: define-hash-table-test NAME TEST-FN HASH-FN
1414
1415Define a new hash table test named NAME. If NAME is specified as
1416a test in `make-hash-table', the table created will use TEST-FN for
79214ddf 1417comparing keys, and HASH-FN to compute hash codes for keys. Test
a933dad1
DL
1418and hash function are stored as symbol property `hash-table-test'
1419of NAME with a value of (TEST-FN HASH-FN).
1420
1421TEST-FN must take two arguments and return non-nil if they are the same.
1422
1423HASH-FN must take one argument and return an integer that is the hash
1424code of the argument. The function should use the whole range of
1425integer values for hash code computation, including negative integers.
1426
1427Example: The following creates a hash table whose keys are supposed to
1428be strings that are compared case-insensitively.
1429
1430 (defun case-fold-string= (a b)
1431 (compare-strings a nil nil b nil nil t))
1432
1433 (defun case-fold-string-hash (a)
1434 (sxhash (upcase a)))
1435
79214ddf 1436 (define-hash-table-test 'case-fold 'case-fold-string=
a933dad1
DL
1437 'case-fold-string-hash))
1438
1439 (make-hash-table :test 'case-fold)
1440
1441+++
1442** The Lisp reader handles circular structure.
1443
1444It now works to use the #N= and #N# constructs to represent
1445circular structures. For example, #1=(a . #1#) represents
1446a cons cell which is its own cdr.
1447
1448+++
1449** The Lisp printer handles circular structure.
1450
1451If you bind print-circle to a non-nil value, the Lisp printer outputs
1452#N= and #N# constructs to represent circular and shared structure.
1453
a933dad1
DL
1454+++
1455** If the second argument to `move-to-column' is anything but nil or
1456t, that means replace a tab with spaces if necessary to reach the
1457specified column, but do not add spaces at the end of the line if it
1458is too short to reach that column.
1459
1460+++
1461** perform-replace has a new feature: the REPLACEMENTS argument may
1462now be a cons cell (FUNCTION . DATA). This means to call FUNCTION
1463after each match to get the replacement text. FUNCTION is called with
1464two arguments: DATA, and the number of replacements already made.
1465
1466If the FROM-STRING contains any upper-case letters,
1467perform-replace also turns off `case-fold-search' temporarily
1468and inserts the replacement text without altering case in it.
1469
1470+++
1471** The function buffer-size now accepts an optional argument
1472to specify which buffer to return the size of.
1473
1474+++
1475** The calendar motion commands now run the normal hook
1476calendar-move-hook after moving point.
1477
1478+++
1479** The new variable small-temporary-file-directory specifies a
1480directory to use for creating temporary files that are likely to be
1481small. (Certain Emacs features use this directory.) If
1482small-temporary-file-directory is nil, they use
1483temporary-file-directory instead.
1484
1485+++
1486** The variable `inhibit-modification-hooks', if non-nil, inhibits all
1487the hooks that track changes in the buffer. This affects
1488`before-change-functions' and `after-change-functions', as well as
1489hooks attached to text properties and overlay properties.
1490
1491+++
1492** assoc-delete-all is a new function that deletes all the
1493elements of an alist which have a particular value as the car.
1494
1495+++
1496** make-temp-file provides a more reliable way to create a temporary file.
1497
1498make-temp-file is used like make-temp-name, except that it actually
1499creates the file before it returns. This prevents a timing error,
1500ensuring that no other job can use the same name for a temporary file.
1501
1502+++
1503** New exclusive-open feature in `write-region'
1504
1505The optional seventh arg is now called MUSTBENEW. If non-nil, it insists
1506on a check for an existing file with the same name. If MUSTBENEW
1507is `excl', that means to get an error if the file already exists;
1508never overwrite. If MUSTBENEW is neither nil nor `excl', that means
1509ask for confirmation before overwriting, but do go ahead and
1510overwrite the file if the user gives confirmation.
1511
1512If the MUSTBENEW argument in `write-region' is `excl',
1513that means to use a special feature in the `open' system call
1514to get an error if the file exists at that time.
1515The error reported is `file-already-exists'.
1516
1517+++
1518** Function `format' now handles text properties.
1519
1520Text properties of the format string are applied to the result string.
1521If the result string is longer than the format string, text properties
1522ending at the end of the format string are extended to the end of the
1523result string.
1524
1525Text properties from string arguments are applied to the result
1526string where arguments appear in the result string.
1527
1528Example:
1529
1530 (let ((s1 "hello, %s")
1531 (s2 "world"))
1532 (put-text-property 0 (length s1) 'face 'bold s1)
1533 (put-text-property 0 (length s2) 'face 'italic s2)
b246b1f6 1534 (format s1 s2))
a933dad1
DL
1535
1536results in a bold-face string with an italic `world' at the end.
1537
1538+++
1539** Messages can now be displayed with text properties.
1540
1541Text properties are handled as described above for function `format'.
1542The following example displays a bold-face message with an italic
1543argument in it.
1544
1545 (let ((msg "hello, %s!")
1546 (arg "world"))
1547 (put-text-property 0 (length msg) 'face 'bold msg)
1548 (put-text-property 0 (length arg) 'face 'italic arg)
1549 (message msg arg))
1550
1551+++
1552** Sound support
1553
1554Emacs supports playing sound files on GNU/Linux and the free BSDs
1555(Voxware driver and native BSD driver, aka as Luigi's driver).
1556
1557Currently supported file formats are RIFF-WAVE (*.wav) and Sun Audio
1558(*.au). You must configure Emacs with the option `--with-sound=yes'
1559to enable sound support.
1560
1561Sound files can be played by calling (play-sound SOUND). SOUND is a
1562list of the form `(sound PROPERTY...)'. The function is only defined
1563when sound support is present for the system on which Emacs runs. The
1564functions runs `play-sound-functions' with one argument which is the
1565sound to play, before playing the sound.
1566
1567The following sound properties are supported:
1568
1569- `:file FILE'
1570
1571FILE is a file name. If FILE isn't an absolute name, it will be
1572searched relative to `data-directory'.
1573
6fb40beb
GM
1574- `:data DATA'
1575
1576DATA is a string containing sound data. Either :file or :data
1577may be present, but not both.
1578
a933dad1
DL
1579- `:volume VOLUME'
1580
1581VOLUME must be an integer in the range 0..100 or a float in the range
15820..1. This property is optional.
1583
1584Other properties are ignored.
1585
1586** `multimedia' is a new Finder keyword and Custom group.
356673d4
DL
1587
1588** keywordp is a new predicate to test efficiently for an object being
1589a keyword symbol.
fc91dc2d
GM
1590
1591** Changes to garbage collection
1592
1593*** The function garbage-collect now additionally returns the number
1594of live and free strings.
1595
1596*** There is a new variable `strings-consed' holding the number of
1597strings that have been consed so far.
1598
a933dad1
DL
1599\f
1600* New Lisp-level Display features in Emacs 21.1
1601
1602Note that +++ before an item means the Lisp manual has been updated.
1603--- means that I have decided it does not need to be in the Lisp manual.
1604When you add a new item, please add it without either +++ or ---
1605so I will know I still need to look at it -- rms.
1606
1607** New face implementation.
1608
1609Emacs faces have been reimplemented from scratch. They don't use XLFD
1610font names anymore and face merging now works as expected.
1611
1612+++
1613*** New faces.
1614
1615Each face can specify the following display attributes:
1616
1617 1. Font family or fontset alias name.
79214ddf 1618
a933dad1
DL
1619 2. Relative proportionate width, aka character set width or set
1620 width (swidth), e.g. `semi-compressed'.
79214ddf 1621
a933dad1 1622 3. Font height in 1/10pt
79214ddf 1623
a933dad1 1624 4. Font weight, e.g. `bold'.
79214ddf 1625
a933dad1 1626 5. Font slant, e.g. `italic'.
79214ddf 1627
a933dad1 1628 6. Foreground color.
79214ddf 1629
a933dad1
DL
1630 7. Background color.
1631
1632 8. Whether or not characters should be underlined, and in what color.
1633
1634 9. Whether or not characters should be displayed in inverse video.
1635
1636 10. A background stipple, a bitmap.
1637
1638 11. Whether or not characters should be overlined, and in what color.
1639
1640 12. Whether or not characters should be strike-through, and in what
1641 color.
1642
1643 13. Whether or not a box should be drawn around characters, its
1644 color, the width of the box lines, and 3D appearance.
1645
1646Faces are frame-local by nature because Emacs allows to define the
1647same named face (face names are symbols) differently for different
1648frames. Each frame has an alist of face definitions for all named
1649faces. The value of a named face in such an alist is a Lisp vector
1650with the symbol `face' in slot 0, and a slot for each each of the face
1651attributes mentioned above.
1652
1653There is also a global face alist `face-new-frame-defaults'. Face
1654definitions from this list are used to initialize faces of newly
1655created frames.
79214ddf 1656
a933dad1
DL
1657A face doesn't have to specify all attributes. Those not specified
1658have a nil value. Faces specifying all attributes are called
1659`fully-specified'.
1660
1661+++
1662*** Face merging.
1663
1664The display style of a given character in the text is determined by
1665combining several faces. This process is called `face merging'. Any
1666aspect of the display style that isn't specified by overlays or text
1667properties is taken from the `default' face. Since it is made sure
1668that the default face is always fully-specified, face merging always
1669results in a fully-specified face.
1670
1671+++
1672*** Face realization.
1673
1674After all face attributes for a character have been determined by
1675merging faces of that character, that face is `realized'. The
1676realization process maps face attributes to what is physically
1677available on the system where Emacs runs. The result is a `realized
1678face' in form of an internal structure which is stored in the face
1679cache of the frame on which it was realized.
1680
1681Face realization is done in the context of the charset of the
1682character to display because different fonts and encodings are used
1683for different charsets. In other words, for characters of different
1684charsets, different realized faces are needed to display them.
1685
1686Except for composite characters, faces are always realized for a
1687specific character set and contain a specific font, even if the face
1688being realized specifies a fontset. The reason is that the result of
1689the new font selection stage is better than what can be done with
1690statically defined font name patterns in fontsets.
1691
1692In unibyte text, Emacs' charsets aren't applicable; function
1693`char-charset' reports ASCII for all characters, including those >
16940x7f. The X registry and encoding of fonts to use is determined from
1695the variable `face-default-registry' in this case. The variable is
1696initialized at Emacs startup time from the font the user specified for
1697Emacs.
1698
1699Currently all unibyte text, i.e. all buffers with
1700`enable-multibyte-characters' nil are displayed with fonts of the same
1701registry and encoding `face-default-registry'. This is consistent
1702with the fact that languages can also be set globally, only.
1703
1704++++
1705**** Clearing face caches.
1706
1707The Lisp function `clear-face-cache' can be called to clear face caches
1708on all frames. If called with a non-nil argument, it will also unload
1709unused fonts.
1710
1711+++
1712*** Font selection.
79214ddf 1713
a933dad1
DL
1714Font selection tries to find the best available matching font for a
1715given (charset, face) combination. This is done slightly differently
1716for faces specifying a fontset, or a font family name.
1717
1718If the face specifies a fontset name, that fontset determines a
1719pattern for fonts of the given charset. If the face specifies a font
1720family, a font pattern is constructed. Charset symbols have a
1721property `x-charset-registry' for that purpose that maps a charset to
1722an XLFD registry and encoding in the font pattern constructed.
1723
1724Available fonts on the system on which Emacs runs are then matched
1725against the font pattern. The result of font selection is the best
1726match for the given face attributes in this font list.
1727
1728Font selection can be influenced by the user.
1729
1730The user can specify the relative importance he gives the face
1731attributes width, height, weight, and slant by setting
1732face-font-selection-order (faces.el) to a list of face attribute
1733names. The default is (:width :height :weight :slant), and means
1734that font selection first tries to find a good match for the font
1735width specified by a face, then---within fonts with that width---tries
1736to find a best match for the specified font height, etc.
1737
1738Setting `face-alternative-font-family-alist' allows the user to
1739specify alternative font families to try if a family specified by a
1740face doesn't exist.
1741
1742+++
1743**** Scalable fonts
1744
1745Emacs can make use of scalable fonts but doesn't do so by default,
1746since the use of too many or too big scalable fonts may crash XFree86
1747servers.
1748
1749To enable scalable font use, set the variable
b246b1f6 1750`scalable-fonts-allowed'. A value of nil, the default, means never use
a933dad1
DL
1751scalable fonts. A value of t means any scalable font may be used.
1752Otherwise, the value must be a list of regular expressions. A
1753scalable font may then be used if it matches a regular expression from
1754that list. Example:
1755
1756 (setq scalable-fonts-allowed '("muleindian-2$"))
1757
1758allows the use of scalable fonts with registry `muleindian-2'.
1759
1760+++
1761*** Functions and variables related to font selection.
1762
1763- Function: x-family-fonts &optional FAMILY FRAME
1764
1765Return a list of available fonts of family FAMILY on FRAME. If FAMILY
1766is omitted or nil, list all families. Otherwise, FAMILY must be a
1767string, possibly containing wildcards `?' and `*'.
1768
1769If FRAME is omitted or nil, use the selected frame. Each element of
1770the result is a vector [FAMILY WIDTH POINT-SIZE WEIGHT SLANT FIXED-P
1771FULL REGISTRY-AND-ENCODING]. FAMILY is the font family name.
1772POINT-SIZE is the size of the font in 1/10 pt. WIDTH, WEIGHT, and
1773SLANT are symbols describing the width, weight and slant of the font.
1774These symbols are the same as for face attributes. FIXED-P is non-nil
1775if the font is fixed-pitch. FULL is the full name of the font, and
1776REGISTRY-AND-ENCODING is a string giving the registry and encoding of
1777the font. The result list is sorted according to the current setting
1778of the face font sort order.
1779
79214ddf 1780- Function: x-font-family-list
a933dad1
DL
1781
1782Return a list of available font families on FRAME. If FRAME is
1783omitted or nil, use the selected frame. Value is a list of conses
1784(FAMILY . FIXED-P) where FAMILY is a font family, and FIXED-P is
1785non-nil if fonts of that family are fixed-pitch.
1786
1787- Variable: font-list-limit
1788
1789Limit for font matching. If an integer > 0, font matching functions
1790won't load more than that number of fonts when searching for a
1791matching font. The default is currently 100.
1792
1793+++
1794*** Setting face attributes.
1795
1796For the most part, the new face implementation is interface-compatible
1797with the old one. Old face attribute related functions are now
1798implemented in terms of the new functions `set-face-attribute' and
1799`face-attribute'.
1800
1801Face attributes are identified by their names which are keyword
1802symbols. All attributes can be set to `unspecified'.
1803
1804The following attributes are recognized:
1805
1806`:family'
1807
1808VALUE must be a string specifying the font family, e.g. ``courier'',
1809or a fontset alias name. If a font family is specified, wild-cards `*'
1810and `?' are allowed.
1811
1812`:width'
1813
1814VALUE specifies the relative proportionate width of the font to use.
1815It must be one of the symbols `ultra-condensed', `extra-condensed',
1816`condensed', `semi-condensed', `normal', `semi-expanded', `expanded',
1817`extra-expanded', or `ultra-expanded'.
1818
1819`:height'
1820
1821VALUE must be an integer specifying the height of the font to use in
18221/10 pt.
1823
1824`:weight'
1825
1826VALUE specifies the weight of the font to use. It must be one of the
1827symbols `ultra-bold', `extra-bold', `bold', `semi-bold', `normal',
1828`semi-light', `light', `extra-light', `ultra-light'.
1829
1830`:slant'
1831
1832VALUE specifies the slant of the font to use. It must be one of the
1833symbols `italic', `oblique', `normal', `reverse-italic', or
1834`reverse-oblique'.
1835
1836`:foreground', `:background'
1837
1838VALUE must be a color name, a string.
1839
1840`:underline'
1841
1842VALUE specifies whether characters in FACE should be underlined. If
1843VALUE is t, underline with foreground color of the face. If VALUE is
1844a string, underline with that color. If VALUE is nil, explicitly
1845don't underline.
1846
1847`:overline'
1848
1849VALUE specifies whether characters in FACE should be overlined. If
1850VALUE is t, overline with foreground color of the face. If VALUE is a
1851string, overline with that color. If VALUE is nil, explicitly don't
1852overline.
1853
1854`:strike-through'
1855
1856VALUE specifies whether characters in FACE should be drawn with a line
1857striking through them. If VALUE is t, use the foreground color of the
1858face. If VALUE is a string, strike-through with that color. If VALUE
1859is nil, explicitly don't strike through.
1860
1861`:box'
1862
1863VALUE specifies whether characters in FACE should have a box drawn
1864around them. If VALUE is nil, explicitly don't draw boxes. If
1865VALUE is t, draw a box with lines of width 1 in the foreground color
1866of the face. If VALUE is a string, the string must be a color name,
1867and the box is drawn in that color with a line width of 1. Otherwise,
1868VALUE must be a property list of the form `(:line-width WIDTH
1869:color COLOR :style STYLE)'. If a keyword/value pair is missing from
1870the property list, a default value will be used for the value, as
1871specified below. WIDTH specifies the width of the lines to draw; it
1872defaults to 1. COLOR is the name of the color to draw in, default is
1873the foreground color of the face for simple boxes, and the background
1874color of the face for 3D boxes. STYLE specifies whether a 3D box
1875should be draw. If STYLE is `released-button', draw a box looking
1876like a released 3D button. If STYLE is `pressed-button' draw a box
1877that appears like a pressed button. If STYLE is nil, the default if
1878the property list doesn't contain a style specification, draw a 2D
1879box.
1880
1881`:inverse-video'
1882
1883VALUE specifies whether characters in FACE should be displayed in
1884inverse video. VALUE must be one of t or nil.
1885
1886`:stipple'
1887
1888If VALUE is a string, it must be the name of a file of pixmap data.
1889The directories listed in the `x-bitmap-file-path' variable are
1890searched. Alternatively, VALUE may be a list of the form (WIDTH
1891HEIGHT DATA) where WIDTH and HEIGHT are the size in pixels, and DATA
1892is a string containing the raw bits of the bitmap. VALUE nil means
1893explicitly don't use a stipple pattern.
1894
1895For convenience, attributes `:family', `:width', `:height', `:weight',
1896and `:slant' may also be set in one step from an X font name:
1897
1898`:font'
1899
1900Set font-related face attributes from VALUE. VALUE must be a valid
1901XLFD font name. If it is a font name pattern, the first matching font
1902is used--this is for compatibility with the behavior of previous
1903versions of Emacs.
1904
1905For compatibility with Emacs 20, keywords `:bold' and `:italic' can
1906be used to specify that a bold or italic font should be used. VALUE
1907must be t or nil in that case. A value of `unspecified' is not allowed."
1908
1909Please see also the documentation of `set-face-attribute' and
1910`defface'.
1911
1912*** Face attributes and X resources
1913
1914The following X resource names can be used to set face attributes
1915from X resources:
1916
1917 Face attribute X resource class
1918-----------------------------------------------------------------------
1919 :family attributeFamily . Face.AttributeFamily
1920 :width attributeWidth Face.AttributeWidth
1921 :height attributeHeight Face.AttributeHeight
1922 :weight attributeWeight Face.AttributeWeight
1923 :slant attributeSlant Face.AttributeSlant
1924 foreground attributeForeground Face.AttributeForeground
1925 :background attributeBackground . Face.AttributeBackground
1926 :overline attributeOverline Face.AttributeOverline
1927 :strike-through attributeStrikeThrough Face.AttributeStrikeThrough
1928 :box attributeBox Face.AttributeBox
1929 :underline attributeUnderline Face.AttributeUnderline
1930 :inverse-video attributeInverse Face.AttributeInverse
1931 :stipple attributeStipple Face.AttributeStipple
79214ddf 1932 or attributeBackgroundPixmap
a933dad1
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1933 Face.AttributeBackgroundPixmap
1934 :font attributeFont Face.AttributeFont
1935 :bold attributeBold Face.AttributeBold
1936 :italic attributeItalic . Face.AttributeItalic
1937 :font attributeFont Face.AttributeFont
1938
1939+++
1940*** Text property `face'.
1941
1942The value of the `face' text property can now be a single face
1943specification or a list of such specifications. Each face
1944specification can be
1945
19461. A symbol or string naming a Lisp face.
1947
19482. A property list of the form (KEYWORD VALUE ...) where each
1949 KEYWORD is a face attribute name, and VALUE is an appropriate value
1950 for that attribute. Please see the doc string of `set-face-attribute'
1951 for face attribute names.
1952
19533. Conses of the form (FOREGROUND-COLOR . COLOR) or
1954 (BACKGROUND-COLOR . COLOR) where COLOR is a color name. This is
1955 for compatibility with previous Emacs versions.
1956
1957+++
1958** Support functions for colors on text-only terminals.
1959
acf3ecb7
EZ
1960The function `tty-color-define' can be used to define colors for use
1961on TTY and MSDOS frames. It maps a color name to a color number on
1962the terminal. Emacs defines a couple of common color mappings by
a933dad1 1963default. You can get defined colors with a call to
acf3ecb7 1964`defined-colors'. The function `tty-color-clear' can be
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DL
1965used to clear the mapping table.
1966
acf3ecb7
EZ
1967** Unified support for colors independent of frame type.
1968
1969The new functions `defined-colors', `color-defined-p', `color-values',
1970and `display-color-p' work for any type of frame. On frames whose
1971type is neither x nor w32, these functions transparently map X-style
1972color specifications to the closest colors supported by the frame
1973display. Lisp programs should use these new functions instead of the
1974old `x-defined-colors', `x-color-defined-p', `x-color-values', and
1975`x-display-color-p'. (The old function names are still available for
1976compatibility; they are now aliases of the new names.) Lisp programs
1977should no more look at the value of the variable window-system to
1978modify their color-related behavior.
1979
1980The primitives `color-gray-p' and `color-supported-p' also work for
1981any frame type.
1982
8a5719f0
EZ
1983** Platform-independent functions to describe display capabilities.
1984
1985The new functions `display-mouse-p', `display-popup-menus-p',
1986`display-graphic-p', `display-selections-p', `display-screens',
1987`display-pixel-width', `display-pixel-height', `display-mm-width',
1988`display-mm-height', `display-backing-store', `display-save-under',
1989`display-planes', `display-color-cells', `display-visual-class', and
1990`display-grayscale-p' describe the basic capabilities of a particular
1991display. Lisp programs should call these functions instead of testing
1992the value of the variables `window-system' or `system-type', or calling
1993platform-specific functions such as `x-display-pixel-width'.
1994
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1995+++
1996** The minibuffer prompt is now actually inserted in the minibuffer.
a933dad1 1997
463cac2d 1998This makes it possible to scroll through the prompt, if you want to.
a933dad1
DL
1999
2000The function minubuffer-prompt-end returns the current position of the
2001end of the minibuffer prompt, if the minibuffer is current.
2002Otherwise, it returns zero.
2003
463cac2d
GM
2004** New `field' abstraction in buffers.
2005
2006There is now code to support an abstraction called `fields' in emacs
2007buffers. A field is a contiguous region of text with the same `field'
2008text-property.
2009
9a9dfda8 2010Many emacs functions, such as forward-word, forward-sentence,
463cac2d 2011forward-paragraph, beginning-of-line, etc., stop moving when they come
9a9dfda8 2012to the boundary between fields; beginning-of-line and end-of-line will
463cac2d 2013not let the point move past the field boundary, but other movement
fc7ac24f
GM
2014commands continue into the next field if repeated. Stopping at field
2015boundaries can be suppressed programmatically by binding
2016`inhibit-field-text-motion' to a non-nil value around calls to these
2017functions.
463cac2d
GM
2018
2019Now that the minibuffer prompt is inserted into the minibuffer, it is in
9a9dfda8 2020a separate field from the user-input part of the buffer, so that common
463cac2d 2021editing commands treat the user's text separately from the prompt.
a933dad1 2022
9a9dfda8
GM
2023The following functions are defined for operating on fields:
2024
2025- Function: constrain-to-field NEW-POS OLD-POS &optional ESCAPE-FROM-EDGE ONLY-IN-LINE
2026
2027Return the position closest to NEW-POS that is in the same field as OLD-POS.
2028A field is a region of text with the same `field' property.
2029If NEW-POS is nil, then the current point is used instead, and set to the
2030constrained position if that is is different.
2031
2032If OLD-POS is at the boundary of two fields, then the allowable
2033positions for NEW-POS depends on the value of the optional argument
2034ESCAPE-FROM-EDGE: If ESCAPE-FROM-EDGE is nil, then NEW-POS is
2035constrained to the field that has the same `field' text-property
2036as any new characters inserted at OLD-POS, whereas if ESCAPE-FROM-EDGE
2037is non-nil, NEW-POS is constrained to the union of the two adjacent
2038fields.
2039
2040If the optional argument ONLY-IN-LINE is non-nil and constraining
2041NEW-POS would move it to a different line, NEW-POS is returned
2042unconstrained. This useful for commands that move by line, like
2043C-n or C-a, which should generally respect field boundaries
2044only in the case where they can still move to the right line.
2045
2046- Function: erase-field &optional POS
2047
2048Erases the field surrounding POS.
2049A field is a region of text with the same `field' property.
2050If POS is nil, the position of the current buffer's point is used.
2051
2052- Function: field-beginning &optional POS ESCAPE-FROM-EDGE
2053
2054Return the beginning of the field surrounding POS.
2055A field is a region of text with the same `field' property.
2056If POS is nil, the position of the current buffer's point is used.
2057If ESCAPE-FROM-EDGE is non-nil and POS is already at beginning of an
2058field, then the beginning of the *previous* field is returned.
2059
2060- Function: field-end &optional POS ESCAPE-FROM-EDGE
2061
2062Return the end of the field surrounding POS.
2063A field is a region of text with the same `field' property.
2064If POS is nil, the position of the current buffer's point is used.
2065If ESCAPE-FROM-EDGE is non-nil and POS is already at end of a field,
2066then the end of the *following* field is returned.
2067
2068- Function: field-string &optional POS
2069
2070Return the contents of the field surrounding POS as a string.
2071A field is a region of text with the same `field' property.
2072If POS is nil, the position of the current buffer's point is used.
2073
2074- Function: field-string-no-properties &optional POS
2075
2076Return the contents of the field around POS, without text-properties.
2077A field is a region of text with the same `field' property.
2078If POS is nil, the position of the current buffer's point is used.
2079
a933dad1
DL
2080+++
2081** Image support.
2082
2083Emacs can now display images. Images are inserted into text by giving
2084strings or buffer text a `display' text property containing one of
2085(AREA IMAGE) or IMAGE. The display of the `display' property value
2086replaces the display of the characters having that property.
2087
2088If the property value has the form (AREA IMAGE), AREA must be one of
2089`(margin left-margin)', `(margin right-margin)' or `(margin nil)'. If
2090AREA is `(margin nil)', IMAGE will be displayed in the text area of a
2091window, otherwise it will be displayed in the left or right marginal
2092area.
2093
2094IMAGE is an image specification.
2095
2096*** Image specifications
2097
2098Image specifications are lists of the form `(image PROPS)' where PROPS
2099is a property list whose keys are keyword symbols. Each
2100specifications must contain a property `:type TYPE' with TYPE being a
35a5514b
GM
2101symbol specifying the image type, e.g. `xbm'. Properties not
2102described below are ignored.
a933dad1
DL
2103
2104The following is a list of properties all image types share.
2105
2106`:ascent ASCENT'
2107
2108ASCENT must be a number in the range 0..100, and specifies the percentage
2109of the image's height to use for its ascent. Default is 50.
2110
2111`:margin MARGIN'
2112
79214ddf 2113MARGIN must be a number >= 0 specifying how many pixels to put as
a933dad1
DL
2114margin around the image. Default is 0.
2115
2116`:relief RELIEF'
2117
2118RELIEF is analogous to the `:relief' attribute of faces. Puts a relief
2119around an image.
2120
2121`:algorithm ALGO'
2122
2123Apply an image algorithm to the image before displaying it. ALGO must
2124be a symbol specifying the algorithm. Currently only `laplace' is
2125supported which applies a Laplace edge detection algorithm to an image
2126which is intended to display images "disabled."
2127
2128`:heuristic-mask BG'
2129
2130If BG is not nil, build a clipping mask for the image, so that the
2131background of a frame is visible behind the image. If BG is t,
2132determine the background color of the image by looking at the 4
2133corners of the image, assuming the most frequently occuring color from
2134the corners is the background color of the image. Otherwise, BG must
2135be a list `(RED GREEN BLUE)' specifying the color to assume for the
2136background of the image.
2137
2138`:file FILE'
2139
2140Load image from FILE. If FILE is not absolute after expanding it,
2141search for the image in `data-directory'. Some image types support
2142building images from data. When this is done, no `:file' property
2143may be present in the image specification.
2144
518df5c4
GM
2145`:data DATA'
2146
2147Get image data from DATA. (As of this writing, this is not yet
2148supported for image type `postscript'). Either :file or :data may be
2149present in an image specification, but not both. All image types
2150support strings as DATA, some types allow additional types of DATA.
2151
a933dad1
DL
2152*** Supported image types
2153
b246b1f6 2154**** XBM, image type `xbm'.
a933dad1
DL
2155
2156XBM images don't require an external library. Additional image
2157properties supported are
2158
2159`:foreground FG'
2160
2161FG must be a string specifying the image foreground color. Default
2162is the frame's foreground.
2163
2164`:background FG'
2165
2166BG must be a string specifying the image foreground color. Default is
2167the frame's background color.
2168
2169XBM images can be constructed from data instead of file. In this
2170case, the image specification must contain the following properties
2171instead of a `:file' property.
2172
2173`:width WIDTH'
2174
2175WIDTH specifies the width of the image in pixels.
2176
2177`:height HEIGHT'
2178
2179HEIGHT specifies the height of the image in pixels.
2180
2181`:data DATA'
2182
2183DATA must be either
2184
2185 1. a string large enough to hold the bitmap data, i.e. it must
2186 have a size >= (WIDTH + 7) / 8 * HEIGHT
2187
2188 2. a bool-vector of size >= WIDTH * HEIGHT
2189
2190 3. a vector of strings or bool-vectors, one for each line of the
2191 bitmap.
2192
2193**** XPM, image type `xpm'
2194
2195XPM images require the external library `libXpm', package
2196`xpm-3.4k.tar.gz', version 3.4k or later. Make sure the library is
2197found when Emacs is configured by supplying appropriate paths via
2198`--x-includes' and `--x-libraries'.
2199
2200Additional image properties supported are:
2201
2202`:color-symbols SYMBOLS'
2203
2204SYMBOLS must be a list of pairs (NAME . COLOR), with NAME being the
2205name of color as it appears in an XPM file, and COLOR being an X color
2206name.
2207
2208XPM images can be built from memory instead of files. In that case,
2209add a `:data' property instead of a `:file' property.
2210
a933dad1
DL
2211The XPM library uses libz in its implementation so that it is able
2212to display compressed images.
2213
2214**** PBM, image type `pbm'
2215
2216PBM images don't require an external library. Color, gray-scale and
2217mono images are supported. There are no additional image properties
2218defined.
2219
2220**** JPEG, image type `jpeg'
2221
2222Support for JPEG images requires the external library `libjpeg',
3bd37feb
GM
2223package `jpegsrc.v6a.tar.gz', or later. Additional image properties
2224are:
2225
a933dad1
DL
2226**** TIFF, image type `tiff'
2227
2228Support for TIFF images requires the external library `libtiff',
2229package `tiff-v3.4-tar.gz', or later. There are no additional image
2230properties defined.
2231
2232**** GIF, image type `gif'
2233
2234Support for GIF images requires the external library `libungif', package
2235`libungif-4.1.0', or later.
2236
2237Additional image properties supported are:
2238
2239`:index INDEX'
2240
2241INDEX must be an integer >= 0. Load image number INDEX from a
2242multi-image GIF file. An error is signalled if INDEX is too large.
2243
2244This could be used to implement limited support for animated GIFs.
2245For example, the following function displays a multi-image GIF file
2246at point-min in the current buffer, switching between sub-images
2247every 0.1 seconds.
2248
2249(defun show-anim (file max)
2250 "Display multi-image GIF file FILE which contains MAX subimages."
2251 (display-anim (current-buffer) file 0 max t))
2252
2253(defun display-anim (buffer file idx max first-time)
2254 (when (= idx max)
2255 (setq idx 0))
518df5c4 2256 (let ((img (create-image file nil nil :index idx)))
a933dad1
DL
2257 (save-excursion
2258 (set-buffer buffer)
2259 (goto-char (point-min))
2260 (unless first-time (delete-char 1))
2261 (insert-image img "x"))
2262 (run-with-timer 0.1 nil 'display-anim buffer file (1+ idx) max nil)))
2263
2264**** PNG, image type `png'
2265
2266Support for PNG images requires the external library `libpng',
2267package `libpng-1.0.2.tar.gz', or later. There are no additional image
2268properties defined.
2269
2270**** Ghostscript, image type `postscript'.
2271
2272Additional image properties supported are:
2273
2274`:pt-width WIDTH'
2275
2276WIDTH is width of the image in pt (1/72 inch). WIDTH must be an
b246b1f6 2277integer. This is a required property.
a933dad1
DL
2278
2279`:pt-height HEIGHT'
2280
2281HEIGHT specifies the height of the image in pt (1/72 inch). HEIGHT
b246b1f6 2282must be a integer. This is an required property.
a933dad1
DL
2283
2284`:bounding-box BOX'
2285
2286BOX must be a list or vector of 4 integers giving the bounding box of
2287the PS image, analogous to the `BoundingBox' comment found in PS
2288files. This is an required property.
2289
2290Part of the Ghostscript interface is implemented in Lisp. See
2291lisp/gs.el.
2292
2293*** Lisp interface.
2294
79214ddf
FP
2295The variable `image-types' contains a list of those image types
2296which are supported in the current configuration.
a933dad1
DL
2297
2298Images are stored in an image cache and removed from the cache when
2299they haven't been displayed for `image-cache-eviction-delay seconds.
2300The function `clear-image-cache' can be used to clear the image cache
2301manually.
2302
2303*** Simplified image API, image.el
2304
2305The new Lisp package image.el contains functions that simplify image
2306creation and putting images into text. The function `create-image'
2307can be used to create images. The macro `defimage' can be used to
2308define an image based on available image types. The functions
2309`put-image' and `insert-image' can be used to insert an image into a
2310buffer.
2311
2312+++
2313** Display margins.
2314
2315Windows can now have margins which are used for special text
2316and images.
2317
2318To give a window margins, either set the buffer-local variables
2319`left-margin-width' and `right-margin-width', or call
2320`set-window-margins'. The function `window-margins' can be used to
2321obtain the current settings. To make `left-margin-width' and
2322`right-margin-width' take effect, you must set them before displaying
2323the buffer in a window, or use `set-window-buffer' to force an update
2324of the display margins.
2325
2326You can put text in margins by giving it a `display' text property
2327containing a pair of the form `(LOCATION . VALUE)', where LOCATION is
2328one of `left-margin' or `right-margin' or nil. VALUE can be either a
2329string, an image specification or a stretch specification (see later
2330in this file).
2331
2332+++
2333** Help display
2334
2335Emacs displays short help messages in the echo area, when the mouse
2336moves over a tool-bar item or a piece of text that has a text property
2337`help-echo'. This feature also applies to strings in the mode line
2338that have a `help-echo' property.
2339
2340The value of the `help-echo' property must be a string. For tool-bar
2341items, their key definition is used to determine the help to display.
2342If their definition contains a property `:help FORM', FORM is
2343evaluated to determine the help string. Otherwise, the caption of the
2344tool-bar item is used.
2345
2346The hook `show-help-function' can be set to a function that displays
2347help differently. For example, enabling a tooltip window causes the
2348help display to appear there instead of in the echo area.
2349
2350+++
2351** Vertical fractional scrolling.
2352
2353The display of text in windows can be scrolled smoothly in pixels.
2354This is useful, for example, for making parts of large images visible.
2355
2356The function `window-vscroll' returns the current value of vertical
2357scrolling, a non-negative fraction of the canonical character height.
2358The function `set-window-vscroll' can be used to set the vertical
2359scrolling value. Here is an example of how these function might be
2360used.
2361
79214ddf
FP
2362 (global-set-key [A-down]
2363 #'(lambda ()
a933dad1 2364 (interactive)
79214ddf 2365 (set-window-vscroll (selected-window)
a933dad1 2366 (+ 0.5 (window-vscroll)))))
79214ddf 2367 (global-set-key [A-up]
a933dad1
DL
2368 #'(lambda ()
2369 (interactive)
79214ddf 2370 (set-window-vscroll (selected-window)
a933dad1
DL
2371 (- (window-vscroll) 0.5)))))
2372
2373+++
2374** New hook `fontification-functions'.
2375
2376Functions from `fontification-functions' are called from redisplay
2377when it encounters a region of text that is not yet fontified. This
2378variable automatically becomes buffer-local when set. Each function
2379is called with one argument, POS.
2380
2381At least one of the hook functions should fontify one or more
2382characters starting at POS in the current buffer. It should mark them
2383as fontified by giving them a non-nil value of the `fontified' text
2384property. It may be reasonable for these functions to check for the
2385`fontified' property and not put it back on, but they do not have to.
2386
2387+++
2388** Tool bar support.
2389
2390Emacs supports a tool bar at the top of a frame under X. The frame
2391parameter `tool-bar-lines' (X resource "toolBar", class "ToolBar")
2392controls how may lines to reserve for the tool bar. A zero value
2393suppresses the tool bar. If the value is non-zero and
2394`auto-resize-tool-bars' is non-nil the tool bar's size will be changed
2395automatically so that all tool bar items are visible.
2396
2397*** Tool bar item definitions
2398
2399Tool bar items are defined using `define-key' with a prefix-key
2400`tool-bar'. For example `(define-key global-map [tool-bar item1] ITEM)'
2401where ITEM is a list `(menu-item CAPTION BINDING PROPS...)'.
79214ddf 2402
a933dad1
DL
2403CAPTION is the caption of the item, If it's not a string, it is
2404evaluated to get a string. The caption is currently not displayed in
2405the tool bar, but it is displayed if the item doesn't have a `:help'
2406property (see below).
79214ddf 2407
a933dad1
DL
2408BINDING is the tool bar item's binding. Tool bar items with keymaps as
2409binding are currently ignored.
2410
2411The following properties are recognized:
2412
2413`:enable FORM'.
79214ddf 2414
a933dad1
DL
2415FORM is evaluated and specifies whether the tool bar item is enabled
2416or disabled.
79214ddf 2417
a933dad1 2418`:visible FORM'
79214ddf 2419
a933dad1 2420FORM is evaluated and specifies whether the tool bar item is displayed.
79214ddf 2421
a933dad1
DL
2422`:filter FUNCTION'
2423
2424FUNCTION is called with one parameter, the same list BINDING in which
2425FUNCTION is specified as the filter. The value FUNCTION returns is
2426used instead of BINDING to display this item.
79214ddf 2427
a933dad1
DL
2428`:button (TYPE SELECTED)'
2429
2430TYPE must be one of `:radio' or `:toggle'. SELECTED is evaluated
2431and specifies whether the button is selected (pressed) or not.
79214ddf 2432
a933dad1
DL
2433`:image IMAGES'
2434
2435IMAGES is either a single image specification or a vector of four
2436image specifications. If it is a vector, this table lists the
2437meaning of each of the four elements:
2438
2439 Index Use when item is
2440 ----------------------------------------
2441 0 enabled and selected
2442 1 enabled and deselected
2443 2 disabled and selected
2444 3 disabled and deselected
79214ddf 2445
a933dad1 2446`:help HELP-STRING'.
79214ddf 2447
a933dad1
DL
2448Gives a help string to display for the tool bar item. This help
2449is displayed when the mouse is moved over the item.
2450
2451*** Tool-bar-related variables.
2452
2453If `auto-resize-tool-bar' is non-nil, the tool bar will automatically
2454resize to show all defined tool bar items. It will never grow larger
2455than 1/4 of the frame's size.
2456
79214ddf 2457If `auto-raise-tool-bar-buttons' is non-nil, tool bar buttons will be
a933dad1
DL
2458raised when the mouse moves over them.
2459
2460You can add extra space between tool bar items by setting
2461`tool-bar-button-margin' to a positive integer specifying a number of
2462pixels. Default is 1.
2463
2464You can change the shadow thickness of tool bar buttons by setting
2465`tool-bar-button-relief' to an integer. Default is 3.
2466
2467*** Tool-bar clicks with modifiers.
2468
2469You can bind commands to clicks with control, shift, meta etc. on
79214ddf 2470a tool bar item. If
a933dad1
DL
2471
2472 (define-key global-map [tool-bar shell]
2473 '(menu-item "Shell" shell
2474 :image (image :type xpm :file "shell.xpm")))
2475
2476is the original tool bar item definition, then
2477
2478 (define-key global-map [tool-bar S-shell] 'some-command)
2479
2480makes a binding to run `some-command' for a shifted click on the same
2481item.
2482
2483** Mode line changes.
2484
2485+++
2486*** Mouse-sensitive mode line.
2487
2488The mode line can be made mouse-sensitive by displaying strings there
2489that have a `local-map' text property. There are three ways to display
2490a string with a `local-map' property in the mode line.
2491
24921. The mode line spec contains a variable whose string value has
2493a `local-map' text property.
2494
24952. The mode line spec contains a format specifier (e.g. `%12b'), and
2496that format specifier has a `local-map' property.
2497
24983. The mode line spec contains a list containing `:eval FORM'. FORM
2499is evaluated. If the result is a string, and that string has a
2500`local-map' property.
2501
2502The same mechanism is used to determine the `face' and `help-echo'
2503properties of strings in the mode line. See `bindings.el' for an
2504example.
2505
54522c9f
GM
2506*** If a mode line element has the form `(:eval FORM)', FORM is
2507evaluated and the result is used as mode line element.
2508
a933dad1
DL
2509+++
2510*** You can suppress mode-line display by setting the buffer-local
2511variable mode-line-format to nil.
2512
2513+++
2514*** A headerline can now be displayed at the top of a window.
2515
2516This mode line's contents are controlled by the new variable
2517`header-line-format' and `default-header-line-format' which are
2518completely analogous to `mode-line-format' and
2519`default-mode-line-format'. A value of nil means don't display a top
2520line.
2521
2522The appearance of top mode lines is controlled by the face
2523`header-line'.
2524
2525The function `coordinates-in-window-p' returns `header-line' for a
2526position in the header-line.
2527
2528+++
2529** Text property `display'
2530
2531The `display' text property is used to insert images into text, and
2532also control other aspects of how text displays. The value of the
2533`display' property should be a display specification, as described
2534below, or a list or vector containing display specifications.
2535
2536*** Variable width and height spaces
2537
2538To display a space of fractional width or height, use a display
2539specification of the form `(LOCATION STRECH)'. If LOCATION is
2540`(margin left-margin)', the space is displayed in the left marginal
2541area, if it is `(margin right-margin)', it is displayed in the right
2542marginal area, and if LOCATION is `(margin nil)' the space is
2543displayed in the text. In the latter case you can also use the
2544simpler form STRETCH as property value.
2545
2546The stretch specification STRETCH itself is a list of the form `(space
2547PROPS)', where PROPS is a property list which can contain the
2548properties described below.
2549
2550The display of the fractional space replaces the display of the
2551characters having the `display' property.
2552
2553- :width WIDTH
2554
2555Specifies that the space width should be WIDTH times the normal
2556character width. WIDTH can be an integer or floating point number.
2557
2558- :relative-width FACTOR
2559
2560Specifies that the width of the stretch should be computed from the
2561first character in a group of consecutive characters that have the
2562same `display' property. The computation is done by multiplying the
2563width of that character by FACTOR.
2564
2565- :align-to HPOS
2566
2567Specifies that the space should be wide enough to reach HPOS. The
2568value HPOS is measured in units of the normal character width.
2569
2570Exactly one of the above properties should be used.
2571
2572- :height HEIGHT
2573
2574Specifies the height of the space, as HEIGHT, measured in terms of the
2575normal line height.
2576
2577- :relative-height FACTOR
2578
2579The height of the space is computed as the product of the height
2580of the text having the `display' property and FACTOR.
2581
2582- :ascent ASCENT
2583
2584Specifies that ASCENT percent of the height of the stretch should be
2585used for the ascent of the stretch, i.e. for the part above the
2586baseline. The value of ASCENT must be a non-negative number less or
2587equal to 100.
2588
2589You should not use both `:height' and `:relative-height' together.
2590
2591*** Images
2592
2593A display specification for an image has the form `(LOCATION
2594. IMAGE)', where IMAGE is an image specification. The image replaces,
2595in the display, the characters having this display specification in
2596their `display' text property. If LOCATION is `(margin left-margin)',
2597the image will be displayed in the left marginal area, if it is
2598`(margin right-margin)' it will be displayed in the right marginal
2599area, and if LOCATION is `(margin nil)' the image will be displayed in
2600the text. In the latter case you can also use the simpler form IMAGE
2601as display specification.
2602
2603*** Other display properties
2604
2605- :space-width FACTOR
2606
2607Specifies that space characters in the text having that property
2608should be displayed FACTOR times as wide as normal; FACTOR must be an
2609integer or float.
2610
2611- :height HEIGHT
2612
2613Display text having this property in a font that is smaller or larger.
2614
2615If HEIGHT is a list of the form `(+ N)', where N is an integer, that
2616means to use a font that is N steps larger. If HEIGHT is a list of
2617the form `(- N)', that means to use a font that is N steps smaller. A
2618``step'' is defined by the set of available fonts; each size for which
2619a font is available counts as a step.
2620
2621If HEIGHT is a number, that means to use a font that is HEIGHT times
2622as tall as the frame's default font.
2623
2624If HEIGHT is a symbol, it is called as a function with the current
2625height as argument. The function should return the new height to use.
2626
2627Otherwise, HEIGHT is evaluated to get the new height, with the symbol
2628`height' bound to the current specified font height.
2629
2630- :raise FACTOR
2631
2632FACTOR must be a number, specifying a multiple of the current
2633font's height. If it is positive, that means to display the characters
2634raised. If it is negative, that means to display them lower down. The
2635amount of raising or lowering is computed without taking account of the
2636`:height' subproperty.
2637
2638*** Conditional display properties
2639
2640All display specifications can be conditionalized. If a specification
2641has the form `(:when CONDITION . SPEC)', the specification SPEC
2642applies only when CONDITION yields a non-nil value when evaluated.
2643During evaluattion, point is temporarily set to the end position of
2644the text having the `display' property.
2645
2646The normal specification consisting of SPEC only is equivalent to
2647`(:when t SPEC)'.
2648
2649+++
2650** New menu separator types.
2651
2652Emacs now supports more than one menu separator type. Menu items with
2653item names consisting of dashes only (including zero dashes) are
2654treated like before. In addition, the following item names are used
2655to specify other menu separator types.
2656
2657- `--no-line' or `--space', or `--:space', or `--:noLine'
2658
2659No separator lines are drawn, but a small space is inserted where the
2660separator occurs.
2661
2662- `--single-line' or `--:singleLine'
2663
2664A single line in the menu's foreground color.
2665
2666- `--double-line' or `--:doubleLine'
2667
2668A double line in the menu's foreground color.
2669
2670- `--single-dashed-line' or `--:singleDashedLine'
2671
2672A single dashed line in the menu's foreground color.
2673
2674- `--double-dashed-line' or `--:doubleDashedLine'
2675
2676A double dashed line in the menu's foreground color.
2677
2678- `--shadow-etched-in' or `--:shadowEtchedIn'
2679
2680A single line with 3D sunken appearance. This is the the form
2681displayed for item names consisting of dashes only.
2682
2683- `--shadow-etched-out' or `--:shadowEtchedOut'
2684
2685A single line with 3D raised appearance.
2686
2687- `--shadow-etched-in-dash' or `--:shadowEtchedInDash'
2688
2689A single dashed line with 3D sunken appearance.
2690
2691- `--shadow-etched-out-dash' or `--:shadowEtchedOutDash'
2692
2693A single dashed line with 3D raise appearance.
2694
2695- `--shadow-double-etched-in' or `--:shadowDoubleEtchedIn'
2696
2697Two lines with 3D sunken appearance.
2698
2699- `--shadow-double-etched-out' or `--:shadowDoubleEtchedOut'
2700
2701Two lines with 3D raised appearance.
2702
2703- `--shadow-double-etched-in-dash' or `--:shadowDoubleEtchedInDash'
2704
2705Two dashed lines with 3D sunken appearance.
2706
2707- `--shadow-double-etched-out-dash' or `--:shadowDoubleEtchedOutDash'
2708
2709Two dashed lines with 3D raised appearance.
2710
2711Under LessTif/Motif, the last four separator types are displayed like
2712the corresponding single-line separators.
2713
2714+++
2715** New frame parameters for scroll bar colors.
2716
2717The new frame parameters `scroll-bar-foreground' and
2718`scroll-bar-background' can be used to change scroll bar colors.
2719Their value must be either a color name, a string, or nil to specify
2720that scroll bars should use a default color. For toolkit scroll bars,
2721default colors are toolkit specific. For non-toolkit scroll bars, the
2722default background is the background color of the frame, and the
2723default foreground is black.
2724
2725The X resource name of these parameters are `scrollBarForeground'
2726(class ScrollBarForeground) and `scrollBarBackground' (class
2727`ScrollBarBackground').
2728
2729Setting these parameters overrides toolkit specific X resource
2730settings for scroll bar colors.
2731
2732+++
2733** You can set `redisplay-dont-pause' to a non-nil value to prevent
2734display updates from being interrupted when input is pending.
2735
2736---
2737** Changing a window's width may now change its window start if it
2738starts on a continuation line. The new window start is computed based
2739on the window's new width, starting from the start of the continued
2740line as the start of the screen line with the minimum distance from
2741the original window start.
2742
2743---
2744** The variable `hscroll-step' and the functions
2745`hscroll-point-visible' and `hscroll-window-column' have been removed
2746now that proper horizontal scrolling is implemented.
2747
2748+++
2749** Windows can now be made fixed-width and/or fixed-height.
2750
2751A window is fixed-size if its buffer has a buffer-local variable
2752`window-size-fixed' whose value is not nil. A value of `height' makes
2753windows fixed-height, a value of `width' makes them fixed-width, any
2754other non-nil value makes them both fixed-width and fixed-height.
2755
2756The following code makes all windows displaying the current buffer
2757fixed-width and fixed-height.
2758
2759 (set (make-local-variable 'window-size-fixed) t)
2760
2761A call to enlarge-window on a window gives an error if that window is
2762fixed-width and it is tried to change the window's width, or if the
2763window is fixed-height, and it is tried to change its height. To
2764change the size of a fixed-size window, bind `window-size-fixed'
2765temporarily to nil, for example
2766
2767 (let ((window-size-fixed nil))
2768 (enlarge-window 10))
2769
79214ddf 2770Likewise, an attempt to split a fixed-height window vertically,
a933dad1 2771or a fixed-width window horizontally results in a error.
e411ce4b
EZ
2772
2773** The cursor-type frame parameter is now supported on MS-DOS
2774terminals. When Emacs starts, it by default changes the cursor shape
2775to a solid box, as it does on Unix. The `cursor-type' frame parameter
2776overrides this as it does on Unix, except that the bar cursor is
2777horizontal rather than vertical (since the MS-DOS display doesn't
2778support a vertical-bar cursor).
e33b0397
DL
2779^L
2780* Emacs 20.5 is a bug-fix release with no user-visible changes.
2781
2782** Not new, but not mentioned before:
2783M-w when Transient Mark mode is enabled disables the mark.
a933dad1
DL
2784\f
2785* Changes in Emacs 20.4
2786
2787** Init file may be called .emacs.el.
2788
2789You can now call the Emacs init file `.emacs.el'.
2790Formerly the name had to be `.emacs'. If you use the name
2791`.emacs.el', you can byte-compile the file in the usual way.
2792
2793If both `.emacs' and `.emacs.el' exist, the latter file
2794is the one that is used.
2795
2796** shell-command, and shell-command-on-region, now return
2797the exit code of the command (unless it is asynchronous).
2798Also, you can specify a place to put the error output,
2799separate from the command's regular output.
2800Interactively, the variable shell-command-default-error-buffer
2801says where to put error output; set it to a buffer name.
2802In calls from Lisp, an optional argument ERROR-BUFFER specifies
2803the buffer name.
2804
2805When you specify a non-nil error buffer (or buffer name), any error
2806output is inserted before point in that buffer, with \f\n to separate
2807it from the previous batch of error output. The error buffer is not
2808cleared, so error output from successive commands accumulates there.
2809
2810** Setting the default value of enable-multibyte-characters to nil in
2811the .emacs file, either explicitly using setq-default, or via Custom,
2812is now essentially equivalent to using --unibyte: all buffers
2813created during startup will be made unibyte after loading .emacs.
2814
2815** C-x C-f now handles the wildcards * and ? in file names. For
2816example, typing C-x C-f c*.c RET visits all the files whose names
2817match c*.c. To visit a file whose name contains * or ?, add the
2818quoting sequence /: to the beginning of the file name.
2819
2820** The M-x commands keep-lines, flush-lines and count-matches
2821now have the same feature as occur and query-replace:
2822if the pattern contains any upper case letters, then
2823they never ignore case.
2824
2825** The end-of-line format conversion feature previously mentioned
2826under `* Emacs 20.1 changes for MS-DOS and MS-Windows' actually
2827applies to all operating systems. Emacs recognizes from the contents
2828of a file what convention it uses to separate lines--newline, CRLF, or
2829just CR--and automatically converts the contents to the normal Emacs
2830convention (using newline to separate lines) for editing. This is a
2831part of the general feature of coding system conversion.
2832
2833If you subsequently save the buffer, Emacs converts the text back to
2834the same format that was used in the file before.
2835
2836You can turn off end-of-line conversion by setting the variable
2837`inhibit-eol-conversion' to non-nil, e.g. with Custom in the MULE group.
2838
2839** The character set property `prefered-coding-system' has been
2840renamed to `preferred-coding-system', for the sake of correct spelling.
2841This is a fairly internal feature, so few programs should be affected.
2842
2843** Mode-line display of end-of-line format is changed.
2844The indication of the end-of-line format of the file visited by a
2845buffer is now more explicit when that format is not the usual one for
2846your operating system. For example, the DOS-style end-of-line format
2847is displayed as "(DOS)" on Unix and GNU/Linux systems. The usual
2848end-of-line format is still displayed as a single character (colon for
2849Unix, backslash for DOS and Windows, and forward slash for the Mac).
2850
2851The values of the variables eol-mnemonic-unix, eol-mnemonic-dos,
2852eol-mnemonic-mac, and eol-mnemonic-undecided, which are strings,
2853control what is displayed in the mode line for each end-of-line
2854format. You can now customize these variables.
2855
2856** In the previous version of Emacs, tar-mode didn't work well if a
2857filename contained non-ASCII characters. Now this is fixed. Such a
2858filename is decoded by file-name-coding-system if the default value of
2859enable-multibyte-characters is non-nil.
2860
2861** The command temp-buffer-resize-mode toggles a minor mode
2862in which temporary buffers (such as help buffers) are given
2863windows just big enough to hold the whole contents.
2864
2865** If you use completion.el, you must now run the function
2866dynamic-completion-mode to enable it. Just loading the file
2867doesn't have any effect.
2868
2869** In Flyspell mode, the default is now to make just one Ispell process,
2870not one per buffer.
2871
2872** If you use iswitchb but do not call (iswitchb-default-keybindings) to
2873use the default keybindings, you will need to add the following line:
2874 (add-hook 'minibuffer-setup-hook 'iswitchb-minibuffer-setup)
2875
2876** Auto-show mode is no longer enabled just by loading auto-show.el.
2877To control it, set `auto-show-mode' via Custom or use the
2878`auto-show-mode' command.
2879
2880** Handling of X fonts' ascent/descent parameters has been changed to
2881avoid redisplay problems. As a consequence, compared with previous
2882versions the line spacing and frame size now differ with some font
2883choices, typically increasing by a pixel per line. This change
2884occurred in version 20.3 but was not documented then.
2885
2886** If you select the bar cursor style, it uses the frame's
2887cursor-color, rather than the cursor foreground pixel.
2888
2889** In multibyte mode, Rmail decodes incoming MIME messages using the
2890character set specified in the message. If you want to disable this
2891feature, set the variable rmail-decode-mime-charset to nil.
2892
2893** Not new, but not mentioned previously in NEWS: when you use #! at
2894the beginning of a file to make it executable and specify an
2895interpreter program, Emacs looks on the second line for the -*- mode
2896and variable specification, as well as on the first line.
2897
2898** Support for IBM codepage encoding of non-ASCII characters.
2899
2900The new command M-x codepage-setup creates a special coding system
2901that can be used to convert text between a specific IBM codepage and
2902one of the character sets built into Emacs which matches that
2903codepage. For example, codepage 850 corresponds to Latin-1 character
2904set, codepage 855 corresponds to Cyrillic-ISO character set, etc.
2905
2906Windows codepages 1250, 1251 and some others, where Windows deviates
2907from the corresponding ISO character set, are also supported.
2908
2909IBM box-drawing characters and other glyphs which don't have
2910equivalents in the corresponding ISO character set, are converted to
2911a character defined by dos-unsupported-char-glyph on MS-DOS, and to
2912`?' on other systems.
2913
2914IBM codepages are widely used on MS-DOS and MS-Windows, so this
2915feature is most useful on those platforms, but it can also be used on
2916Unix.
2917
2918Emacs compiled for MS-DOS automatically loads the support for the
2919current codepage when it starts.
2920
2921** Mail changes
2922
feab4fba
GM
2923*** When mail is sent using compose-mail (C-x m), and if
2924`mail-send-nonascii' is set to the new default value `mime',
2925appropriate MIME headers are added. The headers are added only if
2926non-ASCII characters are present in the body of the mail, and no other
2927MIME headers are already present. For example, the following three
2928headers are added if the coding system used in the *mail* buffer is
2929latin-1:
2930
2931 MIME-version: 1.0
2932 Content-type: text/plain; charset=iso-8859-1
2933 Content-Transfer-Encoding: 8bit
2934
a933dad1
DL
2935*** The new variable default-sendmail-coding-system specifies the
2936default way to encode outgoing mail. This has higher priority than
2937default-buffer-file-coding-system but has lower priority than
2938sendmail-coding-system and the local value of
2939buffer-file-coding-system.
2940
2941You should not set this variable manually. Instead, set
2942sendmail-coding-system to specify a fixed encoding for all outgoing
2943mail.
2944
2945*** When you try to send a message that contains non-ASCII characters,
2946if the coding system specified by those variables doesn't handle them,
2947Emacs will ask you to select a suitable coding system while showing a
2948list of possible coding systems.
2949
2950** CC Mode changes
2951
2952*** c-default-style can now take an association list that maps major
2953modes to style names. When this variable is an alist, Java mode no
2954longer hardcodes a setting to "java" style. See the variable's
2955docstring for details.
2956
2957*** It's now possible to put a list as the offset on a syntactic
2958symbol. The list is evaluated recursively until a non-nil offset is
2959found. This is useful to combine several lineup functions to act in a
2960prioritized order on a single line. However, none of the supplied
2961lineup functions use this feature currently.
2962
2963*** New syntactic symbol catch-clause, which is used on the "catch" and
2964"finally" lines in try-catch constructs in C++ and Java.
2965
2966*** New cleanup brace-catch-brace on c-cleanup-list, which does for
2967"catch" lines what brace-elseif-brace does for "else if" lines.
2968
2969*** The braces of Java anonymous inner classes are treated separately
2970from the braces of other classes in auto-newline mode. Two new
2971symbols inexpr-class-open and inexpr-class-close may be used on
2972c-hanging-braces-alist to control the automatic newlines used for
2973anonymous classes.
2974
2975*** Support for the Pike language added, along with new Pike specific
2976syntactic symbols: inlambda, lambda-intro-cont
2977
2978*** Support for Java anonymous classes via new syntactic symbol
2979inexpr-class. New syntactic symbol inexpr-statement for Pike
2980support and gcc-style statements inside expressions. New lineup
2981function c-lineup-inexpr-block.
2982
2983*** New syntactic symbol brace-entry-open which is used in brace lists
2984(i.e. static initializers) when a list entry starts with an open
2985brace. These used to be recognized as brace-list-entry's.
2986c-electric-brace also recognizes brace-entry-open braces
2987(brace-list-entry's can no longer be electrified).
2988
2989*** New command c-indent-line-or-region, not bound by default.
2990
2991*** `#' is only electric when typed in the indentation of a line.
2992
2993*** Parentheses are now electric (via the new command c-electric-paren)
2994for auto-reindenting lines when parens are typed.
2995
2996*** In "gnu" style, inline-open offset is now set to zero.
2997
2998*** Uniform handling of the inclass syntactic symbol. The indentation
2999associated with it is now always relative to the class opening brace.
3000This means that the indentation behavior has changed in some
3001circumstances, but only if you've put anything besides 0 on the
3002class-open syntactic symbol (none of the default styles do that).
3003
3004** Gnus changes.
3005
3006*** New functionality for using Gnus as an offline newsreader has been
3007added. A plethora of new commands and modes have been added. See the
3008Gnus manual for the full story.
3009
3010*** The nndraft backend has returned, but works differently than
3011before. All Message buffers are now also articles in the nndraft
3012group, which is created automatically.
3013
3014*** `gnus-alter-header-function' can now be used to alter header
3015values.
3016
3017*** `gnus-summary-goto-article' now accept Message-ID's.
3018
3019*** A new Message command for deleting text in the body of a message
3020outside the region: `C-c C-v'.
3021
3022*** You can now post to component group in nnvirtual groups with
3023`C-u C-c C-c'.
3024
3025*** `nntp-rlogin-program' -- new variable to ease customization.
3026
3027*** `C-u C-c C-c' in `gnus-article-edit-mode' will now inhibit
3028re-highlighting of the article buffer.
3029
3030*** New element in `gnus-boring-article-headers' -- `long-to'.
3031
3032*** `M-i' symbolic prefix command. See the section "Symbolic
3033Prefixes" in the Gnus manual for details.
3034
3035*** `L' and `I' in the summary buffer now take the symbolic prefix
3036`a' to add the score rule to the "all.SCORE" file.
3037
3038*** `gnus-simplify-subject-functions' variable to allow greater
3039control over simplification.
3040
3041*** `A T' -- new command for fetching the current thread.
3042
3043*** `/ T' -- new command for including the current thread in the
3044limit.
3045
3046*** `M-RET' is a new Message command for breaking cited text.
3047
3048*** \\1-expressions are now valid in `nnmail-split-methods'.
3049
79214ddf 3050*** The `custom-face-lookup' function has been removed.
a933dad1
DL
3051If you used this function in your initialization files, you must
3052rewrite them to use `face-spec-set' instead.
3053
3054*** Cancelling now uses the current select method. Symbolic prefix
3055`a' forces normal posting method.
3056
3057*** New command to translate M******** sm*rtq**t*s into proper text
3058-- `W d'.
3059
3060*** For easier debugging of nntp, you can set `nntp-record-commands'
3061to a non-nil value.
3062
3063*** nntp now uses ~/.authinfo, a .netrc-like file, for controlling
3064where and how to send AUTHINFO to NNTP servers.
3065
3066*** A command for editing group parameters from the summary buffer
3067has been added.
3068
3069*** A history of where mails have been split is available.
3070
3071*** A new article date command has been added -- `article-date-iso8601'.
3072
3073*** Subjects can be simplified when threading by setting
3074`gnus-score-thread-simplify'.
3075
3076*** A new function for citing in Message has been added --
3077`message-cite-original-without-signature'.
3078
3079*** `article-strip-all-blank-lines' -- new article command.
3080
3081*** A new Message command to kill to the end of the article has
3082been added.
3083
3084*** A minimum adaptive score can be specified by using the
3085`gnus-adaptive-word-minimum' variable.
3086
3087*** The "lapsed date" article header can be kept continually
3088updated by the `gnus-start-date-timer' command.
3089
3090*** Web listserv archives can be read with the nnlistserv backend.
3091
3092*** Old dejanews archives can now be read by nnweb.
3093
3094*** `gnus-posting-styles' has been re-activated.
3095
3096** Changes to TeX and LaTeX mode
3097
3098*** The new variable `tex-start-options-string' can be used to give
3099options for the TeX run. The default value causes TeX to run in
3100nonstopmode. For an interactive TeX run set it to nil or "".
3101
3102*** The command `tex-feed-input' sends input to the Tex Shell. In a
3103TeX buffer it is bound to the keys C-RET, C-c RET, and C-c C-m (some
3104of these keys may not work on all systems). For instance, if you run
3105TeX interactively and if the TeX run stops because of an error, you
3106can continue it without leaving the TeX buffer by typing C-RET.
3107
3108*** The Tex Shell Buffer is now in `compilation-shell-minor-mode'.
3109All error-parsing commands of the Compilation major mode are available
3110but bound to keys that don't collide with the shell. Thus you can use
3111the Tex Shell for command line executions like a usual shell.
3112
3113*** The commands `tex-validate-region' and `tex-validate-buffer' check
3114the matching of braces and $'s. The errors are listed in a *Occur*
3115buffer and you can use C-c C-c or mouse-2 to go to a particular
3116mismatch.
3117
3118** Changes to RefTeX mode
3119
3120*** The table of contents buffer can now also display labels and
3121file boundaries in addition to sections. Use `l', `i', and `c' keys.
3122
3123*** Labels derived from context (the section heading) are now
3124lowercase by default. To make the label legal in LaTeX, latin-1
3125characters will lose their accent. All Mule characters will be
3126removed from the label.
3127
3128*** The automatic display of cross reference information can also use
3129a window instead of the echo area. See variable `reftex-auto-view-crossref'.
3130
3131*** kpsewhich can be used by RefTeX to find TeX and BibTeX files. See the
3132customization group `reftex-finding-files'.
3133
3134*** The option `reftex-bibfile-ignore-list' has been renamed to
3135`reftex-bibfile-ignore-regexps' and indeed can be fed with regular
79214ddf 3136expressions.
a933dad1
DL
3137
3138*** Multiple Selection buffers are now hidden buffers.
3139
3140** New/deleted modes and packages
3141
3142*** The package snmp-mode.el provides major modes for editing SNMP and
3143SNMPv2 MIBs. It has entries on `auto-mode-alist'.
3144
3145*** The package sql.el provides a major mode, M-x sql-mode, for
3146editing SQL files, and M-x sql-interactive-mode for interacting with
3147SQL interpreters. It has an entry on `auto-mode-alist'.
3148
3149*** M-x highlight-changes-mode provides a minor mode displaying buffer
3150changes with a special face.
3151
3152*** ispell4.el has been deleted. It got in the way of ispell.el and
3153this was hard to fix reliably. It has long been obsolete -- use
3154Ispell 3.1 and ispell.el.
3155\f
3156* MS-DOS changes in Emacs 20.4
3157
3158** Emacs compiled for MS-DOS now supports MULE features better.
3159This includes support for display of all ISO 8859-N character sets,
3160conversion to and from IBM codepage encoding of non-ASCII characters,
3161and automatic setup of the MULE environment at startup. For details,
3162check out the section `MS-DOS and MULE' in the manual.
3163
3164The MS-DOS installation procedure automatically configures and builds
3165Emacs with input method support if it finds an unpacked Leim
3166distribution when the config.bat script is run.
3167
3168** Formerly, the value of lpr-command did not affect printing on
3169MS-DOS unless print-region-function was set to nil, but now it
3170controls whether an external program is invoked or output is written
3171directly to a printer port. Similarly, in the previous version of
3172Emacs, the value of ps-lpr-command did not affect PostScript printing
3173on MS-DOS unless ps-printer-name was set to something other than a
3174string (eg. t or `pipe'), but now it controls whether an external
3175program is used. (These changes were made so that configuration of
3176printing variables would be almost identical across all platforms.)
3177
3178** In the previous version of Emacs, PostScript and non-PostScript
3179output was piped to external programs, but because most print programs
3180available for MS-DOS and MS-Windows cannot read data from their standard
3181input, on those systems the data to be output is now written to a
3182temporary file whose name is passed as the last argument to the external
3183program.
3184
3185An exception is made for `print', a standard program on Windows NT,
3186and `nprint', a standard program on Novell Netware. For both of these
3187programs, the command line is constructed in the appropriate syntax
3188automatically, using only the value of printer-name or ps-printer-name
3189as appropriate--the value of the relevant `-switches' variable is
3190ignored, as both programs have no useful switches.
3191
3192** The value of the variable dos-printer (cf. dos-ps-printer), if it has
3193a value, overrides the value of printer-name (cf. ps-printer-name), on
3194MS-DOS and MS-Windows only. This has been true since version 20.3, but
3195was not documented clearly before.
3196
3197** All the Emacs games now work on MS-DOS terminals.
3198This includes Tetris and Snake.
3199\f
3200* Lisp changes in Emacs 20.4
3201
3202** New functions line-beginning-position and line-end-position
3203return the position of the beginning or end of the current line.
3204They both accept an optional argument, which has the same
3205meaning as the argument to beginning-of-line or end-of-line.
3206
3207** find-file and allied functions now have an optional argument
3208WILDCARD. If this is non-nil, they do wildcard processing,
3209and visit all files that match the wildcard pattern.
3210
3211** Changes in the file-attributes function.
3212
3213*** The file size returned by file-attributes may be an integer or a float.
3214It is an integer if the size fits in a Lisp integer, float otherwise.
3215
3216*** The inode number returned by file-attributes may be an integer (if
3217the number fits in a Lisp integer) or a cons cell containing two
3218integers.
3219
3220** The new function directory-files-and-attributes returns a list of
3221files in a directory and their attributes. It accepts the same
3222arguments as directory-files and has similar semantics, except that
3223file names and attributes are returned.
3224
3225** The new function file-attributes-lessp is a helper function for
3226sorting the list generated by directory-files-and-attributes. It
3227accepts two arguments, each a list of a file name and its atttributes.
3228It compares the file names of each according to string-lessp and
3229returns the result.
3230
3231** The new function file-expand-wildcards expands a wildcard-pattern
3232to produce a list of existing files that match the pattern.
3233
3234** New functions for base64 conversion:
3235
3236The function base64-encode-region converts a part of the buffer
3237into the base64 code used in MIME. base64-decode-region
3238performs the opposite conversion. Line-breaking is supported
3239optionally.
3240
3241Functions base64-encode-string and base64-decode-string do a similar
3242job on the text in a string. They return the value as a new string.
3243
3244**
3245The new function process-running-child-p
3246will tell you if a subprocess has given control of its
3247terminal to its own child process.
3248
3249** interrupt-process and such functions have a new feature:
3250when the second argument is `lambda', they send a signal
3251to the running child of the subshell, if any, but if the shell
3252itself owns its terminal, no signal is sent.
3253
3254** There are new widget types `plist' and `alist' which can
3255be used for customizing variables whose values are plists or alists.
3256
3257** easymenu.el Now understands `:key-sequence' and `:style button'.
3258:included is an alias for :visible.
3259
3260easy-menu-add-item now understands the values returned by
3261easy-menu-remove-item and easy-menu-item-present-p. This can be used
3262to move or copy menu entries.
3263
3264** Multibyte editing changes
3265
3266*** The definitions of sref and char-bytes are changed. Now, sref is
3267an alias of aref and char-bytes always returns 1. This change is to
3268make some Emacs Lisp code which works on 20.2 and earlier also
3269work on the latest Emacs. Such code uses a combination of sref and
3270char-bytes in a loop typically as below:
3271 (setq char (sref str idx)
3272 idx (+ idx (char-bytes idx)))
3273The byte-compiler now warns that this is obsolete.
3274
3275If you want to know how many bytes a specific multibyte character
3276(say, CH) occupies in a multibyte buffer, use this code:
3277 (charset-bytes (char-charset ch))
3278
3279*** In multibyte mode, when you narrow a buffer to some region, and the
3280region is preceded or followed by non-ASCII codes, inserting or
3281deleting at the head or the end of the region may signal this error:
3282
3283 Byte combining across boundary of accessible buffer text inhibitted
3284
3285This is to avoid some bytes being combined together into a character
3286across the boundary.
3287
3288*** The functions find-charset-region and find-charset-string include
3289`unknown' in the returned list in the following cases:
3290 o The current buffer or the target string is unibyte and
3291 contains 8-bit characters.
3292 o The current buffer or the target string is multibyte and
3293 contains invalid characters.
3294
3295*** The functions decode-coding-region and encode-coding-region remove
3296text properties of the target region. Ideally, they should correctly
3297preserve text properties, but for the moment, it's hard. Removing
3298text properties is better than preserving them in a less-than-correct
3299way.
3300
3301*** prefer-coding-system sets EOL conversion of default coding systems.
3302If the argument to prefer-coding-system specifies a certain type of
3303end of line conversion, the default coding systems set by
3304prefer-coding-system will specify that conversion type for end of line.
3305
3306*** The new function thai-compose-string can be used to properly
3307compose Thai characters in a string.
3308
3309** The primitive `define-prefix-command' now takes an optional third
3310argument NAME, which should be a string. It supplies the menu name
3311for the created keymap. Keymaps created in order to be displayed as
3312menus should always use the third argument.
3313
3314** The meanings of optional second arguments for read-char,
3315read-event, and read-char-exclusive are flipped. Now the second
3316arguments are INHERIT-INPUT-METHOD. These functions use the current
3317input method (if any) if and only if INHERIT-INPUT-METHOD is non-nil.
3318
3319** The new function clear-this-command-keys empties out the contents
3320of the vector that (this-command-keys) returns. This is useful in
3321programs that read passwords, to prevent the passwords from echoing
3322inadvertently as part of the next command in certain cases.
3323
3324** The new macro `with-temp-message' displays a temporary message in
3325the echo area, while executing some Lisp code. Like `progn', it
3326returns the value of the last form, but it also restores the previous
3327echo area contents.
3328
3329 (with-temp-message MESSAGE &rest BODY)
3330
3331** The function `require' now takes an optional third argument
3332NOERROR. If it is non-nil, then there is no error if the
3333requested feature cannot be loaded.
3334
3335** In the function modify-face, an argument of (nil) for the
3336foreground color, background color or stipple pattern
79214ddf 3337means to clear out that attribute.
a933dad1
DL
3338
3339** The `outer-window-id' frame property of an X frame
3340gives the window number of the outermost X window for the frame.
3341
3342** Temporary buffers made with with-output-to-temp-buffer are now
3343read-only by default, and normally use the major mode Help mode
3344unless you put them in some other non-Fundamental mode before the
3345end of with-output-to-temp-buffer.
3346
3347** The new functions gap-position and gap-size return information on
3348the gap of the current buffer.
3349
3350** The new functions position-bytes and byte-to-position provide a way
3351to convert between character positions and byte positions in the
3352current buffer.
3353
3354** vc.el defines two new macros, `edit-vc-file' and `with-vc-file', to
3355facilitate working with version-controlled files from Lisp programs.
3356These macros check out a given file automatically if needed, and check
3357it back in after any modifications have been made.
3358\f
3359* Installation Changes in Emacs 20.3
3360
3361** The default value of load-path now includes most subdirectories of
3362the site-specific directories /usr/local/share/emacs/site-lisp and
3363/usr/local/share/emacs/VERSION/site-lisp, in addition to those
3364directories themselves. Both immediate subdirectories and
3365subdirectories multiple levels down are added to load-path.
3366
3367Not all subdirectories are included, though. Subdirectories whose
3368names do not start with a letter or digit are excluded.
3369Subdirectories named RCS or CVS are excluded. Also, a subdirectory
3370which contains a file named `.nosearch' is excluded. You can use
3371these methods to prevent certain subdirectories from being searched.
3372
3373Emacs finds these subdirectories and adds them to load-path when it
3374starts up. While it would be cleaner to find the subdirectories each
3375time Emacs loads a file, that would be much slower.
3376
3377This feature is an incompatible change. If you have stored some Emacs
3378Lisp files in a subdirectory of the site-lisp directory specifically
3379to prevent them from being used, you will need to rename the
3380subdirectory to start with a non-alphanumeric character, or create a
3381`.nosearch' file in it, in order to continue to achieve the desired
3382results.
3383
3384** Emacs no longer includes an old version of the C preprocessor from
3385GCC. This was formerly used to help compile Emacs with C compilers
3386that had limits on the significant length of an identifier, but in
3387fact we stopped supporting such compilers some time ago.
3388\f
3389* Changes in Emacs 20.3
3390
3391** The new command C-x z (repeat) repeats the previous command
3392including its argument. If you repeat the z afterward,
3393it repeats the command additional times; thus, you can
3394perform many repetitions with one keystroke per repetition.
3395
3396** Emacs now supports "selective undo" which undoes only within a
3397specified region. To do this, set point and mark around the desired
3398region and type C-u C-x u (or C-u C-_). You can then continue undoing
3399further, within the same region, by repeating the ordinary undo
3400command C-x u or C-_. This will keep undoing changes that were made
3401within the region you originally specified, until either all of them
3402are undone, or it encounters a change which crosses the edge of that
3403region.
3404
3405In Transient Mark mode, undoing when a region is active requests
3406selective undo.
3407
3408** If you specify --unibyte when starting Emacs, then all buffers are
3409unibyte, except when a Lisp program specifically creates a multibyte
3410buffer. Setting the environment variable EMACS_UNIBYTE has the same
3411effect. The --no-unibyte option overrides EMACS_UNIBYTE and directs
3412Emacs to run normally in multibyte mode.
3413
3414The option --unibyte does not affect the reading of Emacs Lisp files,
3415though. If you want a Lisp file to be read in unibyte mode, use
3416-*-unibyte: t;-*- on its first line. That will force Emacs to
3417load that file in unibyte mode, regardless of how Emacs was started.
3418
3419** toggle-enable-multibyte-characters no longer has a key binding and
3420no longer appears in the menu bar. We've realized that changing the
3421enable-multibyte-characters variable in an existing buffer is
3422something that most users not do.
3423
3424** You can specify a coding system to use for the next cut or paste
3425operations through the window system with the command C-x RET X.
3426The coding system can make a difference for communication with other
3427applications.
3428
3429C-x RET x specifies a coding system for all subsequent cutting and
3430pasting operations.
3431
3432** You can specify the printer to use for commands that do printing by
3433setting the variable `printer-name'. Just what a printer name looks
3434like depends on your operating system. You can specify a different
3435printer for the Postscript printing commands by setting
3436`ps-printer-name'.
3437
3438** Emacs now supports on-the-fly spell checking by the means of a
3439minor mode. It is called M-x flyspell-mode. You don't have to remember
3440any other special commands to use it, and you will hardly notice it
3441except when you make a spelling error. Flyspell works by highlighting
3442incorrect words as soon as they are completed or as soon as the cursor
3443hits a new word.
3444
3445Flyspell mode works with whichever dictionary you have selected for
3446Ispell in Emacs. In TeX mode, it understands TeX syntax so as not
3447to be confused by TeX commands.
3448
3449You can correct a misspelled word by editing it into something
3450correct. You can also correct it, or accept it as correct, by
3451clicking on the word with Mouse-2; that gives you a pop-up menu
3452of various alternative replacements and actions.
3453
3454Flyspell mode also proposes "automatic" corrections. M-TAB replaces
3455the current misspelled word with a possible correction. If several
3456corrections are made possible, M-TAB cycles through them in
3457alphabetical order, or in order of decreasing likelihood if
3458flyspell-sort-corrections is nil.
3459
3460Flyspell mode also flags an error when a word is repeated, if
3461flyspell-mark-duplications-flag is non-nil.
3462
3463** Changes in input method usage.
3464
3465Now you can use arrow keys (right, left, down, up) for selecting among
3466the alternatives just the same way as you do by C-f, C-b, C-n, and C-p
3467respectively.
3468
3469You can use the ENTER key to accept the current conversion.
3470
3471If you type TAB to display a list of alternatives, you can select one
3472of the alternatives with Mouse-2.
3473
3474The meaning of the variable `input-method-verbose-flag' is changed so
3475that you can set it to t, nil, `default', or `complex-only'.
3476
3477 If the value is nil, extra guidance is never given.
3478
3479 If the value is t, extra guidance is always given.
3480
3481 If the value is `complex-only', extra guidance is always given only
3482 when you are using complex input methods such as chinese-py.
3483
3484 If the value is `default' (this is the default), extra guidance is
79214ddf 3485 given in the following case:
a933dad1
DL
3486 o When you are using a complex input method.
3487 o When you are using a simple input method but not in the minibuffer.
3488
3489If you are using Emacs through a very slow line, setting
3490input-method-verbose-flag to nil or to complex-only is a good choice,
3491and if you are using an input method you are not familiar with,
3492setting it to t is helpful.
3493
3494The old command select-input-method is now called set-input-method.
3495
3496In the language environment "Korean", you can use the following
3497keys:
3498 Shift-SPC toggle-korean-input-method
3499 C-F9 quail-hangul-switch-symbol-ksc
3500 F9 quail-hangul-switch-hanja
3501These key bindings are canceled when you switch to another language
3502environment.
3503
3504** The minibuffer history of file names now records the specified file
3505names, not the entire minibuffer input. For example, if the
3506minibuffer starts out with /usr/foo/, you might type in /etc/passwd to
3507get
3508
3509 /usr/foo//etc/passwd
3510
3511which stands for the file /etc/passwd.
3512
3513Formerly, this used to put /usr/foo//etc/passwd in the history list.
3514Now this puts just /etc/passwd in the history list.
3515
3516** If you are root, Emacs sets backup-by-copying-when-mismatch to t
3517at startup, so that saving a file will be sure to preserve
3518its owner and group.
3519
3520** find-func.el can now also find the place of definition of Emacs
3521Lisp variables in user-loaded libraries.
3522
3523** C-x r t (string-rectangle) now deletes the existing rectangle
3524contents before inserting the specified string on each line.
3525
3526** There is a new command delete-whitespace-rectangle
3527which deletes whitespace starting from a particular column
3528in all the lines on a rectangle. The column is specified
3529by the left edge of the rectangle.
3530
3531** You can now store a number into a register with C-u NUMBER C-x r n REG,
3532increment it by INC with C-u INC C-x r + REG (to increment by one, omit
3533C-u INC), and insert it in the buffer with C-x r g REG. This is useful
3534for writing keyboard macros.
3535
3536** The new command M-x speedbar displays a frame in which directories,
3537files, and tags can be displayed, manipulated, and jumped to. The
3538frame defaults to 20 characters in width, and is the same height as
3539the frame that it was started from. Some major modes define
3540additional commands for the speedbar, including Rmail, GUD/GDB, and
3541info.
3542
3543** query-replace-regexp is now bound to C-M-%.
3544
3545** In Transient Mark mode, when the region is active, M-x
3546query-replace and the other replace commands now operate on the region
3547contents only.
3548
3549** M-x write-region, when used interactively, now asks for
3550confirmation before overwriting an existing file. When you call
3551the function from a Lisp program, a new optional argument CONFIRM
3552says whether to ask for confirmation in this case.
3553
3554** If you use find-file-literally and the file is already visited
3555non-literally, the command asks you whether to revisit the file
3556literally. If you say no, it signals an error.
3557
3558** Major modes defined with the "derived mode" feature
3559now use the proper name for the mode hook: WHATEVER-mode-hook.
3560Formerly they used the name WHATEVER-mode-hooks, but that is
3561inconsistent with Emacs conventions.
3562
3563** shell-command-on-region (and shell-command) reports success or
3564failure if the command produces no output.
3565
3566** Set focus-follows-mouse to nil if your window system or window
3567manager does not transfer focus to another window when you just move
3568the mouse.
3569
3570** mouse-menu-buffer-maxlen has been renamed to
3571mouse-buffer-menu-maxlen to be consistent with the other related
3572function and variable names.
3573
3574** The new variable auto-coding-alist specifies coding systems for
3575reading specific files. This has higher priority than
3576file-coding-system-alist.
3577
3578** If you set the variable unibyte-display-via-language-environment to
3579t, then Emacs displays non-ASCII characters are displayed by
3580converting them to the equivalent multibyte characters according to
3581the current language environment. As a result, they are displayed
3582according to the current fontset.
3583
3584** C-q's handling of codes in the range 0200 through 0377 is changed.
3585
3586The codes in the range 0200 through 0237 are inserted as one byte of
3587that code regardless of the values of nonascii-translation-table and
3588nonascii-insert-offset.
3589
3590For the codes in the range 0240 through 0377, if
3591enable-multibyte-characters is non-nil and nonascii-translation-table
3592nor nonascii-insert-offset can't convert them to valid multibyte
3593characters, they are converted to Latin-1 characters.
3594
3595** If you try to find a file that is not read-accessible, you now get
3596an error, rather than an empty buffer and a warning.
3597
3598** In the minibuffer history commands M-r and M-s, an upper case
3599letter in the regular expression forces case-sensitive search.
3600
3601** In the *Help* buffer, cross-references to commands and variables
3602are inferred and hyperlinked. Use C-h m in Help mode for the relevant
3603command keys.
3604
3605** M-x apropos-command, with a prefix argument, no longer looks for
3606user option variables--instead it looks for noninteractive functions.
3607
3608Meanwhile, the command apropos-variable normally searches for
3609user option variables; with a prefix argument, it looks at
3610all variables that have documentation.
3611
3612** When you type a long line in the minibuffer, and the minibuffer
3613shows just one line, automatically scrolling works in a special way
3614that shows you overlap with the previous line of text. The variable
3615minibuffer-scroll-overlap controls how many characters of overlap
3616it should show; the default is 20.
3617
3618Meanwhile, Resize Minibuffer mode is still available; in that mode,
3619the minibuffer grows taller (up to a point) as needed to show the whole
3620of your input.
3621
3622** The new command M-x customize-changed-options lets you customize
3623all the options whose meanings or default values have changed in
3624recent Emacs versions. You specify a previous Emacs version number as
3625argument, and the command creates a customization buffer showing all
3626the customizable options which were changed since that version.
3627Newly added options are included as well.
3628
3629If you don't specify a particular version number argument,
3630then the customization buffer shows all the customizable options
3631for which Emacs versions of changes are recorded.
3632
3633This function is also bound to the Changed Options entry in the
3634Customize menu.
3635
3636** When you run M-x grep with a prefix argument, it figures out
3637the tag around point and puts that into the default grep command.
3638
3639** The new command M-* (pop-tag-mark) pops back through a history of
3640buffer positions from which M-. or other tag-finding commands were
3641invoked.
3642
3643** The new variable comment-padding specifies the number of spaces
3644that `comment-region' will insert before the actual text of the comment.
3645The default is 1.
3646
3647** In Fortran mode the characters `.', `_' and `$' now have symbol
3648syntax, not word syntax. Fortran mode now supports `imenu' and has
3649new commands fortran-join-line (M-^) and fortran-narrow-to-subprogram
3650(C-x n d). M-q can be used to fill a statement or comment block
3651sensibly.
3652
3653** GUD now supports jdb, the Java debugger, and pdb, the Python debugger.
3654
3655** If you set the variable add-log-keep-changes-together to a non-nil
3656value, the command `C-x 4 a' will automatically notice when you make
3657two entries in one day for one file, and combine them.
3658
3659** You can use the command M-x diary-mail-entries to mail yourself a
3660reminder about upcoming diary entries. See the documentation string
3661for a sample shell script for calling this function automatically
3662every night.
3663
3664** All you need to do, to enable use of the Desktop package, is to set
3665the variable desktop-enable to t with Custom.
3666
3667** There is no need to do anything special, now, to enable Gnus to
3668read and post multi-lingual articles.
3669
3670** Outline mode has now support for showing hidden outlines when
3671doing an isearch. In order for this to happen search-invisible should
3672be set to open (the default). If an isearch match is inside a hidden
3673outline the outline is made visible. If you continue pressing C-s and
3674the match moves outside the formerly invisible outline, the outline is
79214ddf 3675made invisible again.
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3676
3677** Mail reading and sending changes
3678
3679*** The Rmail e command now switches to displaying the whole header of
3680the message before it lets you edit the message. This is so that any
3681changes you make in the header will not be lost if you subsequently
3682toggle.
3683
3684*** The w command in Rmail, which writes the message body into a file,
3685now works in the summary buffer as well. (The command to delete the
3686summary buffer is now Q.) The default file name for the w command, if
3687the message has no subject, is stored in the variable
3688rmail-default-body-file.
3689
3690*** Most of the commands and modes that operate on mail and netnews no
3691longer depend on the value of mail-header-separator. Instead, they
3692handle whatever separator the buffer happens to use.
3693
3694*** If you set mail-signature to a value which is not t, nil, or a string,
3695it should be an expression. When you send a message, this expression
3696is evaluated to insert the signature.
3697
3698*** The new Lisp library feedmail.el (version 8) enhances processing of
3699outbound email messages. It works in coordination with other email
3700handling packages (e.g., rmail, VM, gnus) and is responsible for
3701putting final touches on messages and actually submitting them for
3702transmission. Users of the emacs program "fakemail" might be
3703especially interested in trying feedmail.
3704
3705feedmail is not enabled by default. See comments at the top of
3706feedmail.el for set-up instructions. Among the bigger features
3707provided by feedmail are:
3708
3709**** you can park outgoing messages into a disk-based queue and
3710stimulate sending some or all of them later (handy for laptop users);
3711there is also a queue for draft messages
3712
3713**** you can get one last look at the prepped outbound message and
3714be prompted for confirmation
3715
3716**** does smart filling of address headers
3717
3718**** can generate a MESSAGE-ID: line and a DATE: line; the date can be
3719the time the message was written or the time it is being sent; this
3720can make FCC copies more closely resemble copies that recipients get
3721
3722**** you can specify an arbitrary function for actually transmitting
3723the message; included in feedmail are interfaces for /bin/[r]mail,
3724/usr/lib/sendmail, and elisp smtpmail; it's easy to write a new
3725function for something else (10-20 lines of elisp)
3726
3727** Dired changes
3728
3729*** The Dired function dired-do-toggle, which toggles marked and unmarked
3730files, is now bound to "t" instead of "T".
3731
3732*** dired-at-point has been added to ffap.el. It allows one to easily
3733run Dired on the directory name at point.
3734
3735*** Dired has a new command: %g. It searches the contents of
3736files in the directory and marks each file that contains a match
3737for a specified regexp.
3738
3739** VC Changes
3740
3741*** New option vc-ignore-vc-files lets you turn off version control
3742conveniently.
3743
3744*** VC Dired has been completely rewritten. It is now much
3745faster, especially for CVS, and works very similar to ordinary
3746Dired.
3747
3748VC Dired is invoked by typing C-x v d and entering the name of the
3749directory to display. By default, VC Dired gives you a recursive
3750listing of all files at or below the given directory which are
3751currently locked (for CVS, all files not up-to-date are shown).
3752
3753You can change the listing format by setting vc-dired-recurse to nil,
3754then it shows only the given directory, and you may also set
3755vc-dired-terse-display to nil, then it shows all files under version
3756control plus the names of any subdirectories, so that you can type `i'
3757on such lines to insert them manually, as in ordinary Dired.
3758
3759All Dired commands operate normally in VC Dired, except for `v', which
3760is redefined as the version control prefix. That means you may type
3761`v l', `v =' etc. to invoke `vc-print-log', `vc-diff' and the like on
3762the file named in the current Dired buffer line. `v v' invokes
3763`vc-next-action' on this file, or on all files currently marked.
3764
3765The new command `v t' (vc-dired-toggle-terse-mode) allows you to
3766toggle between terse display (only locked files) and full display (all
79214ddf 3767VC files plus subdirectories). There is also a special command,
a933dad1
DL
3768`* l', to mark all files currently locked.
3769
3770Giving a prefix argument to C-x v d now does the same thing as in
3771ordinary Dired: it allows you to supply additional options for the ls
3772command in the minibuffer, to fine-tune VC Dired's output.
3773
3774*** Under CVS, if you merge changes from the repository into a working
3775file, and CVS detects conflicts, VC now offers to start an ediff
3776session to resolve them.
3777
3778Alternatively, you can use the new command `vc-resolve-conflicts' to
3779resolve conflicts in a file at any time. It works in any buffer that
3780contains conflict markers as generated by rcsmerge (which is what CVS
3781uses as well).
3782
3783*** You can now transfer changes between branches, using the new
3784command vc-merge (C-x v m). It is implemented for RCS and CVS. When
3785you invoke it in a buffer under version-control, you can specify
3786either an entire branch or a pair of versions, and the changes on that
3787branch or between the two versions are merged into the working file.
3788If this results in any conflicts, they may be resolved interactively,
3789using ediff.
3790
3791** Changes in Font Lock
3792
3793*** The face and variable previously known as font-lock-reference-face
3794are now called font-lock-constant-face to better reflect their typical
3795use for highlighting constants and labels. (Its face properties are
3796unchanged.) The variable font-lock-reference-face remains for now for
3797compatibility reasons, but its value is font-lock-constant-face.
3798
3799** Frame name display changes
3800
3801*** The command set-frame-name lets you set the name of the current
3802frame. You can use the new command select-frame-by-name to select and
3803raise a frame; this is mostly useful on character-only terminals, or
3804when many frames are invisible or iconified.
3805
3806*** On character-only terminal (not a window system), changing the
3807frame name is now reflected on the mode line and in the Buffers/Frames
3808menu.
3809
3810** Comint (subshell) changes
3811
3812*** In Comint modes, the commands to kill, stop or interrupt a
3813subjob now also kill pending input. This is for compatibility
3814with ordinary shells, where the signal characters do this.
3815
3816*** There are new commands in Comint mode.
3817
3818C-c C-x fetches the "next" line from the input history;
3819that is, the line after the last line you got.
3820You can use this command to fetch successive lines, one by one.
3821
3822C-c SPC accumulates lines of input. More precisely, it arranges to
3823send the current line together with the following line, when you send
3824the following line.
3825
3826C-c C-a if repeated twice consecutively now moves to the process mark,
3827which separates the pending input from the subprocess output and the
3828previously sent input.
3829
3830C-c M-r now runs comint-previous-matching-input-from-input;
3831it searches for a previous command, using the current pending input
3832as the search string.
3833
3834*** New option compilation-scroll-output can be set to scroll
3835automatically in compilation-mode windows.
3836
3837** C mode changes
3838
3839*** Multiline macros are now handled, both as they affect indentation,
3840and as recognized syntax. New syntactic symbol cpp-macro-cont is
3841assigned to second and subsequent lines of a multiline macro
79214ddf 3842definition.
a933dad1
DL
3843
3844*** A new style "user" which captures all non-hook-ified
3845(i.e. top-level) .emacs file variable settings and customizations.
3846Style "cc-mode" is an alias for "user" and is deprecated. "gnu"
3847style is still the default however.
3848
3849*** "java" style now conforms to Sun's JDK coding style.
3850
3851*** There are new commands c-beginning-of-defun, c-end-of-defun which
3852are alternatives which you could bind to C-M-a and C-M-e if you prefer
3853them. They do not have key bindings by default.
3854
3855*** New and improved implementations of M-a (c-beginning-of-statement)
3856and M-e (c-end-of-statement).
3857
3858*** C++ namespace blocks are supported, with new syntactic symbols
3859namespace-open, namespace-close, and innamespace.
3860
3861*** File local variable settings of c-file-style and c-file-offsets
3862makes the style variables local to that buffer only.
3863
3864*** New indentation functions c-lineup-close-paren,
3865c-indent-one-line-block, c-lineup-dont-change.
3866
3867*** Improvements (hopefully!) to the way CC Mode is loaded. You
3868should now be able to do a (require 'cc-mode) to get the entire
3869package loaded properly for customization in your .emacs file. A new
3870variable c-initialize-on-load controls this and is t by default.
3871
3872** Changes to hippie-expand.
3873
79214ddf 3874*** New customization variable `hippie-expand-dabbrev-skip-space'. If
a933dad1
DL
3875non-nil, trailing spaces may be included in the abbreviation to search for,
3876which then gives the same behavior as the original `dabbrev-expand'.
3877
3878*** New customization variable `hippie-expand-dabbrev-as-symbol'. If
3879non-nil, characters of syntax '_' is considered part of the word when
3880expanding dynamically.
3881
3882*** New customization variable `hippie-expand-no-restriction'. If
3883non-nil, narrowed buffers are widened before they are searched.
3884
3885*** New customization variable `hippie-expand-only-buffers'. If
3886non-empty, buffers searched are restricted to the types specified in
3887this list. Useful for example when constructing new special-purpose
3888expansion functions with `make-hippie-expand-function'.
3889
3890*** Text properties of the expansion are no longer copied.
3891
3892** Changes in BibTeX mode.
3893
3894*** Any titleword matching a regexp in the new variable
3895bibtex-autokey-titleword-ignore (case sensitive) is ignored during
3896automatic key generation. This replaces variable
3897bibtex-autokey-titleword-first-ignore, which only checked for matches
3898against the first word in the title.
3899
3900*** Autokey generation now uses all words from the title, not just
3901capitalized words. To avoid conflicts with existing customizations,
3902bibtex-autokey-titleword-ignore is set up such that words starting with
79214ddf 3903lowerkey characters will still be ignored. Thus, if you want to use
a933dad1 3904lowercase words from the title, you will have to overwrite the
79214ddf 3905bibtex-autokey-titleword-ignore standard setting.
a933dad1
DL
3906
3907*** Case conversion of names and title words for automatic key
3908generation is more flexible. Variable bibtex-autokey-preserve-case is
3909replaced by bibtex-autokey-titleword-case-convert and
3910bibtex-autokey-name-case-convert.
3911
3912** Changes in vcursor.el.
3913
3914*** Support for character terminals is available: there is a new keymap
3915and the vcursor will appear as an arrow between buffer text. A
3916variable `vcursor-interpret-input' allows input from the vcursor to be
3917entered exactly as if typed. Numerous functions, including
3918`vcursor-compare-windows', have been rewritten to improve consistency
3919in the selection of windows and corresponding keymaps.
3920
3921*** vcursor options can now be altered with M-x customize under the
3922Editing group once the package is loaded.
3923
3924*** Loading vcursor now does not define keys by default, as this is
3925generally a bad side effect. Use M-x customize to set
3926vcursor-key-bindings to t to restore the old behaviour.
3927
3928*** vcursor-auto-disable can be `copy', which turns off copying from the
3929vcursor, but doesn't disable it, after any non-vcursor command.
3930
3931** Ispell changes.
3932
79214ddf
FP
3933*** You can now spell check comments and strings in the current
3934buffer with M-x ispell-comments-and-strings. Comments and strings
a933dad1
DL
3935are identified by syntax tables in effect.
3936
3937*** Generic region skipping implemented.
3938A single buffer can be broken into a number of regions where text will
3939and will not be checked. The definitions of the regions can be user
3940defined. New applications and improvements made available by this
79214ddf 3941include:
a933dad1
DL
3942
3943 o URLs are automatically skipped
3944 o EMail message checking is vastly improved.
3945
3946*** Ispell can highlight the erroneous word even on non-window terminals.
3947
3948** Changes to RefTeX mode
3949
3950RefTeX has been updated in order to make it more usable with very
3951large projects (like a several volume math book). The parser has been
3952re-written from scratch. To get maximum speed from RefTeX, check the
3953section `Optimizations' in the manual.
3954
3955*** New recursive parser.
3956
3957The old version of RefTeX created a single large buffer containing the
3958entire multifile document in order to parse the document. The new
3959recursive parser scans the individual files.
3960
3961*** Parsing only part of a document.
79214ddf 3962
a933dad1
DL
3963Reparsing of changed document parts can now be made faster by enabling
3964partial scans. To use this feature, read the documentation string of
3965the variable `reftex-enable-partial-scans' and set the variable to t.
3966
3967 (setq reftex-enable-partial-scans t)
3968
3969*** Storing parsing information in a file.
3970
3971This can improve startup times considerably. To turn it on, use
3972
3973 (setq reftex-save-parse-info t)
3974
3975*** Using multiple selection buffers
3976
3977If the creation of label selection buffers is too slow (this happens
3978for large documents), you can reuse these buffers by setting
3979
3980 (setq reftex-use-multiple-selection-buffers t)
3981
3982*** References to external documents.
3983
3984The LaTeX package `xr' allows to cross-reference labels in external
3985documents. RefTeX can provide information about the external
3986documents as well. To use this feature, set up the \externaldocument
3987macros required by the `xr' package and rescan the document with
3988RefTeX. The external labels can then be accessed with the `x' key in
3989the selection buffer provided by `reftex-reference' (bound to `C-c )').
3990The `x' key also works in the table of contents buffer.
3991
3992*** Many more labeled LaTeX environments are recognized by default.
3993
3994The builtin command list now covers all the standard LaTeX commands,
3995and all of the major packages included in the LaTeX distribution.
3996
3997Also, RefTeX now understands the \appendix macro and changes
3998the enumeration of sections in the *toc* buffer accordingly.
3999
4000*** Mouse support for selection and *toc* buffers
4001
4002The mouse can now be used to select items in the selection and *toc*
4003buffers. See also the new option `reftex-highlight-selection'.
4004
4005*** New keymaps for selection and table of contents modes.
4006
4007The selection processes for labels and citation keys, and the table of
4008contents buffer now have their own keymaps: `reftex-select-label-map',
4009`reftex-select-bib-map', `reftex-toc-map'. The selection processes
4010have a number of new keys predefined. In particular, TAB lets you
4011enter a label with completion. Check the on-the-fly help (press `?'
4012at the selection prompt) or read the Info documentation to find out
4013more.
4014
4015*** Support for the varioref package
4016
4017The `v' key in the label selection buffer toggles \ref versus \vref.
4018
4019*** New hooks
4020
4021Three new hooks can be used to redefine the way labels, references,
4022and citations are created. These hooks are
4023`reftex-format-label-function', `reftex-format-ref-function',
4024`reftex-format-cite-function'.
4025
4026*** Citations outside LaTeX
4027
4028The command `reftex-citation' may also be used outside LaTeX (e.g. in
4029a mail buffer). See the Info documentation for details.
4030
4031*** Short context is no longer fontified.
4032
4033The short context in the label menu no longer copies the
4034fontification from the text in the buffer. If you prefer it to be
4035fontified, use
4036
4037 (setq reftex-refontify-context t)
4038
4039** file-cache-minibuffer-complete now accepts a prefix argument.
4040With a prefix argument, it does not try to do completion of
4041the file name within its directory; it only checks for other
4042directories that contain the same file name.
4043
4044Thus, given the file name Makefile, and assuming that a file
4045Makefile.in exists in the same directory, ordinary
4046file-cache-minibuffer-complete will try to complete Makefile to
4047Makefile.in and will therefore never look for other directories that
4048have Makefile. A prefix argument tells it not to look for longer
4049names such as Makefile.in, so that instead it will look for other
4050directories--just as if the name were already complete in its present
4051directory.
4052
4053** New modes and packages
4054
4055*** There is a new alternative major mode for Perl, Cperl mode.
4056It has many more features than Perl mode, and some people prefer
4057it, but some do not.
4058
4059*** There is a new major mode, M-x vhdl-mode, for editing files of VHDL
4060code.
4061
4062*** M-x which-function-mode enables a minor mode that displays the
4063current function name continuously in the mode line, as you move
4064around in a buffer.
4065
4066Which Function mode is effective in major modes which support Imenu.
4067
4068*** Gametree is a major mode for editing game analysis trees. The author
4069uses it for keeping notes about his postal Chess games, but it should
4070be helpful for other two-player games as well, as long as they have an
4071established system of notation similar to Chess.
4072
4073*** The new minor mode checkdoc-minor-mode provides Emacs Lisp
4074documentation string checking for style and spelling. The style
4075guidelines are found in the Emacs Lisp programming manual.
4076
4077*** The net-utils package makes some common networking features
4078available in Emacs. Some of these functions are wrappers around
4079system utilities (ping, nslookup, etc); others are implementations of
4080simple protocols (finger, whois) in Emacs Lisp. There are also
4081functions to make simple connections to TCP/IP ports for debugging and
4082the like.
4083
4084*** highlight-changes-mode is a minor mode that uses colors to
4085identify recently changed parts of the buffer text.
4086
4087*** The new package `midnight' lets you specify things to be done
4088within Emacs at midnight--by default, kill buffers that you have not
4089used in a considerable time. To use this feature, customize
4090the user option `midnight-mode' to t.
4091
4092*** The file generic-x.el defines a number of simple major modes.
4093
4094 apache-generic-mode: For Apache and NCSA httpd configuration files
4095 samba-generic-mode: Samba configuration files
4096 fvwm-generic-mode: For fvwm initialization files
4097 x-resource-generic-mode: For X resource files
4098 hosts-generic-mode: For hosts files (.rhosts, /etc/hosts, etc)
4099 mailagent-rules-generic-mode: For mailagent .rules files
4100 javascript-generic-mode: For JavaScript files
4101 vrml-generic-mode: For VRML files
4102 java-manifest-generic-mode: For Java MANIFEST files
4103 java-properties-generic-mode: For Java property files
4104 mailrc-generic-mode: For .mailrc files
4105
4106 Platform-specific modes:
4107
4108 prototype-generic-mode: For Solaris/Sys V prototype files
4109 pkginfo-generic-mode: For Solaris/Sys V pkginfo files
4110 alias-generic-mode: For C shell alias files
4111 inf-generic-mode: For MS-Windows INF files
4112 ini-generic-mode: For MS-Windows INI files
4113 reg-generic-mode: For MS-Windows Registry files
4114 bat-generic-mode: For MS-Windows BAT scripts
4115 rc-generic-mode: For MS-Windows Resource files
4116 rul-generic-mode: For InstallShield scripts
4117\f
4118* Lisp changes in Emacs 20.3 since the Emacs Lisp Manual was published
4119
4120** If you want a Lisp file to be read in unibyte mode,
4121use -*-unibyte: t;-*- on its first line.
4122That will force Emacs to read that file in unibyte mode.
4123Otherwise, the file will be loaded and byte-compiled in multibyte mode.
4124
4125Thus, each lisp file is read in a consistent way regardless of whether
4126you started Emacs with --unibyte, so that a Lisp program gives
4127consistent results regardless of how Emacs was started.
4128
4129** The new function assoc-default is useful for searching an alist,
4130and using a default value if the key is not found there. You can
4131specify a comparison predicate, so this function is useful for
4132searching comparing a string against an alist of regular expressions.
4133
4134** The functions unibyte-char-to-multibyte and
4135multibyte-char-to-unibyte convert between unibyte and multibyte
4136character codes, in a way that is appropriate for the current language
4137environment.
4138
4139** The functions read-event, read-char and read-char-exclusive now
4140take two optional arguments. PROMPT, if non-nil, specifies a prompt
4141string. SUPPRESS-INPUT-METHOD, if non-nil, says to disable the
4142current input method for reading this one event.
4143
4144** Two new variables print-escape-nonascii and print-escape-multibyte
4145now control whether to output certain characters as
4146backslash-sequences. print-escape-nonascii applies to single-byte
4147non-ASCII characters; print-escape-multibyte applies to multibyte
4148characters. Both of these variables are used only when printing
4149in readable fashion (prin1 uses them, princ does not).
4150\f
4151* Lisp changes in Emacs 20.3 before the Emacs Lisp Manual was published
4152
4153** Compiled Emacs Lisp files made with the modified "MBSK" version
4154of Emacs 20.2 do not work in Emacs 20.3.
4155
4156** Buffer positions are now measured in characters, as they were
4157in Emacs 19 and before. This means that (forward-char 1)
4158always increases point by 1.
4159
4160The function chars-in-region now just subtracts its arguments. It is
4161considered obsolete. The function char-boundary-p has been deleted.
4162
4163See below for additional changes relating to multibyte characters.
4164
4165** defcustom, defface and defgroup now accept the keyword `:version'.
4166Use this to specify in which version of Emacs a certain variable's
4167default value changed. For example,
4168
4169 (defcustom foo-max 34 "*Maximum number of foo's allowed."
4170 :type 'integer
4171 :group 'foo
4172 :version "20.3")
4173
79214ddf 4174 (defgroup foo-group nil "The foo group."
a933dad1
DL
4175 :version "20.3")
4176
4177If an entire new group is added or the variables in it have the
4178default values changed, then just add a `:version' to that group. It
4179is recommended that new packages added to the distribution contain a
4180`:version' in the top level group.
4181
4182This information is used to control the customize-changed-options command.
4183
4184** It is now an error to change the value of a symbol whose name
4185starts with a colon--if it is interned in the standard obarray.
4186
4187However, setting such a symbol to its proper value, which is that
4188symbol itself, is not an error. This is for the sake of programs that
4189support previous Emacs versions by explicitly setting these variables
4190to themselves.
4191
4192If you set the variable keyword-symbols-constant-flag to nil,
4193this error is suppressed, and you can set these symbols to any
4194values whatever.
4195
4196** There is a new debugger command, R.
4197It evaluates an expression like e, but saves the result
4198in the buffer *Debugger-record*.
4199
4200** Frame-local variables.
4201
4202You can now make a variable local to various frames. To do this, call
4203the function make-variable-frame-local; this enables frames to have
4204local bindings for that variable.
4205
4206These frame-local bindings are actually frame parameters: you create a
4207frame-local binding in a specific frame by calling
4208modify-frame-parameters and specifying the variable name as the
4209parameter name.
4210
4211Buffer-local bindings take precedence over frame-local bindings.
4212Thus, if the current buffer has a buffer-local binding, that binding is
4213active; otherwise, if the selected frame has a frame-local binding,
4214that binding is active; otherwise, the default binding is active.
4215
4216It would not be hard to implement window-local bindings, but it is not
4217clear that this would be very useful; windows tend to come and go in a
4218very transitory fashion, so that trying to produce any specific effect
4219through a window-local binding would not be very robust.
4220
4221** `sregexq' and `sregex' are two new functions for constructing
4222"symbolic regular expressions." These are Lisp expressions that, when
4223evaluated, yield conventional string-based regexps. The symbolic form
4224makes it easier to construct, read, and maintain complex patterns.
4225See the documentation in sregex.el.
4226
4227** parse-partial-sexp's return value has an additional element which
4228is used to pass information along if you pass it to another call to
4229parse-partial-sexp, starting its scan where the first call ended.
4230The contents of this field are not yet finalized.
4231
4232** eval-region now accepts a fourth optional argument READ-FUNCTION.
4233If it is non-nil, that function is used instead of `read'.
4234
4235** unload-feature by default removes the feature's functions from
4236known hooks to avoid trouble, but a package providing FEATURE can
4237define a hook FEATURE-unload-hook to be run by unload-feature instead.
4238
4239** read-from-minibuffer no longer returns the argument DEFAULT-VALUE
4240when the user enters empty input. It now returns the null string, as
4241it did in Emacs 19. The default value is made available in the
4242history via M-n, but it is not applied here as a default.
4243
4244The other, more specialized minibuffer-reading functions continue to
4245return the default value (not the null string) when the user enters
4246empty input.
4247
4248** The new variable read-buffer-function controls which routine to use
4249for selecting buffers. For example, if you set this variable to
4250`iswitchb-read-buffer', iswitchb will be used to read buffer names.
4251Other functions can also be used if they accept the same arguments as
4252`read-buffer' and return the selected buffer name as a string.
4253
4254** The new function read-passwd reads a password from the terminal,
4255echoing a period for each character typed. It takes three arguments:
4256a prompt string, a flag which says "read it twice to make sure", and a
4257default password to use if the user enters nothing.
4258
4259** The variable fill-nobreak-predicate gives major modes a way to
4260specify not to break a line at certain places. Its value is a
4261function which is called with no arguments, with point located at the
4262place where a break is being considered. If the function returns
4263non-nil, then the line won't be broken there.
4264
4265** window-end now takes an optional second argument, UPDATE.
4266If this is non-nil, then the function always returns an accurate
4267up-to-date value for the buffer position corresponding to the
4268end of the window, even if this requires computation.
4269
4270** other-buffer now takes an optional argument FRAME
4271which specifies which frame's buffer list to use.
4272If it is nil, that means use the selected frame's buffer list.
4273
4274** The new variable buffer-display-time, always local in every buffer,
4275holds the value of (current-time) as of the last time that a window
4276was directed to display this buffer.
4277
4278** It is now meaningful to compare two window-configuration objects
4279with `equal'. Two window-configuration objects are equal if they
4280describe equivalent arrangements of windows, in the same frame--in
4281other words, if they would give the same results if passed to
4282set-window-configuration.
4283
4284** compare-window-configurations is a new function that compares two
4285window configurations loosely. It ignores differences in saved buffer
4286positions and scrolling, and considers only the structure and sizes of
4287windows and the choice of buffers to display.
4288
4289** The variable minor-mode-overriding-map-alist allows major modes to
4290override the key bindings of a minor mode. The elements of this alist
4291look like the elements of minor-mode-map-alist: (VARIABLE . KEYMAP).
4292
4293If the VARIABLE in an element of minor-mode-overriding-map-alist has a
4294non-nil value, the paired KEYMAP is active, and totally overrides the
4295map (if any) specified for the same variable in minor-mode-map-alist.
4296
4297minor-mode-overriding-map-alist is automatically local in all buffers,
4298and it is meant to be set by major modes.
4299
4300** The function match-string-no-properties is like match-string
4301except that it discards all text properties from the result.
4302
4303** The function load-average now accepts an optional argument
4304USE-FLOATS. If it is non-nil, the load average values are returned as
4305floating point numbers, rather than as integers to be divided by 100.
4306
4307** The new variable temporary-file-directory specifies the directory
4308to use for creating temporary files. The default value is determined
4309in a reasonable way for your operating system; on GNU and Unix systems
4310it is based on the TMP and TMPDIR environment variables.
4311
4312** Menu changes
4313
4314*** easymenu.el now uses the new menu item format and supports the
4315keywords :visible and :filter. The existing keyword :keys is now
4316better supported.
4317
4318The variable `easy-menu-precalculate-equivalent-keybindings' controls
4319a new feature which calculates keyboard equivalents for the menu when
4320you define the menu. The default is t. If you rarely use menus, you
4321can set the variable to nil to disable this precalculation feature;
4322then the calculation is done only if you use the menu bar.
4323
4324*** A new format for menu items is supported.
4325
4326In a keymap, a key binding that has the format
4327 (STRING . REAL-BINDING) or (STRING HELP-STRING . REAL-BINDING)
4328defines a menu item. Now a menu item definition may also be a list that
4329starts with the symbol `menu-item'.
4330
4331The format is:
4332 (menu-item ITEM-NAME) or
4333 (menu-item ITEM-NAME REAL-BINDING . ITEM-PROPERTY-LIST)
4334where ITEM-NAME is an expression which evaluates to the menu item
4335string, and ITEM-PROPERTY-LIST has the form of a property list.
4336The supported properties include
4337
4338:enable FORM Evaluate FORM to determine whether the
4339 item is enabled.
4340:visible FORM Evaluate FORM to determine whether the
4341 item should appear in the menu.
79214ddf 4342:filter FILTER-FN
a933dad1
DL
4343 FILTER-FN is a function of one argument,
4344 which will be REAL-BINDING.
4345 It should return a binding to use instead.
4346:keys DESCRIPTION
4347 DESCRIPTION is a string that describes an equivalent keyboard
4348 binding for for REAL-BINDING. DESCRIPTION is expanded with
4349 `substitute-command-keys' before it is used.
4350:key-sequence KEY-SEQUENCE
4351 KEY-SEQUENCE is a key-sequence for an equivalent
4352 keyboard binding.
4353:key-sequence nil
4354 This means that the command normally has no
4355 keyboard equivalent.
4356:help HELP HELP is the extra help string (not currently used).
4357:button (TYPE . SELECTED)
4358 TYPE is :toggle or :radio.
4359 SELECTED is a form, to be evaluated, and its
4360 value says whether this button is currently selected.
4361
4362Buttons are at the moment only simulated by prefixes in the menu.
4363Eventually ordinary X-buttons may be supported.
4364
4365(menu-item ITEM-NAME) defines unselectable item.
4366
4367** New event types
4368
4369*** The new event type `mouse-wheel' is generated by a wheel on a
4370mouse (such as the MS Intellimouse). The event contains a delta that
4371corresponds to the amount and direction that the wheel is rotated,
4372which is typically used to implement a scroll or zoom. The format is:
4373
4374 (mouse-wheel POSITION DELTA)
4375
4376where POSITION is a list describing the position of the event in the
4377same format as a mouse-click event, and DELTA is a signed number
4378indicating the number of increments by which the wheel was rotated. A
4379negative DELTA indicates that the wheel was rotated backwards, towards
4380the user, and a positive DELTA indicates that the wheel was rotated
4381forward, away from the user.
4382
4383As of now, this event type is generated only on MS Windows.
4384
4385*** The new event type `drag-n-drop' is generated when a group of
4386files is selected in an application outside of Emacs, and then dragged
4387and dropped onto an Emacs frame. The event contains a list of
4388filenames that were dragged and dropped, which are then typically
4389loaded into Emacs. The format is:
4390
4391 (drag-n-drop POSITION FILES)
4392
4393where POSITION is a list describing the position of the event in the
4394same format as a mouse-click event, and FILES is the list of filenames
4395that were dragged and dropped.
4396
4397As of now, this event type is generated only on MS Windows.
4398
4399** Changes relating to multibyte characters.
4400
4401*** The variable enable-multibyte-characters is now read-only;
4402any attempt to set it directly signals an error. The only way
4403to change this value in an existing buffer is with set-buffer-multibyte.
4404
4405*** In a string constant, `\ ' now stands for "nothing at all". You
4406can use it to terminate a hex escape which is followed by a character
4407that could otherwise be read as part of the hex escape.
4408
4409*** String indices are now measured in characters, as they were
4410in Emacs 19 and before.
4411
4412The function chars-in-string has been deleted.
4413The function concat-chars has been renamed to `string'.
4414
4415*** The function set-buffer-multibyte sets the flag in the current
4416buffer that says whether the buffer uses multibyte representation or
4417unibyte representation. If the argument is nil, it selects unibyte
4418representation. Otherwise it selects multibyte representation.
4419
4420This function does not change the contents of the buffer, viewed
4421as a sequence of bytes. However, it does change the contents
4422viewed as characters; a sequence of two bytes which is treated as
4423one character when the buffer uses multibyte representation
4424will count as two characters using unibyte representation.
4425
4426This function sets enable-multibyte-characters to record which
4427representation is in use. It also adjusts various data in the buffer
4428(including its markers, overlays and text properties) so that they are
4429consistent with the new representation.
4430
4431*** string-make-multibyte takes a string and converts it to multibyte
4432representation. Most of the time, you don't need to care
4433about the representation, because Emacs converts when necessary;
4434however, it makes a difference when you compare strings.
4435
4436The conversion of non-ASCII characters works by adding the value of
4437nonascii-insert-offset to each character, or by translating them
4438using the table nonascii-translation-table.
4439
4440*** string-make-unibyte takes a string and converts it to unibyte
4441representation. Most of the time, you don't need to care about the
4442representation, but it makes a difference when you compare strings.
4443
4444The conversion from multibyte to unibyte representation
4445loses information; the only time Emacs performs it automatically
4446is when inserting a multibyte string into a unibyte buffer.
4447
4448*** string-as-multibyte takes a string, and returns another string
4449which contains the same bytes, but treats them as multibyte.
4450
4451*** string-as-unibyte takes a string, and returns another string
4452which contains the same bytes, but treats them as unibyte.
4453
4454*** The new function compare-strings lets you compare
4455portions of two strings. Unibyte strings are converted to multibyte,
4456so that a unibyte string can match a multibyte string.
4457You can specify whether to ignore case or not.
4458
4459*** assoc-ignore-case now uses compare-strings so that
4460it can treat unibyte and multibyte strings as equal.
4461
4462*** Regular expression operations and buffer string searches now
4463convert the search pattern to multibyte or unibyte to accord with the
4464buffer or string being searched.
4465
4466One consequence is that you cannot always use \200-\377 inside of
4467[...] to match all non-ASCII characters. This does still work when
4468searching or matching a unibyte buffer or string, but not when
4469searching or matching a multibyte string. Unfortunately, there is no
4470obvious choice of syntax to use within [...] for that job. But, what
4471you want is just to match all non-ASCII characters, the regular
4472expression [^\0-\177] works for it.
4473
4474*** Structure of coding system changed.
4475
4476All coding systems (including aliases and subsidiaries) are named
4477by symbols; the symbol's `coding-system' property is a vector
4478which defines the coding system. Aliases share the same vector
4479as the principal name, so that altering the contents of this
4480vector affects the principal name and its aliases. You can define
4481your own alias name of a coding system by the function
4482define-coding-system-alias.
4483
4484The coding system definition includes a property list of its own. Use
4485the new functions `coding-system-get' and `coding-system-put' to
4486access such coding system properties as post-read-conversion,
4487pre-write-conversion, character-translation-table-for-decode,
4488character-translation-table-for-encode, mime-charset, and
4489safe-charsets. For instance, (coding-system-get 'iso-latin-1
4490'mime-charset) gives the corresponding MIME-charset parameter
4491`iso-8859-1'.
4492
4493Among the coding system properties listed above, safe-charsets is new.
4494The value of this property is a list of character sets which this
4495coding system can correctly encode and decode. For instance:
4496(coding-system-get 'iso-latin-1 'safe-charsets) => (ascii latin-iso8859-1)
4497
4498Here, "correctly encode" means that the encoded character sets can
4499also be handled safely by systems other than Emacs as far as they
4500are capable of that coding system. Though, Emacs itself can encode
4501the other character sets and read it back correctly.
4502
4503*** The new function select-safe-coding-system can be used to find a
4504proper coding system for encoding the specified region or string.
4505This function requires a user interaction.
4506
4507*** The new functions find-coding-systems-region and
4508find-coding-systems-string are helper functions used by
4509select-safe-coding-system. They return a list of all proper coding
4510systems to encode a text in some region or string. If you don't want
4511a user interaction, use one of these functions instead of
4512select-safe-coding-system.
4513
4514*** The explicit encoding and decoding functions, such as
4515decode-coding-region and encode-coding-string, now set
4516last-coding-system-used to reflect the actual way encoding or decoding
4517was done.
4518
4519*** The new function detect-coding-with-language-environment can be
4520used to detect a coding system of text according to priorities of
4521coding systems used by some specific language environment.
4522
4523*** The functions detect-coding-region and detect-coding-string always
4524return a list if the arg HIGHEST is nil. Thus, if only ASCII
4525characters are found, they now return a list of single element
4526`undecided' or its subsidiaries.
4527
4528*** The new functions coding-system-change-eol-conversion and
4529coding-system-change-text-conversion can be used to get a different
4530coding system than what specified only in how end-of-line or text is
4531converted.
4532
4533*** The new function set-selection-coding-system can be used to set a
4534coding system for communicating with other X clients.
4535
4536*** The function `map-char-table' now passes as argument only valid
4537character codes, plus generic characters that stand for entire
4538character sets or entire subrows of a character set. In other words,
4539each time `map-char-table' calls its FUNCTION argument, the key value
4540either will be a valid individual character code, or will stand for a
4541range of characters.
4542
4543*** The new function `char-valid-p' can be used for checking whether a
4544Lisp object is a valid character code or not.
4545
4546*** The new function `charset-after' returns a charset of a character
4547in the current buffer at position POS.
4548
4549*** Input methods are now implemented using the variable
4550input-method-function. If this is non-nil, its value should be a
4551function; then, whenever Emacs reads an input event that is a printing
4552character with no modifier bits, it calls that function, passing the
4553event as an argument. Often this function will read more input, first
4554binding input-method-function to nil.
4555
4556The return value should be a list of the events resulting from input
4557method processing. These events will be processed sequentially as
4558input, before resorting to unread-command-events. Events returned by
4559the input method function are not passed to the input method function,
4560not even if they are printing characters with no modifier bits.
4561
4562The input method function is not called when reading the second and
4563subsequent events of a key sequence.
4564
4565*** You can customize any language environment by using
4566set-language-environment-hook and exit-language-environment-hook.
4567
4568The hook `exit-language-environment-hook' should be used to undo
4569customizations that you made with set-language-environment-hook. For
4570instance, if you set up a special key binding for a specific language
4571environment by set-language-environment-hook, you should set up
4572exit-language-environment-hook to restore the normal key binding.
4573\f
4574* Changes in Emacs 20.1
4575
4576** Emacs has a new facility for customization of its many user
4577options. It is called M-x customize. With this facility you can look
4578at the many user options in an organized way; they are grouped into a
4579tree structure.
4580
4581M-x customize also knows what sorts of values are legitimate for each
4582user option and ensures that you don't use invalid values.
4583
4584With M-x customize, you can set options either for the present Emacs
4585session or permanently. (Permanent settings are stored automatically
4586in your .emacs file.)
4587
4588** Scroll bars are now on the left side of the window.
4589You can change this with M-x customize-option scroll-bar-mode.
4590
4591** The mode line no longer includes the string `Emacs'.
4592This makes more space in the mode line for other information.
4593
4594** When you select a region with the mouse, it is highlighted
4595immediately afterward. At that time, if you type the DELETE key, it
4596kills the region.
4597
4598The BACKSPACE key, and the ASCII character DEL, do not do this; they
4599delete the character before point, as usual.
4600
4601** In an incremental search the whole current match is highlighted
4602on terminals which support this. (You can disable this feature
4603by setting search-highlight to nil.)
4604
4605** In the minibuffer, in some cases, you can now use M-n to
4606insert the default value into the minibuffer as text. In effect,
4607the default value (if the minibuffer routines know it) is tacked
4608onto the history "in the future". (The more normal use of the
4609history list is to use M-p to insert minibuffer input used in the
4610past.)
4611
4612** In Text mode, now only blank lines separate paragraphs.
4613This makes it possible to get the full benefit of Adaptive Fill mode
4614in Text mode, and other modes derived from it (such as Mail mode).
4615TAB in Text mode now runs the command indent-relative; this
4616makes a practical difference only when you use indented paragraphs.
4617
4618As a result, the old Indented Text mode is now identical to Text mode,
4619and is an alias for it.
4620
4621If you want spaces at the beginning of a line to start a paragraph,
4622use the new mode, Paragraph Indent Text mode.
4623
4624** Scrolling changes
4625
4626*** Scroll commands to scroll a whole screen now preserve the screen
4627position of the cursor, if scroll-preserve-screen-position is non-nil.
4628
4629In this mode, if you scroll several screens back and forth, finishing
4630on the same screen where you started, the cursor goes back to the line
4631where it started.
4632
4633*** If you set scroll-conservatively to a small number, then when you
4634move point a short distance off the screen, Emacs will scroll the
4635screen just far enough to bring point back on screen, provided that
4636does not exceed `scroll-conservatively' lines.
4637
4638*** The new variable scroll-margin says how close point can come to the
4639top or bottom of a window. It is a number of screen lines; if point
4640comes within that many lines of the top or bottom of the window, Emacs
4641recenters the window.
4642
4643** International character set support (MULE)
4644
4645Emacs now supports a wide variety of international character sets,
4646including European variants of the Latin alphabet, as well as Chinese,
4647Devanagari (Hindi and Marathi), Ethiopian, Greek, IPA, Japanese,
4648Korean, Lao, Russian, Thai, Tibetan, and Vietnamese scripts. These
4649features have been merged from the modified version of Emacs known as
4650MULE (for "MULti-lingual Enhancement to GNU Emacs")
4651
4652Users of these scripts have established many more-or-less standard
4653coding systems for storing files. Emacs uses a single multibyte
4654character encoding within Emacs buffers; it can translate from a wide
4655variety of coding systems when reading a file and can translate back
4656into any of these coding systems when saving a file.
4657
4658Keyboards, even in the countries where these character sets are used,
4659generally don't have keys for all the characters in them. So Emacs
4660supports various "input methods", typically one for each script or
4661language, to make it possible to type them.
4662
4663The Emacs internal multibyte encoding represents a non-ASCII
4664character as a sequence of bytes in the range 0200 through 0377.
4665
4666The new prefix key C-x RET is used for commands that pertain
4667to multibyte characters, coding systems, and input methods.
4668
4669You can disable multibyte character support as follows:
4670
4671 (setq-default enable-multibyte-characters nil)
4672
4673Calling the function standard-display-european turns off multibyte
4674characters, unless you specify a non-nil value for the second
4675argument, AUTO. This provides compatibility for people who are
4676already using standard-display-european to continue using unibyte
4677characters for their work until they want to change.
4678
4679*** Input methods
4680
4681An input method is a kind of character conversion which is designed
4682specifically for interactive input. In Emacs, typically each language
4683has its own input method (though sometimes several languages which use
4684the same characters can share one input method). Some languages
4685support several input methods.
4686
4687The simplest kind of input method works by mapping ASCII letters into
4688another alphabet. This is how the Greek and Russian input methods
4689work.
4690
4691A more powerful technique is composition: converting sequences of
4692characters into one letter. Many European input methods use
4693composition to produce a single non-ASCII letter from a sequence which
4694consists of a letter followed by diacritics. For example, a' is one
4695sequence of two characters that might be converted into a single
4696letter.
4697
4698The input methods for syllabic scripts typically use mapping followed
4699by conversion. The input methods for Thai and Korean work this way.
4700First, letters are mapped into symbols for particular sounds or tone
4701marks; then, sequences of these which make up a whole syllable are
4702mapped into one syllable sign--most often a "composite character".
4703
4704None of these methods works very well for Chinese and Japanese, so
4705they are handled specially. First you input a whole word using
4706phonetic spelling; then, after the word is in the buffer, Emacs
4707converts it into one or more characters using a large dictionary.
4708
4709Since there is more than one way to represent a phonetically spelled
4710word using Chinese characters, Emacs can only guess which one to use;
4711typically these input methods give you a way to say "guess again" if
4712the first guess is wrong.
4713
4714*** The command C-x RET m (toggle-enable-multibyte-characters)
4715turns multibyte character support on or off for the current buffer.
4716
4717If multibyte character support is turned off in a buffer, then each
4718byte is a single character, even codes 0200 through 0377--exactly as
4719they did in Emacs 19.34. This includes the features for support for
4720the European characters, ISO Latin-1 and ISO Latin-2.
4721
4722However, there is no need to turn off multibyte character support to
4723use ISO Latin-1 or ISO Latin-2; the Emacs multibyte character set
4724includes all the characters in these character sets, and Emacs can
4725translate automatically to and from either one.
4726
4727*** Visiting a file in unibyte mode.
4728
4729Turning off multibyte character support in the buffer after visiting a
4730file with multibyte code conversion will display the multibyte
4731sequences already in the buffer, byte by byte. This is probably not
4732what you want.
4733
4734If you want to edit a file of unibyte characters (Latin-1, for
4735example), you can do it by specifying `no-conversion' as the coding
4736system when reading the file. This coding system also turns off
4737multibyte characters in that buffer.
4738
4739If you turn off multibyte character support entirely, this turns off
4740character conversion as well.
4741
4742*** Displaying international characters on X Windows.
4743
4744A font for X typically displays just one alphabet or script.
4745Therefore, displaying the entire range of characters Emacs supports
4746requires using many fonts.
4747
4748Therefore, Emacs now supports "fontsets". Each fontset is a
4749collection of fonts, each assigned to a range of character codes.
4750
4751A fontset has a name, like a font. Individual fonts are defined by
4752the X server; fontsets are defined within Emacs itself. But once you
4753have defined a fontset, you can use it in a face or a frame just as
4754you would use a font.
4755
4756If a fontset specifies no font for a certain character, or if it
4757specifies a font that does not exist on your system, then it cannot
4758display that character. It will display an empty box instead.
4759
4760The fontset height and width are determined by the ASCII characters
4761(that is, by the font in the fontset which is used for ASCII
4762characters). If another font in the fontset has a different height,
4763or the wrong width, then characters assigned to that font are clipped,
4764and displayed within a box if highlight-wrong-size-font is non-nil.
4765
4766*** Defining fontsets.
4767
4768Emacs does not use any fontset by default. Its default font is still
4769chosen as in previous versions. You can tell Emacs to use a fontset
4770with the `-fn' option or the `Font' X resource.
4771
4772Emacs creates a standard fontset automatically according to the value
4773of standard-fontset-spec. This fontset's short name is
4774`fontset-standard'. Bold, italic, and bold-italic variants of the
4775standard fontset are created automatically.
4776
4777If you specify a default ASCII font with the `Font' resource or `-fn'
4778argument, a fontset is generated from it. This works by replacing the
4779FOUNDARY, FAMILY, ADD_STYLE, and AVERAGE_WIDTH fields of the font name
4780with `*' then using this to specify a fontset. This fontset's short
4781name is `fontset-startup'.
4782
4783Emacs checks resources of the form Fontset-N where N is 0, 1, 2...
4784The resource value should have this form:
4785 FONTSET-NAME, [CHARSET-NAME:FONT-NAME]...
4786FONTSET-NAME should have the form of a standard X font name, except:
4787 * most fields should be just the wild card "*".
4788 * the CHARSET_REGISTRY field should be "fontset"
4789 * the CHARSET_ENCODING field can be any nickname of the fontset.
4790The construct CHARSET-NAME:FONT-NAME can be repeated any number
4791of times; each time specifies the font for one character set.
4792CHARSET-NAME should be the name name of a character set, and
4793FONT-NAME should specify an actual font to use for that character set.
4794
4795Each of these fontsets has an alias which is made from the
4796last two font name fields, CHARSET_REGISTRY and CHARSET_ENCODING.
4797You can refer to the fontset by that alias or by its full name.
4798
4799For any character sets that you don't mention, Emacs tries to choose a
4800font by substituting into FONTSET-NAME. For instance, with the
4801following resource,
4802 Emacs*Fontset-0: -*-fixed-medium-r-normal-*-24-*-*-*-*-*-fontset-24
4803the font for ASCII is generated as below:
4804 -*-fixed-medium-r-normal-*-24-*-ISO8859-1
4805Here is the substitution rule:
4806 Change CHARSET_REGISTRY and CHARSET_ENCODING to that of the charset
4807 defined in the variable x-charset-registries. For instance, ASCII has
4808 the entry (ascii . "ISO8859-1") in this variable. Then, reduce
4809 sequences of wild cards -*-...-*- with a single wildcard -*-.
4810 (This is to prevent use of auto-scaled fonts.)
4811
4812The function which processes the fontset resource value to create the
4813fontset is called create-fontset-from-fontset-spec. You can also call
4814that function explicitly to create a fontset.
4815
4816With the X resource Emacs.Font, you can specify a fontset name just
4817like an actual font name. But be careful not to specify a fontset
4818name in a wildcard resource like Emacs*Font--that tries to specify the
4819fontset for other purposes including menus, and they cannot handle
4820fontsets.
4821
4822*** The command M-x set-language-environment sets certain global Emacs
4823defaults for a particular choice of language.
4824
4825Selecting a language environment typically specifies a default input
4826method and which coding systems to recognize automatically when
4827visiting files. However, it does not try to reread files you have
4828already visited; the text in those buffers is not affected. The
4829language environment may also specify a default choice of coding
4830system for new files that you create.
4831
4832It makes no difference which buffer is current when you use
4833set-language-environment, because these defaults apply globally to the
4834whole Emacs session.
4835
4836For example, M-x set-language-environment RET Latin-1 RET
4837chooses the Latin-1 character set. In the .emacs file, you can do this
4838with (set-language-environment "Latin-1").
4839
4840*** The command C-x RET f (set-buffer-file-coding-system)
4841specifies the file coding system for the current buffer. This
4842specifies what sort of character code translation to do when saving
4843the file. As an argument, you must specify the name of one of the
4844coding systems that Emacs supports.
4845
4846*** The command C-x RET c (universal-coding-system-argument)
4847lets you specify a coding system when you read or write a file.
4848This command uses the minibuffer to read a coding system name.
4849After you exit the minibuffer, the specified coding system
4850is used for *the immediately following command*.
4851
4852So if the immediately following command is a command to read or
4853write a file, it uses the specified coding system for that file.
4854
4855If the immediately following command does not use the coding system,
4856then C-x RET c ultimately has no effect.
4857
4858For example, C-x RET c iso-8859-1 RET C-x C-f temp RET
4859visits the file `temp' treating it as ISO Latin-1.
4860
4861*** You can specify the coding system for a file using the -*-
4862construct. Include `coding: CODINGSYSTEM;' inside the -*-...-*-
4863to specify use of coding system CODINGSYSTEM. You can also
4864specify the coding system in a local variable list at the end
4865of the file.
4866
4867*** The command C-x RET t (set-terminal-coding-system) specifies
4868the coding system for terminal output. If you specify a character
4869code for terminal output, all characters output to the terminal are
4870translated into that character code.
4871
4872This feature is useful for certain character-only terminals built in
4873various countries to support the languages of those countries.
4874
4875By default, output to the terminal is not translated at all.
4876
4877*** The command C-x RET k (set-keyboard-coding-system) specifies
4878the coding system for keyboard input.
4879
4880Character code translation of keyboard input is useful for terminals
4881with keys that send non-ASCII graphic characters--for example,
4882some terminals designed for ISO Latin-1 or subsets of it.
4883
4884By default, keyboard input is not translated at all.
4885
4886Character code translation of keyboard input is similar to using an
4887input method, in that both define sequences of keyboard input that
4888translate into single characters. However, input methods are designed
4889to be convenient for interactive use, while the code translations are
4890designed to work with terminals.
4891
4892*** The command C-x RET p (set-buffer-process-coding-system)
4893specifies the coding system for input and output to a subprocess.
4894This command applies to the current buffer; normally, each subprocess
4895has its own buffer, and thus you can use this command to specify
4896translation to and from a particular subprocess by giving the command
4897in the corresponding buffer.
4898
4899By default, process input and output are not translated at all.
4900
4901*** The variable file-name-coding-system specifies the coding system
4902to use for encoding file names before operating on them.
4903It is also used for decoding file names obtained from the system.
4904
4905*** The command C-\ (toggle-input-method) activates or deactivates
4906an input method. If no input method has been selected before, the
4907command prompts for you to specify the language and input method you
4908want to use.
4909
4910C-u C-\ (select-input-method) lets you switch to a different input
4911method. C-h C-\ (or C-h I) describes the current input method.
4912
4913*** Some input methods remap the keyboard to emulate various keyboard
4914layouts commonly used for particular scripts. How to do this
4915remapping properly depends on your actual keyboard layout. To specify
4916which layout your keyboard has, use M-x quail-set-keyboard-layout.
4917
4918*** The command C-h C (describe-coding-system) displays
4919the coding systems currently selected for various purposes, plus
4920related information.
4921
4922*** The command C-h h (view-hello-file) displays a file called
4923HELLO, which has examples of text in many languages, using various
4924scripts.
4925
4926*** The command C-h L (describe-language-support) displays
4927information about the support for a particular language.
4928You specify the language as an argument.
4929
4930*** The mode line now contains a letter or character that identifies
4931the coding system used in the visited file. It normally follows the
4932first dash.
4933
4934A dash indicates the default state of affairs: no code conversion
4935(except CRLF => newline if appropriate). `=' means no conversion
4936whatsoever. The ISO 8859 coding systems are represented by digits
49371 through 9. Other coding systems are represented by letters:
4938
4939 A alternativnyj (Russian)
4940 B big5 (Chinese)
4941 C cn-gb-2312 (Chinese)
4942 C iso-2022-cn (Chinese)
4943 D in-is13194-devanagari (Indian languages)
4944 E euc-japan (Japanese)
4945 I iso-2022-cjk or iso-2022-ss2 (Chinese, Japanese, Korean)
4946 J junet (iso-2022-7) or old-jis (iso-2022-jp-1978-irv) (Japanese)
4947 K euc-korea (Korean)
4948 R koi8 (Russian)
4949 Q tibetan
4950 S shift_jis (Japanese)
4951 T lao
4952 T tis620 (Thai)
4953 V viscii or vscii (Vietnamese)
4954 i iso-2022-lock (Chinese, Japanese, Korean)
4955 k iso-2022-kr (Korean)
4956 v viqr (Vietnamese)
4957 z hz (Chinese)
4958
4959When you are using a character-only terminal (not a window system),
4960two additional characters appear in between the dash and the file
4961coding system. These two characters describe the coding system for
4962keyboard input, and the coding system for terminal output.
4963
4964*** The new variable rmail-file-coding-system specifies the code
4965conversion to use for RMAIL files. The default value is nil.
4966
4967When you read mail with Rmail, each message is decoded automatically
4968into Emacs' internal format. This has nothing to do with
4969rmail-file-coding-system. That variable controls reading and writing
4970Rmail files themselves.
4971
4972*** The new variable sendmail-coding-system specifies the code
4973conversion for outgoing mail. The default value is nil.
4974
4975Actually, there are three different ways of specifying the coding system
4976for sending mail:
4977
4978- If you use C-x RET f in the mail buffer, that takes priority.
4979- Otherwise, if you set sendmail-coding-system non-nil, that specifies it.
4980- Otherwise, the default coding system for new files is used,
4981 if that is non-nil. That comes from your language environment.
4982- Otherwise, Latin-1 is used.
4983
4984*** The command C-h t (help-with-tutorial) accepts a prefix argument
4985to specify the language for the tutorial file. Currently, English,
4986Japanese, Korean and Thai are supported. We welcome additional
4987translations.
4988
4989** An easy new way to visit a file with no code or format conversion
4990of any kind: Use M-x find-file-literally. There is also a command
4991insert-file-literally which inserts a file into the current buffer
4992without any conversion.
4993
4994** C-q's handling of octal character codes is changed.
4995You can now specify any number of octal digits.
4996RET terminates the digits and is discarded;
4997any other non-digit terminates the digits and is then used as input.
4998
4999** There are new commands for looking up Info documentation for
5000functions, variables and file names used in your programs.
5001
5002Type M-x info-lookup-symbol to look up a symbol in the buffer at point.
5003Type M-x info-lookup-file to look up a file in the buffer at point.
5004
5005Precisely which Info files are used to look it up depends on the major
5006mode. For example, in C mode, the GNU libc manual is used.
5007
5008** M-TAB in most programming language modes now runs the command
5009complete-symbol. This command performs completion on the symbol name
5010in the buffer before point.
5011
5012With a numeric argument, it performs completion based on the set of
5013symbols documented in the Info files for the programming language that
5014you are using.
5015
5016With no argument, it does completion based on the current tags tables,
5017just like the old binding of M-TAB (complete-tag).
5018
5019** File locking works with NFS now.
5020
5021The lock file for FILENAME is now a symbolic link named .#FILENAME,
5022in the same directory as FILENAME.
5023
5024This means that collision detection between two different machines now
5025works reasonably well; it also means that no file server or directory
5026can become a bottleneck.
5027
5028The new method does have drawbacks. It means that collision detection
5029does not operate when you edit a file in a directory where you cannot
5030create new files. Collision detection also doesn't operate when the
5031file server does not support symbolic links. But these conditions are
5032rare, and the ability to have collision detection while using NFS is
5033so useful that the change is worth while.
5034
5035When Emacs or a system crashes, this may leave behind lock files which
5036are stale. So you may occasionally get warnings about spurious
5037collisions. When you determine that the collision is spurious, just
5038tell Emacs to go ahead anyway.
5039
5040** If you wish to use Show Paren mode to display matching parentheses,
5041it is no longer sufficient to load paren.el. Instead you must call
5042show-paren-mode.
5043
5044** If you wish to use Delete Selection mode to replace a highlighted
5045selection when you insert new text, it is no longer sufficient to load
5046delsel.el. Instead you must call the function delete-selection-mode.
5047
5048** If you wish to use Partial Completion mode to complete partial words
5049within symbols or filenames, it is no longer sufficient to load
5050complete.el. Instead you must call the function partial-completion-mode.
5051
5052** If you wish to use uniquify to rename buffers for you,
5053it is no longer sufficient to load uniquify.el. You must also
5054set uniquify-buffer-name-style to one of the non-nil legitimate values.
5055
5056** Changes in View mode.
5057
5058*** Several new commands are available in View mode.
5059Do H in view mode for a list of commands.
5060
5061*** There are two new commands for entering View mode:
5062view-file-other-frame and view-buffer-other-frame.
5063
5064*** Exiting View mode does a better job of restoring windows to their
5065previous state.
5066
5067*** New customization variable view-scroll-auto-exit. If non-nil,
5068scrolling past end of buffer makes view mode exit.
5069
5070*** New customization variable view-exits-all-viewing-windows. If
5071non-nil, view-mode will at exit restore all windows viewing buffer,
5072not just the selected window.
5073
5074*** New customization variable view-read-only. If non-nil, visiting a
5075read-only file automatically enters View mode, and toggle-read-only
5076turns View mode on or off.
5077
5078*** New customization variable view-remove-frame-by-deleting controls
5079how to remove a not needed frame at view mode exit. If non-nil,
5080delete the frame, if nil make an icon of it.
5081
5082** C-x v l, the command to print a file's version control log,
5083now positions point at the entry for the file's current branch version.
5084
5085** C-x v =, the command to compare a file with the last checked-in version,
5086has a new feature. If the file is currently not locked, so that it is
5087presumably identical to the last checked-in version, the command now asks
5088which version to compare with.
5089
5090** When using hideshow.el, incremental search can temporarily show hidden
79214ddf 5091blocks if a match is inside the block.
a933dad1
DL
5092
5093The block is hidden again if the search is continued and the next match
5094is outside the block. By customizing the variable
5095isearch-hide-immediately you can choose to hide all the temporarily
5096shown blocks only when exiting from incremental search.
5097
5098By customizing the variable hs-isearch-open you can choose what kind
5099of blocks to temporarily show during isearch: comment blocks, code
5100blocks, all of them or none.
5101
5102** The new command C-x 4 0 (kill-buffer-and-window) kills the
5103current buffer and deletes the selected window. It asks for
5104confirmation first.
5105
5106** C-x C-w, which saves the buffer into a specified file name,
5107now changes the major mode according to that file name.
5108However, the mode will not be changed if
5109(1) a local variables list or the `-*-' line specifies a major mode, or
5110(2) the current major mode is a "special" mode,
5111 not suitable for ordinary files, or
5112(3) the new file name does not particularly specify any mode.
5113
5114This applies to M-x set-visited-file-name as well.
5115
5116However, if you set change-major-mode-with-file-name to nil, then
5117these commands do not change the major mode.
5118
5119** M-x occur changes.
5120
5121*** If the argument to M-x occur contains upper case letters,
5122it performs a case-sensitive search.
5123
5124*** In the *Occur* buffer made by M-x occur,
5125if you type g or M-x revert-buffer, this repeats the search
5126using the same regular expression and the same buffer as before.
5127
5128** In Transient Mark mode, the region in any one buffer is highlighted
5129in just one window at a time. At first, it is highlighted in the
5130window where you set the mark. The buffer's highlighting remains in
5131that window unless you select to another window which shows the same
5132buffer--then the highlighting moves to that window.
5133
5134** The feature to suggest key bindings when you use M-x now operates
5135after the command finishes. The message suggesting key bindings
5136appears temporarily in the echo area. The previous echo area contents
5137come back after a few seconds, in case they contain useful information.
5138
5139** Each frame now independently records the order for recently
5140selected buffers, so that the default for C-x b is now based on the
5141buffers recently selected in the selected frame.
5142
5143** Outline mode changes.
5144
5145*** Outline mode now uses overlays (this is the former noutline.el).
5146
5147*** Incremental searches skip over invisible text in Outline mode.
5148
5149** When a minibuffer window is active but not the selected window, if
5150you try to use the minibuffer, you used to get a nested minibuffer.
5151Now, this not only gives an error, it also cancels the minibuffer that
5152was already active.
5153
5154The motive for this change is so that beginning users do not
5155unknowingly move away from minibuffers, leaving them active, and then
5156get confused by it.
5157
5158If you want to be able to have recursive minibuffers, you must
5159set enable-recursive-minibuffers to non-nil.
5160
5161** Changes in dynamic abbrevs.
5162
5163*** Expanding dynamic abbrevs with M-/ is now smarter about case
5164conversion. If the expansion has mixed case not counting the first
5165character, and the abbreviation matches the beginning of the expansion
5166including case, then the expansion is copied verbatim.
5167
5168The expansion is also copied verbatim if the abbreviation itself has
5169mixed case. And using SPC M-/ to copy an additional word always
5170copies it verbatim except when the previous copied word is all caps.
5171
5172*** The values of `dabbrev-case-replace' and `dabbrev-case-fold-search'
5173are no longer Lisp expressions. They have simply three possible
5174values.
5175
5176`dabbrev-case-replace' has these three values: nil (don't preserve
5177case), t (do), or `case-replace' (do like M-x query-replace).
5178`dabbrev-case-fold-search' has these three values: nil (don't ignore
5179case), t (do), or `case-fold-search' (do like search).
5180
5181** Minibuffer history lists are truncated automatically now to a
5182certain length. The variable history-length specifies how long they
5183can be. The default value is 30.
5184
5185** Changes in Mail mode.
5186
5187*** The key C-x m no longer runs the `mail' command directly.
5188Instead, it runs the command `compose-mail', which invokes the mail
5189composition mechanism you have selected with the variable
5190`mail-user-agent'. The default choice of user agent is
5191`sendmail-user-agent', which gives behavior compatible with the old
5192behavior.
5193
5194C-x 4 m now runs compose-mail-other-window, and C-x 5 m runs
5195compose-mail-other-frame.
5196
5197*** While composing a reply to a mail message, from Rmail, you can use
5198the command C-c C-r to cite just the region from the message you are
5199replying to. This copies the text which is the selected region in the
5200buffer that shows the original message.
5201
5202*** The command C-c C-i inserts a file at the end of the message,
5203with separator lines around the contents.
5204
5205*** The command M-x expand-mail-aliases expands all mail aliases
5206in suitable mail headers. Emacs automatically extracts mail alias
5207definitions from your mail alias file (e.g., ~/.mailrc). You do not
5208need to expand mail aliases yourself before sending mail.
5209
5210*** New features in the mail-complete command.
5211
5212**** The mail-complete command now inserts the user's full name,
5213for local users or if that is known. The variable mail-complete-style
5214controls the style to use, and whether to do this at all.
5215Its values are like those of mail-from-style.
5216
5217**** The variable mail-passwd-command lets you specify a shell command
5218to run to fetch a set of password-entries that add to the ones in
5219/etc/passwd.
5220
5221**** The variable mail-passwd-file now specifies a list of files to read
5222to get the list of user ids. By default, one file is used:
5223/etc/passwd.
5224
5225** You can "quote" a file name to inhibit special significance of
5226special syntax, by adding `/:' to the beginning. Thus, if you have a
5227directory named `/foo:', you can prevent it from being treated as a
5228reference to a remote host named `foo' by writing it as `/:/foo:'.
5229
5230Emacs uses this new construct automatically when necessary, such as
5231when you start it with a working directory whose name might otherwise
5232be taken to be magic.
5233
5234** There is a new command M-x grep-find which uses find to select
5235files to search through, and grep to scan them. The output is
5236available in a Compile mode buffer, as with M-x grep.
5237
5238M-x grep now uses the -e option if the grep program supports that.
5239(-e prevents problems if the search pattern starts with a dash.)
5240
5241** In Dired, the & command now flags for deletion the files whose names
5242suggest they are probably not needed in the long run.
5243
5244In Dired, * is now a prefix key for mark-related commands.
5245
5246new key dired.el binding old key
5247------- ---------------- -------
5248 * c dired-change-marks c
5249 * m dired-mark m
5250 * * dired-mark-executables * (binding deleted)
5251 * / dired-mark-directories / (binding deleted)
5252 * @ dired-mark-symlinks @ (binding deleted)
5253 * u dired-unmark u
5254 * DEL dired-unmark-backward DEL
5255 * ? dired-unmark-all-files M-C-?
5256 * ! dired-unmark-all-marks
5257 * % dired-mark-files-regexp % m
5258 * C-n dired-next-marked-file M-}
5259 * C-p dired-prev-marked-file M-{
5260
5261** Rmail changes.
5262
5263*** When Rmail cannot convert your incoming mail into Babyl format, it
5264saves the new mail in the file RMAILOSE.n, where n is an integer
5265chosen to make a unique name. This way, Rmail will not keep crashing
5266each time you run it.
5267
5268*** In Rmail, the variable rmail-summary-line-count-flag now controls
5269whether to include the line count in the summary. Non-nil means yes.
5270
5271*** In Rmail summary buffers, d and C-d (the commands to delete
5272messages) now take repeat counts as arguments. A negative argument
5273means to move in the opposite direction.
5274
5275*** In Rmail, the t command now takes an optional argument which lets
5276you specify whether to show the message headers in full or pruned.
5277
5278*** In Rmail, the new command w (rmail-output-body-to-file) writes
5279just the body of the current message into a file, without the headers.
5280It takes the file name from the message subject, by default, but you
5281can edit that file name in the minibuffer before it is actually used
5282for output.
5283
5284** Gnus changes.
5285
5286*** nntp.el has been totally rewritten in an asynchronous fashion.
5287
79214ddf
FP
5288*** Article prefetching functionality has been moved up into
5289Gnus.
a933dad1 5290
79214ddf 5291*** Scoring can now be performed with logical operators like
a933dad1
DL
5292`and', `or', `not', and parent redirection.
5293
5294*** Article washing status can be displayed in the
5295article mode line.
5296
5297*** gnus.el has been split into many smaller files.
5298
5299*** Suppression of duplicate articles based on Message-ID.
5300
5301(setq gnus-suppress-duplicates t)
5302
5303*** New variables for specifying what score and adapt files
5304are to be considered home score and adapt files. See
5305`gnus-home-score-file' and `gnus-home-adapt-files'.
5306
5307*** Groups can inherit group parameters from parent topics.
5308
5309*** Article editing has been revamped and is now usable.
5310
5311*** Signatures can be recognized in more intelligent fashions.
5312See `gnus-signature-separator' and `gnus-signature-limit'.
5313
5314*** Summary pick mode has been made to look more nn-like.
5315Line numbers are displayed and the `.' command can be
5316used to pick articles.
5317
5318*** Commands for moving the .newsrc.eld from one server to
5319another have been added.
5320
5321 `M-x gnus-change-server'
5322
5323*** A way to specify that "uninteresting" fields be suppressed when
5324generating lines in buffers.
5325
5326*** Several commands in the group buffer can be undone with
5327`M-C-_'.
5328
5329*** Scoring can be done on words using the new score type `w'.
5330
5331*** Adaptive scoring can be done on a Subject word-by-word basis:
5332
5333 (setq gnus-use-adaptive-scoring '(word))
5334
5335*** Scores can be decayed.
79214ddf 5336
a933dad1
DL
5337 (setq gnus-decay-scores t)
5338
5339*** Scoring can be performed using a regexp on the Date header. The
5340Date is normalized to compact ISO 8601 format first.
5341
5342*** A new command has been added to remove all data on articles from
5343the native server.
5344
5345 `M-x gnus-group-clear-data-on-native-groups'
5346
5347*** A new command for reading collections of documents
5348(nndoc with nnvirtual on top) has been added -- `M-C-d'.
5349
5350*** Process mark sets can be pushed and popped.
5351
5352*** A new mail-to-news backend makes it possible to post
5353even when the NNTP server doesn't allow posting.
5354
5355*** A new backend for reading searches from Web search engines
5356(DejaNews, Alta Vista, InReference) has been added.
5357
5358 Use the `G w' command in the group buffer to create such
5359 a group.
5360
5361*** Groups inside topics can now be sorted using the standard
5362sorting functions, and each topic can be sorted independently.
5363
5364 See the commands under the `T S' submap.
5365
5366*** Subsets of the groups can be sorted independently.
5367
5368 See the commands under the `G P' submap.
5369
5370*** Cached articles can be pulled into the groups.
79214ddf 5371
a933dad1
DL
5372 Use the `Y c' command.
5373
5374*** Score files are now applied in a more reliable order.
5375
5376*** Reports on where mail messages end up can be generated.
5377
5378 `M-x nnmail-split-history'
5379
5380*** More hooks and functions have been added to remove junk
5381from incoming mail before saving the mail.
79214ddf 5382
a933dad1
DL
5383 See `nnmail-prepare-incoming-header-hook'.
5384
5385*** The nnml mail backend now understands compressed article files.
5386
5387*** To enable Gnus to read/post multi-lingual articles, you must execute
5388the following code, for instance, in your .emacs.
5389
5390 (add-hook 'gnus-startup-hook 'gnus-mule-initialize)
5391
5392Then, when you start Gnus, it will decode non-ASCII text automatically
5393and show appropriate characters. (Note: if you are using gnus-mime
5394from the SEMI package, formerly known as TM, you should NOT add this
5395hook to gnus-startup-hook; gnus-mime has its own method of handling
5396this issue.)
5397
5398Since it is impossible to distinguish all coding systems
5399automatically, you may need to specify a choice of coding system for a
5400particular news group. This can be done by:
5401
5402 (gnus-mule-add-group NEWSGROUP 'CODING-SYSTEM)
5403
5404Here NEWSGROUP should be a string which names a newsgroup or a tree
5405of newsgroups. If NEWSGROUP is "XXX.YYY", all news groups under
5406"XXX.YYY" (including "XXX.YYY.ZZZ") will use the specified coding
5407system. CODING-SYSTEM specifies which coding system to use (for both
5408for reading and posting).
5409
5410CODING-SYSTEM can also be a cons cell of the form
5411 (READ-CODING-SYSTEM . POST-CODING-SYSTEM)
5412Then READ-CODING-SYSTEM is used when you read messages from the
5413newsgroups, while POST-CODING-SYSTEM is used when you post messages
5414there.
5415
5416Emacs knows the right coding systems for certain newsgroups by
5417default. Here are some of these default settings:
5418
5419 (gnus-mule-add-group "fj" 'iso-2022-7)
5420 (gnus-mule-add-group "alt.chinese.text" 'hz-gb-2312)
5421 (gnus-mule-add-group "alt.hk" 'hz-gb-2312)
5422 (gnus-mule-add-group "alt.chinese.text.big5" 'cn-big5)
5423 (gnus-mule-add-group "soc.culture.vietnamese" '(nil . viqr))
5424
5425When you reply by mail to an article, these settings are ignored;
5426the mail is encoded according to sendmail-coding-system, as usual.
5427
5428** CC mode changes.
5429
5430*** If you edit primarily one style of C (or C++, Objective-C, Java)
5431code, you may want to make the CC Mode style variables have global
5432values so that you can set them directly in your .emacs file. To do
5433this, set c-style-variables-are-local-p to nil in your .emacs file.
5434Note that this only takes effect if you do it *before* cc-mode.el is
5435loaded.
5436
5437If you typically edit more than one style of C (or C++, Objective-C,
79214ddf 5438Java) code in a single Emacs session, you may want to make the CC Mode
a933dad1 5439style variables have buffer local values. By default, all buffers
79214ddf
FP
5440share the same style variable settings; to make them buffer local, set
5441c-style-variables-are-local-p to t in your .emacs file. Note that you
a933dad1
DL
5442must do this *before* CC Mode is loaded.
5443
5444*** The new variable c-indentation-style holds the C style name
5445of the current buffer.
5446
5447*** The variable c-block-comments-indent-p has been deleted, because
5448it is no longer necessary. C mode now handles all the supported styles
5449of block comments, with no need to say which one you will use.
5450
5451*** There is a new indentation style "python", which specifies the C
5452style that the Python developers like.
5453
5454*** There is a new c-cleanup-list option: brace-elseif-brace.
5455This says to put ...} else if (...) {... on one line,
5456just as brace-else-brace says to put ...} else {... on one line.
5457
5458** VC Changes [new]
5459
5460** In vc-retrieve-snapshot (C-x v r), if you don't specify a snapshot
5461name, it retrieves the *latest* versions of all files in the current
5462directory and its subdirectories (aside from files already locked).
5463
5464This feature is useful if your RCS directory is a link to a common
5465master directory, and you want to pick up changes made by other
5466developers.
5467
5468You can do the same thing for an individual file by typing C-u C-x C-q
5469RET in a buffer visiting that file.
5470
5471*** VC can now handle files under CVS that are being "watched" by
5472other developers. Such files are made read-only by CVS. To get a
5473writable copy, type C-x C-q in a buffer visiting such a file. VC then
5474calls "cvs edit", which notifies the other developers of it.
5475
5476*** vc-version-diff (C-u C-x v =) now suggests reasonable defaults for
5477version numbers, based on the current state of the file.
5478
5479** Calendar changes.
5480
5481A new function, list-holidays, allows you list holidays or subclasses
5482of holidays for ranges of years. Related menu items allow you do this
5483for the year of the selected date, or the following/previous years.
5484
5485** ps-print changes
5486
79214ddf 5487There are some new user variables for customizing the page layout.
a933dad1
DL
5488
5489*** Paper size, paper orientation, columns
5490
5491The variable `ps-paper-type' determines the size of paper ps-print
5492formats for; it should contain one of the symbols:
5493`a4' `a3' `letter' `legal' `letter-small' `tabloid'
5494`ledger' `statement' `executive' `a4small' `b4' `b5'
5495It defaults to `letter'.
5496If you need other sizes, see the variable `ps-page-dimensions-database'.
5497
5498The variable `ps-landscape-mode' determines the orientation
79214ddf 5499of the printing on the page. nil, the default, means "portrait" mode,
a933dad1
DL
5500non-nil means "landscape" mode.
5501
5502The variable `ps-number-of-columns' must be a positive integer.
5503It determines the number of columns both in landscape and portrait mode.
79214ddf 5504It defaults to 1.
a933dad1
DL
5505
5506*** Horizontal layout
5507
5508The horizontal layout is determined by the variables
5509`ps-left-margin', `ps-inter-column', and `ps-right-margin'.
5510All are measured in points.
5511
5512*** Vertical layout
5513
5514The vertical layout is determined by the variables
5515`ps-bottom-margin', `ps-top-margin', and `ps-header-offset'.
5516All are measured in points.
5517
5518*** Headers
5519
5520If the variable `ps-print-header' is nil, no header is printed. Then
5521`ps-header-offset' is not relevant and `ps-top-margin' represents the
5522margin above the text.
5523
79214ddf 5524If the variable `ps-print-header-frame' is non-nil, a gaudy
a933dad1
DL
5525framing box is printed around the header.
5526
5527The contents of the header are determined by `ps-header-lines',
5528`ps-show-n-of-n', `ps-left-header' and `ps-right-header'.
5529
79214ddf
FP
5530The height of the header is determined by `ps-header-line-pad',
5531`ps-header-font-family', `ps-header-title-font-size' and
a933dad1
DL
5532`ps-header-font-size'.
5533
5534*** Font managing
5535
5536The variable `ps-font-family' determines which font family is to be
5537used for ordinary text. Its value must be a key symbol in the alist
5538`ps-font-info-database'. You can add other font families by adding
5539elements to this alist.
5540
79214ddf 5541The variable `ps-font-size' determines the size of the font
a933dad1
DL
5542for ordinary text. It defaults to 8.5 points.
5543
5544** hideshow changes.
5545
5546*** now supports hiding of blocks of single line comments (like // for
79214ddf 5547C++, ; for lisp).
a933dad1
DL
5548
5549*** Support for java-mode added.
5550
5551*** When doing `hs-hide-all' it is now possible to also hide the comments
5552in the file if `hs-hide-comments-when-hiding-all' is set.
5553
5554*** The new function `hs-hide-initial-comment' hides the the comments at
5555the beginning of the files. Finally those huge RCS logs don't stay in your
5556way! This is run by default when entering the `hs-minor-mode'.
5557
5558*** Now uses overlays instead of `selective-display', so is more
5559robust and a lot faster.
5560
79214ddf 5561*** A block beginning can span multiple lines.
a933dad1
DL
5562
5563*** The new variable `hs-show-hidden-short-form' if t, directs hideshow
5564to show only the beginning of a block when it is hidden. See the
5565documentation for more details.
5566
5567** Changes in Enriched mode.
5568
5569*** When you visit a file in enriched-mode, Emacs will make sure it is
5570filled to the current fill-column. This behavior is now independent
5571of the size of the window. When you save the file, the fill-column in
5572use is stored as well, so that the whole buffer need not be refilled
5573the next time unless the fill-column is different.
5574
5575*** use-hard-newlines is now a minor mode. When it is enabled, Emacs
5576distinguishes between hard and soft newlines, and treats hard newlines
5577as paragraph boundaries. Otherwise all newlines inserted are marked
5578as soft, and paragraph boundaries are determined solely from the text.
5579
5580** Font Lock mode
5581
5582*** Custom support
5583
5584The variables font-lock-face-attributes, font-lock-display-type and
5585font-lock-background-mode are now obsolete; the recommended way to specify the
5586faces to use for Font Lock mode is with M-x customize-group on the new custom
5587group font-lock-highlighting-faces. If you set font-lock-face-attributes in
5588your ~/.emacs file, Font Lock mode will respect its value. However, you should
5589consider converting from setting that variable to using M-x customize.
5590
5591You can still use X resources to specify Font Lock face appearances.
5592
5593*** Maximum decoration
5594
5595Fontification now uses the maximum level of decoration supported by
5596default. Previously, fontification used a mode-specific default level
5597of decoration, which is typically the minimum level of decoration
5598supported. You can set font-lock-maximum-decoration to nil
5599to get the old behavior.
5600
5601*** New support
5602
5603Support is now provided for Java, Objective-C, AWK and SIMULA modes.
5604
5605Note that Font Lock mode can be turned on without knowing exactly what modes
5606support Font Lock mode, via the command global-font-lock-mode.
5607
5608*** Configurable support
5609
5610Support for C, C++, Objective-C and Java can be more easily configured for
5611additional types and classes via the new variables c-font-lock-extra-types,
5612c++-font-lock-extra-types, objc-font-lock-extra-types and, you guessed it,
5613java-font-lock-extra-types. These value of each of these variables should be a
5614list of regexps matching the extra type names. For example, the default value
5615of c-font-lock-extra-types is ("\\sw+_t") which means fontification follows the
5616convention that C type names end in _t. This results in slower fontification.
5617
5618Of course, you can change the variables that specify fontification in whatever
5619way you wish, typically by adding regexps. However, these new variables make
5620it easier to make specific and common changes for the fontification of types.
5621
5622*** Adding highlighting patterns to existing support
5623
5624You can use the new function font-lock-add-keywords to add your own
5625highlighting patterns, such as for project-local or user-specific constructs,
5626for any mode.
5627
5628For example, to highlight `FIXME:' words in C comments, put:
5629
5630 (font-lock-add-keywords 'c-mode '(("\\<FIXME:" 0 font-lock-warning-face t)))
5631
5632in your ~/.emacs.
5633
5634*** New faces
5635
5636Font Lock now defines two new faces, font-lock-builtin-face and
5637font-lock-warning-face. These are intended to highlight builtin keywords,
5638distinct from a language's normal keywords, and objects that should be brought
5639to user attention, respectively. Various modes now use these new faces.
5640
5641*** Changes to fast-lock support mode
5642
5643The fast-lock package, one of the two Font Lock support modes, can now process
5644cache files silently. You can use the new variable fast-lock-verbose, in the
5645same way as font-lock-verbose, to control this feature.
5646
5647*** Changes to lazy-lock support mode
5648
5649The lazy-lock package, one of the two Font Lock support modes, can now fontify
5650according to the true syntactic context relative to other lines. You can use
5651the new variable lazy-lock-defer-contextually to control this feature. If
5652non-nil, changes to the buffer will cause subsequent lines in the buffer to be
5653refontified after lazy-lock-defer-time seconds of idle time. If nil, then only
5654the modified lines will be refontified; this is the same as the previous Lazy
5655Lock mode behaviour and the behaviour of Font Lock mode.
5656
5657This feature is useful in modes where strings or comments can span lines.
5658For example, if a string or comment terminating character is deleted, then if
5659this feature is enabled subsequent lines in the buffer will be correctly
5660refontified to reflect their new syntactic context. Previously, only the line
5661containing the deleted character would be refontified and you would have to use
5662the command M-g M-g (font-lock-fontify-block) to refontify some lines.
5663
5664As a consequence of this new feature, two other variables have changed:
5665
5666Variable `lazy-lock-defer-driven' is renamed `lazy-lock-defer-on-scrolling'.
5667Variable `lazy-lock-defer-time' can now only be a time, i.e., a number.
5668Buffer modes for which on-the-fly deferral applies can be specified via the
5669new variable `lazy-lock-defer-on-the-fly'.
5670
5671If you set these variables in your ~/.emacs, then you may have to change those
5672settings.
5673
5674** Ada mode changes.
5675
5676*** There is now better support for using find-file.el with Ada mode.
5677If you switch between spec and body, the cursor stays in the same
5678procedure (modulo overloading). If a spec has no body file yet, but
5679you try to switch to its body file, Ada mode now generates procedure
5680stubs.
5681
5682*** There are two new commands:
5683 - `ada-make-local' : invokes gnatmake on the current buffer
5684 - `ada-check-syntax' : check syntax of current buffer.
5685
5686The user options `ada-compiler-make', `ada-make-options',
5687`ada-language-version', `ada-compiler-syntax-check', and
79214ddf 5688`ada-compile-options' are used within these commands.
a933dad1
DL
5689
5690*** Ada mode can now work with Outline minor mode. The outline level
5691is calculated from the indenting, not from syntactic constructs.
5692Outlining does not work if your code is not correctly indented.
5693
5694*** The new function `ada-gnat-style' converts the buffer to the style of
5695formatting used in GNAT. It places two blanks after a comment start,
5696places one blank between a word end and an opening '(', and puts one
5697space between a comma and the beginning of a word.
5698
5699** Scheme mode changes.
5700
5701*** Scheme mode indentation now uses many of the facilities of Lisp
5702mode; therefore, the variables to customize it are the variables used
5703for Lisp mode which have names starting with `lisp-'. The variables
5704with names starting with `scheme-' which used to do this no longer
5705have any effect.
5706
5707If you want to use different indentation for Scheme and Lisp, this is
5708still possible, but now you must do it by adding a hook to
5709scheme-mode-hook, which could work by setting the `lisp-' indentation
5710variables as buffer-local variables.
5711
5712*** DSSSL mode is a variant of Scheme mode, for editing DSSSL scripts.
5713Use M-x dsssl-mode.
5714
133c9e59
GM
5715** Changes to the emacsclient program
5716
875c1439
GM
5717*** If a socket can't be found, and environment variables LOGNAME or
5718USER are set, emacsclient now looks for a socket based on the UID
5719associated with the name. That is an emacsclient running as root
5720can connect to an Emacs server started by a non-root user.
5721
133c9e59 5722*** The emacsclient program now accepts an option --no-wait which tells
a933dad1
DL
5723it to return immediately without waiting for you to "finish" the
5724buffer in Emacs.
5725
133c9e59
GM
5726*** The new option --alternate-editor allows to specify an editor to
5727use if Emacs is not running. The environment variable
5728ALTERNATE_EDITOR can be used for the same effect; the command line
5729option takes precedence.
5730
a933dad1
DL
5731** M-x eldoc-mode enables a minor mode in which the echo area
5732constantly shows the parameter list for function being called at point
5733(in Emacs Lisp and Lisp Interaction modes only).
5734
5735** C-x n d now runs the new command narrow-to-defun,
5736which narrows the accessible parts of the buffer to just
5737the current defun.
5738
5739** Emacs now handles the `--' argument in the standard way; all
5740following arguments are treated as ordinary file names.
5741
5742** On MSDOS and Windows, the bookmark file is now called _emacs.bmk,
5743and the saved desktop file is now called _emacs.desktop (truncated if
5744necessary).
5745
5746** When you kill a buffer that visits a file,
5747if there are any registers that save positions in the file,
5748these register values no longer become completely useless.
5749If you try to go to such a register with C-x j, then you are
5750asked whether to visit the file again. If you say yes,
5751it visits the file and then goes to the same position.
5752
5753** When you visit a file that changes frequently outside Emacs--for
5754example, a log of output from a process that continues to run--it may
5755be useful for Emacs to revert the file without querying you whenever
5756you visit the file afresh with C-x C-f.
5757
5758You can request this behavior for certain files by setting the
5759variable revert-without-query to a list of regular expressions. If a
5760file's name matches any of these regular expressions, find-file and
5761revert-buffer revert the buffer without asking for permission--but
5762only if you have not edited the buffer text yourself.
5763
5764** set-default-font has been renamed to set-frame-font
5765since it applies only to the current frame.
5766
5767** In TeX mode, you can use the variable tex-main-file to specify the
5768file for tex-file to run TeX on. (By default, tex-main-file is nil,
5769and tex-file runs TeX on the current visited file.)
5770
5771This is useful when you are editing a document that consists of
5772multiple files. In each of the included files, you can set up a local
5773variable list which specifies the top-level file of your document for
5774tex-main-file. Then tex-file will run TeX on the whole document
5775instead of just the file you are editing.
5776
5777** RefTeX mode
5778
5779RefTeX mode is a new minor mode with special support for \label, \ref
5780and \cite macros in LaTeX documents. RefTeX distinguishes labels of
5781different environments (equation, figure, ...) and has full support for
5782multifile documents. To use it, select a buffer with a LaTeX document and
5783turn the mode on with M-x reftex-mode. Here are the main user commands:
5784
79214ddf 5785C-c ( reftex-label
a933dad1
DL
5786 Creates a label semi-automatically. RefTeX is context sensitive and
5787 knows which kind of label is needed.
5788
5789C-c ) reftex-reference
5790 Offers in a menu all labels in the document, along with context of the
5791 label definition. The selected label is referenced as \ref{LABEL}.
5792
5793C-c [ reftex-citation
5794 Prompts for a regular expression and displays a list of matching BibTeX
5795 database entries. The selected entry is cited with a \cite{KEY} macro.
5796
5797C-c & reftex-view-crossref
5798 Views the cross reference of a \ref or \cite command near point.
5799
5800C-c = reftex-toc
5801 Shows a table of contents of the (multifile) document. From there you
5802 can quickly jump to every section.
79214ddf 5803
a933dad1
DL
5804Under X, RefTeX installs a "Ref" menu in the menu bar, with additional
5805commands. Press `?' to get help when a prompt mentions this feature.
5806Full documentation and customization examples are in the file
5807reftex.el. You can use the finder to view the file documentation:
5808C-h p --> tex --> reftex.el
5809
5810** Changes in BibTeX mode.
5811
5812*** Info documentation is now available.
5813
5814*** Don't allow parentheses in string constants anymore. This confused
5815both the BibTeX program and Emacs BibTeX mode.
5816
5817*** Renamed variable bibtex-mode-user-optional-fields to
5818bibtex-user-optional-fields.
5819
5820*** Removed variable bibtex-include-OPTannote
5821(use bibtex-user-optional-fields instead).
5822
5823*** New interactive functions to copy and kill fields and complete
5824entries to the BibTeX kill ring, from where they can be yanked back by
5825appropriate functions.
5826
5827*** New interactive functions for repositioning and marking of
5828entries. They are bound by default to M-C-l and M-C-h.
5829
5830*** New hook bibtex-clean-entry-hook. It is called after entry has
5831been cleaned.
5832
5833*** New variable bibtex-field-delimiters, which replaces variables
5834bibtex-field-{left|right}-delimiter.
5835
5836*** New variable bibtex-entry-delimiters to determine how entries
5837shall be delimited.
5838
5839*** Allow preinitialization of fields. See documentation of
5840bibtex-user-optional-fields, bibtex-entry-field-alist, and
5841bibtex-include-OPTkey for details.
5842
5843*** Book and InBook entries require either an author or an editor
5844field. This is now supported by bibtex.el. Alternative fields are
5845prefixed with `ALT'.
5846
5847*** New variable bibtex-entry-format, which replaces variable
5848bibtex-clean-entry-zap-empty-opts and allows specification of many
5849formatting options performed on cleaning an entry (see variable
5850documentation).
5851
5852*** Even more control on how automatic keys are generated. See
5853documentation of bibtex-generate-autokey for details. Transcriptions
5854for foreign languages other than German are now handled, too.
5855
5856*** New boolean user option bibtex-comma-after-last-field to decide if
5857comma should be inserted at end of last field.
5858
5859*** New boolean user option bibtex-align-at-equal-sign to determine if
5860alignment should be made at left side of field contents or at equal
5861signs. New user options to control entry layout (e.g. indentation).
5862
5863*** New function bibtex-fill-entry to realign entries.
5864
5865*** New function bibtex-reformat to reformat region or buffer.
5866
5867*** New function bibtex-convert-alien to convert a BibTeX database
5868from alien sources.
5869
5870*** New function bibtex-complete-key (similar to bibtex-complete-string)
5871to complete prefix to a key defined in buffer. Mainly useful in
5872crossref entries.
5873
5874*** New function bibtex-count-entries to count entries in buffer or
5875region.
5876
5877*** Added support for imenu.
5878
5879*** The function `bibtex-validate' now checks current region instead
5880of buffer if mark is active. Now it shows all errors of buffer in a
5881`compilation mode' buffer. You can use the normal commands (e.g.
5882`next-error') for compilation modes to jump to errors.
5883
5884*** New variable `bibtex-string-file-path' to determine where the files
5885from `bibtex-string-files' are searched.
5886
5887** Iso Accents mode now supports Latin-3 as an alternative.
5888
30a009a5 5889** The command next-error now opens blocks hidden by hideshow.
047f434a 5890
a933dad1
DL
5891** The function using-unix-filesystems has been replaced by the
5892functions add-untranslated-filesystem and remove-untranslated-filesystem.
5893Each of these functions takes the name of a drive letter or directory
5894as an argument.
5895
5896When a filesystem is added as untranslated, all files on it are read
5897and written in binary mode (no cr/lf translation is performed).
5898
5899** browse-url changes
5900
5901*** New methods for: Grail (browse-url-generic), MMM (browse-url-mmm),
5902Lynx in a separate xterm (browse-url-lynx-xterm) or in an Emacs window
5903(browse-url-lynx-emacs), remote W3 (browse-url-w3-gnudoit), generic
5904non-remote-controlled browsers (browse-url-generic) and associated
5905customization variables.
5906
5907*** New commands `browse-url-of-region' and `browse-url'.
5908
5909*** URLs marked up with <URL:...> (RFC1738) work if broken across
5910lines. Browsing methods can be associated with URL regexps
5911(e.g. mailto: URLs) via `browse-url-browser-function'.
5912
5913** Changes in Ediff
5914
5915*** Clicking Mouse-2 on a brief command description in Ediff control panel
5916pops up the Info file for this command.
5917
5918*** There is now a variable, ediff-autostore-merges, which controls whether
5919the result of a merge is saved in a file. By default, this is done only when
5920merge is done from a session group (eg, when merging files in two different
5921directories).
5922
5923*** Since Emacs 19.31 (this hasn't been announced before), Ediff can compare
5924and merge groups of files residing in different directories, or revisions of
5925files in the same directory.
5926
5927*** Since Emacs 19.31, Ediff can apply multi-file patches interactively.
5928The patches must be in the context format or GNU unified format. (The bug
5929related to the GNU format has now been fixed.)
5930
5931** Changes in Viper
5932
5933*** The startup file is now .viper instead of .vip
79214ddf 5934*** All variable/function names have been changed to start with viper-
a933dad1
DL
5935 instead of vip-.
5936*** C-\ now simulates the meta-key in all Viper states.
79214ddf 5937*** C-z in Insert state now escapes to Vi for the duration of the next
a933dad1
DL
5938Viper command. In Vi and Insert states, C-z behaves as before.
5939*** C-c \ escapes to Vi for one command if Viper is in Insert or Emacs states.
5940*** _ is no longer the meta-key in Vi state.
5941*** The variable viper-insert-state-cursor-color can be used to change cursor
5942color when Viper is in insert state.
5943*** If search lands the cursor near the top or the bottom of the window,
5944Viper pulls the window up or down to expose more context. The variable
5945viper-adjust-window-after-search controls this behavior.
5946
5947** Etags changes.
5948
5949*** In C, C++, Objective C and Java, Etags tags global variables by
5950default. The resulting tags files are inflated by 30% on average.
5951Use --no-globals to turn this feature off. Etags can also tag
5952variables which are members of structure-like constructs, but it does
5953not by default. Use --members to turn this feature on.
5954
5955*** C++ member functions are now recognized as tags.
5956
5957*** Java is tagged like C++. In addition, "extends" and "implements"
5958constructs are tagged. Files are recognised by the extension .java.
5959
5960*** Etags can now handle programs written in Postscript. Files are
5961recognised by the extensions .ps and .pdb (Postscript with C syntax).
5962In Postscript, tags are lines that start with a slash.
5963
5964*** Etags now handles Objective C and Objective C++ code. The usual C and
5965C++ tags are recognized in these languages; in addition, etags
5966recognizes special Objective C syntax for classes, class categories,
5967methods and protocols.
5968
5969*** Etags also handles Cobol. Files are recognised by the extension
5970.cobol. The tagged lines are those containing a word that begins in
5971column 8 and ends in a full stop, i.e. anything that could be a
5972paragraph name.
5973
5974*** Regexps in Etags now support intervals, as in ed or grep. The syntax of
5975an interval is \{M,N\}, and it means to match the preceding expression
5976at least M times and as many as N times.
5977
5978** The format for specifying a custom format for time-stamp to insert
5979in files has changed slightly.
5980
5981With the new enhancements to the functionality of format-time-string,
5982time-stamp-format will change to be eventually compatible with it.
5983This conversion is being done in two steps to maintain compatibility
5984with old time-stamp-format values.
5985
5986In the new scheme, alternate case is signified by the number-sign
5987(`#') modifier, rather than changing the case of the format character.
5988This feature is as yet incompletely implemented for compatibility
5989reasons.
5990
5991In the old time-stamp-format, all numeric fields defaulted to their
5992natural width. (With format-time-string, each format has a
5993fixed-width default.) In this version, you can specify the colon
5994(`:') modifier to a numeric conversion to mean "give me the historical
5995time-stamp-format width default." Do not use colon if you are
5996specifying an explicit width, as in "%02d".
5997
5998Numbers are no longer truncated to the requested width, except in the
5999case of "%02y", which continues to give a two-digit year. Digit
6000truncation probably wasn't being used for anything else anyway.
6001
6002The new formats will work with old versions of Emacs. New formats are
6003being recommended now to allow time-stamp-format to change in the
6004future to be compatible with format-time-string. The new forms being
6005recommended now will continue to work then.
6006
6007See the documentation string for the variable time-stamp-format for
6008details.
6009
6010** There are some additional major modes:
6011
6012dcl-mode, for editing VMS DCL files.
6013m4-mode, for editing files of m4 input.
6014meta-mode, for editing MetaFont and MetaPost source files.
6015
6016** In Shell mode, the command shell-copy-environment-variable lets you
6017copy the value of a specified environment variable from the subshell
6018into Emacs.
6019
6020** New Lisp packages include:
6021
6022*** battery.el displays battery status for laptops.
6023
6024*** M-x bruce (named after Lenny Bruce) is a program that might
6025be used for adding some indecent words to your email.
6026
6027*** M-x crisp-mode enables an emulation for the CRiSP editor.
6028
6029*** M-x dirtrack arranges for better tracking of directory changes
6030in shell buffers.
6031
6032*** The new library elint.el provides for linting of Emacs Lisp code.
6033See the documentation for `elint-initialize', `elint-current-buffer'
6034and `elint-defun'.
6035
6036*** M-x expand-add-abbrevs defines a special kind of abbrev which is
6037meant for programming constructs. These abbrevs expand like ordinary
6038ones, when you type SPC, but only at the end of a line and not within
6039strings or comments.
6040
6041These abbrevs can act as templates: you can define places within an
6042abbrev for insertion of additional text. Once you expand the abbrev,
6043you can then use C-x a p and C-x a n to move back and forth to these
6044insertion points. Thus you can conveniently insert additional text
6045at these points.
6046
6047*** filecache.el remembers the location of files so that you
6048can visit them by short forms of their names.
6049
6050*** find-func.el lets you find the definition of the user-loaded
6051Emacs Lisp function at point.
6052
6053*** M-x handwrite converts text to a "handwritten" picture.
6054
6055*** M-x iswitchb-buffer is a command for switching to a buffer, much like
6056switch-buffer, but it reads the argument in a more helpful way.
6057
6058*** M-x landmark implements a neural network for landmark learning.
6059
6060*** M-x locate provides a convenient interface to the `locate' program.
6061
6062*** M4 mode is a new mode for editing files of m4 input.
6063
6064*** mantemp.el creates C++ manual template instantiations
6065from the GCC error messages which indicate which instantiations are needed.
6066
6067*** mouse-copy.el provides a one-click copy and move feature.
6068You can drag a region with M-mouse-1, and it is automatically
6069inserted at point. M-Shift-mouse-1 deletes the text from its
6070original place after inserting the copy.
6071
6072*** mouse-drag.el lets you do scrolling by dragging Mouse-2
6073on the buffer.
6074
6075You click the mouse and move; that distance either translates into the
6076velocity to scroll (with mouse-drag-throw) or the distance to scroll
6077(with mouse-drag-drag). Horizontal scrolling is enabled when needed.
6078
6079Enable mouse-drag with:
6080 (global-set-key [down-mouse-2] 'mouse-drag-throw)
6081-or-
6082 (global-set-key [down-mouse-2] 'mouse-drag-drag)
6083
6084*** mspools.el is useful for determining which mail folders have
6085mail waiting to be read in them. It works with procmail.
6086
6087*** Octave mode is a major mode for editing files of input for Octave.
6088It comes with a facility for communicating with an Octave subprocess.
6089
6090*** ogonek
6091
6092The ogonek package provides functions for changing the coding of
6093Polish diacritic characters in buffers. Codings known from various
6094platforms are supported such as ISO8859-2, Mazovia, IBM Latin2, and
6095TeX. For example, you can change the coding from Mazovia to
6096ISO8859-2. Another example is a change of coding from ISO8859-2 to
6097prefix notation (in which `/a' stands for the aogonek character, for
6098instance) and vice versa.
6099
6100To use this package load it using
6101 M-x load-library [enter] ogonek
6102Then, you may get an explanation by calling one of
79214ddf 6103 M-x ogonek-jak -- in Polish
a933dad1
DL
6104 M-x ogonek-how -- in English
6105The info specifies the commands and variables provided as well as the
6106ways of customization in `.emacs'.
6107
6108*** Interface to ph.
6109
6110Emacs provides a client interface to CCSO Nameservers (ph/qi)
6111
6112The CCSO nameserver is used in many universities to provide directory
6113services about people. ph.el provides a convenient Emacs interface to
6114these servers.
6115
6116*** uce.el is useful for replying to unsolicited commercial email.
6117
6118*** vcursor.el implements a "virtual cursor" feature.
6119You can move the virtual cursor with special commands
6120while the real cursor does not move.
6121
6122*** webjump.el is a "hot list" package which you can set up
6123for visiting your favorite web sites.
6124
6125*** M-x winner-mode is a minor mode which saves window configurations,
6126so you can move back to other configurations that you have recently used.
6127
6128** movemail change
6129
6130Movemail no longer needs to be installed setuid root in order for POP
6131mail retrieval to function properly. This is because it no longer
6132supports the RPOP (reserved-port POP) protocol; instead, it uses the
6133user's POP password to authenticate to the mail server.
6134
6135This change was made earlier, but not reported in NEWS before.
6136\f
6137* Emacs 20.1 changes for MS-DOS and MS-Windows.
6138
6139** Changes in handling MS-DOS/MS-Windows text files.
6140
6141Emacs handles three different conventions for representing
6142end-of-line: CRLF for MSDOS, LF for Unix and GNU, and CR (used on the
6143Macintosh). Emacs determines which convention is used in a specific
6144file based on the contents of that file (except for certain special
6145file names), and when it saves the file, it uses the same convention.
6146
6147To save the file and change the end-of-line convention, you can use
6148C-x RET f (set-buffer-file-coding-system) to specify a different
6149coding system for the buffer. Then, when you save the file, the newly
6150specified coding system will take effect. For example, to save with
6151LF, specify undecided-unix (or some other ...-unix coding system); to
6152save with CRLF, specify undecided-dos.
6153\f
6154* Lisp Changes in Emacs 20.1
6155
6156** Byte-compiled files made with Emacs 20 will, in general, work in
6157Emacs 19 as well, as long as the source code runs in Emacs 19. And
6158vice versa: byte-compiled files made with Emacs 19 should also run in
6159Emacs 20, as long as the program itself works in Emacs 20.
6160
6161** Windows-specific functions and variables have been renamed
6162to start with w32- instead of win32-.
6163
6164In hacker language, calling something a "win" is a form of praise. We
6165don't want to praise a non-free Microsoft system, so we don't call it
6166"win".
6167
6168** Basic Lisp changes
6169
6170*** A symbol whose name starts with a colon now automatically
6171evaluates to itself. Therefore such a symbol can be used as a constant.
6172
6173*** The defined purpose of `defconst' has been changed. It should now
6174be used only for values that should not be changed whether by a program
6175or by the user.
6176
6177The actual behavior of defconst has not been changed.
6178
6179*** There are new macros `when' and `unless'
6180
6181(when CONDITION BODY...) is short for (if CONDITION (progn BODY...))
6182(unless CONDITION BODY...) is short for (if CONDITION nil BODY...)
6183
6184*** Emacs now defines functions caar, cadr, cdar and cddr with their
6185usual Lisp meanings. For example, caar returns the car of the car of
6186its argument.
6187
6188*** equal, when comparing strings, now ignores their text properties.
6189
6190*** The new function `functionp' tests whether an object is a function.
6191
6192*** arrayp now returns t for char-tables and bool-vectors.
6193
6194*** Certain primitives which use characters (as integers) now get an
6195error if the integer is not a valid character code. These primitives
6196include insert-char, char-to-string, and the %c construct in the
6197`format' function.
6198
6199*** The `require' function now insists on adding a suffix, either .el
6200or .elc, to the file name. Thus, (require 'foo) will not use a file
6201whose name is just foo. It insists on foo.el or foo.elc.
6202
6203*** The `autoload' function, when the file name does not contain
6204either a directory name or the suffix .el or .elc, insists on
6205adding one of these suffixes.
6206
6207*** string-to-number now takes an optional second argument BASE
6208which specifies the base to use when converting an integer.
79214ddf 6209If BASE is omitted, base 10 is used.
a933dad1
DL
6210
6211We have not implemented other radices for floating point numbers,
6212because that would be much more work and does not seem useful.
6213
6214*** substring now handles vectors as well as strings.
6215
6216*** The Common Lisp function eql is no longer defined normally.
6217You must load the `cl' library to define it.
6218
6219*** The new macro `with-current-buffer' lets you evaluate an expression
6220conveniently with a different current buffer. It looks like this:
6221
6222 (with-current-buffer BUFFER BODY-FORMS...)
6223
6224BUFFER is the expression that says which buffer to use.
6225BODY-FORMS say what to do in that buffer.
6226
6227*** The new primitive `save-current-buffer' saves and restores the
6228choice of current buffer, like `save-excursion', but without saving or
6229restoring the value of point or the mark. `with-current-buffer'
6230works using `save-current-buffer'.
6231
6232*** The new macro `with-temp-file' lets you do some work in a new buffer and
6233write the output to a specified file. Like `progn', it returns the value
6234of the last form.
6235
6236*** The new macro `with-temp-buffer' lets you do some work in a new buffer,
6237which is discarded after use. Like `progn', it returns the value of the
6238last form. If you wish to return the buffer contents, use (buffer-string)
6239as the last form.
6240
6241*** The new function split-string takes a string, splits it at certain
6242characters, and returns a list of the substrings in between the
6243matches.
6244
6245For example, (split-string "foo bar lose" " +") returns ("foo" "bar" "lose").
6246
6247*** The new macro with-output-to-string executes some Lisp expressions
6248with standard-output set up so that all output feeds into a string.
6249Then it returns that string.
6250
6251For example, if the current buffer name is `foo',
6252
6253(with-output-to-string
6254 (princ "The buffer is ")
6255 (princ (buffer-name)))
6256
6257returns "The buffer is foo".
6258
6259** Non-ASCII characters are now supported, if enable-multibyte-characters
6260is non-nil.
6261
6262These characters have character codes above 256. When inserted in the
6263buffer or stored in a string, they are represented as multibyte
6264characters that occupy several buffer positions each.
6265
6266*** When enable-multibyte-characters is non-nil, a single character in
6267a buffer or string can be two or more bytes (as many as four).
6268
6269Buffers and strings are still made up of unibyte elements;
6270character positions and string indices are always measured in bytes.
6271Therefore, moving forward one character can increase the buffer
6272position by 2, 3 or 4. The function forward-char moves by whole
6273characters, and therefore is no longer equivalent to
6274 (lambda (n) (goto-char (+ (point) n))).
6275
6276ASCII characters (codes 0 through 127) are still single bytes, always.
6277Sequences of byte values 128 through 255 are used to represent
6278non-ASCII characters. These sequences are called "multibyte
6279characters".
6280
6281The first byte of a multibyte character is always in the range 128
6282through 159 (octal 0200 through 0237). These values are called
6283"leading codes". The second and subsequent bytes are always in the
6284range 160 through 255 (octal 0240 through 0377). The first byte, the
6285leading code, determines how many bytes long the sequence is.
6286
6287*** The function forward-char moves over characters, and therefore
6288(forward-char 1) may increase point by more than 1 if it moves over a
6289multibyte character. Likewise, delete-char always deletes a
6290character, which may be more than one buffer position.
6291
6292This means that some Lisp programs, which assume that a character is
6293always one buffer position, need to be changed.
6294
6295However, all ASCII characters are always one buffer position.
79214ddf 6296
a933dad1
DL
6297*** The regexp [\200-\377] no longer matches all non-ASCII characters,
6298because when enable-multibyte-characters is non-nil, these characters
6299have codes that are not in the range octal 200 to octal 377. However,
6300the regexp [^\000-\177] does match all non-ASCII characters,
6301guaranteed.
6302
6303*** The function char-boundary-p returns non-nil if position POS is
6304between two characters in the buffer (not in the middle of a
6305character).
6306
6307When the value is non-nil, it says what kind of character follows POS:
6308
6309 0 if POS is at an ASCII character or at the end of range,
6310 1 if POS is before a 2-byte length multi-byte form,
6311 2 if POS is at a head of 3-byte length multi-byte form,
6312 3 if POS is at a head of 4-byte length multi-byte form,
6313 4 if POS is at a head of multi-byte form of a composite character.
6314
6315*** The function char-bytes returns how many bytes the character CHAR uses.
6316
6317*** Strings can contain multibyte characters. The function
6318`length' returns the string length counting bytes, which may be
6319more than the number of characters.
6320
6321You can include a multibyte character in a string constant by writing
6322it literally. You can also represent it with a hex escape,
6323\xNNNNNNN..., using as many digits as necessary. Any character which
6324is not a valid hex digit terminates this construct. If you want to
6325follow it with a character that is a hex digit, write backslash and
6326newline in between; that will terminate the hex escape.
6327
6328*** The function concat-chars takes arguments which are characters
6329and returns a string containing those characters.
6330
6331*** The function sref access a multibyte character in a string.
6332(sref STRING INDX) returns the character in STRING at INDEX. INDEX
6333counts from zero. If INDEX is at a position in the middle of a
6334character, sref signals an error.
6335
6336*** The function chars-in-string returns the number of characters
6337in a string. This is less than the length of the string, if the
6338string contains multibyte characters (the length counts bytes).
6339
6340*** The function chars-in-region returns the number of characters
6341in a region from BEG to END. This is less than (- END BEG) if the
6342region contains multibyte characters (the length counts bytes).
6343
6344*** The function string-to-list converts a string to a list of
6345the characters in it. string-to-vector converts a string
6346to a vector of the characters in it.
6347
6348*** The function store-substring alters part of the contents
6349of a string. You call it as follows:
6350
6351 (store-substring STRING IDX OBJ)
6352
6353This says to alter STRING, by storing OBJ starting at index IDX in
6354STRING. OBJ may be either a character or a (smaller) string.
6355This function really does alter the contents of STRING.
6356Since it is impossible to change the length of an existing string,
6357it is an error if OBJ doesn't fit within STRING's actual length.
6358
6359*** char-width returns the width (in columns) of the character CHAR,
6360if it were displayed in the current buffer and the selected window.
6361
6362*** string-width returns the width (in columns) of the text in STRING,
6363if it were displayed in the current buffer and the selected window.
6364
6365*** truncate-string-to-width shortens a string, if necessary,
6366to fit within a certain number of columns. (Of course, it does
6367not alter the string that you give it; it returns a new string
6368which contains all or just part of the existing string.)
6369
6370(truncate-string-to-width STR END-COLUMN &optional START-COLUMN PADDING)
6371
6372This returns the part of STR up to column END-COLUMN.
6373
6374The optional argument START-COLUMN specifies the starting column.
6375If this is non-nil, then the first START-COLUMN columns of the string
6376are not included in the resulting value.
6377
6378The optional argument PADDING, if non-nil, is a padding character to be added
6379at the beginning and end the resulting string, to extend it to exactly
6380WIDTH columns. If PADDING is nil, that means do not pad; then, if STRING
6381is narrower than WIDTH, the value is equal to STRING.
6382
6383If PADDING and START-COLUMN are both non-nil, and if there is no clean
6384place in STRING that corresponds to START-COLUMN (because one
6385character extends across that column), then the padding character
6386PADDING is added one or more times at the beginning of the result
6387string, so that its columns line up as if it really did start at
6388column START-COLUMN.
6389
6390*** When the functions in the list after-change-functions are called,
6391the third argument is the number of bytes in the pre-change text, not
6392necessarily the number of characters. It is, in effect, the
6393difference in buffer position between the beginning and the end of the
6394changed text, before the change.
6395
6396*** The characters Emacs uses are classified in various character
6397sets, each of which has a name which is a symbol. In general there is
6398one character set for each script, not for each language.
6399
6400**** The function charsetp tests whether an object is a character set name.
6401
6402**** The variable charset-list holds a list of character set names.
6403
6404**** char-charset, given a character code, returns the name of the character
6405set that the character belongs to. (The value is a symbol.)
6406
6407**** split-char, given a character code, returns a list containing the
6408name of the character set, followed by one or two byte-values
6409which identify the character within that character set.
6410
6411**** make-char, given a character set name and one or two subsequent
6412byte-values, constructs a character code. This is roughly the
6413opposite of split-char.
6414
6415**** find-charset-region returns a list of the character sets
6416of all the characters between BEG and END.
6417
6418**** find-charset-string returns a list of the character sets
6419of all the characters in a string.
6420
6421*** Here are the Lisp facilities for working with coding systems
6422and specifying coding systems.
6423
6424**** The function coding-system-list returns a list of all coding
6425system names (symbols). With optional argument t, it returns a list
6426of all distinct base coding systems, not including variants.
6427(Variant coding systems are those like latin-1-dos, latin-1-unix
6428and latin-1-mac which specify the end-of-line conversion as well
6429as what to do about code conversion.)
6430
6431**** coding-system-p tests a symbol to see if it is a coding system
6432name. It returns t if so, nil if not.
6433
6434**** file-coding-system-alist specifies which coding systems to use
6435for certain file names. It works like network-coding-system-alist,
6436except that the PATTERN is matched against the file name.
6437
6438Each element has the format (PATTERN . VAL), where PATTERN determines
6439which file names the element applies to. PATTERN should be a regexp
6440to match against a file name.
6441
6442VAL is a coding system, a cons cell containing two coding systems, or
6443a function symbol. If VAL is a coding system, it is used for both
6444decoding what received from the network stream and encoding what sent
6445to the network stream. If VAL is a cons cell containing two coding
6446systems, the car specifies the coding system for decoding, and the cdr
6447specifies the coding system for encoding.
6448
6449If VAL is a function symbol, the function must return a coding system
6450or a cons cell containing two coding systems, which is used as above.
6451
6452**** The variable network-coding-system-alist specifies
6453the coding system to use for network sockets.
6454
6455Each element has the format (PATTERN . VAL), where PATTERN determines
6456which network sockets the element applies to. PATTERN should be
6457either a port number or a regular expression matching some network
6458service names.
6459
6460VAL is a coding system, a cons cell containing two coding systems, or
6461a function symbol. If VAL is a coding system, it is used for both
6462decoding what received from the network stream and encoding what sent
6463to the network stream. If VAL is a cons cell containing two coding
6464systems, the car specifies the coding system for decoding, and the cdr
6465specifies the coding system for encoding.
6466
6467If VAL is a function symbol, the function must return a coding system
6468or a cons cell containing two coding systems, which is used as above.
6469
6470**** process-coding-system-alist specifies which coding systems to use
6471for certain subprocess. It works like network-coding-system-alist,
6472except that the PATTERN is matched against the program name used to
6473start the subprocess.
6474
6475**** The variable default-process-coding-system specifies the coding
6476systems to use for subprocess (and net connection) input and output,
6477when nothing else specifies what to do. The value is a cons cell
6478(OUTPUT-CODING . INPUT-CODING). OUTPUT-CODING applies to output
6479to the subprocess, and INPUT-CODING applies to input from it.
6480
6481**** The variable coding-system-for-write, if non-nil, specifies the
6482coding system to use for writing a file, or for output to a synchronous
6483subprocess.
6484
6485It also applies to any asynchronous subprocess or network connection,
6486but in a different way: the value of coding-system-for-write when you
6487start the subprocess or connection affects that subprocess or
6488connection permanently or until overridden.
6489
6490The variable coding-system-for-write takes precedence over
6491file-coding-system-alist, process-coding-system-alist and
6492network-coding-system-alist, and all other methods of specifying a
6493coding system for output. But most of the time this variable is nil.
6494It exists so that Lisp programs can bind it to a specific coding
6495system for one operation at a time.
6496
6497**** coding-system-for-read applies similarly to input from
6498files, subprocesses or network connections.
6499
6500**** The function process-coding-system tells you what
6501coding systems(s) an existing subprocess is using.
6502The value is a cons cell,
6503 (DECODING-CODING-SYSTEM . ENCODING-CODING-SYSTEM)
6504where DECODING-CODING-SYSTEM is used for decoding output from
6505the subprocess, and ENCODING-CODING-SYSTEM is used for encoding
6506input to the subprocess.
6507
6508**** The function set-process-coding-system can be used to
6509change the coding systems in use for an existing subprocess.
6510
6511** Emacs has a new facility to help users manage the many
6512customization options. To make a Lisp program work with this facility,
6513you need to use the new macros defgroup and defcustom.
6514
6515You use defcustom instead of defvar, for defining a user option
6516variable. The difference is that you specify two additional pieces of
6517information (usually): the "type" which says what values are
6518legitimate, and the "group" which specifies the hierarchy for
6519customization.
6520
6521Thus, instead of writing
6522
6523 (defvar foo-blurgoze nil
6524 "*Non-nil means that foo will act very blurgozely.")
6525
6526you would now write this:
6527
6528 (defcustom foo-blurgoze nil
6529 "*Non-nil means that foo will act very blurgozely."
6530 :type 'boolean
6531 :group foo)
6532
6533The type `boolean' means that this variable has only
6534two meaningful states: nil and non-nil. Other type values
6535describe other possibilities; see the manual for Custom
6536for a description of them.
6537
6538The "group" argument is used to specify a group which the option
6539should belong to. You define a new group like this:
6540
6541 (defgroup ispell nil
6542 "Spell checking using Ispell."
6543 :group 'processes)
6544
6545The "group" argument in defgroup specifies the parent group. The root
6546group is called `emacs'; it should not contain any variables itself,
6547but only other groups. The immediate subgroups of `emacs' correspond
6548to the keywords used by C-h p. Under these subgroups come
6549second-level subgroups that belong to individual packages.
6550
6551Each Emacs package should have its own set of groups. A simple
6552package should have just one group; a more complex package should
6553have a hierarchy of its own groups. The sole or root group of a
6554package should be a subgroup of one or more of the "keyword"
6555first-level subgroups.
6556
6557** New `widget' library for inserting UI components in buffers.
6558
6559This library, used by the new custom library, is documented in a
6560separate manual that accompanies Emacs.
6561
6562** easy-mmode
6563
6564The easy-mmode package provides macros and functions that make
6565developing minor modes easier. Roughly, the programmer has to code
6566only the functionality of the minor mode. All the rest--toggles,
6567predicate, and documentation--can be done in one call to the macro
6568`easy-mmode-define-minor-mode' (see the documentation). See also
6569`easy-mmode-define-keymap'.
6570
6571** Text property changes
6572
6573*** The `intangible' property now works on overlays as well as on a
6574text property.
6575
6576*** The new functions next-char-property-change and
6577previous-char-property-change scan through the buffer looking for a
6578place where either a text property or an overlay might change. The
6579functions take two arguments, POSITION and LIMIT. POSITION is the
6580starting position for the scan. LIMIT says where to stop the scan.
6581
6582If no property change is found before LIMIT, the value is LIMIT. If
6583LIMIT is nil, scan goes to the beginning or end of the accessible part
6584of the buffer. If no property change is found, the value is the
6585position of the beginning or end of the buffer.
6586
6587*** In the `local-map' text property or overlay property, the property
6588value can now be a symbol whose function definition is a keymap. This
6589is an alternative to using the keymap itself.
6590
6591** Changes in invisibility features
6592
6593*** Isearch can now temporarily show parts of the buffer which are
6594hidden by an overlay with a invisible property, when the search match
6595is inside that portion of the buffer. To enable this the overlay
6596should have a isearch-open-invisible property which is a function that
6597would be called having the overlay as an argument, the function should
6598make the overlay visible.
6599
6600During incremental search the overlays are shown by modifying the
6601invisible and intangible properties, if beside this more actions are
6602needed the overlay should have a isearch-open-invisible-temporary
6603which is a function. The function is called with 2 arguments: one is
6604the overlay and the second is nil when it should show the overlay and
6605t when it should hide it.
6606
6607*** add-to-invisibility-spec, remove-from-invisibility-spec
6608
6609Modes that use overlays to hide portions of a buffer should set the
79214ddf
FP
6610invisible property of the overlay to the mode's name (or another symbol)
6611and modify the `buffer-invisibility-spec' to include that symbol.
a933dad1 6612Use `add-to-invisibility-spec' and `remove-from-invisibility-spec' to
79214ddf 6613manipulate the `buffer-invisibility-spec'.
a933dad1
DL
6614Here is an example of how to do this:
6615
6616 ;; If we want to display an ellipsis:
79214ddf 6617 (add-to-invisibility-spec '(my-symbol . t))
a933dad1 6618 ;; If you don't want ellipsis:
79214ddf 6619 (add-to-invisibility-spec 'my-symbol)
a933dad1
DL
6620
6621 ...
6622 (overlay-put (make-overlay beginning end) 'invisible 'my-symbol)
6623
6624 ...
6625 ;; When done with the overlays:
6626 (remove-from-invisibility-spec '(my-symbol . t))
6627 ;; Or respectively:
6628 (remove-from-invisibility-spec 'my-symbol)
6629
6630** Changes in syntax parsing.
6631
6632*** The syntax-directed buffer-scan functions (such as
6633`parse-partial-sexp', `forward-word' and similar functions) can now
6634obey syntax information specified by text properties, if the variable
6635`parse-sexp-lookup-properties' is non-nil.
6636
6637If the value of `parse-sexp-lookup-properties' is nil, the behavior
6638is as before: the syntax-table of the current buffer is always
6639used to determine the syntax of the character at the position.
6640
6641When `parse-sexp-lookup-properties' is non-nil, the syntax of a
6642character in the buffer is calculated thus:
6643
6644 a) if the `syntax-table' text-property of that character
6645 is a cons, this cons becomes the syntax-type;
6646
6647 Valid values of `syntax-table' text-property are: nil, a valid
6648 syntax-table, and a valid syntax-table element, i.e.,
6649 a cons cell of the form (SYNTAX-CODE . MATCHING-CHAR).
6650
6651 b) if the character's `syntax-table' text-property
6652 is a syntax table, this syntax table is used
6653 (instead of the syntax-table of the current buffer) to
6654 determine the syntax type of the character.
6655
6656 c) otherwise the syntax-type is determined by the syntax-table
6657 of the current buffer.
6658
6659*** The meaning of \s in regular expressions is also affected by the
6660value of `parse-sexp-lookup-properties'. The details are the same as
6661for the syntax-directed buffer-scan functions.
6662
6663*** There are two new syntax-codes, `!' and `|' (numeric values 14
6664and 15). A character with a code `!' starts a comment which is ended
6665only by another character with the same code (unless quoted). A
6666character with a code `|' starts a string which is ended only by
6667another character with the same code (unless quoted).
6668
6669These codes are mainly meant for use as values of the `syntax-table'
6670text property.
6671
6672*** The function `parse-partial-sexp' has new semantics for the sixth
6673arg COMMENTSTOP. If it is `syntax-table', parse stops after the start
6674of a comment or a string, or after end of a comment or a string.
6675
6676*** The state-list which the return value from `parse-partial-sexp'
6677(and can also be used as an argument) now has an optional ninth
6678element: the character address of the start of last comment or string;
6679nil if none. The fourth and eighth elements have special values if the
6680string/comment is started by a "!" or "|" syntax-code.
6681
6682*** Since new features of `parse-partial-sexp' allow a complete
6683syntactic parsing, `font-lock' no longer supports
6684`font-lock-comment-start-regexp'.
6685
6686** Changes in face features
6687
6688*** The face functions are now unconditionally defined in Emacs, even
6689if it does not support displaying on a device that supports faces.
6690
6691*** The function face-documentation returns the documentation string
6692of a face (or nil if it doesn't have one).
6693
6694*** The function face-bold-p returns t if a face should be bold.
6695set-face-bold-p sets that flag.
6696
6697*** The function face-italic-p returns t if a face should be italic.
6698set-face-italic-p sets that flag.
6699
6700*** You can now specify foreground and background colors for text
6701by adding elements of the form (foreground-color . COLOR-NAME)
6702and (background-color . COLOR-NAME) to the list of faces in
6703the `face' property (either the character's text property or an
6704overlay property).
6705
6706This means that you no longer need to create named faces to use
6707arbitrary colors in a Lisp package.
6708
6709** Changes in file-handling functions
6710
6711*** File-access primitive functions no longer discard an extra redundant
6712directory name from the beginning of the file name. In other words,
6713they no longer do anything special with // or /~. That conversion
6714is now done only in substitute-in-file-name.
6715
6716This makes it possible for a Lisp program to open a file whose name
6717begins with ~.
6718
6719*** If copy-file is unable to set the date of the output file,
6720it now signals an error with the condition file-date-error.
6721
6722*** The inode number returned by file-attributes may be an integer (if
6723the number fits in a Lisp integer) or a list of integers.
6724
6725*** insert-file-contents can now read from a special file,
6726as long as the arguments VISIT and REPLACE are nil.
6727
6728*** The RAWFILE arg to find-file-noselect, if non-nil, now suppresses
6729character code conversion as well as other things.
6730
6731Meanwhile, this feature does work with remote file names
6732(formerly it did not).
6733
6734*** Lisp packages which create temporary files should use the TMPDIR
6735environment variable to decide which directory to put them in.
6736
6737*** interpreter-mode-alist elements now specify regexps
6738instead of constant strings.
6739
6740*** expand-file-name no longer treats `//' or `/~' specially. It used
6741to delete all the text of a file name up through the first slash of
6742any `//' or `/~' sequence. Now it passes them straight through.
6743
6744substitute-in-file-name continues to treat those sequences specially,
6745in the same way as before.
6746
6747*** The variable `format-alist' is more general now.
6748The FROM-FN and TO-FN in a format definition can now be strings
6749which specify shell commands to use as filters to perform conversion.
6750
6751*** The new function access-file tries to open a file, and signals an
6752error if that fails. If the open succeeds, access-file does nothing
6753else, and returns nil.
6754
6755*** The function insert-directory now signals an error if the specified
6756directory cannot be listed.
6757
6758** Changes in minibuffer input
6759
6760*** The functions read-buffer, read-variable, read-command, read-string
6761read-file-name, read-from-minibuffer and completing-read now take an
6762additional argument which specifies the default value. If this
6763argument is non-nil, it should be a string; that string is used in two
6764ways:
6765
6766 It is returned if the user enters empty input.
6767 It is available through the history command M-n.
6768
6769*** The functions read-string, read-from-minibuffer,
6770read-no-blanks-input and completing-read now take an additional
6771argument INHERIT-INPUT-METHOD. If this is non-nil, then the
6772minibuffer inherits the current input method and the setting of
6773enable-multibyte-characters from the previously current buffer.
6774
6775In an interactive spec, you can use M instead of s to read an
6776argument in this way.
6777
6778*** All minibuffer input functions discard text properties
6779from the text you enter in the minibuffer, unless the variable
6780minibuffer-allow-text-properties is non-nil.
6781
6782** Echo area features
6783
6784*** Clearing the echo area now runs the normal hook
6785echo-area-clear-hook. Note that the echo area can be used while the
6786minibuffer is active; in that case, the minibuffer is still active
6787after the echo area is cleared.
6788
6789*** The function current-message returns the message currently displayed
6790in the echo area, or nil if there is none.
6791
6792** Keyboard input features
6793
6794*** tty-erase-char is a new variable that reports which character was
6795set up as the terminal's erase character when time Emacs was started.
6796
6797*** num-nonmacro-input-events is the total number of input events
6798received so far from the terminal. It does not count those generated
6799by keyboard macros.
6800
6801** Frame-related changes
6802
6803*** make-frame runs the normal hook before-make-frame-hook just before
6804creating a frame, and just after creating a frame it runs the abnormal
6805hook after-make-frame-functions with the new frame as arg.
6806
6807*** The new hook window-configuration-change-hook is now run every time
6808the window configuration has changed. The frame whose configuration
6809has changed is the selected frame when the hook is run.
6810
6811*** Each frame now independently records the order for recently
6812selected buffers, in its buffer-list frame parameter, so that the
6813value of other-buffer is now based on the buffers recently displayed
6814in the selected frame.
6815
6816*** The value of the frame parameter vertical-scroll-bars
6817is now `left', `right' or nil. A non-nil value specifies
6818which side of the window to put the scroll bars on.
6819
6820** X Windows features
6821
6822*** You can examine X resources for other applications by binding
6823x-resource-class around a call to x-get-resource. The usual value of
6824x-resource-class is "Emacs", which is the correct value for Emacs.
6825
6826*** In menus, checkboxes and radio buttons now actually work.
6827The menu displays the current status of the box or button.
6828
6829*** The function x-list-fonts now takes an optional fourth argument
6830MAXIMUM which sets a limit on how many matching fonts to return.
6831A smaller value of MAXIMUM makes the function faster.
6832
6833If the only question is whether *any* font matches the pattern,
6834it is good to supply 1 for this argument.
6835
6836** Subprocess features
6837
6838*** A reminder: it is no longer necessary for subprocess filter
6839functions and sentinels to do save-match-data, because Emacs does this
6840automatically.
6841
6842*** The new function shell-command-to-string executes a shell command
6843and returns the output from the command as a string.
6844
6845*** The new function process-contact returns t for a child process,
6846and (HOSTNAME SERVICE) for a net connection.
6847
6848** An error in running pre-command-hook or post-command-hook
6849does clear the variable to nil. The documentation was wrong before.
6850
6851** In define-key-after, if AFTER is t, the new binding now always goes
6852at the end of the keymap. If the keymap is a menu, this means it
6853goes after the other menu items.
6854
6855** If you have a program that makes several changes in the same area
79214ddf 6856of the buffer, you can use the macro combine-after-change-calls
a933dad1
DL
6857around that Lisp code to make it faster when after-change hooks
6858are in use.
6859
6860The macro arranges to call the after-change functions just once for a
6861series of several changes--if that seems safe.
6862
6863Don't alter the variables after-change-functions and
6864after-change-function within the body of a combine-after-change-calls
6865form.
6866
6867** If you define an abbrev (with define-abbrev) whose EXPANSION
6868is not a string, then the abbrev does not expand in the usual sense,
6869but its hook is still run.
6870
6871** Normally, the Lisp debugger is not used (even if you have enabled it)
6872for errors that are handled by condition-case.
6873
6874If you set debug-on-signal to a non-nil value, then the debugger is called
6875regardless of whether there is a handler for the condition. This is
6876useful for debugging problems that happen inside of a condition-case.
6877
6878This mode of operation seems to be unreliable in other ways. Errors that
6879are normal and ought to be handled, perhaps in timers or process
6880filters, will instead invoke the debugger. So don't say you weren't
6881warned.
6882
6883** The new variable ring-bell-function lets you specify your own
6884way for Emacs to "ring the bell".
6885
6886** If run-at-time's TIME argument is t, the action is repeated at
6887integral multiples of REPEAT from the epoch; this is useful for
6888functions like display-time.
6889
6890** You can use the function locate-library to find the precise file
6891name of a Lisp library. This isn't new, but wasn't documented before.
6892
6893** Commands for entering view mode have new optional arguments that
6894can be used from Lisp. Low-level entrance to and exit from view mode
6895is done by functions view-mode-enter and view-mode-exit.
6896
6897** batch-byte-compile-file now makes Emacs return a nonzero status code
6898if there is an error in compilation.
6899
6900** pop-to-buffer, switch-to-buffer-other-window and
6901switch-to-buffer-other-frame now accept an additional optional
6902argument NORECORD, much like switch-to-buffer. If it is non-nil,
6903they don't put the buffer at the front of the buffer list.
6904
6905** If your .emacs file leaves the *scratch* buffer non-empty,
6906Emacs does not display the startup message, so as to avoid changing
6907the *scratch* buffer.
6908
6909** The new function regexp-opt returns an efficient regexp to match a string.
6910The arguments are STRINGS and (optionally) PAREN. This function can be used
6911where regexp matching or searching is intensively used and speed is important,
6912e.g., in Font Lock mode.
6913
6914** The variable buffer-display-count is local to each buffer,
6915and is incremented each time the buffer is displayed in a window.
6916It starts at 0 when the buffer is created.
6917
6918** The new function compose-mail starts composing a mail message
6919using the user's chosen mail composition agent (specified with the
6920variable mail-user-agent). It has variants compose-mail-other-window
6921and compose-mail-other-frame.
6922
6923** The `user-full-name' function now takes an optional parameter which
6924can either be a number (the UID) or a string (the login name). The
6925full name of the specified user will be returned.
6926
6927** Lisp packages that load files of customizations, or any other sort
6928of user profile, should obey the variable init-file-user in deciding
6929where to find it. They should load the profile of the user name found
6930in that variable. If init-file-user is nil, meaning that the -q
6931option was used, then Lisp packages should not load the customization
6932files at all.
6933
6934** format-time-string now allows you to specify the field width
6935and type of padding. This works as in printf: you write the field
6936width as digits in the middle of a %-construct. If you start
6937the field width with 0, it means to pad with zeros.
6938
6939For example, %S normally specifies the number of seconds since the
6940minute; %03S means to pad this with zeros to 3 positions, %_3S to pad
6941with spaces to 3 positions. Plain %3S pads with zeros, because that
6942is how %S normally pads to two positions.
6943
6944** thing-at-point now supports a new kind of "thing": url.
6945
6946** imenu.el changes.
6947
6948You can now specify a function to be run when selecting an
79214ddf 6949item from menu created by imenu.
a933dad1
DL
6950
6951An example of using this feature: if we define imenu items for the
6952#include directives in a C file, we can open the included file when we
6953select one of those items.
6954\f
6955* Emacs 19.34 is a bug-fix release with no user-visible changes.
6956\f
6957* Changes in Emacs 19.33.
6958
6959** Bibtex mode no longer turns on Auto Fill automatically. (No major
6960mode should do that--it is the user's choice.)
6961
6962** The variable normal-auto-fill-function specifies the function to
6963use for auto-fill-function, if and when Auto Fill is turned on.
6964Major modes can set this locally to alter how Auto Fill works.
6965\f
6966* Editing Changes in Emacs 19.32
6967
6968** C-x f with no argument now signals an error.
6969To set the fill column at the current column, use C-u C-x f.
6970
6971** Expanding dynamic abbrevs with M-/ is now smarter about case
6972conversion. If you type the abbreviation with mixed case, and it
6973matches the beginning of the expansion including case, then the
6974expansion is copied verbatim. Using SPC M-/ to copy an additional
6975word always copies it verbatim except when the previous copied word is
6976all caps.
6977
6978** On a non-windowing terminal, which can display only one Emacs frame
6979at a time, creating a new frame with C-x 5 2 also selects that frame.
6980
6981When using a display that can show multiple frames at once, C-x 5 2
6982does make the frame visible, but does not select it. This is the same
6983as in previous Emacs versions.
6984
6985** You can use C-x 5 2 to create multiple frames on MSDOS, just as on a
6986non-X terminal on Unix. Of course, only one frame is visible at any
6987time, since your terminal doesn't have the ability to display multiple
6988frames.
6989
6990** On Windows, set win32-pass-alt-to-system to a non-nil value
6991if you would like tapping the Alt key to invoke the Windows menu.
6992This feature is not enabled by default; since the Alt key is also the
6993Meta key, it is too easy and painful to activate this feature by
6994accident.
6995
6996** The command apply-macro-to-region-lines repeats the last defined
6997keyboard macro once for each complete line within the current region.
6998It does this line by line, by moving point to the beginning of that
6999line and then executing the macro.
7000
7001This command is not new, but was never documented before.
7002
7003** You can now use Mouse-1 to place the region around a string constant
7004(something surrounded by doublequote characters or other delimiter
7005characters of like syntax) by double-clicking on one of the delimiting
7006characters.
7007
7008** Font Lock mode
7009
7010*** Font Lock support modes
7011
7012Font Lock can be configured to use Fast Lock mode and Lazy Lock mode (see
7013below) in a flexible way. Rather than adding the appropriate function to the
7014hook font-lock-mode-hook, you can use the new variable font-lock-support-mode
7015to control which modes have Fast Lock mode or Lazy Lock mode turned on when
7016Font Lock mode is enabled.
7017
7018For example, to use Fast Lock mode when Font Lock mode is turned on, put:
7019
7020 (setq font-lock-support-mode 'fast-lock-mode)
7021
7022in your ~/.emacs.
7023
7024*** lazy-lock
7025
7026The lazy-lock package speeds up Font Lock mode by making fontification occur
7027only when necessary, such as when a previously unfontified part of the buffer
7028becomes visible in a window. When you create a buffer with Font Lock mode and
7029Lazy Lock mode turned on, the buffer is not fontified. When certain events
7030occur (such as scrolling), Lazy Lock makes sure that the visible parts of the
7031buffer are fontified. Lazy Lock also defers on-the-fly fontification until
7032Emacs has been idle for a given amount of time.
7033
7034To use this package, put in your ~/.emacs:
7035
7036 (setq font-lock-support-mode 'lazy-lock-mode)
7037
7038To control the package behaviour, see the documentation for `lazy-lock-mode'.
7039
7040** Changes in BibTeX mode.
7041
7042*** For all entries allow spaces and tabs between opening brace or
7043paren and key.
7044
7045*** Non-escaped double-quoted characters (as in `Sch"of') are now
7046supported.
7047
7048** Gnus changes.
7049
7050Gnus, the Emacs news reader, has undergone further rewriting. Many new
7051commands and variables have been added. There should be no
7052significant incompatibilities between this Gnus version and the
7053previously released version, except in the message composition area.
7054
7055Below is a list of the more user-visible changes. Coding changes
7056between Gnus 5.1 and 5.2 are more extensive.
7057
79214ddf 7058*** A new message composition mode is used. All old customization
a933dad1
DL
7059variables for mail-mode, rnews-reply-mode and gnus-msg are now
7060obsolete.
7061
7062*** Gnus is now able to generate "sparse" threads -- threads where
7063missing articles are represented by empty nodes.
7064
7065 (setq gnus-build-sparse-threads 'some)
7066
7067*** Outgoing articles are stored on a special archive server.
7068
7069 To disable this: (setq gnus-message-archive-group nil)
7070
7071*** Partial thread regeneration now happens when articles are
79214ddf 7072referred.
a933dad1
DL
7073
7074*** Gnus can make use of GroupLens predictions:
7075
7076 (setq gnus-use-grouplens t)
7077
7078*** A trn-line tree buffer can be displayed.
7079
7080 (setq gnus-use-trees t)
7081
7082*** An nn-like pick-and-read minor mode is available for the summary
79214ddf 7083buffers.
a933dad1
DL
7084
7085 (add-hook 'gnus-summary-mode-hook 'gnus-pick-mode)
7086
7087*** In binary groups you can use a special binary minor mode:
7088
7089 `M-x gnus-binary-mode'
7090
7091*** Groups can be grouped in a folding topic hierarchy.
7092
7093 (add-hook 'gnus-group-mode-hook 'gnus-topic-mode)
7094
7095*** Gnus can re-send and bounce mail.
7096
7097 Use the `S D r' and `S D b'.
7098
7099*** Groups can now have a score, and bubbling based on entry frequency
7100is possible.
7101
7102 (add-hook 'gnus-summary-exit-hook 'gnus-summary-bubble-group)
7103
7104*** Groups can be process-marked, and commands can be performed on
7105groups of groups.
7106
7107*** Caching is possible in virtual groups.
7108
7109*** nndoc now understands all kinds of digests, mail boxes, rnews news
79214ddf 7110batches, ClariNet briefs collections, and just about everything else.
a933dad1
DL
7111
7112*** Gnus has a new backend (nnsoup) to create/read SOUP packets.
7113
7114*** The Gnus cache is much faster.
7115
7116*** Groups can be sorted according to many criteria.
7117
7118 For instance: (setq gnus-group-sort-function 'gnus-group-sort-by-rank)
7119
7120*** New group parameters have been introduced to set list-address and
7121expiration times.
7122
7123*** All formatting specs allow specifying faces to be used.
7124
7125*** There are several more commands for setting/removing/acting on
7126process marked articles on the `M P' submap.
7127
7128*** The summary buffer can be limited to show parts of the available
7129articles based on a wide range of criteria. These commands have been
7130bound to keys on the `/' submap.
7131
7132*** Articles can be made persistent -- as an alternative to saving
7133articles with the `*' command.
7134
7135*** All functions for hiding article elements are now toggles.
7136
7137*** Article headers can be buttonized.
7138
7139 (add-hook 'gnus-article-display-hook 'gnus-article-add-buttons-to-head)
7140
7141*** All mail backends support fetching articles by Message-ID.
7142
79214ddf 7143*** Duplicate mail can now be treated properly. See the
a933dad1
DL
7144`nnmail-treat-duplicates' variable.
7145
7146*** All summary mode commands are available directly from the article
79214ddf 7147buffer.
a933dad1
DL
7148
7149*** Frames can be part of `gnus-buffer-configuration'.
7150
7151*** Mail can be re-scanned by a daemonic process.
7152
7153*** Gnus can make use of NoCeM files to filter spam.
7154
7155 (setq gnus-use-nocem t)
7156
79214ddf 7157*** Groups can be made permanently visible.
a933dad1
DL
7158
7159 (setq gnus-permanently-visible-groups "^nnml:")
7160
79214ddf 7161*** Many new hooks have been introduced to make customizing easier.
a933dad1
DL
7162
7163*** Gnus respects the Mail-Copies-To header.
7164
79214ddf 7165*** Threads can be gathered by looking at the References header.
a933dad1 7166
79214ddf 7167 (setq gnus-summary-thread-gathering-function
a933dad1
DL
7168 'gnus-gather-threads-by-references)
7169
7170*** Read articles can be stored in a special backlog buffer to avoid
79214ddf 7171refetching.
a933dad1
DL
7172
7173 (setq gnus-keep-backlog 50)
7174
7175*** A clean copy of the current article is always stored in a separate
7176buffer to allow easier treatment.
7177
7178*** Gnus can suggest where to save articles. See `gnus-split-methods'.
7179
7180*** Gnus doesn't have to do as much prompting when saving.
7181
7182 (setq gnus-prompt-before-saving t)
7183
7184*** gnus-uu can view decoded files asynchronously while fetching
79214ddf 7185articles.
a933dad1
DL
7186
7187 (setq gnus-uu-grabbed-file-functions 'gnus-uu-grab-view)
7188
79214ddf 7189*** Filling in the article buffer now works properly on cited text.
a933dad1
DL
7190
7191*** Hiding cited text adds buttons to toggle hiding, and how much
7192cited text to hide is now customizable.
7193
7194 (setq gnus-cited-lines-visible 2)
7195
7196*** Boring headers can be hidden.
7197
7198 (add-hook 'gnus-article-display-hook 'gnus-article-hide-boring-headers)
7199
7200*** Default scoring values can now be set from the menu bar.
7201
7202*** Further syntax checking of outgoing articles have been added.
7203
7204The Gnus manual has been expanded. It explains all these new features
7205in greater detail.
7206\f
7207* Lisp Changes in Emacs 19.32
7208
7209** The function set-visited-file-name now accepts an optional
7210second argument NO-QUERY. If it is non-nil, then the user is not
7211asked for confirmation in the case where the specified file already
7212exists.
7213
7214** The variable print-length applies to printing vectors and bitvectors,
7215as well as lists.
7216
7217** The new function keymap-parent returns the parent keymap
7218of a given keymap.
7219
7220** The new function set-keymap-parent specifies a new parent for a
7221given keymap. The arguments are KEYMAP and PARENT. PARENT must be a
7222keymap or nil.
7223
7224** Sometimes menu keymaps use a command name, a symbol, which is really
7225an automatically generated alias for some other command, the "real"
7226name. In such a case, you should give that alias symbol a non-nil
7227menu-alias property. That property tells the menu system to look for
7228equivalent keys for the real name instead of equivalent keys for the
7229alias.
7230\f
7231* Editing Changes in Emacs 19.31
7232
7233** Freedom of the press restricted in the United States.
7234
7235Emacs has been censored in accord with the Communications Decency Act.
7236This includes removing some features of the doctor program. That law
7237was described by its supporters as a ban on pornography, but it bans
7238far more than that. The Emacs distribution has never contained any
7239pornography, but parts of it were nonetheless prohibited.
7240
7241For information on US government censorship of the Internet, and what
7242you can do to bring back freedom of the press, see the web site
7243`http://www.vtw.org/'.
7244
7245** A note about C mode indentation customization.
7246
7247The old (Emacs 19.29) ways of specifying a C indentation style
7248do not normally work in the new implementation of C mode.
7249It has its own methods of customizing indentation, which are
7250much more powerful than the old C mode. See the Editing Programs
7251chapter of the manual for details.
7252
7253However, you can load the library cc-compat to make the old
7254customization variables take effect.
7255
7256** Marking with the mouse.
7257
7258When you mark a region with the mouse, the region now remains
7259highlighted until the next input event, regardless of whether you are
7260using M-x transient-mark-mode.
7261
7262** Improved Windows NT/95 support.
7263
7264*** Emacs now supports scroll bars on Windows NT and Windows 95.
7265
7266*** Emacs now supports subprocesses on Windows 95. (Subprocesses used
7267to work on NT only and not on 95.)
7268
7269*** There are difficulties with subprocesses, though, due to problems
7270in Windows, beyond the control of Emacs. They work fine as long as
7271you run Windows applications. The problems arise when you run a DOS
7272application in a subprocesses. Since current shells run as DOS
7273applications, these problems are significant.
7274
7275If you run a DOS application in a subprocess, then the application is
7276likely to busy-wait, which means that your machine will be 100% busy.
7277However, if you don't mind the temporary heavy load, the subprocess
7278will work OK as long as you tell it to terminate before you start any
7279other DOS application as a subprocess.
7280
7281Emacs is unable to terminate or interrupt a DOS subprocess.
7282You have to do this by providing input directly to the subprocess.
7283
7284If you run two DOS applications at the same time in two separate
7285subprocesses, even if one of them is asynchronous, you will probably
7286have to reboot your machine--until then, it will remain 100% busy.
7287Windows simply does not cope when one Windows process tries to run two
7288separate DOS subprocesses. Typing CTL-ALT-DEL and then choosing
7289Shutdown seems to work although it may take a few minutes.
7290
7291** M-x resize-minibuffer-mode.
7292
7293This command, not previously mentioned in NEWS, toggles a mode in
7294which the minibuffer window expands to show as many lines as the
7295minibuffer contains.
7296
7297** `title' frame parameter and resource.
7298
7299The `title' X resource now specifies just the frame title, nothing else.
7300It does not affect the name used for looking up other X resources.
7301It works by setting the new `title' frame parameter, which likewise
7302affects just the displayed title of the frame.
7303
7304The `name' parameter continues to do what it used to do:
7305it specifies the frame name for looking up X resources,
7306and also serves as the default for the displayed title
7307when the `title' parameter is unspecified or nil.
7308
7309** Emacs now uses the X toolkit by default, if you have a new
7310enough version of X installed (X11R5 or newer).
7311
7312** When you compile Emacs with the Motif widget set, Motif handles the
7313F10 key by activating the menu bar. To avoid confusion, the usual
7314Emacs binding of F10 is replaced with a no-op when using Motif.
7315
7316If you want to be able to use F10 in Emacs, you can rebind the Motif
7317menubar to some other key which you don't use. To do so, add
7318something like this to your X resources file. This example rebinds
7319the Motif menu bar activation key to S-F12:
7320
7321 Emacs*defaultVirtualBindings: osfMenuBar : Shift<Key>F12
7322
7323** In overwrite mode, DEL now inserts spaces in most cases
7324to replace the characters it "deletes".
7325
7326** The Rmail summary now shows the number of lines in each message.
7327
7328** Rmail has a new command M-x unforward-rmail-message, which extracts
7329a forwarded message from the message that forwarded it. To use it,
7330select a message which contains a forwarded message and then type the command.
7331It inserts the forwarded message as a separate Rmail message
7332immediately after the selected one.
7333
7334This command also undoes the textual modifications that are standardly
7335made, as part of forwarding, by Rmail and other mail reader programs.
7336
7337** Turning off saving of .saves-... files in your home directory.
7338
7339Each Emacs session writes a file named .saves-... in your home
7340directory to record which files M-x recover-session should recover.
7341If you exit Emacs normally with C-x C-c, it deletes that file. If
7342Emacs or the operating system crashes, the file remains for M-x
7343recover-session.
7344
7345You can turn off the writing of these files by setting
7346auto-save-list-file-name to nil. If you do this, M-x recover-session
7347will not work.
7348
7349Some previous Emacs versions failed to delete these files even on
7350normal exit. This is fixed now. If you are thinking of turning off
7351this feature because of past experiences with versions that had this
7352bug, it would make sense to check whether you still want to do so
7353now that the bug is fixed.
7354
7355** Changes to Version Control (VC)
7356
7357There is a new variable, vc-follow-symlinks. It indicates what to do
7358when you visit a link to a file that is under version control.
7359Editing the file through the link bypasses the version control system,
7360which is dangerous and probably not what you want.
7361
7362If this variable is t, VC follows the link and visits the real file,
7363telling you about it in the echo area. If it is `ask' (the default),
7364VC asks for confirmation whether it should follow the link. If nil,
7365the link is visited and a warning displayed.
7366
7367** iso-acc.el now lets you specify a choice of language.
7368Languages include "latin-1" (the default) and "latin-2" (which
7369is designed for entering ISO Latin-2 characters).
7370
7371There are also choices for specific human languages such as French and
7372Portuguese. These are subsets of Latin-1, which differ in that they
7373enable only the accent characters needed for particular language.
7374The other accent characters, not needed for the chosen language,
7375remain normal.
7376
7377** Posting articles and sending mail now has M-TAB completion on various
7378header fields (Newsgroups, To, CC, ...).
7379
7380Completion in the Newsgroups header depends on the list of groups
7381known to your news reader. Completion in the Followup-To header
7382offers those groups which are in the Newsgroups header, since
7383Followup-To usually just holds one of those.
7384
7385Completion in fields that hold mail addresses works based on the list
7386of local users plus your aliases. Additionally, if your site provides
7387a mail directory or a specific host to use for any unrecognized user
7388name, you can arrange to query that host for completion also. (See the
7389documentation of variables `mail-directory-process' and
7390`mail-directory-stream'.)
7391
7392** A greatly extended sgml-mode offers new features such as (to be configured)
7393skeletons with completing read for tags and attributes, typing named
7394characters including optionally all 8bit characters, making tags invisible
7395with optional alternate display text, skipping and deleting tag(pair)s.
7396
7397Note: since Emacs' syntax feature cannot limit the special meaning of ', " and
7398- to inside <>, for some texts the result, especially of font locking, may be
7399wrong (see `sgml-specials' if you get wrong results).
7400
7401The derived html-mode configures this with tags and attributes more or
7402less HTML3ish. It also offers optional quick keys like C-c 1 for
7403headline or C-c u for unordered list (see `html-quick-keys'). Edit /
7404Text Properties / Face or M-g combinations create tags as applicable.
7405Outline minor mode is supported and level 1 font-locking tries to
7406fontify tag contents (which only works when they fit on one line, due
7407to a limitation in font-lock).
7408
7409External viewing via browse-url can occur automatically upon saving.
7410
7411** M-x imenu-add-to-menubar now adds to the menu bar for the current
7412buffer only. If you want to put an Imenu item in the menu bar for all
7413buffers that use a particular major mode, use the mode hook, as in
7414this example:
7415
7416 (add-hook 'emacs-lisp-mode-hook
7417 '(lambda () (imenu-add-to-menubar "Index")))
7418
7419** Changes in BibTeX mode.
7420
7421*** Field names may now contain digits, hyphens, and underscores.
7422
7423*** Font Lock mode is now supported.
7424
7425*** bibtex-make-optional-field is no longer interactive.
7426
7427*** If bibtex-maintain-sorted-entries is non-nil, inserting new
7428entries is now done with a faster algorithm. However, inserting
7429will fail in this case if the buffer contains invalid entries or
7430isn't in sorted order, so you should finish each entry with C-c C-c
7431(bibtex-close-entry) after you have inserted or modified it.
7432The default value of bibtex-maintain-sorted-entries is nil.
7433
7434*** Function `show-all' is no longer bound to a key, since C-u C-c C-q
7435does the same job.
7436
7437*** Entries with quotes inside quote-delimited fields (as `author =
7438"Stefan Sch{\"o}f"') are now supported.
7439
7440*** Case in field names doesn't matter anymore when searching for help
7441text.
7442
7443** Font Lock mode
7444
7445*** Global Font Lock mode
7446
7447Font Lock mode can be turned on globally, in buffers that support it, by the
7448new command global-font-lock-mode. You can use the new variable
7449font-lock-global-modes to control which modes have Font Lock mode automagically
7450turned on. By default, this variable is set so that Font Lock mode is turned
7451on globally where the buffer mode supports it.
7452
7453For example, to automagically turn on Font Lock mode where supported, put:
7454
7455 (global-font-lock-mode t)
7456
7457in your ~/.emacs.
7458
7459*** Local Refontification
7460
7461In Font Lock mode, editing a line automatically refontifies that line only.
7462However, if your change alters the syntactic context for following lines,
7463those lines remain incorrectly fontified. To refontify them, use the new
7464command M-g M-g (font-lock-fontify-block).
7465
7466In certain major modes, M-g M-g refontifies the entire current function.
7467(The variable font-lock-mark-block-function controls how to find the
7468current function.) In other major modes, M-g M-g refontifies 16 lines
7469above and below point.
7470
7471With a prefix argument N, M-g M-g refontifies N lines above and below point.
7472
7473** Follow mode
7474
7475Follow mode is a new minor mode combining windows showing the same
7476buffer into one tall "virtual window". The windows are typically two
7477side-by-side windows. Follow mode makes them scroll together as if
7478they were a unit. To use it, go to a frame with just one window,
7479split it into two side-by-side windows using C-x 3, and then type M-x
7480follow-mode.
7481
7482M-x follow-mode turns off Follow mode if it is already enabled.
7483
7484To display two side-by-side windows and activate Follow mode, use the
7485command M-x follow-delete-other-windows-and-split.
7486
7487** hide-show changes.
7488
7489The hooks hs-hide-hooks and hs-show-hooks have been renamed
7490to hs-hide-hook and hs-show-hook, to follow the convention for
7491normal hooks.
7492
7493** Simula mode now has a menu containing the most important commands.
7494The new command simula-indent-exp is bound to C-M-q.
7495
7496** etags can now handle programs written in Erlang. Files are
7497recognised by the extensions .erl and .hrl. The tagged lines are
7498those that begin a function, record, or macro.
7499
7500** MSDOS Changes
7501
7502*** It is now possible to compile Emacs with the version 2 of DJGPP.
7503Compilation with DJGPP version 1 also still works.
7504
7505*** The documentation of DOS-specific aspects of Emacs was rewritten
7506and expanded; see the ``MS-DOS'' node in the on-line docs.
7507
7508*** Emacs now uses ~ for backup file names, not .bak.
7509
7510*** You can simulate mouse-3 on two-button mice by simultaneously
7511pressing both mouse buttons.
7512
7513*** A number of packages and commands which previously failed or had
7514restricted functionality on MS-DOS, now work. The most important ones
79214ddf 7515are:
a933dad1
DL
7516
7517**** Printing (both with `M-x lpr-buffer' and with `ps-print' package)
7518now works.
7519
7520**** `Ediff' works (in a single-frame mode).
7521
7522**** `M-x display-time' can be used on MS-DOS (due to the new
7523implementation of Emacs timers, see below).
7524
7525**** `Dired' supports Unix-style shell wildcards.
7526
7527**** The `c-macro-expand' command now works as on other platforms.
7528
7529**** `M-x recover-session' works.
7530
7531**** `M-x list-colors-display' displays all the available colors.
7532
7533**** The `TPU-EDT' package works.
7534\f
7535* Lisp changes in Emacs 19.31.
7536
7537** The function using-unix-filesystems on Windows NT and Windows 95
7538tells Emacs to read and write files assuming that they reside on a
7539remote Unix filesystem. No CR/LF translation is done on any files in
7540this case. Invoking using-unix-filesystems with t activates this
7541behavior, and invoking it with any other value deactivates it.
7542
7543** Change in system-type and system-configuration values.
7544
7545The value of system-type on a Linux-based GNU system is now `lignux',
7546not `linux'. This means that some programs which use `system-type'
7547need to be changed. The value of `system-configuration' will also
7548be different.
7549
7550It is generally recommended to use `system-configuration' rather
7551than `system-type'.
7552
7553See the file LINUX-GNU in this directory for more about this.
7554
7555** The functions shell-command and dired-call-process
7556now run file name handlers for default-directory, if it has them.
7557
7558** Undoing the deletion of text now restores the positions of markers
7559that pointed into or next to the deleted text.
7560
7561** Timers created with run-at-time now work internally to Emacs, and
7562no longer use a separate process. Therefore, they now work more
7563reliably and can be used for shorter time delays.
7564
7565The new function run-with-timer is a convenient way to set up a timer
7566to run a specified amount of time after the present. A call looks
7567like this:
7568
7569 (run-with-timer SECS REPEAT FUNCTION ARGS...)
7570
7571SECS says how many seconds should elapse before the timer happens.
7572It may be an integer or a floating point number. When the timer
7573becomes ripe, the action is to call FUNCTION with arguments ARGS.
7574
7575REPEAT gives the interval for repeating the timer (measured in
7576seconds). It may be an integer or a floating point number. nil or 0
7577means don't repeat at all--call FUNCTION just once.
7578
7579*** with-timeout provides an easy way to do something but give
7580up if too much time passes.
7581
7582 (with-timeout (SECONDS TIMEOUT-FORMS...) BODY...)
7583
7584This executes BODY, but gives up after SECONDS seconds.
7585If it gives up, it runs the TIMEOUT-FORMS and returns the value
7586of the last one of them. Normally it returns the value of the last
7587form in BODY.
7588
7589*** You can now arrange to call a function whenever Emacs is idle for
7590a certain length of time. To do this, call run-with-idle-timer. A
7591call looks like this:
7592
7593 (run-with-idle-timer SECS REPEAT FUNCTION ARGS...)
7594
7595SECS says how many seconds of idleness should elapse before the timer
7596runs. It may be an integer or a floating point number. When the
7597timer becomes ripe, the action is to call FUNCTION with arguments
7598ARGS.
7599
7600Emacs becomes idle whenever it finishes executing a keyboard or mouse
7601command. It remains idle until it receives another keyboard or mouse
7602command.
7603
7604REPEAT, if non-nil, means this timer should be activated again each
7605time Emacs becomes idle and remains idle for SECS seconds The timer
7606does not repeat if Emacs *remains* idle; it runs at most once after
7607each time Emacs becomes idle.
7608
7609If REPEAT is nil, the timer runs just once, the first time Emacs is
7610idle for SECS seconds.
7611
7612*** post-command-idle-hook is now obsolete; you shouldn't use it at
7613all, because it interferes with the idle timer mechanism. If your
7614programs use post-command-idle-hook, convert them to use idle timers
7615instead.
7616
7617*** y-or-n-p-with-timeout lets you ask a question but give up if
7618there is no answer within a certain time.
7619
7620 (y-or-n-p-with-timeout PROMPT SECONDS DEFAULT-VALUE)
7621
7622asks the question PROMPT (just like y-or-n-p). If the user answers
7623within SECONDS seconds, it returns the answer that the user gave.
7624Otherwise it gives up after SECONDS seconds, and returns DEFAULT-VALUE.
7625
7626** Minor change to `encode-time': you can now pass more than seven
7627arguments. If you do that, the first six arguments have the usual
7628meaning, the last argument is interpreted as the time zone, and the
7629arguments in between are ignored.
7630
7631This means that it works to use the list returned by `decode-time' as
7632the list of arguments for `encode-time'.
7633
7634** The default value of load-path now includes the directory
7635/usr/local/share/emacs/VERSION/site-lisp In addition to
7636/usr/local/share/emacs/site-lisp. You can use this new directory for
7637site-specific Lisp packages that belong with a particular Emacs
7638version.
7639
7640It is not unusual for a Lisp package that works well in one Emacs
7641version to cause trouble in another. Sometimes packages need updating
7642for incompatible changes; sometimes they look at internal data that
7643has changed; sometimes the package has been installed in Emacs itself
7644and the installed version should be used. Whatever the reason for the
7645problem, this new feature makes it easier to solve.
7646
7647** When your program contains a fixed file name (like .completions or
7648.abbrev.defs), the file name usually needs to be different on operating
7649systems with limited file name syntax.
7650
7651Now you can avoid ad-hoc conditionals by using the function
7652convert-standard-filename to convert the file name to a proper form
7653for each operating system. Here is an example of use, from the file
7654completions.el:
7655
7656(defvar save-completions-file-name
7657 (convert-standard-filename "~/.completions")
7658 "*The filename to save completions to.")
7659
7660This sets the variable save-completions-file-name to a value that
7661depends on the operating system, because the definition of
7662convert-standard-filename depends on the operating system. On
7663Unix-like systems, it returns the specified file name unchanged. On
7664MS-DOS, it adapts the name to fit the limitations of that system.
7665
7666** The interactive spec N now returns the numeric prefix argument
7667rather than the raw prefix argument. (It still reads a number using the
7668minibuffer if there is no prefix argument at all.)
7669
7670** When a process is deleted, this no longer disconnects the process
7671marker from its buffer position.
7672
7673** The variable garbage-collection-messages now controls whether
7674Emacs displays a message at the beginning and end of garbage collection.
7675The default is nil, meaning there are no messages.
7676
7677** The variable debug-ignored-errors specifies certain kinds of errors
7678that should not enter the debugger. Its value is a list of error
7679condition symbols and/or regular expressions. If the error has any
7680of the condition symbols listed, or if any of the regular expressions
7681matches the error message, then that error does not enter the debugger,
7682regardless of the value of debug-on-error.
7683
7684This variable is initialized to match certain common but uninteresting
7685errors that happen often during editing.
7686
7687** The new function error-message-string converts an error datum
7688into its error message. The error datum is what condition-case
7689puts into the variable, to describe the error that happened.
7690
7691** Anything that changes which buffer appears in a given window
7692now runs the window-scroll-functions for that window.
7693
7694** The new function get-buffer-window-list returns a list of windows displaying
7695a buffer. The function is called with the buffer (a buffer object or a buffer
7696name) and two optional arguments specifying the minibuffer windows and frames
7697to search. Therefore this function takes optional args like next-window etc.,
7698and not get-buffer-window.
7699
7700** buffer-substring now runs the hook buffer-access-fontify-functions,
7701calling each function with two arguments--the range of the buffer
7702being accessed. buffer-substring-no-properties does not call them.
7703
7704If you use this feature, you should set the variable
7705buffer-access-fontified-property to a non-nil symbol, which is a
7706property name. Then, if all the characters in the buffer range have a
7707non-nil value for that property, the buffer-access-fontify-functions
7708are not called. When called, these functions should put a non-nil
7709property on the text that they fontify, so that they won't get called
7710over and over for the same text.
7711
7712** Changes in lisp-mnt.el
7713
7714*** The lisp-mnt package can now recognize file headers that are written
7715in the formats used by the `what' command and the RCS `ident' command:
7716
7717;; @(#) HEADER: text
7718;; $HEADER: text $
7719
7720in addition to the normal
7721
7722;; HEADER: text
7723
7724*** The commands lm-verify and lm-synopsis are now interactive. lm-verify
7725checks that the library file has proper sections and headers, and
7726lm-synopsis extracts first line "synopsis'"information.
7727\f
7728* For older news, see the file ONEWS.
7729
7730----------------------------------------------------------------------
7731Copyright information:
7732
404fa7d6 7733Copyright (C) 1996, 1997, 1998, 1999, 2000 Free Software Foundation, Inc.
a933dad1
DL
7734
7735 Permission is granted to anyone to make or distribute verbatim copies
7736 of this document as received, in any medium, provided that the
7737 copyright notice and this permission notice are preserved,
7738 thus giving the recipient permission to redistribute in turn.
7739
7740 Permission is granted to distribute modified versions
7741 of this document, or of portions of it,
7742 under the above conditions, provided also that they
7743 carry prominent notices stating who last changed them.
7744\f
7745Local variables:
7746mode: outline
7747paragraph-separate: "[ \f]*$"
7748end: