(syntax-code-table, syntax-flag-table): New variables.
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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.
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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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GM
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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760new user-option sort-numberic-base can be used to specify a default
761numeric base.
87be76f6 762
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DL
763** Ange-ftp allows you to specify of a port number in remote file
764names cleanly. It is appended to the host name, separated by a hash
765sign, e.g. `/foo@bar.org#666:mumble'. (This syntax comes from EFS.)
766
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GM
767** Shell script mode changes.
768
769Shell script mode (sh-script) can now indent scripts for shells
770derived from sh and rc. The indentation style is customizeable, and
771sh-script can attempt to "learn" the current buffer's style.
772
79214ddf
FP
773** Etags changes.
774
775*** In DOS, etags looks for file.cgz if it cannot find file.c.
776
aca0be23 777*** New option --ignore-case-regex is an alternative to --regex. It is now
8dc78b52
FP
778possible to bind a regexp to a language, by prepending the regexp with
779{lang}, where lang is one of the languages that `etags --help' prints out.
780This feature is useful especially for regex files, where each line contains
781a regular expression. The manual contains details.
aca0be23 782
79214ddf
FP
783*** In C and derived languages, etags creates tags for function
784declarations when given the --declarations option.
785
786*** In C++, tags are created for "operator". The tags have the form
aca0be23 787"operator+", without spaces between the keyword and the operator.
79214ddf
FP
788
789*** New language Ada: tags are functions, procedures, packages, tasks, and
790types.
791
792*** In Fortran, procedure is no more tagged.
793
794*** In Java, tags are created for "interface".
795
796*** In Lisp, "(defstruct (foo", "(defun (operator" and similar constructs
797are now tagged.
798
799*** In Perl, the --globals option tags global variables. my and local
800variables are tagged.
801
802*** New language Python: def and class at the beginning of a line are tags.
803
8dc78b52
FP
804*** .ss files are Scheme files, .pdb is Postscript with C syntax, .psw is
805for PSWrap.
79214ddf 806
f6737cde
GM
807** Changes in etags.el
808
809*** You can display additional output with M-x tags-apropos by setting
810the new variable tags-apropos-additional-actions.
811
812If non-nil, the variable's value should be a list of triples (TITLE
813FUNCTION TO-SEARCH). For each triple, M-x tags-apropos processes
814TO-SEARCH and lists tags from it. TO-SEARCH should be an alist,
815obarray, or symbol. If it is a symbol, the symbol's value is used.
816
817TITLE is a string to use to label the list of tags from TO-SEARCH.
818
819FUNCTION is a function to call when an entry is selected in the Tags
820List buffer. It is called with one argument, the selected symbol.
821
822A useful example value for this variable might be something like:
823
824 '(("Emacs Lisp" Info-goto-emacs-command-node obarray)
825 ("Common Lisp" common-lisp-hyperspec common-lisp-hyperspec-obarray)
826 ("SCWM" scwm-documentation scwm-obarray))
827
828*** The face tags-tag-face can be used to customize the appearance
829of tags in the output of M-x tags-apropos.
830
831*** Setting tags-apropos-verbose to a non-nil value displays the
832names of tags files in the *Tags List* buffer.
833
fbc164de
PE
834** Emacs now attempts to determine the initial language environment
835and preferred and locale coding systems systematically from the
836LC_ALL, LC_CTYPE, and LANG environment variables during startup.
837
59c1bf85
DL
838** New language environments `Latin-8' and `Latin-9'.
839These correspond respectively to the ISO character sets 8859-14
840(Celtic) and 8859-15 (updated Latin-1, with the Euro sign). There is
841currently no specific input method support for them.
842
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DL
843** Fortran mode has a new command `fortran-strip-sqeuence-nos' to
844remove text past column 72. The syntax class of `\' in Fortran is now
845appropriate for C-style escape sequences in strings.
846
847** SGML mode's default `sgml-validate-command' is now `nsgmls'.
848
6f8ea2ae
DL
849** A new command `view-emacs-problems' (C-h P) displays the PROBLEMS file.
850
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851** New modes and packages
852
5e5dff44
GM
853*** The new command M-x re-builder offers a convenient interface for
854authoring regular expressions with immediate visual feedback.
855
856The buffer from which the command was called becomes the target for
857the regexp editor popping up in a separate window. Matching text in
858the target buffer is immediately color marked during the editing.
859Each sub-expression of the regexp will show up in a different face so
860even complex regexps can be edited and verified on target data in a
861single step.
862
863On displays not supporting faces the matches instead blink like
864matching parens to make them stand out. On such a setup you will
865probably also want to use the sub-expression mode when the regexp
866contains such to get feedback about their respective limits.
867
f7136ee8
GM
868*** glasses-mode is a minor mode that makes
869unreadableIdentifiersLikeThis readable. It works as glasses, without
870actually modifying content of a buffer.
871
bbd9b566
GM
872*** The package ebnf2ps translates an EBNF to a syntactic chart in
873PostScript.
874
875Currently accepts ad-hoc EBNF, ISO EBNF and Bison/Yacc.
876
877The ad-hoc default EBNF syntax has the following elements:
878
879 ; comment (until end of line)
880 A non-terminal
881 "C" terminal
882 ?C? special
883 $A default non-terminal
884 $"C" default terminal
885 $?C? default special
886 A = B. production (A is the header and B the body)
887 C D sequence (C occurs before D)
888 C | D alternative (C or D occurs)
889 A - B exception (A excluding B, B without any non-terminal)
890 n * A repetition (A repeats n (integer) times)
891 (C) group (expression C is grouped together)
892 [C] optional (C may or not occurs)
893 C+ one or more occurrences of C
894 {C}+ one or more occurrences of C
895 {C}* zero or more occurrences of C
896 {C} zero or more occurrences of C
897 C / D equivalent to: C {D C}*
898 {C || D}+ equivalent to: C {D C}*
899 {C || D}* equivalent to: [C {D C}*]
900 {C || D} equivalent to: [C {D C}*]
901
902Please, see ebnf2ps documentation for EBNF syntax and how to use it.
903
99453a38
GM
904*** The package align.el will align columns within a region, using M-x
905align. Its mode-specific rules, based on regular expressions,
906determine where the columns should be split. In C and C++, for
907example, it will align variable names in declaration lists, or the
908equal signs of assignments.
909
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DL
910*** `paragraph-indent-minor-mode' is a new minor mode supporting
911paragraphs in the same style as `paragraph-indent-text-mode'.
912
6448a6b3
GM
913*** bs.el is a new package for buffer selection similar to
914list-buffers or electric-buffer-list. Use M-x bs-show to display a
915buffer menu with this package. You can use M-x bs-customize to
916customize the package.
917
249652b1
GM
918*** calculator.el is a small calculator package that is intended to
919replace desktop calculators such as xcalc and calc.exe. Actually, it
920is not too small - it has more features than most desktop calculators,
921and can be customized easily to get many more functions. It should
922not be confused with "calc" which is a much bigger mathematical tool
923which answers different needs.
924
3476b54a
GM
925*** The minor modes cwarn-mode and global-cwarn-mode highlights
926suspicious C and C++ constructions. Currently, assignments inside
927expressions, semicolon following `if', `for' and `while' (except, of
928course, after a `do .. while' statement), and C++ functions with
929reference parameters are recognized. The modes require font-lock mode
930to be enabled.
931
8964fec7
SM
932*** smerge-mode.el provides `smerge-mode', a simple minor-mode for files
933containing diff3-style conflict markers, such as generated by RCS.
934
a933dad1
DL
935*** 5x5.el is a simple puzzle game.
936
937*** hl-line.el provides a minor mode to highlight the current line.
938
939*** ansi-color.el translates ANSI terminal escapes into text-properties.
940
941*** delphi.el provides a major mode for editing the Delphi (Object
942Pascal) language.
943
944*** quickurl.el provides a simple method of inserting a URL based on
945the text at point.
946
947*** sql.el provides an interface to SQL data bases.
948
8d54eb69
DL
949*** fortune.el uses the fortune program to create mail/news signatures.
950
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DL
951*** whitespace.el ???
952
ebcfda83
GM
953*** PostScript mode (ps-mode) is a new major mode for editing PostScript
954files. It offers: interaction with a PostScript interpreter, including
955(very basic) error handling; fontification, easily customizable for
956interpreter messages; auto-indentation; insertion of EPSF templates and
957often used code snippets; viewing of BoundingBox; commenting out /
958uncommenting regions; conversion of 8bit characters to PostScript octal
959codes. All functionality is accessible through a menu.
960
961*** delim-col helps to prettify columns in a text region or rectangle.
962
963Here is an example of columns:
964
965horse apple bus
966dog pineapple car EXTRA
967porcupine strawberry airplane
968
969Doing the following settings:
970
971 (setq delimit-columns-str-before "[ ")
972 (setq delimit-columns-str-after " ]")
973 (setq delimit-columns-str-separator ", ")
974 (setq delimit-columns-separator "\t")
975
976
977Selecting the lines above and typing:
978
979 M-x delimit-columns-region
980
981It results:
982
983[ horse , apple , bus , ]
984[ dog , pineapple , car , EXTRA ]
985[ porcupine, strawberry, airplane, ]
986
987delim-col has the following options:
988
989 delimit-columns-str-before Specify a string to be inserted
990 before all columns.
991
992 delimit-columns-str-separator Specify a string to be inserted
993 between each column.
994
995 delimit-columns-str-after Specify a string to be inserted
996 after all columns.
997
998 delimit-columns-separator Specify a regexp which separates
999 each column.
1000
1001delim-col has the following commands:
1002
1003 delimit-columns-region Prettify all columns in a text region.
1004 delimit-columns-rectangle Prettify all columns in a text rectangle.
1005
f507826c
GM
1006*** The package recentf.el maintains a menu for visiting files that
1007were operated on recently. When enabled, a new "Open Recent" submenu
1008is displayed in the "Files" menu.
1009
1010The recent files list is automatically saved across Emacs sessions.
1011
1012To enable/disable recentf use M-x recentf-mode.
1013
1014To enable recentf at Emacs startup use
1015M-x customize-variable RET recentf-mode RET.
1016
1017To change the number of recent files displayed and others options use
1018M-x customize-group RET recentf RET.
1019
8062f458
DL
1020*** elide-head.el provides a mechanism for eliding boilerplate header
1021text.
1022
36e24b82 1023*** footnote.el provides `footnote-mode', a minor mode supporting use
91735437
DL
1024of footnotes. It is intended for use with Message mode, but isn't
1025specific to Message mode.
1026
36e24b82
DL
1027*** diff-mode.el provides `diff-mode', a major mode for
1028viewing/editing context diffs (patches). It is selected for files
1029with extension `.diff', `.diffs', `.patch' and `.rej'.
1030
aaa659ef
DL
1031*** EUDC, the Emacs Unified Directory Client, provides a common user
1032interface to access directory servers using different directory
1033protocols. It has a separate manual.
1034
eee54b0e
DL
1035*** autoconf.el provides a major mode for editing configure.in files
1036for Autoconf, selected automatically.
1037
aaa659ef
DL
1038*** windmove.el
1039
a933dad1
DL
1040** Withdrawn packages
1041
1042*** mldrag.el has been removed. mouse.el provides the same
1043functionality with aliases for the mldrag functions.
25a81338 1044
3261c1d8
DL
1045*** eval-reg.el has been obsoleted by changes to edebug.el and removed.
1046
1047*** ph.el has been obsoleted by EUDC and removed.
a933dad1
DL
1048\f
1049* Lisp changes in Emacs 21.1 (see following page for display-related features)
1050
1051Note that +++ before an item means the Lisp manual has been updated.
1052--- means that I have decided it does not need to be in the Lisp manual.
1053When you add a new item, please add it without either +++ or ---
1054so I will know I still need to look at it -- rms.
1055
1fa28578
GM
1056** Emacs' reader supports CL read syntax for integers in bases
1057other than 10.
1058
1059*** `#BINTEGER' or `#bINTEGER' reads INTEGER in binary (radix 2).
1060INTEGER optionally contains a sign.
1061
1062 #b1111
1063 => 15
1064 #b-1111
1065 => -15
1066
1067*** `#OINTEGER' or `#oINTEGER' reads INTEGER in octal (radix 8).
1068
1069 #o666
1070 => 438
1071
1072*** `#XINTEGER' or `#xINTEGER' reads INTEGER in hexadecimal (radix 16).
1073
1074 #xbeef
1075 => 48815
1076
1077*** `#RADIXrINTEGER' reads INTEGER in radix RADIX, 2 <= RADIX <= 36.
1078
1079 #2R-111
1080 => -7
1081 #25rah
1082 => 267
1083
e9b4e5ff
GM
1084** The function documentation-property now evaluates the value of
1085the given property to obtain a a string if it doesn't refer to etc/DOC
1086and isn't a string.
1087
16ce590d
DL
1088+++
1089** The last argument of `define-key-after' defaults to t for convenience.
1090
73825616 1091** The new function `replace-regexp-in-string' replaces all matches
16ce590d
DL
1092for a regexp in a string.
1093
1094** `mouse-position' now runs the abnormal hook
1095`mouse-position-function'.
1096
723e779c
GM
1097** The function string-to-number now returns a float for numbers
1098that don't fit into a Lisp integer.
1099
d1e103b2
GM
1100** The variable keyword-symbols-constants-flag has been removed.
1101Keywords are now always considered constants.
1102
31047e0d
DL
1103+++
1104** The new function `delete-and-extract-region' deletes text and
1105returns it.
1106
7a85e4df
GM
1107** The function `clear-this-command-keys' now also clears the vector
1108returned by function `recent-keys'.
1109
02b14400
RS
1110+++
1111** Variables `beginning-of-defun-function' and `end-of-defun-function'
1112can be used to define handlers for the functions that find defuns.
1113Major modes can define these locally instead of rebinding M-C-a
1114etc. if the normal conventions for defuns are not appropriate for the
1115mode.
404fa7d6 1116
02b14400 1117+++
8964fec7
SM
1118** easy-mmode-define-minor-mode now takes an additional BODY argument
1119and is renamed `define-minor-mode'.
1120
02b14400
RS
1121+++
1122** If an abbrev has a hook function which is a symbol, and that symbol
1123has a non-nil `no-self-insert' property, the return value of the hook
1124function specifies whether an expansion has been done or not. If it
1125returns nil, abbrev-expand also returns nil, meaning "no expansion has
1126been performed."
1127
1128When abbrev expansion is done by typing a self-inserting character,
1129and the abbrev has a hook with the `no-self-insert' property, and the
1130hook function returns non-nil meaning expansion has been done,
1131then the self-inserting character is not inserted.
ef961722 1132
02b14400 1133+++
81da8b32
GM
1134** The function `intern-soft' now accepts a symbol as first argument.
1135In this case, that exact symbol is looked up in the specified obarray,
1136and the function's value is nil if it is not found.
1137
02b14400 1138+++
9e207b90
GM
1139** The new macro `with-syntax-table' can be used to evaluate forms
1140with the syntax table of the current buffer temporarily set to a
1141specified table.
1142
1143 (with-syntax-table TABLE &rest BODY)
1144
1145Evaluate BODY with syntax table of current buffer set to a copy of
03d9c64c
GM
1146TABLE. The current syntax table is saved, BODY is evaluated, and the
1147saved table is restored, even in case of an abnormal exit. Value is
1148what BODY returns.
9e207b90 1149
02b14400 1150+++
d7f89643 1151** Regular expressions now support intervals \{n,m\} as well as
95cd4c40 1152Perl's shy-groups \(?:...\) and non-greedy *? +? and ?? operators.
8964fec7 1153
02b14400 1154+++
dde9e75a
GM
1155** The optional argument BUFFER of function file-local-copy has been
1156removed since it wasn't used by anything.
1157
02b14400 1158+++
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GM
1159** The file name argument of function `file-locked-p' is now required
1160instead of being optional.
1161
02b14400 1162+++
d20679eb
GM
1163** The new built-in error `text-read-only' is signaled when trying to
1164modify read-only text.
1165
02b14400 1166+++
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PE
1167** New functions and variables for locales.
1168
1169The new variable `locale-coding-system' specifies how to encode and
1170decode strings passed to low-level message functions like strerror and
b718982a
PE
1171time functions like strftime. The new variables
1172`system-messages-locale' and `system-time-locale' give the system
1173locales to be used when invoking these two types of functions.
fbc164de
PE
1174
1175The new function `set-locale-environment' sets the language
1176environment, preferred coding system, and locale coding system from
1177the system locale as specified by the LC_ALL, LC_CTYPE, and LANG
b718982a
PE
1178environment variables. Normally, it is invoked during startup and need
1179not be invoked thereafter. It uses the new variables
1180`locale-language-names', `locale-charset-language-names', and
1181`locale-preferred-coding-systems' to make its decisions.
fbc164de 1182
02b14400 1183+++
863476d1
SM
1184** syntax tables now understand nested comments.
1185To declare a comment syntax as allowing nesting, just add an `n'
1186modifier to either of the characters of the comment end and the comment
1187start sequences.
1188
02b14400 1189+++
ef6d912c
GM
1190** The function `pixmap-spec-p' has been renamed `bitmap-spec-p'
1191because `bitmap' is more in line with the usual X terminology.
1192
02b14400 1193+++
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DL
1194** New function `propertize'
1195
1196The new function `propertize' can be used to conveniently construct
1197strings with text properties.
1198
1199- Function: propertize STRING &rest PROPERTIES
1200
1201Value is a copy of STRING with text properties assigned as specified
1202by PROPERTIES. PROPERTIES is a sequence of pairs PROPERTY VALUE, with
1203PROPERTY being the name of a text property and VALUE being the
1204specified value of that property. Example:
1205
1206 (propertize "foo" 'face 'bold 'read-only t)
1207
1208+++
1209** push and pop macros.
1210
02b14400
RS
1211Simple versions of the push and pop macros of Common Lisp
1212are now defined in Emacs Lisp. These macros allow only symbols
a933dad1
DL
1213as the place that holds the list to be changed.
1214
1215(push NEWELT LISTNAME) add NEWELT to the front of LISTNAME's value.
1216(pop LISTNAME) return first elt of LISTNAME, and remove it
1217 (thus altering the value of LISTNAME).
1218
02b14400
RS
1219** New dolist and dotimes macros.
1220
6c7fd5aa
RS
1221Simple versions of the dolist and dotimes macros of Common Lisp
1222are now defined in Emacs Lisp.
02b14400
RS
1223
1224(dolist (VAR LIST [RESULT]) BODY...)
1225 Execute body once for each element of LIST,
1226 using the variable VAR to hold the current element.
1227 Then return the value of RESULT, or nil if RESULT is omitted.
1228
1229(dotimes (VAR COUNT [RESULT]) BODY...)
1230 Execute BODY with VAR bound to successive integers running from 0,
1231 inclusive, to COUNT, exclusive.
1232 Then return the value of RESULT, or nil if RESULT is omitted.
1233
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1234+++
1235** Regular expressions now support Posix character classes such
1236as [:alpha:], [:space:] and so on.
1237
1238[:digit:] matches 0 through 9
1239[:cntrl:] matches ASCII control characters
1240[:xdigit:] matches 0 through 9, a through f and A through F.
1241[:blank:] matches space and tab only
1242[:graph:] matches graphic characters--everything except ASCII control chars,
1243 space, and DEL.
1244[:print:] matches printing characters--everything except ASCII control chars
1245 and DEL.
1246[:alnum:] matches letters and digits.
1247 (But at present, for multibyte characters,
1248 it matches anything that has word syntax.)
1249[:alpha:] matches letters.
1250 (But at present, for multibyte characters,
1251 it matches anything that has word syntax.)
1252[:ascii:] matches ASCII (unibyte) characters.
1253[:nonascii:] matches non-ASCII (multibyte) characters.
1254[:lower:] matches anything lower-case.
1255[:punct:] matches punctuation.
1256 (But at present, for multibyte characters,
1257 it matches anything that has non-word syntax.)
1258[:space:] matches anything that has whitespace syntax.
1259[:upper:] matches anything upper-case.
1260[:word:] matches anything that has word syntax.
1261
1262+++
1263** Emacs now has built-in hash tables.
1264
1265The following functions are defined for hash tables:
1266
1267- Function: make-hash-table ARGS
1268
1269The argument list ARGS consists of keyword/argument pairs. All arguments
1270are optional. The following arguments are defined:
1271
1272:test TEST
1273
1274TEST must be a symbol specifying how to compare keys. Default is `eql'.
1275Predefined are `eq', `eql' and `equal'. If TEST is not predefined,
1276it must have been defined with `define-hash-table-test'.
1277
1278:size SIZE
1279
1280SIZE must be an integer > 0 giving a hint to the implementation how
1281many elements will be put in the hash table. Default size is 65.
1282
1283:rehash-size REHASH-SIZE
1284
1285REHASH-SIZE specifies by how much to grow a hash table once it becomes
1286full. If REHASH-SIZE is an integer, add that to the hash table's old
1287size to get the new size. Otherwise, REHASH-SIZE must be a float >
12881.0, and the new size is computed by multiplying REHASH-SIZE with the
1289old size. Default rehash size is 1.5.
1290
1291:rehash-threshold THRESHOLD
1292
1293THRESHOLD must be a float > 0 and <= 1.0 specifying when to resize the
1294hash table. It is resized when the ratio of (number of entries) /
1295(size of hash table) is >= THRESHOLD. Default threshold is 0.8.
1296
1297:weakness WEAK
1298
1299WEAK must be either nil, one of the symbols `key, `value', or t.
1300Entries are removed from weak tables during garbage collection if
1301their key and/or value are not referenced elsewhere outside of the
1302hash table. Default are non-weak hash tables.
1303
1304- Function: makehash &optional TEST
1305
1306Similar to make-hash-table, but only TEST can be specified.
1307
1308- Function: hash-table-p TABLE
1309
1310Returns non-nil if TABLE is a hash table object.
1311
1312- Function: copy-hash-table TABLE
1313
1314Returns a copy of TABLE. Only the table itself is copied, keys and
1315values are shared.
1316
1317- Function: hash-table-count TABLE
1318
1319Returns the number of entries in TABLE.
1320
1321- Function: hash-table-rehash-size TABLE
1322
1323Returns the rehash size of TABLE.
1324
1325- Function: hash-table-rehash-threshold TABLE
1326
1327Returns the rehash threshold of TABLE.
1328
1329- Function: hash-table-rehash-size TABLE
1330
1331Returns the size of TABLE.
1332
1333- Function: hash-table-rehash-test TABLE
1334
1335Returns the test TABLE uses to compare keys.
1336
1337- Function: hash-table-weakness TABLE
1338
1339Returns the weakness specified for TABLE.
1340
1341- Function: clrhash TABLE
1342
1343Clear TABLE.
1344
1345- Function: gethash KEY TABLE &optional DEFAULT
1346
1347Look up KEY in TABLE and return its associated VALUE or DEFAULT if
1348not found.
1349
79214ddf 1350- Function: puthash KEY VALUE TABLE
a933dad1
DL
1351
1352Associate KEY with VALUE in TABLE. If KEY is already associated with
1353another value, replace the old value with VALUE.
1354
1355- Function: remhash KEY TABLE
1356
1357Remove KEY from TABLE if it is there.
1358
1359- Function: maphash FUNCTION TABLE
1360
1361Call FUNCTION for all elements in TABLE. FUNCTION must take two
1362arguments KEY and VALUE.
1363
1364- Function: sxhash OBJ
1365
1366Return a hash code for Lisp object OBJ.
1367
1368- Function: define-hash-table-test NAME TEST-FN HASH-FN
1369
1370Define a new hash table test named NAME. If NAME is specified as
1371a test in `make-hash-table', the table created will use TEST-FN for
79214ddf 1372comparing keys, and HASH-FN to compute hash codes for keys. Test
a933dad1
DL
1373and hash function are stored as symbol property `hash-table-test'
1374of NAME with a value of (TEST-FN HASH-FN).
1375
1376TEST-FN must take two arguments and return non-nil if they are the same.
1377
1378HASH-FN must take one argument and return an integer that is the hash
1379code of the argument. The function should use the whole range of
1380integer values for hash code computation, including negative integers.
1381
1382Example: The following creates a hash table whose keys are supposed to
1383be strings that are compared case-insensitively.
1384
1385 (defun case-fold-string= (a b)
1386 (compare-strings a nil nil b nil nil t))
1387
1388 (defun case-fold-string-hash (a)
1389 (sxhash (upcase a)))
1390
79214ddf 1391 (define-hash-table-test 'case-fold 'case-fold-string=
a933dad1
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1392 'case-fold-string-hash))
1393
1394 (make-hash-table :test 'case-fold)
1395
1396+++
1397** The Lisp reader handles circular structure.
1398
1399It now works to use the #N= and #N# constructs to represent
1400circular structures. For example, #1=(a . #1#) represents
1401a cons cell which is its own cdr.
1402
1403+++
1404** The Lisp printer handles circular structure.
1405
1406If you bind print-circle to a non-nil value, the Lisp printer outputs
1407#N= and #N# constructs to represent circular and shared structure.
1408
a933dad1
DL
1409+++
1410** If the second argument to `move-to-column' is anything but nil or
1411t, that means replace a tab with spaces if necessary to reach the
1412specified column, but do not add spaces at the end of the line if it
1413is too short to reach that column.
1414
1415+++
1416** perform-replace has a new feature: the REPLACEMENTS argument may
1417now be a cons cell (FUNCTION . DATA). This means to call FUNCTION
1418after each match to get the replacement text. FUNCTION is called with
1419two arguments: DATA, and the number of replacements already made.
1420
1421If the FROM-STRING contains any upper-case letters,
1422perform-replace also turns off `case-fold-search' temporarily
1423and inserts the replacement text without altering case in it.
1424
1425+++
1426** The function buffer-size now accepts an optional argument
1427to specify which buffer to return the size of.
1428
1429+++
1430** The calendar motion commands now run the normal hook
1431calendar-move-hook after moving point.
1432
1433+++
1434** The new variable small-temporary-file-directory specifies a
1435directory to use for creating temporary files that are likely to be
1436small. (Certain Emacs features use this directory.) If
1437small-temporary-file-directory is nil, they use
1438temporary-file-directory instead.
1439
1440+++
1441** The variable `inhibit-modification-hooks', if non-nil, inhibits all
1442the hooks that track changes in the buffer. This affects
1443`before-change-functions' and `after-change-functions', as well as
1444hooks attached to text properties and overlay properties.
1445
1446+++
1447** assoc-delete-all is a new function that deletes all the
1448elements of an alist which have a particular value as the car.
1449
1450+++
1451** make-temp-file provides a more reliable way to create a temporary file.
1452
1453make-temp-file is used like make-temp-name, except that it actually
1454creates the file before it returns. This prevents a timing error,
1455ensuring that no other job can use the same name for a temporary file.
1456
1457+++
1458** New exclusive-open feature in `write-region'
1459
1460The optional seventh arg is now called MUSTBENEW. If non-nil, it insists
1461on a check for an existing file with the same name. If MUSTBENEW
1462is `excl', that means to get an error if the file already exists;
1463never overwrite. If MUSTBENEW is neither nil nor `excl', that means
1464ask for confirmation before overwriting, but do go ahead and
1465overwrite the file if the user gives confirmation.
1466
1467If the MUSTBENEW argument in `write-region' is `excl',
1468that means to use a special feature in the `open' system call
1469to get an error if the file exists at that time.
1470The error reported is `file-already-exists'.
1471
1472+++
1473** Function `format' now handles text properties.
1474
1475Text properties of the format string are applied to the result string.
1476If the result string is longer than the format string, text properties
1477ending at the end of the format string are extended to the end of the
1478result string.
1479
1480Text properties from string arguments are applied to the result
1481string where arguments appear in the result string.
1482
1483Example:
1484
1485 (let ((s1 "hello, %s")
1486 (s2 "world"))
1487 (put-text-property 0 (length s1) 'face 'bold s1)
1488 (put-text-property 0 (length s2) 'face 'italic s2)
b246b1f6 1489 (format s1 s2))
a933dad1
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1490
1491results in a bold-face string with an italic `world' at the end.
1492
1493+++
1494** Messages can now be displayed with text properties.
1495
1496Text properties are handled as described above for function `format'.
1497The following example displays a bold-face message with an italic
1498argument in it.
1499
1500 (let ((msg "hello, %s!")
1501 (arg "world"))
1502 (put-text-property 0 (length msg) 'face 'bold msg)
1503 (put-text-property 0 (length arg) 'face 'italic arg)
1504 (message msg arg))
1505
1506+++
1507** Sound support
1508
1509Emacs supports playing sound files on GNU/Linux and the free BSDs
1510(Voxware driver and native BSD driver, aka as Luigi's driver).
1511
1512Currently supported file formats are RIFF-WAVE (*.wav) and Sun Audio
1513(*.au). You must configure Emacs with the option `--with-sound=yes'
1514to enable sound support.
1515
1516Sound files can be played by calling (play-sound SOUND). SOUND is a
1517list of the form `(sound PROPERTY...)'. The function is only defined
1518when sound support is present for the system on which Emacs runs. The
1519functions runs `play-sound-functions' with one argument which is the
1520sound to play, before playing the sound.
1521
1522The following sound properties are supported:
1523
1524- `:file FILE'
1525
1526FILE is a file name. If FILE isn't an absolute name, it will be
1527searched relative to `data-directory'.
1528
6fb40beb
GM
1529- `:data DATA'
1530
1531DATA is a string containing sound data. Either :file or :data
1532may be present, but not both.
1533
a933dad1
DL
1534- `:volume VOLUME'
1535
1536VOLUME must be an integer in the range 0..100 or a float in the range
15370..1. This property is optional.
1538
1539Other properties are ignored.
1540
1541** `multimedia' is a new Finder keyword and Custom group.
356673d4
DL
1542
1543** keywordp is a new predicate to test efficiently for an object being
1544a keyword symbol.
fc91dc2d
GM
1545
1546** Changes to garbage collection
1547
1548*** The function garbage-collect now additionally returns the number
1549of live and free strings.
1550
1551*** There is a new variable `strings-consed' holding the number of
1552strings that have been consed so far.
1553
a933dad1
DL
1554\f
1555* New Lisp-level Display features in Emacs 21.1
1556
1557Note that +++ before an item means the Lisp manual has been updated.
1558--- means that I have decided it does not need to be in the Lisp manual.
1559When you add a new item, please add it without either +++ or ---
1560so I will know I still need to look at it -- rms.
1561
1562** New face implementation.
1563
1564Emacs faces have been reimplemented from scratch. They don't use XLFD
1565font names anymore and face merging now works as expected.
1566
1567+++
1568*** New faces.
1569
1570Each face can specify the following display attributes:
1571
1572 1. Font family or fontset alias name.
79214ddf 1573
a933dad1
DL
1574 2. Relative proportionate width, aka character set width or set
1575 width (swidth), e.g. `semi-compressed'.
79214ddf 1576
a933dad1 1577 3. Font height in 1/10pt
79214ddf 1578
a933dad1 1579 4. Font weight, e.g. `bold'.
79214ddf 1580
a933dad1 1581 5. Font slant, e.g. `italic'.
79214ddf 1582
a933dad1 1583 6. Foreground color.
79214ddf 1584
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DL
1585 7. Background color.
1586
1587 8. Whether or not characters should be underlined, and in what color.
1588
1589 9. Whether or not characters should be displayed in inverse video.
1590
1591 10. A background stipple, a bitmap.
1592
1593 11. Whether or not characters should be overlined, and in what color.
1594
1595 12. Whether or not characters should be strike-through, and in what
1596 color.
1597
1598 13. Whether or not a box should be drawn around characters, its
1599 color, the width of the box lines, and 3D appearance.
1600
1601Faces are frame-local by nature because Emacs allows to define the
1602same named face (face names are symbols) differently for different
1603frames. Each frame has an alist of face definitions for all named
1604faces. The value of a named face in such an alist is a Lisp vector
1605with the symbol `face' in slot 0, and a slot for each each of the face
1606attributes mentioned above.
1607
1608There is also a global face alist `face-new-frame-defaults'. Face
1609definitions from this list are used to initialize faces of newly
1610created frames.
79214ddf 1611
a933dad1
DL
1612A face doesn't have to specify all attributes. Those not specified
1613have a nil value. Faces specifying all attributes are called
1614`fully-specified'.
1615
1616+++
1617*** Face merging.
1618
1619The display style of a given character in the text is determined by
1620combining several faces. This process is called `face merging'. Any
1621aspect of the display style that isn't specified by overlays or text
1622properties is taken from the `default' face. Since it is made sure
1623that the default face is always fully-specified, face merging always
1624results in a fully-specified face.
1625
1626+++
1627*** Face realization.
1628
1629After all face attributes for a character have been determined by
1630merging faces of that character, that face is `realized'. The
1631realization process maps face attributes to what is physically
1632available on the system where Emacs runs. The result is a `realized
1633face' in form of an internal structure which is stored in the face
1634cache of the frame on which it was realized.
1635
1636Face realization is done in the context of the charset of the
1637character to display because different fonts and encodings are used
1638for different charsets. In other words, for characters of different
1639charsets, different realized faces are needed to display them.
1640
1641Except for composite characters, faces are always realized for a
1642specific character set and contain a specific font, even if the face
1643being realized specifies a fontset. The reason is that the result of
1644the new font selection stage is better than what can be done with
1645statically defined font name patterns in fontsets.
1646
1647In unibyte text, Emacs' charsets aren't applicable; function
1648`char-charset' reports ASCII for all characters, including those >
16490x7f. The X registry and encoding of fonts to use is determined from
1650the variable `face-default-registry' in this case. The variable is
1651initialized at Emacs startup time from the font the user specified for
1652Emacs.
1653
1654Currently all unibyte text, i.e. all buffers with
1655`enable-multibyte-characters' nil are displayed with fonts of the same
1656registry and encoding `face-default-registry'. This is consistent
1657with the fact that languages can also be set globally, only.
1658
1659++++
1660**** Clearing face caches.
1661
1662The Lisp function `clear-face-cache' can be called to clear face caches
1663on all frames. If called with a non-nil argument, it will also unload
1664unused fonts.
1665
1666+++
1667*** Font selection.
79214ddf 1668
a933dad1
DL
1669Font selection tries to find the best available matching font for a
1670given (charset, face) combination. This is done slightly differently
1671for faces specifying a fontset, or a font family name.
1672
1673If the face specifies a fontset name, that fontset determines a
1674pattern for fonts of the given charset. If the face specifies a font
1675family, a font pattern is constructed. Charset symbols have a
1676property `x-charset-registry' for that purpose that maps a charset to
1677an XLFD registry and encoding in the font pattern constructed.
1678
1679Available fonts on the system on which Emacs runs are then matched
1680against the font pattern. The result of font selection is the best
1681match for the given face attributes in this font list.
1682
1683Font selection can be influenced by the user.
1684
1685The user can specify the relative importance he gives the face
1686attributes width, height, weight, and slant by setting
1687face-font-selection-order (faces.el) to a list of face attribute
1688names. The default is (:width :height :weight :slant), and means
1689that font selection first tries to find a good match for the font
1690width specified by a face, then---within fonts with that width---tries
1691to find a best match for the specified font height, etc.
1692
1693Setting `face-alternative-font-family-alist' allows the user to
1694specify alternative font families to try if a family specified by a
1695face doesn't exist.
1696
1697+++
1698**** Scalable fonts
1699
1700Emacs can make use of scalable fonts but doesn't do so by default,
1701since the use of too many or too big scalable fonts may crash XFree86
1702servers.
1703
1704To enable scalable font use, set the variable
b246b1f6 1705`scalable-fonts-allowed'. A value of nil, the default, means never use
a933dad1
DL
1706scalable fonts. A value of t means any scalable font may be used.
1707Otherwise, the value must be a list of regular expressions. A
1708scalable font may then be used if it matches a regular expression from
1709that list. Example:
1710
1711 (setq scalable-fonts-allowed '("muleindian-2$"))
1712
1713allows the use of scalable fonts with registry `muleindian-2'.
1714
1715+++
1716*** Functions and variables related to font selection.
1717
1718- Function: x-family-fonts &optional FAMILY FRAME
1719
1720Return a list of available fonts of family FAMILY on FRAME. If FAMILY
1721is omitted or nil, list all families. Otherwise, FAMILY must be a
1722string, possibly containing wildcards `?' and `*'.
1723
1724If FRAME is omitted or nil, use the selected frame. Each element of
1725the result is a vector [FAMILY WIDTH POINT-SIZE WEIGHT SLANT FIXED-P
1726FULL REGISTRY-AND-ENCODING]. FAMILY is the font family name.
1727POINT-SIZE is the size of the font in 1/10 pt. WIDTH, WEIGHT, and
1728SLANT are symbols describing the width, weight and slant of the font.
1729These symbols are the same as for face attributes. FIXED-P is non-nil
1730if the font is fixed-pitch. FULL is the full name of the font, and
1731REGISTRY-AND-ENCODING is a string giving the registry and encoding of
1732the font. The result list is sorted according to the current setting
1733of the face font sort order.
1734
79214ddf 1735- Function: x-font-family-list
a933dad1
DL
1736
1737Return a list of available font families on FRAME. If FRAME is
1738omitted or nil, use the selected frame. Value is a list of conses
1739(FAMILY . FIXED-P) where FAMILY is a font family, and FIXED-P is
1740non-nil if fonts of that family are fixed-pitch.
1741
1742- Variable: font-list-limit
1743
1744Limit for font matching. If an integer > 0, font matching functions
1745won't load more than that number of fonts when searching for a
1746matching font. The default is currently 100.
1747
1748+++
1749*** Setting face attributes.
1750
1751For the most part, the new face implementation is interface-compatible
1752with the old one. Old face attribute related functions are now
1753implemented in terms of the new functions `set-face-attribute' and
1754`face-attribute'.
1755
1756Face attributes are identified by their names which are keyword
1757symbols. All attributes can be set to `unspecified'.
1758
1759The following attributes are recognized:
1760
1761`:family'
1762
1763VALUE must be a string specifying the font family, e.g. ``courier'',
1764or a fontset alias name. If a font family is specified, wild-cards `*'
1765and `?' are allowed.
1766
1767`:width'
1768
1769VALUE specifies the relative proportionate width of the font to use.
1770It must be one of the symbols `ultra-condensed', `extra-condensed',
1771`condensed', `semi-condensed', `normal', `semi-expanded', `expanded',
1772`extra-expanded', or `ultra-expanded'.
1773
1774`:height'
1775
1776VALUE must be an integer specifying the height of the font to use in
17771/10 pt.
1778
1779`:weight'
1780
1781VALUE specifies the weight of the font to use. It must be one of the
1782symbols `ultra-bold', `extra-bold', `bold', `semi-bold', `normal',
1783`semi-light', `light', `extra-light', `ultra-light'.
1784
1785`:slant'
1786
1787VALUE specifies the slant of the font to use. It must be one of the
1788symbols `italic', `oblique', `normal', `reverse-italic', or
1789`reverse-oblique'.
1790
1791`:foreground', `:background'
1792
1793VALUE must be a color name, a string.
1794
1795`:underline'
1796
1797VALUE specifies whether characters in FACE should be underlined. If
1798VALUE is t, underline with foreground color of the face. If VALUE is
1799a string, underline with that color. If VALUE is nil, explicitly
1800don't underline.
1801
1802`:overline'
1803
1804VALUE specifies whether characters in FACE should be overlined. If
1805VALUE is t, overline with foreground color of the face. If VALUE is a
1806string, overline with that color. If VALUE is nil, explicitly don't
1807overline.
1808
1809`:strike-through'
1810
1811VALUE specifies whether characters in FACE should be drawn with a line
1812striking through them. If VALUE is t, use the foreground color of the
1813face. If VALUE is a string, strike-through with that color. If VALUE
1814is nil, explicitly don't strike through.
1815
1816`:box'
1817
1818VALUE specifies whether characters in FACE should have a box drawn
1819around them. If VALUE is nil, explicitly don't draw boxes. If
1820VALUE is t, draw a box with lines of width 1 in the foreground color
1821of the face. If VALUE is a string, the string must be a color name,
1822and the box is drawn in that color with a line width of 1. Otherwise,
1823VALUE must be a property list of the form `(:line-width WIDTH
1824:color COLOR :style STYLE)'. If a keyword/value pair is missing from
1825the property list, a default value will be used for the value, as
1826specified below. WIDTH specifies the width of the lines to draw; it
1827defaults to 1. COLOR is the name of the color to draw in, default is
1828the foreground color of the face for simple boxes, and the background
1829color of the face for 3D boxes. STYLE specifies whether a 3D box
1830should be draw. If STYLE is `released-button', draw a box looking
1831like a released 3D button. If STYLE is `pressed-button' draw a box
1832that appears like a pressed button. If STYLE is nil, the default if
1833the property list doesn't contain a style specification, draw a 2D
1834box.
1835
1836`:inverse-video'
1837
1838VALUE specifies whether characters in FACE should be displayed in
1839inverse video. VALUE must be one of t or nil.
1840
1841`:stipple'
1842
1843If VALUE is a string, it must be the name of a file of pixmap data.
1844The directories listed in the `x-bitmap-file-path' variable are
1845searched. Alternatively, VALUE may be a list of the form (WIDTH
1846HEIGHT DATA) where WIDTH and HEIGHT are the size in pixels, and DATA
1847is a string containing the raw bits of the bitmap. VALUE nil means
1848explicitly don't use a stipple pattern.
1849
1850For convenience, attributes `:family', `:width', `:height', `:weight',
1851and `:slant' may also be set in one step from an X font name:
1852
1853`:font'
1854
1855Set font-related face attributes from VALUE. VALUE must be a valid
1856XLFD font name. If it is a font name pattern, the first matching font
1857is used--this is for compatibility with the behavior of previous
1858versions of Emacs.
1859
1860For compatibility with Emacs 20, keywords `:bold' and `:italic' can
1861be used to specify that a bold or italic font should be used. VALUE
1862must be t or nil in that case. A value of `unspecified' is not allowed."
1863
1864Please see also the documentation of `set-face-attribute' and
1865`defface'.
1866
1867*** Face attributes and X resources
1868
1869The following X resource names can be used to set face attributes
1870from X resources:
1871
1872 Face attribute X resource class
1873-----------------------------------------------------------------------
1874 :family attributeFamily . Face.AttributeFamily
1875 :width attributeWidth Face.AttributeWidth
1876 :height attributeHeight Face.AttributeHeight
1877 :weight attributeWeight Face.AttributeWeight
1878 :slant attributeSlant Face.AttributeSlant
1879 foreground attributeForeground Face.AttributeForeground
1880 :background attributeBackground . Face.AttributeBackground
1881 :overline attributeOverline Face.AttributeOverline
1882 :strike-through attributeStrikeThrough Face.AttributeStrikeThrough
1883 :box attributeBox Face.AttributeBox
1884 :underline attributeUnderline Face.AttributeUnderline
1885 :inverse-video attributeInverse Face.AttributeInverse
1886 :stipple attributeStipple Face.AttributeStipple
79214ddf 1887 or attributeBackgroundPixmap
a933dad1
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1888 Face.AttributeBackgroundPixmap
1889 :font attributeFont Face.AttributeFont
1890 :bold attributeBold Face.AttributeBold
1891 :italic attributeItalic . Face.AttributeItalic
1892 :font attributeFont Face.AttributeFont
1893
1894+++
1895*** Text property `face'.
1896
1897The value of the `face' text property can now be a single face
1898specification or a list of such specifications. Each face
1899specification can be
1900
19011. A symbol or string naming a Lisp face.
1902
19032. A property list of the form (KEYWORD VALUE ...) where each
1904 KEYWORD is a face attribute name, and VALUE is an appropriate value
1905 for that attribute. Please see the doc string of `set-face-attribute'
1906 for face attribute names.
1907
19083. Conses of the form (FOREGROUND-COLOR . COLOR) or
1909 (BACKGROUND-COLOR . COLOR) where COLOR is a color name. This is
1910 for compatibility with previous Emacs versions.
1911
1912+++
1913** Support functions for colors on text-only terminals.
1914
acf3ecb7
EZ
1915The function `tty-color-define' can be used to define colors for use
1916on TTY and MSDOS frames. It maps a color name to a color number on
1917the terminal. Emacs defines a couple of common color mappings by
a933dad1 1918default. You can get defined colors with a call to
acf3ecb7 1919`defined-colors'. The function `tty-color-clear' can be
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DL
1920used to clear the mapping table.
1921
acf3ecb7
EZ
1922** Unified support for colors independent of frame type.
1923
1924The new functions `defined-colors', `color-defined-p', `color-values',
1925and `display-color-p' work for any type of frame. On frames whose
1926type is neither x nor w32, these functions transparently map X-style
1927color specifications to the closest colors supported by the frame
1928display. Lisp programs should use these new functions instead of the
1929old `x-defined-colors', `x-color-defined-p', `x-color-values', and
1930`x-display-color-p'. (The old function names are still available for
1931compatibility; they are now aliases of the new names.) Lisp programs
1932should no more look at the value of the variable window-system to
1933modify their color-related behavior.
1934
1935The primitives `color-gray-p' and `color-supported-p' also work for
1936any frame type.
1937
8a5719f0
EZ
1938** Platform-independent functions to describe display capabilities.
1939
1940The new functions `display-mouse-p', `display-popup-menus-p',
1941`display-graphic-p', `display-selections-p', `display-screens',
1942`display-pixel-width', `display-pixel-height', `display-mm-width',
1943`display-mm-height', `display-backing-store', `display-save-under',
1944`display-planes', `display-color-cells', `display-visual-class', and
1945`display-grayscale-p' describe the basic capabilities of a particular
1946display. Lisp programs should call these functions instead of testing
1947the value of the variables `window-system' or `system-type', or calling
1948platform-specific functions such as `x-display-pixel-width'.
1949
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1950+++
1951** The minibuffer prompt is now actually inserted in the minibuffer.
a933dad1 1952
463cac2d 1953This makes it possible to scroll through the prompt, if you want to.
a933dad1
DL
1954
1955The function minubuffer-prompt-end returns the current position of the
1956end of the minibuffer prompt, if the minibuffer is current.
1957Otherwise, it returns zero.
1958
463cac2d
GM
1959** New `field' abstraction in buffers.
1960
1961There is now code to support an abstraction called `fields' in emacs
1962buffers. A field is a contiguous region of text with the same `field'
1963text-property.
1964
9a9dfda8 1965Many emacs functions, such as forward-word, forward-sentence,
463cac2d 1966forward-paragraph, beginning-of-line, etc., stop moving when they come
9a9dfda8 1967to the boundary between fields; beginning-of-line and end-of-line will
463cac2d 1968not let the point move past the field boundary, but other movement
fc7ac24f
GM
1969commands continue into the next field if repeated. Stopping at field
1970boundaries can be suppressed programmatically by binding
1971`inhibit-field-text-motion' to a non-nil value around calls to these
1972functions.
463cac2d
GM
1973
1974Now that the minibuffer prompt is inserted into the minibuffer, it is in
9a9dfda8 1975a separate field from the user-input part of the buffer, so that common
463cac2d 1976editing commands treat the user's text separately from the prompt.
a933dad1 1977
9a9dfda8
GM
1978The following functions are defined for operating on fields:
1979
1980- Function: constrain-to-field NEW-POS OLD-POS &optional ESCAPE-FROM-EDGE ONLY-IN-LINE
1981
1982Return the position closest to NEW-POS that is in the same field as OLD-POS.
1983A field is a region of text with the same `field' property.
1984If NEW-POS is nil, then the current point is used instead, and set to the
1985constrained position if that is is different.
1986
1987If OLD-POS is at the boundary of two fields, then the allowable
1988positions for NEW-POS depends on the value of the optional argument
1989ESCAPE-FROM-EDGE: If ESCAPE-FROM-EDGE is nil, then NEW-POS is
1990constrained to the field that has the same `field' text-property
1991as any new characters inserted at OLD-POS, whereas if ESCAPE-FROM-EDGE
1992is non-nil, NEW-POS is constrained to the union of the two adjacent
1993fields.
1994
1995If the optional argument ONLY-IN-LINE is non-nil and constraining
1996NEW-POS would move it to a different line, NEW-POS is returned
1997unconstrained. This useful for commands that move by line, like
1998C-n or C-a, which should generally respect field boundaries
1999only in the case where they can still move to the right line.
2000
2001- Function: erase-field &optional POS
2002
2003Erases the field surrounding POS.
2004A field is a region of text with the same `field' property.
2005If POS is nil, the position of the current buffer's point is used.
2006
2007- Function: field-beginning &optional POS ESCAPE-FROM-EDGE
2008
2009Return the beginning of the field surrounding POS.
2010A field is a region of text with the same `field' property.
2011If POS is nil, the position of the current buffer's point is used.
2012If ESCAPE-FROM-EDGE is non-nil and POS is already at beginning of an
2013field, then the beginning of the *previous* field is returned.
2014
2015- Function: field-end &optional POS ESCAPE-FROM-EDGE
2016
2017Return the end of the field surrounding POS.
2018A field is a region of text with the same `field' property.
2019If POS is nil, the position of the current buffer's point is used.
2020If ESCAPE-FROM-EDGE is non-nil and POS is already at end of a field,
2021then the end of the *following* field is returned.
2022
2023- Function: field-string &optional POS
2024
2025Return the contents of the field surrounding POS as a string.
2026A field is a region of text with the same `field' property.
2027If POS is nil, the position of the current buffer's point is used.
2028
2029- Function: field-string-no-properties &optional POS
2030
2031Return the contents of the field around POS, without text-properties.
2032A field is a region of text with the same `field' property.
2033If POS is nil, the position of the current buffer's point is used.
2034
a933dad1
DL
2035+++
2036** Image support.
2037
2038Emacs can now display images. Images are inserted into text by giving
2039strings or buffer text a `display' text property containing one of
2040(AREA IMAGE) or IMAGE. The display of the `display' property value
2041replaces the display of the characters having that property.
2042
2043If the property value has the form (AREA IMAGE), AREA must be one of
2044`(margin left-margin)', `(margin right-margin)' or `(margin nil)'. If
2045AREA is `(margin nil)', IMAGE will be displayed in the text area of a
2046window, otherwise it will be displayed in the left or right marginal
2047area.
2048
2049IMAGE is an image specification.
2050
2051*** Image specifications
2052
2053Image specifications are lists of the form `(image PROPS)' where PROPS
2054is a property list whose keys are keyword symbols. Each
2055specifications must contain a property `:type TYPE' with TYPE being a
35a5514b
GM
2056symbol specifying the image type, e.g. `xbm'. Properties not
2057described below are ignored.
a933dad1
DL
2058
2059The following is a list of properties all image types share.
2060
2061`:ascent ASCENT'
2062
2063ASCENT must be a number in the range 0..100, and specifies the percentage
2064of the image's height to use for its ascent. Default is 50.
2065
2066`:margin MARGIN'
2067
79214ddf 2068MARGIN must be a number >= 0 specifying how many pixels to put as
a933dad1
DL
2069margin around the image. Default is 0.
2070
2071`:relief RELIEF'
2072
2073RELIEF is analogous to the `:relief' attribute of faces. Puts a relief
2074around an image.
2075
2076`:algorithm ALGO'
2077
2078Apply an image algorithm to the image before displaying it. ALGO must
2079be a symbol specifying the algorithm. Currently only `laplace' is
2080supported which applies a Laplace edge detection algorithm to an image
2081which is intended to display images "disabled."
2082
2083`:heuristic-mask BG'
2084
2085If BG is not nil, build a clipping mask for the image, so that the
2086background of a frame is visible behind the image. If BG is t,
2087determine the background color of the image by looking at the 4
2088corners of the image, assuming the most frequently occuring color from
2089the corners is the background color of the image. Otherwise, BG must
2090be a list `(RED GREEN BLUE)' specifying the color to assume for the
2091background of the image.
2092
2093`:file FILE'
2094
2095Load image from FILE. If FILE is not absolute after expanding it,
2096search for the image in `data-directory'. Some image types support
2097building images from data. When this is done, no `:file' property
2098may be present in the image specification.
2099
518df5c4
GM
2100`:data DATA'
2101
2102Get image data from DATA. (As of this writing, this is not yet
2103supported for image type `postscript'). Either :file or :data may be
2104present in an image specification, but not both. All image types
2105support strings as DATA, some types allow additional types of DATA.
2106
a933dad1
DL
2107*** Supported image types
2108
b246b1f6 2109**** XBM, image type `xbm'.
a933dad1
DL
2110
2111XBM images don't require an external library. Additional image
2112properties supported are
2113
2114`:foreground FG'
2115
2116FG must be a string specifying the image foreground color. Default
2117is the frame's foreground.
2118
2119`:background FG'
2120
2121BG must be a string specifying the image foreground color. Default is
2122the frame's background color.
2123
2124XBM images can be constructed from data instead of file. In this
2125case, the image specification must contain the following properties
2126instead of a `:file' property.
2127
2128`:width WIDTH'
2129
2130WIDTH specifies the width of the image in pixels.
2131
2132`:height HEIGHT'
2133
2134HEIGHT specifies the height of the image in pixels.
2135
2136`:data DATA'
2137
2138DATA must be either
2139
2140 1. a string large enough to hold the bitmap data, i.e. it must
2141 have a size >= (WIDTH + 7) / 8 * HEIGHT
2142
2143 2. a bool-vector of size >= WIDTH * HEIGHT
2144
2145 3. a vector of strings or bool-vectors, one for each line of the
2146 bitmap.
2147
2148**** XPM, image type `xpm'
2149
2150XPM images require the external library `libXpm', package
2151`xpm-3.4k.tar.gz', version 3.4k or later. Make sure the library is
2152found when Emacs is configured by supplying appropriate paths via
2153`--x-includes' and `--x-libraries'.
2154
2155Additional image properties supported are:
2156
2157`:color-symbols SYMBOLS'
2158
2159SYMBOLS must be a list of pairs (NAME . COLOR), with NAME being the
2160name of color as it appears in an XPM file, and COLOR being an X color
2161name.
2162
2163XPM images can be built from memory instead of files. In that case,
2164add a `:data' property instead of a `:file' property.
2165
a933dad1
DL
2166The XPM library uses libz in its implementation so that it is able
2167to display compressed images.
2168
2169**** PBM, image type `pbm'
2170
2171PBM images don't require an external library. Color, gray-scale and
2172mono images are supported. There are no additional image properties
2173defined.
2174
2175**** JPEG, image type `jpeg'
2176
2177Support for JPEG images requires the external library `libjpeg',
3bd37feb
GM
2178package `jpegsrc.v6a.tar.gz', or later. Additional image properties
2179are:
2180
a933dad1
DL
2181**** TIFF, image type `tiff'
2182
2183Support for TIFF images requires the external library `libtiff',
2184package `tiff-v3.4-tar.gz', or later. There are no additional image
2185properties defined.
2186
2187**** GIF, image type `gif'
2188
2189Support for GIF images requires the external library `libungif', package
2190`libungif-4.1.0', or later.
2191
2192Additional image properties supported are:
2193
2194`:index INDEX'
2195
2196INDEX must be an integer >= 0. Load image number INDEX from a
2197multi-image GIF file. An error is signalled if INDEX is too large.
2198
2199This could be used to implement limited support for animated GIFs.
2200For example, the following function displays a multi-image GIF file
2201at point-min in the current buffer, switching between sub-images
2202every 0.1 seconds.
2203
2204(defun show-anim (file max)
2205 "Display multi-image GIF file FILE which contains MAX subimages."
2206 (display-anim (current-buffer) file 0 max t))
2207
2208(defun display-anim (buffer file idx max first-time)
2209 (when (= idx max)
2210 (setq idx 0))
518df5c4 2211 (let ((img (create-image file nil nil :index idx)))
a933dad1
DL
2212 (save-excursion
2213 (set-buffer buffer)
2214 (goto-char (point-min))
2215 (unless first-time (delete-char 1))
2216 (insert-image img "x"))
2217 (run-with-timer 0.1 nil 'display-anim buffer file (1+ idx) max nil)))
2218
2219**** PNG, image type `png'
2220
2221Support for PNG images requires the external library `libpng',
2222package `libpng-1.0.2.tar.gz', or later. There are no additional image
2223properties defined.
2224
2225**** Ghostscript, image type `postscript'.
2226
2227Additional image properties supported are:
2228
2229`:pt-width WIDTH'
2230
2231WIDTH is width of the image in pt (1/72 inch). WIDTH must be an
b246b1f6 2232integer. This is a required property.
a933dad1
DL
2233
2234`:pt-height HEIGHT'
2235
2236HEIGHT specifies the height of the image in pt (1/72 inch). HEIGHT
b246b1f6 2237must be a integer. This is an required property.
a933dad1
DL
2238
2239`:bounding-box BOX'
2240
2241BOX must be a list or vector of 4 integers giving the bounding box of
2242the PS image, analogous to the `BoundingBox' comment found in PS
2243files. This is an required property.
2244
2245Part of the Ghostscript interface is implemented in Lisp. See
2246lisp/gs.el.
2247
2248*** Lisp interface.
2249
79214ddf
FP
2250The variable `image-types' contains a list of those image types
2251which are supported in the current configuration.
a933dad1
DL
2252
2253Images are stored in an image cache and removed from the cache when
2254they haven't been displayed for `image-cache-eviction-delay seconds.
2255The function `clear-image-cache' can be used to clear the image cache
2256manually.
2257
2258*** Simplified image API, image.el
2259
2260The new Lisp package image.el contains functions that simplify image
2261creation and putting images into text. The function `create-image'
2262can be used to create images. The macro `defimage' can be used to
2263define an image based on available image types. The functions
2264`put-image' and `insert-image' can be used to insert an image into a
2265buffer.
2266
2267+++
2268** Display margins.
2269
2270Windows can now have margins which are used for special text
2271and images.
2272
2273To give a window margins, either set the buffer-local variables
2274`left-margin-width' and `right-margin-width', or call
2275`set-window-margins'. The function `window-margins' can be used to
2276obtain the current settings. To make `left-margin-width' and
2277`right-margin-width' take effect, you must set them before displaying
2278the buffer in a window, or use `set-window-buffer' to force an update
2279of the display margins.
2280
2281You can put text in margins by giving it a `display' text property
2282containing a pair of the form `(LOCATION . VALUE)', where LOCATION is
2283one of `left-margin' or `right-margin' or nil. VALUE can be either a
2284string, an image specification or a stretch specification (see later
2285in this file).
2286
2287+++
2288** Help display
2289
2290Emacs displays short help messages in the echo area, when the mouse
2291moves over a tool-bar item or a piece of text that has a text property
2292`help-echo'. This feature also applies to strings in the mode line
2293that have a `help-echo' property.
2294
2295The value of the `help-echo' property must be a string. For tool-bar
2296items, their key definition is used to determine the help to display.
2297If their definition contains a property `:help FORM', FORM is
2298evaluated to determine the help string. Otherwise, the caption of the
2299tool-bar item is used.
2300
2301The hook `show-help-function' can be set to a function that displays
2302help differently. For example, enabling a tooltip window causes the
2303help display to appear there instead of in the echo area.
2304
2305+++
2306** Vertical fractional scrolling.
2307
2308The display of text in windows can be scrolled smoothly in pixels.
2309This is useful, for example, for making parts of large images visible.
2310
2311The function `window-vscroll' returns the current value of vertical
2312scrolling, a non-negative fraction of the canonical character height.
2313The function `set-window-vscroll' can be used to set the vertical
2314scrolling value. Here is an example of how these function might be
2315used.
2316
79214ddf
FP
2317 (global-set-key [A-down]
2318 #'(lambda ()
a933dad1 2319 (interactive)
79214ddf 2320 (set-window-vscroll (selected-window)
a933dad1 2321 (+ 0.5 (window-vscroll)))))
79214ddf 2322 (global-set-key [A-up]
a933dad1
DL
2323 #'(lambda ()
2324 (interactive)
79214ddf 2325 (set-window-vscroll (selected-window)
a933dad1
DL
2326 (- (window-vscroll) 0.5)))))
2327
2328+++
2329** New hook `fontification-functions'.
2330
2331Functions from `fontification-functions' are called from redisplay
2332when it encounters a region of text that is not yet fontified. This
2333variable automatically becomes buffer-local when set. Each function
2334is called with one argument, POS.
2335
2336At least one of the hook functions should fontify one or more
2337characters starting at POS in the current buffer. It should mark them
2338as fontified by giving them a non-nil value of the `fontified' text
2339property. It may be reasonable for these functions to check for the
2340`fontified' property and not put it back on, but they do not have to.
2341
2342+++
2343** Tool bar support.
2344
2345Emacs supports a tool bar at the top of a frame under X. The frame
2346parameter `tool-bar-lines' (X resource "toolBar", class "ToolBar")
2347controls how may lines to reserve for the tool bar. A zero value
2348suppresses the tool bar. If the value is non-zero and
2349`auto-resize-tool-bars' is non-nil the tool bar's size will be changed
2350automatically so that all tool bar items are visible.
2351
2352*** Tool bar item definitions
2353
2354Tool bar items are defined using `define-key' with a prefix-key
2355`tool-bar'. For example `(define-key global-map [tool-bar item1] ITEM)'
2356where ITEM is a list `(menu-item CAPTION BINDING PROPS...)'.
79214ddf 2357
a933dad1
DL
2358CAPTION is the caption of the item, If it's not a string, it is
2359evaluated to get a string. The caption is currently not displayed in
2360the tool bar, but it is displayed if the item doesn't have a `:help'
2361property (see below).
79214ddf 2362
a933dad1
DL
2363BINDING is the tool bar item's binding. Tool bar items with keymaps as
2364binding are currently ignored.
2365
2366The following properties are recognized:
2367
2368`:enable FORM'.
79214ddf 2369
a933dad1
DL
2370FORM is evaluated and specifies whether the tool bar item is enabled
2371or disabled.
79214ddf 2372
a933dad1 2373`:visible FORM'
79214ddf 2374
a933dad1 2375FORM is evaluated and specifies whether the tool bar item is displayed.
79214ddf 2376
a933dad1
DL
2377`:filter FUNCTION'
2378
2379FUNCTION is called with one parameter, the same list BINDING in which
2380FUNCTION is specified as the filter. The value FUNCTION returns is
2381used instead of BINDING to display this item.
79214ddf 2382
a933dad1
DL
2383`:button (TYPE SELECTED)'
2384
2385TYPE must be one of `:radio' or `:toggle'. SELECTED is evaluated
2386and specifies whether the button is selected (pressed) or not.
79214ddf 2387
a933dad1
DL
2388`:image IMAGES'
2389
2390IMAGES is either a single image specification or a vector of four
2391image specifications. If it is a vector, this table lists the
2392meaning of each of the four elements:
2393
2394 Index Use when item is
2395 ----------------------------------------
2396 0 enabled and selected
2397 1 enabled and deselected
2398 2 disabled and selected
2399 3 disabled and deselected
79214ddf 2400
a933dad1 2401`:help HELP-STRING'.
79214ddf 2402
a933dad1
DL
2403Gives a help string to display for the tool bar item. This help
2404is displayed when the mouse is moved over the item.
2405
2406*** Tool-bar-related variables.
2407
2408If `auto-resize-tool-bar' is non-nil, the tool bar will automatically
2409resize to show all defined tool bar items. It will never grow larger
2410than 1/4 of the frame's size.
2411
79214ddf 2412If `auto-raise-tool-bar-buttons' is non-nil, tool bar buttons will be
a933dad1
DL
2413raised when the mouse moves over them.
2414
2415You can add extra space between tool bar items by setting
2416`tool-bar-button-margin' to a positive integer specifying a number of
2417pixels. Default is 1.
2418
2419You can change the shadow thickness of tool bar buttons by setting
2420`tool-bar-button-relief' to an integer. Default is 3.
2421
2422*** Tool-bar clicks with modifiers.
2423
2424You can bind commands to clicks with control, shift, meta etc. on
79214ddf 2425a tool bar item. If
a933dad1
DL
2426
2427 (define-key global-map [tool-bar shell]
2428 '(menu-item "Shell" shell
2429 :image (image :type xpm :file "shell.xpm")))
2430
2431is the original tool bar item definition, then
2432
2433 (define-key global-map [tool-bar S-shell] 'some-command)
2434
2435makes a binding to run `some-command' for a shifted click on the same
2436item.
2437
2438** Mode line changes.
2439
2440+++
2441*** Mouse-sensitive mode line.
2442
2443The mode line can be made mouse-sensitive by displaying strings there
2444that have a `local-map' text property. There are three ways to display
2445a string with a `local-map' property in the mode line.
2446
24471. The mode line spec contains a variable whose string value has
2448a `local-map' text property.
2449
24502. The mode line spec contains a format specifier (e.g. `%12b'), and
2451that format specifier has a `local-map' property.
2452
24533. The mode line spec contains a list containing `:eval FORM'. FORM
2454is evaluated. If the result is a string, and that string has a
2455`local-map' property.
2456
2457The same mechanism is used to determine the `face' and `help-echo'
2458properties of strings in the mode line. See `bindings.el' for an
2459example.
2460
54522c9f
GM
2461*** If a mode line element has the form `(:eval FORM)', FORM is
2462evaluated and the result is used as mode line element.
2463
a933dad1
DL
2464+++
2465*** You can suppress mode-line display by setting the buffer-local
2466variable mode-line-format to nil.
2467
2468+++
2469*** A headerline can now be displayed at the top of a window.
2470
2471This mode line's contents are controlled by the new variable
2472`header-line-format' and `default-header-line-format' which are
2473completely analogous to `mode-line-format' and
2474`default-mode-line-format'. A value of nil means don't display a top
2475line.
2476
2477The appearance of top mode lines is controlled by the face
2478`header-line'.
2479
2480The function `coordinates-in-window-p' returns `header-line' for a
2481position in the header-line.
2482
2483+++
2484** Text property `display'
2485
2486The `display' text property is used to insert images into text, and
2487also control other aspects of how text displays. The value of the
2488`display' property should be a display specification, as described
2489below, or a list or vector containing display specifications.
2490
2491*** Variable width and height spaces
2492
2493To display a space of fractional width or height, use a display
2494specification of the form `(LOCATION STRECH)'. If LOCATION is
2495`(margin left-margin)', the space is displayed in the left marginal
2496area, if it is `(margin right-margin)', it is displayed in the right
2497marginal area, and if LOCATION is `(margin nil)' the space is
2498displayed in the text. In the latter case you can also use the
2499simpler form STRETCH as property value.
2500
2501The stretch specification STRETCH itself is a list of the form `(space
2502PROPS)', where PROPS is a property list which can contain the
2503properties described below.
2504
2505The display of the fractional space replaces the display of the
2506characters having the `display' property.
2507
2508- :width WIDTH
2509
2510Specifies that the space width should be WIDTH times the normal
2511character width. WIDTH can be an integer or floating point number.
2512
2513- :relative-width FACTOR
2514
2515Specifies that the width of the stretch should be computed from the
2516first character in a group of consecutive characters that have the
2517same `display' property. The computation is done by multiplying the
2518width of that character by FACTOR.
2519
2520- :align-to HPOS
2521
2522Specifies that the space should be wide enough to reach HPOS. The
2523value HPOS is measured in units of the normal character width.
2524
2525Exactly one of the above properties should be used.
2526
2527- :height HEIGHT
2528
2529Specifies the height of the space, as HEIGHT, measured in terms of the
2530normal line height.
2531
2532- :relative-height FACTOR
2533
2534The height of the space is computed as the product of the height
2535of the text having the `display' property and FACTOR.
2536
2537- :ascent ASCENT
2538
2539Specifies that ASCENT percent of the height of the stretch should be
2540used for the ascent of the stretch, i.e. for the part above the
2541baseline. The value of ASCENT must be a non-negative number less or
2542equal to 100.
2543
2544You should not use both `:height' and `:relative-height' together.
2545
2546*** Images
2547
2548A display specification for an image has the form `(LOCATION
2549. IMAGE)', where IMAGE is an image specification. The image replaces,
2550in the display, the characters having this display specification in
2551their `display' text property. If LOCATION is `(margin left-margin)',
2552the image will be displayed in the left marginal area, if it is
2553`(margin right-margin)' it will be displayed in the right marginal
2554area, and if LOCATION is `(margin nil)' the image will be displayed in
2555the text. In the latter case you can also use the simpler form IMAGE
2556as display specification.
2557
2558*** Other display properties
2559
2560- :space-width FACTOR
2561
2562Specifies that space characters in the text having that property
2563should be displayed FACTOR times as wide as normal; FACTOR must be an
2564integer or float.
2565
2566- :height HEIGHT
2567
2568Display text having this property in a font that is smaller or larger.
2569
2570If HEIGHT is a list of the form `(+ N)', where N is an integer, that
2571means to use a font that is N steps larger. If HEIGHT is a list of
2572the form `(- N)', that means to use a font that is N steps smaller. A
2573``step'' is defined by the set of available fonts; each size for which
2574a font is available counts as a step.
2575
2576If HEIGHT is a number, that means to use a font that is HEIGHT times
2577as tall as the frame's default font.
2578
2579If HEIGHT is a symbol, it is called as a function with the current
2580height as argument. The function should return the new height to use.
2581
2582Otherwise, HEIGHT is evaluated to get the new height, with the symbol
2583`height' bound to the current specified font height.
2584
2585- :raise FACTOR
2586
2587FACTOR must be a number, specifying a multiple of the current
2588font's height. If it is positive, that means to display the characters
2589raised. If it is negative, that means to display them lower down. The
2590amount of raising or lowering is computed without taking account of the
2591`:height' subproperty.
2592
2593*** Conditional display properties
2594
2595All display specifications can be conditionalized. If a specification
2596has the form `(:when CONDITION . SPEC)', the specification SPEC
2597applies only when CONDITION yields a non-nil value when evaluated.
2598During evaluattion, point is temporarily set to the end position of
2599the text having the `display' property.
2600
2601The normal specification consisting of SPEC only is equivalent to
2602`(:when t SPEC)'.
2603
2604+++
2605** New menu separator types.
2606
2607Emacs now supports more than one menu separator type. Menu items with
2608item names consisting of dashes only (including zero dashes) are
2609treated like before. In addition, the following item names are used
2610to specify other menu separator types.
2611
2612- `--no-line' or `--space', or `--:space', or `--:noLine'
2613
2614No separator lines are drawn, but a small space is inserted where the
2615separator occurs.
2616
2617- `--single-line' or `--:singleLine'
2618
2619A single line in the menu's foreground color.
2620
2621- `--double-line' or `--:doubleLine'
2622
2623A double line in the menu's foreground color.
2624
2625- `--single-dashed-line' or `--:singleDashedLine'
2626
2627A single dashed line in the menu's foreground color.
2628
2629- `--double-dashed-line' or `--:doubleDashedLine'
2630
2631A double dashed line in the menu's foreground color.
2632
2633- `--shadow-etched-in' or `--:shadowEtchedIn'
2634
2635A single line with 3D sunken appearance. This is the the form
2636displayed for item names consisting of dashes only.
2637
2638- `--shadow-etched-out' or `--:shadowEtchedOut'
2639
2640A single line with 3D raised appearance.
2641
2642- `--shadow-etched-in-dash' or `--:shadowEtchedInDash'
2643
2644A single dashed line with 3D sunken appearance.
2645
2646- `--shadow-etched-out-dash' or `--:shadowEtchedOutDash'
2647
2648A single dashed line with 3D raise appearance.
2649
2650- `--shadow-double-etched-in' or `--:shadowDoubleEtchedIn'
2651
2652Two lines with 3D sunken appearance.
2653
2654- `--shadow-double-etched-out' or `--:shadowDoubleEtchedOut'
2655
2656Two lines with 3D raised appearance.
2657
2658- `--shadow-double-etched-in-dash' or `--:shadowDoubleEtchedInDash'
2659
2660Two dashed lines with 3D sunken appearance.
2661
2662- `--shadow-double-etched-out-dash' or `--:shadowDoubleEtchedOutDash'
2663
2664Two dashed lines with 3D raised appearance.
2665
2666Under LessTif/Motif, the last four separator types are displayed like
2667the corresponding single-line separators.
2668
2669+++
2670** New frame parameters for scroll bar colors.
2671
2672The new frame parameters `scroll-bar-foreground' and
2673`scroll-bar-background' can be used to change scroll bar colors.
2674Their value must be either a color name, a string, or nil to specify
2675that scroll bars should use a default color. For toolkit scroll bars,
2676default colors are toolkit specific. For non-toolkit scroll bars, the
2677default background is the background color of the frame, and the
2678default foreground is black.
2679
2680The X resource name of these parameters are `scrollBarForeground'
2681(class ScrollBarForeground) and `scrollBarBackground' (class
2682`ScrollBarBackground').
2683
2684Setting these parameters overrides toolkit specific X resource
2685settings for scroll bar colors.
2686
2687+++
2688** You can set `redisplay-dont-pause' to a non-nil value to prevent
2689display updates from being interrupted when input is pending.
2690
2691---
2692** Changing a window's width may now change its window start if it
2693starts on a continuation line. The new window start is computed based
2694on the window's new width, starting from the start of the continued
2695line as the start of the screen line with the minimum distance from
2696the original window start.
2697
2698---
2699** The variable `hscroll-step' and the functions
2700`hscroll-point-visible' and `hscroll-window-column' have been removed
2701now that proper horizontal scrolling is implemented.
2702
2703+++
2704** Windows can now be made fixed-width and/or fixed-height.
2705
2706A window is fixed-size if its buffer has a buffer-local variable
2707`window-size-fixed' whose value is not nil. A value of `height' makes
2708windows fixed-height, a value of `width' makes them fixed-width, any
2709other non-nil value makes them both fixed-width and fixed-height.
2710
2711The following code makes all windows displaying the current buffer
2712fixed-width and fixed-height.
2713
2714 (set (make-local-variable 'window-size-fixed) t)
2715
2716A call to enlarge-window on a window gives an error if that window is
2717fixed-width and it is tried to change the window's width, or if the
2718window is fixed-height, and it is tried to change its height. To
2719change the size of a fixed-size window, bind `window-size-fixed'
2720temporarily to nil, for example
2721
2722 (let ((window-size-fixed nil))
2723 (enlarge-window 10))
2724
79214ddf 2725Likewise, an attempt to split a fixed-height window vertically,
a933dad1 2726or a fixed-width window horizontally results in a error.
e411ce4b
EZ
2727
2728** The cursor-type frame parameter is now supported on MS-DOS
2729terminals. When Emacs starts, it by default changes the cursor shape
2730to a solid box, as it does on Unix. The `cursor-type' frame parameter
2731overrides this as it does on Unix, except that the bar cursor is
2732horizontal rather than vertical (since the MS-DOS display doesn't
2733support a vertical-bar cursor).
e33b0397
DL
2734^L
2735* Emacs 20.5 is a bug-fix release with no user-visible changes.
2736
2737** Not new, but not mentioned before:
2738M-w when Transient Mark mode is enabled disables the mark.
a933dad1
DL
2739\f
2740* Changes in Emacs 20.4
2741
2742** Init file may be called .emacs.el.
2743
2744You can now call the Emacs init file `.emacs.el'.
2745Formerly the name had to be `.emacs'. If you use the name
2746`.emacs.el', you can byte-compile the file in the usual way.
2747
2748If both `.emacs' and `.emacs.el' exist, the latter file
2749is the one that is used.
2750
2751** shell-command, and shell-command-on-region, now return
2752the exit code of the command (unless it is asynchronous).
2753Also, you can specify a place to put the error output,
2754separate from the command's regular output.
2755Interactively, the variable shell-command-default-error-buffer
2756says where to put error output; set it to a buffer name.
2757In calls from Lisp, an optional argument ERROR-BUFFER specifies
2758the buffer name.
2759
2760When you specify a non-nil error buffer (or buffer name), any error
2761output is inserted before point in that buffer, with \f\n to separate
2762it from the previous batch of error output. The error buffer is not
2763cleared, so error output from successive commands accumulates there.
2764
2765** Setting the default value of enable-multibyte-characters to nil in
2766the .emacs file, either explicitly using setq-default, or via Custom,
2767is now essentially equivalent to using --unibyte: all buffers
2768created during startup will be made unibyte after loading .emacs.
2769
2770** C-x C-f now handles the wildcards * and ? in file names. For
2771example, typing C-x C-f c*.c RET visits all the files whose names
2772match c*.c. To visit a file whose name contains * or ?, add the
2773quoting sequence /: to the beginning of the file name.
2774
2775** The M-x commands keep-lines, flush-lines and count-matches
2776now have the same feature as occur and query-replace:
2777if the pattern contains any upper case letters, then
2778they never ignore case.
2779
2780** The end-of-line format conversion feature previously mentioned
2781under `* Emacs 20.1 changes for MS-DOS and MS-Windows' actually
2782applies to all operating systems. Emacs recognizes from the contents
2783of a file what convention it uses to separate lines--newline, CRLF, or
2784just CR--and automatically converts the contents to the normal Emacs
2785convention (using newline to separate lines) for editing. This is a
2786part of the general feature of coding system conversion.
2787
2788If you subsequently save the buffer, Emacs converts the text back to
2789the same format that was used in the file before.
2790
2791You can turn off end-of-line conversion by setting the variable
2792`inhibit-eol-conversion' to non-nil, e.g. with Custom in the MULE group.
2793
2794** The character set property `prefered-coding-system' has been
2795renamed to `preferred-coding-system', for the sake of correct spelling.
2796This is a fairly internal feature, so few programs should be affected.
2797
2798** Mode-line display of end-of-line format is changed.
2799The indication of the end-of-line format of the file visited by a
2800buffer is now more explicit when that format is not the usual one for
2801your operating system. For example, the DOS-style end-of-line format
2802is displayed as "(DOS)" on Unix and GNU/Linux systems. The usual
2803end-of-line format is still displayed as a single character (colon for
2804Unix, backslash for DOS and Windows, and forward slash for the Mac).
2805
2806The values of the variables eol-mnemonic-unix, eol-mnemonic-dos,
2807eol-mnemonic-mac, and eol-mnemonic-undecided, which are strings,
2808control what is displayed in the mode line for each end-of-line
2809format. You can now customize these variables.
2810
2811** In the previous version of Emacs, tar-mode didn't work well if a
2812filename contained non-ASCII characters. Now this is fixed. Such a
2813filename is decoded by file-name-coding-system if the default value of
2814enable-multibyte-characters is non-nil.
2815
2816** The command temp-buffer-resize-mode toggles a minor mode
2817in which temporary buffers (such as help buffers) are given
2818windows just big enough to hold the whole contents.
2819
2820** If you use completion.el, you must now run the function
2821dynamic-completion-mode to enable it. Just loading the file
2822doesn't have any effect.
2823
2824** In Flyspell mode, the default is now to make just one Ispell process,
2825not one per buffer.
2826
2827** If you use iswitchb but do not call (iswitchb-default-keybindings) to
2828use the default keybindings, you will need to add the following line:
2829 (add-hook 'minibuffer-setup-hook 'iswitchb-minibuffer-setup)
2830
2831** Auto-show mode is no longer enabled just by loading auto-show.el.
2832To control it, set `auto-show-mode' via Custom or use the
2833`auto-show-mode' command.
2834
2835** Handling of X fonts' ascent/descent parameters has been changed to
2836avoid redisplay problems. As a consequence, compared with previous
2837versions the line spacing and frame size now differ with some font
2838choices, typically increasing by a pixel per line. This change
2839occurred in version 20.3 but was not documented then.
2840
2841** If you select the bar cursor style, it uses the frame's
2842cursor-color, rather than the cursor foreground pixel.
2843
2844** In multibyte mode, Rmail decodes incoming MIME messages using the
2845character set specified in the message. If you want to disable this
2846feature, set the variable rmail-decode-mime-charset to nil.
2847
2848** Not new, but not mentioned previously in NEWS: when you use #! at
2849the beginning of a file to make it executable and specify an
2850interpreter program, Emacs looks on the second line for the -*- mode
2851and variable specification, as well as on the first line.
2852
2853** Support for IBM codepage encoding of non-ASCII characters.
2854
2855The new command M-x codepage-setup creates a special coding system
2856that can be used to convert text between a specific IBM codepage and
2857one of the character sets built into Emacs which matches that
2858codepage. For example, codepage 850 corresponds to Latin-1 character
2859set, codepage 855 corresponds to Cyrillic-ISO character set, etc.
2860
2861Windows codepages 1250, 1251 and some others, where Windows deviates
2862from the corresponding ISO character set, are also supported.
2863
2864IBM box-drawing characters and other glyphs which don't have
2865equivalents in the corresponding ISO character set, are converted to
2866a character defined by dos-unsupported-char-glyph on MS-DOS, and to
2867`?' on other systems.
2868
2869IBM codepages are widely used on MS-DOS and MS-Windows, so this
2870feature is most useful on those platforms, but it can also be used on
2871Unix.
2872
2873Emacs compiled for MS-DOS automatically loads the support for the
2874current codepage when it starts.
2875
2876** Mail changes
2877
feab4fba
GM
2878*** When mail is sent using compose-mail (C-x m), and if
2879`mail-send-nonascii' is set to the new default value `mime',
2880appropriate MIME headers are added. The headers are added only if
2881non-ASCII characters are present in the body of the mail, and no other
2882MIME headers are already present. For example, the following three
2883headers are added if the coding system used in the *mail* buffer is
2884latin-1:
2885
2886 MIME-version: 1.0
2887 Content-type: text/plain; charset=iso-8859-1
2888 Content-Transfer-Encoding: 8bit
2889
a933dad1
DL
2890*** The new variable default-sendmail-coding-system specifies the
2891default way to encode outgoing mail. This has higher priority than
2892default-buffer-file-coding-system but has lower priority than
2893sendmail-coding-system and the local value of
2894buffer-file-coding-system.
2895
2896You should not set this variable manually. Instead, set
2897sendmail-coding-system to specify a fixed encoding for all outgoing
2898mail.
2899
2900*** When you try to send a message that contains non-ASCII characters,
2901if the coding system specified by those variables doesn't handle them,
2902Emacs will ask you to select a suitable coding system while showing a
2903list of possible coding systems.
2904
2905** CC Mode changes
2906
2907*** c-default-style can now take an association list that maps major
2908modes to style names. When this variable is an alist, Java mode no
2909longer hardcodes a setting to "java" style. See the variable's
2910docstring for details.
2911
2912*** It's now possible to put a list as the offset on a syntactic
2913symbol. The list is evaluated recursively until a non-nil offset is
2914found. This is useful to combine several lineup functions to act in a
2915prioritized order on a single line. However, none of the supplied
2916lineup functions use this feature currently.
2917
2918*** New syntactic symbol catch-clause, which is used on the "catch" and
2919"finally" lines in try-catch constructs in C++ and Java.
2920
2921*** New cleanup brace-catch-brace on c-cleanup-list, which does for
2922"catch" lines what brace-elseif-brace does for "else if" lines.
2923
2924*** The braces of Java anonymous inner classes are treated separately
2925from the braces of other classes in auto-newline mode. Two new
2926symbols inexpr-class-open and inexpr-class-close may be used on
2927c-hanging-braces-alist to control the automatic newlines used for
2928anonymous classes.
2929
2930*** Support for the Pike language added, along with new Pike specific
2931syntactic symbols: inlambda, lambda-intro-cont
2932
2933*** Support for Java anonymous classes via new syntactic symbol
2934inexpr-class. New syntactic symbol inexpr-statement for Pike
2935support and gcc-style statements inside expressions. New lineup
2936function c-lineup-inexpr-block.
2937
2938*** New syntactic symbol brace-entry-open which is used in brace lists
2939(i.e. static initializers) when a list entry starts with an open
2940brace. These used to be recognized as brace-list-entry's.
2941c-electric-brace also recognizes brace-entry-open braces
2942(brace-list-entry's can no longer be electrified).
2943
2944*** New command c-indent-line-or-region, not bound by default.
2945
2946*** `#' is only electric when typed in the indentation of a line.
2947
2948*** Parentheses are now electric (via the new command c-electric-paren)
2949for auto-reindenting lines when parens are typed.
2950
2951*** In "gnu" style, inline-open offset is now set to zero.
2952
2953*** Uniform handling of the inclass syntactic symbol. The indentation
2954associated with it is now always relative to the class opening brace.
2955This means that the indentation behavior has changed in some
2956circumstances, but only if you've put anything besides 0 on the
2957class-open syntactic symbol (none of the default styles do that).
2958
2959** Gnus changes.
2960
2961*** New functionality for using Gnus as an offline newsreader has been
2962added. A plethora of new commands and modes have been added. See the
2963Gnus manual for the full story.
2964
2965*** The nndraft backend has returned, but works differently than
2966before. All Message buffers are now also articles in the nndraft
2967group, which is created automatically.
2968
2969*** `gnus-alter-header-function' can now be used to alter header
2970values.
2971
2972*** `gnus-summary-goto-article' now accept Message-ID's.
2973
2974*** A new Message command for deleting text in the body of a message
2975outside the region: `C-c C-v'.
2976
2977*** You can now post to component group in nnvirtual groups with
2978`C-u C-c C-c'.
2979
2980*** `nntp-rlogin-program' -- new variable to ease customization.
2981
2982*** `C-u C-c C-c' in `gnus-article-edit-mode' will now inhibit
2983re-highlighting of the article buffer.
2984
2985*** New element in `gnus-boring-article-headers' -- `long-to'.
2986
2987*** `M-i' symbolic prefix command. See the section "Symbolic
2988Prefixes" in the Gnus manual for details.
2989
2990*** `L' and `I' in the summary buffer now take the symbolic prefix
2991`a' to add the score rule to the "all.SCORE" file.
2992
2993*** `gnus-simplify-subject-functions' variable to allow greater
2994control over simplification.
2995
2996*** `A T' -- new command for fetching the current thread.
2997
2998*** `/ T' -- new command for including the current thread in the
2999limit.
3000
3001*** `M-RET' is a new Message command for breaking cited text.
3002
3003*** \\1-expressions are now valid in `nnmail-split-methods'.
3004
79214ddf 3005*** The `custom-face-lookup' function has been removed.
a933dad1
DL
3006If you used this function in your initialization files, you must
3007rewrite them to use `face-spec-set' instead.
3008
3009*** Cancelling now uses the current select method. Symbolic prefix
3010`a' forces normal posting method.
3011
3012*** New command to translate M******** sm*rtq**t*s into proper text
3013-- `W d'.
3014
3015*** For easier debugging of nntp, you can set `nntp-record-commands'
3016to a non-nil value.
3017
3018*** nntp now uses ~/.authinfo, a .netrc-like file, for controlling
3019where and how to send AUTHINFO to NNTP servers.
3020
3021*** A command for editing group parameters from the summary buffer
3022has been added.
3023
3024*** A history of where mails have been split is available.
3025
3026*** A new article date command has been added -- `article-date-iso8601'.
3027
3028*** Subjects can be simplified when threading by setting
3029`gnus-score-thread-simplify'.
3030
3031*** A new function for citing in Message has been added --
3032`message-cite-original-without-signature'.
3033
3034*** `article-strip-all-blank-lines' -- new article command.
3035
3036*** A new Message command to kill to the end of the article has
3037been added.
3038
3039*** A minimum adaptive score can be specified by using the
3040`gnus-adaptive-word-minimum' variable.
3041
3042*** The "lapsed date" article header can be kept continually
3043updated by the `gnus-start-date-timer' command.
3044
3045*** Web listserv archives can be read with the nnlistserv backend.
3046
3047*** Old dejanews archives can now be read by nnweb.
3048
3049*** `gnus-posting-styles' has been re-activated.
3050
3051** Changes to TeX and LaTeX mode
3052
3053*** The new variable `tex-start-options-string' can be used to give
3054options for the TeX run. The default value causes TeX to run in
3055nonstopmode. For an interactive TeX run set it to nil or "".
3056
3057*** The command `tex-feed-input' sends input to the Tex Shell. In a
3058TeX buffer it is bound to the keys C-RET, C-c RET, and C-c C-m (some
3059of these keys may not work on all systems). For instance, if you run
3060TeX interactively and if the TeX run stops because of an error, you
3061can continue it without leaving the TeX buffer by typing C-RET.
3062
3063*** The Tex Shell Buffer is now in `compilation-shell-minor-mode'.
3064All error-parsing commands of the Compilation major mode are available
3065but bound to keys that don't collide with the shell. Thus you can use
3066the Tex Shell for command line executions like a usual shell.
3067
3068*** The commands `tex-validate-region' and `tex-validate-buffer' check
3069the matching of braces and $'s. The errors are listed in a *Occur*
3070buffer and you can use C-c C-c or mouse-2 to go to a particular
3071mismatch.
3072
3073** Changes to RefTeX mode
3074
3075*** The table of contents buffer can now also display labels and
3076file boundaries in addition to sections. Use `l', `i', and `c' keys.
3077
3078*** Labels derived from context (the section heading) are now
3079lowercase by default. To make the label legal in LaTeX, latin-1
3080characters will lose their accent. All Mule characters will be
3081removed from the label.
3082
3083*** The automatic display of cross reference information can also use
3084a window instead of the echo area. See variable `reftex-auto-view-crossref'.
3085
3086*** kpsewhich can be used by RefTeX to find TeX and BibTeX files. See the
3087customization group `reftex-finding-files'.
3088
3089*** The option `reftex-bibfile-ignore-list' has been renamed to
3090`reftex-bibfile-ignore-regexps' and indeed can be fed with regular
79214ddf 3091expressions.
a933dad1
DL
3092
3093*** Multiple Selection buffers are now hidden buffers.
3094
3095** New/deleted modes and packages
3096
3097*** The package snmp-mode.el provides major modes for editing SNMP and
3098SNMPv2 MIBs. It has entries on `auto-mode-alist'.
3099
3100*** The package sql.el provides a major mode, M-x sql-mode, for
3101editing SQL files, and M-x sql-interactive-mode for interacting with
3102SQL interpreters. It has an entry on `auto-mode-alist'.
3103
3104*** M-x highlight-changes-mode provides a minor mode displaying buffer
3105changes with a special face.
3106
3107*** ispell4.el has been deleted. It got in the way of ispell.el and
3108this was hard to fix reliably. It has long been obsolete -- use
3109Ispell 3.1 and ispell.el.
3110\f
3111* MS-DOS changes in Emacs 20.4
3112
3113** Emacs compiled for MS-DOS now supports MULE features better.
3114This includes support for display of all ISO 8859-N character sets,
3115conversion to and from IBM codepage encoding of non-ASCII characters,
3116and automatic setup of the MULE environment at startup. For details,
3117check out the section `MS-DOS and MULE' in the manual.
3118
3119The MS-DOS installation procedure automatically configures and builds
3120Emacs with input method support if it finds an unpacked Leim
3121distribution when the config.bat script is run.
3122
3123** Formerly, the value of lpr-command did not affect printing on
3124MS-DOS unless print-region-function was set to nil, but now it
3125controls whether an external program is invoked or output is written
3126directly to a printer port. Similarly, in the previous version of
3127Emacs, the value of ps-lpr-command did not affect PostScript printing
3128on MS-DOS unless ps-printer-name was set to something other than a
3129string (eg. t or `pipe'), but now it controls whether an external
3130program is used. (These changes were made so that configuration of
3131printing variables would be almost identical across all platforms.)
3132
3133** In the previous version of Emacs, PostScript and non-PostScript
3134output was piped to external programs, but because most print programs
3135available for MS-DOS and MS-Windows cannot read data from their standard
3136input, on those systems the data to be output is now written to a
3137temporary file whose name is passed as the last argument to the external
3138program.
3139
3140An exception is made for `print', a standard program on Windows NT,
3141and `nprint', a standard program on Novell Netware. For both of these
3142programs, the command line is constructed in the appropriate syntax
3143automatically, using only the value of printer-name or ps-printer-name
3144as appropriate--the value of the relevant `-switches' variable is
3145ignored, as both programs have no useful switches.
3146
3147** The value of the variable dos-printer (cf. dos-ps-printer), if it has
3148a value, overrides the value of printer-name (cf. ps-printer-name), on
3149MS-DOS and MS-Windows only. This has been true since version 20.3, but
3150was not documented clearly before.
3151
3152** All the Emacs games now work on MS-DOS terminals.
3153This includes Tetris and Snake.
3154\f
3155* Lisp changes in Emacs 20.4
3156
3157** New functions line-beginning-position and line-end-position
3158return the position of the beginning or end of the current line.
3159They both accept an optional argument, which has the same
3160meaning as the argument to beginning-of-line or end-of-line.
3161
3162** find-file and allied functions now have an optional argument
3163WILDCARD. If this is non-nil, they do wildcard processing,
3164and visit all files that match the wildcard pattern.
3165
3166** Changes in the file-attributes function.
3167
3168*** The file size returned by file-attributes may be an integer or a float.
3169It is an integer if the size fits in a Lisp integer, float otherwise.
3170
3171*** The inode number returned by file-attributes may be an integer (if
3172the number fits in a Lisp integer) or a cons cell containing two
3173integers.
3174
3175** The new function directory-files-and-attributes returns a list of
3176files in a directory and their attributes. It accepts the same
3177arguments as directory-files and has similar semantics, except that
3178file names and attributes are returned.
3179
3180** The new function file-attributes-lessp is a helper function for
3181sorting the list generated by directory-files-and-attributes. It
3182accepts two arguments, each a list of a file name and its atttributes.
3183It compares the file names of each according to string-lessp and
3184returns the result.
3185
3186** The new function file-expand-wildcards expands a wildcard-pattern
3187to produce a list of existing files that match the pattern.
3188
3189** New functions for base64 conversion:
3190
3191The function base64-encode-region converts a part of the buffer
3192into the base64 code used in MIME. base64-decode-region
3193performs the opposite conversion. Line-breaking is supported
3194optionally.
3195
3196Functions base64-encode-string and base64-decode-string do a similar
3197job on the text in a string. They return the value as a new string.
3198
3199**
3200The new function process-running-child-p
3201will tell you if a subprocess has given control of its
3202terminal to its own child process.
3203
3204** interrupt-process and such functions have a new feature:
3205when the second argument is `lambda', they send a signal
3206to the running child of the subshell, if any, but if the shell
3207itself owns its terminal, no signal is sent.
3208
3209** There are new widget types `plist' and `alist' which can
3210be used for customizing variables whose values are plists or alists.
3211
3212** easymenu.el Now understands `:key-sequence' and `:style button'.
3213:included is an alias for :visible.
3214
3215easy-menu-add-item now understands the values returned by
3216easy-menu-remove-item and easy-menu-item-present-p. This can be used
3217to move or copy menu entries.
3218
3219** Multibyte editing changes
3220
3221*** The definitions of sref and char-bytes are changed. Now, sref is
3222an alias of aref and char-bytes always returns 1. This change is to
3223make some Emacs Lisp code which works on 20.2 and earlier also
3224work on the latest Emacs. Such code uses a combination of sref and
3225char-bytes in a loop typically as below:
3226 (setq char (sref str idx)
3227 idx (+ idx (char-bytes idx)))
3228The byte-compiler now warns that this is obsolete.
3229
3230If you want to know how many bytes a specific multibyte character
3231(say, CH) occupies in a multibyte buffer, use this code:
3232 (charset-bytes (char-charset ch))
3233
3234*** In multibyte mode, when you narrow a buffer to some region, and the
3235region is preceded or followed by non-ASCII codes, inserting or
3236deleting at the head or the end of the region may signal this error:
3237
3238 Byte combining across boundary of accessible buffer text inhibitted
3239
3240This is to avoid some bytes being combined together into a character
3241across the boundary.
3242
3243*** The functions find-charset-region and find-charset-string include
3244`unknown' in the returned list in the following cases:
3245 o The current buffer or the target string is unibyte and
3246 contains 8-bit characters.
3247 o The current buffer or the target string is multibyte and
3248 contains invalid characters.
3249
3250*** The functions decode-coding-region and encode-coding-region remove
3251text properties of the target region. Ideally, they should correctly
3252preserve text properties, but for the moment, it's hard. Removing
3253text properties is better than preserving them in a less-than-correct
3254way.
3255
3256*** prefer-coding-system sets EOL conversion of default coding systems.
3257If the argument to prefer-coding-system specifies a certain type of
3258end of line conversion, the default coding systems set by
3259prefer-coding-system will specify that conversion type for end of line.
3260
3261*** The new function thai-compose-string can be used to properly
3262compose Thai characters in a string.
3263
3264** The primitive `define-prefix-command' now takes an optional third
3265argument NAME, which should be a string. It supplies the menu name
3266for the created keymap. Keymaps created in order to be displayed as
3267menus should always use the third argument.
3268
3269** The meanings of optional second arguments for read-char,
3270read-event, and read-char-exclusive are flipped. Now the second
3271arguments are INHERIT-INPUT-METHOD. These functions use the current
3272input method (if any) if and only if INHERIT-INPUT-METHOD is non-nil.
3273
3274** The new function clear-this-command-keys empties out the contents
3275of the vector that (this-command-keys) returns. This is useful in
3276programs that read passwords, to prevent the passwords from echoing
3277inadvertently as part of the next command in certain cases.
3278
3279** The new macro `with-temp-message' displays a temporary message in
3280the echo area, while executing some Lisp code. Like `progn', it
3281returns the value of the last form, but it also restores the previous
3282echo area contents.
3283
3284 (with-temp-message MESSAGE &rest BODY)
3285
3286** The function `require' now takes an optional third argument
3287NOERROR. If it is non-nil, then there is no error if the
3288requested feature cannot be loaded.
3289
3290** In the function modify-face, an argument of (nil) for the
3291foreground color, background color or stipple pattern
79214ddf 3292means to clear out that attribute.
a933dad1
DL
3293
3294** The `outer-window-id' frame property of an X frame
3295gives the window number of the outermost X window for the frame.
3296
3297** Temporary buffers made with with-output-to-temp-buffer are now
3298read-only by default, and normally use the major mode Help mode
3299unless you put them in some other non-Fundamental mode before the
3300end of with-output-to-temp-buffer.
3301
3302** The new functions gap-position and gap-size return information on
3303the gap of the current buffer.
3304
3305** The new functions position-bytes and byte-to-position provide a way
3306to convert between character positions and byte positions in the
3307current buffer.
3308
3309** vc.el defines two new macros, `edit-vc-file' and `with-vc-file', to
3310facilitate working with version-controlled files from Lisp programs.
3311These macros check out a given file automatically if needed, and check
3312it back in after any modifications have been made.
3313\f
3314* Installation Changes in Emacs 20.3
3315
3316** The default value of load-path now includes most subdirectories of
3317the site-specific directories /usr/local/share/emacs/site-lisp and
3318/usr/local/share/emacs/VERSION/site-lisp, in addition to those
3319directories themselves. Both immediate subdirectories and
3320subdirectories multiple levels down are added to load-path.
3321
3322Not all subdirectories are included, though. Subdirectories whose
3323names do not start with a letter or digit are excluded.
3324Subdirectories named RCS or CVS are excluded. Also, a subdirectory
3325which contains a file named `.nosearch' is excluded. You can use
3326these methods to prevent certain subdirectories from being searched.
3327
3328Emacs finds these subdirectories and adds them to load-path when it
3329starts up. While it would be cleaner to find the subdirectories each
3330time Emacs loads a file, that would be much slower.
3331
3332This feature is an incompatible change. If you have stored some Emacs
3333Lisp files in a subdirectory of the site-lisp directory specifically
3334to prevent them from being used, you will need to rename the
3335subdirectory to start with a non-alphanumeric character, or create a
3336`.nosearch' file in it, in order to continue to achieve the desired
3337results.
3338
3339** Emacs no longer includes an old version of the C preprocessor from
3340GCC. This was formerly used to help compile Emacs with C compilers
3341that had limits on the significant length of an identifier, but in
3342fact we stopped supporting such compilers some time ago.
3343\f
3344* Changes in Emacs 20.3
3345
3346** The new command C-x z (repeat) repeats the previous command
3347including its argument. If you repeat the z afterward,
3348it repeats the command additional times; thus, you can
3349perform many repetitions with one keystroke per repetition.
3350
3351** Emacs now supports "selective undo" which undoes only within a
3352specified region. To do this, set point and mark around the desired
3353region and type C-u C-x u (or C-u C-_). You can then continue undoing
3354further, within the same region, by repeating the ordinary undo
3355command C-x u or C-_. This will keep undoing changes that were made
3356within the region you originally specified, until either all of them
3357are undone, or it encounters a change which crosses the edge of that
3358region.
3359
3360In Transient Mark mode, undoing when a region is active requests
3361selective undo.
3362
3363** If you specify --unibyte when starting Emacs, then all buffers are
3364unibyte, except when a Lisp program specifically creates a multibyte
3365buffer. Setting the environment variable EMACS_UNIBYTE has the same
3366effect. The --no-unibyte option overrides EMACS_UNIBYTE and directs
3367Emacs to run normally in multibyte mode.
3368
3369The option --unibyte does not affect the reading of Emacs Lisp files,
3370though. If you want a Lisp file to be read in unibyte mode, use
3371-*-unibyte: t;-*- on its first line. That will force Emacs to
3372load that file in unibyte mode, regardless of how Emacs was started.
3373
3374** toggle-enable-multibyte-characters no longer has a key binding and
3375no longer appears in the menu bar. We've realized that changing the
3376enable-multibyte-characters variable in an existing buffer is
3377something that most users not do.
3378
3379** You can specify a coding system to use for the next cut or paste
3380operations through the window system with the command C-x RET X.
3381The coding system can make a difference for communication with other
3382applications.
3383
3384C-x RET x specifies a coding system for all subsequent cutting and
3385pasting operations.
3386
3387** You can specify the printer to use for commands that do printing by
3388setting the variable `printer-name'. Just what a printer name looks
3389like depends on your operating system. You can specify a different
3390printer for the Postscript printing commands by setting
3391`ps-printer-name'.
3392
3393** Emacs now supports on-the-fly spell checking by the means of a
3394minor mode. It is called M-x flyspell-mode. You don't have to remember
3395any other special commands to use it, and you will hardly notice it
3396except when you make a spelling error. Flyspell works by highlighting
3397incorrect words as soon as they are completed or as soon as the cursor
3398hits a new word.
3399
3400Flyspell mode works with whichever dictionary you have selected for
3401Ispell in Emacs. In TeX mode, it understands TeX syntax so as not
3402to be confused by TeX commands.
3403
3404You can correct a misspelled word by editing it into something
3405correct. You can also correct it, or accept it as correct, by
3406clicking on the word with Mouse-2; that gives you a pop-up menu
3407of various alternative replacements and actions.
3408
3409Flyspell mode also proposes "automatic" corrections. M-TAB replaces
3410the current misspelled word with a possible correction. If several
3411corrections are made possible, M-TAB cycles through them in
3412alphabetical order, or in order of decreasing likelihood if
3413flyspell-sort-corrections is nil.
3414
3415Flyspell mode also flags an error when a word is repeated, if
3416flyspell-mark-duplications-flag is non-nil.
3417
3418** Changes in input method usage.
3419
3420Now you can use arrow keys (right, left, down, up) for selecting among
3421the alternatives just the same way as you do by C-f, C-b, C-n, and C-p
3422respectively.
3423
3424You can use the ENTER key to accept the current conversion.
3425
3426If you type TAB to display a list of alternatives, you can select one
3427of the alternatives with Mouse-2.
3428
3429The meaning of the variable `input-method-verbose-flag' is changed so
3430that you can set it to t, nil, `default', or `complex-only'.
3431
3432 If the value is nil, extra guidance is never given.
3433
3434 If the value is t, extra guidance is always given.
3435
3436 If the value is `complex-only', extra guidance is always given only
3437 when you are using complex input methods such as chinese-py.
3438
3439 If the value is `default' (this is the default), extra guidance is
79214ddf 3440 given in the following case:
a933dad1
DL
3441 o When you are using a complex input method.
3442 o When you are using a simple input method but not in the minibuffer.
3443
3444If you are using Emacs through a very slow line, setting
3445input-method-verbose-flag to nil or to complex-only is a good choice,
3446and if you are using an input method you are not familiar with,
3447setting it to t is helpful.
3448
3449The old command select-input-method is now called set-input-method.
3450
3451In the language environment "Korean", you can use the following
3452keys:
3453 Shift-SPC toggle-korean-input-method
3454 C-F9 quail-hangul-switch-symbol-ksc
3455 F9 quail-hangul-switch-hanja
3456These key bindings are canceled when you switch to another language
3457environment.
3458
3459** The minibuffer history of file names now records the specified file
3460names, not the entire minibuffer input. For example, if the
3461minibuffer starts out with /usr/foo/, you might type in /etc/passwd to
3462get
3463
3464 /usr/foo//etc/passwd
3465
3466which stands for the file /etc/passwd.
3467
3468Formerly, this used to put /usr/foo//etc/passwd in the history list.
3469Now this puts just /etc/passwd in the history list.
3470
3471** If you are root, Emacs sets backup-by-copying-when-mismatch to t
3472at startup, so that saving a file will be sure to preserve
3473its owner and group.
3474
3475** find-func.el can now also find the place of definition of Emacs
3476Lisp variables in user-loaded libraries.
3477
3478** C-x r t (string-rectangle) now deletes the existing rectangle
3479contents before inserting the specified string on each line.
3480
3481** There is a new command delete-whitespace-rectangle
3482which deletes whitespace starting from a particular column
3483in all the lines on a rectangle. The column is specified
3484by the left edge of the rectangle.
3485
3486** You can now store a number into a register with C-u NUMBER C-x r n REG,
3487increment it by INC with C-u INC C-x r + REG (to increment by one, omit
3488C-u INC), and insert it in the buffer with C-x r g REG. This is useful
3489for writing keyboard macros.
3490
3491** The new command M-x speedbar displays a frame in which directories,
3492files, and tags can be displayed, manipulated, and jumped to. The
3493frame defaults to 20 characters in width, and is the same height as
3494the frame that it was started from. Some major modes define
3495additional commands for the speedbar, including Rmail, GUD/GDB, and
3496info.
3497
3498** query-replace-regexp is now bound to C-M-%.
3499
3500** In Transient Mark mode, when the region is active, M-x
3501query-replace and the other replace commands now operate on the region
3502contents only.
3503
3504** M-x write-region, when used interactively, now asks for
3505confirmation before overwriting an existing file. When you call
3506the function from a Lisp program, a new optional argument CONFIRM
3507says whether to ask for confirmation in this case.
3508
3509** If you use find-file-literally and the file is already visited
3510non-literally, the command asks you whether to revisit the file
3511literally. If you say no, it signals an error.
3512
3513** Major modes defined with the "derived mode" feature
3514now use the proper name for the mode hook: WHATEVER-mode-hook.
3515Formerly they used the name WHATEVER-mode-hooks, but that is
3516inconsistent with Emacs conventions.
3517
3518** shell-command-on-region (and shell-command) reports success or
3519failure if the command produces no output.
3520
3521** Set focus-follows-mouse to nil if your window system or window
3522manager does not transfer focus to another window when you just move
3523the mouse.
3524
3525** mouse-menu-buffer-maxlen has been renamed to
3526mouse-buffer-menu-maxlen to be consistent with the other related
3527function and variable names.
3528
3529** The new variable auto-coding-alist specifies coding systems for
3530reading specific files. This has higher priority than
3531file-coding-system-alist.
3532
3533** If you set the variable unibyte-display-via-language-environment to
3534t, then Emacs displays non-ASCII characters are displayed by
3535converting them to the equivalent multibyte characters according to
3536the current language environment. As a result, they are displayed
3537according to the current fontset.
3538
3539** C-q's handling of codes in the range 0200 through 0377 is changed.
3540
3541The codes in the range 0200 through 0237 are inserted as one byte of
3542that code regardless of the values of nonascii-translation-table and
3543nonascii-insert-offset.
3544
3545For the codes in the range 0240 through 0377, if
3546enable-multibyte-characters is non-nil and nonascii-translation-table
3547nor nonascii-insert-offset can't convert them to valid multibyte
3548characters, they are converted to Latin-1 characters.
3549
3550** If you try to find a file that is not read-accessible, you now get
3551an error, rather than an empty buffer and a warning.
3552
3553** In the minibuffer history commands M-r and M-s, an upper case
3554letter in the regular expression forces case-sensitive search.
3555
3556** In the *Help* buffer, cross-references to commands and variables
3557are inferred and hyperlinked. Use C-h m in Help mode for the relevant
3558command keys.
3559
3560** M-x apropos-command, with a prefix argument, no longer looks for
3561user option variables--instead it looks for noninteractive functions.
3562
3563Meanwhile, the command apropos-variable normally searches for
3564user option variables; with a prefix argument, it looks at
3565all variables that have documentation.
3566
3567** When you type a long line in the minibuffer, and the minibuffer
3568shows just one line, automatically scrolling works in a special way
3569that shows you overlap with the previous line of text. The variable
3570minibuffer-scroll-overlap controls how many characters of overlap
3571it should show; the default is 20.
3572
3573Meanwhile, Resize Minibuffer mode is still available; in that mode,
3574the minibuffer grows taller (up to a point) as needed to show the whole
3575of your input.
3576
3577** The new command M-x customize-changed-options lets you customize
3578all the options whose meanings or default values have changed in
3579recent Emacs versions. You specify a previous Emacs version number as
3580argument, and the command creates a customization buffer showing all
3581the customizable options which were changed since that version.
3582Newly added options are included as well.
3583
3584If you don't specify a particular version number argument,
3585then the customization buffer shows all the customizable options
3586for which Emacs versions of changes are recorded.
3587
3588This function is also bound to the Changed Options entry in the
3589Customize menu.
3590
3591** When you run M-x grep with a prefix argument, it figures out
3592the tag around point and puts that into the default grep command.
3593
3594** The new command M-* (pop-tag-mark) pops back through a history of
3595buffer positions from which M-. or other tag-finding commands were
3596invoked.
3597
3598** The new variable comment-padding specifies the number of spaces
3599that `comment-region' will insert before the actual text of the comment.
3600The default is 1.
3601
3602** In Fortran mode the characters `.', `_' and `$' now have symbol
3603syntax, not word syntax. Fortran mode now supports `imenu' and has
3604new commands fortran-join-line (M-^) and fortran-narrow-to-subprogram
3605(C-x n d). M-q can be used to fill a statement or comment block
3606sensibly.
3607
3608** GUD now supports jdb, the Java debugger, and pdb, the Python debugger.
3609
3610** If you set the variable add-log-keep-changes-together to a non-nil
3611value, the command `C-x 4 a' will automatically notice when you make
3612two entries in one day for one file, and combine them.
3613
3614** You can use the command M-x diary-mail-entries to mail yourself a
3615reminder about upcoming diary entries. See the documentation string
3616for a sample shell script for calling this function automatically
3617every night.
3618
3619** All you need to do, to enable use of the Desktop package, is to set
3620the variable desktop-enable to t with Custom.
3621
3622** There is no need to do anything special, now, to enable Gnus to
3623read and post multi-lingual articles.
3624
3625** Outline mode has now support for showing hidden outlines when
3626doing an isearch. In order for this to happen search-invisible should
3627be set to open (the default). If an isearch match is inside a hidden
3628outline the outline is made visible. If you continue pressing C-s and
3629the match moves outside the formerly invisible outline, the outline is
79214ddf 3630made invisible again.
a933dad1
DL
3631
3632** Mail reading and sending changes
3633
3634*** The Rmail e command now switches to displaying the whole header of
3635the message before it lets you edit the message. This is so that any
3636changes you make in the header will not be lost if you subsequently
3637toggle.
3638
3639*** The w command in Rmail, which writes the message body into a file,
3640now works in the summary buffer as well. (The command to delete the
3641summary buffer is now Q.) The default file name for the w command, if
3642the message has no subject, is stored in the variable
3643rmail-default-body-file.
3644
3645*** Most of the commands and modes that operate on mail and netnews no
3646longer depend on the value of mail-header-separator. Instead, they
3647handle whatever separator the buffer happens to use.
3648
3649*** If you set mail-signature to a value which is not t, nil, or a string,
3650it should be an expression. When you send a message, this expression
3651is evaluated to insert the signature.
3652
3653*** The new Lisp library feedmail.el (version 8) enhances processing of
3654outbound email messages. It works in coordination with other email
3655handling packages (e.g., rmail, VM, gnus) and is responsible for
3656putting final touches on messages and actually submitting them for
3657transmission. Users of the emacs program "fakemail" might be
3658especially interested in trying feedmail.
3659
3660feedmail is not enabled by default. See comments at the top of
3661feedmail.el for set-up instructions. Among the bigger features
3662provided by feedmail are:
3663
3664**** you can park outgoing messages into a disk-based queue and
3665stimulate sending some or all of them later (handy for laptop users);
3666there is also a queue for draft messages
3667
3668**** you can get one last look at the prepped outbound message and
3669be prompted for confirmation
3670
3671**** does smart filling of address headers
3672
3673**** can generate a MESSAGE-ID: line and a DATE: line; the date can be
3674the time the message was written or the time it is being sent; this
3675can make FCC copies more closely resemble copies that recipients get
3676
3677**** you can specify an arbitrary function for actually transmitting
3678the message; included in feedmail are interfaces for /bin/[r]mail,
3679/usr/lib/sendmail, and elisp smtpmail; it's easy to write a new
3680function for something else (10-20 lines of elisp)
3681
3682** Dired changes
3683
3684*** The Dired function dired-do-toggle, which toggles marked and unmarked
3685files, is now bound to "t" instead of "T".
3686
3687*** dired-at-point has been added to ffap.el. It allows one to easily
3688run Dired on the directory name at point.
3689
3690*** Dired has a new command: %g. It searches the contents of
3691files in the directory and marks each file that contains a match
3692for a specified regexp.
3693
3694** VC Changes
3695
3696*** New option vc-ignore-vc-files lets you turn off version control
3697conveniently.
3698
3699*** VC Dired has been completely rewritten. It is now much
3700faster, especially for CVS, and works very similar to ordinary
3701Dired.
3702
3703VC Dired is invoked by typing C-x v d and entering the name of the
3704directory to display. By default, VC Dired gives you a recursive
3705listing of all files at or below the given directory which are
3706currently locked (for CVS, all files not up-to-date are shown).
3707
3708You can change the listing format by setting vc-dired-recurse to nil,
3709then it shows only the given directory, and you may also set
3710vc-dired-terse-display to nil, then it shows all files under version
3711control plus the names of any subdirectories, so that you can type `i'
3712on such lines to insert them manually, as in ordinary Dired.
3713
3714All Dired commands operate normally in VC Dired, except for `v', which
3715is redefined as the version control prefix. That means you may type
3716`v l', `v =' etc. to invoke `vc-print-log', `vc-diff' and the like on
3717the file named in the current Dired buffer line. `v v' invokes
3718`vc-next-action' on this file, or on all files currently marked.
3719
3720The new command `v t' (vc-dired-toggle-terse-mode) allows you to
3721toggle between terse display (only locked files) and full display (all
79214ddf 3722VC files plus subdirectories). There is also a special command,
a933dad1
DL
3723`* l', to mark all files currently locked.
3724
3725Giving a prefix argument to C-x v d now does the same thing as in
3726ordinary Dired: it allows you to supply additional options for the ls
3727command in the minibuffer, to fine-tune VC Dired's output.
3728
3729*** Under CVS, if you merge changes from the repository into a working
3730file, and CVS detects conflicts, VC now offers to start an ediff
3731session to resolve them.
3732
3733Alternatively, you can use the new command `vc-resolve-conflicts' to
3734resolve conflicts in a file at any time. It works in any buffer that
3735contains conflict markers as generated by rcsmerge (which is what CVS
3736uses as well).
3737
3738*** You can now transfer changes between branches, using the new
3739command vc-merge (C-x v m). It is implemented for RCS and CVS. When
3740you invoke it in a buffer under version-control, you can specify
3741either an entire branch or a pair of versions, and the changes on that
3742branch or between the two versions are merged into the working file.
3743If this results in any conflicts, they may be resolved interactively,
3744using ediff.
3745
3746** Changes in Font Lock
3747
3748*** The face and variable previously known as font-lock-reference-face
3749are now called font-lock-constant-face to better reflect their typical
3750use for highlighting constants and labels. (Its face properties are
3751unchanged.) The variable font-lock-reference-face remains for now for
3752compatibility reasons, but its value is font-lock-constant-face.
3753
3754** Frame name display changes
3755
3756*** The command set-frame-name lets you set the name of the current
3757frame. You can use the new command select-frame-by-name to select and
3758raise a frame; this is mostly useful on character-only terminals, or
3759when many frames are invisible or iconified.
3760
3761*** On character-only terminal (not a window system), changing the
3762frame name is now reflected on the mode line and in the Buffers/Frames
3763menu.
3764
3765** Comint (subshell) changes
3766
3767*** In Comint modes, the commands to kill, stop or interrupt a
3768subjob now also kill pending input. This is for compatibility
3769with ordinary shells, where the signal characters do this.
3770
3771*** There are new commands in Comint mode.
3772
3773C-c C-x fetches the "next" line from the input history;
3774that is, the line after the last line you got.
3775You can use this command to fetch successive lines, one by one.
3776
3777C-c SPC accumulates lines of input. More precisely, it arranges to
3778send the current line together with the following line, when you send
3779the following line.
3780
3781C-c C-a if repeated twice consecutively now moves to the process mark,
3782which separates the pending input from the subprocess output and the
3783previously sent input.
3784
3785C-c M-r now runs comint-previous-matching-input-from-input;
3786it searches for a previous command, using the current pending input
3787as the search string.
3788
3789*** New option compilation-scroll-output can be set to scroll
3790automatically in compilation-mode windows.
3791
3792** C mode changes
3793
3794*** Multiline macros are now handled, both as they affect indentation,
3795and as recognized syntax. New syntactic symbol cpp-macro-cont is
3796assigned to second and subsequent lines of a multiline macro
79214ddf 3797definition.
a933dad1
DL
3798
3799*** A new style "user" which captures all non-hook-ified
3800(i.e. top-level) .emacs file variable settings and customizations.
3801Style "cc-mode" is an alias for "user" and is deprecated. "gnu"
3802style is still the default however.
3803
3804*** "java" style now conforms to Sun's JDK coding style.
3805
3806*** There are new commands c-beginning-of-defun, c-end-of-defun which
3807are alternatives which you could bind to C-M-a and C-M-e if you prefer
3808them. They do not have key bindings by default.
3809
3810*** New and improved implementations of M-a (c-beginning-of-statement)
3811and M-e (c-end-of-statement).
3812
3813*** C++ namespace blocks are supported, with new syntactic symbols
3814namespace-open, namespace-close, and innamespace.
3815
3816*** File local variable settings of c-file-style and c-file-offsets
3817makes the style variables local to that buffer only.
3818
3819*** New indentation functions c-lineup-close-paren,
3820c-indent-one-line-block, c-lineup-dont-change.
3821
3822*** Improvements (hopefully!) to the way CC Mode is loaded. You
3823should now be able to do a (require 'cc-mode) to get the entire
3824package loaded properly for customization in your .emacs file. A new
3825variable c-initialize-on-load controls this and is t by default.
3826
3827** Changes to hippie-expand.
3828
79214ddf 3829*** New customization variable `hippie-expand-dabbrev-skip-space'. If
a933dad1
DL
3830non-nil, trailing spaces may be included in the abbreviation to search for,
3831which then gives the same behavior as the original `dabbrev-expand'.
3832
3833*** New customization variable `hippie-expand-dabbrev-as-symbol'. If
3834non-nil, characters of syntax '_' is considered part of the word when
3835expanding dynamically.
3836
3837*** New customization variable `hippie-expand-no-restriction'. If
3838non-nil, narrowed buffers are widened before they are searched.
3839
3840*** New customization variable `hippie-expand-only-buffers'. If
3841non-empty, buffers searched are restricted to the types specified in
3842this list. Useful for example when constructing new special-purpose
3843expansion functions with `make-hippie-expand-function'.
3844
3845*** Text properties of the expansion are no longer copied.
3846
3847** Changes in BibTeX mode.
3848
3849*** Any titleword matching a regexp in the new variable
3850bibtex-autokey-titleword-ignore (case sensitive) is ignored during
3851automatic key generation. This replaces variable
3852bibtex-autokey-titleword-first-ignore, which only checked for matches
3853against the first word in the title.
3854
3855*** Autokey generation now uses all words from the title, not just
3856capitalized words. To avoid conflicts with existing customizations,
3857bibtex-autokey-titleword-ignore is set up such that words starting with
79214ddf 3858lowerkey characters will still be ignored. Thus, if you want to use
a933dad1 3859lowercase words from the title, you will have to overwrite the
79214ddf 3860bibtex-autokey-titleword-ignore standard setting.
a933dad1
DL
3861
3862*** Case conversion of names and title words for automatic key
3863generation is more flexible. Variable bibtex-autokey-preserve-case is
3864replaced by bibtex-autokey-titleword-case-convert and
3865bibtex-autokey-name-case-convert.
3866
3867** Changes in vcursor.el.
3868
3869*** Support for character terminals is available: there is a new keymap
3870and the vcursor will appear as an arrow between buffer text. A
3871variable `vcursor-interpret-input' allows input from the vcursor to be
3872entered exactly as if typed. Numerous functions, including
3873`vcursor-compare-windows', have been rewritten to improve consistency
3874in the selection of windows and corresponding keymaps.
3875
3876*** vcursor options can now be altered with M-x customize under the
3877Editing group once the package is loaded.
3878
3879*** Loading vcursor now does not define keys by default, as this is
3880generally a bad side effect. Use M-x customize to set
3881vcursor-key-bindings to t to restore the old behaviour.
3882
3883*** vcursor-auto-disable can be `copy', which turns off copying from the
3884vcursor, but doesn't disable it, after any non-vcursor command.
3885
3886** Ispell changes.
3887
79214ddf
FP
3888*** You can now spell check comments and strings in the current
3889buffer with M-x ispell-comments-and-strings. Comments and strings
a933dad1
DL
3890are identified by syntax tables in effect.
3891
3892*** Generic region skipping implemented.
3893A single buffer can be broken into a number of regions where text will
3894and will not be checked. The definitions of the regions can be user
3895defined. New applications and improvements made available by this
79214ddf 3896include:
a933dad1
DL
3897
3898 o URLs are automatically skipped
3899 o EMail message checking is vastly improved.
3900
3901*** Ispell can highlight the erroneous word even on non-window terminals.
3902
3903** Changes to RefTeX mode
3904
3905RefTeX has been updated in order to make it more usable with very
3906large projects (like a several volume math book). The parser has been
3907re-written from scratch. To get maximum speed from RefTeX, check the
3908section `Optimizations' in the manual.
3909
3910*** New recursive parser.
3911
3912The old version of RefTeX created a single large buffer containing the
3913entire multifile document in order to parse the document. The new
3914recursive parser scans the individual files.
3915
3916*** Parsing only part of a document.
79214ddf 3917
a933dad1
DL
3918Reparsing of changed document parts can now be made faster by enabling
3919partial scans. To use this feature, read the documentation string of
3920the variable `reftex-enable-partial-scans' and set the variable to t.
3921
3922 (setq reftex-enable-partial-scans t)
3923
3924*** Storing parsing information in a file.
3925
3926This can improve startup times considerably. To turn it on, use
3927
3928 (setq reftex-save-parse-info t)
3929
3930*** Using multiple selection buffers
3931
3932If the creation of label selection buffers is too slow (this happens
3933for large documents), you can reuse these buffers by setting
3934
3935 (setq reftex-use-multiple-selection-buffers t)
3936
3937*** References to external documents.
3938
3939The LaTeX package `xr' allows to cross-reference labels in external
3940documents. RefTeX can provide information about the external
3941documents as well. To use this feature, set up the \externaldocument
3942macros required by the `xr' package and rescan the document with
3943RefTeX. The external labels can then be accessed with the `x' key in
3944the selection buffer provided by `reftex-reference' (bound to `C-c )').
3945The `x' key also works in the table of contents buffer.
3946
3947*** Many more labeled LaTeX environments are recognized by default.
3948
3949The builtin command list now covers all the standard LaTeX commands,
3950and all of the major packages included in the LaTeX distribution.
3951
3952Also, RefTeX now understands the \appendix macro and changes
3953the enumeration of sections in the *toc* buffer accordingly.
3954
3955*** Mouse support for selection and *toc* buffers
3956
3957The mouse can now be used to select items in the selection and *toc*
3958buffers. See also the new option `reftex-highlight-selection'.
3959
3960*** New keymaps for selection and table of contents modes.
3961
3962The selection processes for labels and citation keys, and the table of
3963contents buffer now have their own keymaps: `reftex-select-label-map',
3964`reftex-select-bib-map', `reftex-toc-map'. The selection processes
3965have a number of new keys predefined. In particular, TAB lets you
3966enter a label with completion. Check the on-the-fly help (press `?'
3967at the selection prompt) or read the Info documentation to find out
3968more.
3969
3970*** Support for the varioref package
3971
3972The `v' key in the label selection buffer toggles \ref versus \vref.
3973
3974*** New hooks
3975
3976Three new hooks can be used to redefine the way labels, references,
3977and citations are created. These hooks are
3978`reftex-format-label-function', `reftex-format-ref-function',
3979`reftex-format-cite-function'.
3980
3981*** Citations outside LaTeX
3982
3983The command `reftex-citation' may also be used outside LaTeX (e.g. in
3984a mail buffer). See the Info documentation for details.
3985
3986*** Short context is no longer fontified.
3987
3988The short context in the label menu no longer copies the
3989fontification from the text in the buffer. If you prefer it to be
3990fontified, use
3991
3992 (setq reftex-refontify-context t)
3993
3994** file-cache-minibuffer-complete now accepts a prefix argument.
3995With a prefix argument, it does not try to do completion of
3996the file name within its directory; it only checks for other
3997directories that contain the same file name.
3998
3999Thus, given the file name Makefile, and assuming that a file
4000Makefile.in exists in the same directory, ordinary
4001file-cache-minibuffer-complete will try to complete Makefile to
4002Makefile.in and will therefore never look for other directories that
4003have Makefile. A prefix argument tells it not to look for longer
4004names such as Makefile.in, so that instead it will look for other
4005directories--just as if the name were already complete in its present
4006directory.
4007
4008** New modes and packages
4009
4010*** There is a new alternative major mode for Perl, Cperl mode.
4011It has many more features than Perl mode, and some people prefer
4012it, but some do not.
4013
4014*** There is a new major mode, M-x vhdl-mode, for editing files of VHDL
4015code.
4016
4017*** M-x which-function-mode enables a minor mode that displays the
4018current function name continuously in the mode line, as you move
4019around in a buffer.
4020
4021Which Function mode is effective in major modes which support Imenu.
4022
4023*** Gametree is a major mode for editing game analysis trees. The author
4024uses it for keeping notes about his postal Chess games, but it should
4025be helpful for other two-player games as well, as long as they have an
4026established system of notation similar to Chess.
4027
4028*** The new minor mode checkdoc-minor-mode provides Emacs Lisp
4029documentation string checking for style and spelling. The style
4030guidelines are found in the Emacs Lisp programming manual.
4031
4032*** The net-utils package makes some common networking features
4033available in Emacs. Some of these functions are wrappers around
4034system utilities (ping, nslookup, etc); others are implementations of
4035simple protocols (finger, whois) in Emacs Lisp. There are also
4036functions to make simple connections to TCP/IP ports for debugging and
4037the like.
4038
4039*** highlight-changes-mode is a minor mode that uses colors to
4040identify recently changed parts of the buffer text.
4041
4042*** The new package `midnight' lets you specify things to be done
4043within Emacs at midnight--by default, kill buffers that you have not
4044used in a considerable time. To use this feature, customize
4045the user option `midnight-mode' to t.
4046
4047*** The file generic-x.el defines a number of simple major modes.
4048
4049 apache-generic-mode: For Apache and NCSA httpd configuration files
4050 samba-generic-mode: Samba configuration files
4051 fvwm-generic-mode: For fvwm initialization files
4052 x-resource-generic-mode: For X resource files
4053 hosts-generic-mode: For hosts files (.rhosts, /etc/hosts, etc)
4054 mailagent-rules-generic-mode: For mailagent .rules files
4055 javascript-generic-mode: For JavaScript files
4056 vrml-generic-mode: For VRML files
4057 java-manifest-generic-mode: For Java MANIFEST files
4058 java-properties-generic-mode: For Java property files
4059 mailrc-generic-mode: For .mailrc files
4060
4061 Platform-specific modes:
4062
4063 prototype-generic-mode: For Solaris/Sys V prototype files
4064 pkginfo-generic-mode: For Solaris/Sys V pkginfo files
4065 alias-generic-mode: For C shell alias files
4066 inf-generic-mode: For MS-Windows INF files
4067 ini-generic-mode: For MS-Windows INI files
4068 reg-generic-mode: For MS-Windows Registry files
4069 bat-generic-mode: For MS-Windows BAT scripts
4070 rc-generic-mode: For MS-Windows Resource files
4071 rul-generic-mode: For InstallShield scripts
4072\f
4073* Lisp changes in Emacs 20.3 since the Emacs Lisp Manual was published
4074
4075** If you want a Lisp file to be read in unibyte mode,
4076use -*-unibyte: t;-*- on its first line.
4077That will force Emacs to read that file in unibyte mode.
4078Otherwise, the file will be loaded and byte-compiled in multibyte mode.
4079
4080Thus, each lisp file is read in a consistent way regardless of whether
4081you started Emacs with --unibyte, so that a Lisp program gives
4082consistent results regardless of how Emacs was started.
4083
4084** The new function assoc-default is useful for searching an alist,
4085and using a default value if the key is not found there. You can
4086specify a comparison predicate, so this function is useful for
4087searching comparing a string against an alist of regular expressions.
4088
4089** The functions unibyte-char-to-multibyte and
4090multibyte-char-to-unibyte convert between unibyte and multibyte
4091character codes, in a way that is appropriate for the current language
4092environment.
4093
4094** The functions read-event, read-char and read-char-exclusive now
4095take two optional arguments. PROMPT, if non-nil, specifies a prompt
4096string. SUPPRESS-INPUT-METHOD, if non-nil, says to disable the
4097current input method for reading this one event.
4098
4099** Two new variables print-escape-nonascii and print-escape-multibyte
4100now control whether to output certain characters as
4101backslash-sequences. print-escape-nonascii applies to single-byte
4102non-ASCII characters; print-escape-multibyte applies to multibyte
4103characters. Both of these variables are used only when printing
4104in readable fashion (prin1 uses them, princ does not).
4105\f
4106* Lisp changes in Emacs 20.3 before the Emacs Lisp Manual was published
4107
4108** Compiled Emacs Lisp files made with the modified "MBSK" version
4109of Emacs 20.2 do not work in Emacs 20.3.
4110
4111** Buffer positions are now measured in characters, as they were
4112in Emacs 19 and before. This means that (forward-char 1)
4113always increases point by 1.
4114
4115The function chars-in-region now just subtracts its arguments. It is
4116considered obsolete. The function char-boundary-p has been deleted.
4117
4118See below for additional changes relating to multibyte characters.
4119
4120** defcustom, defface and defgroup now accept the keyword `:version'.
4121Use this to specify in which version of Emacs a certain variable's
4122default value changed. For example,
4123
4124 (defcustom foo-max 34 "*Maximum number of foo's allowed."
4125 :type 'integer
4126 :group 'foo
4127 :version "20.3")
4128
79214ddf 4129 (defgroup foo-group nil "The foo group."
a933dad1
DL
4130 :version "20.3")
4131
4132If an entire new group is added or the variables in it have the
4133default values changed, then just add a `:version' to that group. It
4134is recommended that new packages added to the distribution contain a
4135`:version' in the top level group.
4136
4137This information is used to control the customize-changed-options command.
4138
4139** It is now an error to change the value of a symbol whose name
4140starts with a colon--if it is interned in the standard obarray.
4141
4142However, setting such a symbol to its proper value, which is that
4143symbol itself, is not an error. This is for the sake of programs that
4144support previous Emacs versions by explicitly setting these variables
4145to themselves.
4146
4147If you set the variable keyword-symbols-constant-flag to nil,
4148this error is suppressed, and you can set these symbols to any
4149values whatever.
4150
4151** There is a new debugger command, R.
4152It evaluates an expression like e, but saves the result
4153in the buffer *Debugger-record*.
4154
4155** Frame-local variables.
4156
4157You can now make a variable local to various frames. To do this, call
4158the function make-variable-frame-local; this enables frames to have
4159local bindings for that variable.
4160
4161These frame-local bindings are actually frame parameters: you create a
4162frame-local binding in a specific frame by calling
4163modify-frame-parameters and specifying the variable name as the
4164parameter name.
4165
4166Buffer-local bindings take precedence over frame-local bindings.
4167Thus, if the current buffer has a buffer-local binding, that binding is
4168active; otherwise, if the selected frame has a frame-local binding,
4169that binding is active; otherwise, the default binding is active.
4170
4171It would not be hard to implement window-local bindings, but it is not
4172clear that this would be very useful; windows tend to come and go in a
4173very transitory fashion, so that trying to produce any specific effect
4174through a window-local binding would not be very robust.
4175
4176** `sregexq' and `sregex' are two new functions for constructing
4177"symbolic regular expressions." These are Lisp expressions that, when
4178evaluated, yield conventional string-based regexps. The symbolic form
4179makes it easier to construct, read, and maintain complex patterns.
4180See the documentation in sregex.el.
4181
4182** parse-partial-sexp's return value has an additional element which
4183is used to pass information along if you pass it to another call to
4184parse-partial-sexp, starting its scan where the first call ended.
4185The contents of this field are not yet finalized.
4186
4187** eval-region now accepts a fourth optional argument READ-FUNCTION.
4188If it is non-nil, that function is used instead of `read'.
4189
4190** unload-feature by default removes the feature's functions from
4191known hooks to avoid trouble, but a package providing FEATURE can
4192define a hook FEATURE-unload-hook to be run by unload-feature instead.
4193
4194** read-from-minibuffer no longer returns the argument DEFAULT-VALUE
4195when the user enters empty input. It now returns the null string, as
4196it did in Emacs 19. The default value is made available in the
4197history via M-n, but it is not applied here as a default.
4198
4199The other, more specialized minibuffer-reading functions continue to
4200return the default value (not the null string) when the user enters
4201empty input.
4202
4203** The new variable read-buffer-function controls which routine to use
4204for selecting buffers. For example, if you set this variable to
4205`iswitchb-read-buffer', iswitchb will be used to read buffer names.
4206Other functions can also be used if they accept the same arguments as
4207`read-buffer' and return the selected buffer name as a string.
4208
4209** The new function read-passwd reads a password from the terminal,
4210echoing a period for each character typed. It takes three arguments:
4211a prompt string, a flag which says "read it twice to make sure", and a
4212default password to use if the user enters nothing.
4213
4214** The variable fill-nobreak-predicate gives major modes a way to
4215specify not to break a line at certain places. Its value is a
4216function which is called with no arguments, with point located at the
4217place where a break is being considered. If the function returns
4218non-nil, then the line won't be broken there.
4219
4220** window-end now takes an optional second argument, UPDATE.
4221If this is non-nil, then the function always returns an accurate
4222up-to-date value for the buffer position corresponding to the
4223end of the window, even if this requires computation.
4224
4225** other-buffer now takes an optional argument FRAME
4226which specifies which frame's buffer list to use.
4227If it is nil, that means use the selected frame's buffer list.
4228
4229** The new variable buffer-display-time, always local in every buffer,
4230holds the value of (current-time) as of the last time that a window
4231was directed to display this buffer.
4232
4233** It is now meaningful to compare two window-configuration objects
4234with `equal'. Two window-configuration objects are equal if they
4235describe equivalent arrangements of windows, in the same frame--in
4236other words, if they would give the same results if passed to
4237set-window-configuration.
4238
4239** compare-window-configurations is a new function that compares two
4240window configurations loosely. It ignores differences in saved buffer
4241positions and scrolling, and considers only the structure and sizes of
4242windows and the choice of buffers to display.
4243
4244** The variable minor-mode-overriding-map-alist allows major modes to
4245override the key bindings of a minor mode. The elements of this alist
4246look like the elements of minor-mode-map-alist: (VARIABLE . KEYMAP).
4247
4248If the VARIABLE in an element of minor-mode-overriding-map-alist has a
4249non-nil value, the paired KEYMAP is active, and totally overrides the
4250map (if any) specified for the same variable in minor-mode-map-alist.
4251
4252minor-mode-overriding-map-alist is automatically local in all buffers,
4253and it is meant to be set by major modes.
4254
4255** The function match-string-no-properties is like match-string
4256except that it discards all text properties from the result.
