1 GNU Emacs NEWS -- history of user-visible changes.
3 Copyright (C) 2014-2016 Free Software Foundation, Inc.
4 See the end of the file for license conditions.
6 Please send Emacs bug reports to bug-gnu-emacs@gnu.org.
7 If possible, use M-x report-emacs-bug.
9 This file is about changes in Emacs version 25.
11 See file HISTORY for a list of GNU Emacs versions and release dates.
12 See files NEWS.24, NEWS.23, NEWS.22, NEWS.21, NEWS.20, NEWS.19, NEWS.18,
13 and NEWS.1-17 for changes in older Emacs versions.
15 You can narrow news to a specific version by calling 'view-emacs-news'
16 with a prefix argument or by typing C-u C-h C-n.
19 +++ indicates that all necessary documentation updates are complete.
20 (This means all relevant manuals in doc/ AND lisp doc-strings.)
21 --- means no change in the manuals is needed.
22 When you add a new item, use the appropriate mark if you are sure it applies,
23 otherwise leave it unmarked.
26 * Installation Changes in Emacs 25.2
28 ** The new option 'configure --enable-gcc-warnings=warn-only' causes
29 GCC to issue warnings without stopping the build. This behavior is
30 now the default in developer builds. As before, use
31 '--disable-gcc-warnings' to suppress GCC's warnings, and
32 '--enable-gcc-warnings' to stop the build if GCC issues warnings.
35 ** The Emacs server now has socket-launching support. This allows
36 socket based activation, where an external process like systemd can
37 invoke the Emacs server process upon a socket connection event and
38 hand the socket over to Emacs. Emacs uses this socket to service
39 emacsclient commands. This new functionality can be disabled with the
40 configure option '--disable-libsystemd'.
42 ** New configure option '--disable-build-details' attempts to build an
43 Emacs that is more likely to be reproducible; that is, if you build
44 and install Emacs twice, the second Emacs is a copy of the first.
45 Deterministic builds omit the build date from the output of the
46 emacs-version and erc-cmd-SV functions, and the leave the following
47 variables nil: emacs-build-system, emacs-build-time,
50 ** Emacs no longer works on IRIX. We expect that Emacs users are not
51 affected by this, as SGI stopped supporting IRIX in December 2013.
54 * Startup Changes in Emacs 25.2
57 * Changes in Emacs 25.2
60 ** 'find-library-name' will now fall back on looking at 'load-history'
61 to try to locate libraries that have been loaded with an explicit path
65 ** Faces in 'minibuffer-prompt-properties' no longer overwrite properties
66 in the text in functions like 'read-from-minibuffer', but instead are
67 added to the end of the face list. This allows users to say things
68 like '(read-from-minibuffer (propertize "Enter something: " 'face 'bold))'.
71 ** The new variable 'extended-command-suggest-shorter' has been added
72 to control whether to suggest shorter 'M-x' commands or not.
75 ** icomplete now respects 'completion-ignored-extensions'.
78 ** Non-breaking hyphens are now displayed with the 'nobreak-hyphen'
79 face instead of the 'escape-glyph' face.
82 ** 'C-x h' ('mark-whole-buffer') will now avoid marking the prompt
86 ** 'find-library' now takes a prefix argument to pop to a different
89 ** 'find-library', 'help-function-def' and 'help-variable-def' now run
90 'find-function-after-hook'.
93 ** 'process-attributes' on Darwin systems now returns more information.
96 ** Several accessors for the value returned by 'file-attributes'
97 have been added. They are: 'file-attribute-type',
98 'file-attribute-link-number', 'file-attribute-user-id',
99 'file-attribute-group-id', 'file-attribute-access-time',
100 'file-attribute-modification-time',
101 'file-attribute-status-change-time', 'file-attribute-size',
102 'file-attribute-modes', 'file-attribute-inode-number', and
103 'file-attribute-device-number'.
106 ** The new function 'buffer-hash' computes a fast, non-consing hash of
110 ** 'fill-paragraph' no longer marks the buffer as changed unless it
111 actually changed something.
114 ** The locale language name 'ca' is now mapped to the language
115 environment 'Catalan', which has been added.
118 ** 'align-regexp' has a separate history for its interactive argument.
119 'align-regexp' no longer shares its history with all other
120 history-less functions that use 'read-string'.
123 ** The networking code has been reworked so that it's more
124 asynchronous than it was (when specifying :nowait t in
125 'make-network-process'). How asynchronous it is varies based on the
126 capabilities of the system, but on a typical GNU/Linux system the DNS
127 resolution, the connection, and (for TLS streams) the TLS negotiation
128 are all done without blocking the main Emacs thread. To get
129 asynchronous TLS, the TLS boot parameters have to be passed in (see
130 the manual for details).
132 Certain process oriented functions (like 'process-datagram-address')
133 will block until socket setup has been performed. The recommended way
134 to deal with asynchronous sockets is to avoid interacting with them
135 until they have changed status to "run". This is most easily done
136 from a process sentinel.
138 ** 'make-network-process' and 'open-network-stream' sometimes allowed
139 :service to be an integer string (e.g., :service "993") and sometimes
140 required an integer (e.g., :service 993). This difference has been
141 eliminated, and integer strings work everywhere.
143 ** It is possible to disable attempted recovery on fatal signals.
145 Two new variables support disabling attempts to recover from stack
146 overflow and to avoid automatic auto-save when Emacs is delivered a
147 fatal signal. 'attempt-stack-overflow-recovery', if set to 'nil',
148 will disable attempts to recover from C stack overflows; Emacs will
149 then crash as with any other fatal signal.
150 'attempt-orderly-shutdown-on-fatal-signal', if set to 'nil', will
151 disable attempts to auto-save the session and shut down in an orderly
152 fashion when Emacs receives a fatal signal; instead, Emacs will
153 terminate immediately. Both variables are non-'nil' by default.
154 These variables are for users who would like to avoid the small
155 probability of data corruption due to techniques Emacs uses to recover
159 ** File local and directory local variables are now initialized each
160 time the major mode is set, not just when the file is first visited.
161 These local variables will thus not vanish on setting a major mode.
164 ** A second dir-local file (.dir-locals-2.el) is now accepted.
165 See the variable 'dir-locals-file-2' for more information.
168 ** International domain names (IDNA) are now encoded via the new
169 puny.el library, so that one can visit web sites with non-ASCII URLs.
172 ** The new 'timer-list' command lists all active timers in a buffer,
173 where you can cancel them with the 'c' command.
176 ** The new function 'read-multiple-choice' prompts for multiple-choice
177 questions, with a handy way to display help texts.
180 ** 'switch-to-buffer-preserve-window-point' now defaults to t.
183 * Editing Changes in Emacs 25.2
186 ** New bindings for 'query-replace-map'.
187 'undo', undo the last replacement; bound to 'u'.
188 'undo-all', undo all replacements; bound to 'U'.
191 * Changes in Specialized Modes and Packages in Emacs 25.2
196 *** Messages from CMake are now recognized.
201 *** In wdired, when editing files to contain slash characters,
202 the resulting directories are automatically created. Whether to do
203 this is controlled by the 'wdired-create-parent-directories' variable.
206 *** 'W' is now bound to 'browse-url-of-dired-file', and is useful for
207 viewing HTML files and the like.
211 *** Ediff can be prevented from pausing 1 second after reaching a
212 breakpoint (e.g. with "f" and "o") by customizing the new option
213 'edebug-sit-on-break'.
218 *** A new 's' command for switching to another eww buffer via the minibuffer.
221 *** The 'o' command ('shr-save-contents') has moved to 'O' to avoid collision
222 with the 'o' command from 'image-map'.
225 *** A new command 'C' ('eww-toggle-colors') can be used to toggle
226 whether to use the HTML-specified colors or not. The user can also
227 customize the 'shr-use-colors' variable.
230 *** Images that are being loaded are now marked with gray
231 "placeholder" images of the size specified by the HTML. They are then
232 replaced by the real images asynchronously, which will also now
233 respect width/height HTML specs (unless they specify widths/heights
234 bigger than the current window).
239 *** Images are automatically scaled before displaying based on the
240 'image-scaling-factor' variable (if Emacs supports scaling the images
244 *** Images inserted with 'insert-image' and related functions get a
245 keymap put into the text properties (or overlays) that span the
246 image. This keymap binds keystrokes for manipulating size and
247 rotation, as well as saving the image to a file. These commands are
248 also available in 'image-mode'.
251 *** A new library for creating and manipulating SVG images has been
252 added. See the "SVG Images" section in the lispref manual for
256 *** New setf-able function to access and set image parameters is
257 provided: 'image-property'.
260 ** The default 'Info-default-directory-list' no longer checks some obsolete
261 directory suffixes (gnu, gnu/lib, gnu/lib/emacs, emacs, lib, lib/emacs)
262 when searching for info directories.
265 ** The commands that add ChangeLog entries now prefer a VCS root directory
266 for the ChangeLog file, if none already exists. Customize
267 'change-log-directory-files' to nil for the old behavior.
270 ** Support for non-string values of 'time-stamp-format' has been removed.
275 *** 'message-use-idna' now defaults to t (because Emacs comes with
276 built-in IDNA support now).
279 *** When sending HTML messages with embedded images, and you have
280 exiftool installed, and you rotate images with EXIF data (i.e.,
281 JPEGs), the rotational information will be inserted into the outgoing
282 image in the message. (The original image will not have its
283 orientation affected.)
286 *** The 'message-valid-fqdn-regexp' variable has been removed, since
287 there are now top-level domains added all the time. Message will no
288 longer warn about sending emails to top-level domains it hasn't heard
291 *** 'message-beginning-of-line' (bound to C-a) understands folded headers.
292 In 'visual-line-mode' it will look for the true beginning of a header
293 while in non-'visual-line-mode' it will move the point to the indented
299 *** New connection method "sg", which supports editing files under a
303 *** New connection method "doas" for OpenBSD hosts.
306 ** 'auto-revert-use-notify' is set back to t in 'global-auto-revert-mode'.
311 *** Support for completing attribute values, at-rules, bang-rules, and
312 HTML tags using the 'completion-at-point' command.
315 ** Emacs now supports character name escape sequences in character and
316 string literals. The syntax variants \N{character name} and
317 \N{U+code} are supported.
320 ** Prog mode has some support for multi-mode indentation.
321 This allows better indentation support in modes that support multiple
322 programming languages in the same buffer, like literate programming
323 environments or ANTLR programs with embedded Python code.
325 A major mode can provide indentation context for a sub-mode through
326 the 'prog-indentation-context' variable. To support this, modes that
327 provide indentation should use 'prog-widen' instead of 'widen' and
328 'prog-first-column' instead of a literal zero. See the node
329 "Mode-Specific Indent" in the ELisp manual for more details.
333 *** New variable 'erc-default-port-tls' used to connect to TLS IRC
339 *** The new function 'url-cookie-delete-cookie' can be used to
340 programmatically delete all cookies, or cookies from a specific
344 *** 'url-retrieve-synchronously' now takes an optional timeout parameter.
347 *** The URL package now support HTTPS over proxies supporting CONNECT.
350 *** 'url-user-agent' now defaults to 'default', and the User-Agent
351 string is computed dynamically based on 'url-privacy-level'.
353 ** VC and related modes
356 *** The VC state indicator in the mode line now defaults to more
357 colorful faces to make it more obvious to the user what the state is.
358 See the 'vc-faces' customization group.
361 * New Modes and Packages in Emacs 25.2
363 ** New Elisp data-structure library `radix-tree'.
366 * Incompatible Lisp Changes in Emacs 25.2
369 ** Resizing a frame no longer runs 'window-configuration-change-hook'.
370 Put your function on 'window-size-change-functions' instead.
372 ** 'C-up', 'C-down', 'C-left' and 'C-right' are now defined in term
373 mode to send the same escape sequences that xterm does. This makes
374 things like forward-word in readline work.
377 ** hideshow mode got four key bindings that are analogous to outline
378 mode bindings: 'C-c @ C-a', 'C-c @ C-t', 'C-c @ C-d', and 'C-c @ C-e.'
380 ** The grep/rgrep/lgrep functions will now ask about saving files
381 before running. This is controlled by the 'grep-save-buffers'
385 ** The variable 'text-quoting-style' no longer affects the treatment
386 of curved quotes in format arguments to functions like 'message' and
387 'format-message'. In particular, when this variable's value is
388 'grave', all quotes in formats are output as-is.
390 ** Functions like 'check-declare-file' and 'check-declare-directory'
391 now generate less chatter and more-compact diagnostics. The auxiliary
392 function 'check-declare-errmsg' has been removed.
395 * Lisp Changes in Emacs 25.2
397 ** New var `definition-prefixes' is a hashtable mapping prefixes to the
398 files where corresponding definitions can be found. This can be used
399 to fetch definitions that are not yet loaded, for example for `C-h f'.
401 ** New var syntax-ppss-table to control the syntax-table used in syntax-ppss.
404 ** 'define-derived-mode' can now specify an :after-hook form, which
405 gets evaluated after the new mode's hook has run. This can be used to
406 incorporate configuration changes made in the mode hook into the
409 ** Autoload files can be generated without timestamps,
410 by setting 'autoload-timestamps' to nil.
411 FIXME As an experiment, nil is the current default.
412 If no insurmountable problems before next release, it can stay that way.
414 ** 'ert-with-function-mocked' of 'ert-x package allows mocking of functions
418 ** 'gnutls-boot' now takes a parameter :complete-negotiation that says
419 that negotiation should complete even on non-blocking sockets.
422 ** New functions 'window-pixel-width-before-size-change' and
423 'window-pixel-height-before-size-change' support detecting which
424 window changed size when 'window-size-change-functions' are run.
427 ** New function 'display-buffer-reuse-mode-window' is an action function
428 suitable for use in 'display-buffer-alist'. For example, to avoid creating
429 a new window when opening man pages when there's already one, use
430 (add-to-list 'display-buffer-alist
431 '("\\`\\*Man .*\\*\\'" .
432 (display-buffer-reuse-mode-window
433 (inhibit-same-window . nil)
437 ** There is now a new variable 'flyspell-sort-corrections-function'
438 that allows changing the way corrections are sorted.
441 ** The new command 'fortune-message' has been added, which displays
442 fortunes in the echo area.
445 ** New function 'func-arity' returns information about the argument list
446 of an arbitrary function. This generalizes 'subr-arity' for functions
447 that are not built-in primitives. We recommend using this new
448 function instead of 'subr-arity'.
451 ** 'parse-partial-sexp' state has a new element. Element 10 is
452 non-nil when the last character scanned might be the first character
453 of a two character construct, i.e., a comment delimiter or escaped
454 character. Its value is the syntax of that last character.
457 ** 'parse-partial-sexp''s state, element 9, has now been confirmed as
458 permanent and documented, and may be used by Lisp programs. Its value
459 is a list of currently open parenthesis positions, starting with the
460 outermost parenthesis.
463 ** 'read-color' will now display the color names using the color itself
464 as the background color.
466 ** The function 'redirect-debugging-output' now works on platforms
467 other than GNU/Linux.
470 ** The new function 'string-version-lessp' compares strings by
471 interpreting consecutive runs of numerical characters as numbers, and
472 compares their numerical values. According to this predicate,
473 "foo2.png" is smaller than "foo12.png".
476 ** The new function 'char-from-name' converts a Unicode name string
477 to the corresponding character code.
480 ** New functions 'sxhash-eq' and 'sxhash-eql' return hash codes of a
481 Lisp object suitable for use with 'eq' and 'eql' correspondingly. If
482 two objects are 'eq' ('eql'), then the result of 'sxhash-eq'
483 ('sxhash-eql') on them will be the same.
486 ** Function 'sxhash' has been renamed to 'sxhash-equal' for
487 consistency with the new functions. For compatibility, 'sxhash'
488 remains as an alias to 'sxhash-equal'.
491 ** Time conversion functions that accept a time zone rule argument now
492 allow it to be OFFSET or a list (OFFSET ABBR), where the integer
493 OFFSET is a count of seconds east of Universal Time, and the string
494 ABBR is a time zone abbreviation. The affected functions are
495 'current-time-string', 'current-time-zone', 'decode-time',
496 'format-time-string', and 'set-time-zone-rule'.
499 *** New basic face 'fixed-pitch-serif', for a fixed-width font with serifs.
500 The Info-quoted and tex-verbatim faces now default to inheriting from it.
503 * Changes in Emacs 25.2 on Non-Free Operating Systems
505 ** Intercepting hotkeys on Windows 7 and later now works better.
506 The new keyboard hooking code properly grabs system hotkeys such as
507 Win-* and Alt-TAB, in a way that Emacs can get at them before the
508 system. This makes the 'w32-register-hot-key' functionality work
509 again on all versions of MS-Windows starting with Windows 7. On
510 Windows NT and later you can now register any hotkey combination. (On
511 Windows 9X, the previous limitations, spelled out in the Emacs manual,
514 ** 'convert-standard-filename' no longer mirrors slashes on MS-Windows.
515 Previously, on MS-Windows this function converted slash characters in
516 file names into backslashes. It no longer does that.
519 * Installation Changes in Emacs 25.1
522 ** Building Emacs now requires C99 or later.
525 ** Building Emacs now requires GNU make, version 3.81 or later.
528 ** New configure option --with-cairo.
529 This builds Emacs with Cairo drawing. As a side effect, it provides
530 support for built-in printing, when Emacs was built with GTK+.
531 Cairo drawing is an experimental feature in Emacs, and subject to
532 change in future releases.
535 ** New configure option --with-modules.
536 This enables support for loading dynamic modules; see below.
539 ** By default, Emacs no longer works on IRIX. We expect that Emacs
540 users are not affected by this, as SGI stopped supporting IRIX in
541 December 2013. If you are affected, please send a bug report. You
542 should be able to work around the problem either by porting the Emacs
543 undumping code to GCC under IRIX, or by configuring --with-wide-int,
544 or by sticking with Emacs 24.4.
547 ** The Emacs garbage collector assumes GC_MARK_STACK == GC_MAKE_GCPROS_NOOPS.
548 The GC_MAKE_GCPROS_NOOPS stack-marking variant has been the default
549 since Emacs 24.4, and the other variants were undocumented and were
550 obstacles to maintenance and development. GC_MARK_STACK and its
551 related symbols have been removed from the C internals.
554 ** 'configure' now prefers gnustep-config when configuring GNUstep.
555 If gnustep-config is not available, the old heuristics are used.
558 ** 'configure' now prefers inotify to gfile for file notification,
559 unless gfile is explicitly requested via --with-file-notification='gfile'.
562 ** 'configure' detects the kqueue file notification library on *BSD
563 and Mac OS X machines.
566 ** The configure option '--with-pkg-config-prog' has been removed.
567 Use './configure PKG_CONFIG=/full/name/of/pkg-config' if you need to.
570 ** The configure option '--with-mmdf' has been removed.
571 It was no longer useful, as it relied on libraries that are no longer
572 supported, and its presence led to confusion during configuration.
573 This affects only the 'movemail' utility; Emacs itself can still
574 process MMDF-format files as before.
577 ** The configure option '--enable-silent-rules' is now the default,
578 and silent rules are now quieter. To get the old behavior where
579 'make' chatters a lot, configure with '--disable-silent-rules' or
580 build with 'make V=1'.
583 ** The configure option '--with-gameuser' now allows you to specify a
584 group instead of a user if its argument is prefixed by ':' (a colon).
585 This will cause the game score files in "${localstatedir}/games/emacs"
586 to be owned by that group, and the helper program for updating them to
587 be installed setgid. The option now defaults to the 'games' group.
590 ** The 'grep-changelog' script (and its manual page) are no longer included.
591 It has no particular connection to Emacs and has not changed in years,
592 so if you want to use it, you can always take a copy from an older Emacs.
595 ** Emacs 25 comes with a new set of icons.
596 Various resolutions are available as etc/images/icons/hicolor/*/apps/emacs.png.
597 The old Emacs logo icons are available as 'emacs23.png' in the same location.
600 ** New make target 'check-expensive' to run additional tests.
601 This includes all tests which run via "make check", plus additional
602 tests which take more time to perform.
605 * Startup Changes in Emacs 25.1
608 ** When Emacs is given a file as a command line argument and
609 'initial-buffer-choice' is non-nil, display both the file and
610 'initial-buffer-choice'. When Emacs is given more than one file and
611 'initial-buffer-choice' is non-nil, show 'initial-buffer-choice'
612 and '*Buffer List*'. This makes Emacs convenient to use from the
613 command line when 'initial-buffer-choice' is non-nil.
616 ** The value of 'initial-scratch-message' is now treated as a doc string
617 and can contain escape sequences for command keys, quotes, and the like.
620 ** The default height of GUI frames was enlarged.
621 This is so there's enough space in the initial window to display the
622 optional text about recovering crashes sessions, without losing the
623 splash image display.
626 * Changes in Emacs 25.1
629 ** Xwidgets: a new feature for embedding native widgets inside Emacs buffers.
630 If you have gtk3 and webkitgtk3 installed, and Emacs was built with
631 xwidget support, you can access the embedded webkit browser with 'M-x
632 xwidget-webkit-browse-url'. This opens a new buffer with the embedded
633 browser. The buffer will have a new mode, 'xwidget-webkit-mode'
634 (similar to 'image-mode'), which supports the webkit widget.
637 *** New functions for xwidget-webkit mode 'xwidget-webkit-insert-string',
638 'xwidget-webkit-adjust-size-dispatch', 'xwidget-webkit-back',
639 'xwidget-webkit-browse-url', 'xwidget-webkit-reload',
640 'xwidget-webkit-current-url', 'xwidget-webkit-scroll-backward',
641 'xwidget-webkit-scroll-forward', 'xwidget-webkit-scroll-down',
642 'xwidget-webkit-scroll-up'.
645 ** Emacs can now load shared/dynamic libraries (modules).
646 A dynamic Emacs module is a shared library that provides additional
647 functionality for use in Emacs Lisp programs, just like a package
648 written in Emacs Lisp would. The functions 'load', 'require',
649 'load-file', etc. were extended to load such modules, as they do with
650 Emacs Lisp packages. The new variable 'module-file-suffix' holds the
651 system-dependent value of the file-name extension ('.so' on Posix
652 hosts) of the module files.
654 A module should export a C-callable function named
655 'emacs_module_init', which Emacs will call as part of the call to
656 'load' or 'require' which loads the module. It should also export a
657 symbol named 'plugin_is_GPL_compatible' to indicate that its code is
658 released under the GPL or compatible license; Emacs will refuse to
659 load modules that don't export such a symbol.
661 If a module needs to call Emacs functions, it should do so through the
662 API defined and documented in the header file 'emacs-module.h'. Note
663 that any module that provides Lisp-callable functions will have to use
664 Emacs functions such as 'fset' and 'funcall', in order to register its
665 functions with the Emacs Lisp interpreter.
667 Modules can create 'user-ptr' Lisp objects that embed pointers to C
668 structs defined by the module. This is useful for keeping around
669 complex data structures created by a module, to be passed back to the
670 module's functions. User-ptr objects can also have associated
671 "finalizers" -- functions to be run when the object is GC'ed; this is
672 useful for freeing any resources allocated for the underlying data
673 structure, such as memory, open file descriptors, etc. A new
674 predicate 'user-ptrp' returns non-nil if its argument is a 'user-ptr'
677 Loadable modules in Emacs are an experimental feature, and subject to
678 change in future releases. For that reason, their support is disabled
679 by default, and must be enabled by using the '--with-modules' option
683 ** Network security (TLS/SSL certificate validity and the like) is
684 added via the new Network Security Manager (NSM) and controlled via
685 the 'network-security-level' variable.
688 ** 'C-h l' now also lists the commands that were run.
691 ** 'x-select-enable-clipboard' is renamed 'select-enable-clipboard'
692 and 'x-select-enable-primary' is renamed 'select-enable-primary'.
693 Additionally they both now apply to all systems (OSX, GNUstep, Windows, you
694 name it), with the proviso that on some systems (e.g. Windows)
695 'select-enable-primary' is ineffective since the system doesn't
696 have the equivalent of a primary selection.
699 ** New option 'switch-to-buffer-in-dedicated-window' allows you to
700 customize how 'switch-to-buffer' proceeds interactively when the
701 selected window is strongly dedicated to its buffer.
704 ** The option 'even-window-heights' has been renamed to
705 'even-window-sizes' and now handles window widths as well.
708 ** 'terpri' gets an optional arg ENSURE to conditionally output a newline.
711 ** 'insert-register' now leaves point after the inserted text
712 when called interactively. A prefix argument toggles this behavior.
715 ** The new variable 'term-file-aliases' replaces some files from lisp/term.
716 The function 'tty-run-terminal-initialization' consults this variable
717 when deciding what terminal-specific initialization code to run.
720 ** New variable 'system-configuration-features', listing some of the
721 main features that Emacs was compiled with. This is mainly intended
722 for use in Emacs bug reports.
725 ** A password is now hidden also when typed in batch mode. Another
726 hiding character but the default '.' can be used by let-binding the
727 variable 'read-hide-char'.
730 ** The Emacs pseudo-random number generator can be securely seeded.
731 On systems where Emacs can access the system entropy or some other
732 cryptographically secure random stream, it now uses that when 'random'
733 is called with its argument t. This allows cryptographically strong
734 random values; in particular, the Emacs server now uses this facility
735 to produce its authentication key.
738 ** New input methods: 'tamil-dvorak' and 'programmer-dvorak'.
741 * Editing Changes in Emacs 25.1
744 ** 'M-x' suggests shorthands and ignores obsolete commands for completion.
749 *** Successive single-char deletions are collapsed in the undo-log just like
750 successive char insertions. Which commands invoke this behavior is
751 controlled by the new 'undo-auto-amalgamate' function. See the node
752 "Undo" in the ELisp manual for more details.
755 *** The heuristic used to insert 'undo-boundary' after each command
756 has changed, so that if a command causes changes in more than just the
757 current buffer, Emacs now calls 'undo-boundary' in every buffer
758 affected by the command.
761 ** New command 'comment-line' bound to 'C-x C-;'.
763 ** New and improved facilities for inserting Unicode characters
766 *** Unicode names entered via 'C-x 8 RET' now use substring completion
770 *** 'C-x 8' now has shorthands for several chars, such as U+2010
771 (HYPHEN), U+2011 (NON-BREAKING HYPHEN), and U+2012 (FIGURE DASH). As
772 before, you can type 'C-x 8 C-h' to list shorthands.
775 *** New minor mode 'electric-quote-mode' for using curved quotes as you
776 type. See also the new variable 'text-quoting-style'.
779 ** New minor mode 'global-eldoc-mode' is enabled by default.
782 ** Emacs now uses "bracketed paste mode" on text terminals that support it.
783 Bracketed paste mode causes text terminals to wrap pasted text in special
784 escape sequences that allow Emacs to tell the difference between text
785 you type and text you paste from other applications. Emacs then
786 avoids interpreting each character in the pasted text as it does with
787 keyboard input, which results in a paste experience similar to that
788 under a window system, and significant performance improvements when
789 pasting large amounts of text.
791 Bracketed paste mode is disabled by default, so Emacs automatically
792 enables it at startup if the terminal supports it.
795 ** Emacs now supports the latest version of the UBA.
796 The Emacs implementation of the Unicode Bidirectional Algorithm (UBA)
797 was updated to support all the latest additions and changes introduced
798 in Unicode Standard versions 6.3, 7.0, and the latest Unicode 8.0.
799 This includes full support for directional isolates and the
800 Bidirectional Parentheses Algorithm (BPA) specified by these Unicode
804 ** You can access 'mouse-buffer-menu' ('C-down-mouse-1') using 'C-f10'.
807 ** New buffer-local 'electric-pair-local-mode'.
810 ** New variable 'fast-but-imprecise-scrolling' inhibits
811 fontification during full screen scrolling operations, giving less
812 hesitant operation during auto-repeat of 'C-v', 'M-v' at the cost of
813 possible inaccuracies in the end position.
816 ** New documentation command 'describe-symbol'.
817 Works for functions, variables, faces, etc. It is bound to 'C-h o' by
821 ** New function 'custom-prompt-customize-unsaved-options' checks for
822 unsaved customizations and prompts user to customize (if found). It
823 is intended for adding to 'kill-emacs-query-functions'.
826 ** The old 'C-x w' bindings in 'hi-lock-mode' are officially deprecated
827 in favor of the global 'M-s h' bindings introduced in Emacs 23.1.
828 They'll disappear soon.
831 * Changes in Specialized Modes and Packages in Emacs 25.1
836 *** New command 'checkdoc-package-keywords' checks if the
837 current package keywords are recognized. Set the new option
838 'checkdoc-package-keywords-flag' to non-nil to make
839 'checkdoc-current-buffer' call this function automatically.
842 *** New function 'checkdoc-file' checks for style errors.
843 It's meant for use together with 'compile':
844 emacs -batch --eval "(checkdoc-file \"subr.el\")"
849 *** The desktop format version has been upgraded from 206 to 208.
850 Although Emacs 25.1 can read a version 206 desktop, earlier Emacsen
851 cannot read a version 208 desktop. To upgrade your desktop file, you
852 must explicitly request the upgrade, by 'C-u M-x desktop-save'. You are
853 recommended to do this as soon as you have firmly upgraded to Emacs
854 25.1 (or later). Should you ever need to downgrade your desktop file
855 to version 206, you can do this with 'C-u C-u M-x desktop-save'.
858 *** desktop-restore-in-current-display now defaults to t, not nil.
859 That is, Emacs by default now restores frames into the current display.
862 ** New function 'bookmark-set-no-overwrite' bound to 'C-x r M'.
863 It raises an error if a bookmark of that name already exists,
864 unlike 'bookmark-set' which silently updates an existing bookmark.
869 *** New user options 'mm-html-inhibit-images' and 'mm-html-blocked-images'
870 now control how mm-* functions fetch and display images in an HTML
871 message. Gnus still uses 'gnus-inhibit-images' and 'gnus-blocked-images'
872 for that purpose, i.e., binds mm-html- variables with those gnus-
873 variables, but other packages do not have to bind gnus- variables now.
876 *** 'mm-inline-text-html-with-images' has been removed.
877 Use 'mm-html-inhibit-images' instead. Note that the value is opposite
883 *** 'imap-ssl-program' has been removed, and imap.el uses the internal
884 GnuTLS encryption functions if possible.
889 *** 'json-pretty-print' and 'json-pretty-print-buffer' now maintain
890 the ordering of object keys by default.
893 *** New commands 'json-pretty-print-ordered' and
894 'json-pretty-print-buffer-ordered' pretty prints JSON objects with
895 object keys sorted alphabetically.
897 ** Prettify Symbols mode
900 *** Prettify Symbols mode supports custom composition predicates. By
901 overriding the default 'prettify-symbols-compose-predicate', modes can
902 specify in which contexts a symbol may be displayed as some Unicode
903 character. 'prettify-symbols-default-compose-p' is the default which
904 is suitable for most programming languages such as C or Lisp (but not
908 *** Symbols can be unprettified while point is inside them.
909 New variable 'prettify-symbols-unprettify-at-point' configures this.
911 ** Enhanced xterm support
914 *** The new variable 'xterm-screen-extra-capabilities' for configuring xterm.
915 This variable tells Emacs which advanced capabilities are available in
916 the xterm terminal emulator used to display Emacs text-mode frames.
917 The default is to check each capability, and use it if available.
918 (This variable was introduced in Emacs 24.1, but was not announced in
922 *** Killing text now also sets the CLIPBOARD/PRIMARY selection
923 in the surrounding GUI (using the OSC-52 escape sequence). This only works
924 if your xterm supports it and enables the 'allowWindowOps' options (disabled
925 by default at least in Debian, for security reasons).
927 Similarly, you can yank the CLIPBOARD/PRIMARY selection (using the OSC-52
928 escape sequence) if your xterm has the feature enabled but for that you
929 additionally need to add 'getSelection' to 'xterm-extra-capabilities'.
932 *** 'xterm-mouse-mode' now supports mouse-tracking (if your xterm supports it).
935 ** The way to turn on and off 'save-place' mode has changed.
936 It is no longer sufficient to load the saveplace library and set
937 'save-place' non-nil. Instead, use the two new minor modes:
938 'save-place-mode' turns on saving last place in every file, and
939 'save-place-local-mode' does that only for the file in whose buffer it
940 is invoked. The 'save-place' variable is now an obsolete alias for
941 'save-place-mode', which replaces it, and 'toggle-save-place' is an
942 obsolete alias for the new 'save-place-local-mode' command.
947 *** ERC can now hide message types by network or channel.
948 'erc-hide-list' will hide all messages of the specified type, while
949 'erc-network-hide-list' and 'erc-channel-hide-list' will only hide the
950 specified message types for the respective specified targets.
953 *** Reconnection is now asynchronous.
956 *** Nick completion is now case-insensitive again after inadvertently
957 being made case-sensitive in Emacs 24.2.
962 *** New commands, key binds, and menu items.
964 **** '<' and '>' for navigating previous and next tracks in playlist
966 **** New play/pause command 'mpc-toggle-play' bound to 's'
968 **** 'g' bound to new command 'mpc-seek-current' will navigate current
971 **** New commands 'mpc-toggle-{consume,repeat,single,shuffle}' for
972 toggling playback modes.
975 *** Now supports connecting to a UNIX domain socket.
978 *** Looks at more image file names to use as album art.
979 Case-insensitively tries for .folder.png (freedesktop) and folder.jpg
980 (XP) in addition to cover.jpg.
983 *** Searches in more locations for MPD configuration files.
984 MPD supports the XDG base directory specification since version 0.17.6.
989 *** 'midnight-mode' is now a proper minor mode.
992 *** clean-buffer-*-regexps can now specify buffers via predicate functions.
997 *** New "external" package status.
998 An external package is any installed package that's not built-in and
999 not from 'package-user-dir', which usually means it's from an entry in
1000 'package-directory-list'. They are treated much like built-in
1001 packages, in that they cannot be deleted through the package menu and
1002 are not considered for upgrades.
1004 The effect is that a user can manually place a specific version of a
1005 package inside 'package-directory-list' and the package menu will
1006 always respect that.
1009 *** If a package is available on multiple archives and one has higher
1010 priority (as per 'package-archive-priorities') only that one is
1011 listed. This can be configured with 'package-menu-hide-low-priority'.
1014 *** 'package-menu-toggle-hiding' now toggles the hiding of packages.
1015 This includes the above-mentioned low-priority packages, as well as
1016 available packages whose version is lower than the currently installed
1017 version (which were previously impossible to display).
1018 This allows users to downgrade a package if a lower version is
1022 *** When filtering the package menu, keywords starting with "arc:" or
1023 "status:" represent package archive or status, respectively, instead
1027 *** Most functions which involve downloading information now take an
1028 ASYNC argument. If it is non-nil, package.el performs the download(s)
1032 *** New variable 'package-menu-async' controls whether the
1033 package-menu uses asynchronous downloads.
1036 *** 'package-install-from-buffer' and 'package-install-file' work on directories.
1037 This follows the same rules as installing from a .tar file, except the
1038 -pkg file is optional.
1041 *** Packages which are dependencies of other packages cannot be deleted.
1042 The FORCE argument to 'package-delete' overrides this.
1045 *** New custom variable 'package-selected-packages' tracks packages
1046 which were installed by the user (as opposed to installed as
1047 dependencies). This variable can also be manually customized.
1050 *** New command 'package-install-selected-packages' installs all
1051 packages from 'package-selected-packages' which are currently missing.
1054 *** 'package-install' function now takes a DONT-SELECT argument. If
1055 this function is called interactively or if DONT-SELECT is nil, add the
1056 package being installed to 'package-selected-packages'.
1059 *** New command 'package-autoremove' removes all packages which were
1060 installed strictly as dependencies but are no longer needed.
1065 When you invoke 'shell' interactively, the '*shell*' buffer will now
1066 display in a new window. However, you can customize this behavior via
1067 the 'display-buffer-alist' variable. For example, to get
1068 the old behavior -- '*shell*' buffer displays in current window -- use
1069 (add-to-list 'display-buffer-alist
1070 '("^\\*shell\\*$" . (display-buffer-same-window))).
1074 *** The ':protection' slot option is not obeyed any more.
1076 *** The 'newname' argument to constructors is optional&deprecated.
1077 If you need your objects to be named, do it by inheriting from 'eieio-named'.
1079 *** The <class>-list-p and <class>-child-p functions are declared obsolete.
1081 *** The <class> variables are declared obsolete.
1083 *** The <initarg> variables are declared obsolete.
1085 *** defgeneric and defmethod are declared obsolete.
1086 Use the equivalent facilities from cl-generic.el instead.
1088 *** 'constructor' is now an obsolete alias for 'make-instance'.
1090 *** 'pcase' accepts a new UPattern 'eieio'.
1095 *** New command 'ido-bury-buffer-at-head' bound to 'C-S-b'.
1096 Bury the buffer at the head of 'ido-matches', analogous to how 'C-k'
1097 kills the buffer at head.
1100 *** A prefix argument to 'ido-restrict-to-matches' will reverse its
1101 meaning, and the list is restricted to those elements that do not
1102 match the current input.
1107 *** You can use <UP> and <DOWN> arrow keys to move through history by lines.
1108 The new commands 'next-line-or-history-element' and
1109 'previous-line-or-history-element', bound to <UP> and <DOWN> in the
1110 minibuffer, allow by-line movement through minibuffer history,
1111 similarly to an ordinary buffer. Only when point moves over
1112 the bottom/top of the minibuffer it goes to the next/previous history
1113 element. 'M-p' and 'M-n' still move directly to previous/next history
1116 ** Search and Replace
1119 *** 'isearch' and 'query-replace' can now perform character folding in matches.
1120 This is analogous to case folding, but instead of disregarding case
1121 variants, it disregards wider classes of distinctions between similar
1122 characters. (Case folding is a special case of character folding.)
1123 This means many characters in the search string will match entire
1124 groups of characters instead of just themselves.
1126 For instance, the ASCII double quote character " will match all
1127 variants of double quotes, and the letter 'a' will match all of its
1128 accented cousins, even those composed of multiple characters, as well
1129 as many other symbols like U+249C (PARENTHESIZED LATIN SMALL LETTER
1132 Character folding is enabled by customizing 'search-default-mode' to
1133 the value 'char-fold-to-regexp'. You can also toggle character
1134 folding in the middle of a search by typing 'M-s ''.
1136 'query-replace' honors character folding if the new variable
1137 'replace-char-fold' is customized to a non-nil value.
1140 *** New user option 'search-default-mode'.
1141 This option specifies the default mode for Isearch. The default
1142 value, nil specifies that Isearch does literal searches (however,
1143 'case-fold-search' and 'isearch-lax-whitespace' may still be applied,
1144 as in previous Emacs versions).
1147 *** New function 'char-fold-to-regexp' can be used
1148 by searching commands to produce a regexp matching anything that
1149 char-folds into STRING.
1152 *** The new 'M-s M-w' key binding uses eww to search the web for the
1153 text in the region. The search engine to use for this is specified by
1154 the customizable variable 'eww-search-prefix'.
1157 *** 'query-replace' history is enhanced.
1158 When 'query-replace' reads the FROM string from the minibuffer, typing
1159 'M-p' will now show previous replacements as "FROM SEP TO", where FROM
1160 and TO are the original text and its replacement, and SEP is an arrow
1161 string defined by the new variable 'query-replace-from-to-separator'.
1162 To select a prior replacement, type 'M-p' until the desired
1163 replacement appears in the minibuffer, and then exit the minibuffer by
1168 *** If 'quick-calc' is called with a prefix argument, insert the
1169 result of the calculation into the current buffer.
1172 ** In Edebug, you can now set the initial mode with 'C-x C-a C-m'.
1173 With this you can tell Edebug not to stop at the start of the first
1174 instrumented function.
1179 *** New minor mode 'global-eldoc-mode'.
1180 It is turned on by default, and affects '*scratch*' and other buffers
1181 whose major mode supports Emacs Lisp.
1184 *** 'eldoc-documentation-function' now defaults to 'ignore'.
1187 *** 'describe-char-eldoc' displays information about character at point,
1188 and can be used as a default value of 'eldoc-documentation-function'. It is
1189 useful when, for example, one needs to distinguish various spaces - e.g.,
1190 U+00A0 (NO-BREAK SPACE), U+2002 (EN SPACE), and U+2009 (THIN SPACE) - while
1191 using mono-spaced font.
1196 *** HTML can now be rendered using variable-width fonts.
1199 *** A new command 'F' ('eww-toggle-fonts') can be used to toggle
1200 whether to use variable-pitch fonts or not. The user can also
1201 customize the 'shr-use-fonts' variable.
1204 *** A new command 'R' ('eww-readable') will try do identify the main
1205 textual parts of a web page and display only that, leaving menus and
1206 the like off the page.
1209 *** A new command 'D' ('eww-toggle-paragraph-direction') allows you to
1210 toggle the paragraph direction between left-to-right and right-to-left.
1213 *** You can now use several eww buffers in parallel by renaming eww
1214 buffers you want to keep separate.
1217 *** Partial state of the eww buffers (the URIs and the titles of the
1218 pages visited) is now preserved in the desktop file.
1221 *** 'eww-after-render-hook' is now called after eww has rendered
1222 the data in the buffer.
1225 *** The 'eww-reload' command now takes a prefix to not reload via
1226 the net, but just use the local copy of the HTML.
1229 *** The DOM shr and eww uses has been changed to the general Emacs
1230 xml.el/libxml2 DOM, and a new package dom.el has been added to
1231 interact with this DOM. See the Emacs Lisp manual for interface
1235 *** 'mailcap-mime-data' is now consulted when displaying PDF files.
1238 *** The new 'S' command will list all eww buffers, and allow managing
1242 *** https pages with valid certificates have headers marked in green, while
1243 invalid certificates are marked in red.
1248 *** text/html messages that contain inline image parts will be
1249 transformed into multipart/related messages before sending.
1252 ** In Show Paren Mode, a parenthesis can be highlighted when point
1253 stands inside it, and certain parens can be highlighted when point is
1254 at BOL or EOL, or in whitespace there. To enable these, customize,
1255 respectively, 'show-paren-when-point-inside-paren' or
1256 'show-paren-when-point-in-periphery'.
1259 ** If gpg2 exists on the system, it is now used as the default value
1260 of 'epg-gpg-program' (instead of gpg).
1265 *** Strings after ':documentation' are highlighted as docstrings.
1266 This enhances Lisp mode fontification to handle documentation of the
1267 form '(:documentation "the doc string")' used in Common Lisp code for
1268 CLOS class and slot documentation.
1270 ** Rectangle editing
1273 *** Rectangle Mark mode can have corners past EOL or in the middle of a TAB.
1276 *** 'C-x C-x' in 'rectangle-mark-mode' now cycles through the four corners.
1277 *** 'string-rectangle' provides on-the-fly preview of the result.
1280 ** New font-lock functions 'font-lock-ensure' and 'font-lock-flush'.
1281 These should be used in preference to 'font-lock-fontify-buffer' when
1285 ** Macro 'minibuffer-with-setup-hook' can optionally append a function
1286 to 'minibuffer-setup-hook'.
1288 If the first argument of the macro is of the form '(:append FUN)',
1289 then FUN will be appended to 'minibuffer-setup-hook', instead of
1294 *** New functions 'cl-fresh-line', 'cl-digit-char-p', and 'cl-parse-integer'.
1297 *** 'pcase' accepts the new UPattern 'cl-struct'.
1299 ** Calendar and diary
1302 *** The default 'diary-file' is now located in "~/.emacs.d".
1305 *** New commands to insert diary entries with Chinese dates:
1306 'diary-chinese-insert-anniversary-entry' 'diary-chinese-insert-entry'
1307 'diary-chinese-insert-monthly-entry', 'diary-chinese-insert-yearly-entry'.
1310 *** The calendar can now list and mark diary entries with Chinese dates.
1311 See 'diary-chinese-list-entries' and 'diary-chinese-mark-entries'.
1314 *** The option 'calendar-mode-line-format' can now be nil,
1315 which means to do nothing special with the mode line in calendars.
1318 *** New option 'calendar-weekend-days'.
1319 The option customizes which day headers receive the
1320 'calendar-weekend-header' face.
1323 *** New optional args N and STRING for 'holiday-greek-orthodox-easter'.
1326 *** Many items obsolete since at least version 23.1 have been removed.
1327 The majority were function/variable/face aliases, too numerous to list here.
1330 **** Functions 'calendar-one-frame-setup', 'calendar-only-one-frame-setup',
1331 'calendar-two-frame-setup', 'european-calendar', 'american-calendar'.
1333 **** Hooks 'cal-menu-load-hook', 'cal-x-load-hook'.
1335 **** Macro 'calendar-for-loop'.
1337 **** Variables 'european-calendar-style', 'diary-face', 'hebrew-holidays-{1,4}'.
1339 **** The nil and list forms of 'diary-display-function'.
1342 ** New ERT function 'ert-summarize-tests-batch-and-exit'.
1343 If the output of ERT tests in batch mode execution can be saved to a
1344 log file, then it can be passed as an argument to the above function
1345 to produce a neat summary.
1348 ** New js.el option 'js-indent-first-init'.
1353 ** Info mode now displays symbol names in fixed-pitch font.
1354 If you want to get the old behavior back, customize the 'Info-quoted'
1355 face to use the same definitions as the default face.
1358 *** 'Info-fontify-maximum-menu-size' can be t for no limit.
1361 *** 'info-display-manual' can now be given a prefix argument which (any
1362 non-nil value) directs the command to limit the completion
1363 alternatives to currently visited manuals.
1366 ** ntlm.el has support for NTLM2.
1371 *** The Rmail commands 'd', 'C-d' and 'u' take optional repeat counts
1372 to delete or undelete multiple messages.
1375 *** Rmail can now render HTML mail messages if your Emacs was built with
1376 libxml2 or if you have the Lynx browser installed. By default, Rmail
1377 will display the HTML version of a mail message that has both HTML and
1378 plain text parts, if display of HTML email is possible; customize the
1379 'rmail-mime-prefer-html' option to nil if you don't want that.
1382 *** In the commands that make summaries by subject, recipients, or senders,
1383 you can no longer use commas to separate regular expressions.
1386 ** SES now supports local printer functions; see 'ses-define-local-printer'.
1388 ** Shell-script Mode
1390 *** In sh-mode you can now use 'sh-shell' as a file-local variable to
1391 specify the type of shell in use (bash, csh, etc).
1394 *** New value 'always' for 'sh-indent-after-continuation'.
1395 This provides old-style ("dumb") indentation of continued lines.
1396 See the doc string of 'sh-indent-after-continuation' for details.
1400 *** Fatal TLS errors are now silent by default.
1403 *** If Emacs isn't built with TLS support, an external TLS-capable
1404 program is used instead. This program used to be run in --insecure
1405 mode by default, but has now changed to be secure instead, and will
1406 fail if you try to connect to non-verifiable hosts. This is
1407 controlled by the 'tls-program' variable.
1412 *** The URL package accepts now the protocols "ssh", "scp" and "rsync".
1413 When 'url-handler-mode' is enabled, file operations for these
1414 protocols as well as for "telnet" and "ftp" are passed to Tramp.
1417 *** The URL package allows customizing the 'url-user-agent' string.
1418 The new 'url-user-agent' variable can be customized to be a string or
1422 *** The new interface variable 'url-request-noninteractive' can be used
1423 to specify that we're running in a noninteractive context, and that
1424 we should not be queried about things like TLS certificate validity.
1427 *** 'url-mime-accept-string' can now be used as in "interface"
1428 variable, meaning you can bind it around an 'url-retrieve' call.
1431 *** If URL is used with a https connection, the first callback argument
1432 PLIST will contain a :peer element that has the output of
1433 'gnutls-peer-status' (if Emacs is built with GnuTLS support).
1438 *** New connection method "afp", which allows you to access Mac OS X
1439 volumes via the Apple Filing Protocol.
1442 *** New connection method "nc", which allows you to access dumb
1446 *** Method-specific parameters can be overwritten now with variable
1447 'tramp-connection-properties'.
1450 *** Handler for 'file-notify-valid-p' for remote machines that support
1451 filesystem notifications.
1456 *** New user variable 'sql-default-directory' enables remote
1457 connections using Tramp.
1460 *** New command 'sql-send-line-and-next'.
1461 This command, bound to 'C-c C-n' by default, sends the current line to
1462 the SQL process and advances to the next line, skipping whitespace and
1466 *** Added support for Vertica SQL.
1468 ** VC and related modes
1471 *** Basic push support, via 'vc-push', bound to 'C-x v P'.
1472 Implemented for Bzr, Git, Hg. As part of this change, the pre-existing
1473 (undocumented) command 'vc-hg-push' now behaves slightly differently.
1476 *** The new command 'vc-region-history' shows the log+diff of the active region.
1479 *** You can refresh the VC state of a file buffer with 'M-x vc-refresh-state'.
1480 This command is useful when you perform version control commands
1481 outside Emacs (e.g., from the shell prompt), or if you switch the VC
1482 back-end for the buffer's file, or remove it from version control.
1485 *** New option 'vc-annotate-background-mode' controls whether
1486 the color range from 'vc-annotate-color-map' is applied to the
1487 background or to the foreground.
1490 *** New options for customizing encoding of Git commit log messages.
1491 The new user options 'vc-git-commits-coding-system' and
1492 'vc-git-log-output-coding-system' specify the encoding of log messages
1493 sent to Git when committing, and the decoding of log messages read
1494 from Git history commands. These options default to UTF-8; if
1495 customized, they should be consistent with the Git config variables
1496 i18n.commitEncoding and i18n.logOutputEncoding.
1497 ('vc-git-commits-coding-system' existed previously, but was a
1498 variable, not a user option.)
1501 *** 'compare-windows' now compares text with the most recently selected window
1502 instead of the next window. If you want the previous behavior of
1503 comparing with the next window, customize the new option
1504 'compare-windows-get-window-function' to the value
1505 'compare-windows-get-next-window'.
1508 *** Two new faces 'compare-windows-removed' and 'compare-windows-added'
1509 replace the face 'compare-windows', which is now an obsolete alias for
1510 'compare-windows-added'.
1513 *** The VC state indicator in the mode line now has different faces
1514 corresponding to each of the possible states. See the 'vc-faces'
1515 customization group.
1518 *** 'log-edit-insert-changelog' converts "(tiny change)" to
1519 "Copyright-paperwork-exempt: yes". Set 'log-edit-rewrite-tiny-change'
1520 nil to disable this.
1523 *** vc-mcvs.el has been removed.
1526 ** VHDL mode now supports VHDL'08.
1531 *** Decimal display mode uses "," groups, so it's more
1532 fitting for use in money calculations
1535 *** Factorial works with non-integer inputs.
1540 *** Hide-IfDef mode now support full C/C++ expressions in macros,
1541 macro argument expansion, interactive macro evaluation and automatic
1542 scanning of #define'd symbols.
1545 *** New command 'hif-evaluate-macro', bound to 'C-c @ e', displays the
1546 result of evaluating a macro.
1549 *** New command 'hif-clear-all-ifdef-define', bound to 'C-c @ C', clears
1550 all defined symbols in 'hide-ifdef-env'.
1553 *** New custom variable 'hide-ifdef-header-regexp' to define C/C++ header
1554 file name patterns. Defaults to files whose extension is one of '.h',
1555 '.hh', '.hpp', '.hxx', or '.h++', matched case-insensitively.
1558 *** New custom variable 'hide-ifdef-expand-reinclusion-protection' to prevent
1559 reinclusion protected (a.k.a. "idempotent") header files from being hidden.
1560 (This could happen when an idempotent header file is visited again,
1561 when its guard symbol is already defined.) Defaults to t.
1564 *** New custom variable 'hide-ifdef-exclude-define-regexp' to define symbol
1565 name patterns (e.g. all "FOR_DOXYGEN_ONLY_*") to be ignored when
1566 looking for macro definitions. By default, no symbols are ignored.
1571 *** New custom variable 'tex-print-file-extension' to help users who
1572 use PDF instead of DVI.
1575 *** TeX mode now supports Prettify Symbols mode. When enabling
1576 'prettify-symbols-mode' in a tex-mode buffer, \alpha ... \omega, and
1577 many other math macros are displayed using unicode characters.
1580 ** New 'big-indent' style in 'whitespace-mode' highlights deep indentation.
1581 By default, 32 consecutive spaces or four consecutive TABs are
1582 considered to be too deep, but the new variable
1583 'whitespace-big-indent-regexp' can be customized to change that.
1586 ** New options in 'tildify-mode'.
1587 New options 'tildify-space-string', 'tildify-pattern', and
1588 'tildify-foreach-region-function' variables make
1589 'tildify-string-alist', 'tildify-pattern-alist', and
1590 'tildify-ignored-environments-alist' variables (as well as a few
1591 helper functions) obsolete.
1594 ** New package Xref replaces Etags's front-end and UI.
1596 The new package Xref provides a generic framework and new commands to
1597 find and move to definitions of functions, macros, data structures
1598 etc., as well as go back to the location where you were before moving
1599 to a definition. It supersedes and obsoletes many Etags commands,
1600 while still using the etags.el code that reads the TAGS tables as one
1603 The command 'xref-find-definitions' replaces 'find-tag' and provides
1604 an interface to pick one definition among several.
1605 'tags-loop-continue' is now unbound. 'xref-pop-marker-stack' replaces
1606 'pop-tag-mark', but has a keybinding ('M-,') different from the one
1607 'pop-tag-mark' used.
1609 'xref-find-definitions-other-window' replaces 'find-tag-other-window'.
1610 'xref-find-definitions-other-frame' replaces 'find-tag-other-frame'.
1611 'xref-find-apropos' replaces 'find-tag-regexp'.
1613 As a result of this, the following commands are now obsolete:
1614 'find-tag-other-window', 'find-tag-other-frame', 'find-tag-regexp',
1617 'tags-loop-continue' is not obsolete because it's still useful in
1618 'tags-search' and 'tags-query-replace', for which there are no direct
1622 *** Variants of 'tags-search' and 'tags-query-replace' in Dired were also
1623 replaced by xref-style commands, see the "Dired" section below.
1628 'find-tag-marker-ring-length' is now an obsolete alias for
1629 'xref-marker-ring-length'. 'find-tag-marker-ring' is now an obsolete
1630 alias for a private variable. 'xref-push-marker-stack' and
1631 'xref-pop-marker-stack' should be used instead to manipulate the stack
1632 of searches for definitions.
1635 *** 'xref-find-definitions' and 'describe-function' now display
1636 information about mode local overrides (defined by cedet/mode-local.el
1637 'define-overloadable-function' 'define-mode-local-overrides').
1639 The framework's Lisp API is still experimental and can change in major,
1640 backward-incompatible ways.
1643 ** New package Project
1645 The new package Project provides generic infrastructure for dealing
1646 with projects. The main commands included in it are
1647 'project-find-file' and 'project-find-regexp'.
1649 The Lisp API of this package is still experimental.
1652 EUDC's LDAP backend has been improved.
1655 *** EUDC supports LDAP-over-SSL URLs (ldaps://).
1658 *** EUDC passes LDAP passwords through a pipe to the ldapsearch
1659 subprocess instead of on the command line.
1662 *** EUDC handles LDAP wildcards automatically so the user shouldn't
1663 need to configure this manually anymore.
1666 *** The LDAP configuration section of EUDC's manual has been
1669 There have also been customization changes.
1672 *** New custom variable 'eudc-server-hotlist' to allow specifying
1673 multiple EUDC servers in init file.
1676 *** Custom variable 'eudc-inline-query-format' defaults to completing
1677 on email and firstname instead of surname.
1680 *** Custom variable 'eudc-expansion-overwrites-query' defaults to nil
1681 to avoid interfering with the kill ring.
1684 *** Custom variable 'eudc-inline-expansion-format' defaults to
1685 "Firstname Surname <mail-address>".
1688 *** Custom variable 'eudc-options-file' defaults to
1689 "~/.emacs.d/eudc-options".
1692 *** New custom variable 'ldap-ldapsearch-password-prompt-regexp' to
1693 allow overriding the regular expression that recognizes the ldapsearch
1694 command line's password prompt.
1697 EUDC's BBDB backend now supports BBDB 3.
1700 EUDC's PH backend (eudcb-ph.el) is obsolete.
1705 *** The new built-in command 'clear' can scroll window contents out of sight.
1706 If provided with an optional non-nil argument, the scrollback contents
1710 *** New buffer syntax '#<buffer-name>', which is equivalent to
1711 '#<buffer buffer-name>'. This shorthand makes interacting with
1712 buffers from eshell more convenient. Custom variable
1713 'eshell-buffer-shorthand', which has been broken for a while, has been
1717 *** By default, eshell "visual" program buffers (created by
1718 'eshell-visual-commands' and similar custom vars) are no longer killed
1719 when their processes die. This fixes issues with short-lived commands
1720 and makes visual programs more useful in general. For example, if
1721 "git log" is a visual command, it will always show the visual command
1722 buffer, even if the "git log" process dies. For the old behavior,
1723 make the new option 'eshell-destroy-buffer-when-process-dies' non-nil.
1728 *** Support for the Google Chrome web browser.
1731 *** Support for the Conkeror web browser.
1734 *** Support for several ancient browsers is now officially obsolete.
1737 ** 'tar-mode': new 'tar-new-entry' command, allowing for new members to
1738 be added to the archive.
1743 *** Dired buffers are also auto-reverted via file notifications, if
1744 Emacs is compiled with file notification support.
1747 *** 'auto-revert-use-notify' is set to nil in 'global-auto-revert-mode'.
1748 See <http://debbugs.gnu.org/22814>.
1750 ** File Notifications
1753 *** The kqueue library is integrated for *BSD and Mac OS X machines.
1756 *** The new event 'stopped' signals, that a file notification watch is
1757 not active any longer.
1760 *** The new function 'file-notify-valid-p' checks, whether a file
1761 notification descriptor still corresponds to an activate watch.
1766 *** The command 'dired-do-compress', bound to 'Z', now can compress
1767 directories and decompress zip files.
1770 *** New command 'dired-do-compress-to', bound to 'c', can be used to
1771 compress many marked files into a single named archive. The
1772 compression command is determined from the new
1773 'dired-compress-files-alist' variable.
1776 *** New user interface for the 'A' and 'Q' commands.
1777 These keys, now bound to 'dired-do-find-regexp' and
1778 'dired-do-find-regexp-and-replace', work similarly to 'xref-find-apropos'
1779 and 'xref-query-replace-in-results': they present the matches
1780 in the '*xref*' buffer and let you move through the matches. No need
1781 to use 'tags-loop-continue' to resume the search or replace loop. The
1782 previous commands, 'dired-do-search' and
1783 'dired-do-query-replace-regexp', are still available, but not bound to
1784 keys; rebind 'A' and 'Q' to invoke them if you want the old behavior
1785 back. We intend to obsolete the old commands in a future release.
1787 ** Tabulated List Mode
1790 *** It is now safe for a mode that derives 'tabulated-list-mode' to not
1791 call 'tabulated-list-init-header', in which case it will have no
1795 *** 'tabulated-list-print' takes a second optional argument, UPDATE,
1796 which specifies an alternative printing method which is faster when
1797 few or no entries have changed.
1799 ** Obsolete packages
1805 *** landmark.el (moved to elpa.gnu.org)
1808 * New Modes and Packages in Emacs 25.1
1811 ** pinentry.el allows GnuPG passphrase to be prompted through the
1812 minibuffer instead of a graphical dialog, depending on whether the gpg
1813 command is called from Emacs (i.e., INSIDE_EMACS environment variable
1814 is set). This feature requires newer versions of GnuPG (2.1.5 or
1815 later) and Pinentry (0.9.5 or later). To use this feature, add
1816 "allow-emacs-pinentry" to "~/.gnupg/gpg-agent.conf" and reload the
1817 configuration with "gpgconf --reload gpg-agent".
1820 ** cl-generic.el provides CLOS-style multiple-dispatch generic functions.
1821 The main entry points are 'cl-defgeneric' and 'cl-defmethod'. See the
1822 node "Generic Functions" in the Emacs Lisp manual for more details.
1825 ** 'scss-mode' (a minor variant of 'css-mode') is a major mode for editing
1826 SCSS (Sassy CSS) files.
1829 ** 'let-alist' is a new macro (and a package) that allows one to easily
1830 let-bind the values stored in an alist.
1833 ** 'tildify-mode' allows automatic insertion of hard spaces as one
1834 types the text. Breaking line after a single-character words is
1835 forbidden by Czech and Polish typography (and may be discouraged in
1836 other languages), so 'auto-tildify-mode' makes it easier to create
1837 a typographically-correct documents.
1840 ** The 'seq' library adds sequence manipulation functions and macros
1841 that complement basic functions provided by subr.el. All functions
1842 are prefixed with 'seq-' and work on lists, strings and vectors.
1843 'pcase' accepts a new Upattern 'seq'.
1846 ** The 'map' library provides map-manipulation functions that work on
1847 alists, hash-table and arrays. All functions are prefixed with
1848 'map-'. 'pcase' accepts a new UPattern 'map'.
1851 ** The 'thunk' library provides functions and macros to control the
1852 evaluation of forms.
1855 ** 'js-jsx-mode' (a minor variant of 'js-mode') provides indentation
1856 support for JSX, an XML-like syntax extension to ECMAScript.
1859 * Incompatible Lisp Changes in Emacs 25.1
1862 ** 'setq' and 'setf' must now be called with an even number of
1863 arguments. The earlier behavior of silently supplying a nil to the
1864 last variable when there was an odd number of arguments has been
1868 ** 'syntax-begin-function' is declared obsolete.
1869 Removed 'font-lock-beginning-of-syntax-function' and the SYNTAX-BEGIN
1870 slot in 'font-lock-defaults'.
1873 ** The new implementation of Subword mode affects word movement everywhere.
1874 When Subword mode is turned on, 'forward-word', 'backward-word', and
1875 everything that uses them will move by sub-words, effectively
1876 overriding the buffer's syntax table. Lisp programs that shouldn't be
1877 affected by Subword mode should call the new functions
1878 'forward-word-strictly' and 'backward-word-strictly' instead.
1881 ** 'package-initialize' now sets 'package-enable-at-startup' to nil if
1882 called during startup. Users who call this function in their init
1883 file and still expect it to be run after startup should set
1884 'package-enable-at-startup' to t after the call to
1885 'package-initialize'.
1888 ** ':global' minor mode use 'setq-default' rather than 'setq'.
1889 This means that you can't use 'make-local-variable' and expect them to
1890 "magically" become buffer-local.
1893 ** 'track-mouse' no longer freezes the shape of the mouse pointer.
1894 The 'track-mouse' form no longer refrains from changing the shape of
1895 the mouse pointer for the entire time the body of that form is
1896 executed. Lisp programs that use 'track-mouse' for dragging across
1897 large portions of the Emacs display, and want to avoid changes in the
1898 pointer shape during dragging, should bind the variable 'track-mouse'
1899 to the special value 'dragging' in the body of the form.
1902 ** The optional PREDICATE argument of 'lisp-complete-symbol' no longer
1903 has any effect. (This change was made in Emacs 24.4 but was not
1904 advertised at the time.)
1907 ** 'indirect-function' does not signal 'void-function' any more.
1908 This is mostly a bug-fix, since this change was missed back in 24.4 when
1909 'symbol-function' was changed not to signal 'void-function' any more.
1912 *** As a consequence, the second arg of 'indirect-function' is now obsolete.
1915 ** 'M-x shell' and 'M-x compile' no longer set the EMACS environment variable.
1916 This avoids clashing when other programs use the variable for other purposes.
1917 Although 'M-x term' still sets EMACS for compatibility with Bash 4.3
1918 and earlier, this is deprecated and will be phased out when Bash 4.4
1919 or later takes over. Use the INSIDE_EMACS environment variable instead.
1922 ** 'save-excursion' does not save&restore the mark any more.
1923 Use 'save-mark-and-excursion' if you want the old behavior.
1926 ** 'read-buffer' and 'read-buffer-function' can now be called with a 4th
1927 argument (PREDICATE).
1930 ** 'completion-table-dynamic' by default stays in the minibuffer.
1931 The minibuffer will be the current buffer when the function is called.
1932 If you want the old behavior of calling the function in the buffer
1933 from which the minibuffer was entered, use the new argument
1934 SWITCH-BUFFER to 'completion-table-dynamic'.
1937 ** window-configurations no longer record the buffers' marks.
1940 ** 'inhibit-modification-hooks' now also inhibits lock-file checks, as
1941 well as active region handling.
1944 ** 'deactivate-mark' is now buffer-local.
1947 ** 'cl-the' now asserts that its argument is of the given type.
1950 ** 'process-running-child-p' may now return a numeric process
1951 group ID instead of t.
1954 ** Mouse click events on mode line or header line no longer include
1955 any reference to a buffer position. The 6th member of the mouse
1956 position list returned for such events is now nil.
1959 ** Menu items in keymaps do not support the "key shortcut cache" any more.
1960 These slots used to hold key-shortcut data, but have been obsolete since
1964 ** Emacs no longer downcases the first letter of a system diagnostic
1965 when signaling a file error. For example, it now reports "Permission
1966 denied" instead of "permission denied". The old behavior was problematic
1967 in languages like German where downcasing rules depend on grammar.
1970 ** New variable 'text-quoting-style' to control how Emacs translates quotes.
1971 Set it to 'curve' for curved single quotes, to 'straight' for straight
1972 apostrophes, and to 'grave' for grave accent and apostrophe. The
1973 default value nil acts like 'curve' if curved single quotes are
1974 displayable, and like 'grave' otherwise. The new variable affects
1975 display of diagnostics and help, but not of info. As the variable is
1976 not intended for casual use, it is not a user option.
1979 ** Message-issuing functions like 'message' and 'error' now translate
1980 various sorts of single quotes in their format strings according to
1981 the value of 'text-quoting-style' (see above). This translation
1982 cannot be disabled. To get the old behavior, use 'format', which is
1983 not affected by 'text-quoting-style', e.g., (message "%s" (format
1987 ** 'substitute-command-keys' now replaces quotes.
1988 That is, it converts documentation strings' quoting style as per the
1989 value of 'text-quoting-style'. Doc strings in source code can use
1990 either curved single quotes or grave accents and apostrophes. As
1991 before, characters preceded by \= are output as-is.
1994 ** The character classes [:alpha:] and [:alnum:] in regular expressions
1995 now match multibyte characters using Unicode character properties.
1996 If you want the old behavior where they matched any character with
1997 word syntax, use '\sw' instead.
2000 ** The character classes [:graph:] and [:print:] in regular expressions
2001 no longer match every multibyte character. Instead, Emacs now
2002 consults the Unicode character properties to determine which
2003 characters are graphic or printable. In particular, surrogates and
2004 unassigned codepoints are now rejected. If you want the old behavior,
2005 use [:multibyte:] instead.
2008 ** The 'diff' command uses the unified format now. To restore the old
2009 behavior, set 'diff-switches' to '-c'.
2012 ** 'grep-template' and 'grep-find-template' values don't include the
2013 --color argument anymore. It's added at the <C> place holder position
2014 dynamically. Any third-party code that changes these templates should
2015 be updated accordingly.
2018 ** '(/ N)' is now equivalent to '(/ 1 N)' rather than to '(/ N 1)'.
2019 The new behavior is compatible with Common Lisp and with XEmacs.
2020 This change does not affect Lisp code intended to be portable to
2021 Emacs 24.2 and earlier, which did not support unary '/'.
2024 ** The 'default-directory' value doesn't have to end slash. To make
2025 that happen, 'unhandled-file-name-directory' now defaults to calling
2026 'file-name-as-directory'.
2029 * Lisp Changes in Emacs 25.1
2033 *** New UPatterns 'quote', 'app'.
2035 *** New UPatterns can be defined with 'pcase-defmacro'.
2037 *** New vector QPattern.
2040 ** 'syntax-propertize' is now automatically called on-demand during forward
2041 parsing functions like 'forward-sexp'.
2044 ** New hooks 'prefix-command-echo-keystrokes-functions' and
2045 'prefix-command-preserve-state-hook' allow the definition of prefix
2046 commands other than the predefined 'C-u'.
2049 ** New functions 'filepos-to-bufferpos' and 'bufferpos-to-filepos'.
2050 These allow conversion between buffer positions and the corresponding
2051 file byte offsets, given the file's encoding.
2054 ** The default value of 'load-read-function' is now 'read'.
2055 Previously, the default value of nil implied using 'read'.
2058 ** New hook 'pre-redisplay-functions'.
2059 It is a bit easier to use than 'pre-redisplay-function'.
2062 ** The second arg of 'looking-back' should always be provided explicitly.
2063 Previously, it was an optional argument, now it's mandatory.
2066 ** Text properties 'intangible', 'point-entered', and 'point-left' are obsolete.
2067 Replaced by properties 'cursor-intangible' and 'cursor-sensor-functions',
2068 implemented by the new 'cursor-intangible-mode' and
2069 'cursor-sensor-mode' minor modes.
2072 ** 'inhibit-point-motion-hooks' now defaults to t and is obsolete.
2073 Use the new minor modes 'cursor-intangible-mode' and
2074 'cursor-sensor-mode' instead.
2077 ** New process type 'pipe', which can be used in combination with the
2078 ':stderr' keyword of 'make-process' to handle standard error output
2082 ** New function 'make-process' provides an alternative interface to
2083 'start-process'. It allows programs to set process parameters such as
2084 process filter, sentinel, etc., through keyword arguments (similar to
2085 'make-network-process').
2088 ** Subprocesses are automatically told about changes in window dimensions.
2089 The new option 'window-adjust-process-window-size-function' controls
2090 how subprocesses are told to adapt their logical window sizes to
2091 changes in the Emacs window configuration. Its default value calls
2092 'set-process-window-size' with the smallest dimensions of all the
2093 windows that display the subprocess's buffer.
2096 ** A new function 'directory-files-recursively' returns all matching
2097 files (recursively) under a directory.
2100 ** New variable 'inhibit-message', when bound to non-nil, inhibits
2101 'message' and related functions from displaying messages in the echo
2102 area. The output is still logged to the '*Messages*' buffer.
2105 ** A new text property 'inhibit-read-only' can be used in read-only
2106 buffers to allow certain parts of the text to be writable.
2109 ** A new variable 'comment-end-can-be-escaped' is useful in languages
2110 such as C and C++ where line comments with escaped newlines are
2111 continued to the next line.
2114 ** New macro 'define-advice'.
2117 ** Emacs Lisp now supports generators.
2118 See the "Generators" section of the ELisp manual for the details.
2121 ** New finalizer facility for running code when objects become unreachable.
2122 See the "Finalizer Type" subsection in the ELisp manual for the
2126 ** Lexical closures can use '(:documentation FORM)' to build their docstring.
2127 It should be placed right where the docstring would be, and FORM is then
2128 evaluated (and should return a string) when the closure is built.
2131 ** 'define-inline' provides a new way to define inlinable functions.
2134 ** New function 'macroexpand-1' to perform a single step of macro expansion.
2137 ** Some "x-*" functions were obsoleted and/or renamed:
2138 *** 'x-select-text' is renamed 'gui-select-text'.
2139 *** 'x-selection-value' is renamed 'gui-selection-value'.
2140 *** 'x-get-selection' is renamed 'gui-get-selection'.
2141 *** 'x-get-clipboard' and 'x-clipboard-yank' are marked obsolete.
2142 *** 'x-get-selection-value' is renamed to 'gui-get-primary-selection'.
2143 *** 'x-set-selection' is renamed to 'gui-set-selection'.
2146 ** New function 'string-greaterp', which return the opposite result of
2150 ** The new functions 'string-collate-lessp' and 'string-collate-equalp'
2151 preserve the collation order as defined by the system's locale(1)
2152 environment. For the time being this is implemented for modern POSIX
2153 systems and for MS-Windows, for other systems they fall back to their
2154 counterparts 'string-lessp' and 'string-equal'.
2157 *** The ls-lisp package uses 'string-collate-lessp' to sort file names.
2158 The effect is that, on systems that use ls-lisp for Dired, the default
2159 sort order of the files in Dired is now different from what it was in
2160 previous versions of Emacs. In particular, the file names are sorted
2161 disregarding punctuation, accents, and diacritics, and letter case is
2162 ignored. For example, files whose name begin with a period will no
2163 longer appear near the beginning of the directory listing. If you
2164 want the old, locale-independent sorting, customize the new option
2165 'ls-lisp-use-string-collate' to the nil value.
2168 *** The MS-Windows specific variable 'w32-collate-ignore-punctuation',
2169 if set to a non-nil value, causes the above 2 functions to ignore
2170 symbol and punctuation characters when collating strings. This
2171 emulates the behavior of modern Posix platforms when the locale's
2172 codeset is "UTF-8" (as in "en_US.UTF-8"). This is needed because
2173 MS-Windows doesn't support UTF-8 as codeset in its locales.
2176 ** New function 'alist-get', which is also a valid place (aka lvalue).
2179 ** New function 'funcall-interactively', which works like 'funcall'
2180 but makes 'called-interactively-p' treat the function as (you guessed it)
2181 called interactively.
2184 ** New function 'function-put' to use instead of 'put' for function properties.
2187 ** The new function 'bidi-find-overridden-directionality' allows you to
2188 find characters whose directionality was, perhaps maliciously,
2189 overridden by directional override control characters. Lisp programs
2190 can use this to detect potential phishing of URLs and other links that
2191 exploits bidirectional display reordering.
2194 ** The new function 'buffer-substring-with-bidi-context' allows you to
2195 copy a portion of a buffer into a different location while preserving
2196 the visual appearance both of the copied text and the text at
2197 destination, even when the copied text includes mixed bidirectional
2198 text and directional control characters.
2201 ** New properties that can be specified with 'declare':
2202 *** '(interactive-only INSTEAD)', says to use INSTEAD for non-interactive use.
2203 *** '(pure VAL)', if VAL is non-nil, indicates the function is pure.
2204 *** '(side-effect-free VAL)', if VAL is non-nil, indicates the function does not
2208 ** New macro 'with-file-modes', for evaluating expressions with default file
2209 permissions set to temporary values (e.g., for creating private files).
2212 ** You can access the slots of structures using 'cl-struct-slot-value'.
2215 ** Function 'sort' can deal with vectors.
2218 ** Function 'system-name' now returns an updated value if the current
2219 system's name has changed or if the Emacs process has changed systems.
2220 To avoid long waits it no longer consults DNS to canonicalize the name
2221 (in some cases this may affect generated message-id headers - customize
2222 'message-user-fqdn' if this bothers you). The variable 'system-name'
2226 ** Function 'write-region' no longer outputs "Wrote FILE" in batch mode.
2229 ** If 'pwd' is called with a prefix argument, insert the current default
2233 ** New functions return extended information about fonts and faces.
2236 *** The function 'font-info' now returns more details about a font.
2237 In particular, it now returns the average width of the font's
2238 characters, which can be used for geometry-related calculations.
2241 *** A new function 'default-font-width' returns the average width of a
2242 character in the current buffer's default font. If the default face
2243 is remapped (see 'face-remapping-alist'), the value for the remapped
2244 face is returned. This function complements the existing function
2245 'default-font-height'.
2248 *** New functions 'window-font-height' and 'window-font-width' return
2249 the height and average width of characters in a specified face and
2250 window. If FACE is remapped (see 'face-remapping-alist'), the
2251 function returns the information for the remapped face.
2254 *** A new function 'window-max-chars-per-line' returns the maximal
2255 number of characters that can be displayed on one line. If a face
2256 and/or window are provided, these values are used for the
2257 calculation. This function is different from 'window-body-width' in
2258 that it accounts for (i) continuation glyphs, (ii) the size of the
2259 font, and (iii) the specified window.
2262 ** New utilities in subr-x.el:
2264 *** New macros 'if-let' and 'when-let' allow defining bindings and to
2265 execute code depending whether all values are true.
2267 *** New macros 'thread-first' and 'thread-last' allow threading a form
2268 as the first or last argument of subsequent forms.
2271 ** Documentation strings now support quoting with curved single quotes
2272 in addition to the old style with grave accent and apostrophe. The
2273 new style looks better on today's displays. In the new Electric Quote
2274 mode, you can enter curved single quotes into documentation by typing
2275 grave accent and apostrophe. Outside Electric Quote mode, you can
2276 enter them by typing 'C-x 8 [' and 'C-x 8 ]', or (if your Alt key
2277 works) by typing 'A-[' and 'A-]'. As described above under
2278 'text-quoting-style', the user can specify how to display doc string
2282 ** New function 'format-message' is like 'format' and also converts
2283 curved single quotes, grave accents and apostrophes as per
2284 'text-quoting-style'.
2287 ** 'show-help-function's arg is converted via 'substitute-command-keys'
2288 before being passed to the function. Help strings, help-echo
2289 properties, etc. can therefore contain command key escapes and
2293 ** Time-related changes:
2295 *** Time conversion functions now accept an optional ZONE argument
2296 that specifies the time zone rules for conversion. ZONE is omitted or
2297 nil for Emacs local time, t for Universal Time, 'wall' for system wall
2298 clock time, or a string as in the TZ environment variable. The
2299 affected functions are 'current-time-string', 'current-time-zone',
2300 'decode-time', and 'format-time-string'. The function 'encode-time',
2301 which already accepted a simple time zone rule argument, has been
2302 extended to accept all the new forms.
2304 *** Incompatible change in the third argument of 'format-time-string'.
2305 Previously, any non-nil argument was interpreted as specifying Universal Time.
2306 This is no longer true; packages that want Universal Time should pass t
2307 as the third argument.
2309 *** Time-related functions now consistently accept numbers
2310 (representing seconds since the epoch) and nil (representing the
2311 current time) as well as the usual list-of-integer representation.
2312 Affected functions include 'current-time-string', 'current-time-zone',
2313 'decode-time', 'float-time', 'format-time-string', 'seconds-to-time',
2314 'time-add', 'time-less-p', 'time-subtract', 'time-to-day-in-year',
2315 'time-to-days', and 'time-to-seconds'.
2317 *** The 'encode-time-value' and 'with-decoded-time-value' macros have
2320 *** 'calendar-next-time-zone-transition', 'time-add', and
2321 'time-subtract' no longer return time values in the obsolete and
2322 undocumented integer-pair format. Instead, they return a list of two
2326 ** New function 'set-binary-mode' allows switching a standard stream
2327 of the Emacs process to binary I/O mode.
2330 ** The new function 'directory-name-p' can be used to check whether a file
2331 name (as returned from, for instance, 'file-name-all-completions') is
2332 a directory file name. It returns non-nil if the last character in
2333 the name is a directory separator character (forward slash on GNU and
2334 Unix systems, forward- or backslash on MS-Windows and MS-DOS).
2337 ** ASCII approximations to curved quotes are put in 'standard-display-table'
2338 if the terminal cannot display curved quotes.
2341 ** Standard output and error streams now transliterate characters via
2342 'standard-display-table', and encode output using 'locale-coding-system'.
2343 To force a specific encoding, bind 'coding-system-for-write' to the
2344 coding-system of your choice when invoking functions like 'prin1' and
2348 ** New var 'truncate-string-ellipsis' to choose how to indicate truncation.
2351 ** New possible value for 'system-type': 'nacl'.
2352 This is used by Google's Native Client (NaCl).
2354 ** Miscellaneous name change
2357 For consistency with the usual Emacs spelling, the Lisp variable
2358 'hfy-optimisations' has been renamed to 'hfy-optimizations'.
2359 The old name should still work, as an obsolescent alias.
2361 ** Changes in Frame- and Window- Handling
2364 *** Emacs can now draw horizontal scroll bars on some platforms that
2365 provide toolkit scroll bars, namely Gtk+, Lucid, Motif and Windows.
2366 Horizontal scroll bars are turned off by default.
2368 **** New function 'horizontal-scroll-bars-available-p' telling whether
2369 horizontal scroll bars are available on the underlying system.
2371 **** New mode 'horizontal-scroll-bar-mode' to toggle horizontal scroll
2372 bars on all existing and future frames.
2374 **** New function 'toggle-horizontal-scroll-bar' to toggle horizontal
2375 scroll bars on the selected frame.
2377 **** New frame parameters 'horizontal-scroll-bars' and
2378 'scroll-bar-height' to set horizontal scroll bars and their height
2379 for individual frames and in 'default-frame-alist'.
2381 **** New functions 'frame-scroll-bar-height' and
2382 'window-scroll-bar-height' return the height of horizontal scroll
2383 bars on a specific frame or window.
2385 **** 'set-window-scroll-bars' now accepts five parameters where the last
2386 two specify height and type of the window's horizontal scroll bar.
2388 **** 'window-scroll-bars' now returns type and sizes of horizontal scroll
2391 **** New buffer-local variables 'horizontal-scroll-bar' and
2392 'scroll-bar-height'.
2395 *** New functions 'frame-geometry' and 'frame-edges' give access to a
2399 *** New functions 'mouse-absolute-pixel-position' and
2400 'set-mouse-absolute-pixel-position' get/set screen coordinates of the
2404 *** The function 'window-edges' now accepts three additional arguments to
2405 retrieve body, absolute and pixel edges of the window.
2408 *** The functions 'window-inside-edges', 'window-inside-pixel-edges' and
2409 'window-inside-absolute-pixel-edges' have been renamed to respectively
2410 'window-body-edges', 'window-body-pixel-edges' and
2411 'window-absolute-body-pixel-edges'. The old names are kept as aliases.
2414 *** New function 'window-absolute-pixel-position' to get the screen
2415 coordinates of a visible buffer position.
2418 *** The height of a frame's menu and tool bar are no longer counted in the
2419 frame's text height. This means that the text height stands only for
2420 the height of the frame's root window plus that of the echo area (if
2421 present). This was already the behavior for frames with external tool
2422 and menu bars (like in the Gtk builds) but has now been extended to all
2426 *** Frames now do not necessarily preserve the number of columns or lines
2427 they display when setting default font, menu bar, fringe width, or
2428 scroll bars. In particular, maximized and fullscreen frames are
2429 conceptually never resized if such settings change. For fullheight and
2430 fullwidth frames, the behavior may depend on the toolkit used.
2432 **** New option 'frame-inhibit-implied-resize' if non-nil, means that
2433 setting default font, menu bar, fringe width, or scroll bars of a
2434 specific frame does not resize that frame in order to preserve the
2435 number of columns or lines it displays.
2438 *** New function 'window-preserve-size' allows you to preserve the size of
2439 a window without "fixing" it. It's supported by 'fit-window-to-buffer',
2440 'temp-buffer-resize-mode' and 'display-buffer'.
2443 *** New 'display-buffer' action function 'display-buffer-use-some-frame'.
2444 This displays the buffer in an existing frame other than the current
2445 frame, and allows the caller to specify a frame predicate to exclude
2449 *** New minor mode 'window-divider-mode' and options
2450 'window-divider-default-places', 'window-divider-default-bottom-width'
2451 and 'window-divider-default-right-width'.
2454 *** The window displaying the '*Completions*' buffer with minibuffer
2455 completion candidates is now shown at the bottom of the selected
2456 frame. The size of that window is always as large as required to
2457 display all the candidates, except when limited by the minimum size
2458 of the other windows on that frame; those other windows are resized
2459 to provide space for the '*Completions*' display. The Emacs manual
2460 describes how to customize 'display-buffer-alist' to get back the old
2461 behavior, see the node "Temporary Displays" there.
2464 ** Tearoff menus and detachable toolbars for Gtk+ have been removed.
2465 Those features have been deprecated in Gtk+ for a long time.
2470 *** etags no longer qualifies class members by default.
2472 By default, 'etags' will not qualify class members for Perl and C-like
2473 object-oriented languages with their class names and namespaces, and
2474 will remove qualifications used explicitly in the code from the tag
2475 names it puts in TAGS files. This is so the etags.el back-end for
2476 'xref-find-definitions' is more accurate and produces less false
2479 Use --class-qualify (-Q) if you want the old default behavior of
2480 qualifying class members in C++, Java, Objective C, and Perl. Note
2481 that using -Q might make some class members become "unknown" to 'M-.'
2482 ('xref-find-definitions'); if so, you can use 'C-u M-.' to specify the
2483 qualified names by hand.
2486 *** New language Ruby
2488 Names of modules, classes, methods, functions, and constants are
2489 tagged. Overloaded operators are also tagged.
2493 Names of packages, functions, and types are tagged.
2496 *** Improved support for Lua
2498 Etags now tags functions even if the "function" keyword follows some
2499 whitespace at line beginning.
2502 * Changes in Emacs 25.1 on Non-Free Operating Systems
2505 ** MS-Windows specific Emacs build scripts are no longer in the distribution.
2506 This includes the makefile.w32-in files in various subdirectories, and
2507 the support files. The file nt/configure.bat now just tells the user
2508 to use the procedure described in nt/INSTALL, by running the Posix
2509 'configure' script in the top-level directory.
2512 ** Building Emacs for MS-Windows requires at least Windows XP
2513 or Windows Server 2003. The built binaries still run on all versions
2514 of Windows starting with Windows 9X.
2517 ** Emacs running on MS-Windows now supports the daemon mode.
2520 ** The byte counts in etags-generated TAGS files are now the same on
2521 MS-Windows as they are on other platforms.
2524 ** On OS X, configure creates a Cocoa ("Nextstep") build by default.
2525 Pass '--without-ns' to configure to create an X11 build, the old default.
2528 ** OS X 10.5 or older is no longer supported.
2531 ** OS X on PowerPC is no longer supported.
2534 ** New variable 'ns-use-fullscreen-animation' controls animation for
2535 non-native NS fullscreen. The default is nil. Set to t to enable
2536 animation when entering and leaving fullscreen. For native OSX fullscreen
2539 ** On the OS X Cocoa ("Nextstep") port, multicolor font (such as color
2540 emoji) display is disabled. This feature was accidentally added when
2541 Emacs 24.4 included the new Core Text based font backend code that was
2542 originally implemented for a non-mainline port. This will be enabled
2543 again once it is also implemented in Emacs on free operating systems.
2544 If some symbols, such as emoji, do not display, we suggest to install
2545 an appropriate font, such as Symbola; then they will be displayed,
2546 albeit without the color effects.
2549 ** The new function 'w32-application-type' returns the type of an
2550 MS-Windows application given the name of its executable program file.
2552 ** New variable 'w32-pipe-buffer-size'.
2553 It can be used to tune the size of the buffer of pipes created for
2554 communicating with subprocesses, when the program run by a subprocess
2555 exhibits unusual buffering behavior. Default is zero, which lets the
2556 OS use its default size.
2559 ----------------------------------------------------------------------
2560 This file is part of GNU Emacs.
2562 GNU Emacs is free software: you can redistribute it and/or modify
2563 it under the terms of the GNU General Public License as published by
2564 the Free Software Foundation, either version 3 of the License, or
2565 (at your option) any later version.
2567 GNU Emacs is distributed in the hope that it will be useful,
2568 but WITHOUT ANY WARRANTY; without even the implied warranty of
2569 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
2570 GNU General Public License for more details.
2572 You should have received a copy of the GNU General Public License
2573 along with GNU Emacs. If not, see <http://www.gnu.org/licenses/>.
2579 paragraph-separate: "[
\f]*$"