6 This file presents the changes in recent XEmacs versions. It
7 primarily documents user-visible (interface) changes, but also
8 includes internal changes of possible interest to the users. When
9 describing new features, we try to also document ways of reverting to
10 the old behavior, where applicable. If you dislike a recent change in
11 how XEmacs behaves, this file might contain a remedy.
13 Use `C-c C-f' to move to the next equal level of outline, and
14 `C-c C-b' to move to previous equal level. `C-h m' will give more
15 info about the Outline mode. Many commands are also available through
18 Users who would like to know which capabilities have been introduced
19 in each release should look at the appropriate section of this file.
20 Starting with version 20.0, XEmacs includes ChangeLogs, which can be
21 consulted for a more detailed list of changes.
23 N.B. The term "GNU Emacs" refers to any release of Emacs Version
24 19 from the Free Software Foundation's GNU Project. (We do not
25 say just "Emacs" as Richard M. Stallman ["RMS"] prefers, because
26 it is clearly a more generic term.) The term "XEmacs" refers to
27 this program or sometimes to its predecessors "Era" and "Lucid
28 Emacs". The predecessor of all these program is called "Emacs
29 18". When no particular version is implied, "Emacs" will be used.
32 * Changes in XEmacs 21.4
33 ========================
35 ** The delete key now deletes forward by default.
37 This is regulated by the variable `delete-key-deletes-forward', which
38 now defaults to t. `delete-key-deletes-forward' takes effect only on
39 the systems that offer both a backspace and a delete key. If set to
40 nil, the key labeled "Delete" will always delete backward. If set to
41 non-nil, the "Delete" key will delete forward, except on keyboards
42 where a "Backspace" key is not provided (e.g. old DEC keyboards.)
44 Unless our implementation has bugs, the only reason why you would want
45 to set `delete-key-deletes-forward' to nil is if you want to use the
46 Delete key to delete backwards, despite the presence (according to
47 Xlib) of a BackSpace key on the keyboard.
49 ** You can now build XEmacs with support for GTK+ widget set.
51 XEmacs built that way uses GTK+ to draw menubars, scrollbars, and
52 other GUI components, as well GDK for drawing text, choosing fonts,
53 allocating colors, etc. Additionally, GTK-XEmacs supports Lisp
54 functions for writing your own GTK programs in Emacs Lisp!
56 To use this, build XEmacs with the `--with-gtk' configure flag. (Of
57 course, you'll need to have the GTK+ libraries and header files on the
58 system.) Gnome widgets and functionality are supported where
59 available, and can be turned off.
61 ** Shifted motion keys now select text by default. You can turn this
62 off by setting `shifted-motion-keys-select-region' to nil.
64 ** There is a new command `kill-entire-line' that always kills the
65 entire line at point, regardless of whether the point is at the
66 beginning of line, and regardless of the setting of `kill-whole-line'.
68 ** The variable `kill-whole-line' now only takes effect when kill-line
69 is called interactively. Although this is a departure from a previous
70 behavior in the case of setting this variable kill-whole-line to t,
71 it is almost certainly what has always been intended, and most likely
72 the old way of doing things introduced bugs.
74 ** The help buffers created by the plethora of C-h commands now
77 ** The modeline's text is now scrollable. This is controlled by the
78 variable `modeline-scrolling-method', which you need to set to a
79 non-nil value. You can also choose scrolling types; see the docstring
80 of `modeline-scrolling-method' for more information.
82 ** XEmacs menus now have accelerators by default. If a menu item does
83 not have an accelerator specified, one is created dynamically, using
84 numbers 1-9 and letters.
86 ** Interactive searching and matching case improvements.
88 Case sensitiveness in searching operations is normally controlled by
89 the variable `case-fold-search' (if non-nil, case is ignored while
90 searching). This mechanism has now been slightly improved for
91 interactive searches: if the search string (or regexp) contains
92 uppercase characters, the searching is forced to be case-sensitive,
95 The new behavior affects all functions performing interactive
96 searches, like `zap-to-char', `list-matching-lines', `tags-search'
97 etc. The incremental search facility has always behaved that way.
99 ** Incremental search will now highlight all visible matches, making
100 it easier to anticipate where consecutive C-s or C-r will place the
101 point. If you want to disable the feature, set
102 `isearch-highlight-all-matches' to nil.
104 ** The "coding systems" feature now works even in an XEmacs compiled
105 without international (Mule) support. This means that for example
106 XEmacs can recognize newline convention used by the file you are
109 ** You can now use the buffer tabs to switch between buffers. The
110 tabs are located between the toolbar and the uppermost window, in a
111 location called "gutter". If you dislike the buffer tabs, you can
112 disable them by customizing `gutter-buffers-tab-visible-p', or by
113 placing this in your .emacs:
115 (set-gutter-element-visible-p default-gutter-visible-p 'buffers-tab nil)
117 You can change the location of the gutter with
118 `set-default-gutter-position', however currently only MS-Windows
119 supports tab widgets with orientations other than vertical.
121 ** Kill and yank now interact with the clipboard by default under
122 Windows. This was done by changing the default value of
123 `interprogram-cut-function' and `interprogram-paste-function'. You
124 can get the old behavior by setting these to nil, and there is an
125 option on the options menu to do this.
127 ** When you press RET at a minibuffer prompt that provides a default
128 value, the value is stored in history instead of an empty line. Also,
129 you can now edit the default value by pressing the down arrow,
130 accessing the logical "future" value. Not all minibuffer prompts have
131 yet been converted to support this feature.
133 ** International keysyms are now supported under X. This means that
134 XEmacs running under Mule will automatically recognize the keysym
135 `scaron' to be the lower-case `s' with caron in the Latin 2 character
136 set. (Specifically, it will bind the keysym to `self-insert' and
137 augment its `ascii-character' property.) This is very useful with
138 XFree under European locales as shipped by recent Linux distributions.
139 If XEmacs is compiled without Mule support, the feature still works,
140 but it is unaware of different character sets -- it unconditionally
141 sets the `ascii-character' property to values in the [160, 256) range.
143 ** The rectangle functions have been almost completely rewritten in
144 order to avoid inserting undesirable spaces, notably at the end of
145 lines. Two typical examples of the old behavior were
146 `string-rectangle', which filled all lines up to the right side of the
147 rectangle, and `clear-rectangle', which filled even empty lines up to
148 the left side. All functions have been rewritten to avoid inserting
149 unwanted spaces, and an optional prefix now allows them to behave the
152 Also, the behavior of `string-rectangle' is now compliant with
153 `pending-delete-mode': if this mode is active, then the string
154 replaces the region rectangle. Otherwise, the command does not delete
155 or overwrite any existing text. For those who want that feature but do
156 not use pending-delete-mode, a new function, `replace-rectangle', is
159 As a side effect, the FORCE argument to `move-to-column' now
160 understands the special value `coerce', which means that the line
161 should not be filled if it is too short to reach the desired column.
163 ** Customize now supports adding comments about your face and variable
164 settings using a new menu entry. Comments for variables can also be
165 assigned by calling `customize-set-(value|variable)' with a prefix
168 ** XEmacs now locates the early package hierarchies at
169 ~/.xemacs/mule-packages/ and ~/.xemacs/xemacs-packages/. Previously,
170 the early packages were located in ~/.xemacs/.
172 ** You can now create "indirect buffers", like in GNU Emacs. An
173 indirect buffer shares its text with another buffer ("base buffer"),
174 but has its own major mode, local variables, extents, and narrowing.
175 An indirect buffer has a name of its own, distinct from those of the
176 base buffer and all other buffers. An indirect buffer cannot itself
177 be visiting a file (though its base buffer can be). The base buffer
178 cannot itself be indirect.
180 Use (make-indirect-buffer BASE-BUFFER NAME) to make an indirect buffer
181 named NAME whose base is BASE-BUFFER. If BASE-BUFFER is itself an
182 indirect buffer, its base buffer is used as the base for the new
185 You can make an indirect buffer current, or switch to it in a window,
186 just as you would a non-indirect buffer.
188 The function `buffer-base-buffer' returns a buffer's base buffer or
189 nil, if given an ordinary (non-indirect) buffer. The function
190 `buffer-indirect-children' returns a list of the indirect children of
193 ** User names following the tilde character can now be completed at
194 file name prompts; e.g. `C-x C-f ~hni<TAB>' will complete to
195 `~hniksic/'. To make this operation faster, a cache of user names is
196 maintained internally.
198 The new primitives available for this purpose are functions named
199 `user-name-completion' and `user-name-all-completions'.
201 ** XEmacs can now play sound using Enlightenment Sound Daemon (ESD).
202 It will try NAS first, then ESD, then playing native sound directly.
204 ** X-Face support is now available under MS-Windows.
205 If an X-Face library built under MS-Windows is available then XEmacs
206 will use this at build time.
208 ** The font-menu is now available under MS-Windows.
210 ** MS-Windows support for selection is now much more robust.
212 Generally selection should now do what you would expect under
213 MS-Windows: the middle mouse button will paste your current selection
214 or the clipboard; conversions from different types of selection to the
215 clipboard can be made; the kill-ring and friends will be updated as
218 The only thing selection doesn't do is set the clipboard automatically
219 as this would break the MS-Windows model. If you want this behavior
220 then set `selection-sets-clipboard' to t.
222 ** Motif selection support is now more correct (but slower) in its behaviour.
224 Changes have been made to allow correct operation of cut/copy/paste
225 operations between native widgets and XEmacs buffers. However, this
226 can lead to a lot of X traffic which slows down the performance of
227 `C-k'. If you want the old behaviour then set
228 `x-selection-strict-motif-ownership' to nil.
230 ** Mail spool locking now works correctly.
231 XEmacs has always come with a little auxiliary program, movemail,
232 which moves mail out of the system's spool area into user storage. To
233 coordinate between XEmacs, the mail delivery agent, and other mail
234 user agents, movemail needs to properly lock the spool file before
235 moving it. Movemail now correctly respects the --mail-locking option
236 to configure. Moreover, movemail's locking behavior can be specified
237 at run-time, via a new command-line option -m to movemail, or through
238 the environment variable EMACSLOCKMETHOD.
240 When installing XEmacs, make sure you configure it according to your
241 environment's mail spool locking conventions. When you're using a
242 binary kit, set the `mail-lock-method' variable at startup, or the
243 EMACSLOCKMETHOD environment variable.
245 ** Indentation no longer indents comments that begin at column zero.
246 This makes it easy to deal with commented out regions of code.
248 ** Init file changes.
250 *** XEmacs now supports a `~/.xemacs/init.el' startup file. If
251 it exists, XEmacs will prefer it over `.emacs' and `.emacs.el'. The
252 file may be byte-compiled as `~/.xemacs/init.elc'.
254 If present, the `~/.xemacs/' directory may contain startup files for
255 XEmacs packages that support it.
257 *** Init file in your home directory may be called `.emacs.el'.
259 Like in GNU Emacs 20.4 and on, you can now name the XEmacs init file
260 located in your home directory `.emacs.el'. Formerly the name had to
261 be `.emacs'. If you use the name `.emacs.el', you can byte-compile
262 the file in the usual way.
264 If both `.emacs' and `.emacs.el' exist, the latter file is the one
267 *** New command-line switches -user-init-file and -user-init-directory.
268 These can be used to specify alternate locations for what is normally
269 ~/.emacs and ~/.xemacs.
271 Moreover, the `-user <user>' command-line option (which used to only
272 work in unpredictable ways) is now equivalent to `-user-init-file
273 ~<user>/.xemacs/init.el -user-init-directory ~<user>/.xemacs', or
274 `-user-init-file ~<user>/.emacs -user-init-directory ~<user>/.xemacs',
275 whichever init file comes first.
277 *** Custom file will move to ~/.xemacs/custom.el.
279 Whereas customize settings were formerly stored in the regular init
280 file, XEmacs now prefers them to be in a separate file
281 `~/.xemacs/custom.el', completely under automatic control. This
282 change goes with the migration of the init file, and XEmacs offers
283 automatic migration upon startup.
285 ** New variable `mswindows-alt-by-itself-activates-menu'.
286 If you set this variable to nil then pressing and releasing the Alt
287 key under MS-Windows will no longer activate the menubar. The default
288 is t. This is not to be confused with `menu-accelerator-enabled',
289 which enables the use of Alt+<Letter> accelerators to invoke the
292 ** Pixel-based scrolling has been implemented.
293 By default this will attempt to scroll in increments equal to the
294 height of the default face. Set `window-pixel-scroll-increment' to
295 modify this behavior.
297 ** Operation progress can be displayed using graphical widgets.
298 See `progress-feedback' for details. This support has been switched
299 on by default for font-lock and some web browsing functions. If you
300 do not like this behavior set `progress-feedback-use-echo-area'.
302 ** The PostgreSQL Relational Database Management System is now supported.
303 It is now possible to build XEmacs so that the programming interface
304 to the PostgreSQL RDBMS (libpq) is available in XEmacs Lisp.
305 Supported versions of PostgreSQL are 6.5.3 (earlier versions may work,
306 but have not been tested) and 7.0-beta1.
308 ** Help functions (e.g. `C-h f') now know how to print macro argument
309 lists. If your macro definition included an argument list for the
310 sake of help output, you no longer need to do that.
314 *** Windows 1251 code page is now supported as coding system
317 *** Czech, Thai, Cyrillic-KOI8, Vietnamese, Ethiopic support now
320 *** The appropriate characters in Latin 3 and Latin 4 character sets
321 are correctly defined as words.
323 *** The default coding-priority-list is now safer. This means that if
324 you have no language environment set, Mule no longer automatically
325 recognizes ISO 2022 escapes in your files. This makes editing binary
330 *** In DOS, etags looks for file.cgz if it cannot find file.c.
332 *** New option --ignore-case-regex is an alternative to --regex. It is now
333 possible to bind a regexp to a language, by prepending the regexp with
334 {lang}, where lang is one of the languages that `etags --help' prints
335 out. This feature is useful especially for regex files, where each
336 line contains a regular expression. The manual contains details.
338 *** In C and derived languages, etags creates tags for function
339 declarations when given the --declarations option.
341 *** In C++, tags are created for "operator". The tags have the form
342 "operator+", without spaces between the keyword and the operator.
344 *** New language Ada: tags are functions, procedures, packages, tasks, and
347 *** In Fortran, procedure is no longer tagged.
349 *** In Java, tags are created for "interface".
351 *** In Lisp, "(defstruct (foo", "(defun (operator" and similar constructs
354 *** In Perl, the --globals option tags global variables. my and local
355 variables are tagged.
357 *** New language Python: def and class at the beginning of a line are tags.
359 *** .ss files are Scheme files, .pdb is Postscript with C syntax, .psw is
363 * Lisp and internal changes in XEmacs 21.4
364 ==========================================
366 ** A new portable dumper is available for beta testing.
368 Olivier Galibert has written a portable dumper for XEmacs, based on
369 initial work by Kyle Jones. To perform even the most basic editor,
370 XEmacs requires some amount of Lisp code to be loaded. To avoid
371 repeating the expensive loading process at every startup, XEmacs is
372 built in a special way. Its C sources link into an executable called
373 `temacs', which loads the bootstrap Lisp code and uses a special
374 "unexec" call to dump the resulting memory image into a proper
375 `xemacs' executable on disk. The unexec() process is hard to
376 implement correctly and makes XEmacs very hard to port to new
377 operating systems, or even to new releases of old systems.
379 The new portable dumper uses a different approach to dumping: instead
380 of dumping full-fledged executable, it only dumps out the initialized
381 data structures (both Lisp and C) into an external file. A normally
382 running XEmacs only needs to mmap that file and relocate a bit to get
383 to the initialized data. In that scheme, there is no difference
384 between `temacs' and `xemacs'.
386 Unfortunately, the portable dumper has not been completely finished
387 for this release, and will not be used by default. However, if you
388 wish to experiment with it, or if you need to compile XEmacs on a new
389 and unsupported platform, you can test it by configuring XEmacs with
392 ** Much effort has been invested to make XEmacs Lisp faster:
394 *** Many basic lisp operations are now faster.
395 This is especially the case when running a Mule-enabled XEmacs.
397 A general overhaul of the lisp engine should produce a speedup of 1.4
398 in a non-Mule XEmacs, and 2.1 in a Mule XEmacs. These numbers were
399 obtained running `(byte-compile "simple.el")', which should be a
400 pretty typical test of "pure" Lisp.
402 *** Lisp hash tables have been re-implemented. The Common Lisp style
403 hash table interface has been made standard, and moved from cl.el into
404 fast C code (See the section on hash tables in the XEmacs Lisp
405 Reference). A speedup factor of 3 can be expected with code that
406 makes intensive use of hash tables.
408 *** The garbage collector has been tuned, leading to a speedup of
411 *** The byte-compiler and the byte-optimizer have been tuned to
412 produce better code in many small ways.
414 *** The family of functions that iterate over lists, like `memq', and
415 `rassq', have been made a little faster (typically 1.3).
417 *** Lisp function calls are faster, by approximately a factor of two.
418 However, defining inline functions (via defsubst) still makes sense
421 *** Finally, a few functions have had dramatic performance
422 improvements. For example, `(last long-list)' is now 30 times faster.
424 Of course, your mileage will vary.
426 Many operations do not see any improvement. Surprisingly, running
427 (font-lock-fontify-buffer) does not use the Lisp engine much at all.
428 Speeding up your favorite slow operation is an excellent project to
429 improve XEmacs. Don't forget to profile!
431 ** Native widgets can be displayed in buffers.
433 The glyph system has been extended to allow the display of glyphs that
434 are implemented as native window-system widgets. Thus you can embed
435 buttons, scrollbars, combo boxes, edit fields and progress gauges in a
436 buffer. As a side effect subwindow support now works once again.
438 All of this is still fairly experimental and there is no
439 documentation. The current APIs might change in a future version of
440 XEmacs. Some widgets are only available under MS-Windows. See the
441 file glyphs-test.el in the XEmacs src distribution for examples of
444 The buffers-tab functionality and progress gauge have been implemented
447 ** A new Windows installer, netinstall ported from Cygwin.
449 Nearly complete automation of the XEmacs install process from
450 ftp.xemacs.org. Includes selection of Lisp packages to install, etc.
452 ** Syntax tables may now be specified for a part of a buffer by
453 attaching the `syntax-table' property to an extent. For compatibility
454 with GNU Emacs, you may use the text-property interface to achieve the
457 ** Case translation now supports international characters.
459 *** Instead of being lists of 256-character strings, case tables are
460 now opaque objects. The interface to access them is almost the same,
461 except it now works for international characters, and you can set the
462 case pairs using `put-case-table-pair'. `set-case-table' and friends
463 still support the old list/string based interface for backward
466 *** As a consequence of this change, functions `downcase' and `upcase'
467 as well as all the case-transformation commands now work with
468 non-ASCII characters. Built-in tables cover all the Latin character
469 sets that we support. If your language has a distinction between
470 upper and lower case that is not handled by XEmacs/Mule, please let us
473 *** The code that implements case-insensitive search has been modified
474 to respect the case table settings. This also applies to regexp
477 ** Values of variables `user-init-file' and `user-init-directory' are
478 now absolute file/directory names. Previously, both variables used to
479 be relative to `(concat "~" init-file-user)'. This turned out to be
480 too complicated for most packages (and some core Lisp files) to use
481 correctly. Also, the `init-file-user' variable has been obsoleted in
484 The user-visible options like `-u' have not changed their behavior.
486 ** XEmacs finally has an automated test suite!
487 Although this is not yet very sophisticated, it is already responsible
488 for several important bug fixes in XEmacs. To try it out, simply use
489 the makefile target `make check' after building XEmacs.
491 ** Hash tables have been reimplemented.
492 As was pointed out above, the standard interface to hash tables is now
493 the Common Lisp interface, as described in Common Lisp, the Language
494 (CLtL2, by Steele). The older interface (functions with names
495 containing the phrase `hashtable') will continue to work, but the
496 preferred interface now has names containing the phrase `hash-table'.
498 Here's the executive overview: create hash tables using
499 make-hash-table, and use gethash, puthash, remhash, maphash and
500 clrhash to manipulate entries in the hash table. See the (updated)
501 Lisp Reference Manual for details.
503 ** Lisp code handles circular lists much more robustly.
504 Many basic lisp functions used to loop forever when given a circular
505 list, expecting you to C-g (quit) out of the loop. Now this is more
506 likely to trigger a `circular-list' error. Printing a circular list
507 now results in something like this:
509 (let ((x (cons 'foo 'foo)))
512 => (foo ... <circular list>)
514 An extra bonus is that checking for circularities is not just
515 friendlier, but actually faster than checking for C-g.
517 ** Functions for decoding base64 encoding are now available; see
518 `base64-encode-region', `base64-encode-string', `base64-decode-region'
519 and `base64-decode-string'.
521 ** The functions `read-string', `read-expression', `eval-minibuffer',
522 `read-variable', `read-command', `read-function', `read-number',
523 `read-shell-command', `read-from-minibuffer', and `completing-read'
524 now take an additional argument which specifies the default value. If
525 this argument is non-nil, it should be a string; that string is used
528 * It is returned if the user enters empty input.
529 * It is available as the logical "future" entry, by pressing the down
534 *** The LDAP interface now consists of two layers, a low-level layer
535 that closely matches the LDAP C API, and a more convenient
536 higher-level set of functions.
538 *** The low-level functions that used to be named *-internal are now
539 named more simply: `ldap-open', `ldap-close', `ldap-search-basic',
540 `ldap-add', and `ldap-modify'. They should be used directly for very
541 specific purposes (such as multiple operations on a connection) only.
543 *** The higher-level functions provide a more convenient way to access
544 LDAP directories hiding the subtleties of handling the connection,
545 translating arguments and ensuring compliance with LDAP
546 internationalization rules and formats (currently partly implemented
547 only.) This layer provides atomic operations for searches,
548 modification, addition and deletion of multiple entries at once:
549 `ldap-search-entries', `ldap-add-entries', `ldap-delete-entries', and
550 `ldap-modify-entries'.
552 *** To maintain compatibility with previous code, the now obsolete
553 function `ldap-search' is now merely a wrapper that calls either
554 `ldap-search-basic' or `ldap-search-entries'. Please don't use the
555 `ldap-search' function in your new programs -- a direct call to one of
556 the two replacements is more efficient and unambiguous.
558 ** The arguments to `locate-file' are now more Lisp-like. As before,
561 (locate-file FILENAME PATH-LIST &optional SUFFIXES MODE)
563 Except that SUFFIXES are now a list of strings instead of a single,
564 colon-separated string. MODE is now a symbol or a list of symbols
565 (symbols `exists', `executable', `writable', and `readable' are
566 supported) instead of an integer code. See the documentation for
567 details. Of course, the old form is still accepted for backward
570 Several bugs in locate-file have been fixed, most notably its failure
571 to call expand-file-name on elements of PATH-LIST. Because of that
572 elements of load-path of the form "~/..." used to not work.
573 locate-file is now guaranteed to expand files during its course of
576 ** `translate-region' has been improved in several ways. Its TABLE
577 argument used to be a 256-character string. In addition to this, it
578 can now also be a vector or a char-table, which makes the function
579 useful for Mule, which it wasn't. If TABLE is a vector or a generic
580 char-table, you can map characters to strings instead of to other
581 characters. For instance:
583 (let ((table (make-char-table 'generic)))
584 (put-char-table ?a "the letter a" table)
585 (put-char-table ?b "" table)
586 (put-char-table ?c ?\n table)
587 (translate-region (point-min) (point-max) table))
589 ** The new form `ignore-file-errors', similar to `ignore-errors' may
590 be used as a short-hand for condition-case when you wish to ignore
591 file-related error. For example:
593 (ignore-file-errors (delete-file "foo"))
595 ** The first argument to `intern-soft' may now also be a symbol, like
596 with `unintern'. If given a symbol, `intern-soft' will look for that
597 exact symbol rather than for any string. This is useful when you want
598 to check whether a specific symbol is interned in an obarray, e.g.:
603 (intern-soft (make-symbol "foo"))
606 ** The `keywordp' function now returns non-nil only on symbols
607 interned in the global obarray. For example:
609 (keywordp (intern ":foo" [0]))
611 (keywordp (intern ":foo")) ; The same as (keywordp :foo)
614 This behavior is compatible with other code which treats symbols
615 beginning with colon as keywords only if they are interned in the
616 global obarray. `keywordp' used to wrongly return t in both above
619 ** The function `replace-in-string' has been rewritten to use
620 `replace-match'. This not only makes it much faster, but adds all the
621 features of `replace-match'.
623 ** New variables `this-command-properties' and
624 `last-command-properties' are now available for communication between
625 consecutive commands. Commands should use these to communicate with
626 the pre/post-command hooks, subsequent commands, wrapping commands,
627 etc. in preference to looking at and/or setting `this-command'.
629 ** New functions `add-one-shot-hook' and `add-local-one-shot-hook' make
630 it possible to add a "one-shot" hook, which is to say a hook that runs
631 only once, and automatically removes itself after the first time it
634 ** The descriptor that specifies the text of a menu item can now be an
635 evaluated expression. This makes it parallel with other descriptors,
636 which can also be expressions.
639 * Changes in XEmacs 21.0
640 ========================
642 ** XEmacs has been unbundled into constituent installable packages.
643 See the Info documentation under "Packages" for more information.
644 See the file `etc/PACKAGES' in the distribution for a partial list of
645 packages available at the time of the 21.0 release.
647 ** XEmacs is now supported under Microsoft Windows 95/98 and Windows
648 NT operating systems. For starters, look at the XEmacs on Windows FAQ
649 at <URL:http://jagor.srce.hr/~hniksic/xemacs-on-windows-faq.txt>. To
650 discuss Windows-specific issues, subscribe to the mailing list at
651 <xemacs-nt-request@xemacs.org>.
653 ** XEmacs will now use `XEmacs' as its application class if it finds
654 any `XEmacs' resources in the resource database. Otherwise, it will
655 continue to use the `Emacs' class.
657 ** The options menu has been ported to Custom.
658 This means that each entry in the options menu acts as if you had customized
659 the corresponding variable by hand. ### WARNING: there is currently no
660 upgrading function to help you port your old options settings to the new
661 format. Consequently, if you want to modify the options for XEmacs 21, you
662 will have to set them all again through the menu, and remove the code loading
663 .xemacs-options from your .emacs.
665 ** When the Zmacs region is active, `M-x query-replace' and the other
666 replace commands now operate on the region contents only.
668 ** XEmacs now is able to choose X visuals and use private colormaps.
669 The '-visual <visualStr>' command line option or the '.EmacsVisual'
670 Xresource controls which visual XEmacs will use, and
671 '-privateColormap' or '.privateColormap' will force XEmacs to create a
672 private colormap for use. The syntax for the visual string is
673 "<visual><bitdepth>" where <visual> is one of 'StaticColor',
674 'TrueColor', 'GrayScale', 'PseudoColor' or 'DirectColor' and
675 <bitdepth> is the appropriate number of bits per pixel. If an invalid
676 or non-supported combination is entered, XEmacs attempts to find a happy
677 medium. The X creation mechanism will then determine if it needs to
678 create a colormap for use, or the presence of the private flags will
679 force it to create it.
681 ** The `imenu' package has been ported to XEmacs and is available as a
684 ** `echo-keystrokes' can now be a floating-point number, so that you
685 can set it to intervals shorter than one second.
687 (setq echo-keystrokes 0.1)
689 ** The new command `center-to-window-line' works like `recenter'
690 (bound to `C-l'), only it does not redisplay the whole display area.
692 ** The M-. command will now first search through exact tags matches,
693 and then through inexact matches, as one would expect.
695 ** The new variable `user-full-name' can be used to customize one's
696 name when using the Emacs mail and news reading facilities.
698 Normally, `user-full-name' is a function that returns the full name of
699 a user or UID, as specified by the system -- for instance,
700 (user-full-name "root") returns something like "Super-User". However,
701 when the function is called without arguments, it will return the
702 value of the `user-full-name' variable. The `user-full-name' variable
703 is initialized using the environment variable NAME and (failing that)
704 the user's system name.
706 The behavior of the `user-full-name' function with an argument
707 specified is unchanged.
709 ** The new command `M-x customize-changed-options' lets you customize
710 all the options whose default values have changed in recent Emacs
711 versions. You specify a previous Emacs version number as argument,
712 and the command creates a customization buffer showing all the
713 customizable options whose default values were changed since that
716 If you don't specify a particular version number argument, then the
717 customization buffer shows all the customizable options for which
718 Emacs versions of changes are recorded.
720 ** The new command `add-log-convert' can be used to convert the
721 old-style (pre-20.3) ChangeLog buffers to new style, for
722 consistency. A reminder: if you wish to revert to old-style
723 ChangeLogs instead, customize the value of `add-log-time-format'
726 ** The new command `zap-up-to-char' is now available. It is similar
727 to `zap-to-char', except that it does not delete the searched-for
728 character. It is not bound to a key by default.
730 ** You can now store a number into a register with `C-u NUMBER C-x r n'
731 REG, increment it by INC with `C-u INC C-x r + REG' (to increment by
732 one, omit C-u INC), and insert it in the buffer with `C-x r g REG'.
733 This is useful for writing keyboard macros.
735 ** The M-: command, when given a prefix argument, will now insert its
736 result to the current buffer.
738 ** The `C-h c' command, when given a prefix argument, will now insert
739 the message into the current buffer.
741 ** Horizontally split windows may now be dragged using the mouse.
742 Because of this, the dividers between vertical windows are always
743 visible. To turn it off, set `vertical-divider-always-visible-p' to
746 ** XEmacs/Mule (internationalization) changes.
748 *** Mule support now works on TTY's. Use `set-terminal-coding-system'
749 and `set-keyboard-coding-system' to specify the coding system of your
750 display and keyboard.
752 *** Egg/SJ3 input method is now officially supported. Quail and
753 Egg/Skk have been available through the generalized Leim since 20.3.
755 *** Localized Japanese menubars are available if XEmacs is built with
756 XFONTSET and either the X11 libraries are built with X_LOCALE defined
757 or the native C libraries support Japanese localization. This has
758 been available since 20.3, only it hasn't been announced before.
760 ** Jamie Zawinski's `gdb-highlight' extension is now distributed with
761 the `debug' package. gdb-highlight makes most objects printed in a
762 gdb buffer be mouse-sensitive: as text shows up in the buffer, it is
763 parsed, and objects which are recognized have context-sensitive
764 commands attached to them. To use it, add the following to `.emacs':
766 (add-hook 'gdb-mode-hook (lambda () (require 'gdb-highlight)))
768 ** The package popper.el is now included in the edit-utils package.
769 It has been greatly enhanced with respect to the one once included
770 with the ilisp package and should work well under XEmacs 21.0.
774 *** Like the old 'gnudoit' program. Gnuclient -batch now can read from stdin.
776 *** Gnuclient -batch no longer breaks off the output at the first LF.
780 *** Multiline macros are now handled, both as they affect indentation,
781 and as recognized syntax. New syntactic symbol cpp-macro-cont is
782 assigned to second and subsequent lines of a multiline macro
785 *** A new style "user" which captures all non-hook-ified
786 (i.e. top-level) .emacs file variable setings and customizations.
787 Style "cc-mode" is an alias for "user" and is deprecated. "gnu" style
788 is still the default however.
790 *** "java" style now conforms to Sun's JDK coding style.
792 *** There are new commands c-beginning-of-defun, c-end-of-defun which
793 are alternatives which you could bind to C-M-a and C-M-e if you prefer
794 them. They do not have key bindings by default.
796 *** New and improved implementations of M-a (c-beginning-of-statement)
797 and M-e (c-end-of-statement).
799 *** C++ namespace blocks are supported, with new syntactic symbols
800 namespace-open, namespace-close, and innamespace.
802 *** File local variable settings of c-file-style and c-file-offsets
803 makes the style variables local to that buffer only.
805 *** New indentation functions c-lineup-close-paren,
806 c-indent-one-line-block, c-lineup-dont-change.
808 *** Improvements (hopefully!) to the way CC Mode is loaded. You
809 should now be able to do a (require 'cc-mode) to get the entire
810 package loaded properly for customization in your .emacs file. A new
811 variable c-initialize-on-load controls this and is t by default.
813 ** In Text mode, now only blank lines separate paragraphs.
814 This makes it possible to get the full benefit of Adaptive Fill mode
815 in Text mode, and other modes derived from it (such as Mail mode).
816 TAB in Text mode now runs the command indent-relative; this makes a
817 practical difference only when you use indented paragraphs.
819 As a result, the old Indented Text mode is now identical to Text mode,
820 and is an alias for it.
822 If you want spaces at the beginning of a line to start a paragraph,
823 use the new mode, Paragraph Indent Text mode.
825 ** Changes to Gnus, the XEmacs newsreader.
827 *** New functionality for using Gnus as an offline newsreader has been
828 added. A plethora of new commands and modes have been added. See the
829 Gnus manual for the full story.
831 *** The nndraft backend has returned, but works differently than
832 before. All Message buffers are now also articles in the nndraft
833 group, which is created automatically.
835 *** `gnus-alter-header-function' can now be used to alter header
838 *** `gnus-summary-goto-article' now accept Message-ID's.
840 *** A new Message command for deleting text in the body of a message
841 outside the region: `C-c C-v'.
843 *** You can now post to component group in nnvirtual groups with
846 *** `nntp-rlogin-program' -- new variable to ease customization.
848 *** `C-u C-c C-c' in `gnus-article-edit-mode' will now inhibit
849 re-highlighting of the article buffer.
851 *** New element in `gnus-boring-article-headers' -- `long-to'.
853 *** `M-i' symbolic prefix command. See the section "Symbolic
854 Prefixes" in the Gnus manual for details.
856 *** `L' and `I' in the summary buffer now take the symbolic prefix
857 `a' to add the score rule to the "all.SCORE" file.
859 *** `gnus-simplify-subject-functions' variable to allow greater
860 control over simplification.
862 *** `A T' -- new command for fetching the current thread.
864 *** `/ T' -- new command for including the current thread in the
867 *** `M-RET' is a new Message command for breaking cited text.
869 *** \\1-expressions are now valid in `nnmail-split-methods'.
871 *** The `custom-face-lookup' function has been removed.
872 If you used this function in your initialization files, you must
873 rewrite them to use `face-spec-set' instead.
875 *** Cancelling now uses the current select method. Symbolic prefix
876 `a' forces normal posting method.
878 *** New command to translate M******** sm*rtq**t*s into proper text
881 *** For easier debugging of nntp, you can set `nntp-record-commands'
884 *** nntp now uses ~/.authinfo, a .netrc-like file, for controlling
885 where and how to send AUTHINFO to NNTP servers.
887 *** A command for editing group parameters from the summary buffer
890 *** A history of where mails have been split is available.
892 *** A new article date command has been added -- `article-date-iso8601'.
894 *** Subjects can be simplified when threading by setting
895 `gnus-score-thread-simplify'.
897 *** A new function for citing in Message has been added --
898 `message-cite-original-without-signature'.
900 *** `article-strip-all-blank-lines' -- new article command.
902 *** A new Message command to kill to the end of the article has
905 *** A minimum adaptive score can be specified by using the
906 `gnus-adaptive-word-minimum' variable.
908 *** The "lapsed date" article header can be kept continually
909 updated by the `gnus-start-date-timer' command.
911 *** Web listserv archives can be read with the nnlistserv backend.
913 *** Old dejanews archives can now be read by nnweb.
915 *** Byte-compilation of user-specs now works under XEmacs.
917 ** The `dir' files are no longer essential for functioning of the Info
918 subsystem. If the `dir' file does not exist in an Info directory, the
919 relevant information will be generated on-the-fly.
921 This behavior can be customized, look for `Info-auto-generate-directory'
922 and `Info-save-auto-generated-dir' in the `info' customization group.
925 * Lisp and internal changes in XEmacs 21.0
926 ==========================================
928 ** It is now possible to build XEmacs with support for 31-bit Lisp
929 integers (normally, Lisp integers are only 28 bits wide on 32-bit
930 machines.) Configure with --use-minimal-tagbits to test. With this
931 change, the maximum buffer size on 32-bit machines is increased from
932 128M to 1G. This setting will be made default in a future XEmacs
935 ** Specifier changes.
937 *** When instantiating a specifier, the window locale now has a higher
938 precedence than the buffer locale. This is because the window locale
939 is more specific than the buffer locale.
941 *** The new macro `let-specifier' can be used to temporarily add
942 specifications to specifiers. See the documentation for details.
944 *** The new specifiers `vertical-scrollbar-visible-p' and
945 `horizontal-scrollbar-visible-p' may be used to control scrollbar
946 visibility. Previously, the only way to remove a scrollbar was to set
947 its size to 0. This method is still supported for backward
950 *** The new specifiers `scrollbar-on-left-p' and `scrollbar-on-top-p'
951 may be used to control the position of the vertical and horizontal
952 toolbar. Previously, their position could be changed only through the
955 *** The new draggable vertical dividers between windows may be turned
956 off using the `vertical-divider-always-visible-p' specifier. When
957 this is set to nil, the vertical dividers between windows are shown
958 only when needed, and they are not draggable.
960 Other properties of the vertical dividers may be controlled using
961 `vertical-divider-shadow-thickness', `vertical-divider-line-width' and
962 `vertical-divider-spacing' specifiers, which see.
964 ** Frame focus management changes.
966 *** When the variable focus-follows-mouse is non-nil, `select-frame'
967 no longer permanently selects a different frame. The frame selection
968 is temporary and is reverted when the current command terminates, much
969 like the buffer selected by `set-buffer'. This is the same as in FSF
972 *** The new function `focus-frame' sets the window system focus to
973 FRAME (and selects it), regardless of the value of
974 `focus-follows-mouse'. Doing this is not well behaved, so be
975 absolutely sure that you want this.
977 The code that uses `select-frame' only to get the window manager focus
978 should be changed to use `set-frame-focus' instead, so that they keep
979 working when `focus-follows-mouse' is non-nil.
981 *** The special forms `save-selected-frame' and `with-selected-frame'
982 can now be used to temporarily change selected frame.
984 *** The behavior of `other-frame' command (`C-x 5 o') is unaffected by
987 ** The function `select-window' now has an optional second argument
988 NORECORD which if non-nil inhibits the recording of a buffer change.
990 ** The function `vertical-motion' now correctly handles the second,
991 optional WINDOW argument. A new third argument PIXELS, if non-nil,
992 indicates that the returned motion should be in pixels.
994 ** The new function `vertical-motion-pixels' is similar to
995 vertical-motion but takes as input a vertical motion in pixels.
997 ** The new functions window-text-area-pixel-{width,height,edges} can
998 be used to obtain information about the text-displaying area of a
1001 ** The new functions `shrink-window-pixels' and `enlarge-window-pixels'
1002 can be used to adjust the size of a window by a pixel amount.
1004 ** The new function `window-displayed-text-pixel-height' can be used
1005 to determine the height of the text actually displayed in a window.
1007 ** The arithmetic comparison functions <, >, =, /= now accept a
1008 variable number of arguments.
1010 This means that if you want to test whether A < B < C, you can write
1011 it as (< A B C) instead of (and (< A B) (< B C)). Likewise,
1012 (apply #'> LIST) now tests if LIST is monotonously increasing -- and
1015 ** The XEmacs hashtables now have a consistent read/print syntax.
1016 This means that a hashtable will be readably printed in a
1017 structure-like form:
1019 #s(hashtable size 2 data (key1 value1 key2 value2))
1021 When XEmacs reads this form, it will create a new hashtable according
1022 to description. This allows you to easily dump hashtables to files
1023 using `prin1', and read them back in using `read'.
1025 If `print-readably' is non-nil, a more relaxed syntax is used; for
1028 #<hashtable size 2/13 data (key1 value1 key2 value2) 0x874d>
1030 ** It is now possible to build XEmacs with LDAP support.
1031 You will need to install a LDAP library first. The following have
1033 - LDAP 3.3 from the University of Michigan
1034 (get it from <URL:http://www.umich.edu/~dirsvcs/ldap/>)
1035 - OpenLDAP 1.0.3 from the OpenLDAP Foundation
1036 (get it from <URL:http://www.openldap.org/>)
1037 - LDAP SDK 1.0 from Netscape Corp.
1038 (get it from <URL:http://developer.netscape.com/>)
1040 ** When profiling is in effect, a call-count of all recorded functions
1041 is now calculated. This information is stored in
1042 `call-count-profile-table', and is utilized by `profile-results' as
1043 well as the new command `profile-call-count-results'.
1045 ** It is now an error to change the value of a symbol whose name
1046 starts with a colon, if it is interned in the standard obarray.
1048 However, setting such a symbol to its proper value, which is that
1049 symbol itself, is not an error. This is for the sake of programs that
1050 support pre-19.12 XEmacs and pre-20 GNU Emacs by explicitly setting
1051 these variables to themselves.
1053 ** The `concat' function no longer accepts integer arguments.
1055 ** The new function `string' concatenates all its argument characters
1056 and returns the resulting string. This is consistent with other
1057 functions, like `list', `vector', etc.
1059 ** The function `temp-directory' is now available to return the
1060 directory to store temporary files. On Unix this will be obtained
1061 from TMPDIR, defaulting to `/tmp'.
1063 ** The function load-average now accepts an optional argument
1064 USE-FLOATS. If it is non-nil, the load average values are returned as
1065 floating point numbers, rather than as integers to be divided by 100.
1067 ** The `make-event' function now supports the TYPE and PLIST
1068 arguments, which can be used to create various events from Lisp. See
1069 the documentation for details.
1071 ** `function-interactive' is a new function that returns the
1072 interactive specification of a funcallable object.
1074 ** The new `lmessage' function allows printing of a formatted message
1075 with a particular label.
1077 (lmessage 'progress "Processing... %d" counter)
1079 This function is more convenient than `display-message' because it
1080 automatically applies `format' to its arguments.
1082 ** The new `lwarn' function, analogous to `lmessage', allows printing
1083 a formatted warning, with a non-default CLASS or LABEL.
1085 ** The new function `split-path' can now be used to explode the
1086 components of a colon-separated search path into a list.
1088 (split-path "foo:bar")
1091 ** Specifiers and symbols whose value is a specifier are now allowed
1092 as modeline specifications.
1094 ** defcustom now accepts the keyword `:version'. Use this to specify
1095 in which version of Emacs a certain variable's default value changed.
1098 (defcustom foo-max 34 "*Maximum number of foo's allowed."
1103 This information is used to control the customize-changed-options
1106 ** The line number tracking in modeline is now efficient, even for
1107 very large buffers. This is achieved by caching the line numbers of
1108 recent buffer positions, and reusing them. This cache is used only in
1109 the buffers where `line-number-mode' is in effect.
1111 ** When the new GNU Malloc aka Doug Lea Malloc is available, it will
1112 be used. This should result in better performance on Linux systems
1115 ** The code XEmacs uses to assemble its various paths into the
1116 directory hierarchy has been rewritten to support the package system.
1117 Look under "Startup Paths" in the Info documentation for more
1120 *** site-lisp is no longer part of the load-path by default.
1121 Its use is deprecated, but you can specify --with-site-lisp=yes at the
1122 configure command line to get it back.
1124 *** `Info-default-directory-list' is now obsolete. If you want to
1125 change the path which XEmacs uses to search for info files, set
1126 `Info-directory-list' instead.
1129 * For older news, see the file ONEWS.