4257
4258** The function load-average now accepts an optional argument
4259USE-FLOATS. If it is non-nil, the load average values are returned as
4260floating point numbers, rather than as integers to be divided by 100.
4261
4262** The new variable temporary-file-directory specifies the directory
4263to use for creating temporary files. The default value is determined
4264in a reasonable way for your operating system; on GNU and Unix systems
4265it is based on the TMP and TMPDIR environment variables.
4266
4267** Menu changes
4268
4269*** easymenu.el now uses the new menu item format and supports the
4270keywords :visible and :filter. The existing keyword :keys is now
4271better supported.
4272
4273The variable `easy-menu-precalculate-equivalent-keybindings' controls
4274a new feature which calculates keyboard equivalents for the menu when
4275you define the menu. The default is t. If you rarely use menus, you
4276can set the variable to nil to disable this precalculation feature;
4277then the calculation is done only if you use the menu bar.
4278
4279*** A new format for menu items is supported.
4280
4281In a keymap, a key binding that has the format
4282 (STRING . REAL-BINDING) or (STRING HELP-STRING . REAL-BINDING)
4283defines a menu item. Now a menu item definition may also be a list that
4284starts with the symbol `menu-item'.
4285
4286The format is:
4287 (menu-item ITEM-NAME) or
4288 (menu-item ITEM-NAME REAL-BINDING . ITEM-PROPERTY-LIST)
4289where ITEM-NAME is an expression which evaluates to the menu item
4290string, and ITEM-PROPERTY-LIST has the form of a property list.
4291The supported properties include
4292
4293:enable FORM Evaluate FORM to determine whether the
4294 item is enabled.
4295:visible FORM Evaluate FORM to determine whether the
4296 item should appear in the menu.
79214ddf 4297:filter FILTER-FN
a933dad1
DL
4298 FILTER-FN is a function of one argument,
4299 which will be REAL-BINDING.
4300 It should return a binding to use instead.
4301:keys DESCRIPTION
4302 DESCRIPTION is a string that describes an equivalent keyboard
4303 binding for for REAL-BINDING. DESCRIPTION is expanded with
4304 `substitute-command-keys' before it is used.
4305:key-sequence KEY-SEQUENCE
4306 KEY-SEQUENCE is a key-sequence for an equivalent
4307 keyboard binding.
4308:key-sequence nil
4309 This means that the command normally has no
4310 keyboard equivalent.
4311:help HELP HELP is the extra help string (not currently used).
4312:button (TYPE . SELECTED)
4313 TYPE is :toggle or :radio.
4314 SELECTED is a form, to be evaluated, and its
4315 value says whether this button is currently selected.
4316
4317Buttons are at the moment only simulated by prefixes in the menu.
4318Eventually ordinary X-buttons may be supported.
4319
4320(menu-item ITEM-NAME) defines unselectable item.
4321
4322** New event types
4323
4324*** The new event type `mouse-wheel' is generated by a wheel on a
4325mouse (such as the MS Intellimouse). The event contains a delta that
4326corresponds to the amount and direction that the wheel is rotated,
4327which is typically used to implement a scroll or zoom. The format is:
4328
4329 (mouse-wheel POSITION DELTA)
4330
4331where POSITION is a list describing the position of the event in the
4332same format as a mouse-click event, and DELTA is a signed number
4333indicating the number of increments by which the wheel was rotated. A
4334negative DELTA indicates that the wheel was rotated backwards, towards
4335the user, and a positive DELTA indicates that the wheel was rotated
4336forward, away from the user.
4337
4338As of now, this event type is generated only on MS Windows.
4339
4340*** The new event type `drag-n-drop' is generated when a group of
4341files is selected in an application outside of Emacs, and then dragged
4342and dropped onto an Emacs frame. The event contains a list of
4343filenames that were dragged and dropped, which are then typically
4344loaded into Emacs. The format is:
4345
4346 (drag-n-drop POSITION FILES)
4347
4348where POSITION is a list describing the position of the event in the
4349same format as a mouse-click event, and FILES is the list of filenames
4350that were dragged and dropped.
4351
4352As of now, this event type is generated only on MS Windows.
4353
4354** Changes relating to multibyte characters.
4355
4356*** The variable enable-multibyte-characters is now read-only;
4357any attempt to set it directly signals an error. The only way
4358to change this value in an existing buffer is with set-buffer-multibyte.
4359
4360*** In a string constant, `\ ' now stands for "nothing at all". You
4361can use it to terminate a hex escape which is followed by a character
4362that could otherwise be read as part of the hex escape.
4363
4364*** String indices are now measured in characters, as they were
4365in Emacs 19 and before.
4366
4367The function chars-in-string has been deleted.
4368The function concat-chars has been renamed to `string'.
4369
4370*** The function set-buffer-multibyte sets the flag in the current
4371buffer that says whether the buffer uses multibyte representation or
4372unibyte representation. If the argument is nil, it selects unibyte
4373representation. Otherwise it selects multibyte representation.
4374
4375This function does not change the contents of the buffer, viewed
4376as a sequence of bytes. However, it does change the contents
4377viewed as characters; a sequence of two bytes which is treated as
4378one character when the buffer uses multibyte representation
4379will count as two characters using unibyte representation.
4380
4381This function sets enable-multibyte-characters to record which
4382representation is in use. It also adjusts various data in the buffer
4383(including its markers, overlays and text properties) so that they are
4384consistent with the new representation.
4385
4386*** string-make-multibyte takes a string and converts it to multibyte
4387representation. Most of the time, you don't need to care
4388about the representation, because Emacs converts when necessary;
4389however, it makes a difference when you compare strings.
4390
4391The conversion of non-ASCII characters works by adding the value of
4392nonascii-insert-offset to each character, or by translating them
4393using the table nonascii-translation-table.
4394
4395*** string-make-unibyte takes a string and converts it to unibyte
4396representation. Most of the time, you don't need to care about the
4397representation, but it makes a difference when you compare strings.
4398
4399The conversion from multibyte to unibyte representation
4400loses information; the only time Emacs performs it automatically
4401is when inserting a multibyte string into a unibyte buffer.
4402
4403*** string-as-multibyte takes a string, and returns another string
4404which contains the same bytes, but treats them as multibyte.
4405
4406*** string-as-unibyte takes a string, and returns another string
4407which contains the same bytes, but treats them as unibyte.
4408
4409*** The new function compare-strings lets you compare
4410portions of two strings. Unibyte strings are converted to multibyte,
4411so that a unibyte string can match a multibyte string.
4412You can specify whether to ignore case or not.
4413
4414*** assoc-ignore-case now uses compare-strings so that
4415it can treat unibyte and multibyte strings as equal.
4416
4417*** Regular expression operations and buffer string searches now
4418convert the search pattern to multibyte or unibyte to accord with the
4419buffer or string being searched.
4420
4421One consequence is that you cannot always use \200-\377 inside of
4422[...] to match all non-ASCII characters. This does still work when
4423searching or matching a unibyte buffer or string, but not when
4424searching or matching a multibyte string. Unfortunately, there is no
4425obvious choice of syntax to use within [...] for that job. But, what
4426you want is just to match all non-ASCII characters, the regular
4427expression [^\0-\177] works for it.
4428
4429*** Structure of coding system changed.
4430
4431All coding systems (including aliases and subsidiaries) are named
4432by symbols; the symbol's `coding-system' property is a vector
4433which defines the coding system. Aliases share the same vector
4434as the principal name, so that altering the contents of this
4435vector affects the principal name and its aliases. You can define
4436your own alias name of a coding system by the function
4437define-coding-system-alias.
4438
4439The coding system definition includes a property list of its own. Use
4440the new functions `coding-system-get' and `coding-system-put' to
4441access such coding system properties as post-read-conversion,
4442pre-write-conversion, character-translation-table-for-decode,
4443character-translation-table-for-encode, mime-charset, and
4444safe-charsets. For instance, (coding-system-get 'iso-latin-1
4445'mime-charset) gives the corresponding MIME-charset parameter
4446`iso-8859-1'.
4447
4448Among the coding system properties listed above, safe-charsets is new.
4449The value of this property is a list of character sets which this
4450coding system can correctly encode and decode. For instance:
4451(coding-system-get 'iso-latin-1 'safe-charsets) => (ascii latin-iso8859-1)
4452
4453Here, "correctly encode" means that the encoded character sets can
4454also be handled safely by systems other than Emacs as far as they
4455are capable of that coding system. Though, Emacs itself can encode
4456the other character sets and read it back correctly.
4457
4458*** The new function select-safe-coding-system can be used to find a
4459proper coding system for encoding the specified region or string.
4460This function requires a user interaction.
4461
4462*** The new functions find-coding-systems-region and
4463find-coding-systems-string are helper functions used by
4464select-safe-coding-system. They return a list of all proper coding
4465systems to encode a text in some region or string. If you don't want
4466a user interaction, use one of these functions instead of
4467select-safe-coding-system.
4468
4469*** The explicit encoding and decoding functions, such as
4470decode-coding-region and encode-coding-string, now set
4471last-coding-system-used to reflect the actual way encoding or decoding
4472was done.
4473
4474*** The new function detect-coding-with-language-environment can be
4475used to detect a coding system of text according to priorities of
4476coding systems used by some specific language environment.
4477
4478*** The functions detect-coding-region and detect-coding-string always
4479return a list if the arg HIGHEST is nil. Thus, if only ASCII
4480characters are found, they now return a list of single element
4481`undecided' or its subsidiaries.
4482
4483*** The new functions coding-system-change-eol-conversion and
4484coding-system-change-text-conversion can be used to get a different
4485coding system than what specified only in how end-of-line or text is
4486converted.
4487
4488*** The new function set-selection-coding-system can be used to set a
4489coding system for communicating with other X clients.
4490
4491*** The function `map-char-table' now passes as argument only valid
4492character codes, plus generic characters that stand for entire
4493character sets or entire subrows of a character set. In other words,
4494each time `map-char-table' calls its FUNCTION argument, the key value
4495either will be a valid individual character code, or will stand for a
4496range of characters.
4497
4498*** The new function `char-valid-p' can be used for checking whether a
4499Lisp object is a valid character code or not.
4500
4501*** The new function `charset-after' returns a charset of a character
4502in the current buffer at position POS.
4503
4504*** Input methods are now implemented using the variable
4505input-method-function. If this is non-nil, its value should be a
4506function; then, whenever Emacs reads an input event that is a printing
4507character with no modifier bits, it calls that function, passing the
4508event as an argument. Often this function will read more input, first
4509binding input-method-function to nil.
4510
4511The return value should be a list of the events resulting from input
4512method processing. These events will be processed sequentially as
4513input, before resorting to unread-command-events. Events returned by
4514the input method function are not passed to the input method function,
4515not even if they are printing characters with no modifier bits.
4516
4517The input method function is not called when reading the second and
4518subsequent events of a key sequence.
4519
4520*** You can customize any language environment by using
4521set-language-environment-hook and exit-language-environment-hook.
4522
4523The hook `exit-language-environment-hook' should be used to undo
4524customizations that you made with set-language-environment-hook. For
4525instance, if you set up a special key binding for a specific language
4526environment by set-language-environment-hook, you should set up
4527exit-language-environment-hook to restore the normal key binding.
4528\f
4529* Changes in Emacs 20.1
4530
4531** Emacs has a new facility for customization of its many user
4532options. It is called M-x customize. With this facility you can look
4533at the many user options in an organized way; they are grouped into a
4534tree structure.
4535
4536M-x customize also knows what sorts of values are legitimate for each
4537user option and ensures that you don't use invalid values.
4538
4539With M-x customize, you can set options either for the present Emacs
4540session or permanently. (Permanent settings are stored automatically
4541in your .emacs file.)
4542
4543** Scroll bars are now on the left side of the window.
4544You can change this with M-x customize-option scroll-bar-mode.
4545
4546** The mode line no longer includes the string `Emacs'.
4547This makes more space in the mode line for other information.
4548
4549** When you select a region with the mouse, it is highlighted
4550immediately afterward. At that time, if you type the DELETE key, it
4551kills the region.
4552
4553The BACKSPACE key, and the ASCII character DEL, do not do this; they
4554delete the character before point, as usual.
4555
4556** In an incremental search the whole current match is highlighted
4557on terminals which support this. (You can disable this feature
4558by setting search-highlight to nil.)
4559
4560** In the minibuffer, in some cases, you can now use M-n to
4561insert the default value into the minibuffer as text. In effect,
4562the default value (if the minibuffer routines know it) is tacked
4563onto the history "in the future". (The more normal use of the
4564history list is to use M-p to insert minibuffer input used in the
4565past.)
4566
4567** In Text mode, now only blank lines separate paragraphs.
4568This makes it possible to get the full benefit of Adaptive Fill mode
4569in Text mode, and other modes derived from it (such as Mail mode).
4570TAB in Text mode now runs the command indent-relative; this
4571makes a practical difference only when you use indented paragraphs.
4572
4573As a result, the old Indented Text mode is now identical to Text mode,
4574and is an alias for it.
4575
4576If you want spaces at the beginning of a line to start a paragraph,
4577use the new mode, Paragraph Indent Text mode.
4578
4579** Scrolling changes
4580
4581*** Scroll commands to scroll a whole screen now preserve the screen
4582position of the cursor, if scroll-preserve-screen-position is non-nil.
4583
4584In this mode, if you scroll several screens back and forth, finishing
4585on the same screen where you started, the cursor goes back to the line
4586where it started.
4587
4588*** If you set scroll-conservatively to a small number, then when you
4589move point a short distance off the screen, Emacs will scroll the
4590screen just far enough to bring point back on screen, provided that
4591does not exceed `scroll-conservatively' lines.
4592
4593*** The new variable scroll-margin says how close point can come to the
4594top or bottom of a window. It is a number of screen lines; if point
4595comes within that many lines of the top or bottom of the window, Emacs
4596recenters the window.
4597
4598** International character set support (MULE)
4599
4600Emacs now supports a wide variety of international character sets,
4601including European variants of the Latin alphabet, as well as Chinese,
4602Devanagari (Hindi and Marathi), Ethiopian, Greek, IPA, Japanese,
4603Korean, Lao, Russian, Thai, Tibetan, and Vietnamese scripts. These
4604features have been merged from the modified version of Emacs known as
4605MULE (for "MULti-lingual Enhancement to GNU Emacs")
4606
4607Users of these scripts have established many more-or-less standard
4608coding systems for storing files. Emacs uses a single multibyte
4609character encoding within Emacs buffers; it can translate from a wide
4610variety of coding systems when reading a file and can translate back
4611into any of these coding systems when saving a file.
4612
4613Keyboards, even in the countries where these character sets are used,
4614generally don't have keys for all the characters in them. So Emacs
4615supports various "input methods", typically one for each script or
4616language, to make it possible to type them.
4617
4618The Emacs internal multibyte encoding represents a non-ASCII
4619character as a sequence of bytes in the range 0200 through 0377.
4620
4621The new prefix key C-x RET is used for commands that pertain
4622to multibyte characters, coding systems, and input methods.
4623
4624You can disable multibyte character support as follows:
4625
4626 (setq-default enable-multibyte-characters nil)
4627
4628Calling the function standard-display-european turns off multibyte
4629characters, unless you specify a non-nil value for the second
4630argument, AUTO. This provides compatibility for people who are
4631already using standard-display-european to continue using unibyte
4632characters for their work until they want to change.
4633
4634*** Input methods
4635
4636An input method is a kind of character conversion which is designed
4637specifically for interactive input. In Emacs, typically each language
4638has its own input method (though sometimes several languages which use
4639the same characters can share one input method). Some languages
4640support several input methods.
4641
4642The simplest kind of input method works by mapping ASCII letters into
4643another alphabet. This is how the Greek and Russian input methods
4644work.
4645
4646A more powerful technique is composition: converting sequences of
4647characters into one letter. Many European input methods use
4648composition to produce a single non-ASCII letter from a sequence which
4649consists of a letter followed by diacritics. For example, a' is one
4650sequence of two characters that might be converted into a single
4651letter.
4652
4653The input methods for syllabic scripts typically use mapping followed
4654by conversion. The input methods for Thai and Korean work this way.
4655First, letters are mapped into symbols for particular sounds or tone
4656marks; then, sequences of these which make up a whole syllable are
4657mapped into one syllable sign--most often a "composite character".
4658
4659None of these methods works very well for Chinese and Japanese, so
4660they are handled specially. First you input a whole word using
4661phonetic spelling; then, after the word is in the buffer, Emacs
4662converts it into one or more characters using a large dictionary.
4663
4664Since there is more than one way to represent a phonetically spelled
4665word using Chinese characters, Emacs can only guess which one to use;
4666typically these input methods give you a way to say "guess again" if
4667the first guess is wrong.
4668
4669*** The command C-x RET m (toggle-enable-multibyte-characters)
4670turns multibyte character support on or off for the current buffer.
4671
4672If multibyte character support is turned off in a buffer, then each
4673byte is a single character, even codes 0200 through 0377--exactly as
4674they did in Emacs 19.34. This includes the features for support for
4675the European characters, ISO Latin-1 and ISO Latin-2.
4676
4677However, there is no need to turn off multibyte character support to
4678use ISO Latin-1 or ISO Latin-2; the Emacs multibyte character set
4679includes all the characters in these character sets, and Emacs can
4680translate automatically to and from either one.
4681
4682*** Visiting a file in unibyte mode.
4683
4684Turning off multibyte character support in the buffer after visiting a
4685file with multibyte code conversion will display the multibyte
4686sequences already in the buffer, byte by byte. This is probably not
4687what you want.
4688
4689If you want to edit a file of unibyte characters (Latin-1, for
4690example), you can do it by specifying `no-conversion' as the coding
4691system when reading the file. This coding system also turns off
4692multibyte characters in that buffer.
4693
4694If you turn off multibyte character support entirely, this turns off
4695character conversion as well.
4696
4697*** Displaying international characters on X Windows.
4698
4699A font for X typically displays just one alphabet or script.
4700Therefore, displaying the entire range of characters Emacs supports
4701requires using many fonts.
4702
4703Therefore, Emacs now supports "fontsets". Each fontset is a
4704collection of fonts, each assigned to a range of character codes.
4705
4706A fontset has a name, like a font. Individual fonts are defined by
4707the X server; fontsets are defined within Emacs itself. But once you
4708have defined a fontset, you can use it in a face or a frame just as
4709you would use a font.
4710
4711If a fontset specifies no font for a certain character, or if it
4712specifies a font that does not exist on your system, then it cannot
4713display that character. It will display an empty box instead.
4714
4715The fontset height and width are determined by the ASCII characters
4716(that is, by the font in the fontset which is used for ASCII
4717characters). If another font in the fontset has a different height,
4718or the wrong width, then characters assigned to that font are clipped,
4719and displayed within a box if highlight-wrong-size-font is non-nil.
4720
4721*** Defining fontsets.
4722
4723Emacs does not use any fontset by default. Its default font is still
4724chosen as in previous versions. You can tell Emacs to use a fontset
4725with the `-fn' option or the `Font' X resource.
4726
4727Emacs creates a standard fontset automatically according to the value
4728of standard-fontset-spec. This fontset's short name is
4729`fontset-standard'. Bold, italic, and bold-italic variants of the
4730standard fontset are created automatically.
4731
4732If you specify a default ASCII font with the `Font' resource or `-fn'
4733argument, a fontset is generated from it. This works by replacing the
4734FOUNDARY, FAMILY, ADD_STYLE, and AVERAGE_WIDTH fields of the font name
4735with `*' then using this to specify a fontset. This fontset's short
4736name is `fontset-startup'.
4737
4738Emacs checks resources of the form Fontset-N where N is 0, 1, 2...
4739The resource value should have this form:
4740 FONTSET-NAME, [CHARSET-NAME:FONT-NAME]...
4741FONTSET-NAME should have the form of a standard X font name, except:
4742 * most fields should be just the wild card "*".
4743 * the CHARSET_REGISTRY field should be "fontset"
4744 * the CHARSET_ENCODING field can be any nickname of the fontset.
4745The construct CHARSET-NAME:FONT-NAME can be repeated any number
4746of times; each time specifies the font for one character set.
4747CHARSET-NAME should be the name name of a character set, and
4748FONT-NAME should specify an actual font to use for that character set.
4749
4750Each of these fontsets has an alias which is made from the
4751last two font name fields, CHARSET_REGISTRY and CHARSET_ENCODING.
4752You can refer to the fontset by that alias or by its full name.
4753
4754For any character sets that you don't mention, Emacs tries to choose a
4755font by substituting into FONTSET-NAME. For instance, with the
4756following resource,
4757 Emacs*Fontset-0: -*-fixed-medium-r-normal-*-24-*-*-*-*-*-fontset-24
4758the font for ASCII is generated as below:
4759 -*-fixed-medium-r-normal-*-24-*-ISO8859-1
4760Here is the substitution rule:
4761 Change CHARSET_REGISTRY and CHARSET_ENCODING to that of the charset
4762 defined in the variable x-charset-registries. For instance, ASCII has
4763 the entry (ascii . "ISO8859-1") in this variable. Then, reduce
4764 sequences of wild cards -*-...-*- with a single wildcard -*-.
4765 (This is to prevent use of auto-scaled fonts.)
4766
4767The function which processes the fontset resource value to create the
4768fontset is called create-fontset-from-fontset-spec. You can also call
4769that function explicitly to create a fontset.
4770
4771With the X resource Emacs.Font, you can specify a fontset name just
4772like an actual font name. But be careful not to specify a fontset
4773name in a wildcard resource like Emacs*Font--that tries to specify the
4774fontset for other purposes including menus, and they cannot handle
4775fontsets.
4776
4777*** The command M-x set-language-environment sets certain global Emacs
4778defaults for a particular choice of language.
4779
4780Selecting a language environment typically specifies a default input
4781method and which coding systems to recognize automatically when
4782visiting files. However, it does not try to reread files you have
4783already visited; the text in those buffers is not affected. The
4784language environment may also specify a default choice of coding
4785system for new files that you create.
4786
4787It makes no difference which buffer is current when you use
4788set-language-environment, because these defaults apply globally to the
4789whole Emacs session.
4790
4791For example, M-x set-language-environment RET Latin-1 RET
4792chooses the Latin-1 character set. In the .emacs file, you can do this
4793with (set-language-environment "Latin-1").
4794
4795*** The command C-x RET f (set-buffer-file-coding-system)
4796specifies the file coding system for the current buffer. This
4797specifies what sort of character code translation to do when saving
4798the file. As an argument, you must specify the name of one of the
4799coding systems that Emacs supports.
4800
4801*** The command C-x RET c (universal-coding-system-argument)
4802lets you specify a coding system when you read or write a file.
4803This command uses the minibuffer to read a coding system name.
4804After you exit the minibuffer, the specified coding system
4805is used for *the immediately following command*.
4806
4807So if the immediately following command is a command to read or
4808write a file, it uses the specified coding system for that file.
4809
4810If the immediately following command does not use the coding system,
4811then C-x RET c ultimately has no effect.
4812
4813For example, C-x RET c iso-8859-1 RET C-x C-f temp RET
4814visits the file `temp' treating it as ISO Latin-1.
4815
4816*** You can specify the coding system for a file using the -*-
4817construct. Include `coding: CODINGSYSTEM;' inside the -*-...-*-
4818to specify use of coding system CODINGSYSTEM. You can also
4819specify the coding system in a local variable list at the end
4820of the file.
4821
4822*** The command C-x RET t (set-terminal-coding-system) specifies
4823the coding system for terminal output. If you specify a character
4824code for terminal output, all characters output to the terminal are
4825translated into that character code.
4826
4827This feature is useful for certain character-only terminals built in
4828various countries to support the languages of those countries.
4829
4830By default, output to the terminal is not translated at all.
4831
4832*** The command C-x RET k (set-keyboard-coding-system) specifies
4833the coding system for keyboard input.
4834
4835Character code translation of keyboard input is useful for terminals
4836with keys that send non-ASCII graphic characters--for example,
4837some terminals designed for ISO Latin-1 or subsets of it.
4838
4839By default, keyboard input is not translated at all.
4840
4841Character code translation of keyboard input is similar to using an
4842input method, in that both define sequences of keyboard input that
4843translate into single characters. However, input methods are designed
4844to be convenient for interactive use, while the code translations are
4845designed to work with terminals.
4846
4847*** The command C-x RET p (set-buffer-process-coding-system)
4848specifies the coding system for input and output to a subprocess.
4849This command applies to the current buffer; normally, each subprocess
4850has its own buffer, and thus you can use this command to specify
4851translation to and from a particular subprocess by giving the command
4852in the corresponding buffer.
4853
4854By default, process input and output are not translated at all.
4855
4856*** The variable file-name-coding-system specifies the coding system
4857to use for encoding file names before operating on them.
4858It is also used for decoding file names obtained from the system.
4859
4860*** The command C-\ (toggle-input-method) activates or deactivates
4861an input method. If no input method has been selected before, the
4862command prompts for you to specify the language and input method you
4863want to use.
4864
4865C-u C-\ (select-input-method) lets you switch to a different input
4866method. C-h C-\ (or C-h I) describes the current input method.
4867
4868*** Some input methods remap the keyboard to emulate various keyboard
4869layouts commonly used for particular scripts. How to do this
4870remapping properly depends on your actual keyboard layout. To specify
4871which layout your keyboard has, use M-x quail-set-keyboard-layout.
4872
4873*** The command C-h C (describe-coding-system) displays
4874the coding systems currently selected for various purposes, plus
4875related information.
4876
4877*** The command C-h h (view-hello-file) displays a file called
4878HELLO, which has examples of text in many languages, using various
4879scripts.
4880
4881*** The command C-h L (describe-language-support) displays
4882information about the support for a particular language.
4883You specify the language as an argument.
4884
4885*** The mode line now contains a letter or character that identifies
4886the coding system used in the visited file. It normally follows the
4887first dash.
4888
4889A dash indicates the default state of affairs: no code conversion
4890(except CRLF => newline if appropriate). `=' means no conversion
4891whatsoever. The ISO 8859 coding systems are represented by digits
48921 through 9. Other coding systems are represented by letters:
4893
4894 A alternativnyj (Russian)
4895 B big5 (Chinese)
4896 C cn-gb-2312 (Chinese)
4897 C iso-2022-cn (Chinese)
4898 D in-is13194-devanagari (Indian languages)
4899 E euc-japan (Japanese)
4900 I iso-2022-cjk or iso-2022-ss2 (Chinese, Japanese, Korean)
4901 J junet (iso-2022-7) or old-jis (iso-2022-jp-1978-irv) (Japanese)
4902 K euc-korea (Korean)
4903 R koi8 (Russian)
4904 Q tibetan
4905 S shift_jis (Japanese)
4906 T lao
4907 T tis620 (Thai)
4908 V viscii or vscii (Vietnamese)
4909 i iso-2022-lock (Chinese, Japanese, Korean)
4910 k iso-2022-kr (Korean)
4911 v viqr (Vietnamese)
4912 z hz (Chinese)
4913
4914When you are using a character-only terminal (not a window system),
4915two additional characters appear in between the dash and the file
4916coding system. These two characters describe the coding system for
4917keyboard input, and the coding system for terminal output.
4918
4919*** The new variable rmail-file-coding-system specifies the code
4920conversion to use for RMAIL files. The default value is nil.
4921
4922When you read mail with Rmail, each message is decoded automatically
4923into Emacs' internal format. This has nothing to do with
4924rmail-file-coding-system. That variable controls reading and writing
4925Rmail files themselves.
4926
4927*** The new variable sendmail-coding-system specifies the code
4928conversion for outgoing mail. The default value is nil.
4929
4930Actually, there are three different ways of specifying the coding system
4931for sending mail:
4932
4933- If you use C-x RET f in the mail buffer, that takes priority.
4934- Otherwise, if you set sendmail-coding-system non-nil, that specifies it.
4935- Otherwise, the default coding system for new files is used,
4936 if that is non-nil. That comes from your language environment.
4937- Otherwise, Latin-1 is used.
4938
4939*** The command C-h t (help-with-tutorial) accepts a prefix argument
4940to specify the language for the tutorial file. Currently, English,
4941Japanese, Korean and Thai are supported. We welcome additional
4942translations.
4943
4944** An easy new way to visit a file with no code or format conversion
4945of any kind: Use M-x find-file-literally. There is also a command
4946insert-file-literally which inserts a file into the current buffer
4947without any conversion.
4948
4949** C-q's handling of octal character codes is changed.
4950You can now specify any number of octal digits.
4951RET terminates the digits and is discarded;
4952any other non-digit terminates the digits and is then used as input.
4953
4954** There are new commands for looking up Info documentation for
4955functions, variables and file names used in your programs.
4956
4957Type M-x info-lookup-symbol to look up a symbol in the buffer at point.
4958Type M-x info-lookup-file to look up a file in the buffer at point.
4959
4960Precisely which Info files are used to look it up depends on the major
4961mode. For example, in C mode, the GNU libc manual is used.
4962
4963** M-TAB in most programming language modes now runs the command
4964complete-symbol. This command performs completion on the symbol name
4965in the buffer before point.
4966
4967With a numeric argument, it performs completion based on the set of
4968symbols documented in the Info files for the programming language that
4969you are using.
4970
4971With no argument, it does completion based on the current tags tables,
4972just like the old binding of M-TAB (complete-tag).
4973
4974** File locking works with NFS now.
4975
4976The lock file for FILENAME is now a symbolic link named .#FILENAME,
4977in the same directory as FILENAME.
4978
4979This means that collision detection between two different machines now
4980works reasonably well; it also means that no file server or directory
4981can become a bottleneck.
4982
4983The new method does have drawbacks. It means that collision detection
4984does not operate when you edit a file in a directory where you cannot
4985create new files. Collision detection also doesn't operate when the
4986file server does not support symbolic links. But these conditions are
4987rare, and the ability to have collision detection while using NFS is
4988so useful that the change is worth while.
4989
4990When Emacs or a system crashes, this may leave behind lock files which
4991are stale. So you may occasionally get warnings about spurious
4992collisions. When you determine that the collision is spurious, just
4993tell Emacs to go ahead anyway.
4994
4995** If you wish to use Show Paren mode to display matching parentheses,
4996it is no longer sufficient to load paren.el. Instead you must call
4997show-paren-mode.
4998
4999** If you wish to use Delete Selection mode to replace a highlighted
5000selection when you insert new text, it is no longer sufficient to load
5001delsel.el. Instead you must call the function delete-selection-mode.
5002
5003** If you wish to use Partial Completion mode to complete partial words
5004within symbols or filenames, it is no longer sufficient to load
5005complete.el. Instead you must call the function partial-completion-mode.
5006
5007** If you wish to use uniquify to rename buffers for you,
5008it is no longer sufficient to load uniquify.el. You must also
5009set uniquify-buffer-name-style to one of the non-nil legitimate values.
5010
5011** Changes in View mode.
5012
5013*** Several new commands are available in View mode.
5014Do H in view mode for a list of commands.
5015
5016*** There are two new commands for entering View mode:
5017view-file-other-frame and view-buffer-other-frame.
5018
5019*** Exiting View mode does a better job of restoring windows to their
5020previous state.
5021
5022*** New customization variable view-scroll-auto-exit. If non-nil,
5023scrolling past end of buffer makes view mode exit.
5024
5025*** New customization variable view-exits-all-viewing-windows. If
5026non-nil, view-mode will at exit restore all windows viewing buffer,
5027not just the selected window.
5028
5029*** New customization variable view-read-only. If non-nil, visiting a
5030read-only file automatically enters View mode, and toggle-read-only
5031turns View mode on or off.
5032
5033*** New customization variable view-remove-frame-by-deleting controls
5034how to remove a not needed frame at view mode exit. If non-nil,
5035delete the frame, if nil make an icon of it.
5036
5037** C-x v l, the command to print a file's version control log,
5038now positions point at the entry for the file's current branch version.
5039
5040** C-x v =, the command to compare a file with the last checked-in version,
5041has a new feature. If the file is currently not locked, so that it is
5042presumably identical to the last checked-in version, the command now asks
5043which version to compare with.
5044
5045** When using hideshow.el, incremental search can temporarily show hidden
79214ddf 5046blocks if a match is inside the block.
a933dad1
DL
5047
5048The block is hidden again if the search is continued and the next match
5049is outside the block. By customizing the variable
5050isearch-hide-immediately you can choose to hide all the temporarily
5051shown blocks only when exiting from incremental search.
5052
5053By customizing the variable hs-isearch-open you can choose what kind
5054of blocks to temporarily show during isearch: comment blocks, code
5055blocks, all of them or none.
5056
5057** The new command C-x 4 0 (kill-buffer-and-window) kills the
5058current buffer and deletes the selected window. It asks for
5059confirmation first.
5060
5061** C-x C-w, which saves the buffer into a specified file name,
5062now changes the major mode according to that file name.
5063However, the mode will not be changed if
5064(1) a local variables list or the `-*-' line specifies a major mode, or
5065(2) the current major mode is a "special" mode,
5066 not suitable for ordinary files, or
5067(3) the new file name does not particularly specify any mode.
5068
5069This applies to M-x set-visited-file-name as well.
5070
5071However, if you set change-major-mode-with-file-name to nil, then
5072these commands do not change the major mode.
5073
5074** M-x occur changes.
5075
5076*** If the argument to M-x occur contains upper case letters,
5077it performs a case-sensitive search.
5078
5079*** In the *Occur* buffer made by M-x occur,
5080if you type g or M-x revert-buffer, this repeats the search
5081using the same regular expression and the same buffer as before.
5082
5083** In Transient Mark mode, the region in any one buffer is highlighted
5084in just one window at a time. At first, it is highlighted in the
5085window where you set the mark. The buffer's highlighting remains in
5086that window unless you select to another window which shows the same
5087buffer--then the highlighting moves to that window.
5088
5089** The feature to suggest key bindings when you use M-x now operates
5090after the command finishes. The message suggesting key bindings
5091appears temporarily in the echo area. The previous echo area contents
5092come back after a few seconds, in case they contain useful information.
5093
5094** Each frame now independently records the order for recently
5095selected buffers, so that the default for C-x b is now based on the
5096buffers recently selected in the selected frame.
5097
5098** Outline mode changes.
5099
5100*** Outline mode now uses overlays (this is the former noutline.el).
5101
5102*** Incremental searches skip over invisible text in Outline mode.
5103
5104** When a minibuffer window is active but not the selected window, if
5105you try to use the minibuffer, you used to get a nested minibuffer.
5106Now, this not only gives an error, it also cancels the minibuffer that
5107was already active.
5108
5109The motive for this change is so that beginning users do not
5110unknowingly move away from minibuffers, leaving them active, and then
5111get confused by it.
5112
5113If you want to be able to have recursive minibuffers, you must
5114set enable-recursive-minibuffers to non-nil.
5115
5116** Changes in dynamic abbrevs.
5117
5118*** Expanding dynamic abbrevs with M-/ is now smarter about case
5119conversion. If the expansion has mixed case not counting the first
5120character, and the abbreviation matches the beginning of the expansion
5121including case, then the expansion is copied verbatim.
5122
5123The expansion is also copied verbatim if the abbreviation itself has
5124mixed case. And using SPC M-/ to copy an additional word always
5125copies it verbatim except when the previous copied word is all caps.
5126
5127*** The values of `dabbrev-case-replace' and `dabbrev-case-fold-search'
5128are no longer Lisp expressions. They have simply three possible
5129values.
5130
5131`dabbrev-case-replace' has these three values: nil (don't preserve
5132case), t (do), or `case-replace' (do like M-x query-replace).
5133`dabbrev-case-fold-search' has these three values: nil (don't ignore
5134case), t (do), or `case-fold-search' (do like search).
5135
5136** Minibuffer history lists are truncated automatically now to a
5137certain length. The variable history-length specifies how long they
5138can be. The default value is 30.
5139
5140** Changes in Mail mode.
5141
5142*** The key C-x m no longer runs the `mail' command directly.
5143Instead, it runs the command `compose-mail', which invokes the mail
5144composition mechanism you have selected with the variable
5145`mail-user-agent'. The default choice of user agent is
5146`sendmail-user-agent', which gives behavior compatible with the old
5147behavior.
5148
5149C-x 4 m now runs compose-mail-other-window, and C-x 5 m runs
5150compose-mail-other-frame.
5151
5152*** While composing a reply to a mail message, from Rmail, you can use
5153the command C-c C-r to cite just the region from the message you are
5154replying to. This copies the text which is the selected region in the
5155buffer that shows the original message.
5156
5157*** The command C-c C-i inserts a file at the end of the message,
5158with separator lines around the contents.
5159
5160*** The command M-x expand-mail-aliases expands all mail aliases
5161in suitable mail headers. Emacs automatically extracts mail alias
5162definitions from your mail alias file (e.g., ~/.mailrc). You do not
5163need to expand mail aliases yourself before sending mail.
5164
5165*** New features in the mail-complete command.
5166
5167**** The mail-complete command now inserts the user's full name,
5168for local users or if that is known. The variable mail-complete-style
5169controls the style to use, and whether to do this at all.
5170Its values are like those of mail-from-style.
5171
5172**** The variable mail-passwd-command lets you specify a shell command
5173to run to fetch a set of password-entries that add to the ones in
5174/etc/passwd.
5175
5176**** The variable mail-passwd-file now specifies a list of files to read
5177to get the list of user ids. By default, one file is used:
5178/etc/passwd.
5179
5180** You can "quote" a file name to inhibit special significance of
5181special syntax, by adding `/:' to the beginning. Thus, if you have a
5182directory named `/foo:', you can prevent it from being treated as a
5183reference to a remote host named `foo' by writing it as `/:/foo:'.
5184
5185Emacs uses this new construct automatically when necessary, such as
5186when you start it with a working directory whose name might otherwise
5187be taken to be magic.
5188
5189** There is a new command M-x grep-find which uses find to select
5190files to search through, and grep to scan them. The output is
5191available in a Compile mode buffer, as with M-x grep.
5192
5193M-x grep now uses the -e option if the grep program supports that.
5194(-e prevents problems if the search pattern starts with a dash.)
5195
5196** In Dired, the & command now flags for deletion the files whose names
5197suggest they are probably not needed in the long run.
5198
5199In Dired, * is now a prefix key for mark-related commands.
5200
5201new key dired.el binding old key
5202------- ---------------- -------
5203 * c dired-change-marks c
5204 * m dired-mark m
5205 * * dired-mark-executables * (binding deleted)
5206 * / dired-mark-directories / (binding deleted)
5207 * @ dired-mark-symlinks @ (binding deleted)
5208 * u dired-unmark u
5209 * DEL dired-unmark-backward DEL
5210 * ? dired-unmark-all-files M-C-?
5211 * ! dired-unmark-all-marks
5212 * % dired-mark-files-regexp % m
5213 * C-n dired-next-marked-file M-}
5214 * C-p dired-prev-marked-file M-{
5215
5216** Rmail changes.
5217
5218*** When Rmail cannot convert your incoming mail into Babyl format, it
5219saves the new mail in the file RMAILOSE.n, where n is an integer
5220chosen to make a unique name. This way, Rmail will not keep crashing
5221each time you run it.
5222
5223*** In Rmail, the variable rmail-summary-line-count-flag now controls
5224whether to include the line count in the summary. Non-nil means yes.
5225
5226*** In Rmail summary buffers, d and C-d (the commands to delete
5227messages) now take repeat counts as arguments. A negative argument
5228means to move in the opposite direction.
5229
5230*** In Rmail, the t command now takes an optional argument which lets
5231you specify whether to show the message headers in full or pruned.
5232
5233*** In Rmail, the new command w (rmail-output-body-to-file) writes
5234just the body of the current message into a file, without the headers.
5235It takes the file name from the message subject, by default, but you
5236can edit that file name in the minibuffer before it is actually used
5237for output.
5238
5239** Gnus changes.
5240
5241*** nntp.el has been totally rewritten in an asynchronous fashion.
5242
79214ddf
FP
5243*** Article prefetching functionality has been moved up into
5244Gnus.
a933dad1 5245
79214ddf 5246*** Scoring can now be performed with logical operators like
a933dad1
DL
5247`and', `or', `not', and parent redirection.
5248
5249*** Article washing status can be displayed in the
5250article mode line.
5251
5252*** gnus.el has been split into many smaller files.
5253
5254*** Suppression of duplicate articles based on Message-ID.
5255
5256(setq gnus-suppress-duplicates t)
5257
5258*** New variables for specifying what score and adapt files
5259are to be considered home score and adapt files. See
5260`gnus-home-score-file' and `gnus-home-adapt-files'.
5261
5262*** Groups can inherit group parameters from parent topics.
5263
5264*** Article editing has been revamped and is now usable.
5265
5266*** Signatures can be recognized in more intelligent fashions.
5267See `gnus-signature-separator' and `gnus-signature-limit'.
5268
5269*** Summary pick mode has been made to look more nn-like.
5270Line numbers are displayed and the `.' command can be
5271used to pick articles.
5272
5273*** Commands for moving the .newsrc.eld from one server to
5274another have been added.
5275
5276 `M-x gnus-change-server'
5277
5278*** A way to specify that "uninteresting" fields be suppressed when
5279generating lines in buffers.
5280
5281*** Several commands in the group buffer can be undone with
5282`M-C-_'.
5283
5284*** Scoring can be done on words using the new score type `w'.
5285
5286*** Adaptive scoring can be done on a Subject word-by-word basis:
5287
5288 (setq gnus-use-adaptive-scoring '(word))
5289
5290*** Scores can be decayed.
79214ddf 5291
a933dad1
DL
5292 (setq gnus-decay-scores t)
5293
5294*** Scoring can be performed using a regexp on the Date header. The
5295Date is normalized to compact ISO 8601 format first.
5296
5297*** A new command has been added to remove all data on articles from
5298the native server.
5299
5300 `M-x gnus-group-clear-data-on-native-groups'
5301
5302*** A new command for reading collections of documents
5303(nndoc with nnvirtual on top) has been added -- `M-C-d'.
5304
5305*** Process mark sets can be pushed and popped.
5306
5307*** A new mail-to-news backend makes it possible to post
5308even when the NNTP server doesn't allow posting.
5309
5310*** A new backend for reading searches from Web search engines
5311(DejaNews, Alta Vista, InReference) has been added.
5312
5313 Use the `G w' command in the group buffer to create such
5314 a group.
5315
5316*** Groups inside topics can now be sorted using the standard
5317sorting functions, and each topic can be sorted independently.
5318
5319 See the commands under the `T S' submap.
5320
5321*** Subsets of the groups can be sorted independently.
5322
5323 See the commands under the `G P' submap.
5324
5325*** Cached articles can be pulled into the groups.
79214ddf 5326
a933dad1
DL
5327 Use the `Y c' command.
5328
5329*** Score files are now applied in a more reliable order.
5330
5331*** Reports on where mail messages end up can be generated.
5332
5333 `M-x nnmail-split-history'
5334
5335*** More hooks and functions have been added to remove junk
5336from incoming mail before saving the mail.
79214ddf 5337
a933dad1
DL
5338 See `nnmail-prepare-incoming-header-hook'.
5339
5340*** The nnml mail backend now understands compressed article files.
5341
5342*** To enable Gnus to read/post multi-lingual articles, you must execute
5343the following code, for instance, in your .emacs.
5344
5345 (add-hook 'gnus-startup-hook 'gnus-mule-initialize)
5346
5347Then, when you start Gnus, it will decode non-ASCII text automatically
5348and show appropriate characters. (Note: if you are using gnus-mime
5349from the SEMI package, formerly known as TM, you should NOT add this
5350hook to gnus-startup-hook; gnus-mime has its own method of handling
5351this issue.)
5352
5353Since it is impossible to distinguish all coding systems
5354automatically, you may need to specify a choice of coding system for a
5355particular news group. This can be done by:
5356
5357 (gnus-mule-add-group NEWSGROUP 'CODING-SYSTEM)
5358
5359Here NEWSGROUP should be a string which names a newsgroup or a tree
5360of newsgroups. If NEWSGROUP is "XXX.YYY", all news groups under
5361"XXX.YYY" (including "XXX.YYY.ZZZ") will use the specified coding
5362system. CODING-SYSTEM specifies which coding system to use (for both
5363for reading and posting).
5364
5365CODING-SYSTEM can also be a cons cell of the form
5366 (READ-CODING-SYSTEM . POST-CODING-SYSTEM)
5367Then READ-CODING-SYSTEM is used when you read messages from the
5368newsgroups, while POST-CODING-SYSTEM is used when you post messages
5369there.
5370
5371Emacs knows the right coding systems for certain newsgroups by
5372default. Here are some of these default settings:
5373
5374 (gnus-mule-add-group "fj" 'iso-2022-7)
5375 (gnus-mule-add-group "alt.chinese.text" 'hz-gb-2312)
5376 (gnus-mule-add-group "alt.hk" 'hz-gb-2312)
5377 (gnus-mule-add-group "alt.chinese.text.big5" 'cn-big5)
5378 (gnus-mule-add-group "soc.culture.vietnamese" '(nil . viqr))
5379
5380When you reply by mail to an article, these settings are ignored;
5381the mail is encoded according to sendmail-coding-system, as usual.
5382
5383** CC mode changes.
5384
5385*** If you edit primarily one style of C (or C++, Objective-C, Java)
5386code, you may want to make the CC Mode style variables have global
5387values so that you can set them directly in your .emacs file. To do
5388this, set c-style-variables-are-local-p to nil in your .emacs file.
5389Note that this only takes effect if you do it *before* cc-mode.el is
5390loaded.
5391
5392If you typically edit more than one style of C (or C++, Objective-C,
79214ddf 5393Java) code in a single Emacs session, you may want to make the CC Mode
a933dad1 5394style variables have buffer local values. By default, all buffers
79214ddf
FP
5395share the same style variable settings; to make them buffer local, set
5396c-style-variables-are-local-p to t in your .emacs file. Note that you
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5397must do this *before* CC Mode is loaded.
5398
5399*** The new variable c-indentation-style holds the C style name
5400of the current buffer.
5401
5402*** The variable c-block-comments-indent-p has been deleted, because
5403it is no longer necessary. C mode now handles all the supported styles
5404of block comments, with no need to say which one you will use.
5405
5406*** There is a new indentation style "python", which specifies the C
5407style that the Python developers like.
5408
5409*** There is a new c-cleanup-list option: brace-elseif-brace.
5410This says to put ...} else if (...) {... on one line,
5411just as brace-else-brace says to put ...} else {... on one line.
5412
5413** VC Changes [new]
5414
5415** In vc-retrieve-snapshot (C-x v r), if you don't specify a snapshot
5416name, it retrieves the *latest* versions of all files in the current
5417directory and its subdirectories (aside from files already locked).
5418
5419This feature is useful if your RCS directory is a link to a common
5420master directory, and you want to pick up changes made by other
5421developers.
5422
5423You can do the same thing for an individual file by typing C-u C-x C-q
5424RET in a buffer visiting that file.
5425
5426*** VC can now handle files under CVS that are being "watched" by
5427other developers. Such files are made read-only by CVS. To get a
5428writable copy, type C-x C-q in a buffer visiting such a file. VC then
5429calls "cvs edit", which notifies the other developers of it.
5430
5431*** vc-version-diff (C-u C-x v =) now suggests reasonable defaults for
5432version numbers, based on the current state of the file.
5433
5434** Calendar changes.
5435
5436A new function, list-holidays, allows you list holidays or subclasses
5437of holidays for ranges of years. Related menu items allow you do this
5438for the year of the selected date, or the following/previous years.
5439
5440** ps-print changes
5441
79214ddf 5442There are some new user variables for customizing the page layout.
a933dad1
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5443
5444*** Paper size, paper orientation, columns
5445
5446The variable `ps-paper-type' determines the size of paper ps-print
5447formats for; it should contain one of the symbols:
5448`a4' `a3' `letter' `legal' `letter-small' `tabloid'
5449`ledger' `statement' `executive' `a4small' `b4' `b5'
5450It defaults to `letter'.
5451If you need other sizes, see the variable `ps-page-dimensions-database'.
5452
5453The variable `ps-landscape-mode' determines the orientation
79214ddf 5454of the printing on the page. nil, the default, means "portrait" mode,
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5455non-nil means "landscape" mode.
5456
5457The variable `ps-number-of-columns' must be a positive integer.
5458It determines the number of columns both in landscape and portrait mode.
79214ddf 5459It defaults to 1.
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5460
5461*** Horizontal layout
5462
5463The horizontal layout is determined by the variables
5464`ps-left-margin', `ps-inter-column', and `ps-right-margin'.
5465All are measured in points.
5466
5467*** Vertical layout
5468
5469The vertical layout is determined by the variables
5470`ps-bottom-margin', `ps-top-margin', and `ps-header-offset'.
5471All are measured in points.
5472
5473*** Headers
5474
5475If the variable `ps-print-header' is nil, no header is printed. Then
5476`ps-header-offset' is not relevant and `ps-top-margin' represents the
5477margin above the text.
5478
79214ddf 5479If the variable `ps-print-header-frame' is non-nil, a gaudy
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5480framing box is printed around the header.
5481
5482The contents of the header are determined by `ps-header-lines',
5483`ps-show-n-of-n', `ps-left-header' and `ps-right-header'.
5484
79214ddf
FP
5485The height of the header is determined by `ps-header-line-pad',
5486`ps-header-font-family', `ps-header-title-font-size' and
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5487`ps-header-font-size'.
5488
5489*** Font managing
5490
5491The variable `ps-font-family' determines which font family is to be
5492used for ordinary text. Its value must be a key symbol in the alist
5493`ps-font-info-database'. You can add other font families by adding
5494elements to this alist.
5495
79214ddf 5496The variable `ps-font-size' determines the size of the font
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5497for ordinary text. It defaults to 8.5 points.
5498
5499** hideshow changes.
5500
5501*** now supports hiding of blocks of single line comments (like // for
79214ddf 5502C++, ; for lisp).
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5503
5504*** Support for java-mode added.
5505
5506*** When doing `hs-hide-all' it is now possible to also hide the comments
5507in the file if `hs-hide-comments-when-hiding-all' is set.
5508
5509*** The new function `hs-hide-initial-comment' hides the the comments at
5510the beginning of the files. Finally those huge RCS logs don't stay in your
5511way! This is run by default when entering the `hs-minor-mode'.
5512
5513*** Now uses overlays instead of `selective-display', so is more
5514robust and a lot faster.
5515
79214ddf 5516*** A block beginning can span multiple lines.
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5517
5518*** The new variable `hs-show-hidden-short-form' if t, directs hideshow
5519to show only the beginning of a block when it is hidden. See the
5520documentation for more details.
5521
5522** Changes in Enriched mode.
5523
5524*** When you visit a file in enriched-mode, Emacs will make sure it is
5525filled to the current fill-column. This behavior is now independent
5526of the size of the window. When you save the file, the fill-column in
5527use is stored as well, so that the whole buffer need not be refilled
5528the next time unless the fill-column is different.
5529
5530*** use-hard-newlines is now a minor mode. When it is enabled, Emacs
5531distinguishes between hard and soft newlines, and treats hard newlines
5532as paragraph boundaries. Otherwise all newlines inserted are marked
5533as soft, and paragraph boundaries are determined solely from the text.
5534
5535** Font Lock mode
5536
5537*** Custom support
5538
5539The variables font-lock-face-attributes, font-lock-display-type and
5540font-lock-background-mode are now obsolete; the recommended way to specify the
5541faces to use for Font Lock mode is with M-x customize-group on the new custom
5542group font-lock-highlighting-faces. If you set font-lock-face-attributes in
5543your ~/.emacs file, Font Lock mode will respect its value. However, you should
5544consider converting from setting that variable to using M-x customize.
5545
5546You can still use X resources to specify Font Lock face appearances.
5547
5548*** Maximum decoration
5549
5550Fontification now uses the maximum level of decoration supported by
5551default. Previously, fontification used a mode-specific default level
5552of decoration, which is typically the minimum level of decoration
5553supported. You can set font-lock-maximum-decoration to nil
5554to get the old behavior.
5555
5556*** New support
5557
5558Support is now provided for Java, Objective-C, AWK and SIMULA modes.
5559
5560Note that Font Lock mode can be turned on without knowing exactly what modes
5561support Font Lock mode, via the command global-font-lock-mode.
5562
5563*** Configurable support
5564
5565Support for C, C++, Objective-C and Java can be more easily configured for
5566additional types and classes via the new variables c-font-lock-extra-types,
5567c++-font-lock-extra-types, objc-font-lock-extra-types and, you guessed it,
5568java-font-lock-extra-types. These value of each of these variables should be a
5569list of regexps matching the extra type names. For example, the default value
5570of c-font-lock-extra-types is ("\\sw+_t") which means fontification follows the
5571convention that C type names end in _t. This results in slower fontification.
5572
5573Of course, you can change the variables that specify fontification in whatever
5574way you wish, typically by adding regexps. However, these new variables make
5575it easier to make specific and common changes for the fontification of types.
5576
5577*** Adding highlighting patterns to existing support
5578
5579You can use the new function font-lock-add-keywords to add your own
5580highlighting patterns, such as for project-local or user-specific constructs,
5581for any mode.
5582
5583For example, to highlight `FIXME:' words in C comments, put:
5584
5585 (font-lock-add-keywords 'c-mode '(("\\<FIXME:" 0 font-lock-warning-face t)))
5586
5587in your ~/.emacs.
5588
5589*** New faces
5590
5591Font Lock now defines two new faces, font-lock-builtin-face and
5592font-lock-warning-face. These are intended to highlight builtin keywords,
5593distinct from a language's normal keywords, and objects that should be brought
5594to user attention, respectively. Various modes now use these new faces.
5595
5596*** Changes to fast-lock support mode
5597
5598The fast-lock package, one of the two Font Lock support modes, can now process
5599cache files silently. You can use the new variable fast-lock-verbose, in the
5600same way as font-lock-verbose, to control this feature.
5601
5602*** Changes to lazy-lock support mode
5603
5604The lazy-lock package, one of the two Font Lock support modes, can now fontify
5605according to the true syntactic context relative to other lines. You can use
5606the new variable lazy-lock-defer-contextually to control this feature. If
5607non-nil, changes to the buffer will cause subsequent lines in the buffer to be
5608refontified after lazy-lock-defer-time seconds of idle time. If nil, then only
5609the modified lines will be refontified; this is the same as the previous Lazy
5610Lock mode behaviour and the behaviour of Font Lock mode.
5611
5612This feature is useful in modes where strings or comments can span lines.
5613For example, if a string or comment terminating character is deleted, then if
5614this feature is enabled subsequent lines in the buffer will be correctly
5615refontified to reflect their new syntactic context. Previously, only the line
5616containing the deleted character would be refontified and you would have to use
5617the command M-g M-g (font-lock-fontify-block) to refontify some lines.
5618
5619As a consequence of this new feature, two other variables have changed:
5620
5621Variable `lazy-lock-defer-driven' is renamed `lazy-lock-defer-on-scrolling'.
5622Variable `lazy-lock-defer-time' can now only be a time, i.e., a number.
5623Buffer modes for which on-the-fly deferral applies can be specified via the
5624new variable `lazy-lock-defer-on-the-fly'.
5625
5626If you set these variables in your ~/.emacs, then you may have to change those
5627settings.
5628
5629** Ada mode changes.
5630
5631*** There is now better support for using find-file.el with Ada mode.
5632If you switch between spec and body, the cursor stays in the same
5633procedure (modulo overloading). If a spec has no body file yet, but
5634you try to switch to its body file, Ada mode now generates procedure
5635stubs.
5636
5637*** There are two new commands:
5638 - `ada-make-local' : invokes gnatmake on the current buffer
5639 - `ada-check-syntax' : check syntax of current buffer.
5640
5641The user options `ada-compiler-make', `ada-make-options',
5642`ada-language-version', `ada-compiler-syntax-check', and
79214ddf 5643`ada-compile-options' are used within these commands.
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5644
5645*** Ada mode can now work with Outline minor mode. The outline level
5646is calculated from the indenting, not from syntactic constructs.
5647Outlining does not work if your code is not correctly indented.
5648
5649*** The new function `ada-gnat-style' converts the buffer to the style of
5650formatting used in GNAT. It places two blanks after a comment start,
5651places one blank between a word end and an opening '(', and puts one
5652space between a comma and the beginning of a word.
5653
5654** Scheme mode changes.
5655
5656*** Scheme mode indentation now uses many of the facilities of Lisp
5657mode; therefore, the variables to customize it are the variables used
5658for Lisp mode which have names starting with `lisp-'. The variables
5659with names starting with `scheme-' which used to do this no longer
5660have any effect.
5661
5662If you want to use different indentation for Scheme and Lisp, this is
5663still possible, but now you must do it by adding a hook to
5664scheme-mode-hook, which could work by setting the `lisp-' indentation
5665variables as buffer-local variables.
5666
5667*** DSSSL mode is a variant of Scheme mode, for editing DSSSL scripts.
5668Use M-x dsssl-mode.
5669
133c9e59
GM
5670** Changes to the emacsclient program
5671
875c1439
GM
5672*** If a socket can't be found, and environment variables LOGNAME or
5673USER are set, emacsclient now looks for a socket based on the UID
5674associated with the name. That is an emacsclient running as root
5675can connect to an Emacs server started by a non-root user.
5676
133c9e59 5677*** The emacsclient program now accepts an option --no-wait which tells
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5678it to return immediately without waiting for you to "finish" the
5679buffer in Emacs.
5680
133c9e59
GM
5681*** The new option --alternate-editor allows to specify an editor to
5682use if Emacs is not running. The environment variable
5683ALTERNATE_EDITOR can be used for the same effect; the command line
5684option takes precedence.
5685
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5686** M-x eldoc-mode enables a minor mode in which the echo area
5687constantly shows the parameter list for function being called at point
5688(in Emacs Lisp and Lisp Interaction modes only).
5689
5690** C-x n d now runs the new command narrow-to-defun,
5691which narrows the accessible parts of the buffer to just
5692the current defun.
5693
5694** Emacs now handles the `--' argument in the standard way; all
5695following arguments are treated as ordinary file names.
5696
5697** On MSDOS and Windows, the bookmark file is now called _emacs.bmk,
5698and the saved desktop file is now called _emacs.desktop (truncated if
5699necessary).
5700
5701** When you kill a buffer that visits a file,
5702if there are any registers that save positions in the file,
5703these register values no longer become completely useless.
5704If you try to go to such a register with C-x j, then you are
5705asked whether to visit the file again. If you say yes,
5706it visits the file and then goes to the same position.
5707
5708** When you visit a file that changes frequently outside Emacs--for
5709example, a log of output from a process that continues to run--it may
5710be useful for Emacs to revert the file without querying you whenever
5711you visit the file afresh with C-x C-f.
5712
5713You can request this behavior for certain files by setting the
5714variable revert-without-query to a list of regular expressions. If a
5715file's name matches any of these regular expressions, find-file and
5716revert-buffer revert the buffer without asking for permission--but
5717only if you have not edited the buffer text yourself.
5718
5719** set-default-font has been renamed to set-frame-font
5720since it applies only to the current frame.
5721
5722** In TeX mode, you can use the variable tex-main-file to specify the
5723file for tex-file to run TeX on. (By default, tex-main-file is nil,
5724and tex-file runs TeX on the current visited file.)
5725
5726This is useful when you are editing a document that consists of
5727multiple files. In each of the included files, you can set up a local
5728variable list which specifies the top-level file of your document for
5729tex-main-file. Then tex-file will run TeX on the whole document
5730instead of just the file you are editing.
5731
5732** RefTeX mode
5733
5734RefTeX mode is a new minor mode with special support for \label, \ref
5735and \cite macros in LaTeX documents. RefTeX distinguishes labels of
5736different environments (equation, figure, ...) and has full support for
5737multifile documents. To use it, select a buffer with a LaTeX document and
5738turn the mode on with M-x reftex-mode. Here are the main user commands:
5739
79214ddf 5740C-c ( reftex-label
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5741 Creates a label semi-automatically. RefTeX is context sensitive and
5742 knows which kind of label is needed.
5743
5744C-c ) reftex-reference
5745 Offers in a menu all labels in the document, along with context of the
5746 label definition. The selected label is referenced as \ref{LABEL}.
5747
5748C-c [ reftex-citation
5749 Prompts for a regular expression and displays a list of matching BibTeX
5750 database entries. The selected entry is cited with a \cite{KEY} macro.
5751
5752C-c & reftex-view-crossref
5753 Views the cross reference of a \ref or \cite command near point.
5754
5755C-c = reftex-toc
5756 Shows a table of contents of the (multifile) document. From there you
5757 can quickly jump to every section.
79214ddf 5758
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5759Under X, RefTeX installs a "Ref" menu in the menu bar, with additional
5760commands. Press `?' to get help when a prompt mentions this feature.
5761Full documentation and customization examples are in the file
5762reftex.el. You can use the finder to view the file documentation:
5763C-h p --> tex --> reftex.el
5764
5765** Changes in BibTeX mode.
5766
5767*** Info documentation is now available.
5768
5769*** Don't allow parentheses in string constants anymore. This confused
5770both the BibTeX program and Emacs BibTeX mode.
5771
5772*** Renamed variable bibtex-mode-user-optional-fields to
5773bibtex-user-optional-fields.
5774
5775*** Removed variable bibtex-include-OPTannote
5776(use bibtex-user-optional-fields instead).
5777
5778*** New interactive functions to copy and kill fields and complete
5779entries to the BibTeX kill ring, from where they can be yanked back by
5780appropriate functions.
5781
5782*** New interactive functions for repositioning and marking of
5783entries. They are bound by default to M-C-l and M-C-h.
5784
5785*** New hook bibtex-clean-entry-hook. It is called after entry has
5786been cleaned.
5787
5788*** New variable bibtex-field-delimiters, which replaces variables
5789bibtex-field-{left|right}-delimiter.
5790
5791*** New variable bibtex-entry-delimiters to determine how entries
5792shall be delimited.
5793
5794*** Allow preinitialization of fields. See documentation of
5795bibtex-user-optional-fields, bibtex-entry-field-alist, and
5796bibtex-include-OPTkey for details.
5797
5798*** Book and InBook entries require either an author or an editor
5799field. This is now supported by bibtex.el. Alternative fields are
5800prefixed with `ALT'.
5801
5802*** New variable bibtex-entry-format, which replaces variable
5803bibtex-clean-entry-zap-empty-opts and allows specification of many
5804formatting options performed on cleaning an entry (see variable
5805documentation).
5806
5807*** Even more control on how automatic keys are generated. See
5808documentation of bibtex-generate-autokey for details. Transcriptions
5809for foreign languages other than German are now handled, too.
5810
5811*** New boolean user option bibtex-comma-after-last-field to decide if
5812comma should be inserted at end of last field.
5813
5814*** New boolean user option bibtex-align-at-equal-sign to determine if
5815alignment should be made at left side of field contents or at equal
5816signs. New user options to control entry layout (e.g. indentation).
5817
5818*** New function bibtex-fill-entry to realign entries.
5819
5820*** New function bibtex-reformat to reformat region or buffer.
5821
5822*** New function bibtex-convert-alien to convert a BibTeX database
5823from alien sources.
5824
5825*** New function bibtex-complete-key (similar to bibtex-complete-string)
5826to complete prefix to a key defined in buffer. Mainly useful in
5827crossref entries.
5828
5829*** New function bibtex-count-entries to count entries in buffer or
5830region.
5831
5832*** Added support for imenu.
5833
5834*** The function `bibtex-validate' now checks current region instead
5835of buffer if mark is active. Now it shows all errors of buffer in a
5836`compilation mode' buffer. You can use the normal commands (e.g.
5837`next-error') for compilation modes to jump to errors.
5838
5839*** New variable `bibtex-string-file-path' to determine where the files
5840from `bibtex-string-files' are searched.
5841
5842** Iso Accents mode now supports Latin-3 as an alternative.
5843
30a009a5 5844** The command next-error now opens blocks hidden by hideshow.
047f434a 5845
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5846** The function using-unix-filesystems has been replaced by the
5847functions add-untranslated-filesystem and remove-untranslated-filesystem.
5848Each of these functions takes the name of a drive letter or directory
5849as an argument.
5850
5851When a filesystem is added as untranslated, all files on it are read
5852and written in binary mode (no cr/lf translation is performed).
5853
5854** browse-url changes
5855
5856*** New methods for: Grail (browse-url-generic), MMM (browse-url-mmm),
5857Lynx in a separate xterm (browse-url-lynx-xterm) or in an Emacs window
5858(browse-url-lynx-emacs), remote W3 (browse-url-w3-gnudoit), generic
5859non-remote-controlled browsers (browse-url-generic) and associated
5860customization variables.
5861
5862*** New commands `browse-url-of-region' and `browse-url'.
5863
5864*** URLs marked up with <URL:...> (RFC1738) work if broken across
5865lines. Browsing methods can be associated with URL regexps
5866(e.g. mailto: URLs) via `browse-url-browser-function'.
5867
5868** Changes in Ediff
5869
5870*** Clicking Mouse-2 on a brief command description in Ediff control panel
5871pops up the Info file for this command.
5872
5873*** There is now a variable, ediff-autostore-merges, which controls whether
5874the result of a merge is saved in a file. By default, this is done only when
5875merge is done from a session group (eg, when merging files in two different
5876directories).
5877
5878*** Since Emacs 19.31 (this hasn't been announced before), Ediff can compare
5879and merge groups of files residing in different directories, or revisions of
5880files in the same directory.
5881
5882*** Since Emacs 19.31, Ediff can apply multi-file patches interactively.
5883The patches must be in the context format or GNU unified format. (The bug
5884related to the GNU format has now been fixed.)
5885
5886** Changes in Viper
5887
5888*** The startup file is now .viper instead of .vip
79214ddf 5889*** All variable/function names have been changed to start with viper-
a933dad1
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5890 instead of vip-.
5891*** C-\ now simulates the meta-key in all Viper states.
79214ddf 5892*** C-z in Insert state now escapes to Vi for the duration of the next
a933dad1
DL
5893Viper command. In Vi and Insert states, C-z behaves as before.
5894*** C-c \ escapes to Vi for one command if Viper is in Insert or Emacs states.
5895*** _ is no longer the meta-key in Vi state.
5896*** The variable viper-insert-state-cursor-color can be used to change cursor
5897color when Viper is in insert state.
5898*** If search lands the cursor near the top or the bottom of the window,
5899Viper pulls the window up or down to expose more context. The variable
5900viper-adjust-window-after-search controls this behavior.
5901
5902** Etags changes.
5903
5904*** In C, C++, Objective C and Java, Etags tags global variables by
5905default. The resulting tags files are inflated by 30% on average.
5906Use --no-globals to turn this feature off. Etags can also tag
5907variables which are members of structure-like constructs, but it does
5908not by default. Use --members to turn this feature on.
5909
5910*** C++ member functions are now recognized as tags.
5911
5912*** Java is tagged like C++. In addition, "extends" and "implements"
5913constructs are tagged. Files are recognised by the extension .java.
5914
5915*** Etags can now handle programs written in Postscript. Files are
5916recognised by the extensions .ps and .pdb (Postscript with C syntax).
5917In Postscript, tags are lines that start with a slash.
5918
5919*** Etags now handles Objective C and Objective C++ code. The usual C and
5920C++ tags are recognized in these languages; in addition, etags
5921recognizes special Objective C syntax for classes, class categories,
5922methods and protocols.
5923
5924*** Etags also handles Cobol. Files are recognised by the extension
5925.cobol. The tagged lines are those containing a word that begins in
5926column 8 and ends in a full stop, i.e. anything that could be a
5927paragraph name.
5928
5929*** Regexps in Etags now support intervals, as in ed or grep. The syntax of
5930an interval is \{M,N\}, and it means to match the preceding expression
5931at least M times and as many as N times.
5932
5933** The format for specifying a custom format for time-stamp to insert
5934in files has changed slightly.
5935
5936With the new enhancements to the functionality of format-time-string,
5937time-stamp-format will change to be eventually compatible with it.
5938This conversion is being done in two steps to maintain compatibility
5939with old time-stamp-format values.
5940
5941In the new scheme, alternate case is signified by the number-sign
5942(`#') modifier, rather than changing the case of the format character.
5943This feature is as yet incompletely implemented for compatibility
5944reasons.
5945
5946In the old time-stamp-format, all numeric fields defaulted to their
5947natural width. (With format-time-string, each format has a
5948fixed-width default.) In this version, you can specify the colon
5949(`:') modifier to a numeric conversion to mean "give me the historical
5950time-stamp-format width default." Do not use colon if you are
5951specifying an explicit width, as in "%02d".
5952
5953Numbers are no longer truncated to the requested width, except in the
5954case of "%02y", which continues to give a two-digit year. Digit
5955truncation probably wasn't being used for anything else anyway.
5956
5957The new formats will work with old versions of Emacs. New formats are
5958being recommended now to allow time-stamp-format to change in the
5959future to be compatible with format-time-string. The new forms being
5960recommended now will continue to work then.
5961
5962See the documentation string for the variable time-stamp-format for
5963details.
5964
5965** There are some additional major modes:
5966
5967dcl-mode, for editing VMS DCL files.
5968m4-mode, for editing files of m4 input.
5969meta-mode, for editing MetaFont and MetaPost source files.
5970
5971** In Shell mode, the command shell-copy-environment-variable lets you
5972copy the value of a specified environment variable from the subshell
5973into Emacs.
5974
5975** New Lisp packages include:
5976
5977*** battery.el displays battery status for laptops.
5978
5979*** M-x bruce (named after Lenny Bruce) is a program that might
5980be used for adding some indecent words to your email.
5981
5982*** M-x crisp-mode enables an emulation for the CRiSP editor.
5983
5984*** M-x dirtrack arranges for better tracking of directory changes
5985in shell buffers.
5986
5987*** The new library elint.el provides for linting of Emacs Lisp code.
5988See the documentation for `elint-initialize', `elint-current-buffer'
5989and `elint-defun'.
5990
5991*** M-x expand-add-abbrevs defines a special kind of abbrev which is
5992meant for programming constructs. These abbrevs expand like ordinary
5993ones, when you type SPC, but only at the end of a line and not within
5994strings or comments.
5995
5996These abbrevs can act as templates: you can define places within an
5997abbrev for insertion of additional text. Once you expand the abbrev,
5998you can then use C-x a p and C-x a n to move back and forth to these
5999insertion points. Thus you can conveniently insert additional text
6000at these points.
6001
6002*** filecache.el remembers the location of files so that you
6003can visit them by short forms of their names.
6004
6005*** find-func.el lets you find the definition of the user-loaded
6006Emacs Lisp function at point.
6007
6008*** M-x handwrite converts text to a "handwritten" picture.
6009
6010*** M-x iswitchb-buffer is a command for switching to a buffer, much like
6011switch-buffer, but it reads the argument in a more helpful way.
6012
6013*** M-x landmark implements a neural network for landmark learning.
6014
6015*** M-x locate provides a convenient interface to the `locate' program.
6016
6017*** M4 mode is a new mode for editing files of m4 input.
6018
6019*** mantemp.el creates C++ manual template instantiations
6020from the GCC error messages which indicate which instantiations are needed.
6021
6022*** mouse-copy.el provides a one-click copy and move feature.
6023You can drag a region with M-mouse-1, and it is automatically
6024inserted at point. M-Shift-mouse-1 deletes the text from its
6025original place after inserting the copy.
6026
6027*** mouse-drag.el lets you do scrolling by dragging Mouse-2
6028on the buffer.
6029
6030You click the mouse and move; that distance either translates into the
6031velocity to scroll (with mouse-drag-throw) or the distance to scroll
6032(with mouse-drag-drag). Horizontal scrolling is enabled when needed.
6033
6034Enable mouse-drag with:
6035 (global-set-key [down-mouse-2] 'mouse-drag-throw)
6036-or-
6037 (global-set-key [down-mouse-2] 'mouse-drag-drag)
6038
6039*** mspools.el is useful for determining which mail folders have
6040mail waiting to be read in them. It works with procmail.
6041
6042*** Octave mode is a major mode for editing files of input for Octave.
6043It comes with a facility for communicating with an Octave subprocess.
6044
6045*** ogonek
6046
6047The ogonek package provides functions for changing the coding of
6048Polish diacritic characters in buffers. Codings known from various
6049platforms are supported such as ISO8859-2, Mazovia, IBM Latin2, and
6050TeX. For example, you can change the coding from Mazovia to
6051ISO8859-2. Another example is a change of coding from ISO8859-2 to
6052prefix notation (in which `/a' stands for the aogonek character, for
6053instance) and vice versa.
6054
6055To use this package load it using
6056 M-x load-library [enter] ogonek
6057Then, you may get an explanation by calling one of
79214ddf 6058 M-x ogonek-jak -- in Polish
a933dad1
DL
6059 M-x ogonek-how -- in English
6060The info specifies the commands and variables provided as well as the
6061ways of customization in `.emacs'.
6062
6063*** Interface to ph.
6064
6065Emacs provides a client interface to CCSO Nameservers (ph/qi)
6066
6067The CCSO nameserver is used in many universities to provide directory
6068services about people. ph.el provides a convenient Emacs interface to
6069these servers.
6070
6071*** uce.el is useful for replying to unsolicited commercial email.
6072
6073*** vcursor.el implements a "virtual cursor" feature.
6074You can move the virtual cursor with special commands
6075while the real cursor does not move.
6076
6077*** webjump.el is a "hot list" package which you can set up
6078for visiting your favorite web sites.
6079
6080*** M-x winner-mode is a minor mode which saves window configurations,
6081so you can move back to other configurations that you have recently used.
6082
6083** movemail change
6084
6085Movemail no longer needs to be installed setuid root in order for POP
6086mail retrieval to function properly. This is because it no longer
6087supports the RPOP (reserved-port POP) protocol; instead, it uses the
6088user's POP password to authenticate to the mail server.
6089
6090This change was made earlier, but not reported in NEWS before.
6091\f
6092* Emacs 20.1 changes for MS-DOS and MS-Windows.
6093
6094** Changes in handling MS-DOS/MS-Windows text files.
6095
6096Emacs handles three different conventions for representing
6097end-of-line: CRLF for MSDOS, LF for Unix and GNU, and CR (used on the
6098Macintosh). Emacs determines which convention is used in a specific
6099file based on the contents of that file (except for certain special
6100file names), and when it saves the file, it uses the same convention.
6101
6102To save the file and change the end-of-line convention, you can use
6103C-x RET f (set-buffer-file-coding-system) to specify a different
6104coding system for the buffer. Then, when you save the file, the newly
6105specified coding system will take effect. For example, to save with
6106LF, specify undecided-unix (or some other ...-unix coding system); to
6107save with CRLF, specify undecided-dos.
6108\f
6109* Lisp Changes in Emacs 20.1
6110
6111** Byte-compiled files made with Emacs 20 will, in general, work in
6112Emacs 19 as well, as long as the source code runs in Emacs 19. And
6113vice versa: byte-compiled files made with Emacs 19 should also run in
6114Emacs 20, as long as the program itself works in Emacs 20.
6115
6116** Windows-specific functions and variables have been renamed
6117to start with w32- instead of win32-.
6118
6119In hacker language, calling something a "win" is a form of praise. We
6120don't want to praise a non-free Microsoft system, so we don't call it
6121"win".
6122
6123** Basic Lisp changes
6124
6125*** A symbol whose name starts with a colon now automatically
6126evaluates to itself. Therefore such a symbol can be used as a constant.
6127
6128*** The defined purpose of `defconst' has been changed. It should now
6129be used only for values that should not be changed whether by a program
6130or by the user.
6131
6132The actual behavior of defconst has not been changed.
6133
6134*** There are new macros `when' and `unless'
6135
6136(when CONDITION BODY...) is short for (if CONDITION (progn BODY...))
6137(unless CONDITION BODY...) is short for (if CONDITION nil BODY...)
6138
6139*** Emacs now defines functions caar, cadr, cdar and cddr with their
6140usual Lisp meanings. For example, caar returns the car of the car of
6141its argument.
6142
6143*** equal, when comparing strings, now ignores their text properties.
6144
6145*** The new function `functionp' tests whether an object is a function.
6146
6147*** arrayp now returns t for char-tables and bool-vectors.
6148
6149*** Certain primitives which use characters (as integers) now get an
6150error if the integer is not a valid character code. These primitives
6151include insert-char, char-to-string, and the %c construct in the
6152`format' function.
6153
6154*** The `require' function now insists on adding a suffix, either .el
6155or .elc, to the file name. Thus, (require 'foo) will not use a file
6156whose name is just foo. It insists on foo.el or foo.elc.
6157
6158*** The `autoload' function, when the file name does not contain
6159either a directory name or the suffix .el or .elc, insists on
6160adding one of these suffixes.
6161
6162*** string-to-number now takes an optional second argument BASE
6163which specifies the base to use when converting an integer.
79214ddf 6164If BASE is omitted, base 10 is used.
a933dad1
DL
6165
6166We have not implemented other radices for floating point numbers,
6167because that would be much more work and does not seem useful.
6168
6169*** substring now handles vectors as well as strings.
6170
6171*** The Common Lisp function eql is no longer defined normally.
6172You must load the `cl' library to define it.
6173
6174*** The new macro `with-current-buffer' lets you evaluate an expression
6175conveniently with a different current buffer. It looks like this:
6176
6177 (with-current-buffer BUFFER BODY-FORMS...)
6178
6179BUFFER is the expression that says which buffer to use.
6180BODY-FORMS say what to do in that buffer.
6181
6182*** The new primitive `save-current-buffer' saves and restores the
6183choice of current buffer, like `save-excursion', but without saving or
6184restoring the value of point or the mark. `with-current-buffer'
6185works using `save-current-buffer'.
6186
6187*** The new macro `with-temp-file' lets you do some work in a new buffer and
6188write the output to a specified file. Like `progn', it returns the value
6189of the last form.
6190
6191*** The new macro `with-temp-buffer' lets you do some work in a new buffer,
6192which is discarded after use. Like `progn', it returns the value of the
6193last form. If you wish to return the buffer contents, use (buffer-string)
6194as the last form.
6195
6196*** The new function split-string takes a string, splits it at certain
6197characters, and returns a list of the substrings in between the
6198matches.
6199
6200For example, (split-string "foo bar lose" " +") returns ("foo" "bar" "lose").
6201
6202*** The new macro with-output-to-string executes some Lisp expressions
6203with standard-output set up so that all output feeds into a string.
6204Then it returns that string.
6205
6206For example, if the current buffer name is `foo',
6207
6208(with-output-to-string
6209 (princ "The buffer is ")
6210 (princ (buffer-name)))
6211
6212returns "The buffer is foo".
6213
6214** Non-ASCII characters are now supported, if enable-multibyte-characters
6215is non-nil.
6216
6217These characters have character codes above 256. When inserted in the
6218buffer or stored in a string, they are represented as multibyte
6219characters that occupy several buffer positions each.
6220
6221*** When enable-multibyte-characters is non-nil, a single character in
6222a buffer or string can be two or more bytes (as many as four).
6223
6224Buffers and strings are still made up of unibyte elements;
6225character positions and string indices are always measured in bytes.
6226Therefore, moving forward one character can increase the buffer
6227position by 2, 3 or 4. The function forward-char moves by whole
6228characters, and therefore is no longer equivalent to
6229 (lambda (n) (goto-char (+ (point) n))).
6230
6231ASCII characters (codes 0 through 127) are still single bytes, always.
6232Sequences of byte values 128 through 255 are used to represent
6233non-ASCII characters. These sequences are called "multibyte
6234characters".
6235
6236The first byte of a multibyte character is always in the range 128
6237through 159 (octal 0200 through 0237). These values are called
6238"leading codes". The second and subsequent bytes are always in the
6239range 160 through 255 (octal 0240 through 0377). The first byte, the
6240leading code, determines how many bytes long the sequence is.
6241
6242*** The function forward-char moves over characters, and therefore
6243(forward-char 1) may increase point by more than 1 if it moves over a
6244multibyte character. Likewise, delete-char always deletes a
6245character, which may be more than one buffer position.
6246
6247This means that some Lisp programs, which assume that a character is
6248always one buffer position, need to be changed.
6249
6250However, all ASCII characters are always one buffer position.
79214ddf 6251
a933dad1
DL
6252*** The regexp [\200-\377] no longer matches all non-ASCII characters,
6253because when enable-multibyte-characters is non-nil, these characters
6254have codes that are not in the range octal 200 to octal 377. However,
6255the regexp [^\000-\177] does match all non-ASCII characters,
6256guaranteed.
6257
6258*** The function char-boundary-p returns non-nil if position POS is
6259between two characters in the buffer (not in the middle of a
6260character).
6261
6262When the value is non-nil, it says what kind of character follows POS:
6263
6264 0 if POS is at an ASCII character or at the end of range,
6265 1 if POS is before a 2-byte length multi-byte form,
6266 2 if POS is at a head of 3-byte length multi-byte form,
6267 3 if POS is at a head of 4-byte length multi-byte form,
6268 4 if POS is at a head of multi-byte form of a composite character.
6269
6270*** The function char-bytes returns how many bytes the character CHAR uses.
6271
6272*** Strings can contain multibyte characters. The function
6273`length' returns the string length counting bytes, which may be
6274more than the number of characters.
6275
6276You can include a multibyte character in a string constant by writing
6277it literally. You can also represent it with a hex escape,
6278\xNNNNNNN..., using as many digits as necessary. Any character which
6279is not a valid hex digit terminates this construct. If you want to
6280follow it with a character that is a hex digit, write backslash and
6281newline in between; that will terminate the hex escape.
6282
6283*** The function concat-chars takes arguments which are characters
6284and returns a string containing those characters.
6285
6286*** The function sref access a multibyte character in a string.
6287(sref STRING INDX) returns the character in STRING at INDEX. INDEX
6288counts from zero. If INDEX is at a position in the middle of a
6289character, sref signals an error.
6290
6291*** The function chars-in-string returns the number of characters
6292in a string. This is less than the length of the string, if the
6293string contains multibyte characters (the length counts bytes).
6294
6295*** The function chars-in-region returns the number of characters
6296in a region from BEG to END. This is less than (- END BEG) if the
6297region contains multibyte characters (the length counts bytes).
6298
6299*** The function string-to-list converts a string to a list of
6300the characters in it. string-to-vector converts a string
6301to a vector of the characters in it.
6302
6303*** The function store-substring alters part of the contents
6304of a string. You call it as follows:
6305
6306 (store-substring STRING IDX OBJ)
6307
6308This says to alter STRING, by storing OBJ starting at index IDX in
6309STRING. OBJ may be either a character or a (smaller) string.
6310This function really does alter the contents of STRING.
6311Since it is impossible to change the length of an existing string,
6312it is an error if OBJ doesn't fit within STRING's actual length.
6313
6314*** char-width returns the width (in columns) of the character CHAR,
6315if it were displayed in the current buffer and the selected window.
6316
6317*** string-width returns the width (in columns) of the text in STRING,
6318if it were displayed in the current buffer and the selected window.
6319
6320*** truncate-string-to-width shortens a string, if necessary,
6321to fit within a certain number of columns. (Of course, it does
6322not alter the string that you give it; it returns a new string
6323which contains all or just part of the existing string.)
6324
6325(truncate-string-to-width STR END-COLUMN &optional START-COLUMN PADDING)
6326
6327This returns the part of STR up to column END-COLUMN.
6328
6329The optional argument START-COLUMN specifies the starting column.
6330If this is non-nil, then the first START-COLUMN columns of the string
6331are not included in the resulting value.
6332
6333The optional argument PADDING, if non-nil, is a padding character to be added
6334at the beginning and end the resulting string, to extend it to exactly
6335WIDTH columns. If PADDING is nil, that means do not pad; then, if STRING
6336is narrower than WIDTH, the value is equal to STRING.
6337
6338If PADDING and START-COLUMN are both non-nil, and if there is no clean
6339place in STRING that corresponds to START-COLUMN (because one
6340character extends across that column), then the padding character
6341PADDING is added one or more times at the beginning of the result
6342string, so that its columns line up as if it really did start at
6343column START-COLUMN.
6344
6345*** When the functions in the list after-change-functions are called,
6346the third argument is the number of bytes in the pre-change text, not
6347necessarily the number of characters. It is, in effect, the
6348difference in buffer position between the beginning and the end of the
6349changed text, before the change.
6350
6351*** The characters Emacs uses are classified in various character
6352sets, each of which has a name which is a symbol. In general there is
6353one character set for each script, not for each language.
6354
6355**** The function charsetp tests whether an object is a character set name.
6356
6357**** The variable charset-list holds a list of character set names.
6358
6359**** char-charset, given a character code, returns the name of the character
6360set that the character belongs to. (The value is a symbol.)
6361
6362**** split-char, given a character code, returns a list containing the
6363name of the character set, followed by one or two byte-values
6364which identify the character within that character set.
6365
6366**** make-char, given a character set name and one or two subsequent
6367byte-values, constructs a character code. This is roughly the
6368opposite of split-char.
6369
6370**** find-charset-region returns a list of the character sets
6371of all the characters between BEG and END.
6372
6373**** find-charset-string returns a list of the character sets
6374of all the characters in a string.
6375
6376*** Here are the Lisp facilities for working with coding systems
6377and specifying coding systems.
6378
6379**** The function coding-system-list returns a list of all coding
6380system names (symbols). With optional argument t, it returns a list
6381of all distinct base coding systems, not including variants.
6382(Variant coding systems are those like latin-1-dos, latin-1-unix
6383and latin-1-mac which specify the end-of-line conversion as well
6384as what to do about code conversion.)
6385
6386**** coding-system-p tests a symbol to see if it is a coding system
6387name. It returns t if so, nil if not.
6388
6389**** file-coding-system-alist specifies which coding systems to use
6390for certain file names. It works like network-coding-system-alist,
6391except that the PATTERN is matched against the file name.
6392
6393Each element has the format (PATTERN . VAL), where PATTERN determines
6394which file names the element applies to. PATTERN should be a regexp
6395to match against a file name.
6396
6397VAL is a coding system, a cons cell containing two coding systems, or
6398a function symbol. If VAL is a coding system, it is used for both
6399decoding what received from the network stream and encoding what sent
6400to the network stream. If VAL is a cons cell containing two coding
6401systems, the car specifies the coding system for decoding, and the cdr
6402specifies the coding system for encoding.
6403
6404If VAL is a function symbol, the function must return a coding system
6405or a cons cell containing two coding systems, which is used as above.
6406
6407**** The variable network-coding-system-alist specifies
6408the coding system to use for network sockets.
6409
6410Each element has the format (PATTERN . VAL), where PATTERN determines
6411which network sockets the element applies to. PATTERN should be
6412either a port number or a regular expression matching some network
6413service names.
6414
6415VAL is a coding system, a cons cell containing two coding systems, or
6416a function symbol. If VAL is a coding system, it is used for both
6417decoding what received from the network stream and encoding what sent
6418to the network stream. If VAL is a cons cell containing two coding
6419systems, the car specifies the coding system for decoding, and the cdr
6420specifies the coding system for encoding.
6421
6422If VAL is a function symbol, the function must return a coding system
6423or a cons cell containing two coding systems, which is used as above.
6424
6425**** process-coding-system-alist specifies which coding systems to use
6426for certain subprocess. It works like network-coding-system-alist,
6427except that the PATTERN is matched against the program name used to
6428start the subprocess.
6429
6430**** The variable default-process-coding-system specifies the coding
6431systems to use for subprocess (and net connection) input and output,
6432when nothing else specifies what to do. The value is a cons cell
6433(OUTPUT-CODING . INPUT-CODING). OUTPUT-CODING applies to output
6434to the subprocess, and INPUT-CODING applies to input from it.
6435
6436**** The variable coding-system-for-write, if non-nil, specifies the
6437coding system to use for writing a file, or for output to a synchronous
6438subprocess.
6439
6440It also applies to any asynchronous subprocess or network connection,
6441but in a different way: the value of coding-system-for-write when you
6442start the subprocess or connection affects that subprocess or
6443connection permanently or until overridden.
6444
6445The variable coding-system-for-write takes precedence over
6446file-coding-system-alist, process-coding-system-alist and
6447network-coding-system-alist, and all other methods of specifying a
6448coding system for output. But most of the time this variable is nil.
6449It exists so that Lisp programs can bind it to a specific coding
6450system for one operation at a time.
6451
6452**** coding-system-for-read applies similarly to input from
6453files, subprocesses or network connections.
6454
6455**** The function process-coding-system tells you what
6456coding systems(s) an existing subprocess is using.
6457The value is a cons cell,
6458 (DECODING-CODING-SYSTEM . ENCODING-CODING-SYSTEM)
6459where DECODING-CODING-SYSTEM is used for decoding output from
6460the subprocess, and ENCODING-CODING-SYSTEM is used for encoding
6461input to the subprocess.
6462
6463**** The function set-process-coding-system can be used to
6464change the coding systems in use for an existing subprocess.
6465
6466** Emacs has a new facility to help users manage the many
6467customization options. To make a Lisp program work with this facility,
6468you need to use the new macros defgroup and defcustom.
6469
6470You use defcustom instead of defvar, for defining a user option
6471variable. The difference is that you specify two additional pieces of
6472information (usually): the "type" which says what values are
6473legitimate, and the "group" which specifies the hierarchy for
6474customization.
6475
6476Thus, instead of writing
6477
6478 (defvar foo-blurgoze nil
6479 "*Non-nil means that foo will act very blurgozely.")
6480
6481you would now write this:
6482
6483 (defcustom foo-blurgoze nil
6484 "*Non-nil means that foo will act very blurgozely."
6485 :type 'boolean
6486 :group foo)
6487
6488The type `boolean' means that this variable has only
6489two meaningful states: nil and non-nil. Other type values
6490describe other possibilities; see the manual for Custom
6491for a description of them.
6492
6493The "group" argument is used to specify a group which the option
6494should belong to. You define a new group like this:
6495
6496 (defgroup ispell nil
6497 "Spell checking using Ispell."
6498 :group 'processes)
6499
6500The "group" argument in defgroup specifies the parent group. The root
6501group is called `emacs'; it should not contain any variables itself,
6502but only other groups. The immediate subgroups of `emacs' correspond
6503to the keywords used by C-h p. Under these subgroups come
6504second-level subgroups that belong to individual packages.
6505
6506Each Emacs package should have its own set of groups. A simple
6507package should have just one group; a more complex package should
6508have a hierarchy of its own groups. The sole or root group of a
6509package should be a subgroup of one or more of the "keyword"
6510first-level subgroups.
6511
6512** New `widget' library for inserting UI components in buffers.
6513
6514This library, used by the new custom library, is documented in a
6515separate manual that accompanies Emacs.
6516
6517** easy-mmode
6518
6519The easy-mmode package provides macros and functions that make
6520developing minor modes easier. Roughly, the programmer has to code
6521only the functionality of the minor mode. All the rest--toggles,
6522predicate, and documentation--can be done in one call to the macro
6523`easy-mmode-define-minor-mode' (see the documentation). See also
6524`easy-mmode-define-keymap'.
6525
6526** Text property changes
6527
6528*** The `intangible' property now works on overlays as well as on a
6529text property.
6530
6531*** The new functions next-char-property-change and
6532previous-char-property-change scan through the buffer looking for a
6533place where either a text property or an overlay might change. The
6534functions take two arguments, POSITION and LIMIT. POSITION is the
6535starting position for the scan. LIMIT says where to stop the scan.
6536
6537If no property change is found before LIMIT, the value is LIMIT. If
6538LIMIT is nil, scan goes to the beginning or end of the accessible part
6539of the buffer. If no property change is found, the value is the
6540position of the beginning or end of the buffer.
6541
6542*** In the `local-map' text property or overlay property, the property
6543value can now be a symbol whose function definition is a keymap. This
6544is an alternative to using the keymap itself.
6545
6546** Changes in invisibility features
6547
6548*** Isearch can now temporarily show parts of the buffer which are
6549hidden by an overlay with a invisible property, when the search match
6550is inside that portion of the buffer. To enable this the overlay
6551should have a isearch-open-invisible property which is a function that
6552would be called having the overlay as an argument, the function should
6553make the overlay visible.
6554
6555During incremental search the overlays are shown by modifying the
6556invisible and intangible properties, if beside this more actions are
6557needed the overlay should have a isearch-open-invisible-temporary
6558which is a function. The function is called with 2 arguments: one is
6559the overlay and the second is nil when it should show the overlay and
6560t when it should hide it.
6561
6562*** add-to-invisibility-spec, remove-from-invisibility-spec
6563
6564Modes that use overlays to hide portions of a buffer should set the
79214ddf
FP
6565invisible property of the overlay to the mode's name (or another symbol)
6566and modify the `buffer-invisibility-spec' to include that symbol.
a933dad1 6567Use `add-to-invisibility-spec' and `remove-from-invisibility-spec' to
79214ddf 6568manipulate the `buffer-invisibility-spec'.
a933dad1
DL
6569Here is an example of how to do this:
6570
6571 ;; If we want to display an ellipsis:
79214ddf 6572 (add-to-invisibility-spec '(my-symbol . t))
a933dad1 6573 ;; If you don't want ellipsis:
79214ddf 6574 (add-to-invisibility-spec 'my-symbol)
a933dad1
DL
6575
6576 ...
6577 (overlay-put (make-overlay beginning end) 'invisible 'my-symbol)
6578
6579 ...
6580 ;; When done with the overlays:
6581 (remove-from-invisibility-spec '(my-symbol . t))
6582 ;; Or respectively:
6583 (remove-from-invisibility-spec 'my-symbol)
6584
6585** Changes in syntax parsing.
6586
6587*** The syntax-directed buffer-scan functions (such as
6588`parse-partial-sexp', `forward-word' and similar functions) can now
6589obey syntax information specified by text properties, if the variable
6590`parse-sexp-lookup-properties' is non-nil.
6591
6592If the value of `parse-sexp-lookup-properties' is nil, the behavior
6593is as before: the syntax-table of the current buffer is always
6594used to determine the syntax of the character at the position.
6595
6596When `parse-sexp-lookup-properties' is non-nil, the syntax of a
6597character in the buffer is calculated thus:
6598
6599 a) if the `syntax-table' text-property of that character
6600 is a cons, this cons becomes the syntax-type;
6601
6602 Valid values of `syntax-table' text-property are: nil, a valid
6603 syntax-table, and a valid syntax-table element, i.e.,
6604 a cons cell of the form (SYNTAX-CODE . MATCHING-CHAR).
6605
6606 b) if the character's `syntax-table' text-property
6607 is a syntax table, this syntax table is used
6608 (instead of the syntax-table of the current buffer) to
6609 determine the syntax type of the character.
6610
6611 c) otherwise the syntax-type is determined by the syntax-table
6612 of the current buffer.
6613
6614*** The meaning of \s in regular expressions is also affected by the
6615value of `parse-sexp-lookup-properties'. The details are the same as
6616for the syntax-directed buffer-scan functions.
6617
6618*** There are two new syntax-codes, `!' and `|' (numeric values 14
6619and 15). A character with a code `!' starts a comment which is ended
6620only by another character with the same code (unless quoted). A
6621character with a code `|' starts a string which is ended only by
6622another character with the same code (unless quoted).
6623
6624These codes are mainly meant for use as values of the `syntax-table'
6625text property.
6626
6627*** The function `parse-partial-sexp' has new semantics for the sixth
6628arg COMMENTSTOP. If it is `syntax-table', parse stops after the start
6629of a comment or a string, or after end of a comment or a string.
6630
6631*** The state-list which the return value from `parse-partial-sexp'
6632(and can also be used as an argument) now has an optional ninth
6633element: the character address of the start of last comment or string;
6634nil if none. The fourth and eighth elements have special values if the
6635string/comment is started by a "!" or "|" syntax-code.
6636
6637*** Since new features of `parse-partial-sexp' allow a complete
6638syntactic parsing, `font-lock' no longer supports
6639`font-lock-comment-start-regexp'.
6640
6641** Changes in face features
6642
6643*** The face functions are now unconditionally defined in Emacs, even
6644if it does not support displaying on a device that supports faces.
6645
6646*** The function face-documentation returns the documentation string
6647of a face (or nil if it doesn't have one).
6648
6649*** The function face-bold-p returns t if a face should be bold.
6650set-face-bold-p sets that flag.
6651
6652*** The function face-italic-p returns t if a face should be italic.
6653set-face-italic-p sets that flag.
6654
6655*** You can now specify foreground and background colors for text
6656by adding elements of the form (foreground-color . COLOR-NAME)
6657and (background-color . COLOR-NAME) to the list of faces in
6658the `face' property (either the character's text property or an
6659overlay property).
6660
6661This means that you no longer need to create named faces to use
6662arbitrary colors in a Lisp package.
6663
6664** Changes in file-handling functions
6665
6666*** File-access primitive functions no longer discard an extra redundant
6667directory name from the beginning of the file name. In other words,
6668they no longer do anything special with // or /~. That conversion
6669is now done only in substitute-in-file-name.
6670
6671This makes it possible for a Lisp program to open a file whose name
6672begins with ~.
6673
6674*** If copy-file is unable to set the date of the output file,
6675it now signals an error with the condition file-date-error.
6676
6677*** The inode number returned by file-attributes may be an integer (if
6678the number fits in a Lisp integer) or a list of integers.
6679
6680*** insert-file-contents can now read from a special file,
6681as long as the arguments VISIT and REPLACE are nil.
6682
6683*** The RAWFILE arg to find-file-noselect, if non-nil, now suppresses
6684character code conversion as well as other things.
6685
6686Meanwhile, this feature does work with remote file names
6687(formerly it did not).
6688
6689*** Lisp packages which create temporary files should use the TMPDIR
6690environment variable to decide which directory to put them in.
6691
6692*** interpreter-mode-alist elements now specify regexps
6693instead of constant strings.
6694
6695*** expand-file-name no longer treats `//' or `/~' specially. It used
6696to delete all the text of a file name up through the first slash of
6697any `//' or `/~' sequence. Now it passes them straight through.
6698
6699substitute-in-file-name continues to treat those sequences specially,
6700in the same way as before.
6701
6702*** The variable `format-alist' is more general now.
6703The FROM-FN and TO-FN in a format definition can now be strings
6704which specify shell commands to use as filters to perform conversion.
6705
6706*** The new function access-file tries to open a file, and signals an
6707error if that fails. If the open succeeds, access-file does nothing
6708else, and returns nil.
6709
6710*** The function insert-directory now signals an error if the specified
6711directory cannot be listed.
6712
6713** Changes in minibuffer input
6714
6715*** The functions read-buffer, read-variable, read-command, read-string
6716read-file-name, read-from-minibuffer and completing-read now take an
6717additional argument which specifies the default value. If this
6718argument is non-nil, it should be a string; that string is used in two
6719ways:
6720
6721 It is returned if the user enters empty input.
6722 It is available through the history command M-n.
6723
6724*** The functions read-string, read-from-minibuffer,
6725read-no-blanks-input and completing-read now take an additional
6726argument INHERIT-INPUT-METHOD. If this is non-nil, then the
6727minibuffer inherits the current input method and the setting of
6728enable-multibyte-characters from the previously current buffer.
6729
6730In an interactive spec, you can use M instead of s to read an
6731argument in this way.
6732
6733*** All minibuffer input functions discard text properties
6734from the text you enter in the minibuffer, unless the variable
6735minibuffer-allow-text-properties is non-nil.
6736
6737** Echo area features
6738
6739*** Clearing the echo area now runs the normal hook
6740echo-area-clear-hook. Note that the echo area can be used while the
6741minibuffer is active; in that case, the minibuffer is still active
6742after the echo area is cleared.
6743
6744*** The function current-message returns the message currently displayed
6745in the echo area, or nil if there is none.
6746
6747** Keyboard input features
6748
6749*** tty-erase-char is a new variable that reports which character was
6750set up as the terminal's erase character when time Emacs was started.
6751
6752*** num-nonmacro-input-events is the total number of input events
6753received so far from the terminal. It does not count those generated
6754by keyboard macros.
6755
6756** Frame-related changes
6757
6758*** make-frame runs the normal hook before-make-frame-hook just before
6759creating a frame, and just after creating a frame it runs the abnormal
6760hook after-make-frame-functions with the new frame as arg.
6761
6762*** The new hook window-configuration-change-hook is now run every time
6763the window configuration has changed. The frame whose configuration
6764has changed is the selected frame when the hook is run.
6765
6766*** Each frame now independently records the order for recently
6767selected buffers, in its buffer-list frame parameter, so that the
6768value of other-buffer is now based on the buffers recently displayed
6769in the selected frame.
6770
6771*** The value of the frame parameter vertical-scroll-bars
6772is now `left', `right' or nil. A non-nil value specifies
6773which side of the window to put the scroll bars on.
6774
6775** X Windows features
6776
6777*** You can examine X resources for other applications by binding
6778x-resource-class around a call to x-get-resource. The usual value of
6779x-resource-class is "Emacs", which is the correct value for Emacs.
6780
6781*** In menus, checkboxes and radio buttons now actually work.
6782The menu displays the current status of the box or button.
6783
6784*** The function x-list-fonts now takes an optional fourth argument
6785MAXIMUM which sets a limit on how many matching fonts to return.
6786A smaller value of MAXIMUM makes the function faster.
6787
6788If the only question is whether *any* font matches the pattern,
6789it is good to supply 1 for this argument.
6790
6791** Subprocess features
6792
6793*** A reminder: it is no longer necessary for subprocess filter
6794functions and sentinels to do save-match-data, because Emacs does this
6795automatically.
6796
6797*** The new function shell-command-to-string executes a shell command
6798and returns the output from the command as a string.
6799
6800*** The new function process-contact returns t for a child process,
6801and (HOSTNAME SERVICE) for a net connection.
6802
6803** An error in running pre-command-hook or post-command-hook
6804does clear the variable to nil. The documentation was wrong before.
6805
6806** In define-key-after, if AFTER is t, the new binding now always goes
6807at the end of the keymap. If the keymap is a menu, this means it
6808goes after the other menu items.
6809
6810** If you have a program that makes several changes in the same area
79214ddf 6811of the buffer, you can use the macro combine-after-change-calls
a933dad1
DL
6812around that Lisp code to make it faster when after-change hooks
6813are in use.
6814
6815The macro arranges to call the after-change functions just once for a
6816series of several changes--if that seems safe.
6817
6818Don't alter the variables after-change-functions and
6819after-change-function within the body of a combine-after-change-calls
6820form.
6821
6822** If you define an abbrev (with define-abbrev) whose EXPANSION
6823is not a string, then the abbrev does not expand in the usual sense,
6824but its hook is still run.
6825
6826** Normally, the Lisp debugger is not used (even if you have enabled it)
6827for errors that are handled by condition-case.
6828
6829If you set debug-on-signal to a non-nil value, then the debugger is called
6830regardless of whether there is a handler for the condition. This is
6831useful for debugging problems that happen inside of a condition-case.
6832
6833This mode of operation seems to be unreliable in other ways. Errors that
6834are normal and ought to be handled, perhaps in timers or process
6835filters, will instead invoke the debugger. So don't say you weren't
6836warned.
6837
6838** The new variable ring-bell-function lets you specify your own
6839way for Emacs to "ring the bell".
6840
6841** If run-at-time's TIME argument is t, the action is repeated at
6842integral multiples of REPEAT from the epoch; this is useful for
6843functions like display-time.
6844
6845** You can use the function locate-library to find the precise file
6846name of a Lisp library. This isn't new, but wasn't documented before.
6847
6848** Commands for entering view mode have new optional arguments that
6849can be used from Lisp. Low-level entrance to and exit from view mode
6850is done by functions view-mode-enter and view-mode-exit.
6851
6852** batch-byte-compile-file now makes Emacs return a nonzero status code
6853if there is an error in compilation.
6854
6855** pop-to-buffer, switch-to-buffer-other-window and
6856switch-to-buffer-other-frame now accept an additional optional
6857argument NORECORD, much like switch-to-buffer. If it is non-nil,
6858they don't put the buffer at the front of the buffer list.
6859
6860** If your .emacs file leaves the *scratch* buffer non-empty,
6861Emacs does not display the startup message, so as to avoid changing
6862the *scratch* buffer.
6863
6864** The new function regexp-opt returns an efficient regexp to match a string.
6865The arguments are STRINGS and (optionally) PAREN. This function can be used
6866where regexp matching or searching is intensively used and speed is important,
6867e.g., in Font Lock mode.
6868
6869** The variable buffer-display-count is local to each buffer,
6870and is incremented each time the buffer is displayed in a window.
6871It starts at 0 when the buffer is created.
6872
6873** The new function compose-mail starts composing a mail message
6874using the user's chosen mail composition agent (specified with the
6875variable mail-user-agent). It has variants compose-mail-other-window
6876and compose-mail-other-frame.
6877
6878** The `user-full-name' function now takes an optional parameter which
6879can either be a number (the UID) or a string (the login name). The
6880full name of the specified user will be returned.
6881
6882** Lisp packages that load files of customizations, or any other sort
6883of user profile, should obey the variable init-file-user in deciding
6884where to find it. They should load the profile of the user name found
6885in that variable. If init-file-user is nil, meaning that the -q
6886option was used, then Lisp packages should not load the customization
6887files at all.
6888
6889** format-time-string now allows you to specify the field width
6890and type of padding. This works as in printf: you write the field
6891width as digits in the middle of a %-construct. If you start
6892the field width with 0, it means to pad with zeros.
6893
6894For example, %S normally specifies the number of seconds since the
6895minute; %03S means to pad this with zeros to 3 positions, %_3S to pad
6896with spaces to 3 positions. Plain %3S pads with zeros, because that
6897is how %S normally pads to two positions.
6898
6899** thing-at-point now supports a new kind of "thing": url.
6900
6901** imenu.el changes.
6902
6903You can now specify a function to be run when selecting an
79214ddf 6904item from menu created by imenu.
a933dad1
DL
6905
6906An example of using this feature: if we define imenu items for the
6907#include directives in a C file, we can open the included file when we
6908select one of those items.
6909\f
6910* Emacs 19.34 is a bug-fix release with no user-visible changes.
6911\f
6912* Changes in Emacs 19.33.
6913
6914** Bibtex mode no longer turns on Auto Fill automatically. (No major
6915mode should do that--it is the user's choice.)
6916
6917** The variable normal-auto-fill-function specifies the function to
6918use for auto-fill-function, if and when Auto Fill is turned on.
6919Major modes can set this locally to alter how Auto Fill works.
6920\f
6921* Editing Changes in Emacs 19.32
6922
6923** C-x f with no argument now signals an error.
6924To set the fill column at the current column, use C-u C-x f.
6925
6926** Expanding dynamic abbrevs with M-/ is now smarter about case
6927conversion. If you type the abbreviation with mixed case, and it
6928matches the beginning of the expansion including case, then the
6929expansion is copied verbatim. Using SPC M-/ to copy an additional
6930word always copies it verbatim except when the previous copied word is
6931all caps.
6932
6933** On a non-windowing terminal, which can display only one Emacs frame
6934at a time, creating a new frame with C-x 5 2 also selects that frame.
6935
6936When using a display that can show multiple frames at once, C-x 5 2
6937does make the frame visible, but does not select it. This is the same
6938as in previous Emacs versions.
6939
6940** You can use C-x 5 2 to create multiple frames on MSDOS, just as on a
6941non-X terminal on Unix. Of course, only one frame is visible at any
6942time, since your terminal doesn't have the ability to display multiple
6943frames.
6944
6945** On Windows, set win32-pass-alt-to-system to a non-nil value
6946if you would like tapping the Alt key to invoke the Windows menu.
6947This feature is not enabled by default; since the Alt key is also the
6948Meta key, it is too easy and painful to activate this feature by
6949accident.
6950
6951** The command apply-macro-to-region-lines repeats the last defined
6952keyboard macro once for each complete line within the current region.
6953It does this line by line, by moving point to the beginning of that
6954line and then executing the macro.
6955
6956This command is not new, but was never documented before.
6957
6958** You can now use Mouse-1 to place the region around a string constant
6959(something surrounded by doublequote characters or other delimiter
6960characters of like syntax) by double-clicking on one of the delimiting
6961characters.
6962
6963** Font Lock mode
6964
6965*** Font Lock support modes
6966
6967Font Lock can be configured to use Fast Lock mode and Lazy Lock mode (see
6968below) in a flexible way. Rather than adding the appropriate function to the
6969hook font-lock-mode-hook, you can use the new variable font-lock-support-mode
6970to control which modes have Fast Lock mode or Lazy Lock mode turned on when
6971Font Lock mode is enabled.
6972
6973For example, to use Fast Lock mode when Font Lock mode is turned on, put:
6974
6975 (setq font-lock-support-mode 'fast-lock-mode)
6976
6977in your ~/.emacs.
6978
6979*** lazy-lock
6980
6981The lazy-lock package speeds up Font Lock mode by making fontification occur
6982only when necessary, such as when a previously unfontified part of the buffer
6983becomes visible in a window. When you create a buffer with Font Lock mode and
6984Lazy Lock mode turned on, the buffer is not fontified. When certain events
6985occur (such as scrolling), Lazy Lock makes sure that the visible parts of the
6986buffer are fontified. Lazy Lock also defers on-the-fly fontification until
6987Emacs has been idle for a given amount of time.
6988
6989To use this package, put in your ~/.emacs:
6990
6991 (setq font-lock-support-mode 'lazy-lock-mode)
6992
6993To control the package behaviour, see the documentation for `lazy-lock-mode'.
6994
6995** Changes in BibTeX mode.
6996
6997*** For all entries allow spaces and tabs between opening brace or
6998paren and key.
6999
7000*** Non-escaped double-quoted characters (as in `Sch"of') are now
7001supported.
7002
7003** Gnus changes.
7004
7005Gnus, the Emacs news reader, has undergone further rewriting. Many new
7006commands and variables have been added. There should be no
7007significant incompatibilities between this Gnus version and the
7008previously released version, except in the message composition area.
7009
7010Below is a list of the more user-visible changes. Coding changes
7011between Gnus 5.1 and 5.2 are more extensive.
7012
79214ddf 7013*** A new message composition mode is used. All old customization
a933dad1
DL
7014variables for mail-mode, rnews-reply-mode and gnus-msg are now
7015obsolete.
7016
7017*** Gnus is now able to generate "sparse" threads -- threads where
7018missing articles are represented by empty nodes.
7019
7020 (setq gnus-build-sparse-threads 'some)
7021
7022*** Outgoing articles are stored on a special archive server.
7023
7024 To disable this: (setq gnus-message-archive-group nil)
7025
7026*** Partial thread regeneration now happens when articles are
79214ddf 7027referred.
a933dad1
DL
7028
7029*** Gnus can make use of GroupLens predictions:
7030
7031 (setq gnus-use-grouplens t)
7032
7033*** A trn-line tree buffer can be displayed.
7034
7035 (setq gnus-use-trees t)
7036
7037*** An nn-like pick-and-read minor mode is available for the summary
79214ddf 7038buffers.
a933dad1
DL
7039
7040 (add-hook 'gnus-summary-mode-hook 'gnus-pick-mode)
7041
7042*** In binary groups you can use a special binary minor mode:
7043
7044 `M-x gnus-binary-mode'
7045
7046*** Groups can be grouped in a folding topic hierarchy.
7047
7048 (add-hook 'gnus-group-mode-hook 'gnus-topic-mode)
7049
7050*** Gnus can re-send and bounce mail.
7051
7052 Use the `S D r' and `S D b'.
7053
7054*** Groups can now have a score, and bubbling based on entry frequency
7055is possible.
7056
7057 (add-hook 'gnus-summary-exit-hook 'gnus-summary-bubble-group)
7058
7059*** Groups can be process-marked, and commands can be performed on
7060groups of groups.
7061
7062*** Caching is possible in virtual groups.
7063
7064*** nndoc now understands all kinds of digests, mail boxes, rnews news
79214ddf 7065batches, ClariNet briefs collections, and just about everything else.
a933dad1
DL
7066
7067*** Gnus has a new backend (nnsoup) to create/read SOUP packets.
7068
7069*** The Gnus cache is much faster.
7070
7071*** Groups can be sorted according to many criteria.
7072
7073 For instance: (setq gnus-group-sort-function 'gnus-group-sort-by-rank)
7074
7075*** New group parameters have been introduced to set list-address and
7076expiration times.
7077
7078*** All formatting specs allow specifying faces to be used.
7079
7080*** There are several more commands for setting/removing/acting on
7081process marked articles on the `M P' submap.
7082
7083*** The summary buffer can be limited to show parts of the available
7084articles based on a wide range of criteria. These commands have been
7085bound to keys on the `/' submap.
7086
7087*** Articles can be made persistent -- as an alternative to saving
7088articles with the `*' command.
7089
7090*** All functions for hiding article elements are now toggles.
7091
7092*** Article headers can be buttonized.
7093
7094 (add-hook 'gnus-article-display-hook 'gnus-article-add-buttons-to-head)
7095
7096*** All mail backends support fetching articles by Message-ID.
7097
79214ddf 7098*** Duplicate mail can now be treated properly. See the
a933dad1
DL
7099`nnmail-treat-duplicates' variable.
7100
7101*** All summary mode commands are available directly from the article
79214ddf 7102buffer.
a933dad1
DL
7103
7104*** Frames can be part of `gnus-buffer-configuration'.
7105
7106*** Mail can be re-scanned by a daemonic process.
7107
7108*** Gnus can make use of NoCeM files to filter spam.
7109
7110 (setq gnus-use-nocem t)
7111
79214ddf 7112*** Groups can be made permanently visible.
a933dad1
DL
7113
7114 (setq gnus-permanently-visible-groups "^nnml:")
7115
79214ddf 7116*** Many new hooks have been introduced to make customizing easier.
a933dad1
DL
7117
7118*** Gnus respects the Mail-Copies-To header.
7119
79214ddf 7120*** Threads can be gathered by looking at the References header.
a933dad1 7121
79214ddf 7122 (setq gnus-summary-thread-gathering-function
a933dad1
DL
7123 'gnus-gather-threads-by-references)
7124
7125*** Read articles can be stored in a special backlog buffer to avoid
79214ddf 7126refetching.
a933dad1
DL
7127
7128 (setq gnus-keep-backlog 50)
7129
7130*** A clean copy of the current article is always stored in a separate
7131buffer to allow easier treatment.
7132
7133*** Gnus can suggest where to save articles. See `gnus-split-methods'.
7134
7135*** Gnus doesn't have to do as much prompting when saving.
7136
7137 (setq gnus-prompt-before-saving t)
7138
7139*** gnus-uu can view decoded files asynchronously while fetching
79214ddf 7140articles.
a933dad1
DL
7141
7142 (setq gnus-uu-grabbed-file-functions 'gnus-uu-grab-view)
7143
79214ddf 7144*** Filling in the article buffer now works properly on cited text.
a933dad1
DL
7145
7146*** Hiding cited text adds buttons to toggle hiding, and how much
7147cited text to hide is now customizable.
7148
7149 (setq gnus-cited-lines-visible 2)
7150
7151*** Boring headers can be hidden.
7152
7153 (add-hook 'gnus-article-display-hook 'gnus-article-hide-boring-headers)
7154
7155*** Default scoring values can now be set from the menu bar.
7156
7157*** Further syntax checking of outgoing articles have been added.
7158
7159The Gnus manual has been expanded. It explains all these new features
7160in greater detail.
7161\f
7162* Lisp Changes in Emacs 19.32
7163
7164** The function set-visited-file-name now accepts an optional
7165second argument NO-QUERY. If it is non-nil, then the user is not
7166asked for confirmation in the case where the specified file already
7167exists.
7168
7169** The variable print-length applies to printing vectors and bitvectors,
7170as well as lists.
7171
7172** The new function keymap-parent returns the parent keymap
7173of a given keymap.
7174
7175** The new function set-keymap-parent specifies a new parent for a
7176given keymap. The arguments are KEYMAP and PARENT. PARENT must be a
7177keymap or nil.
7178
7179** Sometimes menu keymaps use a command name, a symbol, which is really
7180an automatically generated alias for some other command, the "real"
7181name. In such a case, you should give that alias symbol a non-nil
7182menu-alias property. That property tells the menu system to look for
7183equivalent keys for the real name instead of equivalent keys for the
7184alias.
7185\f
7186* Editing Changes in Emacs 19.31
7187
7188** Freedom of the press restricted in the United States.
7189
7190Emacs has been censored in accord with the Communications Decency Act.
7191This includes removing some features of the doctor program. That law
7192was described by its supporters as a ban on pornography, but it bans
7193far more than that. The Emacs distribution has never contained any
7194pornography, but parts of it were nonetheless prohibited.
7195
7196For information on US government censorship of the Internet, and what
7197you can do to bring back freedom of the press, see the web site
7198`http://www.vtw.org/'.
7199
7200** A note about C mode indentation customization.
7201
7202The old (Emacs 19.29) ways of specifying a C indentation style
7203do not normally work in the new implementation of C mode.
7204It has its own methods of customizing indentation, which are
7205much more powerful than the old C mode. See the Editing Programs
7206chapter of the manual for details.
7207
7208However, you can load the library cc-compat to make the old
7209customization variables take effect.
7210
7211** Marking with the mouse.
7212
7213When you mark a region with the mouse, the region now remains
7214highlighted until the next input event, regardless of whether you are
7215using M-x transient-mark-mode.
7216
7217** Improved Windows NT/95 support.
7218
7219*** Emacs now supports scroll bars on Windows NT and Windows 95.
7220
7221*** Emacs now supports subprocesses on Windows 95. (Subprocesses used
7222to work on NT only and not on 95.)
7223
7224*** There are difficulties with subprocesses, though, due to problems
7225in Windows, beyond the control of Emacs. They work fine as long as
7226you run Windows applications. The problems arise when you run a DOS
7227application in a subprocesses. Since current shells run as DOS
7228applications, these problems are significant.
7229
7230If you run a DOS application in a subprocess, then the application is
7231likely to busy-wait, which means that your machine will be 100% busy.
7232However, if you don't mind the temporary heavy load, the subprocess
7233will work OK as long as you tell it to terminate before you start any
7234other DOS application as a subprocess.
7235
7236Emacs is unable to terminate or interrupt a DOS subprocess.
7237You have to do this by providing input directly to the subprocess.
7238
7239If you run two DOS applications at the same time in two separate
7240subprocesses, even if one of them is asynchronous, you will probably
7241have to reboot your machine--until then, it will remain 100% busy.
7242Windows simply does not cope when one Windows process tries to run two
7243separate DOS subprocesses. Typing CTL-ALT-DEL and then choosing
7244Shutdown seems to work although it may take a few minutes.
7245
7246** M-x resize-minibuffer-mode.
7247
7248This command, not previously mentioned in NEWS, toggles a mode in
7249which the minibuffer window expands to show as many lines as the
7250minibuffer contains.
7251
7252** `title' frame parameter and resource.
7253
7254The `title' X resource now specifies just the frame title, nothing else.
7255It does not affect the name used for looking up other X resources.
7256It works by setting the new `title' frame parameter, which likewise
7257affects just the displayed title of the frame.
7258
7259The `name' parameter continues to do what it used to do:
7260it specifies the frame name for looking up X resources,
7261and also serves as the default for the displayed title
7262when the `title' parameter is unspecified or nil.
7263
7264** Emacs now uses the X toolkit by default, if you have a new
7265enough version of X installed (X11R5 or newer).
7266
7267** When you compile Emacs with the Motif widget set, Motif handles the
7268F10 key by activating the menu bar. To avoid confusion, the usual
7269Emacs binding of F10 is replaced with a no-op when using Motif.
7270
7271If you want to be able to use F10 in Emacs, you can rebind the Motif
7272menubar to some other key which you don't use. To do so, add
7273something like this to your X resources file. This example rebinds
7274the Motif menu bar activation key to S-F12:
7275
7276 Emacs*defaultVirtualBindings: osfMenuBar : Shift<Key>F12
7277
7278** In overwrite mode, DEL now inserts spaces in most cases
7279to replace the characters it "deletes".
7280
7281** The Rmail summary now shows the number of lines in each message.
7282
7283** Rmail has a new command M-x unforward-rmail-message, which extracts
7284a forwarded message from the message that forwarded it. To use it,
7285select a message which contains a forwarded message and then type the command.
7286It inserts the forwarded message as a separate Rmail message
7287immediately after the selected one.
7288
7289This command also undoes the textual modifications that are standardly
7290made, as part of forwarding, by Rmail and other mail reader programs.
7291
7292** Turning off saving of .saves-... files in your home directory.
7293
7294Each Emacs session writes a file named .saves-... in your home
7295directory to record which files M-x recover-session should recover.
7296If you exit Emacs normally with C-x C-c, it deletes that file. If
7297Emacs or the operating system crashes, the file remains for M-x
7298recover-session.
7299
7300You can turn off the writing of these files by setting
7301auto-save-list-file-name to nil. If you do this, M-x recover-session
7302will not work.
7303
7304Some previous Emacs versions failed to delete these files even on
7305normal exit. This is fixed now. If you are thinking of turning off
7306this feature because of past experiences with versions that had this
7307bug, it would make sense to check whether you still want to do so
7308now that the bug is fixed.
7309
7310** Changes to Version Control (VC)
7311
7312There is a new variable, vc-follow-symlinks. It indicates what to do
7313when you visit a link to a file that is under version control.
7314Editing the file through the link bypasses the version control system,
7315which is dangerous and probably not what you want.
7316
7317If this variable is t, VC follows the link and visits the real file,
7318telling you about it in the echo area. If it is `ask' (the default),
7319VC asks for confirmation whether it should follow the link. If nil,
7320the link is visited and a warning displayed.
7321
7322** iso-acc.el now lets you specify a choice of language.
7323Languages include "latin-1" (the default) and "latin-2" (which
7324is designed for entering ISO Latin-2 characters).
7325
7326There are also choices for specific human languages such as French and
7327Portuguese. These are subsets of Latin-1, which differ in that they
7328enable only the accent characters needed for particular language.
7329The other accent characters, not needed for the chosen language,
7330remain normal.
7331
7332** Posting articles and sending mail now has M-TAB completion on various
7333header fields (Newsgroups, To, CC, ...).
7334
7335Completion in the Newsgroups header depends on the list of groups
7336known to your news reader. Completion in the Followup-To header
7337offers those groups which are in the Newsgroups header, since
7338Followup-To usually just holds one of those.
7339
7340Completion in fields that hold mail addresses works based on the list
7341of local users plus your aliases. Additionally, if your site provides
7342a mail directory or a specific host to use for any unrecognized user
7343name, you can arrange to query that host for completion also. (See the
7344documentation of variables `mail-directory-process' and
7345`mail-directory-stream'.)
7346
7347** A greatly extended sgml-mode offers new features such as (to be configured)
7348skeletons with completing read for tags and attributes, typing named
7349characters including optionally all 8bit characters, making tags invisible
7350with optional alternate display text, skipping and deleting tag(pair)s.
7351
7352Note: since Emacs' syntax feature cannot limit the special meaning of ', " and
7353- to inside <>, for some texts the result, especially of font locking, may be
7354wrong (see `sgml-specials' if you get wrong results).
7355
7356The derived html-mode configures this with tags and attributes more or
7357less HTML3ish. It also offers optional quick keys like C-c 1 for
7358headline or C-c u for unordered list (see `html-quick-keys'). Edit /
7359Text Properties / Face or M-g combinations create tags as applicable.
7360Outline minor mode is supported and level 1 font-locking tries to
7361fontify tag contents (which only works when they fit on one line, due
7362to a limitation in font-lock).
7363
7364External viewing via browse-url can occur automatically upon saving.
7365
7366** M-x imenu-add-to-menubar now adds to the menu bar for the current
7367buffer only. If you want to put an Imenu item in the menu bar for all
7368buffers that use a particular major mode, use the mode hook, as in
7369this example:
7370
7371 (add-hook 'emacs-lisp-mode-hook
7372 '(lambda () (imenu-add-to-menubar "Index")))
7373
7374** Changes in BibTeX mode.
7375
7376*** Field names may now contain digits, hyphens, and underscores.
7377
7378*** Font Lock mode is now supported.
7379
7380*** bibtex-make-optional-field is no longer interactive.
7381
7382*** If bibtex-maintain-sorted-entries is non-nil, inserting new
7383entries is now done with a faster algorithm. However, inserting
7384will fail in this case if the buffer contains invalid entries or
7385isn't in sorted order, so you should finish each entry with C-c C-c
7386(bibtex-close-entry) after you have inserted or modified it.
7387The default value of bibtex-maintain-sorted-entries is nil.
7388
7389*** Function `show-all' is no longer bound to a key, since C-u C-c C-q
7390does the same job.
7391
7392*** Entries with quotes inside quote-delimited fields (as `author =
7393"Stefan Sch{\"o}f"') are now supported.
7394
7395*** Case in field names doesn't matter anymore when searching for help
7396text.
7397
7398** Font Lock mode
7399
7400*** Global Font Lock mode
7401
7402Font Lock mode can be turned on globally, in buffers that support it, by the
7403new command global-font-lock-mode. You can use the new variable
7404font-lock-global-modes to control which modes have Font Lock mode automagically
7405turned on. By default, this variable is set so that Font Lock mode is turned
7406on globally where the buffer mode supports it.
7407
7408For example, to automagically turn on Font Lock mode where supported, put:
7409
7410 (global-font-lock-mode t)
7411
7412in your ~/.emacs.
7413
7414*** Local Refontification
7415
7416In Font Lock mode, editing a line automatically refontifies that line only.
7417However, if your change alters the syntactic context for following lines,
7418those lines remain incorrectly fontified. To refontify them, use the new
7419command M-g M-g (font-lock-fontify-block).
7420
7421In certain major modes, M-g M-g refontifies the entire current function.
7422(The variable font-lock-mark-block-function controls how to find the
7423current function.) In other major modes, M-g M-g refontifies 16 lines
7424above and below point.
7425
7426With a prefix argument N, M-g M-g refontifies N lines above and below point.
7427
7428** Follow mode
7429
7430Follow mode is a new minor mode combining windows showing the same
7431buffer into one tall "virtual window". The windows are typically two
7432side-by-side windows. Follow mode makes them scroll together as if
7433they were a unit. To use it, go to a frame with just one window,
7434split it into two side-by-side windows using C-x 3, and then type M-x
7435follow-mode.
7436
7437M-x follow-mode turns off Follow mode if it is already enabled.
7438
7439To display two side-by-side windows and activate Follow mode, use the
7440command M-x follow-delete-other-windows-and-split.
7441
7442** hide-show changes.
7443
7444The hooks hs-hide-hooks and hs-show-hooks have been renamed
7445to hs-hide-hook and hs-show-hook, to follow the convention for
7446normal hooks.
7447
7448** Simula mode now has a menu containing the most important commands.
7449The new command simula-indent-exp is bound to C-M-q.
7450
7451** etags can now handle programs written in Erlang. Files are
7452recognised by the extensions .erl and .hrl. The tagged lines are
7453those that begin a function, record, or macro.
7454
7455** MSDOS Changes
7456
7457*** It is now possible to compile Emacs with the version 2 of DJGPP.
7458Compilation with DJGPP version 1 also still works.
7459
7460*** The documentation of DOS-specific aspects of Emacs was rewritten
7461and expanded; see the ``MS-DOS'' node in the on-line docs.
7462
7463*** Emacs now uses ~ for backup file names, not .bak.
7464
7465*** You can simulate mouse-3 on two-button mice by simultaneously
7466pressing both mouse buttons.
7467
7468*** A number of packages and commands which previously failed or had
7469restricted functionality on MS-DOS, now work. The most important ones
79214ddf 7470are:
a933dad1
DL
7471
7472**** Printing (both with `M-x lpr-buffer' and with `ps-print' package)
7473now works.
7474
7475**** `Ediff' works (in a single-frame mode).
7476
7477**** `M-x display-time' can be used on MS-DOS (due to the new
7478implementation of Emacs timers, see below).
7479
7480**** `Dired' supports Unix-style shell wildcards.
7481
7482**** The `c-macro-expand' command now works as on other platforms.
7483
7484**** `M-x recover-session' works.
7485
7486**** `M-x list-colors-display' displays all the available colors.
7487
7488**** The `TPU-EDT' package works.
7489\f
7490* Lisp changes in Emacs 19.31.
7491
7492** The function using-unix-filesystems on Windows NT and Windows 95
7493tells Emacs to read and write files assuming that they reside on a
7494remote Unix filesystem. No CR/LF translation is done on any files in
7495this case. Invoking using-unix-filesystems with t activates this
7496behavior, and invoking it with any other value deactivates it.
7497
7498** Change in system-type and system-configuration values.
7499
7500The value of system-type on a Linux-based GNU system is now `lignux',
7501not `linux'. This means that some programs which use `system-type'
7502need to be changed. The value of `system-configuration' will also
7503be different.
7504
7505It is generally recommended to use `system-configuration' rather
7506than `system-type'.
7507
7508See the file LINUX-GNU in this directory for more about this.
7509
7510** The functions shell-command and dired-call-process
7511now run file name handlers for default-directory, if it has them.
7512
7513** Undoing the deletion of text now restores the positions of markers
7514that pointed into or next to the deleted text.
7515
7516** Timers created with run-at-time now work internally to Emacs, and
7517no longer use a separate process. Therefore, they now work more
7518reliably and can be used for shorter time delays.
7519
7520The new function run-with-timer is a convenient way to set up a timer
7521to run a specified amount of time after the present. A call looks
7522like this:
7523
7524 (run-with-timer SECS REPEAT FUNCTION ARGS...)
7525
7526SECS says how many seconds should elapse before the timer happens.
7527It may be an integer or a floating point number. When the timer
7528becomes ripe, the action is to call FUNCTION with arguments ARGS.
7529
7530REPEAT gives the interval for repeating the timer (measured in
7531seconds). It may be an integer or a floating point number. nil or 0
7532means don't repeat at all--call FUNCTION just once.
7533
7534*** with-timeout provides an easy way to do something but give
7535up if too much time passes.
7536
7537 (with-timeout (SECONDS TIMEOUT-FORMS...) BODY...)
7538
7539This executes BODY, but gives up after SECONDS seconds.
7540If it gives up, it runs the TIMEOUT-FORMS and returns the value
7541of the last one of them. Normally it returns the value of the last
7542form in BODY.
7543
7544*** You can now arrange to call a function whenever Emacs is idle for
7545a certain length of time. To do this, call run-with-idle-timer. A
7546call looks like this:
7547
7548 (run-with-idle-timer SECS REPEAT FUNCTION ARGS...)
7549
7550SECS says how many seconds of idleness should elapse before the timer
7551runs. It may be an integer or a floating point number. When the
7552timer becomes ripe, the action is to call FUNCTION with arguments
7553ARGS.
7554
7555Emacs becomes idle whenever it finishes executing a keyboard or mouse
7556command. It remains idle until it receives another keyboard or mouse
7557command.
7558
7559REPEAT, if non-nil, means this timer should be activated again each
7560time Emacs becomes idle and remains idle for SECS seconds The timer
7561does not repeat if Emacs *remains* idle; it runs at most once after
7562each time Emacs becomes idle.
7563
7564If REPEAT is nil, the timer runs just once, the first time Emacs is
7565idle for SECS seconds.
7566
7567*** post-command-idle-hook is now obsolete; you shouldn't use it at
7568all, because it interferes with the idle timer mechanism. If your
7569programs use post-command-idle-hook, convert them to use idle timers
7570instead.
7571
7572*** y-or-n-p-with-timeout lets you ask a question but give up if
7573there is no answer within a certain time.
7574
7575 (y-or-n-p-with-timeout PROMPT SECONDS DEFAULT-VALUE)
7576
7577asks the question PROMPT (just like y-or-n-p). If the user answers
7578within SECONDS seconds, it returns the answer that the user gave.
7579Otherwise it gives up after SECONDS seconds, and returns DEFAULT-VALUE.
7580
7581** Minor change to `encode-time': you can now pass more than seven
7582arguments. If you do that, the first six arguments have the usual
7583meaning, the last argument is interpreted as the time zone, and the
7584arguments in between are ignored.
7585
7586This means that it works to use the list returned by `decode-time' as
7587the list of arguments for `encode-time'.
7588
7589** The default value of load-path now includes the directory
7590/usr/local/share/emacs/VERSION/site-lisp In addition to
7591/usr/local/share/emacs/site-lisp. You can use this new directory for
7592site-specific Lisp packages that belong with a particular Emacs
7593version.
7594
7595It is not unusual for a Lisp package that works well in one Emacs
7596version to cause trouble in another. Sometimes packages need updating
7597for incompatible changes; sometimes they look at internal data that
7598has changed; sometimes the package has been installed in Emacs itself
7599and the installed version should be used. Whatever the reason for the
7600problem, this new feature makes it easier to solve.
7601
7602** When your program contains a fixed file name (like .completions or
7603.abbrev.defs), the file name usually needs to be different on operating
7604systems with limited file name syntax.
7605
7606Now you can avoid ad-hoc conditionals by using the function
7607convert-standard-filename to convert the file name to a proper form
7608for each operating system. Here is an example of use, from the file
7609completions.el:
7610
7611(defvar save-completions-file-name
7612 (convert-standard-filename "~/.completions")
7613 "*The filename to save completions to.")
7614
7615This sets the variable save-completions-file-name to a value that
7616depends on the operating system, because the definition of
7617convert-standard-filename depends on the operating system. On
7618Unix-like systems, it returns the specified file name unchanged. On
7619MS-DOS, it adapts the name to fit the limitations of that system.
7620
7621** The interactive spec N now returns the numeric prefix argument
7622rather than the raw prefix argument. (It still reads a number using the
7623minibuffer if there is no prefix argument at all.)
7624
7625** When a process is deleted, this no longer disconnects the process
7626marker from its buffer position.
7627
7628** The variable garbage-collection-messages now controls whether
7629Emacs displays a message at the beginning and end of garbage collection.
7630The default is nil, meaning there are no messages.
7631
7632** The variable debug-ignored-errors specifies certain kinds of errors
7633that should not enter the debugger. Its value is a list of error
7634condition symbols and/or regular expressions. If the error has any
7635of the condition symbols listed, or if any of the regular expressions
7636matches the error message, then that error does not enter the debugger,
7637regardless of the value of debug-on-error.
7638
7639This variable is initialized to match certain common but uninteresting
7640errors that happen often during editing.
7641
7642** The new function error-message-string converts an error datum
7643into its error message. The error datum is what condition-case
7644puts into the variable, to describe the error that happened.
7645
7646** Anything that changes which buffer appears in a given window
7647now runs the window-scroll-functions for that window.
7648
7649** The new function get-buffer-window-list returns a list of windows displaying
7650a buffer. The function is called with the buffer (a buffer object or a buffer
7651name) and two optional arguments specifying the minibuffer windows and frames
7652to search. Therefore this function takes optional args like next-window etc.,
7653and not get-buffer-window.
7654
7655** buffer-substring now runs the hook buffer-access-fontify-functions,
7656calling each function with two arguments--the range of the buffer
7657being accessed. buffer-substring-no-properties does not call them.
7658
7659If you use this feature, you should set the variable
7660buffer-access-fontified-property to a non-nil symbol, which is a
7661property name. Then, if all the characters in the buffer range have a
7662non-nil value for that property, the buffer-access-fontify-functions
7663are not called. When called, these functions should put a non-nil
7664property on the text that they fontify, so that they won't get called
7665over and over for the same text.
7666
7667** Changes in lisp-mnt.el
7668
7669*** The lisp-mnt package can now recognize file headers that are written
7670in the formats used by the `what' command and the RCS `ident' command:
7671
7672;; @(#) HEADER: text
7673;; $HEADER: text $
7674
7675in addition to the normal
7676
7677;; HEADER: text
7678
7679*** The commands lm-verify and lm-synopsis are now interactive. lm-verify
7680checks that the library file has proper sections and headers, and
7681lm-synopsis extracts first line "synopsis'"information.
7682\f
7683* For older news, see the file ONEWS.
7684
7685----------------------------------------------------------------------
7686Copyright information:
7687
404fa7d6 7688Copyright (C) 1996, 1997, 1998, 1999, 2000 Free Software Foundation, Inc.
a933dad1
DL
7689
7690 Permission is granted to anyone to make or distribute verbatim copies
7691 of this document as received, in any medium, provided that the
7692 copyright notice and this permission notice are preserved,
7693 thus giving the recipient permission to redistribute in turn.
7694
7695 Permission is granted to distribute modified versions
7696 of this document, or of portions of it,
7697 under the above conditions, provided also that they
7698 carry prominent notices stating who last changed them.
7699\f
7700Local variables:
7701mode: outline
7702paragraph-separate: "[ \f]*$"
7703end: