(tags-case-fold-search): New user-option.
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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*** RET is now bound in the Rmail summary to rmail-summary-goto-msg,
476like `j'.
477
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478*** There is a new user option `rmail-digest-end-regexps' that
479specifies the regular expressions to detect the line that ends a
2d5e9b54 480digest message.
e26cec67 481
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482** Changes to TeX mode
483
484The default mode has been changed from `plain-tex-mode' to
485`latex-mode'.
486
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487** Changes to RefTeX mode
488
489*** RefTeX has new support for index generation. Index entries can be
490 created with `C-c <', with completion available on index keys.
491 Pressing `C-c /' indexes the word at the cursor with a default
492 macro. `C-c >' compiles all index entries into an alphabetically
493 sorted *Index* buffer which looks like the final index. Entries
494 can be edited from that buffer.
495
496*** Label and citation key selection now allow to select several
497 items and reference them together (use `m' to mark items, `a' or
498 `A' to use all marked entries).
499
500*** reftex.el has been split into a number of smaller files to reduce
501 memory use when only a part of RefTeX is being used.
502
503*** a new command `reftex-view-crossref-from-bibtex' (bound to `C-c &'
504 in BibTeX-mode) can be called in a BibTeX database buffer in order
505 to show locations in LaTeX documents where a particular entry has
506 been cited.
507
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508** Emacs Lisp mode now allows multiple levels of outline headings.
509The level of a heading is determined from the number of leading
510semicolons in a heading line. Toplevel forms starting with a `('
511in column 1 are always made leaves.
512
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513** The M-x time-stamp command (most commonly used on write-file-hooks)
514has the following new features:
515
516*** The patterns for finding the time stamp and for updating a pattern
517may match text spanning multiple lines. For example, some people like
518to have the filename and date on separate lines. The new variable
519time-stamp-inserts-lines controls the matching for multi-line patterns.
520
521*** More than one time stamp can be updated in the same file. This
522feature is useful if you need separate time stamps in a program source
523file to both include in formatted documentation and insert in the
524compiled binary. The same time-stamp will be written at each matching
525pattern. The variable time-stamp-count enables this new feature; it
526defaults to 1.
527
528** Tooltips.
529
530Tooltips are small X windows displaying a help string at the current
531mouse position. To use them, use the Lisp package `tooltip' which you
532can access via the user option `tooltip-mode'.
533
534Tooltips also provides support for GUD debugging. If activated,
535variable values can be displayed in tooltips by pointing at them with
536the mouse in source buffers. You can customize various aspects of the
537tooltip display in the group `tooltip'.
538
539** Customize changes
540
541*** Customize now supports comments about customized items. Use the
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542`State' menu to add comments. Note that customization comments will
543cause the customizations to fail in earlier versions of Emacs.
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544
545*** The new option `custom-buffer-done-function' says whether to kill
546Custom buffers when you've done with them or just bury them (the
547default).
548
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549*** The keyword :set-after in defcustom allows to specify dependencies
550between custom options. Example:
551
552 (defcustom default-input-method nil
553 "*Default input method for multilingual text (a string).
554 This is the input method activated automatically by the command
555 `toggle-input-method' (\\[toggle-input-method])."
556 :group 'mule
557 :type '(choice (const nil) string)
558 :set-after '(current-language-environment))
559
560This specifies that default-input-method should be set after
561current-language-environment even if default-input-method appears
562first in a custom-set-variables statement.
563
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564** New features in evaluation commands
565
566The commands to evaluate Lisp expressions, such as C-M-x in Lisp
567modes, C-j in Lisp Interaction mode, and M-:, now bind the variables
568print-level, print-length, and debug-on-error based on the
569customizable variables eval-expression-print-level,
570eval-expression-print-length, and eval-expression-debug-on-error.
571
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572** Dired changes
573
574*** New variable `dired-recursive-deletes' determines if the delete
575command will delete non-empty directories recursively. The default
576is, delete only empty directories.
577
578*** New variable `dired-recursive-copies' determines if the copy
579command will copy directories recursively. The default is, do not
580copy directories recursively.
581
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582*** In command `dired-do-shell-command' (usually bound to `!') a `?'
583in the shell command has a special meaning similar to `*', but with
584the difference that the command will be run on each file individually.
585
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586** The variable mail-specify-envelope-from controls whether to
587use the -f option when sending mail.
588
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589** CC mode changes.
590
591Note: This release contains changes that might not be compatible with
592current user setups (although it's believed that these
593incompatibilities will only show in very uncommon circumstances).
594However, since the impact is uncertain, these changes may be rolled
595back depending on user feedback. Therefore there's no forward
596compatibility guarantee wrt the new features introduced in this
597release.
598
599*** New initialization procedure for the style system.
600When the initial style for a buffer is determined by CC Mode (from the
601variable c-default-style), the global values of style variables now
602take precedence over the values specified by the chosen style. This
603is different than the old behavior: previously, the style-specific
604settings would override the global settings. This change makes it
605possible to do simple configuration in the intuitive way with
606Customize or with setq lines in one's .emacs file.
607
608By default, the global value of every style variable is the new
609special symbol set-from-style, which causes the value to be taken from
610the style system. This means that in effect, only an explicit setting
611of a style variable will cause the "overriding" behavior described
612above.
613
614Also note that global settings override style-specific settings *only*
615when the initial style of a buffer is chosen by a CC Mode major mode
616function. When a style is chosen in other ways --- for example, by a
617call like (c-set-style "gnu") in a hook, or via M-x c-set-style ---
618then the style-specific values take precedence over any global style
619values. In Lisp terms, global values override style-specific values
620only when the new second argument to c-set-style is non-nil; see the
621function documentation for more info.
622
623The purpose of these changes is to make it easier for users,
624especially novice users, to do simple customizations with Customize or
625with setq in their .emacs files. On the other hand, the new system is
626intended to be compatible with advanced users' customizations as well,
627such as those that choose styles in hooks or whatnot. This new system
628is believed to be almost entirely compatible with current
629configurations, in spite of the changed precedence between style and
630global variable settings when a buffer's default style is set.
631
632(Thanks to Eric Eide for clarifying this explanation a bit.)
633
634**** c-offsets-alist is now a customizable variable.
635This became possible as a result of the new initialization behavior.
636
637This variable is treated slightly differently from the other style
638variables; instead of using the symbol set-from-style, it will be
639completed with the syntactic symbols it doesn't already contain when
640the style is first initialized. This means it now defaults to the
641empty list to make all syntactic elements get their values from the
642style system.
643
644**** Compatibility variable to restore the old behavior.
645In case your configuration doesn't work with this change, you can set
646c-old-style-variable-behavior to non-nil to get the old behavior back
647as far as possible.
648
649*** Improvements to line breaking and text filling.
650CC Mode now handles this more intelligently and seamlessly wrt the
651surrounding code, especially inside comments. For details see the new
652chapter about this in the manual.
653
654**** New variable to recognize comment line prefix decorations.
655The variable c-comment-prefix-regexp has been added to properly
656recognize the line prefix in both block and line comments. It's
657primarily used to initialize the various paragraph recognition and
658adaptive filling variables that the text handling functions uses.
659
660**** New variable c-block-comment-prefix.
661This is a generalization of the now obsolete variable
662c-comment-continuation-stars to handle arbitrary strings.
663
664**** CC Mode now uses adaptive fill mode.
665This to make it adapt better to the paragraph style inside comments.
666
667It's also possible to use other adaptive filling packages inside CC
668Mode, notably Kyle E. Jones' Filladapt mode (http://wonderworks.com/).
669A new convenience function c-setup-filladapt sets up Filladapt for use
670inside CC Mode.
671
672Note though that the 2.12 version of Filladapt lacks a feature that
673causes it to work suboptimally when c-comment-prefix-regexp can match
674the empty string (which it commonly does). A patch for that is
675available from the CC Mode web site (http://www.python.org/emacs/
676cc-mode/).
677
678**** It's now possible to selectively turn off auto filling.
679The variable c-ignore-auto-fill is used to ignore auto fill mode in
680specific contexts, e.g. in preprocessor directives and in string
681literals.
682
683**** New context sensitive line break function c-context-line-break.
684It works like newline-and-indent in normal code, and adapts the line
685prefix according to the comment style when used inside comments. If
686you're normally using newline-and-indent, you might want to switch to
687this function.
688
689*** Fixes to IDL mode.
690It now does a better job in recognizing only the constructs relevant
691to IDL. E.g. it no longer matches "class" as the beginning of a
692struct block, but it does match the CORBA 2.3 "valuetype" keyword.
693Thanks to Eric Eide.
694
695*** Improvements to the Whitesmith style.
696It now keeps the style consistently on all levels and both when
697opening braces hangs and when they don't.
698
699**** New lineup function c-lineup-whitesmith-in-block.
700
701*** New lineup functions c-lineup-template-args and c-indent-multi-line-block.
702See their docstrings for details. c-lineup-template-args does a
703better job of tracking the brackets used as parens in C++ templates,
704and is used by default to line up continued template arguments.
705
706*** c-lineup-comment now preserves alignment with a comment on the
707previous line. It used to instead preserve comments that started in
708the column specified by comment-column.
709
710*** c-lineup-C-comments handles "free form" text comments.
711In comments with a long delimiter line at the start, the indentation
712is kept unchanged for lines that start with an empty comment line
713prefix. This is intended for the type of large block comments that
714contain documentation with its own formatting. In these you normally
715don't want CC Mode to change the indentation.
716
717*** The `c' syntactic symbol is now relative to the comment start
718instead of the previous line, to make integers usable as lineup
719arguments.
720
721*** All lineup functions have gotten docstrings.
722
723*** More preprocessor directive movement functions.
724c-down-conditional does the reverse of c-up-conditional.
725c-up-conditional-with-else and c-down-conditional-with-else are
726variants of these that also stops at "#else" lines (suggested by Don
727Provan).
728
729*** Minor improvements to many movement functions in tricky situations.
730
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731** Isearch changes
732
733*** In Isearch mode, mouse-2 in the echo area now yanks the current
a933dad1
DL
734selection into the search string rather than giving an error.
735
87be76f6
GM
736*** There is a new lazy highlighting feature in incremental search.
737
d35fce81 738Lazy highlighting is switched on/off by customizing variable
87be76f6
GM
739`isearch-lazy-highlight'. When active, all matches for the current
740search string are highlighted. The current match is highlighted as
741before using face `isearch' or `region'. All other matches are
742highlighted using face `isearch-lazy-highlight-face' which defaults to
743`secondary-selection'.
744
745The extra highlighting makes it easier to anticipate where the cursor
746will end up each time you press C-s or C-r to repeat a pending search.
747Highlighting of these additional matches happens in a deferred fashion
748using "idle timers," so the cycles needed do not rob isearch of its
749usual snappy response.
750
751If `isearch-lazy-highlight-cleanup' is set to t, highlights for
752matches are automatically cleared when you end the search. If it is
753set to nil, you can remove the highlights manually with `M-x
754isearch-lazy-highlight-cleanup'.
755
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756** Changes in sort.el
757
758The function sort-numeric-fields interprets numbers starting with `0'
12c25bdc 759as octal and numbers starting with `0x' or `0X' as hexadecimal. The
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GM
760new user-option sort-numberic-base can be used to specify a default
761numeric base.
87be76f6 762
d7b511c4
GM
763** Changes to Ange-ftp
764
765*** Ange-ftp allows you to specify of a port number in remote file
d67f47e4
DL
766names cleanly. It is appended to the host name, separated by a hash
767sign, e.g. `/foo@bar.org#666:mumble'. (This syntax comes from EFS.)
768
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GM
769*** If the new user-option `ange-ftp-try-passive-mode' is set, passive
770ftp mode will be used if the ftp client supports that.
771
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GM
772** Shell script mode changes.
773
774Shell script mode (sh-script) can now indent scripts for shells
775derived from sh and rc. The indentation style is customizeable, and
776sh-script can attempt to "learn" the current buffer's style.
777
79214ddf
FP
778** Etags changes.
779
780*** In DOS, etags looks for file.cgz if it cannot find file.c.
781
aca0be23 782*** New option --ignore-case-regex is an alternative to --regex. It is now
8dc78b52
FP
783possible to bind a regexp to a language, by prepending the regexp with
784{lang}, where lang is one of the languages that `etags --help' prints out.
785This feature is useful especially for regex files, where each line contains
786a regular expression. The manual contains details.
aca0be23 787
79214ddf
FP
788*** In C and derived languages, etags creates tags for function
789declarations when given the --declarations option.
790
791*** In C++, tags are created for "operator". The tags have the form
aca0be23 792"operator+", without spaces between the keyword and the operator.
79214ddf
FP
793
794*** New language Ada: tags are functions, procedures, packages, tasks, and
795types.
796
797*** In Fortran, procedure is no more tagged.
798
799*** In Java, tags are created for "interface".
800
801*** In Lisp, "(defstruct (foo", "(defun (operator" and similar constructs
802are now tagged.
803
804*** In Perl, the --globals option tags global variables. my and local
805variables are tagged.
806
807*** New language Python: def and class at the beginning of a line are tags.
808
8dc78b52
FP
809*** .ss files are Scheme files, .pdb is Postscript with C syntax, .psw is
810for PSWrap.
79214ddf 811
f6737cde
GM
812** Changes in etags.el
813
814*** You can display additional output with M-x tags-apropos by setting
815the new variable tags-apropos-additional-actions.
816
817If non-nil, the variable's value should be a list of triples (TITLE
818FUNCTION TO-SEARCH). For each triple, M-x tags-apropos processes
819TO-SEARCH and lists tags from it. TO-SEARCH should be an alist,
820obarray, or symbol. If it is a symbol, the symbol's value is used.
821
822TITLE is a string to use to label the list of tags from TO-SEARCH.
823
824FUNCTION is a function to call when an entry is selected in the Tags
825List buffer. It is called with one argument, the selected symbol.
826
827A useful example value for this variable might be something like:
828
829 '(("Emacs Lisp" Info-goto-emacs-command-node obarray)
830 ("Common Lisp" common-lisp-hyperspec common-lisp-hyperspec-obarray)
831 ("SCWM" scwm-documentation scwm-obarray))
832
833*** The face tags-tag-face can be used to customize the appearance
834of tags in the output of M-x tags-apropos.
835
836*** Setting tags-apropos-verbose to a non-nil value displays the
837names of tags files in the *Tags List* buffer.
838
fbc164de
PE
839** Emacs now attempts to determine the initial language environment
840and preferred and locale coding systems systematically from the
841LC_ALL, LC_CTYPE, and LANG environment variables during startup.
842
59c1bf85
DL
843** New language environments `Latin-8' and `Latin-9'.
844These correspond respectively to the ISO character sets 8859-14
845(Celtic) and 8859-15 (updated Latin-1, with the Euro sign). There is
846currently no specific input method support for them.
847
e33b0397
DL
848** Fortran mode has a new command `fortran-strip-sqeuence-nos' to
849remove text past column 72. The syntax class of `\' in Fortran is now
850appropriate for C-style escape sequences in strings.
851
852** SGML mode's default `sgml-validate-command' is now `nsgmls'.
853
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DL
854** A new command `view-emacs-problems' (C-h P) displays the PROBLEMS file.
855
a933dad1
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856** New modes and packages
857
5e5dff44
GM
858*** The new command M-x re-builder offers a convenient interface for
859authoring regular expressions with immediate visual feedback.
860
861The buffer from which the command was called becomes the target for
862the regexp editor popping up in a separate window. Matching text in
863the target buffer is immediately color marked during the editing.
864Each sub-expression of the regexp will show up in a different face so
865even complex regexps can be edited and verified on target data in a
866single step.
867
868On displays not supporting faces the matches instead blink like
869matching parens to make them stand out. On such a setup you will
870probably also want to use the sub-expression mode when the regexp
871contains such to get feedback about their respective limits.
872
f7136ee8
GM
873*** glasses-mode is a minor mode that makes
874unreadableIdentifiersLikeThis readable. It works as glasses, without
875actually modifying content of a buffer.
876
bbd9b566
GM
877*** The package ebnf2ps translates an EBNF to a syntactic chart in
878PostScript.
879
880Currently accepts ad-hoc EBNF, ISO EBNF and Bison/Yacc.
881
882The ad-hoc default EBNF syntax has the following elements:
883
884 ; comment (until end of line)
885 A non-terminal
886 "C" terminal
887 ?C? special
888 $A default non-terminal
889 $"C" default terminal
890 $?C? default special
891 A = B. production (A is the header and B the body)
892 C D sequence (C occurs before D)
893 C | D alternative (C or D occurs)
894 A - B exception (A excluding B, B without any non-terminal)
895 n * A repetition (A repeats n (integer) times)
896 (C) group (expression C is grouped together)
897 [C] optional (C may or not occurs)
898 C+ one or more occurrences of C
899 {C}+ one or more occurrences of C
900 {C}* zero or more occurrences of C
901 {C} zero or more occurrences of C
902 C / D equivalent to: C {D C}*
903 {C || D}+ equivalent to: C {D C}*
904 {C || D}* equivalent to: [C {D C}*]
905 {C || D} equivalent to: [C {D C}*]
906
907Please, see ebnf2ps documentation for EBNF syntax and how to use it.
908
99453a38
GM
909*** The package align.el will align columns within a region, using M-x
910align. Its mode-specific rules, based on regular expressions,
911determine where the columns should be split. In C and C++, for
912example, it will align variable names in declaration lists, or the
913equal signs of assignments.
914
559cee90
DL
915*** `paragraph-indent-minor-mode' is a new minor mode supporting
916paragraphs in the same style as `paragraph-indent-text-mode'.
917
6448a6b3
GM
918*** bs.el is a new package for buffer selection similar to
919list-buffers or electric-buffer-list. Use M-x bs-show to display a
920buffer menu with this package. You can use M-x bs-customize to
921customize the package.
922
249652b1
GM
923*** calculator.el is a small calculator package that is intended to
924replace desktop calculators such as xcalc and calc.exe. Actually, it
925is not too small - it has more features than most desktop calculators,
926and can be customized easily to get many more functions. It should
927not be confused with "calc" which is a much bigger mathematical tool
928which answers different needs.
929
3476b54a
GM
930*** The minor modes cwarn-mode and global-cwarn-mode highlights
931suspicious C and C++ constructions. Currently, assignments inside
932expressions, semicolon following `if', `for' and `while' (except, of
933course, after a `do .. while' statement), and C++ functions with
934reference parameters are recognized. The modes require font-lock mode
935to be enabled.
936
8964fec7
SM
937*** smerge-mode.el provides `smerge-mode', a simple minor-mode for files
938containing diff3-style conflict markers, such as generated by RCS.
939
a933dad1
DL
940*** 5x5.el is a simple puzzle game.
941
942*** hl-line.el provides a minor mode to highlight the current line.
943
944*** ansi-color.el translates ANSI terminal escapes into text-properties.
945
946*** delphi.el provides a major mode for editing the Delphi (Object
947Pascal) language.
948
949*** quickurl.el provides a simple method of inserting a URL based on
950the text at point.
951
952*** sql.el provides an interface to SQL data bases.
953
8d54eb69
DL
954*** fortune.el uses the fortune program to create mail/news signatures.
955
a933dad1
DL
956*** whitespace.el ???
957
ebcfda83
GM
958*** PostScript mode (ps-mode) is a new major mode for editing PostScript
959files. It offers: interaction with a PostScript interpreter, including
960(very basic) error handling; fontification, easily customizable for
961interpreter messages; auto-indentation; insertion of EPSF templates and
962often used code snippets; viewing of BoundingBox; commenting out /
963uncommenting regions; conversion of 8bit characters to PostScript octal
964codes. All functionality is accessible through a menu.
965
966*** delim-col helps to prettify columns in a text region or rectangle.
967
968Here is an example of columns:
969
970horse apple bus
971dog pineapple car EXTRA
972porcupine strawberry airplane
973
974Doing the following settings:
975
976 (setq delimit-columns-str-before "[ ")
977 (setq delimit-columns-str-after " ]")
978 (setq delimit-columns-str-separator ", ")
979 (setq delimit-columns-separator "\t")
980
981
982Selecting the lines above and typing:
983
984 M-x delimit-columns-region
985
986It results:
987
988[ horse , apple , bus , ]
989[ dog , pineapple , car , EXTRA ]
990[ porcupine, strawberry, airplane, ]
991
992delim-col has the following options:
993
994 delimit-columns-str-before Specify a string to be inserted
995 before all columns.
996
997 delimit-columns-str-separator Specify a string to be inserted
998 between each column.
999
1000 delimit-columns-str-after Specify a string to be inserted
1001 after all columns.
1002
1003 delimit-columns-separator Specify a regexp which separates
1004 each column.
1005
1006delim-col has the following commands:
1007
1008 delimit-columns-region Prettify all columns in a text region.
1009 delimit-columns-rectangle Prettify all columns in a text rectangle.
1010
f507826c
GM
1011*** The package recentf.el maintains a menu for visiting files that
1012were operated on recently. When enabled, a new "Open Recent" submenu
1013is displayed in the "Files" menu.
1014
1015The recent files list is automatically saved across Emacs sessions.
1016
1017To enable/disable recentf use M-x recentf-mode.
1018
1019To enable recentf at Emacs startup use
1020M-x customize-variable RET recentf-mode RET.
1021
1022To change the number of recent files displayed and others options use
1023M-x customize-group RET recentf RET.
1024
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DL
1025*** elide-head.el provides a mechanism for eliding boilerplate header
1026text.
1027
36e24b82 1028*** footnote.el provides `footnote-mode', a minor mode supporting use
91735437
DL
1029of footnotes. It is intended for use with Message mode, but isn't
1030specific to Message mode.
1031
36e24b82
DL
1032*** diff-mode.el provides `diff-mode', a major mode for
1033viewing/editing context diffs (patches). It is selected for files
1034with extension `.diff', `.diffs', `.patch' and `.rej'.
1035
aaa659ef
DL
1036*** EUDC, the Emacs Unified Directory Client, provides a common user
1037interface to access directory servers using different directory
1038protocols. It has a separate manual.
1039
eee54b0e
DL
1040*** autoconf.el provides a major mode for editing configure.in files
1041for Autoconf, selected automatically.
1042
aaa659ef
DL
1043*** windmove.el
1044
a933dad1
DL
1045** Withdrawn packages
1046
1047*** mldrag.el has been removed. mouse.el provides the same
1048functionality with aliases for the mldrag functions.
25a81338 1049
3261c1d8
DL
1050*** eval-reg.el has been obsoleted by changes to edebug.el and removed.
1051
1052*** ph.el has been obsoleted by EUDC and removed.
a933dad1
DL
1053\f
1054* Lisp changes in Emacs 21.1 (see following page for display-related features)
1055
1056Note that +++ before an item means the Lisp manual has been updated.
1057--- means that I have decided it does not need to be in the Lisp manual.
1058When you add a new item, please add it without either +++ or ---
1059so I will know I still need to look at it -- rms.
1060
d7b511c4
GM
1061** The new function `string-to-syntax' can be used to translate syntax
1062specificationa in string form as accepted my `modify-syntax-entry' to
1063the cons-cell form that is used for the values of the `syntax-table'
1064text property, and in `font-lock-syntactic-keywords'.
1065
1066Example:
1067
1068 (string-to-syntax "()")
1069 => (4 . 41)
1070
1fa28578
GM
1071** Emacs' reader supports CL read syntax for integers in bases
1072other than 10.
1073
1074*** `#BINTEGER' or `#bINTEGER' reads INTEGER in binary (radix 2).
1075INTEGER optionally contains a sign.
1076
1077 #b1111
1078 => 15
1079 #b-1111
1080 => -15
1081
1082*** `#OINTEGER' or `#oINTEGER' reads INTEGER in octal (radix 8).
1083
1084 #o666
1085 => 438
1086
1087*** `#XINTEGER' or `#xINTEGER' reads INTEGER in hexadecimal (radix 16).
1088
1089 #xbeef
1090 => 48815
1091
1092*** `#RADIXrINTEGER' reads INTEGER in radix RADIX, 2 <= RADIX <= 36.
1093
1094 #2R-111
1095 => -7
1096 #25rah
1097 => 267
1098
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GM
1099** The function documentation-property now evaluates the value of
1100the given property to obtain a a string if it doesn't refer to etc/DOC
1101and isn't a string.
1102
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DL
1103+++
1104** The last argument of `define-key-after' defaults to t for convenience.
1105
73825616 1106** The new function `replace-regexp-in-string' replaces all matches
16ce590d
DL
1107for a regexp in a string.
1108
1109** `mouse-position' now runs the abnormal hook
1110`mouse-position-function'.
1111
723e779c
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1112** The function string-to-number now returns a float for numbers
1113that don't fit into a Lisp integer.
1114
d1e103b2
GM
1115** The variable keyword-symbols-constants-flag has been removed.
1116Keywords are now always considered constants.
1117
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DL
1118+++
1119** The new function `delete-and-extract-region' deletes text and
1120returns it.
1121
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GM
1122** The function `clear-this-command-keys' now also clears the vector
1123returned by function `recent-keys'.
1124
02b14400
RS
1125+++
1126** Variables `beginning-of-defun-function' and `end-of-defun-function'
1127can be used to define handlers for the functions that find defuns.
1128Major modes can define these locally instead of rebinding M-C-a
1129etc. if the normal conventions for defuns are not appropriate for the
1130mode.
404fa7d6 1131
02b14400 1132+++
8964fec7
SM
1133** easy-mmode-define-minor-mode now takes an additional BODY argument
1134and is renamed `define-minor-mode'.
1135
02b14400
RS
1136+++
1137** If an abbrev has a hook function which is a symbol, and that symbol
1138has a non-nil `no-self-insert' property, the return value of the hook
1139function specifies whether an expansion has been done or not. If it
1140returns nil, abbrev-expand also returns nil, meaning "no expansion has
1141been performed."
1142
1143When abbrev expansion is done by typing a self-inserting character,
1144and the abbrev has a hook with the `no-self-insert' property, and the
1145hook function returns non-nil meaning expansion has been done,
1146then the self-inserting character is not inserted.
ef961722 1147
02b14400 1148+++
81da8b32
GM
1149** The function `intern-soft' now accepts a symbol as first argument.
1150In this case, that exact symbol is looked up in the specified obarray,
1151and the function's value is nil if it is not found.
1152
02b14400 1153+++
9e207b90
GM
1154** The new macro `with-syntax-table' can be used to evaluate forms
1155with the syntax table of the current buffer temporarily set to a
1156specified table.
1157
1158 (with-syntax-table TABLE &rest BODY)
1159
1160Evaluate BODY with syntax table of current buffer set to a copy of
03d9c64c
GM
1161TABLE. The current syntax table is saved, BODY is evaluated, and the
1162saved table is restored, even in case of an abnormal exit. Value is
1163what BODY returns.
9e207b90 1164
02b14400 1165+++
d7f89643 1166** Regular expressions now support intervals \{n,m\} as well as
95cd4c40 1167Perl's shy-groups \(?:...\) and non-greedy *? +? and ?? operators.
8964fec7 1168
02b14400 1169+++
dde9e75a
GM
1170** The optional argument BUFFER of function file-local-copy has been
1171removed since it wasn't used by anything.
1172
02b14400 1173+++
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GM
1174** The file name argument of function `file-locked-p' is now required
1175instead of being optional.
1176
02b14400 1177+++
d20679eb
GM
1178** The new built-in error `text-read-only' is signaled when trying to
1179modify read-only text.
1180
02b14400 1181+++
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PE
1182** New functions and variables for locales.
1183
1184The new variable `locale-coding-system' specifies how to encode and
1185decode strings passed to low-level message functions like strerror and
b718982a
PE
1186time functions like strftime. The new variables
1187`system-messages-locale' and `system-time-locale' give the system
1188locales to be used when invoking these two types of functions.
fbc164de
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1189
1190The new function `set-locale-environment' sets the language
1191environment, preferred coding system, and locale coding system from
1192the system locale as specified by the LC_ALL, LC_CTYPE, and LANG
b718982a
PE
1193environment variables. Normally, it is invoked during startup and need
1194not be invoked thereafter. It uses the new variables
1195`locale-language-names', `locale-charset-language-names', and
1196`locale-preferred-coding-systems' to make its decisions.
fbc164de 1197
02b14400 1198+++
863476d1
SM
1199** syntax tables now understand nested comments.
1200To declare a comment syntax as allowing nesting, just add an `n'
1201modifier to either of the characters of the comment end and the comment
1202start sequences.
1203
02b14400 1204+++
ef6d912c
GM
1205** The function `pixmap-spec-p' has been renamed `bitmap-spec-p'
1206because `bitmap' is more in line with the usual X terminology.
1207
02b14400 1208+++
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DL
1209** New function `propertize'
1210
1211The new function `propertize' can be used to conveniently construct
1212strings with text properties.
1213
1214- Function: propertize STRING &rest PROPERTIES
1215
1216Value is a copy of STRING with text properties assigned as specified
1217by PROPERTIES. PROPERTIES is a sequence of pairs PROPERTY VALUE, with
1218PROPERTY being the name of a text property and VALUE being the
1219specified value of that property. Example:
1220
1221 (propertize "foo" 'face 'bold 'read-only t)
1222
1223+++
1224** push and pop macros.
1225
02b14400
RS
1226Simple versions of the push and pop macros of Common Lisp
1227are now defined in Emacs Lisp. These macros allow only symbols
a933dad1
DL
1228as the place that holds the list to be changed.
1229
1230(push NEWELT LISTNAME) add NEWELT to the front of LISTNAME's value.
1231(pop LISTNAME) return first elt of LISTNAME, and remove it
1232 (thus altering the value of LISTNAME).
1233
02b14400
RS
1234** New dolist and dotimes macros.
1235
6c7fd5aa
RS
1236Simple versions of the dolist and dotimes macros of Common Lisp
1237are now defined in Emacs Lisp.
02b14400
RS
1238
1239(dolist (VAR LIST [RESULT]) BODY...)
1240 Execute body once for each element of LIST,
1241 using the variable VAR to hold the current element.
1242 Then return the value of RESULT, or nil if RESULT is omitted.
1243
1244(dotimes (VAR COUNT [RESULT]) BODY...)
1245 Execute BODY with VAR bound to successive integers running from 0,
1246 inclusive, to COUNT, exclusive.
1247 Then return the value of RESULT, or nil if RESULT is omitted.
1248
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1249+++
1250** Regular expressions now support Posix character classes such
1251as [:alpha:], [:space:] and so on.
1252
1253[:digit:] matches 0 through 9
1254[:cntrl:] matches ASCII control characters
1255[:xdigit:] matches 0 through 9, a through f and A through F.
1256[:blank:] matches space and tab only
1257[:graph:] matches graphic characters--everything except ASCII control chars,
1258 space, and DEL.
1259[:print:] matches printing characters--everything except ASCII control chars
1260 and DEL.
1261[:alnum:] matches letters and digits.
1262 (But at present, for multibyte characters,
1263 it matches anything that has word syntax.)
1264[:alpha:] matches letters.
1265 (But at present, for multibyte characters,
1266 it matches anything that has word syntax.)
1267[:ascii:] matches ASCII (unibyte) characters.
1268[:nonascii:] matches non-ASCII (multibyte) characters.
1269[:lower:] matches anything lower-case.
1270[:punct:] matches punctuation.
1271 (But at present, for multibyte characters,
1272 it matches anything that has non-word syntax.)
1273[:space:] matches anything that has whitespace syntax.
1274[:upper:] matches anything upper-case.
1275[:word:] matches anything that has word syntax.
1276
1277+++
1278** Emacs now has built-in hash tables.
1279
1280The following functions are defined for hash tables:
1281
1282- Function: make-hash-table ARGS
1283
1284The argument list ARGS consists of keyword/argument pairs. All arguments
1285are optional. The following arguments are defined:
1286
1287:test TEST
1288
1289TEST must be a symbol specifying how to compare keys. Default is `eql'.
1290Predefined are `eq', `eql' and `equal'. If TEST is not predefined,
1291it must have been defined with `define-hash-table-test'.
1292
1293:size SIZE
1294
1295SIZE must be an integer > 0 giving a hint to the implementation how
1296many elements will be put in the hash table. Default size is 65.
1297
1298:rehash-size REHASH-SIZE
1299
1300REHASH-SIZE specifies by how much to grow a hash table once it becomes
1301full. If REHASH-SIZE is an integer, add that to the hash table's old
1302size to get the new size. Otherwise, REHASH-SIZE must be a float >
13031.0, and the new size is computed by multiplying REHASH-SIZE with the
1304old size. Default rehash size is 1.5.
1305
1306:rehash-threshold THRESHOLD
1307
1308THRESHOLD must be a float > 0 and <= 1.0 specifying when to resize the
1309hash table. It is resized when the ratio of (number of entries) /
1310(size of hash table) is >= THRESHOLD. Default threshold is 0.8.
1311
1312:weakness WEAK
1313
1314WEAK must be either nil, one of the symbols `key, `value', or t.
1315Entries are removed from weak tables during garbage collection if
1316their key and/or value are not referenced elsewhere outside of the
1317hash table. Default are non-weak hash tables.
1318
1319- Function: makehash &optional TEST
1320
1321Similar to make-hash-table, but only TEST can be specified.
1322
1323- Function: hash-table-p TABLE
1324
1325Returns non-nil if TABLE is a hash table object.
1326
1327- Function: copy-hash-table TABLE
1328
1329Returns a copy of TABLE. Only the table itself is copied, keys and
1330values are shared.
1331
1332- Function: hash-table-count TABLE
1333
1334Returns the number of entries in TABLE.
1335
1336- Function: hash-table-rehash-size TABLE
1337
1338Returns the rehash size of TABLE.
1339
1340- Function: hash-table-rehash-threshold TABLE
1341
1342Returns the rehash threshold of TABLE.
1343
1344- Function: hash-table-rehash-size TABLE
1345
1346Returns the size of TABLE.
1347
1348- Function: hash-table-rehash-test TABLE
1349
1350Returns the test TABLE uses to compare keys.
1351
1352- Function: hash-table-weakness TABLE
1353
1354Returns the weakness specified for TABLE.
1355
1356- Function: clrhash TABLE
1357
1358Clear TABLE.
1359
1360- Function: gethash KEY TABLE &optional DEFAULT
1361
1362Look up KEY in TABLE and return its associated VALUE or DEFAULT if
1363not found.
1364
79214ddf 1365- Function: puthash KEY VALUE TABLE
a933dad1
DL
1366
1367Associate KEY with VALUE in TABLE. If KEY is already associated with
1368another value, replace the old value with VALUE.
1369
1370- Function: remhash KEY TABLE
1371
1372Remove KEY from TABLE if it is there.
1373
1374- Function: maphash FUNCTION TABLE
1375
1376Call FUNCTION for all elements in TABLE. FUNCTION must take two
1377arguments KEY and VALUE.
1378
1379- Function: sxhash OBJ
1380
1381Return a hash code for Lisp object OBJ.
1382
1383- Function: define-hash-table-test NAME TEST-FN HASH-FN
1384
1385Define a new hash table test named NAME. If NAME is specified as
1386a test in `make-hash-table', the table created will use TEST-FN for
79214ddf 1387comparing keys, and HASH-FN to compute hash codes for keys. Test
a933dad1
DL
1388and hash function are stored as symbol property `hash-table-test'
1389of NAME with a value of (TEST-FN HASH-FN).
1390
1391TEST-FN must take two arguments and return non-nil if they are the same.
1392
1393HASH-FN must take one argument and return an integer that is the hash
1394code of the argument. The function should use the whole range of
1395integer values for hash code computation, including negative integers.
1396
1397Example: The following creates a hash table whose keys are supposed to
1398be strings that are compared case-insensitively.
1399
1400 (defun case-fold-string= (a b)
1401 (compare-strings a nil nil b nil nil t))
1402
1403 (defun case-fold-string-hash (a)
1404 (sxhash (upcase a)))
1405
79214ddf 1406 (define-hash-table-test 'case-fold 'case-fold-string=
a933dad1
DL
1407 'case-fold-string-hash))
1408
1409 (make-hash-table :test 'case-fold)
1410
1411+++
1412** The Lisp reader handles circular structure.
1413
1414It now works to use the #N= and #N# constructs to represent
1415circular structures. For example, #1=(a . #1#) represents
1416a cons cell which is its own cdr.
1417
1418+++
1419** The Lisp printer handles circular structure.
1420
1421If you bind print-circle to a non-nil value, the Lisp printer outputs
1422#N= and #N# constructs to represent circular and shared structure.
1423
a933dad1
DL
1424+++
1425** If the second argument to `move-to-column' is anything but nil or
1426t, that means replace a tab with spaces if necessary to reach the
1427specified column, but do not add spaces at the end of the line if it
1428is too short to reach that column.
1429
1430+++
1431** perform-replace has a new feature: the REPLACEMENTS argument may
1432now be a cons cell (FUNCTION . DATA). This means to call FUNCTION
1433after each match to get the replacement text. FUNCTION is called with
1434two arguments: DATA, and the number of replacements already made.
1435
1436If the FROM-STRING contains any upper-case letters,
1437perform-replace also turns off `case-fold-search' temporarily
1438and inserts the replacement text without altering case in it.
1439
1440+++
1441** The function buffer-size now accepts an optional argument
1442to specify which buffer to return the size of.
1443
1444+++
1445** The calendar motion commands now run the normal hook
1446calendar-move-hook after moving point.
1447
1448+++
1449** The new variable small-temporary-file-directory specifies a
1450directory to use for creating temporary files that are likely to be
1451small. (Certain Emacs features use this directory.) If
1452small-temporary-file-directory is nil, they use
1453temporary-file-directory instead.
1454
1455+++
1456** The variable `inhibit-modification-hooks', if non-nil, inhibits all
1457the hooks that track changes in the buffer. This affects
1458`before-change-functions' and `after-change-functions', as well as
1459hooks attached to text properties and overlay properties.
1460
1461+++
1462** assoc-delete-all is a new function that deletes all the
1463elements of an alist which have a particular value as the car.
1464
1465+++
1466** make-temp-file provides a more reliable way to create a temporary file.
1467
1468make-temp-file is used like make-temp-name, except that it actually
1469creates the file before it returns. This prevents a timing error,
1470ensuring that no other job can use the same name for a temporary file.
1471
1472+++
1473** New exclusive-open feature in `write-region'
1474
1475The optional seventh arg is now called MUSTBENEW. If non-nil, it insists
1476on a check for an existing file with the same name. If MUSTBENEW
1477is `excl', that means to get an error if the file already exists;
1478never overwrite. If MUSTBENEW is neither nil nor `excl', that means
1479ask for confirmation before overwriting, but do go ahead and
1480overwrite the file if the user gives confirmation.
1481
1482If the MUSTBENEW argument in `write-region' is `excl',
1483that means to use a special feature in the `open' system call
1484to get an error if the file exists at that time.
1485The error reported is `file-already-exists'.
1486
1487+++
1488** Function `format' now handles text properties.
1489
1490Text properties of the format string are applied to the result string.
1491If the result string is longer than the format string, text properties
1492ending at the end of the format string are extended to the end of the
1493result string.
1494
1495Text properties from string arguments are applied to the result
1496string where arguments appear in the result string.
1497
1498Example:
1499
1500 (let ((s1 "hello, %s")
1501 (s2 "world"))
1502 (put-text-property 0 (length s1) 'face 'bold s1)
1503 (put-text-property 0 (length s2) 'face 'italic s2)
b246b1f6 1504 (format s1 s2))
a933dad1
DL
1505
1506results in a bold-face string with an italic `world' at the end.
1507
1508+++
1509** Messages can now be displayed with text properties.
1510
1511Text properties are handled as described above for function `format'.
1512The following example displays a bold-face message with an italic
1513argument in it.
1514
1515 (let ((msg "hello, %s!")
1516 (arg "world"))
1517 (put-text-property 0 (length msg) 'face 'bold msg)
1518 (put-text-property 0 (length arg) 'face 'italic arg)
1519 (message msg arg))
1520
1521+++
1522** Sound support
1523
1524Emacs supports playing sound files on GNU/Linux and the free BSDs
1525(Voxware driver and native BSD driver, aka as Luigi's driver).
1526
1527Currently supported file formats are RIFF-WAVE (*.wav) and Sun Audio
1528(*.au). You must configure Emacs with the option `--with-sound=yes'
1529to enable sound support.
1530
1531Sound files can be played by calling (play-sound SOUND). SOUND is a
1532list of the form `(sound PROPERTY...)'. The function is only defined
1533when sound support is present for the system on which Emacs runs. The
1534functions runs `play-sound-functions' with one argument which is the
1535sound to play, before playing the sound.
1536
1537The following sound properties are supported:
1538
1539- `:file FILE'
1540
1541FILE is a file name. If FILE isn't an absolute name, it will be
1542searched relative to `data-directory'.
1543
6fb40beb
GM
1544- `:data DATA'
1545
1546DATA is a string containing sound data. Either :file or :data
1547may be present, but not both.
1548
a933dad1
DL
1549- `:volume VOLUME'
1550
1551VOLUME must be an integer in the range 0..100 or a float in the range
15520..1. This property is optional.
1553
1554Other properties are ignored.
1555
1556** `multimedia' is a new Finder keyword and Custom group.
356673d4
DL
1557
1558** keywordp is a new predicate to test efficiently for an object being
1559a keyword symbol.
fc91dc2d
GM
1560
1561** Changes to garbage collection
1562
1563*** The function garbage-collect now additionally returns the number
1564of live and free strings.
1565
1566*** There is a new variable `strings-consed' holding the number of
1567strings that have been consed so far.
1568
a933dad1
DL
1569\f
1570* New Lisp-level Display features in Emacs 21.1
1571
1572Note that +++ before an item means the Lisp manual has been updated.
1573--- means that I have decided it does not need to be in the Lisp manual.
1574When you add a new item, please add it without either +++ or ---
1575so I will know I still need to look at it -- rms.
1576
1577** New face implementation.
1578
1579Emacs faces have been reimplemented from scratch. They don't use XLFD
1580font names anymore and face merging now works as expected.
1581
1582+++
1583*** New faces.
1584
1585Each face can specify the following display attributes:
1586
1587 1. Font family or fontset alias name.
79214ddf 1588
a933dad1
DL
1589 2. Relative proportionate width, aka character set width or set
1590 width (swidth), e.g. `semi-compressed'.
79214ddf 1591
a933dad1 1592 3. Font height in 1/10pt
79214ddf 1593
a933dad1 1594 4. Font weight, e.g. `bold'.
79214ddf 1595
a933dad1 1596 5. Font slant, e.g. `italic'.
79214ddf 1597
a933dad1 1598 6. Foreground color.
79214ddf 1599
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1600 7. Background color.
1601
1602 8. Whether or not characters should be underlined, and in what color.
1603
1604 9. Whether or not characters should be displayed in inverse video.
1605
1606 10. A background stipple, a bitmap.
1607
1608 11. Whether or not characters should be overlined, and in what color.
1609
1610 12. Whether or not characters should be strike-through, and in what
1611 color.
1612
1613 13. Whether or not a box should be drawn around characters, its
1614 color, the width of the box lines, and 3D appearance.
1615
1616Faces are frame-local by nature because Emacs allows to define the
1617same named face (face names are symbols) differently for different
1618frames. Each frame has an alist of face definitions for all named
1619faces. The value of a named face in such an alist is a Lisp vector
1620with the symbol `face' in slot 0, and a slot for each each of the face
1621attributes mentioned above.
1622
1623There is also a global face alist `face-new-frame-defaults'. Face
1624definitions from this list are used to initialize faces of newly
1625created frames.
79214ddf 1626
a933dad1
DL
1627A face doesn't have to specify all attributes. Those not specified
1628have a nil value. Faces specifying all attributes are called
1629`fully-specified'.
1630
1631+++
1632*** Face merging.
1633
1634The display style of a given character in the text is determined by
1635combining several faces. This process is called `face merging'. Any
1636aspect of the display style that isn't specified by overlays or text
1637properties is taken from the `default' face. Since it is made sure
1638that the default face is always fully-specified, face merging always
1639results in a fully-specified face.
1640
1641+++
1642*** Face realization.
1643
1644After all face attributes for a character have been determined by
1645merging faces of that character, that face is `realized'. The
1646realization process maps face attributes to what is physically
1647available on the system where Emacs runs. The result is a `realized
1648face' in form of an internal structure which is stored in the face
1649cache of the frame on which it was realized.
1650
1651Face realization is done in the context of the charset of the
1652character to display because different fonts and encodings are used
1653for different charsets. In other words, for characters of different
1654charsets, different realized faces are needed to display them.
1655
1656Except for composite characters, faces are always realized for a
1657specific character set and contain a specific font, even if the face
1658being realized specifies a fontset. The reason is that the result of
1659the new font selection stage is better than what can be done with
1660statically defined font name patterns in fontsets.
1661
1662In unibyte text, Emacs' charsets aren't applicable; function
1663`char-charset' reports ASCII for all characters, including those >
16640x7f. The X registry and encoding of fonts to use is determined from
1665the variable `face-default-registry' in this case. The variable is
1666initialized at Emacs startup time from the font the user specified for
1667Emacs.
1668
1669Currently all unibyte text, i.e. all buffers with
1670`enable-multibyte-characters' nil are displayed with fonts of the same
1671registry and encoding `face-default-registry'. This is consistent
1672with the fact that languages can also be set globally, only.
1673
1674++++
1675**** Clearing face caches.
1676
1677The Lisp function `clear-face-cache' can be called to clear face caches
1678on all frames. If called with a non-nil argument, it will also unload
1679unused fonts.
1680
1681+++
1682*** Font selection.
79214ddf 1683
a933dad1
DL
1684Font selection tries to find the best available matching font for a
1685given (charset, face) combination. This is done slightly differently
1686for faces specifying a fontset, or a font family name.
1687
1688If the face specifies a fontset name, that fontset determines a
1689pattern for fonts of the given charset. If the face specifies a font
1690family, a font pattern is constructed. Charset symbols have a
1691property `x-charset-registry' for that purpose that maps a charset to
1692an XLFD registry and encoding in the font pattern constructed.
1693
1694Available fonts on the system on which Emacs runs are then matched
1695against the font pattern. The result of font selection is the best
1696match for the given face attributes in this font list.
1697
1698Font selection can be influenced by the user.
1699
1700The user can specify the relative importance he gives the face
1701attributes width, height, weight, and slant by setting
1702face-font-selection-order (faces.el) to a list of face attribute
1703names. The default is (:width :height :weight :slant), and means
1704that font selection first tries to find a good match for the font
1705width specified by a face, then---within fonts with that width---tries
1706to find a best match for the specified font height, etc.
1707
1708Setting `face-alternative-font-family-alist' allows the user to
1709specify alternative font families to try if a family specified by a
1710face doesn't exist.
1711
1712+++
1713**** Scalable fonts
1714
1715Emacs can make use of scalable fonts but doesn't do so by default,
1716since the use of too many or too big scalable fonts may crash XFree86
1717servers.
1718
1719To enable scalable font use, set the variable
b246b1f6 1720`scalable-fonts-allowed'. A value of nil, the default, means never use
a933dad1
DL
1721scalable fonts. A value of t means any scalable font may be used.
1722Otherwise, the value must be a list of regular expressions. A
1723scalable font may then be used if it matches a regular expression from
1724that list. Example:
1725
1726 (setq scalable-fonts-allowed '("muleindian-2$"))
1727
1728allows the use of scalable fonts with registry `muleindian-2'.
1729
1730+++
1731*** Functions and variables related to font selection.
1732
1733- Function: x-family-fonts &optional FAMILY FRAME
1734
1735Return a list of available fonts of family FAMILY on FRAME. If FAMILY
1736is omitted or nil, list all families. Otherwise, FAMILY must be a
1737string, possibly containing wildcards `?' and `*'.
1738
1739If FRAME is omitted or nil, use the selected frame. Each element of
1740the result is a vector [FAMILY WIDTH POINT-SIZE WEIGHT SLANT FIXED-P
1741FULL REGISTRY-AND-ENCODING]. FAMILY is the font family name.
1742POINT-SIZE is the size of the font in 1/10 pt. WIDTH, WEIGHT, and
1743SLANT are symbols describing the width, weight and slant of the font.
1744These symbols are the same as for face attributes. FIXED-P is non-nil
1745if the font is fixed-pitch. FULL is the full name of the font, and
1746REGISTRY-AND-ENCODING is a string giving the registry and encoding of
1747the font. The result list is sorted according to the current setting
1748of the face font sort order.
1749
79214ddf 1750- Function: x-font-family-list
a933dad1
DL
1751
1752Return a list of available font families on FRAME. If FRAME is
1753omitted or nil, use the selected frame. Value is a list of conses
1754(FAMILY . FIXED-P) where FAMILY is a font family, and FIXED-P is
1755non-nil if fonts of that family are fixed-pitch.
1756
1757- Variable: font-list-limit
1758
1759Limit for font matching. If an integer > 0, font matching functions
1760won't load more than that number of fonts when searching for a
1761matching font. The default is currently 100.
1762
1763+++
1764*** Setting face attributes.
1765
1766For the most part, the new face implementation is interface-compatible
1767with the old one. Old face attribute related functions are now
1768implemented in terms of the new functions `set-face-attribute' and
1769`face-attribute'.
1770
1771Face attributes are identified by their names which are keyword
1772symbols. All attributes can be set to `unspecified'.
1773
1774The following attributes are recognized:
1775
1776`:family'
1777
1778VALUE must be a string specifying the font family, e.g. ``courier'',
1779or a fontset alias name. If a font family is specified, wild-cards `*'
1780and `?' are allowed.
1781
1782`:width'
1783
1784VALUE specifies the relative proportionate width of the font to use.
1785It must be one of the symbols `ultra-condensed', `extra-condensed',
1786`condensed', `semi-condensed', `normal', `semi-expanded', `expanded',
1787`extra-expanded', or `ultra-expanded'.
1788
1789`:height'
1790
1791VALUE must be an integer specifying the height of the font to use in
17921/10 pt.
1793
1794`:weight'
1795
1796VALUE specifies the weight of the font to use. It must be one of the
1797symbols `ultra-bold', `extra-bold', `bold', `semi-bold', `normal',
1798`semi-light', `light', `extra-light', `ultra-light'.
1799
1800`:slant'
1801
1802VALUE specifies the slant of the font to use. It must be one of the
1803symbols `italic', `oblique', `normal', `reverse-italic', or
1804`reverse-oblique'.
1805
1806`:foreground', `:background'
1807
1808VALUE must be a color name, a string.
1809
1810`:underline'
1811
1812VALUE specifies whether characters in FACE should be underlined. If
1813VALUE is t, underline with foreground color of the face. If VALUE is
1814a string, underline with that color. If VALUE is nil, explicitly
1815don't underline.
1816
1817`:overline'
1818
1819VALUE specifies whether characters in FACE should be overlined. If
1820VALUE is t, overline with foreground color of the face. If VALUE is a
1821string, overline with that color. If VALUE is nil, explicitly don't
1822overline.
1823
1824`:strike-through'
1825
1826VALUE specifies whether characters in FACE should be drawn with a line
1827striking through them. If VALUE is t, use the foreground color of the
1828face. If VALUE is a string, strike-through with that color. If VALUE
1829is nil, explicitly don't strike through.
1830
1831`:box'
1832
1833VALUE specifies whether characters in FACE should have a box drawn
1834around them. If VALUE is nil, explicitly don't draw boxes. If
1835VALUE is t, draw a box with lines of width 1 in the foreground color
1836of the face. If VALUE is a string, the string must be a color name,
1837and the box is drawn in that color with a line width of 1. Otherwise,
1838VALUE must be a property list of the form `(:line-width WIDTH
1839:color COLOR :style STYLE)'. If a keyword/value pair is missing from
1840the property list, a default value will be used for the value, as
1841specified below. WIDTH specifies the width of the lines to draw; it
1842defaults to 1. COLOR is the name of the color to draw in, default is
1843the foreground color of the face for simple boxes, and the background
1844color of the face for 3D boxes. STYLE specifies whether a 3D box
1845should be draw. If STYLE is `released-button', draw a box looking
1846like a released 3D button. If STYLE is `pressed-button' draw a box
1847that appears like a pressed button. If STYLE is nil, the default if
1848the property list doesn't contain a style specification, draw a 2D
1849box.
1850
1851`:inverse-video'
1852
1853VALUE specifies whether characters in FACE should be displayed in
1854inverse video. VALUE must be one of t or nil.
1855
1856`:stipple'
1857
1858If VALUE is a string, it must be the name of a file of pixmap data.
1859The directories listed in the `x-bitmap-file-path' variable are
1860searched. Alternatively, VALUE may be a list of the form (WIDTH
1861HEIGHT DATA) where WIDTH and HEIGHT are the size in pixels, and DATA
1862is a string containing the raw bits of the bitmap. VALUE nil means
1863explicitly don't use a stipple pattern.
1864
1865For convenience, attributes `:family', `:width', `:height', `:weight',
1866and `:slant' may also be set in one step from an X font name:
1867
1868`:font'
1869
1870Set font-related face attributes from VALUE. VALUE must be a valid
1871XLFD font name. If it is a font name pattern, the first matching font
1872is used--this is for compatibility with the behavior of previous
1873versions of Emacs.
1874
1875For compatibility with Emacs 20, keywords `:bold' and `:italic' can
1876be used to specify that a bold or italic font should be used. VALUE
1877must be t or nil in that case. A value of `unspecified' is not allowed."
1878
1879Please see also the documentation of `set-face-attribute' and
1880`defface'.
1881
1882*** Face attributes and X resources
1883
1884The following X resource names can be used to set face attributes
1885from X resources:
1886
1887 Face attribute X resource class
1888-----------------------------------------------------------------------
1889 :family attributeFamily . Face.AttributeFamily
1890 :width attributeWidth Face.AttributeWidth
1891 :height attributeHeight Face.AttributeHeight
1892 :weight attributeWeight Face.AttributeWeight
1893 :slant attributeSlant Face.AttributeSlant
1894 foreground attributeForeground Face.AttributeForeground
1895 :background attributeBackground . Face.AttributeBackground
1896 :overline attributeOverline Face.AttributeOverline
1897 :strike-through attributeStrikeThrough Face.AttributeStrikeThrough
1898 :box attributeBox Face.AttributeBox
1899 :underline attributeUnderline Face.AttributeUnderline
1900 :inverse-video attributeInverse Face.AttributeInverse
1901 :stipple attributeStipple Face.AttributeStipple
79214ddf 1902 or attributeBackgroundPixmap
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1903 Face.AttributeBackgroundPixmap
1904 :font attributeFont Face.AttributeFont
1905 :bold attributeBold Face.AttributeBold
1906 :italic attributeItalic . Face.AttributeItalic
1907 :font attributeFont Face.AttributeFont
1908
1909+++
1910*** Text property `face'.
1911
1912The value of the `face' text property can now be a single face
1913specification or a list of such specifications. Each face
1914specification can be
1915
19161. A symbol or string naming a Lisp face.
1917
19182. A property list of the form (KEYWORD VALUE ...) where each
1919 KEYWORD is a face attribute name, and VALUE is an appropriate value
1920 for that attribute. Please see the doc string of `set-face-attribute'
1921 for face attribute names.
1922
19233. Conses of the form (FOREGROUND-COLOR . COLOR) or
1924 (BACKGROUND-COLOR . COLOR) where COLOR is a color name. This is
1925 for compatibility with previous Emacs versions.
1926
1927+++
1928** Support functions for colors on text-only terminals.
1929
acf3ecb7
EZ
1930The function `tty-color-define' can be used to define colors for use
1931on TTY and MSDOS frames. It maps a color name to a color number on
1932the terminal. Emacs defines a couple of common color mappings by
a933dad1 1933default. You can get defined colors with a call to
acf3ecb7 1934`defined-colors'. The function `tty-color-clear' can be
a933dad1
DL
1935used to clear the mapping table.
1936
acf3ecb7
EZ
1937** Unified support for colors independent of frame type.
1938
1939The new functions `defined-colors', `color-defined-p', `color-values',
1940and `display-color-p' work for any type of frame. On frames whose
1941type is neither x nor w32, these functions transparently map X-style
1942color specifications to the closest colors supported by the frame
1943display. Lisp programs should use these new functions instead of the
1944old `x-defined-colors', `x-color-defined-p', `x-color-values', and
1945`x-display-color-p'. (The old function names are still available for
1946compatibility; they are now aliases of the new names.) Lisp programs
1947should no more look at the value of the variable window-system to
1948modify their color-related behavior.
1949
1950The primitives `color-gray-p' and `color-supported-p' also work for
1951any frame type.
1952
8a5719f0
EZ
1953** Platform-independent functions to describe display capabilities.
1954
1955The new functions `display-mouse-p', `display-popup-menus-p',
1956`display-graphic-p', `display-selections-p', `display-screens',
1957`display-pixel-width', `display-pixel-height', `display-mm-width',
1958`display-mm-height', `display-backing-store', `display-save-under',
1959`display-planes', `display-color-cells', `display-visual-class', and
1960`display-grayscale-p' describe the basic capabilities of a particular
1961display. Lisp programs should call these functions instead of testing
1962the value of the variables `window-system' or `system-type', or calling
1963platform-specific functions such as `x-display-pixel-width'.
1964
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1965+++
1966** The minibuffer prompt is now actually inserted in the minibuffer.
a933dad1 1967
463cac2d 1968This makes it possible to scroll through the prompt, if you want to.
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DL
1969
1970The function minubuffer-prompt-end returns the current position of the
1971end of the minibuffer prompt, if the minibuffer is current.
1972Otherwise, it returns zero.
1973
463cac2d
GM
1974** New `field' abstraction in buffers.
1975
1976There is now code to support an abstraction called `fields' in emacs
1977buffers. A field is a contiguous region of text with the same `field'
1978text-property.
1979
9a9dfda8 1980Many emacs functions, such as forward-word, forward-sentence,
463cac2d 1981forward-paragraph, beginning-of-line, etc., stop moving when they come
9a9dfda8 1982to the boundary between fields; beginning-of-line and end-of-line will
463cac2d 1983not let the point move past the field boundary, but other movement
fc7ac24f
GM
1984commands continue into the next field if repeated. Stopping at field
1985boundaries can be suppressed programmatically by binding
1986`inhibit-field-text-motion' to a non-nil value around calls to these
1987functions.
463cac2d
GM
1988
1989Now that the minibuffer prompt is inserted into the minibuffer, it is in
9a9dfda8 1990a separate field from the user-input part of the buffer, so that common
463cac2d 1991editing commands treat the user's text separately from the prompt.
a933dad1 1992
9a9dfda8
GM
1993The following functions are defined for operating on fields:
1994
1995- Function: constrain-to-field NEW-POS OLD-POS &optional ESCAPE-FROM-EDGE ONLY-IN-LINE
1996
1997Return the position closest to NEW-POS that is in the same field as OLD-POS.
1998A field is a region of text with the same `field' property.
1999If NEW-POS is nil, then the current point is used instead, and set to the
2000constrained position if that is is different.
2001
2002If OLD-POS is at the boundary of two fields, then the allowable
2003positions for NEW-POS depends on the value of the optional argument
2004ESCAPE-FROM-EDGE: If ESCAPE-FROM-EDGE is nil, then NEW-POS is
2005constrained to the field that has the same `field' text-property
2006as any new characters inserted at OLD-POS, whereas if ESCAPE-FROM-EDGE
2007is non-nil, NEW-POS is constrained to the union of the two adjacent
2008fields.
2009
2010If the optional argument ONLY-IN-LINE is non-nil and constraining
2011NEW-POS would move it to a different line, NEW-POS is returned
2012unconstrained. This useful for commands that move by line, like
2013C-n or C-a, which should generally respect field boundaries
2014only in the case where they can still move to the right line.
2015
2016- Function: erase-field &optional POS
2017
2018Erases the field surrounding POS.
2019A field is a region of text with the same `field' property.
2020If POS is nil, the position of the current buffer's point is used.
2021
2022- Function: field-beginning &optional POS ESCAPE-FROM-EDGE
2023
2024Return the beginning of the field surrounding POS.
2025A field is a region of text with the same `field' property.
2026If POS is nil, the position of the current buffer's point is used.
2027If ESCAPE-FROM-EDGE is non-nil and POS is already at beginning of an
2028field, then the beginning of the *previous* field is returned.
2029
2030- Function: field-end &optional POS ESCAPE-FROM-EDGE
2031
2032Return the end of the field surrounding POS.
2033A field is a region of text with the same `field' property.
2034If POS is nil, the position of the current buffer's point is used.
2035If ESCAPE-FROM-EDGE is non-nil and POS is already at end of a field,
2036then the end of the *following* field is returned.
2037
2038- Function: field-string &optional POS
2039
2040Return the contents of the field surrounding POS as a string.
2041A field is a region of text with the same `field' property.
2042If POS is nil, the position of the current buffer's point is used.
2043
2044- Function: field-string-no-properties &optional POS
2045
2046Return the contents of the field around POS, without text-properties.
2047A field is a region of text with the same `field' property.
2048If POS is nil, the position of the current buffer's point is used.
2049
a933dad1
DL
2050+++
2051** Image support.
2052
2053Emacs can now display images. Images are inserted into text by giving
2054strings or buffer text a `display' text property containing one of
2055(AREA IMAGE) or IMAGE. The display of the `display' property value
2056replaces the display of the characters having that property.
2057
2058If the property value has the form (AREA IMAGE), AREA must be one of
2059`(margin left-margin)', `(margin right-margin)' or `(margin nil)'. If
2060AREA is `(margin nil)', IMAGE will be displayed in the text area of a
2061window, otherwise it will be displayed in the left or right marginal
2062area.
2063
2064IMAGE is an image specification.
2065
2066*** Image specifications
2067
2068Image specifications are lists of the form `(image PROPS)' where PROPS
2069is a property list whose keys are keyword symbols. Each
2070specifications must contain a property `:type TYPE' with TYPE being a
35a5514b
GM
2071symbol specifying the image type, e.g. `xbm'. Properties not
2072described below are ignored.
a933dad1
DL
2073
2074The following is a list of properties all image types share.
2075
2076`:ascent ASCENT'
2077
2078ASCENT must be a number in the range 0..100, and specifies the percentage
2079of the image's height to use for its ascent. Default is 50.
2080
2081`:margin MARGIN'
2082
79214ddf 2083MARGIN must be a number >= 0 specifying how many pixels to put as
a933dad1
DL
2084margin around the image. Default is 0.
2085
2086`:relief RELIEF'
2087
2088RELIEF is analogous to the `:relief' attribute of faces. Puts a relief
2089around an image.
2090
2091`:algorithm ALGO'
2092
2093Apply an image algorithm to the image before displaying it. ALGO must
2094be a symbol specifying the algorithm. Currently only `laplace' is
2095supported which applies a Laplace edge detection algorithm to an image
2096which is intended to display images "disabled."
2097
2098`:heuristic-mask BG'
2099
2100If BG is not nil, build a clipping mask for the image, so that the
2101background of a frame is visible behind the image. If BG is t,
2102determine the background color of the image by looking at the 4
2103corners of the image, assuming the most frequently occuring color from
2104the corners is the background color of the image. Otherwise, BG must
2105be a list `(RED GREEN BLUE)' specifying the color to assume for the
2106background of the image.
2107
2108`:file FILE'
2109
2110Load image from FILE. If FILE is not absolute after expanding it,
2111search for the image in `data-directory'. Some image types support
2112building images from data. When this is done, no `:file' property
2113may be present in the image specification.
2114
518df5c4
GM
2115`:data DATA'
2116
2117Get image data from DATA. (As of this writing, this is not yet
2118supported for image type `postscript'). Either :file or :data may be
2119present in an image specification, but not both. All image types
2120support strings as DATA, some types allow additional types of DATA.
2121
a933dad1
DL
2122*** Supported image types
2123
b246b1f6 2124**** XBM, image type `xbm'.
a933dad1
DL
2125
2126XBM images don't require an external library. Additional image
2127properties supported are
2128
2129`:foreground FG'
2130
2131FG must be a string specifying the image foreground color. Default
2132is the frame's foreground.
2133
2134`:background FG'
2135
2136BG must be a string specifying the image foreground color. Default is
2137the frame's background color.
2138
2139XBM images can be constructed from data instead of file. In this
2140case, the image specification must contain the following properties
2141instead of a `:file' property.
2142
2143`:width WIDTH'
2144
2145WIDTH specifies the width of the image in pixels.
2146
2147`:height HEIGHT'
2148
2149HEIGHT specifies the height of the image in pixels.
2150
2151`:data DATA'
2152
2153DATA must be either
2154
2155 1. a string large enough to hold the bitmap data, i.e. it must
2156 have a size >= (WIDTH + 7) / 8 * HEIGHT
2157
2158 2. a bool-vector of size >= WIDTH * HEIGHT
2159
2160 3. a vector of strings or bool-vectors, one for each line of the
2161 bitmap.
2162
2163**** XPM, image type `xpm'
2164
2165XPM images require the external library `libXpm', package
2166`xpm-3.4k.tar.gz', version 3.4k or later. Make sure the library is
2167found when Emacs is configured by supplying appropriate paths via
2168`--x-includes' and `--x-libraries'.
2169
2170Additional image properties supported are:
2171
2172`:color-symbols SYMBOLS'
2173
2174SYMBOLS must be a list of pairs (NAME . COLOR), with NAME being the
2175name of color as it appears in an XPM file, and COLOR being an X color
2176name.
2177
2178XPM images can be built from memory instead of files. In that case,
2179add a `:data' property instead of a `:file' property.
2180
a933dad1
DL
2181The XPM library uses libz in its implementation so that it is able
2182to display compressed images.
2183
2184**** PBM, image type `pbm'
2185
2186PBM images don't require an external library. Color, gray-scale and
2187mono images are supported. There are no additional image properties
2188defined.
2189
2190**** JPEG, image type `jpeg'
2191
2192Support for JPEG images requires the external library `libjpeg',
3bd37feb
GM
2193package `jpegsrc.v6a.tar.gz', or later. Additional image properties
2194are:
2195
a933dad1
DL
2196**** TIFF, image type `tiff'
2197
2198Support for TIFF images requires the external library `libtiff',
2199package `tiff-v3.4-tar.gz', or later. There are no additional image
2200properties defined.
2201
2202**** GIF, image type `gif'
2203
2204Support for GIF images requires the external library `libungif', package
2205`libungif-4.1.0', or later.
2206
2207Additional image properties supported are:
2208
2209`:index INDEX'
2210
2211INDEX must be an integer >= 0. Load image number INDEX from a
2212multi-image GIF file. An error is signalled if INDEX is too large.
2213
2214This could be used to implement limited support for animated GIFs.
2215For example, the following function displays a multi-image GIF file
2216at point-min in the current buffer, switching between sub-images
2217every 0.1 seconds.
2218
2219(defun show-anim (file max)
2220 "Display multi-image GIF file FILE which contains MAX subimages."
2221 (display-anim (current-buffer) file 0 max t))
2222
2223(defun display-anim (buffer file idx max first-time)
2224 (when (= idx max)
2225 (setq idx 0))
518df5c4 2226 (let ((img (create-image file nil nil :index idx)))
a933dad1
DL
2227 (save-excursion
2228 (set-buffer buffer)
2229 (goto-char (point-min))
2230 (unless first-time (delete-char 1))
2231 (insert-image img "x"))
2232 (run-with-timer 0.1 nil 'display-anim buffer file (1+ idx) max nil)))
2233
2234**** PNG, image type `png'
2235
2236Support for PNG images requires the external library `libpng',
2237package `libpng-1.0.2.tar.gz', or later. There are no additional image
2238properties defined.
2239
2240**** Ghostscript, image type `postscript'.
2241
2242Additional image properties supported are:
2243
2244`:pt-width WIDTH'
2245
2246WIDTH is width of the image in pt (1/72 inch). WIDTH must be an
b246b1f6 2247integer. This is a required property.
a933dad1
DL
2248
2249`:pt-height HEIGHT'
2250
2251HEIGHT specifies the height of the image in pt (1/72 inch). HEIGHT
b246b1f6 2252must be a integer. This is an required property.
a933dad1
DL
2253
2254`:bounding-box BOX'
2255
2256BOX must be a list or vector of 4 integers giving the bounding box of
2257the PS image, analogous to the `BoundingBox' comment found in PS
2258files. This is an required property.
2259
2260Part of the Ghostscript interface is implemented in Lisp. See
2261lisp/gs.el.
2262
2263*** Lisp interface.
2264
79214ddf
FP
2265The variable `image-types' contains a list of those image types
2266which are supported in the current configuration.
a933dad1
DL
2267
2268Images are stored in an image cache and removed from the cache when
2269they haven't been displayed for `image-cache-eviction-delay seconds.
2270The function `clear-image-cache' can be used to clear the image cache
2271manually.
2272
2273*** Simplified image API, image.el
2274
2275The new Lisp package image.el contains functions that simplify image
2276creation and putting images into text. The function `create-image'
2277can be used to create images. The macro `defimage' can be used to
2278define an image based on available image types. The functions
2279`put-image' and `insert-image' can be used to insert an image into a
2280buffer.
2281
2282+++
2283** Display margins.
2284
2285Windows can now have margins which are used for special text
2286and images.
2287
2288To give a window margins, either set the buffer-local variables
2289`left-margin-width' and `right-margin-width', or call
2290`set-window-margins'. The function `window-margins' can be used to
2291obtain the current settings. To make `left-margin-width' and
2292`right-margin-width' take effect, you must set them before displaying
2293the buffer in a window, or use `set-window-buffer' to force an update
2294of the display margins.
2295
2296You can put text in margins by giving it a `display' text property
2297containing a pair of the form `(LOCATION . VALUE)', where LOCATION is
2298one of `left-margin' or `right-margin' or nil. VALUE can be either a
2299string, an image specification or a stretch specification (see later
2300in this file).
2301
2302+++
2303** Help display
2304
2305Emacs displays short help messages in the echo area, when the mouse
2306moves over a tool-bar item or a piece of text that has a text property
2307`help-echo'. This feature also applies to strings in the mode line
2308that have a `help-echo' property.
2309
2310The value of the `help-echo' property must be a string. For tool-bar
2311items, their key definition is used to determine the help to display.
2312If their definition contains a property `:help FORM', FORM is
2313evaluated to determine the help string. Otherwise, the caption of the
2314tool-bar item is used.
2315
2316The hook `show-help-function' can be set to a function that displays
2317help differently. For example, enabling a tooltip window causes the
2318help display to appear there instead of in the echo area.
2319
2320+++
2321** Vertical fractional scrolling.
2322
2323The display of text in windows can be scrolled smoothly in pixels.
2324This is useful, for example, for making parts of large images visible.
2325
2326The function `window-vscroll' returns the current value of vertical
2327scrolling, a non-negative fraction of the canonical character height.
2328The function `set-window-vscroll' can be used to set the vertical
2329scrolling value. Here is an example of how these function might be
2330used.
2331
79214ddf
FP
2332 (global-set-key [A-down]
2333 #'(lambda ()
a933dad1 2334 (interactive)
79214ddf 2335 (set-window-vscroll (selected-window)
a933dad1 2336 (+ 0.5 (window-vscroll)))))
79214ddf 2337 (global-set-key [A-up]
a933dad1
DL
2338 #'(lambda ()
2339 (interactive)
79214ddf 2340 (set-window-vscroll (selected-window)
a933dad1
DL
2341 (- (window-vscroll) 0.5)))))
2342
2343+++
2344** New hook `fontification-functions'.
2345
2346Functions from `fontification-functions' are called from redisplay
2347when it encounters a region of text that is not yet fontified. This
2348variable automatically becomes buffer-local when set. Each function
2349is called with one argument, POS.
2350
2351At least one of the hook functions should fontify one or more
2352characters starting at POS in the current buffer. It should mark them
2353as fontified by giving them a non-nil value of the `fontified' text
2354property. It may be reasonable for these functions to check for the
2355`fontified' property and not put it back on, but they do not have to.
2356
2357+++
2358** Tool bar support.
2359
2360Emacs supports a tool bar at the top of a frame under X. The frame
2361parameter `tool-bar-lines' (X resource "toolBar", class "ToolBar")
2362controls how may lines to reserve for the tool bar. A zero value
2363suppresses the tool bar. If the value is non-zero and
2364`auto-resize-tool-bars' is non-nil the tool bar's size will be changed
2365automatically so that all tool bar items are visible.
2366
2367*** Tool bar item definitions
2368
2369Tool bar items are defined using `define-key' with a prefix-key
2370`tool-bar'. For example `(define-key global-map [tool-bar item1] ITEM)'
2371where ITEM is a list `(menu-item CAPTION BINDING PROPS...)'.
79214ddf 2372
a933dad1
DL
2373CAPTION is the caption of the item, If it's not a string, it is
2374evaluated to get a string. The caption is currently not displayed in
2375the tool bar, but it is displayed if the item doesn't have a `:help'
2376property (see below).
79214ddf 2377
a933dad1
DL
2378BINDING is the tool bar item's binding. Tool bar items with keymaps as
2379binding are currently ignored.
2380
2381The following properties are recognized:
2382
2383`:enable FORM'.
79214ddf 2384
a933dad1
DL
2385FORM is evaluated and specifies whether the tool bar item is enabled
2386or disabled.
79214ddf 2387
a933dad1 2388`:visible FORM'
79214ddf 2389
a933dad1 2390FORM is evaluated and specifies whether the tool bar item is displayed.
79214ddf 2391
a933dad1
DL
2392`:filter FUNCTION'
2393
2394FUNCTION is called with one parameter, the same list BINDING in which
2395FUNCTION is specified as the filter. The value FUNCTION returns is
2396used instead of BINDING to display this item.
79214ddf 2397
a933dad1
DL
2398`:button (TYPE SELECTED)'
2399
2400TYPE must be one of `:radio' or `:toggle'. SELECTED is evaluated
2401and specifies whether the button is selected (pressed) or not.
79214ddf 2402
a933dad1
DL
2403`:image IMAGES'
2404
2405IMAGES is either a single image specification or a vector of four
2406image specifications. If it is a vector, this table lists the
2407meaning of each of the four elements:
2408
2409 Index Use when item is
2410 ----------------------------------------
2411 0 enabled and selected
2412 1 enabled and deselected
2413 2 disabled and selected
2414 3 disabled and deselected
79214ddf 2415
a933dad1 2416`:help HELP-STRING'.
79214ddf 2417
a933dad1
DL
2418Gives a help string to display for the tool bar item. This help
2419is displayed when the mouse is moved over the item.
2420
2421*** Tool-bar-related variables.
2422
2423If `auto-resize-tool-bar' is non-nil, the tool bar will automatically
2424resize to show all defined tool bar items. It will never grow larger
2425than 1/4 of the frame's size.
2426
79214ddf 2427If `auto-raise-tool-bar-buttons' is non-nil, tool bar buttons will be
a933dad1
DL
2428raised when the mouse moves over them.
2429
2430You can add extra space between tool bar items by setting
2431`tool-bar-button-margin' to a positive integer specifying a number of
2432pixels. Default is 1.
2433
2434You can change the shadow thickness of tool bar buttons by setting
2435`tool-bar-button-relief' to an integer. Default is 3.
2436
2437*** Tool-bar clicks with modifiers.
2438
2439You can bind commands to clicks with control, shift, meta etc. on
79214ddf 2440a tool bar item. If
a933dad1
DL
2441
2442 (define-key global-map [tool-bar shell]
2443 '(menu-item "Shell" shell
2444 :image (image :type xpm :file "shell.xpm")))
2445
2446is the original tool bar item definition, then
2447
2448 (define-key global-map [tool-bar S-shell] 'some-command)
2449
2450makes a binding to run `some-command' for a shifted click on the same
2451item.
2452
2453** Mode line changes.
2454
2455+++
2456*** Mouse-sensitive mode line.
2457
2458The mode line can be made mouse-sensitive by displaying strings there
2459that have a `local-map' text property. There are three ways to display
2460a string with a `local-map' property in the mode line.
2461
24621. The mode line spec contains a variable whose string value has
2463a `local-map' text property.
2464
24652. The mode line spec contains a format specifier (e.g. `%12b'), and
2466that format specifier has a `local-map' property.
2467
24683. The mode line spec contains a list containing `:eval FORM'. FORM
2469is evaluated. If the result is a string, and that string has a
2470`local-map' property.
2471
2472The same mechanism is used to determine the `face' and `help-echo'
2473properties of strings in the mode line. See `bindings.el' for an
2474example.
2475
54522c9f
GM
2476*** If a mode line element has the form `(:eval FORM)', FORM is
2477evaluated and the result is used as mode line element.
2478
a933dad1
DL
2479+++
2480*** You can suppress mode-line display by setting the buffer-local
2481variable mode-line-format to nil.
2482
2483+++
2484*** A headerline can now be displayed at the top of a window.
2485
2486This mode line's contents are controlled by the new variable
2487`header-line-format' and `default-header-line-format' which are
2488completely analogous to `mode-line-format' and
2489`default-mode-line-format'. A value of nil means don't display a top
2490line.
2491
2492The appearance of top mode lines is controlled by the face
2493`header-line'.
2494
2495The function `coordinates-in-window-p' returns `header-line' for a
2496position in the header-line.
2497
2498+++
2499** Text property `display'
2500
2501The `display' text property is used to insert images into text, and
2502also control other aspects of how text displays. The value of the
2503`display' property should be a display specification, as described
2504below, or a list or vector containing display specifications.
2505
2506*** Variable width and height spaces
2507
2508To display a space of fractional width or height, use a display
2509specification of the form `(LOCATION STRECH)'. If LOCATION is
2510`(margin left-margin)', the space is displayed in the left marginal
2511area, if it is `(margin right-margin)', it is displayed in the right
2512marginal area, and if LOCATION is `(margin nil)' the space is
2513displayed in the text. In the latter case you can also use the
2514simpler form STRETCH as property value.
2515
2516The stretch specification STRETCH itself is a list of the form `(space
2517PROPS)', where PROPS is a property list which can contain the
2518properties described below.
2519
2520The display of the fractional space replaces the display of the
2521characters having the `display' property.
2522
2523- :width WIDTH
2524
2525Specifies that the space width should be WIDTH times the normal
2526character width. WIDTH can be an integer or floating point number.
2527
2528- :relative-width FACTOR
2529
2530Specifies that the width of the stretch should be computed from the
2531first character in a group of consecutive characters that have the
2532same `display' property. The computation is done by multiplying the
2533width of that character by FACTOR.
2534
2535- :align-to HPOS
2536
2537Specifies that the space should be wide enough to reach HPOS. The
2538value HPOS is measured in units of the normal character width.
2539
2540Exactly one of the above properties should be used.
2541
2542- :height HEIGHT
2543
2544Specifies the height of the space, as HEIGHT, measured in terms of the
2545normal line height.
2546
2547- :relative-height FACTOR
2548
2549The height of the space is computed as the product of the height
2550of the text having the `display' property and FACTOR.
2551
2552- :ascent ASCENT
2553
2554Specifies that ASCENT percent of the height of the stretch should be
2555used for the ascent of the stretch, i.e. for the part above the
2556baseline. The value of ASCENT must be a non-negative number less or
2557equal to 100.
2558
2559You should not use both `:height' and `:relative-height' together.
2560
2561*** Images
2562
2563A display specification for an image has the form `(LOCATION
2564. IMAGE)', where IMAGE is an image specification. The image replaces,
2565in the display, the characters having this display specification in
2566their `display' text property. If LOCATION is `(margin left-margin)',
2567the image will be displayed in the left marginal area, if it is
2568`(margin right-margin)' it will be displayed in the right marginal
2569area, and if LOCATION is `(margin nil)' the image will be displayed in
2570the text. In the latter case you can also use the simpler form IMAGE
2571as display specification.
2572
2573*** Other display properties
2574
2575- :space-width FACTOR
2576
2577Specifies that space characters in the text having that property
2578should be displayed FACTOR times as wide as normal; FACTOR must be an
2579integer or float.
2580
2581- :height HEIGHT
2582
2583Display text having this property in a font that is smaller or larger.
2584
2585If HEIGHT is a list of the form `(+ N)', where N is an integer, that
2586means to use a font that is N steps larger. If HEIGHT is a list of
2587the form `(- N)', that means to use a font that is N steps smaller. A
2588``step'' is defined by the set of available fonts; each size for which
2589a font is available counts as a step.
2590
2591If HEIGHT is a number, that means to use a font that is HEIGHT times
2592as tall as the frame's default font.
2593
2594If HEIGHT is a symbol, it is called as a function with the current
2595height as argument. The function should return the new height to use.
2596
2597Otherwise, HEIGHT is evaluated to get the new height, with the symbol
2598`height' bound to the current specified font height.
2599
2600- :raise FACTOR
2601
2602FACTOR must be a number, specifying a multiple of the current
2603font's height. If it is positive, that means to display the characters
2604raised. If it is negative, that means to display them lower down. The
2605amount of raising or lowering is computed without taking account of the
2606`:height' subproperty.
2607
2608*** Conditional display properties
2609
2610All display specifications can be conditionalized. If a specification
2611has the form `(:when CONDITION . SPEC)', the specification SPEC
2612applies only when CONDITION yields a non-nil value when evaluated.
2613During evaluattion, point is temporarily set to the end position of
2614the text having the `display' property.
2615
2616The normal specification consisting of SPEC only is equivalent to
2617`(:when t SPEC)'.
2618
2619+++
2620** New menu separator types.
2621
2622Emacs now supports more than one menu separator type. Menu items with
2623item names consisting of dashes only (including zero dashes) are
2624treated like before. In addition, the following item names are used
2625to specify other menu separator types.
2626
2627- `--no-line' or `--space', or `--:space', or `--:noLine'
2628
2629No separator lines are drawn, but a small space is inserted where the
2630separator occurs.
2631
2632- `--single-line' or `--:singleLine'
2633
2634A single line in the menu's foreground color.
2635
2636- `--double-line' or `--:doubleLine'
2637
2638A double line in the menu's foreground color.
2639
2640- `--single-dashed-line' or `--:singleDashedLine'
2641
2642A single dashed line in the menu's foreground color.
2643
2644- `--double-dashed-line' or `--:doubleDashedLine'
2645
2646A double dashed line in the menu's foreground color.
2647
2648- `--shadow-etched-in' or `--:shadowEtchedIn'
2649
2650A single line with 3D sunken appearance. This is the the form
2651displayed for item names consisting of dashes only.
2652
2653- `--shadow-etched-out' or `--:shadowEtchedOut'
2654
2655A single line with 3D raised appearance.
2656
2657- `--shadow-etched-in-dash' or `--:shadowEtchedInDash'
2658
2659A single dashed line with 3D sunken appearance.
2660
2661- `--shadow-etched-out-dash' or `--:shadowEtchedOutDash'
2662
2663A single dashed line with 3D raise appearance.
2664
2665- `--shadow-double-etched-in' or `--:shadowDoubleEtchedIn'
2666
2667Two lines with 3D sunken appearance.
2668
2669- `--shadow-double-etched-out' or `--:shadowDoubleEtchedOut'
2670
2671Two lines with 3D raised appearance.
2672
2673- `--shadow-double-etched-in-dash' or `--:shadowDoubleEtchedInDash'
2674
2675Two dashed lines with 3D sunken appearance.
2676
2677- `--shadow-double-etched-out-dash' or `--:shadowDoubleEtchedOutDash'
2678
2679Two dashed lines with 3D raised appearance.
2680
2681Under LessTif/Motif, the last four separator types are displayed like
2682the corresponding single-line separators.
2683
2684+++
2685** New frame parameters for scroll bar colors.
2686
2687The new frame parameters `scroll-bar-foreground' and
2688`scroll-bar-background' can be used to change scroll bar colors.
2689Their value must be either a color name, a string, or nil to specify
2690that scroll bars should use a default color. For toolkit scroll bars,
2691default colors are toolkit specific. For non-toolkit scroll bars, the
2692default background is the background color of the frame, and the
2693default foreground is black.
2694
2695The X resource name of these parameters are `scrollBarForeground'
2696(class ScrollBarForeground) and `scrollBarBackground' (class
2697`ScrollBarBackground').
2698
2699Setting these parameters overrides toolkit specific X resource
2700settings for scroll bar colors.
2701
2702+++
2703** You can set `redisplay-dont-pause' to a non-nil value to prevent
2704display updates from being interrupted when input is pending.
2705
2706---
2707** Changing a window's width may now change its window start if it
2708starts on a continuation line. The new window start is computed based
2709on the window's new width, starting from the start of the continued
2710line as the start of the screen line with the minimum distance from
2711the original window start.
2712
2713---
2714** The variable `hscroll-step' and the functions
2715`hscroll-point-visible' and `hscroll-window-column' have been removed
2716now that proper horizontal scrolling is implemented.
2717
2718+++
2719** Windows can now be made fixed-width and/or fixed-height.
2720
2721A window is fixed-size if its buffer has a buffer-local variable
2722`window-size-fixed' whose value is not nil. A value of `height' makes
2723windows fixed-height, a value of `width' makes them fixed-width, any
2724other non-nil value makes them both fixed-width and fixed-height.
2725
2726The following code makes all windows displaying the current buffer
2727fixed-width and fixed-height.
2728
2729 (set (make-local-variable 'window-size-fixed) t)
2730
2731A call to enlarge-window on a window gives an error if that window is
2732fixed-width and it is tried to change the window's width, or if the
2733window is fixed-height, and it is tried to change its height. To
2734change the size of a fixed-size window, bind `window-size-fixed'
2735temporarily to nil, for example
2736
2737 (let ((window-size-fixed nil))
2738 (enlarge-window 10))
2739
79214ddf 2740Likewise, an attempt to split a fixed-height window vertically,
a933dad1 2741or a fixed-width window horizontally results in a error.
e411ce4b
EZ
2742
2743** The cursor-type frame parameter is now supported on MS-DOS
2744terminals. When Emacs starts, it by default changes the cursor shape
2745to a solid box, as it does on Unix. The `cursor-type' frame parameter
2746overrides this as it does on Unix, except that the bar cursor is
2747horizontal rather than vertical (since the MS-DOS display doesn't
2748support a vertical-bar cursor).
e33b0397
DL
2749^L
2750* Emacs 20.5 is a bug-fix release with no user-visible changes.
2751
2752** Not new, but not mentioned before:
2753M-w when Transient Mark mode is enabled disables the mark.
a933dad1
DL
2754\f
2755* Changes in Emacs 20.4
2756
2757** Init file may be called .emacs.el.
2758
2759You can now call the Emacs init file `.emacs.el'.
2760Formerly the name had to be `.emacs'. If you use the name
2761`.emacs.el', you can byte-compile the file in the usual way.
2762
2763If both `.emacs' and `.emacs.el' exist, the latter file
2764is the one that is used.
2765
2766** shell-command, and shell-command-on-region, now return
2767the exit code of the command (unless it is asynchronous).
2768Also, you can specify a place to put the error output,
2769separate from the command's regular output.
2770Interactively, the variable shell-command-default-error-buffer
2771says where to put error output; set it to a buffer name.
2772In calls from Lisp, an optional argument ERROR-BUFFER specifies
2773the buffer name.
2774
2775When you specify a non-nil error buffer (or buffer name), any error
2776output is inserted before point in that buffer, with \f\n to separate
2777it from the previous batch of error output. The error buffer is not
2778cleared, so error output from successive commands accumulates there.
2779
2780** Setting the default value of enable-multibyte-characters to nil in
2781the .emacs file, either explicitly using setq-default, or via Custom,
2782is now essentially equivalent to using --unibyte: all buffers
2783created during startup will be made unibyte after loading .emacs.
2784
2785** C-x C-f now handles the wildcards * and ? in file names. For
2786example, typing C-x C-f c*.c RET visits all the files whose names
2787match c*.c. To visit a file whose name contains * or ?, add the
2788quoting sequence /: to the beginning of the file name.
2789
2790** The M-x commands keep-lines, flush-lines and count-matches
2791now have the same feature as occur and query-replace:
2792if the pattern contains any upper case letters, then
2793they never ignore case.
2794
2795** The end-of-line format conversion feature previously mentioned
2796under `* Emacs 20.1 changes for MS-DOS and MS-Windows' actually
2797applies to all operating systems. Emacs recognizes from the contents
2798of a file what convention it uses to separate lines--newline, CRLF, or
2799just CR--and automatically converts the contents to the normal Emacs
2800convention (using newline to separate lines) for editing. This is a
2801part of the general feature of coding system conversion.
2802
2803If you subsequently save the buffer, Emacs converts the text back to
2804the same format that was used in the file before.
2805
2806You can turn off end-of-line conversion by setting the variable
2807`inhibit-eol-conversion' to non-nil, e.g. with Custom in the MULE group.
2808
2809** The character set property `prefered-coding-system' has been
2810renamed to `preferred-coding-system', for the sake of correct spelling.
2811This is a fairly internal feature, so few programs should be affected.
2812
2813** Mode-line display of end-of-line format is changed.
2814The indication of the end-of-line format of the file visited by a
2815buffer is now more explicit when that format is not the usual one for
2816your operating system. For example, the DOS-style end-of-line format
2817is displayed as "(DOS)" on Unix and GNU/Linux systems. The usual
2818end-of-line format is still displayed as a single character (colon for
2819Unix, backslash for DOS and Windows, and forward slash for the Mac).
2820
2821The values of the variables eol-mnemonic-unix, eol-mnemonic-dos,
2822eol-mnemonic-mac, and eol-mnemonic-undecided, which are strings,
2823control what is displayed in the mode line for each end-of-line
2824format. You can now customize these variables.
2825
2826** In the previous version of Emacs, tar-mode didn't work well if a
2827filename contained non-ASCII characters. Now this is fixed. Such a
2828filename is decoded by file-name-coding-system if the default value of
2829enable-multibyte-characters is non-nil.
2830
2831** The command temp-buffer-resize-mode toggles a minor mode
2832in which temporary buffers (such as help buffers) are given
2833windows just big enough to hold the whole contents.
2834
2835** If you use completion.el, you must now run the function
2836dynamic-completion-mode to enable it. Just loading the file
2837doesn't have any effect.
2838
2839** In Flyspell mode, the default is now to make just one Ispell process,
2840not one per buffer.
2841
2842** If you use iswitchb but do not call (iswitchb-default-keybindings) to
2843use the default keybindings, you will need to add the following line:
2844 (add-hook 'minibuffer-setup-hook 'iswitchb-minibuffer-setup)
2845
2846** Auto-show mode is no longer enabled just by loading auto-show.el.
2847To control it, set `auto-show-mode' via Custom or use the
2848`auto-show-mode' command.
2849
2850** Handling of X fonts' ascent/descent parameters has been changed to
2851avoid redisplay problems. As a consequence, compared with previous
2852versions the line spacing and frame size now differ with some font
2853choices, typically increasing by a pixel per line. This change
2854occurred in version 20.3 but was not documented then.
2855
2856** If you select the bar cursor style, it uses the frame's
2857cursor-color, rather than the cursor foreground pixel.
2858
2859** In multibyte mode, Rmail decodes incoming MIME messages using the
2860character set specified in the message. If you want to disable this
2861feature, set the variable rmail-decode-mime-charset to nil.
2862
2863** Not new, but not mentioned previously in NEWS: when you use #! at
2864the beginning of a file to make it executable and specify an
2865interpreter program, Emacs looks on the second line for the -*- mode
2866and variable specification, as well as on the first line.
2867
2868** Support for IBM codepage encoding of non-ASCII characters.
2869
2870The new command M-x codepage-setup creates a special coding system
2871that can be used to convert text between a specific IBM codepage and
2872one of the character sets built into Emacs which matches that
2873codepage. For example, codepage 850 corresponds to Latin-1 character
2874set, codepage 855 corresponds to Cyrillic-ISO character set, etc.
2875
2876Windows codepages 1250, 1251 and some others, where Windows deviates
2877from the corresponding ISO character set, are also supported.
2878
2879IBM box-drawing characters and other glyphs which don't have
2880equivalents in the corresponding ISO character set, are converted to
2881a character defined by dos-unsupported-char-glyph on MS-DOS, and to
2882`?' on other systems.
2883
2884IBM codepages are widely used on MS-DOS and MS-Windows, so this
2885feature is most useful on those platforms, but it can also be used on
2886Unix.
2887
2888Emacs compiled for MS-DOS automatically loads the support for the
2889current codepage when it starts.
2890
2891** Mail changes
2892
feab4fba
GM
2893*** When mail is sent using compose-mail (C-x m), and if
2894`mail-send-nonascii' is set to the new default value `mime',
2895appropriate MIME headers are added. The headers are added only if
2896non-ASCII characters are present in the body of the mail, and no other
2897MIME headers are already present. For example, the following three
2898headers are added if the coding system used in the *mail* buffer is
2899latin-1:
2900
2901 MIME-version: 1.0
2902 Content-type: text/plain; charset=iso-8859-1
2903 Content-Transfer-Encoding: 8bit
2904
a933dad1
DL
2905*** The new variable default-sendmail-coding-system specifies the
2906default way to encode outgoing mail. This has higher priority than
2907default-buffer-file-coding-system but has lower priority than
2908sendmail-coding-system and the local value of
2909buffer-file-coding-system.
2910
2911You should not set this variable manually. Instead, set
2912sendmail-coding-system to specify a fixed encoding for all outgoing
2913mail.
2914
2915*** When you try to send a message that contains non-ASCII characters,
2916if the coding system specified by those variables doesn't handle them,
2917Emacs will ask you to select a suitable coding system while showing a
2918list of possible coding systems.
2919
2920** CC Mode changes
2921
2922*** c-default-style can now take an association list that maps major
2923modes to style names. When this variable is an alist, Java mode no
2924longer hardcodes a setting to "java" style. See the variable's
2925docstring for details.
2926
2927*** It's now possible to put a list as the offset on a syntactic
2928symbol. The list is evaluated recursively until a non-nil offset is
2929found. This is useful to combine several lineup functions to act in a
2930prioritized order on a single line. However, none of the supplied
2931lineup functions use this feature currently.
2932
2933*** New syntactic symbol catch-clause, which is used on the "catch" and
2934"finally" lines in try-catch constructs in C++ and Java.
2935
2936*** New cleanup brace-catch-brace on c-cleanup-list, which does for
2937"catch" lines what brace-elseif-brace does for "else if" lines.
2938
2939*** The braces of Java anonymous inner classes are treated separately
2940from the braces of other classes in auto-newline mode. Two new
2941symbols inexpr-class-open and inexpr-class-close may be used on
2942c-hanging-braces-alist to control the automatic newlines used for
2943anonymous classes.
2944
2945*** Support for the Pike language added, along with new Pike specific
2946syntactic symbols: inlambda, lambda-intro-cont
2947
2948*** Support for Java anonymous classes via new syntactic symbol
2949inexpr-class. New syntactic symbol inexpr-statement for Pike
2950support and gcc-style statements inside expressions. New lineup
2951function c-lineup-inexpr-block.
2952
2953*** New syntactic symbol brace-entry-open which is used in brace lists
2954(i.e. static initializers) when a list entry starts with an open
2955brace. These used to be recognized as brace-list-entry's.
2956c-electric-brace also recognizes brace-entry-open braces
2957(brace-list-entry's can no longer be electrified).
2958
2959*** New command c-indent-line-or-region, not bound by default.
2960
2961*** `#' is only electric when typed in the indentation of a line.
2962
2963*** Parentheses are now electric (via the new command c-electric-paren)
2964for auto-reindenting lines when parens are typed.
2965
2966*** In "gnu" style, inline-open offset is now set to zero.
2967
2968*** Uniform handling of the inclass syntactic symbol. The indentation
2969associated with it is now always relative to the class opening brace.
2970This means that the indentation behavior has changed in some
2971circumstances, but only if you've put anything besides 0 on the
2972class-open syntactic symbol (none of the default styles do that).
2973
2974** Gnus changes.
2975
2976*** New functionality for using Gnus as an offline newsreader has been
2977added. A plethora of new commands and modes have been added. See the
2978Gnus manual for the full story.
2979
2980*** The nndraft backend has returned, but works differently than
2981before. All Message buffers are now also articles in the nndraft
2982group, which is created automatically.
2983
2984*** `gnus-alter-header-function' can now be used to alter header
2985values.
2986
2987*** `gnus-summary-goto-article' now accept Message-ID's.
2988
2989*** A new Message command for deleting text in the body of a message
2990outside the region: `C-c C-v'.
2991
2992*** You can now post to component group in nnvirtual groups with
2993`C-u C-c C-c'.
2994
2995*** `nntp-rlogin-program' -- new variable to ease customization.
2996
2997*** `C-u C-c C-c' in `gnus-article-edit-mode' will now inhibit
2998re-highlighting of the article buffer.
2999
3000*** New element in `gnus-boring-article-headers' -- `long-to'.
3001
3002*** `M-i' symbolic prefix command. See the section "Symbolic
3003Prefixes" in the Gnus manual for details.
3004
3005*** `L' and `I' in the summary buffer now take the symbolic prefix
3006`a' to add the score rule to the "all.SCORE" file.
3007
3008*** `gnus-simplify-subject-functions' variable to allow greater
3009control over simplification.
3010
3011*** `A T' -- new command for fetching the current thread.
3012
3013*** `/ T' -- new command for including the current thread in the
3014limit.
3015
3016*** `M-RET' is a new Message command for breaking cited text.
3017
3018*** \\1-expressions are now valid in `nnmail-split-methods'.
3019
79214ddf 3020*** The `custom-face-lookup' function has been removed.
a933dad1
DL
3021If you used this function in your initialization files, you must
3022rewrite them to use `face-spec-set' instead.
3023
3024*** Cancelling now uses the current select method. Symbolic prefix
3025`a' forces normal posting method.
3026
3027*** New command to translate M******** sm*rtq**t*s into proper text
3028-- `W d'.
3029
3030*** For easier debugging of nntp, you can set `nntp-record-commands'
3031to a non-nil value.
3032
3033*** nntp now uses ~/.authinfo, a .netrc-like file, for controlling
3034where and how to send AUTHINFO to NNTP servers.
3035
3036*** A command for editing group parameters from the summary buffer
3037has been added.
3038
3039*** A history of where mails have been split is available.
3040
3041*** A new article date command has been added -- `article-date-iso8601'.
3042
3043*** Subjects can be simplified when threading by setting
3044`gnus-score-thread-simplify'.
3045
3046*** A new function for citing in Message has been added --
3047`message-cite-original-without-signature'.
3048
3049*** `article-strip-all-blank-lines' -- new article command.
3050
3051*** A new Message command to kill to the end of the article has
3052been added.
3053
3054*** A minimum adaptive score can be specified by using the
3055`gnus-adaptive-word-minimum' variable.
3056
3057*** The "lapsed date" article header can be kept continually
3058updated by the `gnus-start-date-timer' command.
3059
3060*** Web listserv archives can be read with the nnlistserv backend.
3061
3062*** Old dejanews archives can now be read by nnweb.
3063
3064*** `gnus-posting-styles' has been re-activated.
3065
3066** Changes to TeX and LaTeX mode
3067
3068*** The new variable `tex-start-options-string' can be used to give
3069options for the TeX run. The default value causes TeX to run in
3070nonstopmode. For an interactive TeX run set it to nil or "".
3071
3072*** The command `tex-feed-input' sends input to the Tex Shell. In a
3073TeX buffer it is bound to the keys C-RET, C-c RET, and C-c C-m (some
3074of these keys may not work on all systems). For instance, if you run
3075TeX interactively and if the TeX run stops because of an error, you
3076can continue it without leaving the TeX buffer by typing C-RET.
3077
3078*** The Tex Shell Buffer is now in `compilation-shell-minor-mode'.
3079All error-parsing commands of the Compilation major mode are available
3080but bound to keys that don't collide with the shell. Thus you can use
3081the Tex Shell for command line executions like a usual shell.
3082
3083*** The commands `tex-validate-region' and `tex-validate-buffer' check
3084the matching of braces and $'s. The errors are listed in a *Occur*
3085buffer and you can use C-c C-c or mouse-2 to go to a particular
3086mismatch.
3087
3088** Changes to RefTeX mode
3089
3090*** The table of contents buffer can now also display labels and
3091file boundaries in addition to sections. Use `l', `i', and `c' keys.
3092
3093*** Labels derived from context (the section heading) are now
3094lowercase by default. To make the label legal in LaTeX, latin-1
3095characters will lose their accent. All Mule characters will be
3096removed from the label.
3097
3098*** The automatic display of cross reference information can also use
3099a window instead of the echo area. See variable `reftex-auto-view-crossref'.
3100
3101*** kpsewhich can be used by RefTeX to find TeX and BibTeX files. See the
3102customization group `reftex-finding-files'.
3103
3104*** The option `reftex-bibfile-ignore-list' has been renamed to
3105`reftex-bibfile-ignore-regexps' and indeed can be fed with regular
79214ddf 3106expressions.
a933dad1
DL
3107
3108*** Multiple Selection buffers are now hidden buffers.
3109
3110** New/deleted modes and packages
3111
3112*** The package snmp-mode.el provides major modes for editing SNMP and
3113SNMPv2 MIBs. It has entries on `auto-mode-alist'.
3114
3115*** The package sql.el provides a major mode, M-x sql-mode, for
3116editing SQL files, and M-x sql-interactive-mode for interacting with
3117SQL interpreters. It has an entry on `auto-mode-alist'.
3118
3119*** M-x highlight-changes-mode provides a minor mode displaying buffer
3120changes with a special face.
3121
3122*** ispell4.el has been deleted. It got in the way of ispell.el and
3123this was hard to fix reliably. It has long been obsolete -- use
3124Ispell 3.1 and ispell.el.
3125\f
3126* MS-DOS changes in Emacs 20.4
3127
3128** Emacs compiled for MS-DOS now supports MULE features better.
3129This includes support for display of all ISO 8859-N character sets,
3130conversion to and from IBM codepage encoding of non-ASCII characters,
3131and automatic setup of the MULE environment at startup. For details,
3132check out the section `MS-DOS and MULE' in the manual.
3133
3134The MS-DOS installation procedure automatically configures and builds
3135Emacs with input method support if it finds an unpacked Leim
3136distribution when the config.bat script is run.
3137
3138** Formerly, the value of lpr-command did not affect printing on
3139MS-DOS unless print-region-function was set to nil, but now it
3140controls whether an external program is invoked or output is written
3141directly to a printer port. Similarly, in the previous version of
3142Emacs, the value of ps-lpr-command did not affect PostScript printing
3143on MS-DOS unless ps-printer-name was set to something other than a
3144string (eg. t or `pipe'), but now it controls whether an external
3145program is used. (These changes were made so that configuration of
3146printing variables would be almost identical across all platforms.)
3147
3148** In the previous version of Emacs, PostScript and non-PostScript
3149output was piped to external programs, but because most print programs
3150available for MS-DOS and MS-Windows cannot read data from their standard
3151input, on those systems the data to be output is now written to a
3152temporary file whose name is passed as the last argument to the external
3153program.
3154
3155An exception is made for `print', a standard program on Windows NT,
3156and `nprint', a standard program on Novell Netware. For both of these
3157programs, the command line is constructed in the appropriate syntax
3158automatically, using only the value of printer-name or ps-printer-name
3159as appropriate--the value of the relevant `-switches' variable is
3160ignored, as both programs have no useful switches.
3161
3162** The value of the variable dos-printer (cf. dos-ps-printer), if it has
3163a value, overrides the value of printer-name (cf. ps-printer-name), on
3164MS-DOS and MS-Windows only. This has been true since version 20.3, but
3165was not documented clearly before.
3166
3167** All the Emacs games now work on MS-DOS terminals.
3168This includes Tetris and Snake.
3169\f
3170* Lisp changes in Emacs 20.4
3171
3172** New functions line-beginning-position and line-end-position
3173return the position of the beginning or end of the current line.
3174They both accept an optional argument, which has the same
3175meaning as the argument to beginning-of-line or end-of-line.
3176
3177** find-file and allied functions now have an optional argument
3178WILDCARD. If this is non-nil, they do wildcard processing,
3179and visit all files that match the wildcard pattern.
3180
3181** Changes in the file-attributes function.
3182
3183*** The file size returned by file-attributes may be an integer or a float.
3184It is an integer if the size fits in a Lisp integer, float otherwise.
3185
3186*** The inode number returned by file-attributes may be an integer (if
3187the number fits in a Lisp integer) or a cons cell containing two
3188integers.
3189
3190** The new function directory-files-and-attributes returns a list of
3191files in a directory and their attributes. It accepts the same
3192arguments as directory-files and has similar semantics, except that
3193file names and attributes are returned.
3194
3195** The new function file-attributes-lessp is a helper function for
3196sorting the list generated by directory-files-and-attributes. It
3197accepts two arguments, each a list of a file name and its atttributes.
3198It compares the file names of each according to string-lessp and
3199returns the result.
3200
3201** The new function file-expand-wildcards expands a wildcard-pattern
3202to produce a list of existing files that match the pattern.
3203
3204** New functions for base64 conversion:
3205
3206The function base64-encode-region converts a part of the buffer
3207into the base64 code used in MIME. base64-decode-region
3208performs the opposite conversion. Line-breaking is supported
3209optionally.
3210
3211Functions base64-encode-string and base64-decode-string do a similar
3212job on the text in a string. They return the value as a new string.
3213
3214**
3215The new function process-running-child-p
3216will tell you if a subprocess has given control of its
3217terminal to its own child process.
3218
3219** interrupt-process and such functions have a new feature:
3220when the second argument is `lambda', they send a signal
3221to the running child of the subshell, if any, but if the shell
3222itself owns its terminal, no signal is sent.
3223
3224** There are new widget types `plist' and `alist' which can
3225be used for customizing variables whose values are plists or alists.
3226
3227** easymenu.el Now understands `:key-sequence' and `:style button'.
3228:included is an alias for :visible.
3229
3230easy-menu-add-item now understands the values returned by
3231easy-menu-remove-item and easy-menu-item-present-p. This can be used
3232to move or copy menu entries.
3233
3234** Multibyte editing changes
3235
3236*** The definitions of sref and char-bytes are changed. Now, sref is
3237an alias of aref and char-bytes always returns 1. This change is to
3238make some Emacs Lisp code which works on 20.2 and earlier also
3239work on the latest Emacs. Such code uses a combination of sref and
3240char-bytes in a loop typically as below:
3241 (setq char (sref str idx)
3242 idx (+ idx (char-bytes idx)))
3243The byte-compiler now warns that this is obsolete.
3244
3245If you want to know how many bytes a specific multibyte character
3246(say, CH) occupies in a multibyte buffer, use this code:
3247 (charset-bytes (char-charset ch))
3248
3249*** In multibyte mode, when you narrow a buffer to some region, and the
3250region is preceded or followed by non-ASCII codes, inserting or
3251deleting at the head or the end of the region may signal this error:
3252
3253 Byte combining across boundary of accessible buffer text inhibitted
3254
3255This is to avoid some bytes being combined together into a character
3256across the boundary.
3257
3258*** The functions find-charset-region and find-charset-string include
3259`unknown' in the returned list in the following cases:
3260 o The current buffer or the target string is unibyte and
3261 contains 8-bit characters.
3262 o The current buffer or the target string is multibyte and
3263 contains invalid characters.
3264
3265*** The functions decode-coding-region and encode-coding-region remove
3266text properties of the target region. Ideally, they should correctly
3267preserve text properties, but for the moment, it's hard. Removing
3268text properties is better than preserving them in a less-than-correct
3269way.
3270
3271*** prefer-coding-system sets EOL conversion of default coding systems.
3272If the argument to prefer-coding-system specifies a certain type of
3273end of line conversion, the default coding systems set by
3274prefer-coding-system will specify that conversion type for end of line.
3275
3276*** The new function thai-compose-string can be used to properly
3277compose Thai characters in a string.
3278
3279** The primitive `define-prefix-command' now takes an optional third
3280argument NAME, which should be a string. It supplies the menu name
3281for the created keymap. Keymaps created in order to be displayed as
3282menus should always use the third argument.
3283
3284** The meanings of optional second arguments for read-char,
3285read-event, and read-char-exclusive are flipped. Now the second
3286arguments are INHERIT-INPUT-METHOD. These functions use the current
3287input method (if any) if and only if INHERIT-INPUT-METHOD is non-nil.
3288
3289** The new function clear-this-command-keys empties out the contents
3290of the vector that (this-command-keys) returns. This is useful in
3291programs that read passwords, to prevent the passwords from echoing
3292inadvertently as part of the next command in certain cases.
3293
3294** The new macro `with-temp-message' displays a temporary message in
3295the echo area, while executing some Lisp code. Like `progn', it
3296returns the value of the last form, but it also restores the previous
3297echo area contents.
3298
3299 (with-temp-message MESSAGE &rest BODY)
3300
3301** The function `require' now takes an optional third argument
3302NOERROR. If it is non-nil, then there is no error if the
3303requested feature cannot be loaded.
3304
3305** In the function modify-face, an argument of (nil) for the
3306foreground color, background color or stipple pattern
79214ddf 3307means to clear out that attribute.
a933dad1
DL
3308
3309** The `outer-window-id' frame property of an X frame
3310gives the window number of the outermost X window for the frame.
3311
3312** Temporary buffers made with with-output-to-temp-buffer are now
3313read-only by default, and normally use the major mode Help mode
3314unless you put them in some other non-Fundamental mode before the
3315end of with-output-to-temp-buffer.
3316
3317** The new functions gap-position and gap-size return information on
3318the gap of the current buffer.
3319
3320** The new functions position-bytes and byte-to-position provide a way
3321to convert between character positions and byte positions in the
3322current buffer.
3323
3324** vc.el defines two new macros, `edit-vc-file' and `with-vc-file', to
3325facilitate working with version-controlled files from Lisp programs.
3326These macros check out a given file automatically if needed, and check
3327it back in after any modifications have been made.
3328\f
3329* Installation Changes in Emacs 20.3
3330
3331** The default value of load-path now includes most subdirectories of
3332the site-specific directories /usr/local/share/emacs/site-lisp and
3333/usr/local/share/emacs/VERSION/site-lisp, in addition to those
3334directories themselves. Both immediate subdirectories and
3335subdirectories multiple levels down are added to load-path.
3336
3337Not all subdirectories are included, though. Subdirectories whose
3338names do not start with a letter or digit are excluded.
3339Subdirectories named RCS or CVS are excluded. Also, a subdirectory
3340which contains a file named `.nosearch' is excluded. You can use
3341these methods to prevent certain subdirectories from being searched.
3342
3343Emacs finds these subdirectories and adds them to load-path when it
3344starts up. While it would be cleaner to find the subdirectories each
3345time Emacs loads a file, that would be much slower.
3346
3347This feature is an incompatible change. If you have stored some Emacs
3348Lisp files in a subdirectory of the site-lisp directory specifically
3349to prevent them from being used, you will need to rename the
3350subdirectory to start with a non-alphanumeric character, or create a
3351`.nosearch' file in it, in order to continue to achieve the desired
3352results.
3353
3354** Emacs no longer includes an old version of the C preprocessor from
3355GCC. This was formerly used to help compile Emacs with C compilers
3356that had limits on the significant length of an identifier, but in
3357fact we stopped supporting such compilers some time ago.
3358\f
3359* Changes in Emacs 20.3
3360
3361** The new command C-x z (repeat) repeats the previous command
3362including its argument. If you repeat the z afterward,
3363it repeats the command additional times; thus, you can
3364perform many repetitions with one keystroke per repetition.
3365
3366** Emacs now supports "selective undo" which undoes only within a
3367specified region. To do this, set point and mark around the desired
3368region and type C-u C-x u (or C-u C-_). You can then continue undoing
3369further, within the same region, by repeating the ordinary undo
3370command C-x u or C-_. This will keep undoing changes that were made
3371within the region you originally specified, until either all of them
3372are undone, or it encounters a change which crosses the edge of that
3373region.
3374
3375In Transient Mark mode, undoing when a region is active requests
3376selective undo.
3377
3378** If you specify --unibyte when starting Emacs, then all buffers are
3379unibyte, except when a Lisp program specifically creates a multibyte
3380buffer. Setting the environment variable EMACS_UNIBYTE has the same
3381effect. The --no-unibyte option overrides EMACS_UNIBYTE and directs
3382Emacs to run normally in multibyte mode.
3383
3384The option --unibyte does not affect the reading of Emacs Lisp files,
3385though. If you want a Lisp file to be read in unibyte mode, use
3386-*-unibyte: t;-*- on its first line. That will force Emacs to
3387load that file in unibyte mode, regardless of how Emacs was started.
3388
3389** toggle-enable-multibyte-characters no longer has a key binding and
3390no longer appears in the menu bar. We've realized that changing the
3391enable-multibyte-characters variable in an existing buffer is
3392something that most users not do.
3393
3394** You can specify a coding system to use for the next cut or paste
3395operations through the window system with the command C-x RET X.
3396The coding system can make a difference for communication with other
3397applications.
3398
3399C-x RET x specifies a coding system for all subsequent cutting and
3400pasting operations.
3401
3402** You can specify the printer to use for commands that do printing by
3403setting the variable `printer-name'. Just what a printer name looks
3404like depends on your operating system. You can specify a different
3405printer for the Postscript printing commands by setting
3406`ps-printer-name'.
3407
3408** Emacs now supports on-the-fly spell checking by the means of a
3409minor mode. It is called M-x flyspell-mode. You don't have to remember
3410any other special commands to use it, and you will hardly notice it
3411except when you make a spelling error. Flyspell works by highlighting
3412incorrect words as soon as they are completed or as soon as the cursor
3413hits a new word.
3414
3415Flyspell mode works with whichever dictionary you have selected for
3416Ispell in Emacs. In TeX mode, it understands TeX syntax so as not
3417to be confused by TeX commands.
3418
3419You can correct a misspelled word by editing it into something
3420correct. You can also correct it, or accept it as correct, by
3421clicking on the word with Mouse-2; that gives you a pop-up menu
3422of various alternative replacements and actions.
3423
3424Flyspell mode also proposes "automatic" corrections. M-TAB replaces
3425the current misspelled word with a possible correction. If several
3426corrections are made possible, M-TAB cycles through them in
3427alphabetical order, or in order of decreasing likelihood if
3428flyspell-sort-corrections is nil.
3429
3430Flyspell mode also flags an error when a word is repeated, if
3431flyspell-mark-duplications-flag is non-nil.
3432
3433** Changes in input method usage.
3434
3435Now you can use arrow keys (right, left, down, up) for selecting among
3436the alternatives just the same way as you do by C-f, C-b, C-n, and C-p
3437respectively.
3438
3439You can use the ENTER key to accept the current conversion.
3440
3441If you type TAB to display a list of alternatives, you can select one
3442of the alternatives with Mouse-2.
3443
3444The meaning of the variable `input-method-verbose-flag' is changed so
3445that you can set it to t, nil, `default', or `complex-only'.
3446
3447 If the value is nil, extra guidance is never given.
3448
3449 If the value is t, extra guidance is always given.
3450
3451 If the value is `complex-only', extra guidance is always given only
3452 when you are using complex input methods such as chinese-py.
3453
3454 If the value is `default' (this is the default), extra guidance is
79214ddf 3455 given in the following case:
a933dad1
DL
3456 o When you are using a complex input method.
3457 o When you are using a simple input method but not in the minibuffer.
3458
3459If you are using Emacs through a very slow line, setting
3460input-method-verbose-flag to nil or to complex-only is a good choice,
3461and if you are using an input method you are not familiar with,
3462setting it to t is helpful.
3463
3464The old command select-input-method is now called set-input-method.
3465
3466In the language environment "Korean", you can use the following
3467keys:
3468 Shift-SPC toggle-korean-input-method
3469 C-F9 quail-hangul-switch-symbol-ksc
3470 F9 quail-hangul-switch-hanja
3471These key bindings are canceled when you switch to another language
3472environment.
3473
3474** The minibuffer history of file names now records the specified file
3475names, not the entire minibuffer input. For example, if the
3476minibuffer starts out with /usr/foo/, you might type in /etc/passwd to
3477get
3478
3479 /usr/foo//etc/passwd
3480
3481which stands for the file /etc/passwd.
3482
3483Formerly, this used to put /usr/foo//etc/passwd in the history list.
3484Now this puts just /etc/passwd in the history list.
3485
3486** If you are root, Emacs sets backup-by-copying-when-mismatch to t
3487at startup, so that saving a file will be sure to preserve
3488its owner and group.
3489
3490** find-func.el can now also find the place of definition of Emacs
3491Lisp variables in user-loaded libraries.
3492
3493** C-x r t (string-rectangle) now deletes the existing rectangle
3494contents before inserting the specified string on each line.
3495
3496** There is a new command delete-whitespace-rectangle
3497which deletes whitespace starting from a particular column
3498in all the lines on a rectangle. The column is specified
3499by the left edge of the rectangle.
3500
3501** You can now store a number into a register with C-u NUMBER C-x r n REG,
3502increment it by INC with C-u INC C-x r + REG (to increment by one, omit
3503C-u INC), and insert it in the buffer with C-x r g REG. This is useful
3504for writing keyboard macros.
3505
3506** The new command M-x speedbar displays a frame in which directories,
3507files, and tags can be displayed, manipulated, and jumped to. The
3508frame defaults to 20 characters in width, and is the same height as
3509the frame that it was started from. Some major modes define
3510additional commands for the speedbar, including Rmail, GUD/GDB, and
3511info.
3512
3513** query-replace-regexp is now bound to C-M-%.
3514
3515** In Transient Mark mode, when the region is active, M-x
3516query-replace and the other replace commands now operate on the region
3517contents only.
3518
3519** M-x write-region, when used interactively, now asks for
3520confirmation before overwriting an existing file. When you call
3521the function from a Lisp program, a new optional argument CONFIRM
3522says whether to ask for confirmation in this case.
3523
3524** If you use find-file-literally and the file is already visited
3525non-literally, the command asks you whether to revisit the file
3526literally. If you say no, it signals an error.
3527
3528** Major modes defined with the "derived mode" feature
3529now use the proper name for the mode hook: WHATEVER-mode-hook.
3530Formerly they used the name WHATEVER-mode-hooks, but that is
3531inconsistent with Emacs conventions.
3532
3533** shell-command-on-region (and shell-command) reports success or
3534failure if the command produces no output.
3535
3536** Set focus-follows-mouse to nil if your window system or window
3537manager does not transfer focus to another window when you just move
3538the mouse.
3539
3540** mouse-menu-buffer-maxlen has been renamed to
3541mouse-buffer-menu-maxlen to be consistent with the other related
3542function and variable names.
3543
3544** The new variable auto-coding-alist specifies coding systems for
3545reading specific files. This has higher priority than
3546file-coding-system-alist.
3547
3548** If you set the variable unibyte-display-via-language-environment to
3549t, then Emacs displays non-ASCII characters are displayed by
3550converting them to the equivalent multibyte characters according to
3551the current language environment. As a result, they are displayed
3552according to the current fontset.
3553
3554** C-q's handling of codes in the range 0200 through 0377 is changed.
3555
3556The codes in the range 0200 through 0237 are inserted as one byte of
3557that code regardless of the values of nonascii-translation-table and
3558nonascii-insert-offset.
3559
3560For the codes in the range 0240 through 0377, if
3561enable-multibyte-characters is non-nil and nonascii-translation-table
3562nor nonascii-insert-offset can't convert them to valid multibyte
3563characters, they are converted to Latin-1 characters.
3564
3565** If you try to find a file that is not read-accessible, you now get
3566an error, rather than an empty buffer and a warning.
3567
3568** In the minibuffer history commands M-r and M-s, an upper case
3569letter in the regular expression forces case-sensitive search.
3570
3571** In the *Help* buffer, cross-references to commands and variables
3572are inferred and hyperlinked. Use C-h m in Help mode for the relevant
3573command keys.
3574
3575** M-x apropos-command, with a prefix argument, no longer looks for
3576user option variables--instead it looks for noninteractive functions.
3577
3578Meanwhile, the command apropos-variable normally searches for
3579user option variables; with a prefix argument, it looks at
3580all variables that have documentation.
3581
3582** When you type a long line in the minibuffer, and the minibuffer
3583shows just one line, automatically scrolling works in a special way
3584that shows you overlap with the previous line of text. The variable
3585minibuffer-scroll-overlap controls how many characters of overlap
3586it should show; the default is 20.
3587
3588Meanwhile, Resize Minibuffer mode is still available; in that mode,
3589the minibuffer grows taller (up to a point) as needed to show the whole
3590of your input.
3591
3592** The new command M-x customize-changed-options lets you customize
3593all the options whose meanings or default values have changed in
3594recent Emacs versions. You specify a previous Emacs version number as
3595argument, and the command creates a customization buffer showing all
3596the customizable options which were changed since that version.
3597Newly added options are included as well.
3598
3599If you don't specify a particular version number argument,
3600then the customization buffer shows all the customizable options
3601for which Emacs versions of changes are recorded.
3602
3603This function is also bound to the Changed Options entry in the
3604Customize menu.
3605
3606** When you run M-x grep with a prefix argument, it figures out
3607the tag around point and puts that into the default grep command.
3608
3609** The new command M-* (pop-tag-mark) pops back through a history of
3610buffer positions from which M-. or other tag-finding commands were
3611invoked.
3612
3613** The new variable comment-padding specifies the number of spaces
3614that `comment-region' will insert before the actual text of the comment.
3615The default is 1.
3616
3617** In Fortran mode the characters `.', `_' and `$' now have symbol
3618syntax, not word syntax. Fortran mode now supports `imenu' and has
3619new commands fortran-join-line (M-^) and fortran-narrow-to-subprogram
3620(C-x n d). M-q can be used to fill a statement or comment block
3621sensibly.
3622
3623** GUD now supports jdb, the Java debugger, and pdb, the Python debugger.
3624
3625** If you set the variable add-log-keep-changes-together to a non-nil
3626value, the command `C-x 4 a' will automatically notice when you make
3627two entries in one day for one file, and combine them.
3628
3629** You can use the command M-x diary-mail-entries to mail yourself a
3630reminder about upcoming diary entries. See the documentation string
3631for a sample shell script for calling this function automatically
3632every night.
3633
3634** All you need to do, to enable use of the Desktop package, is to set
3635the variable desktop-enable to t with Custom.
3636
3637** There is no need to do anything special, now, to enable Gnus to
3638read and post multi-lingual articles.
3639
3640** Outline mode has now support for showing hidden outlines when
3641doing an isearch. In order for this to happen search-invisible should
3642be set to open (the default). If an isearch match is inside a hidden
3643outline the outline is made visible. If you continue pressing C-s and
3644the match moves outside the formerly invisible outline, the outline is
79214ddf 3645made invisible again.
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3646
3647** Mail reading and sending changes
3648
3649*** The Rmail e command now switches to displaying the whole header of
3650the message before it lets you edit the message. This is so that any
3651changes you make in the header will not be lost if you subsequently
3652toggle.
3653
3654*** The w command in Rmail, which writes the message body into a file,
3655now works in the summary buffer as well. (The command to delete the
3656summary buffer is now Q.) The default file name for the w command, if
3657the message has no subject, is stored in the variable
3658rmail-default-body-file.
3659
3660*** Most of the commands and modes that operate on mail and netnews no
3661longer depend on the value of mail-header-separator. Instead, they
3662handle whatever separator the buffer happens to use.
3663
3664*** If you set mail-signature to a value which is not t, nil, or a string,
3665it should be an expression. When you send a message, this expression
3666is evaluated to insert the signature.
3667
3668*** The new Lisp library feedmail.el (version 8) enhances processing of
3669outbound email messages. It works in coordination with other email
3670handling packages (e.g., rmail, VM, gnus) and is responsible for
3671putting final touches on messages and actually submitting them for
3672transmission. Users of the emacs program "fakemail" might be
3673especially interested in trying feedmail.
3674
3675feedmail is not enabled by default. See comments at the top of
3676feedmail.el for set-up instructions. Among the bigger features
3677provided by feedmail are:
3678
3679**** you can park outgoing messages into a disk-based queue and
3680stimulate sending some or all of them later (handy for laptop users);
3681there is also a queue for draft messages
3682
3683**** you can get one last look at the prepped outbound message and
3684be prompted for confirmation
3685
3686**** does smart filling of address headers
3687
3688**** can generate a MESSAGE-ID: line and a DATE: line; the date can be
3689the time the message was written or the time it is being sent; this
3690can make FCC copies more closely resemble copies that recipients get
3691
3692**** you can specify an arbitrary function for actually transmitting
3693the message; included in feedmail are interfaces for /bin/[r]mail,
3694/usr/lib/sendmail, and elisp smtpmail; it's easy to write a new
3695function for something else (10-20 lines of elisp)
3696
3697** Dired changes
3698
3699*** The Dired function dired-do-toggle, which toggles marked and unmarked
3700files, is now bound to "t" instead of "T".
3701
3702*** dired-at-point has been added to ffap.el. It allows one to easily
3703run Dired on the directory name at point.
3704
3705*** Dired has a new command: %g. It searches the contents of
3706files in the directory and marks each file that contains a match
3707for a specified regexp.
3708
3709** VC Changes
3710
3711*** New option vc-ignore-vc-files lets you turn off version control
3712conveniently.
3713
3714*** VC Dired has been completely rewritten. It is now much
3715faster, especially for CVS, and works very similar to ordinary
3716Dired.
3717
3718VC Dired is invoked by typing C-x v d and entering the name of the
3719directory to display. By default, VC Dired gives you a recursive
3720listing of all files at or below the given directory which are
3721currently locked (for CVS, all files not up-to-date are shown).
3722
3723You can change the listing format by setting vc-dired-recurse to nil,
3724then it shows only the given directory, and you may also set
3725vc-dired-terse-display to nil, then it shows all files under version
3726control plus the names of any subdirectories, so that you can type `i'
3727on such lines to insert them manually, as in ordinary Dired.
3728
3729All Dired commands operate normally in VC Dired, except for `v', which
3730is redefined as the version control prefix. That means you may type
3731`v l', `v =' etc. to invoke `vc-print-log', `vc-diff' and the like on
3732the file named in the current Dired buffer line. `v v' invokes
3733`vc-next-action' on this file, or on all files currently marked.
3734
3735The new command `v t' (vc-dired-toggle-terse-mode) allows you to
3736toggle between terse display (only locked files) and full display (all
79214ddf 3737VC files plus subdirectories). There is also a special command,
a933dad1
DL
3738`* l', to mark all files currently locked.
3739
3740Giving a prefix argument to C-x v d now does the same thing as in
3741ordinary Dired: it allows you to supply additional options for the ls
3742command in the minibuffer, to fine-tune VC Dired's output.
3743
3744*** Under CVS, if you merge changes from the repository into a working
3745file, and CVS detects conflicts, VC now offers to start an ediff
3746session to resolve them.
3747
3748Alternatively, you can use the new command `vc-resolve-conflicts' to
3749resolve conflicts in a file at any time. It works in any buffer that
3750contains conflict markers as generated by rcsmerge (which is what CVS
3751uses as well).
3752
3753*** You can now transfer changes between branches, using the new
3754command vc-merge (C-x v m). It is implemented for RCS and CVS. When
3755you invoke it in a buffer under version-control, you can specify
3756either an entire branch or a pair of versions, and the changes on that
3757branch or between the two versions are merged into the working file.
3758If this results in any conflicts, they may be resolved interactively,
3759using ediff.
3760
3761** Changes in Font Lock
3762
3763*** The face and variable previously known as font-lock-reference-face
3764are now called font-lock-constant-face to better reflect their typical
3765use for highlighting constants and labels. (Its face properties are
3766unchanged.) The variable font-lock-reference-face remains for now for
3767compatibility reasons, but its value is font-lock-constant-face.
3768
3769** Frame name display changes
3770
3771*** The command set-frame-name lets you set the name of the current
3772frame. You can use the new command select-frame-by-name to select and
3773raise a frame; this is mostly useful on character-only terminals, or
3774when many frames are invisible or iconified.
3775
3776*** On character-only terminal (not a window system), changing the
3777frame name is now reflected on the mode line and in the Buffers/Frames
3778menu.
3779
3780** Comint (subshell) changes
3781
3782*** In Comint modes, the commands to kill, stop or interrupt a
3783subjob now also kill pending input. This is for compatibility
3784with ordinary shells, where the signal characters do this.
3785
3786*** There are new commands in Comint mode.
3787
3788C-c C-x fetches the "next" line from the input history;
3789that is, the line after the last line you got.
3790You can use this command to fetch successive lines, one by one.
3791
3792C-c SPC accumulates lines of input. More precisely, it arranges to
3793send the current line together with the following line, when you send
3794the following line.
3795
3796C-c C-a if repeated twice consecutively now moves to the process mark,
3797which separates the pending input from the subprocess output and the
3798previously sent input.
3799
3800C-c M-r now runs comint-previous-matching-input-from-input;
3801it searches for a previous command, using the current pending input
3802as the search string.
3803
3804*** New option compilation-scroll-output can be set to scroll
3805automatically in compilation-mode windows.
3806
3807** C mode changes
3808
3809*** Multiline macros are now handled, both as they affect indentation,
3810and as recognized syntax. New syntactic symbol cpp-macro-cont is
3811assigned to second and subsequent lines of a multiline macro
79214ddf 3812definition.
a933dad1
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3813
3814*** A new style "user" which captures all non-hook-ified
3815(i.e. top-level) .emacs file variable settings and customizations.
3816Style "cc-mode" is an alias for "user" and is deprecated. "gnu"
3817style is still the default however.
3818
3819*** "java" style now conforms to Sun's JDK coding style.
3820
3821*** There are new commands c-beginning-of-defun, c-end-of-defun which
3822are alternatives which you could bind to C-M-a and C-M-e if you prefer
3823them. They do not have key bindings by default.
3824
3825*** New and improved implementations of M-a (c-beginning-of-statement)
3826and M-e (c-end-of-statement).
3827
3828*** C++ namespace blocks are supported, with new syntactic symbols
3829namespace-open, namespace-close, and innamespace.
3830
3831*** File local variable settings of c-file-style and c-file-offsets
3832makes the style variables local to that buffer only.
3833
3834*** New indentation functions c-lineup-close-paren,
3835c-indent-one-line-block, c-lineup-dont-change.
3836
3837*** Improvements (hopefully!) to the way CC Mode is loaded. You
3838should now be able to do a (require 'cc-mode) to get the entire
3839package loaded properly for customization in your .emacs file. A new
3840variable c-initialize-on-load controls this and is t by default.
3841
3842** Changes to hippie-expand.
3843
79214ddf 3844*** New customization variable `hippie-expand-dabbrev-skip-space'. If
a933dad1
DL
3845non-nil, trailing spaces may be included in the abbreviation to search for,
3846which then gives the same behavior as the original `dabbrev-expand'.
3847
3848*** New customization variable `hippie-expand-dabbrev-as-symbol'. If
3849non-nil, characters of syntax '_' is considered part of the word when
3850expanding dynamically.
3851
3852*** New customization variable `hippie-expand-no-restriction'. If
3853non-nil, narrowed buffers are widened before they are searched.
3854
3855*** New customization variable `hippie-expand-only-buffers'. If
3856non-empty, buffers searched are restricted to the types specified in
3857this list. Useful for example when constructing new special-purpose
3858expansion functions with `make-hippie-expand-function'.
3859
3860*** Text properties of the expansion are no longer copied.
3861
3862** Changes in BibTeX mode.
3863
3864*** Any titleword matching a regexp in the new variable
3865bibtex-autokey-titleword-ignore (case sensitive) is ignored during
3866automatic key generation. This replaces variable
3867bibtex-autokey-titleword-first-ignore, which only checked for matches
3868against the first word in the title.
3869
3870*** Autokey generation now uses all words from the title, not just
3871capitalized words. To avoid conflicts with existing customizations,
3872bibtex-autokey-titleword-ignore is set up such that words starting with
79214ddf 3873lowerkey characters will still be ignored. Thus, if you want to use
a933dad1 3874lowercase words from the title, you will have to overwrite the
79214ddf 3875bibtex-autokey-titleword-ignore standard setting.
a933dad1
DL
3876
3877*** Case conversion of names and title words for automatic key
3878generation is more flexible. Variable bibtex-autokey-preserve-case is
3879replaced by bibtex-autokey-titleword-case-convert and
3880bibtex-autokey-name-case-convert.
3881
3882** Changes in vcursor.el.
3883
3884*** Support for character terminals is available: there is a new keymap
3885and the vcursor will appear as an arrow between buffer text. A
3886variable `vcursor-interpret-input' allows input from the vcursor to be
3887entered exactly as if typed. Numerous functions, including
3888`vcursor-compare-windows', have been rewritten to improve consistency
3889in the selection of windows and corresponding keymaps.
3890
3891*** vcursor options can now be altered with M-x customize under the
3892Editing group once the package is loaded.
3893
3894*** Loading vcursor now does not define keys by default, as this is
3895generally a bad side effect. Use M-x customize to set
3896vcursor-key-bindings to t to restore the old behaviour.
3897
3898*** vcursor-auto-disable can be `copy', which turns off copying from the
3899vcursor, but doesn't disable it, after any non-vcursor command.
3900
3901** Ispell changes.
3902
79214ddf
FP
3903*** You can now spell check comments and strings in the current
3904buffer with M-x ispell-comments-and-strings. Comments and strings
a933dad1
DL
3905are identified by syntax tables in effect.
3906
3907*** Generic region skipping implemented.
3908A single buffer can be broken into a number of regions where text will
3909and will not be checked. The definitions of the regions can be user
3910defined. New applications and improvements made available by this
79214ddf 3911include:
a933dad1
DL
3912
3913 o URLs are automatically skipped
3914 o EMail message checking is vastly improved.
3915
3916*** Ispell can highlight the erroneous word even on non-window terminals.
3917
3918** Changes to RefTeX mode
3919
3920RefTeX has been updated in order to make it more usable with very
3921large projects (like a several volume math book). The parser has been
3922re-written from scratch. To get maximum speed from RefTeX, check the
3923section `Optimizations' in the manual.
3924
3925*** New recursive parser.
3926
3927The old version of RefTeX created a single large buffer containing the
3928entire multifile document in order to parse the document. The new
3929recursive parser scans the individual files.
3930
3931*** Parsing only part of a document.
79214ddf 3932
a933dad1
DL
3933Reparsing of changed document parts can now be made faster by enabling
3934partial scans. To use this feature, read the documentation string of
3935the variable `reftex-enable-partial-scans' and set the variable to t.
3936
3937 (setq reftex-enable-partial-scans t)
3938
3939*** Storing parsing information in a file.
3940
3941This can improve startup times considerably. To turn it on, use
3942
3943 (setq reftex-save-parse-info t)
3944
3945*** Using multiple selection buffers
3946
3947If the creation of label selection buffers is too slow (this happens
3948for large documents), you can reuse these buffers by setting
3949
3950 (setq reftex-use-multiple-selection-buffers t)
3951
3952*** References to external documents.
3953
3954The LaTeX package `xr' allows to cross-reference labels in external
3955documents. RefTeX can provide information about the external
3956documents as well. To use this feature, set up the \externaldocument
3957macros required by the `xr' package and rescan the document with
3958RefTeX. The external labels can then be accessed with the `x' key in
3959the selection buffer provided by `reftex-reference' (bound to `C-c )').
3960The `x' key also works in the table of contents buffer.
3961
3962*** Many more labeled LaTeX environments are recognized by default.
3963
3964The builtin command list now covers all the standard LaTeX commands,
3965and all of the major packages included in the LaTeX distribution.
3966
3967Also, RefTeX now understands the \appendix macro and changes
3968the enumeration of sections in the *toc* buffer accordingly.
3969
3970*** Mouse support for selection and *toc* buffers
3971
3972The mouse can now be used to select items in the selection and *toc*
3973buffers. See also the new option `reftex-highlight-selection'.
3974
3975*** New keymaps for selection and table of contents modes.
3976
3977The selection processes for labels and citation keys, and the table of
3978contents buffer now have their own keymaps: `reftex-select-label-map',
3979`reftex-select-bib-map', `reftex-toc-map'. The selection processes
3980have a number of new keys predefined. In particular, TAB lets you
3981enter a label with completion. Check the on-the-fly help (press `?'
3982at the selection prompt) or read the Info documentation to find out
3983more.
3984
3985*** Support for the varioref package
3986
3987The `v' key in the label selection buffer toggles \ref versus \vref.
3988
3989*** New hooks
3990
3991Three new hooks can be used to redefine the way labels, references,
3992and citations are created. These hooks are
3993`reftex-format-label-function', `reftex-format-ref-function',
3994`reftex-format-cite-function'.
3995
3996*** Citations outside LaTeX
3997
3998The command `reftex-citation' may also be used outside LaTeX (e.g. in
3999a mail buffer). See the Info documentation for details.
4000
4001*** Short context is no longer fontified.
4002
4003The short context in the label menu no longer copies the
4004fontification from the text in the buffer. If you prefer it to be
4005fontified, use
4006
4007 (setq reftex-refontify-context t)
4008
4009** file-cache-minibuffer-complete now accepts a prefix argument.
4010With a prefix argument, it does not try to do completion of
4011the file name within its directory; it only checks for other
4012directories that contain the same file name.
4013
4014Thus, given the file name Makefile, and assuming that a file
4015Makefile.in exists in the same directory, ordinary
4016file-cache-minibuffer-complete will try to complete Makefile to
4017Makefile.in and will therefore never look for other directories that
4018have Makefile. A prefix argument tells it not to look for longer
4019names such as Makefile.in, so that instead it will look for other
4020directories--just as if the name were already complete in its present
4021directory.
4022
4023** New modes and packages
4024
4025*** There is a new alternative major mode for Perl, Cperl mode.
4026It has many more features than Perl mode, and some people prefer
4027it, but some do not.
4028
4029*** There is a new major mode, M-x vhdl-mode, for editing files of VHDL
4030code.
4031
4032*** M-x which-function-mode enables a minor mode that displays the
4033current function name continuously in the mode line, as you move
4034around in a buffer.
4035
4036Which Function mode is effective in major modes which support Imenu.
4037
4038*** Gametree is a major mode for editing game analysis trees. The author
4039uses it for keeping notes about his postal Chess games, but it should
4040be helpful for other two-player games as well, as long as they have an
4041established system of notation similar to Chess.
4042
4043*** The new minor mode checkdoc-minor-mode provides Emacs Lisp
4044documentation string checking for style and spelling. The style
4045guidelines are found in the Emacs Lisp programming manual.
4046
4047*** The net-utils package makes some common networking features
4048available in Emacs. Some of these functions are wrappers around
4049system utilities (ping, nslookup, etc); others are implementations of
4050simple protocols (finger, whois) in Emacs Lisp. There are also
4051functions to make simple connections to TCP/IP ports for debugging and
4052the like.
4053
4054*** highlight-changes-mode is a minor mode that uses colors to
4055identify recently changed parts of the buffer text.
4056
4057*** The new package `midnight' lets you specify things to be done
4058within Emacs at midnight--by default, kill buffers that you have not
4059used in a considerable time. To use this feature, customize
4060the user option `midnight-mode' to t.
4061
4062*** The file generic-x.el defines a number of simple major modes.
4063
4064 apache-generic-mode: For Apache and NCSA httpd configuration files
4065 samba-generic-mode: Samba configuration files
4066 fvwm-generic-mode: For fvwm initialization files
4067 x-resource-generic-mode: For X resource files
4068 hosts-generic-mode: For hosts files (.rhosts, /etc/hosts, etc)
4069 mailagent-rules-generic-mode: For mailagent .rules files
4070 javascript-generic-mode: For JavaScript files
4071 vrml-generic-mode: For VRML files
4072 java-manifest-generic-mode: For Java MANIFEST files
4073 java-properties-generic-mode: For Java property files
4074 mailrc-generic-mode: For .mailrc files
4075
4076 Platform-specific modes:
4077
4078 prototype-generic-mode: For Solaris/Sys V prototype files
4079 pkginfo-generic-mode: For Solaris/Sys V pkginfo files
4080 alias-generic-mode: For C shell alias files
4081 inf-generic-mode: For MS-Windows INF files
4082 ini-generic-mode: For MS-Windows INI files
4083 reg-generic-mode: For MS-Windows Registry files
4084 bat-generic-mode: For MS-Windows BAT scripts
4085 rc-generic-mode: For MS-Windows Resource files
4086 rul-generic-mode: For InstallShield scripts
4087\f
4088* Lisp changes in Emacs 20.3 since the Emacs Lisp Manual was published
4089
4090** If you want a Lisp file to be read in unibyte mode,
4091use -*-unibyte: t;-*- on its first line.
4092That will force Emacs to read that file in unibyte mode.
4093Otherwise, the file will be loaded and byte-compiled in multibyte mode.
4094
4095Thus, each lisp file is read in a consistent way regardless of whether
4096you started Emacs with --unibyte, so that a Lisp program gives
4097consistent results regardless of how Emacs was started.
4098
4099** The new function assoc-default is useful for searching an alist,
4100and using a default value if the key is not found there. You can
4101specify a comparison predicate, so this function is useful for
4102searching comparing a string against an alist of regular expressions.
4103
4104** The functions unibyte-char-to-multibyte and
4105multibyte-char-to-unibyte convert between unibyte and multibyte
4106character codes, in a way that is appropriate for the current language
4107environment.
4108
4109** The functions read-event, read-char and read-char-exclusive now
4110take two optional arguments. PROMPT, if non-nil, specifies a prompt
4111string. SUPPRESS-INPUT-METHOD, if non-nil, says to disable the
4112current input method for reading this one event.
4113
4114** Two new variables print-escape-nonascii and print-escape-multibyte
4115now control whether to output certain characters as
4116backslash-sequences. print-escape-nonascii applies to single-byte
4117non-ASCII characters; print-escape-multibyte applies to multibyte
4118characters. Both of these variables are used only when printing
4119in readable fashion (prin1 uses them, princ does not).
4120\f
4121* Lisp changes in Emacs 20.3 before the Emacs Lisp Manual was published
4122
4123** Compiled Emacs Lisp files made with the modified "MBSK" version
4124of Emacs 20.2 do not work in Emacs 20.3.
4125
4126** Buffer positions are now measured in characters, as they were
4127in Emacs 19 and before. This means that (forward-char 1)
4128always increases point by 1.
4129
4130The function chars-in-region now just subtracts its arguments. It is
4131considered obsolete. The function char-boundary-p has been deleted.
4132
4133See below for additional changes relating to multibyte characters.
4134
4135** defcustom, defface and defgroup now accept the keyword `:version'.
4136Use this to specify in which version of Emacs a certain variable's
4137default value changed. For example,
4138
4139 (defcustom foo-max 34 "*Maximum number of foo's allowed."
4140 :type 'integer
4141 :group 'foo
4142 :version "20.3")
4143
79214ddf 4144 (defgroup foo-group nil "The foo group."
a933dad1
DL
4145 :version "20.3")
4146
4147If an entire new group is added or the variables in it have the
4148default values changed, then just add a `:version' to that group. It
4149is recommended that new packages added to the distribution contain a
4150`:version' in the top level group.
4151
4152This information is used to control the customize-changed-options command.
4153
4154** It is now an error to change the value of a symbol whose name
4155starts with a colon--if it is interned in the standard obarray.
4156
4157However, setting such a symbol to its proper value, which is that
4158symbol itself, is not an error. This is for the sake of programs that
4159support previous Emacs versions by explicitly setting these variables
4160to themselves.
4161
4162If you set the variable keyword-symbols-constant-flag to nil,
4163this error is suppressed, and you can set these symbols to any
4164values whatever.
4165
4166** There is a new debugger command, R.
4167It evaluates an expression like e, but saves the result
4168in the buffer *Debugger-record*.
4169
4170** Frame-local variables.
4171
4172You can now make a variable local to various frames. To do this, call
4173the function make-variable-frame-local; this enables frames to have
4174local bindings for that variable.
4175
4176These frame-local bindings are actually frame parameters: you create a
4177frame-local binding in a specific frame by calling
4178modify-frame-parameters and specifying the variable name as the
4179parameter name.
4180
4181Buffer-local bindings take precedence over frame-local bindings.
4182Thus, if the current buffer has a buffer-local binding, that binding is
4183active; otherwise, if the selected frame has a frame-local binding,
4184that binding is active; otherwise, the default binding is active.
4185
4186It would not be hard to implement window-local bindings, but it is not
4187clear that this would be very useful; windows tend to come and go in a
4188very transitory fashion, so that trying to produce any specific effect
4189through a window-local binding would not be very robust.
4190
4191** `sregexq' and `sregex' are two new functions for constructing
4192"symbolic regular expressions." These are Lisp expressions that, when
4193evaluated, yield conventional string-based regexps. The symbolic form
4194makes it easier to construct, read, and maintain complex patterns.
4195See the documentation in sregex.el.
4196
4197** parse-partial-sexp's return value has an additional element which
4198is used to pass information along if you pass it to another call to
4199parse-partial-sexp, starting its scan where the first call ended.
4200The contents of this field are not yet finalized.
4201
4202** eval-region now accepts a fourth optional argument READ-FUNCTION.
4203If it is non-nil, that function is used instead of `read'.
4204
4205** unload-feature by default removes the feature's functions from
4206known hooks to avoid trouble, but a package providing FEATURE can
4207define a hook FEATURE-unload-hook to be run by unload-feature instead.
4208
4209** read-from-minibuffer no longer returns the argument DEFAULT-VALUE
4210when the user enters empty input. It now returns the null string, as
4211it did in Emacs 19. The default value is made available in the
4212history via M-n, but it is not applied here as a default.
4213
4214The other, more specialized minibuffer-reading functions continue to
4215return the default value (not the null string) when the user enters
4216empty input.
4217
4218** The new variable read-buffer-function controls which routine to use
4219for selecting buffers. For example, if you set this variable to
4220`iswitchb-read-buffer', iswitchb will be used to read buffer names.
4221Other functions can also be used if they accept the same arguments as
4222`read-buffer' and return the selected buffer name as a string.
4223
4224** The new function read-passwd reads a password from the terminal,
4225echoing a period for each character typed. It takes three arguments:
4226a prompt string, a flag which says "read it twice to make sure", and a
4227default password to use if the user enters nothing.
4228
4229** The variable fill-nobreak-predicate gives major modes a way to
4230specify not to break a line at certain places. Its value is a
4231function which is called with no arguments, with point located at the
4232place where a break is being considered. If the function returns
4233non-nil, then the line won't be broken there.
4234
4235** window-end now takes an optional second argument, UPDATE.
4236If this is non-nil, then the function always returns an accurate
4237up-to-date value for the buffer position corresponding to the
4238end of the window, even if this requires computation.
4239
4240** other-buffer now takes an optional argument FRAME
4241which specifies which frame's buffer list to use.
4242If it is nil, that means use the selected frame's buffer list.
4243
4244** The new variable buffer-display-time, always local in every buffer,
4245holds the value of (current-time) as of the last time that a window
4246was directed to display this buffer.
4247
4248** It is now meaningful to compare two window-configuration objects
4249with `equal'. Two window-configuration objects are equal if they
4250describe equivalent arrangements of windows, in the same frame--in
4251other words, if they would give the same results if passed to
4252set-window-configuration.
4253
4254** compare-window-configurations is a new function that compares two
4255window configurations loosely. It ignores differences in saved buffer
4256positions and scrolling, and considers only the structure and sizes of
4257windows and the choice of buffers to display.
4258
4259** The variable minor-mode-overriding-map-alist allows major modes to
4260override the key bindings of a minor mode. The elements of this alist
4261look like the elements of minor-mode-map-alist: (VARIABLE . KEYMAP).
4262
4263If the VARIABLE in an element of minor-mode-overriding-map-alist has a
4264non-nil value, the paired KEYMAP is active, and totally overrides the
4265map (if any) specified for the same variable in minor-mode-map-alist.
4266
4267minor-mode-overriding-map-alist is automatically local in all buffers,
4268and it is meant to be set by major modes.
4269
4270** The function match-string-no-properties is like match-string
4271except that it discards all text properties from the result.
4272
4273** The function load-average now accepts an optional argument
4274USE-FLOATS. If it is non-nil, the load average values are returned as
4275floating point numbers, rather than as integers to be divided by 100.
4276
4277** The new variable temporary-file-directory specifies the directory
4278to use for creating temporary files. The default value is determined
4279in a reasonable way for your operating system; on GNU and Unix systems
4280it is based on the TMP and TMPDIR environment variables.
4281
4282** Menu changes
4283
4284*** easymenu.el now uses the new menu item format and supports the
4285keywords :visible and :filter. The existing keyword :keys is now
4286better supported.
4287
4288The variable `easy-menu-precalculate-equivalent-keybindings' controls
4289a new feature which calculates keyboard equivalents for the menu when
4290you define the menu. The default is t. If you rarely use menus, you
4291can set the variable to nil to disable this precalculation feature;
4292then the calculation is done only if you use the menu bar.
4293
4294*** A new format for menu items is supported.
4295
4296In a keymap, a key binding that has the format
4297 (STRING . REAL-BINDING) or (STRING HELP-STRING . REAL-BINDING)
4298defines a menu item. Now a menu item definition may also be a list that
4299starts with the symbol `menu-item'.
4300
4301The format is:
4302 (menu-item ITEM-NAME) or
4303 (menu-item ITEM-NAME REAL-BINDING . ITEM-PROPERTY-LIST)
4304where ITEM-NAME is an expression which evaluates to the menu item
4305string, and ITEM-PROPERTY-LIST has the form of a property list.
4306The supported properties include
4307
4308:enable FORM Evaluate FORM to determine whether the
4309 item is enabled.
4310:visible FORM Evaluate FORM to determine whether the
4311 item should appear in the menu.
79214ddf 4312:filter FILTER-FN
a933dad1
DL
4313 FILTER-FN is a function of one argument,
4314 which will be REAL-BINDING.
4315 It should return a binding to use instead.
4316:keys DESCRIPTION
4317 DESCRIPTION is a string that describes an equivalent keyboard
4318 binding for for REAL-BINDING. DESCRIPTION is expanded with
4319 `substitute-command-keys' before it is used.
4320:key-sequence KEY-SEQUENCE
4321 KEY-SEQUENCE is a key-sequence for an equivalent
4322 keyboard binding.
4323:key-sequence nil
4324 This means that the command normally has no
4325 keyboard equivalent.
4326:help HELP HELP is the extra help string (not currently used).
4327:button (TYPE . SELECTED)
4328 TYPE is :toggle or :radio.
4329 SELECTED is a form, to be evaluated, and its
4330 value says whether this button is currently selected.
4331
4332Buttons are at the moment only simulated by prefixes in the menu.
4333Eventually ordinary X-buttons may be supported.
4334
4335(menu-item ITEM-NAME) defines unselectable item.
4336
4337** New event types
4338
4339*** The new event type `mouse-wheel' is generated by a wheel on a
4340mouse (such as the MS Intellimouse). The event contains a delta that
4341corresponds to the amount and direction that the wheel is rotated,
4342which is typically used to implement a scroll or zoom. The format is:
4343
4344 (mouse-wheel POSITION DELTA)
4345
4346where POSITION is a list describing the position of the event in the
4347same format as a mouse-click event, and DELTA is a signed number
4348indicating the number of increments by which the wheel was rotated. A
4349negative DELTA indicates that the wheel was rotated backwards, towards
4350the user, and a positive DELTA indicates that the wheel was rotated
4351forward, away from the user.
4352
4353As of now, this event type is generated only on MS Windows.
4354
4355*** The new event type `drag-n-drop' is generated when a group of
4356files is selected in an application outside of Emacs, and then dragged
4357and dropped onto an Emacs frame. The event contains a list of
4358filenames that were dragged and dropped, which are then typically
4359loaded into Emacs. The format is:
4360
4361 (drag-n-drop POSITION FILES)
4362
4363where POSITION is a list describing the position of the event in the
4364same format as a mouse-click event, and FILES is the list of filenames
4365that were dragged and dropped.
4366
4367As of now, this event type is generated only on MS Windows.
4368
4369** Changes relating to multibyte characters.
4370
4371*** The variable enable-multibyte-characters is now read-only;
4372any attempt to set it directly signals an error. The only way
4373to change this value in an existing buffer is with set-buffer-multibyte.
4374
4375*** In a string constant, `\ ' now stands for "nothing at all". You
4376can use it to terminate a hex escape which is followed by a character
4377that could otherwise be read as part of the hex escape.
4378
4379*** String indices are now measured in characters, as they were
4380in Emacs 19 and before.
4381
4382The function chars-in-string has been deleted.
4383The function concat-chars has been renamed to `string'.
4384
4385*** The function set-buffer-multibyte sets the flag in the current
4386buffer that says whether the buffer uses multibyte representation or
4387unibyte representation. If the argument is nil, it selects unibyte
4388representation. Otherwise it selects multibyte representation.
4389
4390This function does not change the contents of the buffer, viewed
4391as a sequence of bytes. However, it does change the contents
4392viewed as characters; a sequence of two bytes which is treated as
4393one character when the buffer uses multibyte representation
4394will count as two characters using unibyte representation.
4395
4396This function sets enable-multibyte-characters to record which
4397representation is in use. It also adjusts various data in the buffer
4398(including its markers, overlays and text properties) so that they are
4399consistent with the new representation.
4400
4401*** string-make-multibyte takes a string and converts it to multibyte
4402representation. Most of the time, you don't need to care
4403about the representation, because Emacs converts when necessary;
4404however, it makes a difference when you compare strings.
4405
4406The conversion of non-ASCII characters works by adding the value of
4407nonascii-insert-offset to each character, or by translating them
4408using the table nonascii-translation-table.
4409
4410*** string-make-unibyte takes a string and converts it to unibyte
4411representation. Most of the time, you don't need to care about the
4412representation, but it makes a difference when you compare strings.
4413
4414The conversion from multibyte to unibyte representation
4415loses information; the only time Emacs performs it automatically
4416is when inserting a multibyte string into a unibyte buffer.
4417
4418*** string-as-multibyte takes a string, and returns another string
4419which contains the same bytes, but treats them as multibyte.
4420
4421*** string-as-unibyte takes a string, and returns another string
4422which contains the same bytes, but treats them as unibyte.
4423
4424*** The new function compare-strings lets you compare
4425portions of two strings. Unibyte strings are converted to multibyte,
4426so that a unibyte string can match a multibyte string.
4427You can specify whether to ignore case or not.
4428
4429*** assoc-ignore-case now uses compare-strings so that
4430it can treat unibyte and multibyte strings as equal.
4431
4432*** Regular expression operations and buffer string searches now
4433convert the search pattern to multibyte or unibyte to accord with the
4434buffer or string being searched.
4435
4436One consequence is that you cannot always use \200-\377 inside of
4437[...] to match all non-ASCII characters. This does still work when
4438searching or matching a unibyte buffer or string, but not when
4439searching or matching a multibyte string. Unfortunately, there is no
4440obvious choice of syntax to use within [...] for that job. But, what
4441you want is just to match all non-ASCII characters, the regular
4442expression [^\0-\177] works for it.
4443
4444*** Structure of coding system changed.
4445
4446All coding systems (including aliases and subsidiaries) are named
4447by symbols; the symbol's `coding-system' property is a vector
4448which defines the coding system. Aliases share the same vector
4449as the principal name, so that altering the contents of this
4450vector affects the principal name and its aliases. You can define
4451your own alias name of a coding system by the function
4452define-coding-system-alias.
4453
4454The coding system definition includes a property list of its own. Use
4455the new functions `coding-system-get' and `coding-system-put' to
4456access such coding system properties as post-read-conversion,
4457pre-write-conversion, character-translation-table-for-decode,
4458character-translation-table-for-encode, mime-charset, and
4459safe-charsets. For instance, (coding-system-get 'iso-latin-1
4460'mime-charset) gives the corresponding MIME-charset parameter
4461`iso-8859-1'.
4462
4463Among the coding system properties listed above, safe-charsets is new.
4464The value of this property is a list of character sets which this
4465coding system can correctly encode and decode. For instance:
4466(coding-system-get 'iso-latin-1 'safe-charsets) => (ascii latin-iso8859-1)
4467
4468Here, "correctly encode" means that the encoded character sets can
4469also be handled safely by systems other than Emacs as far as they
4470are capable of that coding system. Though, Emacs itself can encode
4471the other character sets and read it back correctly.
4472
4473*** The new function select-safe-coding-system can be used to find a
4474proper coding system for encoding the specified region or string.
4475This function requires a user interaction.
4476
4477*** The new functions find-coding-systems-region and
4478find-coding-systems-string are helper functions used by
4479select-safe-coding-system. They return a list of all proper coding
4480systems to encode a text in some region or string. If you don't want
4481a user interaction, use one of these functions instead of
4482select-safe-coding-system.
4483
4484*** The explicit encoding and decoding functions, such as
4485decode-coding-region and encode-coding-string, now set
4486last-coding-system-used to reflect the actual way encoding or decoding
4487was done.
4488
4489*** The new function detect-coding-with-language-environment can be
4490used to detect a coding system of text according to priorities of
4491coding systems used by some specific language environment.
4492
4493*** The functions detect-coding-region and detect-coding-string always
4494return a list if the arg HIGHEST is nil. Thus, if only ASCII
4495characters are found, they now return a list of single element
4496`undecided' or its subsidiaries.
4497
4498*** The new functions coding-system-change-eol-conversion and
4499coding-system-change-text-conversion can be used to get a different
4500coding system than what specified only in how end-of-line or text is
4501converted.
4502
4503*** The new function set-selection-coding-system can be used to set a
4504coding system for communicating with other X clients.
4505
4506*** The function `map-char-table' now passes as argument only valid
4507character codes, plus generic characters that stand for entire
4508character sets or entire subrows of a character set. In other words,
4509each time `map-char-table' calls its FUNCTION argument, the key value
4510either will be a valid individual character code, or will stand for a
4511range of characters.
4512
4513*** The new function `char-valid-p' can be used for checking whether a
4514Lisp object is a valid character code or not.
4515
4516*** The new function `charset-after' returns a charset of a character
4517in the current buffer at position POS.
4518
4519*** Input methods are now implemented using the variable
4520input-method-function. If this is non-nil, its value should be a
4521function; then, whenever Emacs reads an input event that is a printing
4522character with no modifier bits, it calls that function, passing the
4523event as an argument. Often this function will read more input, first
4524binding input-method-function to nil.
4525
4526The return value should be a list of the events resulting from input
4527method processing. These events will be processed sequentially as
4528input, before resorting to unread-command-events. Events returned by
4529the input method function are not passed to the input method function,
4530not even if they are printing characters with no modifier bits.
4531
4532The input method function is not called when reading the second and
4533subsequent events of a key sequence.
4534
4535*** You can customize any language environment by using
4536set-language-environment-hook and exit-language-environment-hook.
4537
4538The hook `exit-language-environment-hook' should be used to undo
4539customizations that you made with set-language-environment-hook. For
4540instance, if you set up a special key binding for a specific language
4541environment by set-language-environment-hook, you should set up
4542exit-language-environment-hook to restore the normal key binding.
4543\f
4544* Changes in Emacs 20.1
4545
4546** Emacs has a new facility for customization of its many user
4547options. It is called M-x customize. With this facility you can look
4548at the many user options in an organized way; they are grouped into a
4549tree structure.
4550
4551M-x customize also knows what sorts of values are legitimate for each
4552user option and ensures that you don't use invalid values.
4553
4554With M-x customize, you can set options either for the present Emacs
4555session or permanently. (Permanent settings are stored automatically
4556in your .emacs file.)
4557
4558** Scroll bars are now on the left side of the window.
4559You can change this with M-x customize-option scroll-bar-mode.
4560
4561** The mode line no longer includes the string `Emacs'.
4562This makes more space in the mode line for other information.
4563
4564** When you select a region with the mouse, it is highlighted
4565immediately afterward. At that time, if you type the DELETE key, it
4566kills the region.
4567
4568The BACKSPACE key, and the ASCII character DEL, do not do this; they
4569delete the character before point, as usual.
4570
4571** In an incremental search the whole current match is highlighted
4572on terminals which support this. (You can disable this feature
4573by setting search-highlight to nil.)
4574
4575** In the minibuffer, in some cases, you can now use M-n to
4576insert the default value into the minibuffer as text. In effect,
4577the default value (if the minibuffer routines know it) is tacked
4578onto the history "in the future". (The more normal use of the
4579history list is to use M-p to insert minibuffer input used in the
4580past.)
4581
4582** In Text mode, now only blank lines separate paragraphs.
4583This makes it possible to get the full benefit of Adaptive Fill mode
4584in Text mode, and other modes derived from it (such as Mail mode).
4585TAB in Text mode now runs the command indent-relative; this
4586makes a practical difference only when you use indented paragraphs.
4587
4588As a result, the old Indented Text mode is now identical to Text mode,
4589and is an alias for it.
4590
4591If you want spaces at the beginning of a line to start a paragraph,
4592use the new mode, Paragraph Indent Text mode.
4593
4594** Scrolling changes
4595
4596*** Scroll commands to scroll a whole screen now preserve the screen
4597position of the cursor, if scroll-preserve-screen-position is non-nil.
4598
4599In this mode, if you scroll several screens back and forth, finishing
4600on the same screen where you started, the cursor goes back to the line
4601where it started.
4602
4603*** If you set scroll-conservatively to a small number, then when you
4604move point a short distance off the screen, Emacs will scroll the
4605screen just far enough to bring point back on screen, provided that
4606does not exceed `scroll-conservatively' lines.
4607
4608*** The new variable scroll-margin says how close point can come to the
4609top or bottom of a window. It is a number of screen lines; if point
4610comes within that many lines of the top or bottom of the window, Emacs
4611recenters the window.
4612
4613** International character set support (MULE)
4614
4615Emacs now supports a wide variety of international character sets,
4616including European variants of the Latin alphabet, as well as Chinese,
4617Devanagari (Hindi and Marathi), Ethiopian, Greek, IPA, Japanese,
4618Korean, Lao, Russian, Thai, Tibetan, and Vietnamese scripts. These
4619features have been merged from the modified version of Emacs known as
4620MULE (for "MULti-lingual Enhancement to GNU Emacs")
4621
4622Users of these scripts have established many more-or-less standard
4623coding systems for storing files. Emacs uses a single multibyte
4624character encoding within Emacs buffers; it can translate from a wide
4625variety of coding systems when reading a file and can translate back
4626into any of these coding systems when saving a file.
4627
4628Keyboards, even in the countries where these character sets are used,
4629generally don't have keys for all the characters in them. So Emacs
4630supports various "input methods", typically one for each script or
4631language, to make it possible to type them.
4632
4633The Emacs internal multibyte encoding represents a non-ASCII
4634character as a sequence of bytes in the range 0200 through 0377.
4635
4636The new prefix key C-x RET is used for commands that pertain
4637to multibyte characters, coding systems, and input methods.
4638
4639You can disable multibyte character support as follows:
4640
4641 (setq-default enable-multibyte-characters nil)
4642
4643Calling the function standard-display-european turns off multibyte
4644characters, unless you specify a non-nil value for the second
4645argument, AUTO. This provides compatibility for people who are
4646already using standard-display-european to continue using unibyte
4647characters for their work until they want to change.
4648
4649*** Input methods
4650
4651An input method is a kind of character conversion which is designed
4652specifically for interactive input. In Emacs, typically each language
4653has its own input method (though sometimes several languages which use
4654the same characters can share one input method). Some languages
4655support several input methods.
4656
4657The simplest kind of input method works by mapping ASCII letters into
4658another alphabet. This is how the Greek and Russian input methods
4659work.
4660
4661A more powerful technique is composition: converting sequences of
4662characters into one letter. Many European input methods use
4663composition to produce a single non-ASCII letter from a sequence which
4664consists of a letter followed by diacritics. For example, a' is one
4665sequence of two characters that might be converted into a single
4666letter.
4667
4668The input methods for syllabic scripts typically use mapping followed
4669by conversion. The input methods for Thai and Korean work this way.
4670First, letters are mapped into symbols for particular sounds or tone
4671marks; then, sequences of these which make up a whole syllable are
4672mapped into one syllable sign--most often a "composite character".
4673
4674None of these methods works very well for Chinese and Japanese, so
4675they are handled specially. First you input a whole word using
4676phonetic spelling; then, after the word is in the buffer, Emacs
4677converts it into one or more characters using a large dictionary.
4678
4679Since there is more than one way to represent a phonetically spelled
4680word using Chinese characters, Emacs can only guess which one to use;
4681typically these input methods give you a way to say "guess again" if
4682the first guess is wrong.
4683
4684*** The command C-x RET m (toggle-enable-multibyte-characters)
4685turns multibyte character support on or off for the current buffer.
4686
4687If multibyte character support is turned off in a buffer, then each
4688byte is a single character, even codes 0200 through 0377--exactly as
4689they did in Emacs 19.34. This includes the features for support for
4690the European characters, ISO Latin-1 and ISO Latin-2.
4691
4692However, there is no need to turn off multibyte character support to
4693use ISO Latin-1 or ISO Latin-2; the Emacs multibyte character set
4694includes all the characters in these character sets, and Emacs can
4695translate automatically to and from either one.
4696
4697*** Visiting a file in unibyte mode.
4698
4699Turning off multibyte character support in the buffer after visiting a
4700file with multibyte code conversion will display the multibyte
4701sequences already in the buffer, byte by byte. This is probably not
4702what you want.
4703
4704If you want to edit a file of unibyte characters (Latin-1, for
4705example), you can do it by specifying `no-conversion' as the coding
4706system when reading the file. This coding system also turns off
4707multibyte characters in that buffer.
4708
4709If you turn off multibyte character support entirely, this turns off
4710character conversion as well.
4711
4712*** Displaying international characters on X Windows.
4713
4714A font for X typically displays just one alphabet or script.
4715Therefore, displaying the entire range of characters Emacs supports
4716requires using many fonts.
4717
4718Therefore, Emacs now supports "fontsets". Each fontset is a
4719collection of fonts, each assigned to a range of character codes.
4720
4721A fontset has a name, like a font. Individual fonts are defined by
4722the X server; fontsets are defined within Emacs itself. But once you
4723have defined a fontset, you can use it in a face or a frame just as
4724you would use a font.
4725
4726If a fontset specifies no font for a certain character, or if it
4727specifies a font that does not exist on your system, then it cannot
4728display that character. It will display an empty box instead.
4729
4730The fontset height and width are determined by the ASCII characters
4731(that is, by the font in the fontset which is used for ASCII
4732characters). If another font in the fontset has a different height,
4733or the wrong width, then characters assigned to that font are clipped,
4734and displayed within a box if highlight-wrong-size-font is non-nil.
4735
4736*** Defining fontsets.
4737
4738Emacs does not use any fontset by default. Its default font is still
4739chosen as in previous versions. You can tell Emacs to use a fontset
4740with the `-fn' option or the `Font' X resource.
4741
4742Emacs creates a standard fontset automatically according to the value
4743of standard-fontset-spec. This fontset's short name is
4744`fontset-standard'. Bold, italic, and bold-italic variants of the
4745standard fontset are created automatically.
4746
4747If you specify a default ASCII font with the `Font' resource or `-fn'
4748argument, a fontset is generated from it. This works by replacing the
4749FOUNDARY, FAMILY, ADD_STYLE, and AVERAGE_WIDTH fields of the font name
4750with `*' then using this to specify a fontset. This fontset's short
4751name is `fontset-startup'.
4752
4753Emacs checks resources of the form Fontset-N where N is 0, 1, 2...
4754The resource value should have this form:
4755 FONTSET-NAME, [CHARSET-NAME:FONT-NAME]...
4756FONTSET-NAME should have the form of a standard X font name, except:
4757 * most fields should be just the wild card "*".
4758 * the CHARSET_REGISTRY field should be "fontset"
4759 * the CHARSET_ENCODING field can be any nickname of the fontset.
4760The construct CHARSET-NAME:FONT-NAME can be repeated any number
4761of times; each time specifies the font for one character set.
4762CHARSET-NAME should be the name name of a character set, and
4763FONT-NAME should specify an actual font to use for that character set.
4764
4765Each of these fontsets has an alias which is made from the
4766last two font name fields, CHARSET_REGISTRY and CHARSET_ENCODING.
4767You can refer to the fontset by that alias or by its full name.
4768
4769For any character sets that you don't mention, Emacs tries to choose a
4770font by substituting into FONTSET-NAME. For instance, with the
4771following resource,
4772 Emacs*Fontset-0: -*-fixed-medium-r-normal-*-24-*-*-*-*-*-fontset-24
4773the font for ASCII is generated as below:
4774 -*-fixed-medium-r-normal-*-24-*-ISO8859-1
4775Here is the substitution rule:
4776 Change CHARSET_REGISTRY and CHARSET_ENCODING to that of the charset
4777 defined in the variable x-charset-registries. For instance, ASCII has
4778 the entry (ascii . "ISO8859-1") in this variable. Then, reduce
4779 sequences of wild cards -*-...-*- with a single wildcard -*-.
4780 (This is to prevent use of auto-scaled fonts.)
4781
4782The function which processes the fontset resource value to create the
4783fontset is called create-fontset-from-fontset-spec. You can also call
4784that function explicitly to create a fontset.
4785
4786With the X resource Emacs.Font, you can specify a fontset name just
4787like an actual font name. But be careful not to specify a fontset
4788name in a wildcard resource like Emacs*Font--that tries to specify the
4789fontset for other purposes including menus, and they cannot handle
4790fontsets.
4791
4792*** The command M-x set-language-environment sets certain global Emacs
4793defaults for a particular choice of language.
4794
4795Selecting a language environment typically specifies a default input
4796method and which coding systems to recognize automatically when
4797visiting files. However, it does not try to reread files you have
4798already visited; the text in those buffers is not affected. The
4799language environment may also specify a default choice of coding
4800system for new files that you create.
4801
4802It makes no difference which buffer is current when you use
4803set-language-environment, because these defaults apply globally to the
4804whole Emacs session.
4805
4806For example, M-x set-language-environment RET Latin-1 RET
4807chooses the Latin-1 character set. In the .emacs file, you can do this
4808with (set-language-environment "Latin-1").
4809
4810*** The command C-x RET f (set-buffer-file-coding-system)
4811specifies the file coding system for the current buffer. This
4812specifies what sort of character code translation to do when saving
4813the file. As an argument, you must specify the name of one of the
4814coding systems that Emacs supports.
4815
4816*** The command C-x RET c (universal-coding-system-argument)
4817lets you specify a coding system when you read or write a file.
4818This command uses the minibuffer to read a coding system name.
4819After you exit the minibuffer, the specified coding system
4820is used for *the immediately following command*.
4821
4822So if the immediately following command is a command to read or
4823write a file, it uses the specified coding system for that file.
4824
4825If the immediately following command does not use the coding system,
4826then C-x RET c ultimately has no effect.
4827
4828For example, C-x RET c iso-8859-1 RET C-x C-f temp RET
4829visits the file `temp' treating it as ISO Latin-1.
4830
4831*** You can specify the coding system for a file using the -*-
4832construct. Include `coding: CODINGSYSTEM;' inside the -*-...-*-
4833to specify use of coding system CODINGSYSTEM. You can also
4834specify the coding system in a local variable list at the end
4835of the file.
4836
4837*** The command C-x RET t (set-terminal-coding-system) specifies
4838the coding system for terminal output. If you specify a character
4839code for terminal output, all characters output to the terminal are
4840translated into that character code.
4841
4842This feature is useful for certain character-only terminals built in
4843various countries to support the languages of those countries.
4844
4845By default, output to the terminal is not translated at all.
4846
4847*** The command C-x RET k (set-keyboard-coding-system) specifies
4848the coding system for keyboard input.
4849
4850Character code translation of keyboard input is useful for terminals
4851with keys that send non-ASCII graphic characters--for example,
4852some terminals designed for ISO Latin-1 or subsets of it.
4853
4854By default, keyboard input is not translated at all.
4855
4856Character code translation of keyboard input is similar to using an
4857input method, in that both define sequences of keyboard input that
4858translate into single characters. However, input methods are designed
4859to be convenient for interactive use, while the code translations are
4860designed to work with terminals.
4861
4862*** The command C-x RET p (set-buffer-process-coding-system)
4863specifies the coding system for input and output to a subprocess.
4864This command applies to the current buffer; normally, each subprocess
4865has its own buffer, and thus you can use this command to specify
4866translation to and from a particular subprocess by giving the command
4867in the corresponding buffer.
4868
4869By default, process input and output are not translated at all.
4870
4871*** The variable file-name-coding-system specifies the coding system
4872to use for encoding file names before operating on them.
4873It is also used for decoding file names obtained from the system.
4874
4875*** The command C-\ (toggle-input-method) activates or deactivates
4876an input method. If no input method has been selected before, the
4877command prompts for you to specify the language and input method you
4878want to use.
4879
4880C-u C-\ (select-input-method) lets you switch to a different input
4881method. C-h C-\ (or C-h I) describes the current input method.
4882
4883*** Some input methods remap the keyboard to emulate various keyboard
4884layouts commonly used for particular scripts. How to do this
4885remapping properly depends on your actual keyboard layout. To specify
4886which layout your keyboard has, use M-x quail-set-keyboard-layout.
4887
4888*** The command C-h C (describe-coding-system) displays
4889the coding systems currently selected for various purposes, plus
4890related information.
4891
4892*** The command C-h h (view-hello-file) displays a file called
4893HELLO, which has examples of text in many languages, using various
4894scripts.
4895
4896*** The command C-h L (describe-language-support) displays
4897information about the support for a particular language.
4898You specify the language as an argument.
4899
4900*** The mode line now contains a letter or character that identifies
4901the coding system used in the visited file. It normally follows the
4902first dash.
4903
4904A dash indicates the default state of affairs: no code conversion
4905(except CRLF => newline if appropriate). `=' means no conversion
4906whatsoever. The ISO 8859 coding systems are represented by digits
49071 through 9. Other coding systems are represented by letters:
4908
4909 A alternativnyj (Russian)
4910 B big5 (Chinese)
4911 C cn-gb-2312 (Chinese)
4912 C iso-2022-cn (Chinese)
4913 D in-is13194-devanagari (Indian languages)
4914 E euc-japan (Japanese)
4915 I iso-2022-cjk or iso-2022-ss2 (Chinese, Japanese, Korean)
4916 J junet (iso-2022-7) or old-jis (iso-2022-jp-1978-irv) (Japanese)
4917 K euc-korea (Korean)
4918 R koi8 (Russian)
4919 Q tibetan
4920 S shift_jis (Japanese)
4921 T lao
4922 T tis620 (Thai)
4923 V viscii or vscii (Vietnamese)
4924 i iso-2022-lock (Chinese, Japanese, Korean)
4925 k iso-2022-kr (Korean)
4926 v viqr (Vietnamese)
4927 z hz (Chinese)
4928
4929When you are using a character-only terminal (not a window system),
4930two additional characters appear in between the dash and the file
4931coding system. These two characters describe the coding system for
4932keyboard input, and the coding system for terminal output.
4933
4934*** The new variable rmail-file-coding-system specifies the code
4935conversion to use for RMAIL files. The default value is nil.
4936
4937When you read mail with Rmail, each message is decoded automatically
4938into Emacs' internal format. This has nothing to do with
4939rmail-file-coding-system. That variable controls reading and writing
4940Rmail files themselves.
4941
4942*** The new variable sendmail-coding-system specifies the code
4943conversion for outgoing mail. The default value is nil.
4944
4945Actually, there are three different ways of specifying the coding system
4946for sending mail:
4947
4948- If you use C-x RET f in the mail buffer, that takes priority.
4949- Otherwise, if you set sendmail-coding-system non-nil, that specifies it.
4950- Otherwise, the default coding system for new files is used,
4951 if that is non-nil. That comes from your language environment.
4952- Otherwise, Latin-1 is used.
4953
4954*** The command C-h t (help-with-tutorial) accepts a prefix argument
4955to specify the language for the tutorial file. Currently, English,
4956Japanese, Korean and Thai are supported. We welcome additional
4957translations.
4958
4959** An easy new way to visit a file with no code or format conversion
4960of any kind: Use M-x find-file-literally. There is also a command
4961insert-file-literally which inserts a file into the current buffer
4962without any conversion.
4963
4964** C-q's handling of octal character codes is changed.
4965You can now specify any number of octal digits.
4966RET terminates the digits and is discarded;
4967any other non-digit terminates the digits and is then used as input.
4968
4969** There are new commands for looking up Info documentation for
4970functions, variables and file names used in your programs.
4971
4972Type M-x info-lookup-symbol to look up a symbol in the buffer at point.
4973Type M-x info-lookup-file to look up a file in the buffer at point.
4974
4975Precisely which Info files are used to look it up depends on the major
4976mode. For example, in C mode, the GNU libc manual is used.
4977
4978** M-TAB in most programming language modes now runs the command
4979complete-symbol. This command performs completion on the symbol name
4980in the buffer before point.
4981
4982With a numeric argument, it performs completion based on the set of
4983symbols documented in the Info files for the programming language that
4984you are using.
4985
4986With no argument, it does completion based on the current tags tables,
4987just like the old binding of M-TAB (complete-tag).
4988
4989** File locking works with NFS now.
4990
4991The lock file for FILENAME is now a symbolic link named .#FILENAME,
4992in the same directory as FILENAME.
4993
4994This means that collision detection between two different machines now
4995works reasonably well; it also means that no file server or directory
4996can become a bottleneck.
4997
4998The new method does have drawbacks. It means that collision detection
4999does not operate when you edit a file in a directory where you cannot
5000create new files. Collision detection also doesn't operate when the
5001file server does not support symbolic links. But these conditions are
5002rare, and the ability to have collision detection while using NFS is
5003so useful that the change is worth while.
5004
5005When Emacs or a system crashes, this may leave behind lock files which
5006are stale. So you may occasionally get warnings about spurious
5007collisions. When you determine that the collision is spurious, just
5008tell Emacs to go ahead anyway.
5009
5010** If you wish to use Show Paren mode to display matching parentheses,
5011it is no longer sufficient to load paren.el. Instead you must call
5012show-paren-mode.
5013
5014** If you wish to use Delete Selection mode to replace a highlighted
5015selection when you insert new text, it is no longer sufficient to load
5016delsel.el. Instead you must call the function delete-selection-mode.
5017
5018** If you wish to use Partial Completion mode to complete partial words
5019within symbols or filenames, it is no longer sufficient to load
5020complete.el. Instead you must call the function partial-completion-mode.
5021
5022** If you wish to use uniquify to rename buffers for you,
5023it is no longer sufficient to load uniquify.el. You must also
5024set uniquify-buffer-name-style to one of the non-nil legitimate values.
5025
5026** Changes in View mode.
5027
5028*** Several new commands are available in View mode.
5029Do H in view mode for a list of commands.
5030
5031*** There are two new commands for entering View mode:
5032view-file-other-frame and view-buffer-other-frame.
5033
5034*** Exiting View mode does a better job of restoring windows to their
5035previous state.
5036
5037*** New customization variable view-scroll-auto-exit. If non-nil,
5038scrolling past end of buffer makes view mode exit.
5039
5040*** New customization variable view-exits-all-viewing-windows. If
5041non-nil, view-mode will at exit restore all windows viewing buffer,
5042not just the selected window.
5043
5044*** New customization variable view-read-only. If non-nil, visiting a
5045read-only file automatically enters View mode, and toggle-read-only
5046turns View mode on or off.
5047
5048*** New customization variable view-remove-frame-by-deleting controls
5049how to remove a not needed frame at view mode exit. If non-nil,
5050delete the frame, if nil make an icon of it.
5051
5052** C-x v l, the command to print a file's version control log,
5053now positions point at the entry for the file's current branch version.
5054
5055** C-x v =, the command to compare a file with the last checked-in version,
5056has a new feature. If the file is currently not locked, so that it is
5057presumably identical to the last checked-in version, the command now asks
5058which version to compare with.
5059
5060** When using hideshow.el, incremental search can temporarily show hidden
79214ddf 5061blocks if a match is inside the block.
a933dad1
DL
5062
5063The block is hidden again if the search is continued and the next match
5064is outside the block. By customizing the variable
5065isearch-hide-immediately you can choose to hide all the temporarily
5066shown blocks only when exiting from incremental search.
5067
5068By customizing the variable hs-isearch-open you can choose what kind
5069of blocks to temporarily show during isearch: comment blocks, code
5070blocks, all of them or none.
5071
5072** The new command C-x 4 0 (kill-buffer-and-window) kills the
5073current buffer and deletes the selected window. It asks for
5074confirmation first.
5075
5076** C-x C-w, which saves the buffer into a specified file name,
5077now changes the major mode according to that file name.
5078However, the mode will not be changed if
5079(1) a local variables list or the `-*-' line specifies a major mode, or
5080(2) the current major mode is a "special" mode,
5081 not suitable for ordinary files, or
5082(3) the new file name does not particularly specify any mode.
5083
5084This applies to M-x set-visited-file-name as well.
5085
5086However, if you set change-major-mode-with-file-name to nil, then
5087these commands do not change the major mode.
5088
5089** M-x occur changes.
5090
5091*** If the argument to M-x occur contains upper case letters,
5092it performs a case-sensitive search.
5093
5094*** In the *Occur* buffer made by M-x occur,
5095if you type g or M-x revert-buffer, this repeats the search
5096using the same regular expression and the same buffer as before.
5097
5098** In Transient Mark mode, the region in any one buffer is highlighted
5099in just one window at a time. At first, it is highlighted in the
5100window where you set the mark. The buffer's highlighting remains in
5101that window unless you select to another window which shows the same
5102buffer--then the highlighting moves to that window.
5103
5104** The feature to suggest key bindings when you use M-x now operates
5105after the command finishes. The message suggesting key bindings
5106appears temporarily in the echo area. The previous echo area contents
5107come back after a few seconds, in case they contain useful information.
5108
5109** Each frame now independently records the order for recently
5110selected buffers, so that the default for C-x b is now based on the
5111buffers recently selected in the selected frame.
5112
5113** Outline mode changes.
5114
5115*** Outline mode now uses overlays (this is the former noutline.el).
5116
5117*** Incremental searches skip over invisible text in Outline mode.
5118
5119** When a minibuffer window is active but not the selected window, if
5120you try to use the minibuffer, you used to get a nested minibuffer.
5121Now, this not only gives an error, it also cancels the minibuffer that
5122was already active.
5123
5124The motive for this change is so that beginning users do not
5125unknowingly move away from minibuffers, leaving them active, and then
5126get confused by it.
5127
5128If you want to be able to have recursive minibuffers, you must
5129set enable-recursive-minibuffers to non-nil.
5130
5131** Changes in dynamic abbrevs.
5132
5133*** Expanding dynamic abbrevs with M-/ is now smarter about case
5134conversion. If the expansion has mixed case not counting the first
5135character, and the abbreviation matches the beginning of the expansion
5136including case, then the expansion is copied verbatim.
5137
5138The expansion is also copied verbatim if the abbreviation itself has
5139mixed case. And using SPC M-/ to copy an additional word always
5140copies it verbatim except when the previous copied word is all caps.
5141
5142*** The values of `dabbrev-case-replace' and `dabbrev-case-fold-search'
5143are no longer Lisp expressions. They have simply three possible
5144values.
5145
5146`dabbrev-case-replace' has these three values: nil (don't preserve
5147case), t (do), or `case-replace' (do like M-x query-replace).
5148`dabbrev-case-fold-search' has these three values: nil (don't ignore
5149case), t (do), or `case-fold-search' (do like search).
5150
5151** Minibuffer history lists are truncated automatically now to a
5152certain length. The variable history-length specifies how long they
5153can be. The default value is 30.
5154
5155** Changes in Mail mode.
5156
5157*** The key C-x m no longer runs the `mail' command directly.
5158Instead, it runs the command `compose-mail', which invokes the mail
5159composition mechanism you have selected with the variable
5160`mail-user-agent'. The default choice of user agent is
5161`sendmail-user-agent', which gives behavior compatible with the old
5162behavior.
5163
5164C-x 4 m now runs compose-mail-other-window, and C-x 5 m runs
5165compose-mail-other-frame.
5166
5167*** While composing a reply to a mail message, from Rmail, you can use
5168the command C-c C-r to cite just the region from the message you are
5169replying to. This copies the text which is the selected region in the
5170buffer that shows the original message.
5171
5172*** The command C-c C-i inserts a file at the end of the message,
5173with separator lines around the contents.
5174
5175*** The command M-x expand-mail-aliases expands all mail aliases
5176in suitable mail headers. Emacs automatically extracts mail alias
5177definitions from your mail alias file (e.g., ~/.mailrc). You do not
5178need to expand mail aliases yourself before sending mail.
5179
5180*** New features in the mail-complete command.
5181
5182**** The mail-complete command now inserts the user's full name,
5183for local users or if that is known. The variable mail-complete-style
5184controls the style to use, and whether to do this at all.
5185Its values are like those of mail-from-style.
5186
5187**** The variable mail-passwd-command lets you specify a shell command
5188to run to fetch a set of password-entries that add to the ones in
5189/etc/passwd.
5190
5191**** The variable mail-passwd-file now specifies a list of files to read
5192to get the list of user ids. By default, one file is used:
5193/etc/passwd.
5194
5195** You can "quote" a file name to inhibit special significance of
5196special syntax, by adding `/:' to the beginning. Thus, if you have a
5197directory named `/foo:', you can prevent it from being treated as a
5198reference to a remote host named `foo' by writing it as `/:/foo:'.
5199
5200Emacs uses this new construct automatically when necessary, such as
5201when you start it with a working directory whose name might otherwise
5202be taken to be magic.
5203
5204** There is a new command M-x grep-find which uses find to select
5205files to search through, and grep to scan them. The output is
5206available in a Compile mode buffer, as with M-x grep.
5207
5208M-x grep now uses the -e option if the grep program supports that.
5209(-e prevents problems if the search pattern starts with a dash.)
5210
5211** In Dired, the & command now flags for deletion the files whose names
5212suggest they are probably not needed in the long run.
5213
5214In Dired, * is now a prefix key for mark-related commands.
5215
5216new key dired.el binding old key
5217------- ---------------- -------
5218 * c dired-change-marks c
5219 * m dired-mark m
5220 * * dired-mark-executables * (binding deleted)
5221 * / dired-mark-directories / (binding deleted)
5222 * @ dired-mark-symlinks @ (binding deleted)
5223 * u dired-unmark u
5224 * DEL dired-unmark-backward DEL
5225 * ? dired-unmark-all-files M-C-?
5226 * ! dired-unmark-all-marks
5227 * % dired-mark-files-regexp % m
5228 * C-n dired-next-marked-file M-}
5229 * C-p dired-prev-marked-file M-{
5230
5231** Rmail changes.
5232
5233*** When Rmail cannot convert your incoming mail into Babyl format, it
5234saves the new mail in the file RMAILOSE.n, where n is an integer
5235chosen to make a unique name. This way, Rmail will not keep crashing
5236each time you run it.
5237
5238*** In Rmail, the variable rmail-summary-line-count-flag now controls
5239whether to include the line count in the summary. Non-nil means yes.
5240
5241*** In Rmail summary buffers, d and C-d (the commands to delete
5242messages) now take repeat counts as arguments. A negative argument
5243means to move in the opposite direction.
5244
5245*** In Rmail, the t command now takes an optional argument which lets
5246you specify whether to show the message headers in full or pruned.
5247
5248*** In Rmail, the new command w (rmail-output-body-to-file) writes
5249just the body of the current message into a file, without the headers.
5250It takes the file name from the message subject, by default, but you
5251can edit that file name in the minibuffer before it is actually used
5252for output.
5253
5254** Gnus changes.
5255
5256*** nntp.el has been totally rewritten in an asynchronous fashion.
5257
79214ddf
FP
5258*** Article prefetching functionality has been moved up into
5259Gnus.
a933dad1 5260
79214ddf 5261*** Scoring can now be performed with logical operators like
a933dad1
DL
5262`and', `or', `not', and parent redirection.
5263
5264*** Article washing status can be displayed in the
5265article mode line.
5266
5267*** gnus.el has been split into many smaller files.
5268
5269*** Suppression of duplicate articles based on Message-ID.
5270
5271(setq gnus-suppress-duplicates t)
5272
5273*** New variables for specifying what score and adapt files
5274are to be considered home score and adapt files. See
5275`gnus-home-score-file' and `gnus-home-adapt-files'.
5276
5277*** Groups can inherit group parameters from parent topics.
5278
5279*** Article editing has been revamped and is now usable.
5280
5281*** Signatures can be recognized in more intelligent fashions.
5282See `gnus-signature-separator' and `gnus-signature-limit'.
5283
5284*** Summary pick mode has been made to look more nn-like.
5285Line numbers are displayed and the `.' command can be
5286used to pick articles.
5287
5288*** Commands for moving the .newsrc.eld from one server to
5289another have been added.
5290
5291 `M-x gnus-change-server'
5292
5293*** A way to specify that "uninteresting" fields be suppressed when
5294generating lines in buffers.
5295
5296*** Several commands in the group buffer can be undone with
5297`M-C-_'.
5298
5299*** Scoring can be done on words using the new score type `w'.
5300
5301*** Adaptive scoring can be done on a Subject word-by-word basis:
5302
5303 (setq gnus-use-adaptive-scoring '(word))
5304
5305*** Scores can be decayed.
79214ddf 5306
a933dad1
DL
5307 (setq gnus-decay-scores t)
5308
5309*** Scoring can be performed using a regexp on the Date header. The
5310Date is normalized to compact ISO 8601 format first.
5311
5312*** A new command has been added to remove all data on articles from
5313the native server.
5314
5315 `M-x gnus-group-clear-data-on-native-groups'
5316
5317*** A new command for reading collections of documents
5318(nndoc with nnvirtual on top) has been added -- `M-C-d'.
5319
5320*** Process mark sets can be pushed and popped.
5321
5322*** A new mail-to-news backend makes it possible to post
5323even when the NNTP server doesn't allow posting.
5324
5325*** A new backend for reading searches from Web search engines
5326(DejaNews, Alta Vista, InReference) has been added.
5327
5328 Use the `G w' command in the group buffer to create such
5329 a group.
5330
5331*** Groups inside topics can now be sorted using the standard
5332sorting functions, and each topic can be sorted independently.
5333
5334 See the commands under the `T S' submap.
5335
5336*** Subsets of the groups can be sorted independently.
5337
5338 See the commands under the `G P' submap.
5339
5340*** Cached articles can be pulled into the groups.
79214ddf 5341
a933dad1
DL
5342 Use the `Y c' command.
5343
5344*** Score files are now applied in a more reliable order.
5345
5346*** Reports on where mail messages end up can be generated.
5347
5348 `M-x nnmail-split-history'
5349
5350*** More hooks and functions have been added to remove junk
5351from incoming mail before saving the mail.
79214ddf 5352
a933dad1
DL
5353 See `nnmail-prepare-incoming-header-hook'.
5354
5355*** The nnml mail backend now understands compressed article files.
5356
5357*** To enable Gnus to read/post multi-lingual articles, you must execute
5358the following code, for instance, in your .emacs.
5359
5360 (add-hook 'gnus-startup-hook 'gnus-mule-initialize)
5361
5362Then, when you start Gnus, it will decode non-ASCII text automatically
5363and show appropriate characters. (Note: if you are using gnus-mime
5364from the SEMI package, formerly known as TM, you should NOT add this
5365hook to gnus-startup-hook; gnus-mime has its own method of handling
5366this issue.)
5367
5368Since it is impossible to distinguish all coding systems
5369automatically, you may need to specify a choice of coding system for a
5370particular news group. This can be done by:
5371
5372 (gnus-mule-add-group NEWSGROUP 'CODING-SYSTEM)
5373
5374Here NEWSGROUP should be a string which names a newsgroup or a tree
5375of newsgroups. If NEWSGROUP is "XXX.YYY", all news groups under
5376"XXX.YYY" (including "XXX.YYY.ZZZ") will use the specified coding
5377system. CODING-SYSTEM specifies which coding system to use (for both
5378for reading and posting).
5379
5380CODING-SYSTEM can also be a cons cell of the form
5381 (READ-CODING-SYSTEM . POST-CODING-SYSTEM)
5382Then READ-CODING-SYSTEM is used when you read messages from the
5383newsgroups, while POST-CODING-SYSTEM is used when you post messages
5384there.
5385
5386Emacs knows the right coding systems for certain newsgroups by
5387default. Here are some of these default settings:
5388
5389 (gnus-mule-add-group "fj" 'iso-2022-7)
5390 (gnus-mule-add-group "alt.chinese.text" 'hz-gb-2312)
5391 (gnus-mule-add-group "alt.hk" 'hz-gb-2312)
5392 (gnus-mule-add-group "alt.chinese.text.big5" 'cn-big5)
5393 (gnus-mule-add-group "soc.culture.vietnamese" '(nil . viqr))
5394
5395When you reply by mail to an article, these settings are ignored;
5396the mail is encoded according to sendmail-coding-system, as usual.
5397
5398** CC mode changes.
5399
5400*** If you edit primarily one style of C (or C++, Objective-C, Java)
5401code, you may want to make the CC Mode style variables have global
5402values so that you can set them directly in your .emacs file. To do
5403this, set c-style-variables-are-local-p to nil in your .emacs file.
5404Note that this only takes effect if you do it *before* cc-mode.el is
5405loaded.
5406
5407If you typically edit more than one style of C (or C++, Objective-C,
79214ddf 5408Java) code in a single Emacs session, you may want to make the CC Mode
a933dad1 5409style variables have buffer local values. By default, all buffers
79214ddf
FP
5410share the same style variable settings; to make them buffer local, set
5411c-style-variables-are-local-p to t in your .emacs file. Note that you
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DL
5412must do this *before* CC Mode is loaded.
5413
5414*** The new variable c-indentation-style holds the C style name
5415of the current buffer.
5416
5417*** The variable c-block-comments-indent-p has been deleted, because
5418it is no longer necessary. C mode now handles all the supported styles
5419of block comments, with no need to say which one you will use.
5420
5421*** There is a new indentation style "python", which specifies the C
5422style that the Python developers like.
5423
5424*** There is a new c-cleanup-list option: brace-elseif-brace.
5425This says to put ...} else if (...) {... on one line,
5426just as brace-else-brace says to put ...} else {... on one line.
5427
5428** VC Changes [new]
5429
5430** In vc-retrieve-snapshot (C-x v r), if you don't specify a snapshot
5431name, it retrieves the *latest* versions of all files in the current
5432directory and its subdirectories (aside from files already locked).
5433
5434This feature is useful if your RCS directory is a link to a common
5435master directory, and you want to pick up changes made by other
5436developers.
5437
5438You can do the same thing for an individual file by typing C-u C-x C-q
5439RET in a buffer visiting that file.
5440
5441*** VC can now handle files under CVS that are being "watched" by
5442other developers. Such files are made read-only by CVS. To get a
5443writable copy, type C-x C-q in a buffer visiting such a file. VC then
5444calls "cvs edit", which notifies the other developers of it.
5445
5446*** vc-version-diff (C-u C-x v =) now suggests reasonable defaults for
5447version numbers, based on the current state of the file.
5448
5449** Calendar changes.
5450
5451A new function, list-holidays, allows you list holidays or subclasses
5452of holidays for ranges of years. Related menu items allow you do this
5453for the year of the selected date, or the following/previous years.
5454
5455** ps-print changes
5456
79214ddf 5457There are some new user variables for customizing the page layout.
a933dad1
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5458
5459*** Paper size, paper orientation, columns
5460
5461The variable `ps-paper-type' determines the size of paper ps-print
5462formats for; it should contain one of the symbols:
5463`a4' `a3' `letter' `legal' `letter-small' `tabloid'
5464`ledger' `statement' `executive' `a4small' `b4' `b5'
5465It defaults to `letter'.
5466If you need other sizes, see the variable `ps-page-dimensions-database'.
5467
5468The variable `ps-landscape-mode' determines the orientation
79214ddf 5469of the printing on the page. nil, the default, means "portrait" mode,
a933dad1
DL
5470non-nil means "landscape" mode.
5471
5472The variable `ps-number-of-columns' must be a positive integer.
5473It determines the number of columns both in landscape and portrait mode.
79214ddf 5474It defaults to 1.
a933dad1
DL
5475
5476*** Horizontal layout
5477
5478The horizontal layout is determined by the variables
5479`ps-left-margin', `ps-inter-column', and `ps-right-margin'.
5480All are measured in points.
5481
5482*** Vertical layout
5483
5484The vertical layout is determined by the variables
5485`ps-bottom-margin', `ps-top-margin', and `ps-header-offset'.
5486All are measured in points.
5487
5488*** Headers
5489
5490If the variable `ps-print-header' is nil, no header is printed. Then
5491`ps-header-offset' is not relevant and `ps-top-margin' represents the
5492margin above the text.
5493
79214ddf 5494If the variable `ps-print-header-frame' is non-nil, a gaudy
a933dad1
DL
5495framing box is printed around the header.
5496
5497The contents of the header are determined by `ps-header-lines',
5498`ps-show-n-of-n', `ps-left-header' and `ps-right-header'.
5499
79214ddf
FP
5500The height of the header is determined by `ps-header-line-pad',
5501`ps-header-font-family', `ps-header-title-font-size' and
a933dad1
DL
5502`ps-header-font-size'.
5503
5504*** Font managing
5505
5506The variable `ps-font-family' determines which font family is to be
5507used for ordinary text. Its value must be a key symbol in the alist
5508`ps-font-info-database'. You can add other font families by adding
5509elements to this alist.
5510
79214ddf 5511The variable `ps-font-size' determines the size of the font
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DL
5512for ordinary text. It defaults to 8.5 points.
5513
5514** hideshow changes.
5515
5516*** now supports hiding of blocks of single line comments (like // for
79214ddf 5517C++, ; for lisp).
a933dad1
DL
5518
5519*** Support for java-mode added.
5520
5521*** When doing `hs-hide-all' it is now possible to also hide the comments
5522in the file if `hs-hide-comments-when-hiding-all' is set.
5523
5524*** The new function `hs-hide-initial-comment' hides the the comments at
5525the beginning of the files. Finally those huge RCS logs don't stay in your
5526way! This is run by default when entering the `hs-minor-mode'.
5527
5528*** Now uses overlays instead of `selective-display', so is more
5529robust and a lot faster.
5530
79214ddf 5531*** A block beginning can span multiple lines.
a933dad1
DL
5532
5533*** The new variable `hs-show-hidden-short-form' if t, directs hideshow
5534to show only the beginning of a block when it is hidden. See the
5535documentation for more details.
5536
5537** Changes in Enriched mode.
5538
5539*** When you visit a file in enriched-mode, Emacs will make sure it is
5540filled to the current fill-column. This behavior is now independent
5541of the size of the window. When you save the file, the fill-column in
5542use is stored as well, so that the whole buffer need not be refilled
5543the next time unless the fill-column is different.
5544
5545*** use-hard-newlines is now a minor mode. When it is enabled, Emacs
5546distinguishes between hard and soft newlines, and treats hard newlines
5547as paragraph boundaries. Otherwise all newlines inserted are marked
5548as soft, and paragraph boundaries are determined solely from the text.
5549
5550** Font Lock mode
5551
5552*** Custom support
5553
5554The variables font-lock-face-attributes, font-lock-display-type and
5555font-lock-background-mode are now obsolete; the recommended way to specify the
5556faces to use for Font Lock mode is with M-x customize-group on the new custom
5557group font-lock-highlighting-faces. If you set font-lock-face-attributes in
5558your ~/.emacs file, Font Lock mode will respect its value. However, you should
5559consider converting from setting that variable to using M-x customize.
5560
5561You can still use X resources to specify Font Lock face appearances.
5562
5563*** Maximum decoration
5564
5565Fontification now uses the maximum level of decoration supported by
5566default. Previously, fontification used a mode-specific default level
5567of decoration, which is typically the minimum level of decoration
5568supported. You can set font-lock-maximum-decoration to nil
5569to get the old behavior.
5570
5571*** New support
5572
5573Support is now provided for Java, Objective-C, AWK and SIMULA modes.
5574
5575Note that Font Lock mode can be turned on without knowing exactly what modes
5576support Font Lock mode, via the command global-font-lock-mode.
5577
5578*** Configurable support
5579
5580Support for C, C++, Objective-C and Java can be more easily configured for
5581additional types and classes via the new variables c-font-lock-extra-types,
5582c++-font-lock-extra-types, objc-font-lock-extra-types and, you guessed it,
5583java-font-lock-extra-types. These value of each of these variables should be a
5584list of regexps matching the extra type names. For example, the default value
5585of c-font-lock-extra-types is ("\\sw+_t") which means fontification follows the
5586convention that C type names end in _t. This results in slower fontification.
5587
5588Of course, you can change the variables that specify fontification in whatever
5589way you wish, typically by adding regexps. However, these new variables make
5590it easier to make specific and common changes for the fontification of types.
5591
5592*** Adding highlighting patterns to existing support
5593
5594You can use the new function font-lock-add-keywords to add your own
5595highlighting patterns, such as for project-local or user-specific constructs,
5596for any mode.
5597
5598For example, to highlight `FIXME:' words in C comments, put:
5599
5600 (font-lock-add-keywords 'c-mode '(("\\<FIXME:" 0 font-lock-warning-face t)))
5601
5602in your ~/.emacs.
5603
5604*** New faces
5605
5606Font Lock now defines two new faces, font-lock-builtin-face and
5607font-lock-warning-face. These are intended to highlight builtin keywords,
5608distinct from a language's normal keywords, and objects that should be brought
5609to user attention, respectively. Various modes now use these new faces.
5610
5611*** Changes to fast-lock support mode
5612
5613The fast-lock package, one of the two Font Lock support modes, can now process
5614cache files silently. You can use the new variable fast-lock-verbose, in the
5615same way as font-lock-verbose, to control this feature.
5616
5617*** Changes to lazy-lock support mode
5618
5619The lazy-lock package, one of the two Font Lock support modes, can now fontify
5620according to the true syntactic context relative to other lines. You can use
5621the new variable lazy-lock-defer-contextually to control this feature. If
5622non-nil, changes to the buffer will cause subsequent lines in the buffer to be
5623refontified after lazy-lock-defer-time seconds of idle time. If nil, then only
5624the modified lines will be refontified; this is the same as the previous Lazy
5625Lock mode behaviour and the behaviour of Font Lock mode.
5626
5627This feature is useful in modes where strings or comments can span lines.
5628For example, if a string or comment terminating character is deleted, then if
5629this feature is enabled subsequent lines in the buffer will be correctly
5630refontified to reflect their new syntactic context. Previously, only the line
5631containing the deleted character would be refontified and you would have to use
5632the command M-g M-g (font-lock-fontify-block) to refontify some lines.
5633
5634As a consequence of this new feature, two other variables have changed:
5635
5636Variable `lazy-lock-defer-driven' is renamed `lazy-lock-defer-on-scrolling'.
5637Variable `lazy-lock-defer-time' can now only be a time, i.e., a number.
5638Buffer modes for which on-the-fly deferral applies can be specified via the
5639new variable `lazy-lock-defer-on-the-fly'.
5640
5641If you set these variables in your ~/.emacs, then you may have to change those
5642settings.
5643
5644** Ada mode changes.
5645
5646*** There is now better support for using find-file.el with Ada mode.
5647If you switch between spec and body, the cursor stays in the same
5648procedure (modulo overloading). If a spec has no body file yet, but
5649you try to switch to its body file, Ada mode now generates procedure
5650stubs.
5651
5652*** There are two new commands:
5653 - `ada-make-local' : invokes gnatmake on the current buffer
5654 - `ada-check-syntax' : check syntax of current buffer.
5655
5656The user options `ada-compiler-make', `ada-make-options',
5657`ada-language-version', `ada-compiler-syntax-check', and
79214ddf 5658`ada-compile-options' are used within these commands.
a933dad1
DL
5659
5660*** Ada mode can now work with Outline minor mode. The outline level
5661is calculated from the indenting, not from syntactic constructs.
5662Outlining does not work if your code is not correctly indented.
5663
5664*** The new function `ada-gnat-style' converts the buffer to the style of
5665formatting used in GNAT. It places two blanks after a comment start,
5666places one blank between a word end and an opening '(', and puts one
5667space between a comma and the beginning of a word.
5668
5669** Scheme mode changes.
5670
5671*** Scheme mode indentation now uses many of the facilities of Lisp
5672mode; therefore, the variables to customize it are the variables used
5673for Lisp mode which have names starting with `lisp-'. The variables
5674with names starting with `scheme-' which used to do this no longer
5675have any effect.
5676
5677If you want to use different indentation for Scheme and Lisp, this is
5678still possible, but now you must do it by adding a hook to
5679scheme-mode-hook, which could work by setting the `lisp-' indentation
5680variables as buffer-local variables.
5681
5682*** DSSSL mode is a variant of Scheme mode, for editing DSSSL scripts.
5683Use M-x dsssl-mode.
5684
133c9e59
GM
5685** Changes to the emacsclient program
5686
875c1439
GM
5687*** If a socket can't be found, and environment variables LOGNAME or
5688USER are set, emacsclient now looks for a socket based on the UID
5689associated with the name. That is an emacsclient running as root
5690can connect to an Emacs server started by a non-root user.
5691
133c9e59 5692*** The emacsclient program now accepts an option --no-wait which tells
a933dad1
DL
5693it to return immediately without waiting for you to "finish" the
5694buffer in Emacs.
5695
133c9e59
GM
5696*** The new option --alternate-editor allows to specify an editor to
5697use if Emacs is not running. The environment variable
5698ALTERNATE_EDITOR can be used for the same effect; the command line
5699option takes precedence.
5700
a933dad1
DL
5701** M-x eldoc-mode enables a minor mode in which the echo area
5702constantly shows the parameter list for function being called at point
5703(in Emacs Lisp and Lisp Interaction modes only).
5704
5705** C-x n d now runs the new command narrow-to-defun,
5706which narrows the accessible parts of the buffer to just
5707the current defun.
5708
5709** Emacs now handles the `--' argument in the standard way; all
5710following arguments are treated as ordinary file names.
5711
5712** On MSDOS and Windows, the bookmark file is now called _emacs.bmk,
5713and the saved desktop file is now called _emacs.desktop (truncated if
5714necessary).
5715
5716** When you kill a buffer that visits a file,
5717if there are any registers that save positions in the file,
5718these register values no longer become completely useless.
5719If you try to go to such a register with C-x j, then you are
5720asked whether to visit the file again. If you say yes,
5721it visits the file and then goes to the same position.
5722
5723** When you visit a file that changes frequently outside Emacs--for
5724example, a log of output from a process that continues to run--it may
5725be useful for Emacs to revert the file without querying you whenever
5726you visit the file afresh with C-x C-f.
5727
5728You can request this behavior for certain files by setting the
5729variable revert-without-query to a list of regular expressions. If a
5730file's name matches any of these regular expressions, find-file and
5731revert-buffer revert the buffer without asking for permission--but
5732only if you have not edited the buffer text yourself.
5733
5734** set-default-font has been renamed to set-frame-font
5735since it applies only to the current frame.
5736
5737** In TeX mode, you can use the variable tex-main-file to specify the
5738file for tex-file to run TeX on. (By default, tex-main-file is nil,
5739and tex-file runs TeX on the current visited file.)
5740
5741This is useful when you are editing a document that consists of
5742multiple files. In each of the included files, you can set up a local
5743variable list which specifies the top-level file of your document for
5744tex-main-file. Then tex-file will run TeX on the whole document
5745instead of just the file you are editing.
5746
5747** RefTeX mode
5748
5749RefTeX mode is a new minor mode with special support for \label, \ref
5750and \cite macros in LaTeX documents. RefTeX distinguishes labels of
5751different environments (equation, figure, ...) and has full support for
5752multifile documents. To use it, select a buffer with a LaTeX document and
5753turn the mode on with M-x reftex-mode. Here are the main user commands:
5754
79214ddf 5755C-c ( reftex-label
a933dad1
DL
5756 Creates a label semi-automatically. RefTeX is context sensitive and
5757 knows which kind of label is needed.
5758
5759C-c ) reftex-reference
5760 Offers in a menu all labels in the document, along with context of the
5761 label definition. The selected label is referenced as \ref{LABEL}.
5762
5763C-c [ reftex-citation
5764 Prompts for a regular expression and displays a list of matching BibTeX
5765 database entries. The selected entry is cited with a \cite{KEY} macro.
5766
5767C-c & reftex-view-crossref
5768 Views the cross reference of a \ref or \cite command near point.
5769
5770C-c = reftex-toc
5771 Shows a table of contents of the (multifile) document. From there you
5772 can quickly jump to every section.
79214ddf 5773
a933dad1
DL
5774Under X, RefTeX installs a "Ref" menu in the menu bar, with additional
5775commands. Press `?' to get help when a prompt mentions this feature.
5776Full documentation and customization examples are in the file
5777reftex.el. You can use the finder to view the file documentation:
5778C-h p --> tex --> reftex.el
5779
5780** Changes in BibTeX mode.
5781
5782*** Info documentation is now available.
5783
5784*** Don't allow parentheses in string constants anymore. This confused
5785both the BibTeX program and Emacs BibTeX mode.
5786
5787*** Renamed variable bibtex-mode-user-optional-fields to
5788bibtex-user-optional-fields.
5789
5790*** Removed variable bibtex-include-OPTannote
5791(use bibtex-user-optional-fields instead).
5792
5793*** New interactive functions to copy and kill fields and complete
5794entries to the BibTeX kill ring, from where they can be yanked back by
5795appropriate functions.
5796
5797*** New interactive functions for repositioning and marking of
5798entries. They are bound by default to M-C-l and M-C-h.
5799
5800*** New hook bibtex-clean-entry-hook. It is called after entry has
5801been cleaned.
5802
5803*** New variable bibtex-field-delimiters, which replaces variables
5804bibtex-field-{left|right}-delimiter.
5805
5806*** New variable bibtex-entry-delimiters to determine how entries
5807shall be delimited.
5808
5809*** Allow preinitialization of fields. See documentation of
5810bibtex-user-optional-fields, bibtex-entry-field-alist, and
5811bibtex-include-OPTkey for details.
5812
5813*** Book and InBook entries require either an author or an editor
5814field. This is now supported by bibtex.el. Alternative fields are
5815prefixed with `ALT'.
5816
5817*** New variable bibtex-entry-format, which replaces variable
5818bibtex-clean-entry-zap-empty-opts and allows specification of many
5819formatting options performed on cleaning an entry (see variable
5820documentation).
5821
5822*** Even more control on how automatic keys are generated. See
5823documentation of bibtex-generate-autokey for details. Transcriptions
5824for foreign languages other than German are now handled, too.
5825
5826*** New boolean user option bibtex-comma-after-last-field to decide if
5827comma should be inserted at end of last field.
5828
5829*** New boolean user option bibtex-align-at-equal-sign to determine if
5830alignment should be made at left side of field contents or at equal
5831signs. New user options to control entry layout (e.g. indentation).
5832
5833*** New function bibtex-fill-entry to realign entries.
5834
5835*** New function bibtex-reformat to reformat region or buffer.
5836
5837*** New function bibtex-convert-alien to convert a BibTeX database
5838from alien sources.
5839
5840*** New function bibtex-complete-key (similar to bibtex-complete-string)
5841to complete prefix to a key defined in buffer. Mainly useful in
5842crossref entries.
5843
5844*** New function bibtex-count-entries to count entries in buffer or
5845region.
5846
5847*** Added support for imenu.
5848
5849*** The function `bibtex-validate' now checks current region instead
5850of buffer if mark is active. Now it shows all errors of buffer in a
5851`compilation mode' buffer. You can use the normal commands (e.g.
5852`next-error') for compilation modes to jump to errors.
5853
5854*** New variable `bibtex-string-file-path' to determine where the files
5855from `bibtex-string-files' are searched.
5856
5857** Iso Accents mode now supports Latin-3 as an alternative.
5858
30a009a5 5859** The command next-error now opens blocks hidden by hideshow.
047f434a 5860
a933dad1
DL
5861** The function using-unix-filesystems has been replaced by the
5862functions add-untranslated-filesystem and remove-untranslated-filesystem.
5863Each of these functions takes the name of a drive letter or directory
5864as an argument.
5865
5866When a filesystem is added as untranslated, all files on it are read
5867and written in binary mode (no cr/lf translation is performed).
5868
5869** browse-url changes
5870
5871*** New methods for: Grail (browse-url-generic), MMM (browse-url-mmm),
5872Lynx in a separate xterm (browse-url-lynx-xterm) or in an Emacs window
5873(browse-url-lynx-emacs), remote W3 (browse-url-w3-gnudoit), generic
5874non-remote-controlled browsers (browse-url-generic) and associated
5875customization variables.
5876
5877*** New commands `browse-url-of-region' and `browse-url'.
5878
5879*** URLs marked up with <URL:...> (RFC1738) work if broken across
5880lines. Browsing methods can be associated with URL regexps
5881(e.g. mailto: URLs) via `browse-url-browser-function'.
5882
5883** Changes in Ediff
5884
5885*** Clicking Mouse-2 on a brief command description in Ediff control panel
5886pops up the Info file for this command.
5887
5888*** There is now a variable, ediff-autostore-merges, which controls whether
5889the result of a merge is saved in a file. By default, this is done only when
5890merge is done from a session group (eg, when merging files in two different
5891directories).
5892
5893*** Since Emacs 19.31 (this hasn't been announced before), Ediff can compare
5894and merge groups of files residing in different directories, or revisions of
5895files in the same directory.
5896
5897*** Since Emacs 19.31, Ediff can apply multi-file patches interactively.
5898The patches must be in the context format or GNU unified format. (The bug
5899related to the GNU format has now been fixed.)
5900
5901** Changes in Viper
5902
5903*** The startup file is now .viper instead of .vip
79214ddf 5904*** All variable/function names have been changed to start with viper-
a933dad1
DL
5905 instead of vip-.
5906*** C-\ now simulates the meta-key in all Viper states.
79214ddf 5907*** C-z in Insert state now escapes to Vi for the duration of the next
a933dad1
DL
5908Viper command. In Vi and Insert states, C-z behaves as before.
5909*** C-c \ escapes to Vi for one command if Viper is in Insert or Emacs states.
5910*** _ is no longer the meta-key in Vi state.
5911*** The variable viper-insert-state-cursor-color can be used to change cursor
5912color when Viper is in insert state.
5913*** If search lands the cursor near the top or the bottom of the window,
5914Viper pulls the window up or down to expose more context. The variable
5915viper-adjust-window-after-search controls this behavior.
5916
5917** Etags changes.
5918
5919*** In C, C++, Objective C and Java, Etags tags global variables by
5920default. The resulting tags files are inflated by 30% on average.
5921Use --no-globals to turn this feature off. Etags can also tag
5922variables which are members of structure-like constructs, but it does
5923not by default. Use --members to turn this feature on.
5924
5925*** C++ member functions are now recognized as tags.
5926
5927*** Java is tagged like C++. In addition, "extends" and "implements"
5928constructs are tagged. Files are recognised by the extension .java.
5929
5930*** Etags can now handle programs written in Postscript. Files are
5931recognised by the extensions .ps and .pdb (Postscript with C syntax).
5932In Postscript, tags are lines that start with a slash.
5933
5934*** Etags now handles Objective C and Objective C++ code. The usual C and
5935C++ tags are recognized in these languages; in addition, etags
5936recognizes special Objective C syntax for classes, class categories,
5937methods and protocols.
5938
5939*** Etags also handles Cobol. Files are recognised by the extension
5940.cobol. The tagged lines are those containing a word that begins in
5941column 8 and ends in a full stop, i.e. anything that could be a
5942paragraph name.
5943
5944*** Regexps in Etags now support intervals, as in ed or grep. The syntax of
5945an interval is \{M,N\}, and it means to match the preceding expression
5946at least M times and as many as N times.
5947
5948** The format for specifying a custom format for time-stamp to insert
5949in files has changed slightly.
5950
5951With the new enhancements to the functionality of format-time-string,
5952time-stamp-format will change to be eventually compatible with it.
5953This conversion is being done in two steps to maintain compatibility
5954with old time-stamp-format values.
5955
5956In the new scheme, alternate case is signified by the number-sign
5957(`#') modifier, rather than changing the case of the format character.
5958This feature is as yet incompletely implemented for compatibility
5959reasons.
5960
5961In the old time-stamp-format, all numeric fields defaulted to their
5962natural width. (With format-time-string, each format has a
5963fixed-width default.) In this version, you can specify the colon
5964(`:') modifier to a numeric conversion to mean "give me the historical
5965time-stamp-format width default." Do not use colon if you are
5966specifying an explicit width, as in "%02d".
5967
5968Numbers are no longer truncated to the requested width, except in the
5969case of "%02y", which continues to give a two-digit year. Digit
5970truncation probably wasn't being used for anything else anyway.
5971
5972The new formats will work with old versions of Emacs. New formats are
5973being recommended now to allow time-stamp-format to change in the
5974future to be compatible with format-time-string. The new forms being
5975recommended now will continue to work then.
5976
5977See the documentation string for the variable time-stamp-format for
5978details.
5979
5980** There are some additional major modes:
5981
5982dcl-mode, for editing VMS DCL files.
5983m4-mode, for editing files of m4 input.
5984meta-mode, for editing MetaFont and MetaPost source files.
5985
5986** In Shell mode, the command shell-copy-environment-variable lets you
5987copy the value of a specified environment variable from the subshell
5988into Emacs.
5989
5990** New Lisp packages include:
5991
5992*** battery.el displays battery status for laptops.
5993
5994*** M-x bruce (named after Lenny Bruce) is a program that might
5995be used for adding some indecent words to your email.
5996
5997*** M-x crisp-mode enables an emulation for the CRiSP editor.
5998
5999*** M-x dirtrack arranges for better tracking of directory changes
6000in shell buffers.
6001
6002*** The new library elint.el provides for linting of Emacs Lisp code.
6003See the documentation for `elint-initialize', `elint-current-buffer'
6004and `elint-defun'.
6005
6006*** M-x expand-add-abbrevs defines a special kind of abbrev which is
6007meant for programming constructs. These abbrevs expand like ordinary
6008ones, when you type SPC, but only at the end of a line and not within
6009strings or comments.
6010
6011These abbrevs can act as templates: you can define places within an
6012abbrev for insertion of additional text. Once you expand the abbrev,
6013you can then use C-x a p and C-x a n to move back and forth to these
6014insertion points. Thus you can conveniently insert additional text
6015at these points.
6016
6017*** filecache.el remembers the location of files so that you
6018can visit them by short forms of their names.
6019
6020*** find-func.el lets you find the definition of the user-loaded
6021Emacs Lisp function at point.
6022
6023*** M-x handwrite converts text to a "handwritten" picture.
6024
6025*** M-x iswitchb-buffer is a command for switching to a buffer, much like
6026switch-buffer, but it reads the argument in a more helpful way.
6027
6028*** M-x landmark implements a neural network for landmark learning.
6029
6030*** M-x locate provides a convenient interface to the `locate' program.
6031
6032*** M4 mode is a new mode for editing files of m4 input.
6033
6034*** mantemp.el creates C++ manual template instantiations
6035from the GCC error messages which indicate which instantiations are needed.
6036
6037*** mouse-copy.el provides a one-click copy and move feature.
6038You can drag a region with M-mouse-1, and it is automatically
6039inserted at point. M-Shift-mouse-1 deletes the text from its
6040original place after inserting the copy.
6041
6042*** mouse-drag.el lets you do scrolling by dragging Mouse-2
6043on the buffer.
6044
6045You click the mouse and move; that distance either translates into the
6046velocity to scroll (with mouse-drag-throw) or the distance to scroll
6047(with mouse-drag-drag). Horizontal scrolling is enabled when needed.
6048
6049Enable mouse-drag with:
6050 (global-set-key [down-mouse-2] 'mouse-drag-throw)
6051-or-
6052 (global-set-key [down-mouse-2] 'mouse-drag-drag)
6053
6054*** mspools.el is useful for determining which mail folders have
6055mail waiting to be read in them. It works with procmail.
6056
6057*** Octave mode is a major mode for editing files of input for Octave.
6058It comes with a facility for communicating with an Octave subprocess.
6059
6060*** ogonek
6061
6062The ogonek package provides functions for changing the coding of
6063Polish diacritic characters in buffers. Codings known from various
6064platforms are supported such as ISO8859-2, Mazovia, IBM Latin2, and
6065TeX. For example, you can change the coding from Mazovia to
6066ISO8859-2. Another example is a change of coding from ISO8859-2 to
6067prefix notation (in which `/a' stands for the aogonek character, for
6068instance) and vice versa.
6069
6070To use this package load it using
6071 M-x load-library [enter] ogonek
6072Then, you may get an explanation by calling one of
79214ddf 6073 M-x ogonek-jak -- in Polish
a933dad1
DL
6074 M-x ogonek-how -- in English
6075The info specifies the commands and variables provided as well as the
6076ways of customization in `.emacs'.
6077
6078*** Interface to ph.
6079
6080Emacs provides a client interface to CCSO Nameservers (ph/qi)
6081
6082The CCSO nameserver is used in many universities to provide directory
6083services about people. ph.el provides a convenient Emacs interface to
6084these servers.
6085
6086*** uce.el is useful for replying to unsolicited commercial email.
6087
6088*** vcursor.el implements a "virtual cursor" feature.
6089You can move the virtual cursor with special commands
6090while the real cursor does not move.
6091
6092*** webjump.el is a "hot list" package which you can set up
6093for visiting your favorite web sites.
6094
6095*** M-x winner-mode is a minor mode which saves window configurations,
6096so you can move back to other configurations that you have recently used.
6097
6098** movemail change
6099
6100Movemail no longer needs to be installed setuid root in order for POP
6101mail retrieval to function properly. This is because it no longer
6102supports the RPOP (reserved-port POP) protocol; instead, it uses the
6103user's POP password to authenticate to the mail server.
6104
6105This change was made earlier, but not reported in NEWS before.
6106\f
6107* Emacs 20.1 changes for MS-DOS and MS-Windows.
6108
6109** Changes in handling MS-DOS/MS-Windows text files.
6110
6111Emacs handles three different conventions for representing
6112end-of-line: CRLF for MSDOS, LF for Unix and GNU, and CR (used on the
6113Macintosh). Emacs determines which convention is used in a specific
6114file based on the contents of that file (except for certain special
6115file names), and when it saves the file, it uses the same convention.
6116
6117To save the file and change the end-of-line convention, you can use
6118C-x RET f (set-buffer-file-coding-system) to specify a different
6119coding system for the buffer. Then, when you save the file, the newly
6120specified coding system will take effect. For example, to save with
6121LF, specify undecided-unix (or some other ...-unix coding system); to
6122save with CRLF, specify undecided-dos.
6123\f
6124* Lisp Changes in Emacs 20.1
6125
6126** Byte-compiled files made with Emacs 20 will, in general, work in
6127Emacs 19 as well, as long as the source code runs in Emacs 19. And
6128vice versa: byte-compiled files made with Emacs 19 should also run in
6129Emacs 20, as long as the program itself works in Emacs 20.
6130
6131** Windows-specific functions and variables have been renamed
6132to start with w32- instead of win32-.
6133
6134In hacker language, calling something a "win" is a form of praise. We
6135don't want to praise a non-free Microsoft system, so we don't call it
6136"win".
6137
6138** Basic Lisp changes
6139
6140*** A symbol whose name starts with a colon now automatically
6141evaluates to itself. Therefore such a symbol can be used as a constant.
6142
6143*** The defined purpose of `defconst' has been changed. It should now
6144be used only for values that should not be changed whether by a program
6145or by the user.
6146
6147The actual behavior of defconst has not been changed.
6148
6149*** There are new macros `when' and `unless'
6150
6151(when CONDITION BODY...) is short for (if CONDITION (progn BODY...))
6152(unless CONDITION BODY...) is short for (if CONDITION nil BODY...)
6153
6154*** Emacs now defines functions caar, cadr, cdar and cddr with their
6155usual Lisp meanings. For example, caar returns the car of the car of
6156its argument.
6157
6158*** equal, when comparing strings, now ignores their text properties.
6159
6160*** The new function `functionp' tests whether an object is a function.
6161
6162*** arrayp now returns t for char-tables and bool-vectors.
6163
6164*** Certain primitives which use characters (as integers) now get an
6165error if the integer is not a valid character code. These primitives
6166include insert-char, char-to-string, and the %c construct in the
6167`format' function.
6168
6169*** The `require' function now insists on adding a suffix, either .el
6170or .elc, to the file name. Thus, (require 'foo) will not use a file
6171whose name is just foo. It insists on foo.el or foo.elc.
6172
6173*** The `autoload' function, when the file name does not contain
6174either a directory name or the suffix .el or .elc, insists on
6175adding one of these suffixes.
6176
6177*** string-to-number now takes an optional second argument BASE
6178which specifies the base to use when converting an integer.
79214ddf 6179If BASE is omitted, base 10 is used.
a933dad1
DL
6180
6181We have not implemented other radices for floating point numbers,
6182because that would be much more work and does not seem useful.
6183
6184*** substring now handles vectors as well as strings.
6185
6186*** The Common Lisp function eql is no longer defined normally.
6187You must load the `cl' library to define it.
6188
6189*** The new macro `with-current-buffer' lets you evaluate an expression
6190conveniently with a different current buffer. It looks like this:
6191
6192 (with-current-buffer BUFFER BODY-FORMS...)
6193
6194BUFFER is the expression that says which buffer to use.
6195BODY-FORMS say what to do in that buffer.
6196
6197*** The new primitive `save-current-buffer' saves and restores the
6198choice of current buffer, like `save-excursion', but without saving or
6199restoring the value of point or the mark. `with-current-buffer'
6200works using `save-current-buffer'.
6201
6202*** The new macro `with-temp-file' lets you do some work in a new buffer and
6203write the output to a specified file. Like `progn', it returns the value
6204of the last form.
6205
6206*** The new macro `with-temp-buffer' lets you do some work in a new buffer,
6207which is discarded after use. Like `progn', it returns the value of the
6208last form. If you wish to return the buffer contents, use (buffer-string)
6209as the last form.
6210
6211*** The new function split-string takes a string, splits it at certain
6212characters, and returns a list of the substrings in between the
6213matches.
6214
6215For example, (split-string "foo bar lose" " +") returns ("foo" "bar" "lose").
6216
6217*** The new macro with-output-to-string executes some Lisp expressions
6218with standard-output set up so that all output feeds into a string.
6219Then it returns that string.
6220
6221For example, if the current buffer name is `foo',
6222
6223(with-output-to-string
6224 (princ "The buffer is ")
6225 (princ (buffer-name)))
6226
6227returns "The buffer is foo".
6228
6229** Non-ASCII characters are now supported, if enable-multibyte-characters
6230is non-nil.
6231
6232These characters have character codes above 256. When inserted in the
6233buffer or stored in a string, they are represented as multibyte
6234characters that occupy several buffer positions each.
6235
6236*** When enable-multibyte-characters is non-nil, a single character in
6237a buffer or string can be two or more bytes (as many as four).
6238
6239Buffers and strings are still made up of unibyte elements;
6240character positions and string indices are always measured in bytes.
6241Therefore, moving forward one character can increase the buffer
6242position by 2, 3 or 4. The function forward-char moves by whole
6243characters, and therefore is no longer equivalent to
6244 (lambda (n) (goto-char (+ (point) n))).
6245
6246ASCII characters (codes 0 through 127) are still single bytes, always.
6247Sequences of byte values 128 through 255 are used to represent
6248non-ASCII characters. These sequences are called "multibyte
6249characters".
6250
6251The first byte of a multibyte character is always in the range 128
6252through 159 (octal 0200 through 0237). These values are called
6253"leading codes". The second and subsequent bytes are always in the
6254range 160 through 255 (octal 0240 through 0377). The first byte, the
6255leading code, determines how many bytes long the sequence is.
6256
6257*** The function forward-char moves over characters, and therefore
6258(forward-char 1) may increase point by more than 1 if it moves over a
6259multibyte character. Likewise, delete-char always deletes a
6260character, which may be more than one buffer position.
6261
6262This means that some Lisp programs, which assume that a character is
6263always one buffer position, need to be changed.
6264
6265However, all ASCII characters are always one buffer position.
79214ddf 6266
a933dad1
DL
6267*** The regexp [\200-\377] no longer matches all non-ASCII characters,
6268because when enable-multibyte-characters is non-nil, these characters
6269have codes that are not in the range octal 200 to octal 377. However,
6270the regexp [^\000-\177] does match all non-ASCII characters,
6271guaranteed.
6272
6273*** The function char-boundary-p returns non-nil if position POS is
6274between two characters in the buffer (not in the middle of a
6275character).
6276
6277When the value is non-nil, it says what kind of character follows POS:
6278
6279 0 if POS is at an ASCII character or at the end of range,
6280 1 if POS is before a 2-byte length multi-byte form,
6281 2 if POS is at a head of 3-byte length multi-byte form,
6282 3 if POS is at a head of 4-byte length multi-byte form,
6283 4 if POS is at a head of multi-byte form of a composite character.
6284
6285*** The function char-bytes returns how many bytes the character CHAR uses.
6286
6287*** Strings can contain multibyte characters. The function
6288`length' returns the string length counting bytes, which may be
6289more than the number of characters.
6290
6291You can include a multibyte character in a string constant by writing
6292it literally. You can also represent it with a hex escape,
6293\xNNNNNNN..., using as many digits as necessary. Any character which
6294is not a valid hex digit terminates this construct. If you want to
6295follow it with a character that is a hex digit, write backslash and
6296newline in between; that will terminate the hex escape.
6297
6298*** The function concat-chars takes arguments which are characters
6299and returns a string containing those characters.
6300
6301*** The function sref access a multibyte character in a string.
6302(sref STRING INDX) returns the character in STRING at INDEX. INDEX
6303counts from zero. If INDEX is at a position in the middle of a
6304character, sref signals an error.
6305
6306*** The function chars-in-string returns the number of characters
6307in a string. This is less than the length of the string, if the
6308string contains multibyte characters (the length counts bytes).
6309
6310*** The function chars-in-region returns the number of characters
6311in a region from BEG to END. This is less than (- END BEG) if the
6312region contains multibyte characters (the length counts bytes).
6313
6314*** The function string-to-list converts a string to a list of
6315the characters in it. string-to-vector converts a string
6316to a vector of the characters in it.
6317
6318*** The function store-substring alters part of the contents
6319of a string. You call it as follows:
6320
6321 (store-substring STRING IDX OBJ)
6322
6323This says to alter STRING, by storing OBJ starting at index IDX in
6324STRING. OBJ may be either a character or a (smaller) string.
6325This function really does alter the contents of STRING.
6326Since it is impossible to change the length of an existing string,
6327it is an error if OBJ doesn't fit within STRING's actual length.
6328
6329*** char-width returns the width (in columns) of the character CHAR,
6330if it were displayed in the current buffer and the selected window.
6331
6332*** string-width returns the width (in columns) of the text in STRING,
6333if it were displayed in the current buffer and the selected window.
6334
6335*** truncate-string-to-width shortens a string, if necessary,
6336to fit within a certain number of columns. (Of course, it does
6337not alter the string that you give it; it returns a new string
6338which contains all or just part of the existing string.)
6339
6340(truncate-string-to-width STR END-COLUMN &optional START-COLUMN PADDING)
6341
6342This returns the part of STR up to column END-COLUMN.
6343
6344The optional argument START-COLUMN specifies the starting column.
6345If this is non-nil, then the first START-COLUMN columns of the string
6346are not included in the resulting value.
6347
6348The optional argument PADDING, if non-nil, is a padding character to be added
6349at the beginning and end the resulting string, to extend it to exactly
6350WIDTH columns. If PADDING is nil, that means do not pad; then, if STRING
6351is narrower than WIDTH, the value is equal to STRING.
6352
6353If PADDING and START-COLUMN are both non-nil, and if there is no clean
6354place in STRING that corresponds to START-COLUMN (because one
6355character extends across that column), then the padding character
6356PADDING is added one or more times at the beginning of the result
6357string, so that its columns line up as if it really did start at
6358column START-COLUMN.
6359
6360*** When the functions in the list after-change-functions are called,
6361the third argument is the number of bytes in the pre-change text, not
6362necessarily the number of characters. It is, in effect, the
6363difference in buffer position between the beginning and the end of the
6364changed text, before the change.
6365
6366*** The characters Emacs uses are classified in various character
6367sets, each of which has a name which is a symbol. In general there is
6368one character set for each script, not for each language.
6369
6370**** The function charsetp tests whether an object is a character set name.
6371
6372**** The variable charset-list holds a list of character set names.
6373
6374**** char-charset, given a character code, returns the name of the character
6375set that the character belongs to. (The value is a symbol.)
6376
6377**** split-char, given a character code, returns a list containing the
6378name of the character set, followed by one or two byte-values
6379which identify the character within that character set.
6380
6381**** make-char, given a character set name and one or two subsequent
6382byte-values, constructs a character code. This is roughly the
6383opposite of split-char.
6384
6385**** find-charset-region returns a list of the character sets
6386of all the characters between BEG and END.
6387
6388**** find-charset-string returns a list of the character sets
6389of all the characters in a string.
6390
6391*** Here are the Lisp facilities for working with coding systems
6392and specifying coding systems.
6393
6394**** The function coding-system-list returns a list of all coding
6395system names (symbols). With optional argument t, it returns a list
6396of all distinct base coding systems, not including variants.
6397(Variant coding systems are those like latin-1-dos, latin-1-unix
6398and latin-1-mac which specify the end-of-line conversion as well
6399as what to do about code conversion.)
6400
6401**** coding-system-p tests a symbol to see if it is a coding system
6402name. It returns t if so, nil if not.
6403
6404**** file-coding-system-alist specifies which coding systems to use
6405for certain file names. It works like network-coding-system-alist,
6406except that the PATTERN is matched against the file name.
6407
6408Each element has the format (PATTERN . VAL), where PATTERN determines
6409which file names the element applies to. PATTERN should be a regexp
6410to match against a file name.
6411
6412VAL is a coding system, a cons cell containing two coding systems, or
6413a function symbol. If VAL is a coding system, it is used for both
6414decoding what received from the network stream and encoding what sent
6415to the network stream. If VAL is a cons cell containing two coding
6416systems, the car specifies the coding system for decoding, and the cdr
6417specifies the coding system for encoding.
6418
6419If VAL is a function symbol, the function must return a coding system
6420or a cons cell containing two coding systems, which is used as above.
6421
6422**** The variable network-coding-system-alist specifies
6423the coding system to use for network sockets.
6424
6425Each element has the format (PATTERN . VAL), where PATTERN determines
6426which network sockets the element applies to. PATTERN should be
6427either a port number or a regular expression matching some network
6428service names.
6429
6430VAL is a coding system, a cons cell containing two coding systems, or
6431a function symbol. If VAL is a coding system, it is used for both
6432decoding what received from the network stream and encoding what sent
6433to the network stream. If VAL is a cons cell containing two coding
6434systems, the car specifies the coding system for decoding, and the cdr
6435specifies the coding system for encoding.
6436
6437If VAL is a function symbol, the function must return a coding system
6438or a cons cell containing two coding systems, which is used as above.
6439
6440**** process-coding-system-alist specifies which coding systems to use
6441for certain subprocess. It works like network-coding-system-alist,
6442except that the PATTERN is matched against the program name used to
6443start the subprocess.
6444
6445**** The variable default-process-coding-system specifies the coding
6446systems to use for subprocess (and net connection) input and output,
6447when nothing else specifies what to do. The value is a cons cell
6448(OUTPUT-CODING . INPUT-CODING). OUTPUT-CODING applies to output
6449to the subprocess, and INPUT-CODING applies to input from it.
6450
6451**** The variable coding-system-for-write, if non-nil, specifies the
6452coding system to use for writing a file, or for output to a synchronous
6453subprocess.
6454
6455It also applies to any asynchronous subprocess or network connection,
6456but in a different way: the value of coding-system-for-write when you
6457start the subprocess or connection affects that subprocess or
6458connection permanently or until overridden.
6459
6460The variable coding-system-for-write takes precedence over
6461file-coding-system-alist, process-coding-system-alist and
6462network-coding-system-alist, and all other methods of specifying a
6463coding system for output. But most of the time this variable is nil.
6464It exists so that Lisp programs can bind it to a specific coding
6465system for one operation at a time.
6466
6467**** coding-system-for-read applies similarly to input from
6468files, subprocesses or network connections.
6469
6470**** The function process-coding-system tells you what
6471coding systems(s) an existing subprocess is using.
6472The value is a cons cell,
6473 (DECODING-CODING-SYSTEM . ENCODING-CODING-SYSTEM)
6474where DECODING-CODING-SYSTEM is used for decoding output from
6475the subprocess, and ENCODING-CODING-SYSTEM is used for encoding
6476input to the subprocess.
6477
6478**** The function set-process-coding-system can be used to
6479change the coding systems in use for an existing subprocess.
6480
6481** Emacs has a new facility to help users manage the many
6482customization options. To make a Lisp program work with this facility,
6483you need to use the new macros defgroup and defcustom.
6484
6485You use defcustom instead of defvar, for defining a user option
6486variable. The difference is that you specify two additional pieces of
6487information (usually): the "type" which says what values are
6488legitimate, and the "group" which specifies the hierarchy for
6489customization.
6490
6491Thus, instead of writing
6492
6493 (defvar foo-blurgoze nil
6494 "*Non-nil means that foo will act very blurgozely.")
6495
6496you would now write this:
6497
6498 (defcustom foo-blurgoze nil
6499 "*Non-nil means that foo will act very blurgozely."
6500 :type 'boolean
6501 :group foo)
6502
6503The type `boolean' means that this variable has only
6504two meaningful states: nil and non-nil. Other type values
6505describe other possibilities; see the manual for Custom
6506for a description of them.
6507
6508The "group" argument is used to specify a group which the option
6509should belong to. You define a new group like this:
6510
6511 (defgroup ispell nil
6512 "Spell checking using Ispell."
6513 :group 'processes)
6514
6515The "group" argument in defgroup specifies the parent group. The root
6516group is called `emacs'; it should not contain any variables itself,
6517but only other groups. The immediate subgroups of `emacs' correspond
6518to the keywords used by C-h p. Under these subgroups come
6519second-level subgroups that belong to individual packages.
6520
6521Each Emacs package should have its own set of groups. A simple
6522package should have just one group; a more complex package should
6523have a hierarchy of its own groups. The sole or root group of a
6524package should be a subgroup of one or more of the "keyword"
6525first-level subgroups.
6526
6527** New `widget' library for inserting UI components in buffers.
6528
6529This library, used by the new custom library, is documented in a
6530separate manual that accompanies Emacs.
6531
6532** easy-mmode
6533
6534The easy-mmode package provides macros and functions that make
6535developing minor modes easier. Roughly, the programmer has to code
6536only the functionality of the minor mode. All the rest--toggles,
6537predicate, and documentation--can be done in one call to the macro
6538`easy-mmode-define-minor-mode' (see the documentation). See also
6539`easy-mmode-define-keymap'.
6540
6541** Text property changes
6542
6543*** The `intangible' property now works on overlays as well as on a
6544text property.
6545
6546*** The new functions next-char-property-change and
6547previous-char-property-change scan through the buffer looking for a
6548place where either a text property or an overlay might change. The
6549functions take two arguments, POSITION and LIMIT. POSITION is the
6550starting position for the scan. LIMIT says where to stop the scan.
6551
6552If no property change is found before LIMIT, the value is LIMIT. If
6553LIMIT is nil, scan goes to the beginning or end of the accessible part
6554of the buffer. If no property change is found, the value is the
6555position of the beginning or end of the buffer.
6556
6557*** In the `local-map' text property or overlay property, the property
6558value can now be a symbol whose function definition is a keymap. This
6559is an alternative to using the keymap itself.
6560
6561** Changes in invisibility features
6562
6563*** Isearch can now temporarily show parts of the buffer which are
6564hidden by an overlay with a invisible property, when the search match
6565is inside that portion of the buffer. To enable this the overlay
6566should have a isearch-open-invisible property which is a function that
6567would be called having the overlay as an argument, the function should
6568make the overlay visible.
6569
6570During incremental search the overlays are shown by modifying the
6571invisible and intangible properties, if beside this more actions are
6572needed the overlay should have a isearch-open-invisible-temporary
6573which is a function. The function is called with 2 arguments: one is
6574the overlay and the second is nil when it should show the overlay and
6575t when it should hide it.
6576
6577*** add-to-invisibility-spec, remove-from-invisibility-spec
6578
6579Modes that use overlays to hide portions of a buffer should set the
79214ddf
FP
6580invisible property of the overlay to the mode's name (or another symbol)
6581and modify the `buffer-invisibility-spec' to include that symbol.
a933dad1 6582Use `add-to-invisibility-spec' and `remove-from-invisibility-spec' to
79214ddf 6583manipulate the `buffer-invisibility-spec'.
a933dad1
DL
6584Here is an example of how to do this:
6585
6586 ;; If we want to display an ellipsis:
79214ddf 6587 (add-to-invisibility-spec '(my-symbol . t))
a933dad1 6588 ;; If you don't want ellipsis:
79214ddf 6589 (add-to-invisibility-spec 'my-symbol)
a933dad1
DL
6590
6591 ...
6592 (overlay-put (make-overlay beginning end) 'invisible 'my-symbol)
6593
6594 ...
6595 ;; When done with the overlays:
6596 (remove-from-invisibility-spec '(my-symbol . t))
6597 ;; Or respectively:
6598 (remove-from-invisibility-spec 'my-symbol)
6599
6600** Changes in syntax parsing.
6601
6602*** The syntax-directed buffer-scan functions (such as
6603`parse-partial-sexp', `forward-word' and similar functions) can now
6604obey syntax information specified by text properties, if the variable
6605`parse-sexp-lookup-properties' is non-nil.
6606
6607If the value of `parse-sexp-lookup-properties' is nil, the behavior
6608is as before: the syntax-table of the current buffer is always
6609used to determine the syntax of the character at the position.
6610
6611When `parse-sexp-lookup-properties' is non-nil, the syntax of a
6612character in the buffer is calculated thus:
6613
6614 a) if the `syntax-table' text-property of that character
6615 is a cons, this cons becomes the syntax-type;
6616
6617 Valid values of `syntax-table' text-property are: nil, a valid
6618 syntax-table, and a valid syntax-table element, i.e.,
6619 a cons cell of the form (SYNTAX-CODE . MATCHING-CHAR).
6620
6621 b) if the character's `syntax-table' text-property
6622 is a syntax table, this syntax table is used
6623 (instead of the syntax-table of the current buffer) to
6624 determine the syntax type of the character.
6625
6626 c) otherwise the syntax-type is determined by the syntax-table
6627 of the current buffer.
6628
6629*** The meaning of \s in regular expressions is also affected by the
6630value of `parse-sexp-lookup-properties'. The details are the same as
6631for the syntax-directed buffer-scan functions.
6632
6633*** There are two new syntax-codes, `!' and `|' (numeric values 14
6634and 15). A character with a code `!' starts a comment which is ended
6635only by another character with the same code (unless quoted). A
6636character with a code `|' starts a string which is ended only by
6637another character with the same code (unless quoted).
6638
6639These codes are mainly meant for use as values of the `syntax-table'
6640text property.
6641
6642*** The function `parse-partial-sexp' has new semantics for the sixth
6643arg COMMENTSTOP. If it is `syntax-table', parse stops after the start
6644of a comment or a string, or after end of a comment or a string.
6645
6646*** The state-list which the return value from `parse-partial-sexp'
6647(and can also be used as an argument) now has an optional ninth
6648element: the character address of the start of last comment or string;
6649nil if none. The fourth and eighth elements have special values if the
6650string/comment is started by a "!" or "|" syntax-code.
6651
6652*** Since new features of `parse-partial-sexp' allow a complete
6653syntactic parsing, `font-lock' no longer supports
6654`font-lock-comment-start-regexp'.
6655
6656** Changes in face features
6657
6658*** The face functions are now unconditionally defined in Emacs, even
6659if it does not support displaying on a device that supports faces.
6660
6661*** The function face-documentation returns the documentation string
6662of a face (or nil if it doesn't have one).
6663
6664*** The function face-bold-p returns t if a face should be bold.
6665set-face-bold-p sets that flag.
6666
6667*** The function face-italic-p returns t if a face should be italic.
6668set-face-italic-p sets that flag.
6669
6670*** You can now specify foreground and background colors for text
6671by adding elements of the form (foreground-color . COLOR-NAME)
6672and (background-color . COLOR-NAME) to the list of faces in
6673the `face' property (either the character's text property or an
6674overlay property).
6675
6676This means that you no longer need to create named faces to use
6677arbitrary colors in a Lisp package.
6678
6679** Changes in file-handling functions
6680
6681*** File-access primitive functions no longer discard an extra redundant
6682directory name from the beginning of the file name. In other words,
6683they no longer do anything special with // or /~. That conversion
6684is now done only in substitute-in-file-name.
6685
6686This makes it possible for a Lisp program to open a file whose name
6687begins with ~.
6688
6689*** If copy-file is unable to set the date of the output file,
6690it now signals an error with the condition file-date-error.
6691
6692*** The inode number returned by file-attributes may be an integer (if
6693the number fits in a Lisp integer) or a list of integers.
6694
6695*** insert-file-contents can now read from a special file,
6696as long as the arguments VISIT and REPLACE are nil.
6697
6698*** The RAWFILE arg to find-file-noselect, if non-nil, now suppresses
6699character code conversion as well as other things.
6700
6701Meanwhile, this feature does work with remote file names
6702(formerly it did not).
6703
6704*** Lisp packages which create temporary files should use the TMPDIR
6705environment variable to decide which directory to put them in.
6706
6707*** interpreter-mode-alist elements now specify regexps
6708instead of constant strings.
6709
6710*** expand-file-name no longer treats `//' or `/~' specially. It used
6711to delete all the text of a file name up through the first slash of
6712any `//' or `/~' sequence. Now it passes them straight through.
6713
6714substitute-in-file-name continues to treat those sequences specially,
6715in the same way as before.
6716
6717*** The variable `format-alist' is more general now.
6718The FROM-FN and TO-FN in a format definition can now be strings
6719which specify shell commands to use as filters to perform conversion.
6720
6721*** The new function access-file tries to open a file, and signals an
6722error if that fails. If the open succeeds, access-file does nothing
6723else, and returns nil.
6724
6725*** The function insert-directory now signals an error if the specified
6726directory cannot be listed.
6727
6728** Changes in minibuffer input
6729
6730*** The functions read-buffer, read-variable, read-command, read-string
6731read-file-name, read-from-minibuffer and completing-read now take an
6732additional argument which specifies the default value. If this
6733argument is non-nil, it should be a string; that string is used in two
6734ways:
6735
6736 It is returned if the user enters empty input.
6737 It is available through the history command M-n.
6738
6739*** The functions read-string, read-from-minibuffer,
6740read-no-blanks-input and completing-read now take an additional
6741argument INHERIT-INPUT-METHOD. If this is non-nil, then the
6742minibuffer inherits the current input method and the setting of
6743enable-multibyte-characters from the previously current buffer.
6744
6745In an interactive spec, you can use M instead of s to read an
6746argument in this way.
6747
6748*** All minibuffer input functions discard text properties
6749from the text you enter in the minibuffer, unless the variable
6750minibuffer-allow-text-properties is non-nil.
6751
6752** Echo area features
6753
6754*** Clearing the echo area now runs the normal hook
6755echo-area-clear-hook. Note that the echo area can be used while the
6756minibuffer is active; in that case, the minibuffer is still active
6757after the echo area is cleared.
6758
6759*** The function current-message returns the message currently displayed
6760in the echo area, or nil if there is none.
6761
6762** Keyboard input features
6763
6764*** tty-erase-char is a new variable that reports which character was
6765set up as the terminal's erase character when time Emacs was started.
6766
6767*** num-nonmacro-input-events is the total number of input events
6768received so far from the terminal. It does not count those generated
6769by keyboard macros.
6770
6771** Frame-related changes
6772
6773*** make-frame runs the normal hook before-make-frame-hook just before
6774creating a frame, and just after creating a frame it runs the abnormal
6775hook after-make-frame-functions with the new frame as arg.
6776
6777*** The new hook window-configuration-change-hook is now run every time
6778the window configuration has changed. The frame whose configuration
6779has changed is the selected frame when the hook is run.
6780
6781*** Each frame now independently records the order for recently
6782selected buffers, in its buffer-list frame parameter, so that the
6783value of other-buffer is now based on the buffers recently displayed
6784in the selected frame.
6785
6786*** The value of the frame parameter vertical-scroll-bars
6787is now `left', `right' or nil. A non-nil value specifies
6788which side of the window to put the scroll bars on.
6789
6790** X Windows features
6791
6792*** You can examine X resources for other applications by binding
6793x-resource-class around a call to x-get-resource. The usual value of
6794x-resource-class is "Emacs", which is the correct value for Emacs.
6795
6796*** In menus, checkboxes and radio buttons now actually work.
6797The menu displays the current status of the box or button.
6798
6799*** The function x-list-fonts now takes an optional fourth argument
6800MAXIMUM which sets a limit on how many matching fonts to return.
6801A smaller value of MAXIMUM makes the function faster.
6802
6803If the only question is whether *any* font matches the pattern,
6804it is good to supply 1 for this argument.
6805
6806** Subprocess features
6807
6808*** A reminder: it is no longer necessary for subprocess filter
6809functions and sentinels to do save-match-data, because Emacs does this
6810automatically.
6811
6812*** The new function shell-command-to-string executes a shell command
6813and returns the output from the command as a string.
6814
6815*** The new function process-contact returns t for a child process,
6816and (HOSTNAME SERVICE) for a net connection.
6817
6818** An error in running pre-command-hook or post-command-hook
6819does clear the variable to nil. The documentation was wrong before.
6820
6821** In define-key-after, if AFTER is t, the new binding now always goes
6822at the end of the keymap. If the keymap is a menu, this means it
6823goes after the other menu items.
6824
6825** If you have a program that makes several changes in the same area
79214ddf 6826of the buffer, you can use the macro combine-after-change-calls
a933dad1
DL
6827around that Lisp code to make it faster when after-change hooks
6828are in use.
6829
6830The macro arranges to call the after-change functions just once for a
6831series of several changes--if that seems safe.
6832
6833Don't alter the variables after-change-functions and
6834after-change-function within the body of a combine-after-change-calls
6835form.
6836
6837** If you define an abbrev (with define-abbrev) whose EXPANSION
6838is not a string, then the abbrev does not expand in the usual sense,
6839but its hook is still run.
6840
6841** Normally, the Lisp debugger is not used (even if you have enabled it)
6842for errors that are handled by condition-case.
6843
6844If you set debug-on-signal to a non-nil value, then the debugger is called
6845regardless of whether there is a handler for the condition. This is
6846useful for debugging problems that happen inside of a condition-case.
6847
6848This mode of operation seems to be unreliable in other ways. Errors that
6849are normal and ought to be handled, perhaps in timers or process
6850filters, will instead invoke the debugger. So don't say you weren't
6851warned.
6852
6853** The new variable ring-bell-function lets you specify your own
6854way for Emacs to "ring the bell".
6855
6856** If run-at-time's TIME argument is t, the action is repeated at
6857integral multiples of REPEAT from the epoch; this is useful for
6858functions like display-time.
6859
6860** You can use the function locate-library to find the precise file
6861name of a Lisp library. This isn't new, but wasn't documented before.
6862
6863** Commands for entering view mode have new optional arguments that
6864can be used from Lisp. Low-level entrance to and exit from view mode
6865is done by functions view-mode-enter and view-mode-exit.
6866
6867** batch-byte-compile-file now makes Emacs return a nonzero status code
6868if there is an error in compilation.
6869
6870** pop-to-buffer, switch-to-buffer-other-window and
6871switch-to-buffer-other-frame now accept an additional optional
6872argument NORECORD, much like switch-to-buffer. If it is non-nil,
6873they don't put the buffer at the front of the buffer list.
6874
6875** If your .emacs file leaves the *scratch* buffer non-empty,
6876Emacs does not display the startup message, so as to avoid changing
6877the *scratch* buffer.
6878
6879** The new function regexp-opt returns an efficient regexp to match a string.
6880The arguments are STRINGS and (optionally) PAREN. This function can be used
6881where regexp matching or searching is intensively used and speed is important,
6882e.g., in Font Lock mode.
6883
6884** The variable buffer-display-count is local to each buffer,
6885and is incremented each time the buffer is displayed in a window.
6886It starts at 0 when the buffer is created.
6887
6888** The new function compose-mail starts composing a mail message
6889using the user's chosen mail composition agent (specified with the
6890variable mail-user-agent). It has variants compose-mail-other-window
6891and compose-mail-other-frame.
6892
6893** The `user-full-name' function now takes an optional parameter which
6894can either be a number (the UID) or a string (the login name). The
6895full name of the specified user will be returned.
6896
6897** Lisp packages that load files of customizations, or any other sort
6898of user profile, should obey the variable init-file-user in deciding
6899where to find it. They should load the profile of the user name found
6900in that variable. If init-file-user is nil, meaning that the -q
6901option was used, then Lisp packages should not load the customization
6902files at all.
6903
6904** format-time-string now allows you to specify the field width
6905and type of padding. This works as in printf: you write the field
6906width as digits in the middle of a %-construct. If you start
6907the field width with 0, it means to pad with zeros.
6908
6909For example, %S normally specifies the number of seconds since the
6910minute; %03S means to pad this with zeros to 3 positions, %_3S to pad
6911with spaces to 3 positions. Plain %3S pads with zeros, because that
6912is how %S normally pads to two positions.
6913
6914** thing-at-point now supports a new kind of "thing": url.
6915
6916** imenu.el changes.
6917
6918You can now specify a function to be run when selecting an
79214ddf 6919item from menu created by imenu.
a933dad1
DL
6920
6921An example of using this feature: if we define imenu items for the
6922#include directives in a C file, we can open the included file when we
6923select one of those items.
6924\f
6925* Emacs 19.34 is a bug-fix release with no user-visible changes.
6926\f
6927* Changes in Emacs 19.33.
6928
6929** Bibtex mode no longer turns on Auto Fill automatically. (No major
6930mode should do that--it is the user's choice.)
6931
6932** The variable normal-auto-fill-function specifies the function to
6933use for auto-fill-function, if and when Auto Fill is turned on.
6934Major modes can set this locally to alter how Auto Fill works.
6935\f
6936* Editing Changes in Emacs 19.32
6937
6938** C-x f with no argument now signals an error.
6939To set the fill column at the current column, use C-u C-x f.
6940
6941** Expanding dynamic abbrevs with M-/ is now smarter about case
6942conversion. If you type the abbreviation with mixed case, and it
6943matches the beginning of the expansion including case, then the
6944expansion is copied verbatim. Using SPC M-/ to copy an additional
6945word always copies it verbatim except when the previous copied word is
6946all caps.
6947
6948** On a non-windowing terminal, which can display only one Emacs frame
6949at a time, creating a new frame with C-x 5 2 also selects that frame.
6950
6951When using a display that can show multiple frames at once, C-x 5 2
6952does make the frame visible, but does not select it. This is the same
6953as in previous Emacs versions.
6954
6955** You can use C-x 5 2 to create multiple frames on MSDOS, just as on a
6956non-X terminal on Unix. Of course, only one frame is visible at any
6957time, since your terminal doesn't have the ability to display multiple
6958frames.
6959
6960** On Windows, set win32-pass-alt-to-system to a non-nil value
6961if you would like tapping the Alt key to invoke the Windows menu.
6962This feature is not enabled by default; since the Alt key is also the
6963Meta key, it is too easy and painful to activate this feature by
6964accident.
6965
6966** The command apply-macro-to-region-lines repeats the last defined
6967keyboard macro once for each complete line within the current region.
6968It does this line by line, by moving point to the beginning of that
6969line and then executing the macro.
6970
6971This command is not new, but was never documented before.
6972
6973** You can now use Mouse-1 to place the region around a string constant
6974(something surrounded by doublequote characters or other delimiter
6975characters of like syntax) by double-clicking on one of the delimiting
6976characters.
6977
6978** Font Lock mode
6979
6980*** Font Lock support modes
6981
6982Font Lock can be configured to use Fast Lock mode and Lazy Lock mode (see
6983below) in a flexible way. Rather than adding the appropriate function to the
6984hook font-lock-mode-hook, you can use the new variable font-lock-support-mode
6985to control which modes have Fast Lock mode or Lazy Lock mode turned on when
6986Font Lock mode is enabled.
6987
6988For example, to use Fast Lock mode when Font Lock mode is turned on, put:
6989
6990 (setq font-lock-support-mode 'fast-lock-mode)
6991
6992in your ~/.emacs.
6993
6994*** lazy-lock
6995
6996The lazy-lock package speeds up Font Lock mode by making fontification occur
6997only when necessary, such as when a previously unfontified part of the buffer
6998becomes visible in a window. When you create a buffer with Font Lock mode and
6999Lazy Lock mode turned on, the buffer is not fontified. When certain events
7000occur (such as scrolling), Lazy Lock makes sure that the visible parts of the
7001buffer are fontified. Lazy Lock also defers on-the-fly fontification until
7002Emacs has been idle for a given amount of time.
7003
7004To use this package, put in your ~/.emacs:
7005
7006 (setq font-lock-support-mode 'lazy-lock-mode)
7007
7008To control the package behaviour, see the documentation for `lazy-lock-mode'.
7009
7010** Changes in BibTeX mode.
7011
7012*** For all entries allow spaces and tabs between opening brace or
7013paren and key.
7014
7015*** Non-escaped double-quoted characters (as in `Sch"of') are now
7016supported.
7017
7018** Gnus changes.
7019
7020Gnus, the Emacs news reader, has undergone further rewriting. Many new
7021commands and variables have been added. There should be no
7022significant incompatibilities between this Gnus version and the
7023previously released version, except in the message composition area.
7024
7025Below is a list of the more user-visible changes. Coding changes
7026between Gnus 5.1 and 5.2 are more extensive.
7027
79214ddf 7028*** A new message composition mode is used. All old customization
a933dad1
DL
7029variables for mail-mode, rnews-reply-mode and gnus-msg are now
7030obsolete.
7031
7032*** Gnus is now able to generate "sparse" threads -- threads where
7033missing articles are represented by empty nodes.
7034
7035 (setq gnus-build-sparse-threads 'some)
7036
7037*** Outgoing articles are stored on a special archive server.
7038
7039 To disable this: (setq gnus-message-archive-group nil)
7040
7041*** Partial thread regeneration now happens when articles are
79214ddf 7042referred.
a933dad1
DL
7043
7044*** Gnus can make use of GroupLens predictions:
7045
7046 (setq gnus-use-grouplens t)
7047
7048*** A trn-line tree buffer can be displayed.
7049
7050 (setq gnus-use-trees t)
7051
7052*** An nn-like pick-and-read minor mode is available for the summary
79214ddf 7053buffers.
a933dad1
DL
7054
7055 (add-hook 'gnus-summary-mode-hook 'gnus-pick-mode)
7056
7057*** In binary groups you can use a special binary minor mode:
7058
7059 `M-x gnus-binary-mode'
7060
7061*** Groups can be grouped in a folding topic hierarchy.
7062
7063 (add-hook 'gnus-group-mode-hook 'gnus-topic-mode)
7064
7065*** Gnus can re-send and bounce mail.
7066
7067 Use the `S D r' and `S D b'.
7068
7069*** Groups can now have a score, and bubbling based on entry frequency
7070is possible.
7071
7072 (add-hook 'gnus-summary-exit-hook 'gnus-summary-bubble-group)
7073
7074*** Groups can be process-marked, and commands can be performed on
7075groups of groups.
7076
7077*** Caching is possible in virtual groups.
7078
7079*** nndoc now understands all kinds of digests, mail boxes, rnews news
79214ddf 7080batches, ClariNet briefs collections, and just about everything else.
a933dad1
DL
7081
7082*** Gnus has a new backend (nnsoup) to create/read SOUP packets.
7083
7084*** The Gnus cache is much faster.
7085
7086*** Groups can be sorted according to many criteria.
7087
7088 For instance: (setq gnus-group-sort-function 'gnus-group-sort-by-rank)
7089
7090*** New group parameters have been introduced to set list-address and
7091expiration times.
7092
7093*** All formatting specs allow specifying faces to be used.
7094
7095*** There are several more commands for setting/removing/acting on
7096process marked articles on the `M P' submap.
7097
7098*** The summary buffer can be limited to show parts of the available
7099articles based on a wide range of criteria. These commands have been
7100bound to keys on the `/' submap.
7101
7102*** Articles can be made persistent -- as an alternative to saving
7103articles with the `*' command.
7104
7105*** All functions for hiding article elements are now toggles.
7106
7107*** Article headers can be buttonized.
7108
7109 (add-hook 'gnus-article-display-hook 'gnus-article-add-buttons-to-head)
7110
7111*** All mail backends support fetching articles by Message-ID.
7112
79214ddf 7113*** Duplicate mail can now be treated properly. See the
a933dad1
DL
7114`nnmail-treat-duplicates' variable.
7115
7116*** All summary mode commands are available directly from the article
79214ddf 7117buffer.
a933dad1
DL
7118
7119*** Frames can be part of `gnus-buffer-configuration'.
7120
7121*** Mail can be re-scanned by a daemonic process.
7122
7123*** Gnus can make use of NoCeM files to filter spam.
7124
7125 (setq gnus-use-nocem t)
7126
79214ddf 7127*** Groups can be made permanently visible.
a933dad1
DL
7128
7129 (setq gnus-permanently-visible-groups "^nnml:")
7130
79214ddf 7131*** Many new hooks have been introduced to make customizing easier.
a933dad1
DL
7132
7133*** Gnus respects the Mail-Copies-To header.
7134
79214ddf 7135*** Threads can be gathered by looking at the References header.
a933dad1 7136
79214ddf 7137 (setq gnus-summary-thread-gathering-function
a933dad1
DL
7138 'gnus-gather-threads-by-references)
7139
7140*** Read articles can be stored in a special backlog buffer to avoid
79214ddf 7141refetching.
a933dad1
DL
7142
7143 (setq gnus-keep-backlog 50)
7144
7145*** A clean copy of the current article is always stored in a separate
7146buffer to allow easier treatment.
7147
7148*** Gnus can suggest where to save articles. See `gnus-split-methods'.
7149
7150*** Gnus doesn't have to do as much prompting when saving.
7151
7152 (setq gnus-prompt-before-saving t)
7153
7154*** gnus-uu can view decoded files asynchronously while fetching
79214ddf 7155articles.
a933dad1
DL
7156
7157 (setq gnus-uu-grabbed-file-functions 'gnus-uu-grab-view)
7158
79214ddf 7159*** Filling in the article buffer now works properly on cited text.
a933dad1
DL
7160
7161*** Hiding cited text adds buttons to toggle hiding, and how much
7162cited text to hide is now customizable.
7163
7164 (setq gnus-cited-lines-visible 2)
7165
7166*** Boring headers can be hidden.
7167
7168 (add-hook 'gnus-article-display-hook 'gnus-article-hide-boring-headers)
7169
7170*** Default scoring values can now be set from the menu bar.
7171
7172*** Further syntax checking of outgoing articles have been added.
7173
7174The Gnus manual has been expanded. It explains all these new features
7175in greater detail.
7176\f
7177* Lisp Changes in Emacs 19.32
7178
7179** The function set-visited-file-name now accepts an optional
7180second argument NO-QUERY. If it is non-nil, then the user is not
7181asked for confirmation in the case where the specified file already
7182exists.
7183
7184** The variable print-length applies to printing vectors and bitvectors,
7185as well as lists.
7186
7187** The new function keymap-parent returns the parent keymap
7188of a given keymap.
7189
7190** The new function set-keymap-parent specifies a new parent for a
7191given keymap. The arguments are KEYMAP and PARENT. PARENT must be a
7192keymap or nil.
7193
7194** Sometimes menu keymaps use a command name, a symbol, which is really
7195an automatically generated alias for some other command, the "real"
7196name. In such a case, you should give that alias symbol a non-nil
7197menu-alias property. That property tells the menu system to look for
7198equivalent keys for the real name instead of equivalent keys for the
7199alias.
7200\f
7201* Editing Changes in Emacs 19.31
7202
7203** Freedom of the press restricted in the United States.
7204
7205Emacs has been censored in accord with the Communications Decency Act.
7206This includes removing some features of the doctor program. That law
7207was described by its supporters as a ban on pornography, but it bans
7208far more than that. The Emacs distribution has never contained any
7209pornography, but parts of it were nonetheless prohibited.
7210
7211For information on US government censorship of the Internet, and what
7212you can do to bring back freedom of the press, see the web site
7213`http://www.vtw.org/'.
7214
7215** A note about C mode indentation customization.
7216
7217The old (Emacs 19.29) ways of specifying a C indentation style
7218do not normally work in the new implementation of C mode.
7219It has its own methods of customizing indentation, which are
7220much more powerful than the old C mode. See the Editing Programs
7221chapter of the manual for details.
7222
7223However, you can load the library cc-compat to make the old
7224customization variables take effect.
7225
7226** Marking with the mouse.
7227
7228When you mark a region with the mouse, the region now remains
7229highlighted until the next input event, regardless of whether you are
7230using M-x transient-mark-mode.
7231
7232** Improved Windows NT/95 support.
7233
7234*** Emacs now supports scroll bars on Windows NT and Windows 95.
7235
7236*** Emacs now supports subprocesses on Windows 95. (Subprocesses used
7237to work on NT only and not on 95.)
7238
7239*** There are difficulties with subprocesses, though, due to problems
7240in Windows, beyond the control of Emacs. They work fine as long as
7241you run Windows applications. The problems arise when you run a DOS
7242application in a subprocesses. Since current shells run as DOS
7243applications, these problems are significant.
7244
7245If you run a DOS application in a subprocess, then the application is
7246likely to busy-wait, which means that your machine will be 100% busy.
7247However, if you don't mind the temporary heavy load, the subprocess
7248will work OK as long as you tell it to terminate before you start any
7249other DOS application as a subprocess.
7250
7251Emacs is unable to terminate or interrupt a DOS subprocess.
7252You have to do this by providing input directly to the subprocess.
7253
7254If you run two DOS applications at the same time in two separate
7255subprocesses, even if one of them is asynchronous, you will probably
7256have to reboot your machine--until then, it will remain 100% busy.
7257Windows simply does not cope when one Windows process tries to run two
7258separate DOS subprocesses. Typing CTL-ALT-DEL and then choosing
7259Shutdown seems to work although it may take a few minutes.
7260
7261** M-x resize-minibuffer-mode.
7262
7263This command, not previously mentioned in NEWS, toggles a mode in
7264which the minibuffer window expands to show as many lines as the
7265minibuffer contains.
7266
7267** `title' frame parameter and resource.
7268
7269The `title' X resource now specifies just the frame title, nothing else.
7270It does not affect the name used for looking up other X resources.
7271It works by setting the new `title' frame parameter, which likewise
7272affects just the displayed title of the frame.
7273
7274The `name' parameter continues to do what it used to do:
7275it specifies the frame name for looking up X resources,
7276and also serves as the default for the displayed title
7277when the `title' parameter is unspecified or nil.
7278
7279** Emacs now uses the X toolkit by default, if you have a new
7280enough version of X installed (X11R5 or newer).
7281
7282** When you compile Emacs with the Motif widget set, Motif handles the
7283F10 key by activating the menu bar. To avoid confusion, the usual
7284Emacs binding of F10 is replaced with a no-op when using Motif.
7285
7286If you want to be able to use F10 in Emacs, you can rebind the Motif
7287menubar to some other key which you don't use. To do so, add
7288something like this to your X resources file. This example rebinds
7289the Motif menu bar activation key to S-F12:
7290
7291 Emacs*defaultVirtualBindings: osfMenuBar : Shift<Key>F12
7292
7293** In overwrite mode, DEL now inserts spaces in most cases
7294to replace the characters it "deletes".
7295
7296** The Rmail summary now shows the number of lines in each message.
7297
7298** Rmail has a new command M-x unforward-rmail-message, which extracts
7299a forwarded message from the message that forwarded it. To use it,
7300select a message which contains a forwarded message and then type the command.
7301It inserts the forwarded message as a separate Rmail message
7302immediately after the selected one.
7303
7304This command also undoes the textual modifications that are standardly
7305made, as part of forwarding, by Rmail and other mail reader programs.
7306
7307** Turning off saving of .saves-... files in your home directory.
7308
7309Each Emacs session writes a file named .saves-... in your home
7310directory to record which files M-x recover-session should recover.
7311If you exit Emacs normally with C-x C-c, it deletes that file. If
7312Emacs or the operating system crashes, the file remains for M-x
7313recover-session.
7314
7315You can turn off the writing of these files by setting
7316auto-save-list-file-name to nil. If you do this, M-x recover-session
7317will not work.
7318
7319Some previous Emacs versions failed to delete these files even on
7320normal exit. This is fixed now. If you are thinking of turning off
7321this feature because of past experiences with versions that had this
7322bug, it would make sense to check whether you still want to do so
7323now that the bug is fixed.
7324
7325** Changes to Version Control (VC)
7326
7327There is a new variable, vc-follow-symlinks. It indicates what to do
7328when you visit a link to a file that is under version control.
7329Editing the file through the link bypasses the version control system,
7330which is dangerous and probably not what you want.
7331
7332If this variable is t, VC follows the link and visits the real file,
7333telling you about it in the echo area. If it is `ask' (the default),
7334VC asks for confirmation whether it should follow the link. If nil,
7335the link is visited and a warning displayed.
7336
7337** iso-acc.el now lets you specify a choice of language.
7338Languages include "latin-1" (the default) and "latin-2" (which
7339is designed for entering ISO Latin-2 characters).
7340
7341There are also choices for specific human languages such as French and
7342Portuguese. These are subsets of Latin-1, which differ in that they
7343enable only the accent characters needed for particular language.
7344The other accent characters, not needed for the chosen language,
7345remain normal.
7346
7347** Posting articles and sending mail now has M-TAB completion on various
7348header fields (Newsgroups, To, CC, ...).
7349
7350Completion in the Newsgroups header depends on the list of groups
7351known to your news reader. Completion in the Followup-To header
7352offers those groups which are in the Newsgroups header, since
7353Followup-To usually just holds one of those.
7354
7355Completion in fields that hold mail addresses works based on the list
7356of local users plus your aliases. Additionally, if your site provides
7357a mail directory or a specific host to use for any unrecognized user
7358name, you can arrange to query that host for completion also. (See the
7359documentation of variables `mail-directory-process' and
7360`mail-directory-stream'.)
7361
7362** A greatly extended sgml-mode offers new features such as (to be configured)
7363skeletons with completing read for tags and attributes, typing named
7364characters including optionally all 8bit characters, making tags invisible
7365with optional alternate display text, skipping and deleting tag(pair)s.
7366
7367Note: since Emacs' syntax feature cannot limit the special meaning of ', " and
7368- to inside <>, for some texts the result, especially of font locking, may be
7369wrong (see `sgml-specials' if you get wrong results).
7370
7371The derived html-mode configures this with tags and attributes more or
7372less HTML3ish. It also offers optional quick keys like C-c 1 for
7373headline or C-c u for unordered list (see `html-quick-keys'). Edit /
7374Text Properties / Face or M-g combinations create tags as applicable.
7375Outline minor mode is supported and level 1 font-locking tries to
7376fontify tag contents (which only works when they fit on one line, due
7377to a limitation in font-lock).
7378
7379External viewing via browse-url can occur automatically upon saving.
7380
7381** M-x imenu-add-to-menubar now adds to the menu bar for the current
7382buffer only. If you want to put an Imenu item in the menu bar for all
7383buffers that use a particular major mode, use the mode hook, as in
7384this example:
7385
7386 (add-hook 'emacs-lisp-mode-hook
7387 '(lambda () (imenu-add-to-menubar "Index")))
7388
7389** Changes in BibTeX mode.
7390
7391*** Field names may now contain digits, hyphens, and underscores.
7392
7393*** Font Lock mode is now supported.
7394
7395*** bibtex-make-optional-field is no longer interactive.
7396
7397*** If bibtex-maintain-sorted-entries is non-nil, inserting new
7398entries is now done with a faster algorithm. However, inserting
7399will fail in this case if the buffer contains invalid entries or
7400isn't in sorted order, so you should finish each entry with C-c C-c
7401(bibtex-close-entry) after you have inserted or modified it.
7402The default value of bibtex-maintain-sorted-entries is nil.
7403
7404*** Function `show-all' is no longer bound to a key, since C-u C-c C-q
7405does the same job.
7406
7407*** Entries with quotes inside quote-delimited fields (as `author =
7408"Stefan Sch{\"o}f"') are now supported.
7409
7410*** Case in field names doesn't matter anymore when searching for help
7411text.
7412
7413** Font Lock mode
7414
7415*** Global Font Lock mode
7416
7417Font Lock mode can be turned on globally, in buffers that support it, by the
7418new command global-font-lock-mode. You can use the new variable
7419font-lock-global-modes to control which modes have Font Lock mode automagically
7420turned on. By default, this variable is set so that Font Lock mode is turned
7421on globally where the buffer mode supports it.
7422
7423For example, to automagically turn on Font Lock mode where supported, put:
7424
7425 (global-font-lock-mode t)
7426
7427in your ~/.emacs.
7428
7429*** Local Refontification
7430
7431In Font Lock mode, editing a line automatically refontifies that line only.
7432However, if your change alters the syntactic context for following lines,
7433those lines remain incorrectly fontified. To refontify them, use the new
7434command M-g M-g (font-lock-fontify-block).
7435
7436In certain major modes, M-g M-g refontifies the entire current function.
7437(The variable font-lock-mark-block-function controls how to find the
7438current function.) In other major modes, M-g M-g refontifies 16 lines
7439above and below point.
7440
7441With a prefix argument N, M-g M-g refontifies N lines above and below point.
7442
7443** Follow mode
7444
7445Follow mode is a new minor mode combining windows showing the same
7446buffer into one tall "virtual window". The windows are typically two
7447side-by-side windows. Follow mode makes them scroll together as if
7448they were a unit. To use it, go to a frame with just one window,
7449split it into two side-by-side windows using C-x 3, and then type M-x
7450follow-mode.
7451
7452M-x follow-mode turns off Follow mode if it is already enabled.
7453
7454To display two side-by-side windows and activate Follow mode, use the
7455command M-x follow-delete-other-windows-and-split.
7456
7457** hide-show changes.
7458
7459The hooks hs-hide-hooks and hs-show-hooks have been renamed
7460to hs-hide-hook and hs-show-hook, to follow the convention for
7461normal hooks.
7462
7463** Simula mode now has a menu containing the most important commands.
7464The new command simula-indent-exp is bound to C-M-q.
7465
7466** etags can now handle programs written in Erlang. Files are
7467recognised by the extensions .erl and .hrl. The tagged lines are
7468those that begin a function, record, or macro.
7469
7470** MSDOS Changes
7471
7472*** It is now possible to compile Emacs with the version 2 of DJGPP.
7473Compilation with DJGPP version 1 also still works.
7474
7475*** The documentation of DOS-specific aspects of Emacs was rewritten
7476and expanded; see the ``MS-DOS'' node in the on-line docs.
7477
7478*** Emacs now uses ~ for backup file names, not .bak.
7479
7480*** You can simulate mouse-3 on two-button mice by simultaneously
7481pressing both mouse buttons.
7482
7483*** A number of packages and commands which previously failed or had
7484restricted functionality on MS-DOS, now work. The most important ones
79214ddf 7485are:
a933dad1
DL
7486
7487**** Printing (both with `M-x lpr-buffer' and with `ps-print' package)
7488now works.
7489
7490**** `Ediff' works (in a single-frame mode).
7491
7492**** `M-x display-time' can be used on MS-DOS (due to the new
7493implementation of Emacs timers, see below).
7494
7495**** `Dired' supports Unix-style shell wildcards.
7496
7497**** The `c-macro-expand' command now works as on other platforms.
7498
7499**** `M-x recover-session' works.
7500
7501**** `M-x list-colors-display' displays all the available colors.
7502
7503**** The `TPU-EDT' package works.
7504\f
7505* Lisp changes in Emacs 19.31.
7506
7507** The function using-unix-filesystems on Windows NT and Windows 95
7508tells Emacs to read and write files assuming that they reside on a
7509remote Unix filesystem. No CR/LF translation is done on any files in
7510this case. Invoking using-unix-filesystems with t activates this
7511behavior, and invoking it with any other value deactivates it.
7512
7513** Change in system-type and system-configuration values.
7514
7515The value of system-type on a Linux-based GNU system is now `lignux',
7516not `linux'. This means that some programs which use `system-type'
7517need to be changed. The value of `system-configuration' will also
7518be different.
7519
7520It is generally recommended to use `system-configuration' rather
7521than `system-type'.
7522
7523See the file LINUX-GNU in this directory for more about this.
7524
7525** The functions shell-command and dired-call-process
7526now run file name handlers for default-directory, if it has them.
7527
7528** Undoing the deletion of text now restores the positions of markers
7529that pointed into or next to the deleted text.
7530
7531** Timers created with run-at-time now work internally to Emacs, and
7532no longer use a separate process. Therefore, they now work more
7533reliably and can be used for shorter time delays.
7534
7535The new function run-with-timer is a convenient way to set up a timer
7536to run a specified amount of time after the present. A call looks
7537like this:
7538
7539 (run-with-timer SECS REPEAT FUNCTION ARGS...)
7540
7541SECS says how many seconds should elapse before the timer happens.
7542It may be an integer or a floating point number. When the timer
7543becomes ripe, the action is to call FUNCTION with arguments ARGS.
7544
7545REPEAT gives the interval for repeating the timer (measured in
7546seconds). It may be an integer or a floating point number. nil or 0
7547means don't repeat at all--call FUNCTION just once.
7548
7549*** with-timeout provides an easy way to do something but give
7550up if too much time passes.
7551
7552 (with-timeout (SECONDS TIMEOUT-FORMS...) BODY...)
7553
7554This executes BODY, but gives up after SECONDS seconds.
7555If it gives up, it runs the TIMEOUT-FORMS and returns the value
7556of the last one of them. Normally it returns the value of the last
7557form in BODY.
7558
7559*** You can now arrange to call a function whenever Emacs is idle for
7560a certain length of time. To do this, call run-with-idle-timer. A
7561call looks like this:
7562
7563 (run-with-idle-timer SECS REPEAT FUNCTION ARGS...)
7564
7565SECS says how many seconds of idleness should elapse before the timer
7566runs. It may be an integer or a floating point number. When the
7567timer becomes ripe, the action is to call FUNCTION with arguments
7568ARGS.
7569
7570Emacs becomes idle whenever it finishes executing a keyboard or mouse
7571command. It remains idle until it receives another keyboard or mouse
7572command.
7573
7574REPEAT, if non-nil, means this timer should be activated again each
7575time Emacs becomes idle and remains idle for SECS seconds The timer
7576does not repeat if Emacs *remains* idle; it runs at most once after
7577each time Emacs becomes idle.
7578
7579If REPEAT is nil, the timer runs just once, the first time Emacs is
7580idle for SECS seconds.
7581
7582*** post-command-idle-hook is now obsolete; you shouldn't use it at
7583all, because it interferes with the idle timer mechanism. If your
7584programs use post-command-idle-hook, convert them to use idle timers
7585instead.
7586
7587*** y-or-n-p-with-timeout lets you ask a question but give up if
7588there is no answer within a certain time.
7589
7590 (y-or-n-p-with-timeout PROMPT SECONDS DEFAULT-VALUE)
7591
7592asks the question PROMPT (just like y-or-n-p). If the user answers
7593within SECONDS seconds, it returns the answer that the user gave.
7594Otherwise it gives up after SECONDS seconds, and returns DEFAULT-VALUE.
7595
7596** Minor change to `encode-time': you can now pass more than seven
7597arguments. If you do that, the first six arguments have the usual
7598meaning, the last argument is interpreted as the time zone, and the
7599arguments in between are ignored.
7600
7601This means that it works to use the list returned by `decode-time' as
7602the list of arguments for `encode-time'.
7603
7604** The default value of load-path now includes the directory
7605/usr/local/share/emacs/VERSION/site-lisp In addition to
7606/usr/local/share/emacs/site-lisp. You can use this new directory for
7607site-specific Lisp packages that belong with a particular Emacs
7608version.
7609
7610It is not unusual for a Lisp package that works well in one Emacs
7611version to cause trouble in another. Sometimes packages need updating
7612for incompatible changes; sometimes they look at internal data that
7613has changed; sometimes the package has been installed in Emacs itself
7614and the installed version should be used. Whatever the reason for the
7615problem, this new feature makes it easier to solve.
7616
7617** When your program contains a fixed file name (like .completions or
7618.abbrev.defs), the file name usually needs to be different on operating
7619systems with limited file name syntax.
7620
7621Now you can avoid ad-hoc conditionals by using the function
7622convert-standard-filename to convert the file name to a proper form
7623for each operating system. Here is an example of use, from the file
7624completions.el:
7625
7626(defvar save-completions-file-name
7627 (convert-standard-filename "~/.completions")
7628 "*The filename to save completions to.")
7629
7630This sets the variable save-completions-file-name to a value that
7631depends on the operating system, because the definition of
7632convert-standard-filename depends on the operating system. On
7633Unix-like systems, it returns the specified file name unchanged. On
7634MS-DOS, it adapts the name to fit the limitations of that system.
7635
7636** The interactive spec N now returns the numeric prefix argument
7637rather than the raw prefix argument. (It still reads a number using the
7638minibuffer if there is no prefix argument at all.)
7639
7640** When a process is deleted, this no longer disconnects the process
7641marker from its buffer position.
7642
7643** The variable garbage-collection-messages now controls whether
7644Emacs displays a message at the beginning and end of garbage collection.
7645The default is nil, meaning there are no messages.
7646
7647** The variable debug-ignored-errors specifies certain kinds of errors
7648that should not enter the debugger. Its value is a list of error
7649condition symbols and/or regular expressions. If the error has any
7650of the condition symbols listed, or if any of the regular expressions
7651matches the error message, then that error does not enter the debugger,
7652regardless of the value of debug-on-error.
7653
7654This variable is initialized to match certain common but uninteresting
7655errors that happen often during editing.
7656
7657** The new function error-message-string converts an error datum
7658into its error message. The error datum is what condition-case
7659puts into the variable, to describe the error that happened.
7660
7661** Anything that changes which buffer appears in a given window
7662now runs the window-scroll-functions for that window.
7663
7664** The new function get-buffer-window-list returns a list of windows displaying
7665a buffer. The function is called with the buffer (a buffer object or a buffer
7666name) and two optional arguments specifying the minibuffer windows and frames
7667to search. Therefore this function takes optional args like next-window etc.,
7668and not get-buffer-window.
7669
7670** buffer-substring now runs the hook buffer-access-fontify-functions,
7671calling each function with two arguments--the range of the buffer
7672being accessed. buffer-substring-no-properties does not call them.
7673
7674If you use this feature, you should set the variable
7675buffer-access-fontified-property to a non-nil symbol, which is a
7676property name. Then, if all the characters in the buffer range have a
7677non-nil value for that property, the buffer-access-fontify-functions
7678are not called. When called, these functions should put a non-nil
7679property on the text that they fontify, so that they won't get called
7680over and over for the same text.
7681
7682** Changes in lisp-mnt.el
7683
7684*** The lisp-mnt package can now recognize file headers that are written
7685in the formats used by the `what' command and the RCS `ident' command:
7686
7687;; @(#) HEADER: text
7688;; $HEADER: text $
7689
7690in addition to the normal
7691
7692;; HEADER: text
7693
7694*** The commands lm-verify and lm-synopsis are now interactive. lm-verify
7695checks that the library file has proper sections and headers, and
7696lm-synopsis extracts first line "synopsis'"information.
7697\f
7698* For older news, see the file ONEWS.
7699
7700----------------------------------------------------------------------
7701Copyright information:
7702
404fa7d6 7703Copyright (C) 1996, 1997, 1998, 1999, 2000 Free Software Foundation, Inc.
a933dad1
DL
7704
7705 Permission is granted to anyone to make or distribute verbatim copies
7706 of this document as received, in any medium, provided that the
7707 copyright notice and this permission notice are preserved,
7708 thus giving the recipient permission to redistribute in turn.
7709
7710 Permission is granted to distribute modified versions
7711 of this document, or of portions of it,
7712 under the above conditions, provided also that they
7713 carry prominent notices stating who last changed them.
7714\f
7715Local variables:
7716mode: outline
7717paragraph-separate: "[ \f]*$"
7718end: