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 compute a fast, non-consing
107 hash of a buffer's contents.
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
364 * Incompatible Lisp Changes in Emacs 25.2
367 ** Resizing a frame no longer runs 'window-configuration-change-hook'.
368 Put your function on 'window-size-change-functions' instead.
370 ** 'C-up', 'C-down', 'C-left' and 'C-right' are now defined in term
371 mode to send the same escape sequences that xterm does. This makes
372 things like forward-word in readline work.
375 ** hideshow mode got four key bindings that are analogous to outline
376 mode bindings: 'C-c @ C-a', 'C-c @ C-t', 'C-c @ C-d', and 'C-c @ C-e.'
378 ** The grep/rgrep/lgrep functions will now ask about saving files
379 before running. This is controlled by the 'grep-save-buffers'
383 ** The variable 'text-quoting-style' no longer affects the treatment
384 of curved quotes in format arguments to functions like 'message' and
385 'format-message'. In particular, when this variable's value is
386 'grave', all quotes in formats are output as-is.
388 ** Functions like 'check-declare-file' and 'check-declare-directory'
389 now generate less chatter and more-compact diagnostics. The auxiliary
390 function 'check-declare-errmsg' has been removed.
393 * Lisp Changes in Emacs 25.2
395 ** New var `definition-prefixes' is a hashtable mapping prefixes to the
396 files where corresponding definitions can be found. This can be used
397 to fetch definitions that are not yet loaded, for example for `C-h f'.
399 ** New var syntax-ppss-table to control the syntax-table used in syntax-ppss.
402 ** 'define-derived-mode' can now specify an :after-hook form, which
403 gets evaluated after the new mode's hook has run. This can be used to
404 incorporate configuration changes made in the mode hook into the
407 ** Autoload files can be generated without timestamps,
408 by setting 'autoload-timestamps' to nil.
409 FIXME As an experiment, nil is the current default.
410 If no insurmountable problems before next release, it can stay that way.
412 ** 'ert-with-function-mocked' of 'ert-x package allows mocking of functions
416 ** 'gnutls-boot' now takes a parameter :complete-negotiation that says
417 that negotiation should complete even on non-blocking sockets.
420 ** New functions 'window-pixel-width-before-size-change' and
421 'window-pixel-height-before-size-change' support detecting which
422 window changed size when 'window-size-change-functions' are run.
425 ** New function 'display-buffer-reuse-mode-window' is an action function
426 suitable for use in 'display-buffer-alist'. For example, to avoid creating
427 a new window when opening man pages when there's already one, use
428 (add-to-list 'display-buffer-alist
429 '("\\`\\*Man .*\\*\\'" .
430 (display-buffer-reuse-mode-window
431 (inhibit-same-window . nil)
435 ** There is now a new variable 'flyspell-sort-corrections-function'
436 that allows changing the way corrections are sorted.
439 ** The new command 'fortune-message' has been added, which displays
440 fortunes in the echo area.
443 ** New function 'func-arity' returns information about the argument list
444 of an arbitrary function. This generalizes 'subr-arity' for functions
445 that are not built-in primitives. We recommend using this new
446 function instead of 'subr-arity'.
449 ** 'parse-partial-sexp' state has a new element. Element 10 is
450 non-nil when the last character scanned might be the first character
451 of a two character construct, i.e., a comment delimiter or escaped
452 character. Its value is the syntax of that last character.
455 ** 'parse-partial-sexp''s state, element 9, has now been confirmed as
456 permanent and documented, and may be used by Lisp programs. Its value
457 is a list of currently open parenthesis positions, starting with the
458 outermost parenthesis.
461 ** 'read-color' will now display the color names using the color itself
462 as the background color.
464 ** The function 'redirect-debugging-output' now works on platforms
465 other than GNU/Linux.
468 ** The new function 'string-version-lessp' compares strings by
469 interpreting consecutive runs of numerical characters as numbers, and
470 compares their numerical values. According to this predicate,
471 "foo2.png" is smaller than "foo12.png".
474 ** The new function 'char-from-name' converts a Unicode name string
475 to the corresponding character code.
478 ** New functions 'sxhash-eq' and 'sxhash-eql' return hash codes of a
479 Lisp object suitable for use with 'eq' and 'eql' correspondingly. If
480 two objects are 'eq' ('eql'), then the result of 'sxhash-eq'
481 ('sxhash-eql') on them will be the same.
484 ** Function 'sxhash' has been renamed to 'sxhash-equal' for
485 consistency with the new functions. For compatibility, 'sxhash'
486 remains as an alias to 'sxhash-equal'.
489 ** Time conversion functions that accept a time zone rule argument now
490 allow it to be OFFSET or a list (OFFSET ABBR), where the integer
491 OFFSET is a count of seconds east of Universal Time, and the string
492 ABBR is a time zone abbreviation. The affected functions are
493 'current-time-string', 'current-time-zone', 'decode-time',
494 'format-time-string', and 'set-time-zone-rule'.
497 *** New basic face 'fixed-pitch-serif', for a fixed-width font with serifs.
498 The Info-quoted and tex-verbatim faces now default to inheriting from it.
501 * Changes in Emacs 25.2 on Non-Free Operating Systems
503 ** Intercepting hotkeys on Windows 7 and later now works better.
504 The new keyboard hooking code properly grabs system hotkeys such as
505 Win-* and Alt-TAB, in a way that Emacs can get at them before the
506 system. This makes the 'w32-register-hot-key' functionality work
507 again on all versions of MS-Windows starting with Windows 7. On
508 Windows NT and later you can now register any hotkey combination. (On
509 Windows 9X, the previous limitations, spelled out in the Emacs manual,
512 ** 'convert-standard-filename' no longer mirrors slashes on MS-Windows.
513 Previously, on MS-Windows this function converted slash characters in
514 file names into backslashes. It no longer does that.
517 * Installation Changes in Emacs 25.1
520 ** Building Emacs now requires C99 or later.
523 ** Building Emacs now requires GNU make, version 3.81 or later.
526 ** New configure option --with-cairo.
527 This builds Emacs with Cairo drawing. As a side effect, it provides
528 support for built-in printing, when Emacs was built with GTK+.
529 Cairo drawing is an experimental feature in Emacs, and subject to
530 change in future releases.
533 ** New configure option --with-modules.
534 This enables support for loading dynamic modules; see below.
537 ** By default, Emacs no longer works on IRIX. We expect that Emacs
538 users are not affected by this, as SGI stopped supporting IRIX in
539 December 2013. If you are affected, please send a bug report. You
540 should be able to work around the problem either by porting the Emacs
541 undumping code to GCC under IRIX, or by configuring --with-wide-int,
542 or by sticking with Emacs 24.4.
545 ** The Emacs garbage collector assumes GC_MARK_STACK == GC_MAKE_GCPROS_NOOPS.
546 The GC_MAKE_GCPROS_NOOPS stack-marking variant has been the default
547 since Emacs 24.4, and the other variants were undocumented and were
548 obstacles to maintenance and development. GC_MARK_STACK and its
549 related symbols have been removed from the C internals.
552 ** 'configure' now prefers gnustep-config when configuring GNUstep.
553 If gnustep-config is not available, the old heuristics are used.
556 ** 'configure' now prefers inotify to gfile for file notification,
557 unless gfile is explicitly requested via --with-file-notification='gfile'.
560 ** 'configure' detects the kqueue file notification library on *BSD
561 and Mac OS X machines.
564 ** The configure option '--with-pkg-config-prog' has been removed.
565 Use './configure PKG_CONFIG=/full/name/of/pkg-config' if you need to.
568 ** The configure option '--with-mmdf' has been removed.
569 It was no longer useful, as it relied on libraries that are no longer
570 supported, and its presence led to confusion during configuration.
571 This affects only the 'movemail' utility; Emacs itself can still
572 process MMDF-format files as before.
575 ** The configure option '--enable-silent-rules' is now the default,
576 and silent rules are now quieter. To get the old behavior where
577 'make' chatters a lot, configure with '--disable-silent-rules' or
578 build with 'make V=1'.
581 ** The configure option '--with-gameuser' now allows you to specify a
582 group instead of a user if its argument is prefixed by ':' (a colon).
583 This will cause the game score files in "${localstatedir}/games/emacs"
584 to be owned by that group, and the helper program for updating them to
585 be installed setgid. The option now defaults to the 'games' group.
588 ** The 'grep-changelog' script (and its manual page) are no longer included.
589 It has no particular connection to Emacs and has not changed in years,
590 so if you want to use it, you can always take a copy from an older Emacs.
593 ** Emacs 25 comes with a new set of icons.
594 Various resolutions are available as etc/images/icons/hicolor/*/apps/emacs.png.
595 The old Emacs logo icons are available as 'emacs23.png' in the same location.
598 ** New make target 'check-expensive' to run additional tests.
599 This includes all tests which run via "make check", plus additional
600 tests which take more time to perform.
603 * Startup Changes in Emacs 25.1
606 ** When Emacs is given a file as a command line argument and
607 'initial-buffer-choice' is non-nil, display both the file and
608 'initial-buffer-choice'. When Emacs is given more than one file and
609 'initial-buffer-choice' is non-nil, show 'initial-buffer-choice'
610 and '*Buffer List*'. This makes Emacs convenient to use from the
611 command line when 'initial-buffer-choice' is non-nil.
614 ** The value of 'initial-scratch-message' is now treated as a doc string
615 and can contain escape sequences for command keys, quotes, and the like.
618 ** The default height of GUI frames was enlarged.
619 This is so there's enough space in the initial window to display the
620 optional text about recovering crashes sessions, without losing the
621 splash image display.
624 * Changes in Emacs 25.1
627 ** Xwidgets: a new feature for embedding native widgets inside Emacs buffers.
628 If you have gtk3 and webkitgtk3 installed, and Emacs was built with
629 xwidget support, you can access the embedded webkit browser with 'M-x
630 xwidget-webkit-browse-url'. This opens a new buffer with the embedded
631 browser. The buffer will have a new mode, 'xwidget-webkit-mode'
632 (similar to 'image-mode'), which supports the webkit widget.
635 *** New functions for xwidget-webkit mode 'xwidget-webkit-insert-string',
636 'xwidget-webkit-adjust-size-dispatch', 'xwidget-webkit-back',
637 'xwidget-webkit-browse-url', 'xwidget-webkit-reload',
638 'xwidget-webkit-current-url', 'xwidget-webkit-scroll-backward',
639 'xwidget-webkit-scroll-forward', 'xwidget-webkit-scroll-down',
640 'xwidget-webkit-scroll-up'.
643 ** Emacs can now load shared/dynamic libraries (modules).
644 A dynamic Emacs module is a shared library that provides additional
645 functionality for use in Emacs Lisp programs, just like a package
646 written in Emacs Lisp would. The functions 'load', 'require',
647 'load-file', etc. were extended to load such modules, as they do with
648 Emacs Lisp packages. The new variable 'module-file-suffix' holds the
649 system-dependent value of the file-name extension ('.so' on Posix
650 hosts) of the module files.
652 A module should export a C-callable function named
653 'emacs_module_init', which Emacs will call as part of the call to
654 'load' or 'require' which loads the module. It should also export a
655 symbol named 'plugin_is_GPL_compatible' to indicate that its code is
656 released under the GPL or compatible license; Emacs will refuse to
657 load modules that don't export such a symbol.
659 If a module needs to call Emacs functions, it should do so through the
660 API defined and documented in the header file 'emacs-module.h'. Note
661 that any module that provides Lisp-callable functions will have to use
662 Emacs functions such as 'fset' and 'funcall', in order to register its
663 functions with the Emacs Lisp interpreter.
665 Modules can create 'user-ptr' Lisp objects that embed pointers to C
666 structs defined by the module. This is useful for keeping around
667 complex data structures created by a module, to be passed back to the
668 module's functions. User-ptr objects can also have associated
669 "finalizers" -- functions to be run when the object is GC'ed; this is
670 useful for freeing any resources allocated for the underlying data
671 structure, such as memory, open file descriptors, etc. A new
672 predicate 'user-ptrp' returns non-nil if its argument is a 'user-ptr'
675 Loadable modules in Emacs are an experimental feature, and subject to
676 change in future releases. For that reason, their support is disabled
677 by default, and must be enabled by using the '--with-modules' option
681 ** Network security (TLS/SSL certificate validity and the like) is
682 added via the new Network Security Manager (NSM) and controlled via
683 the 'network-security-level' variable.
686 ** 'C-h l' now also lists the commands that were run.
689 ** 'x-select-enable-clipboard' is renamed 'select-enable-clipboard'
690 and 'x-select-enable-primary' is renamed 'select-enable-primary'.
691 Additionally they both now apply to all systems (OSX, GNUstep, Windows, you
692 name it), with the proviso that on some systems (e.g. Windows)
693 'select-enable-primary' is ineffective since the system doesn't
694 have the equivalent of a primary selection.
697 ** New option 'switch-to-buffer-in-dedicated-window' allows you to
698 customize how 'switch-to-buffer' proceeds interactively when the
699 selected window is strongly dedicated to its buffer.
702 ** The option 'even-window-heights' has been renamed to
703 'even-window-sizes' and now handles window widths as well.
706 ** 'terpri' gets an optional arg ENSURE to conditionally output a newline.
709 ** 'insert-register' now leaves point after the inserted text
710 when called interactively. A prefix argument toggles this behavior.
713 ** The new variable 'term-file-aliases' replaces some files from lisp/term.
714 The function 'tty-run-terminal-initialization' consults this variable
715 when deciding what terminal-specific initialization code to run.
718 ** New variable 'system-configuration-features', listing some of the
719 main features that Emacs was compiled with. This is mainly intended
720 for use in Emacs bug reports.
723 ** A password is now hidden also when typed in batch mode. Another
724 hiding character but the default '.' can be used by let-binding the
725 variable 'read-hide-char'.
728 ** The Emacs pseudo-random number generator can be securely seeded.
729 On systems where Emacs can access the system entropy or some other
730 cryptographically secure random stream, it now uses that when 'random'
731 is called with its argument t. This allows cryptographically strong
732 random values; in particular, the Emacs server now uses this facility
733 to produce its authentication key.
736 ** New input methods: 'tamil-dvorak' and 'programmer-dvorak'.
739 * Editing Changes in Emacs 25.1
742 ** 'M-x' suggests shorthands and ignores obsolete commands for completion.
747 *** Successive single-char deletions are collapsed in the undo-log just like
748 successive char insertions. Which commands invoke this behavior is
749 controlled by the new 'undo-auto-amalgamate' function. See the node
750 "Undo" in the ELisp manual for more details.
753 *** The heuristic used to insert 'undo-boundary' after each command
754 has changed, so that if a command causes changes in more than just the
755 current buffer, Emacs now calls 'undo-boundary' in every buffer
756 affected by the command.
759 ** New command 'comment-line' bound to 'C-x C-;'.
761 ** New and improved facilities for inserting Unicode characters
764 *** Unicode names entered via 'C-x 8 RET' now use substring completion
768 *** 'C-x 8' now has shorthands for several chars, such as U+2010
769 (HYPHEN), U+2011 (NON-BREAKING HYPHEN), and U+2012 (FIGURE DASH). As
770 before, you can type 'C-x 8 C-h' to list shorthands.
773 *** New minor mode 'electric-quote-mode' for using curved quotes as you
774 type. See also the new variable 'text-quoting-style'.
777 ** New minor mode 'global-eldoc-mode' is enabled by default.
780 ** Emacs now uses "bracketed paste mode" on text terminals that support it.
781 Bracketed paste mode causes text terminals to wrap pasted text in special
782 escape sequences that allow Emacs to tell the difference between text
783 you type and text you paste from other applications. Emacs then
784 avoids interpreting each character in the pasted text as it does with
785 keyboard input, which results in a paste experience similar to that
786 under a window system, and significant performance improvements when
787 pasting large amounts of text.
789 Bracketed paste mode is disabled by default, so Emacs automatically
790 enables it at startup if the terminal supports it.
793 ** Emacs now supports the latest version of the UBA.
794 The Emacs implementation of the Unicode Bidirectional Algorithm (UBA)
795 was updated to support all the latest additions and changes introduced
796 in Unicode Standard versions 6.3, 7.0, and the latest Unicode 8.0.
797 This includes full support for directional isolates and the
798 Bidirectional Parentheses Algorithm (BPA) specified by these Unicode
802 ** You can access 'mouse-buffer-menu' ('C-down-mouse-1') using 'C-f10'.
805 ** New buffer-local 'electric-pair-local-mode'.
808 ** New variable 'fast-but-imprecise-scrolling' inhibits
809 fontification during full screen scrolling operations, giving less
810 hesitant operation during auto-repeat of 'C-v', 'M-v' at the cost of
811 possible inaccuracies in the end position.
814 ** New documentation command 'describe-symbol'.
815 Works for functions, variables, faces, etc. It is bound to 'C-h o' by
819 ** New function 'custom-prompt-customize-unsaved-options' checks for
820 unsaved customizations and prompts user to customize (if found). It
821 is intended for adding to 'kill-emacs-query-functions'.
824 ** The old 'C-x w' bindings in 'hi-lock-mode' are officially deprecated
825 in favor of the global 'M-s h' bindings introduced in Emacs 23.1.
826 They'll disappear soon.
829 * Changes in Specialized Modes and Packages in Emacs 25.1
834 *** New command 'checkdoc-package-keywords' checks if the
835 current package keywords are recognized. Set the new option
836 'checkdoc-package-keywords-flag' to non-nil to make
837 'checkdoc-current-buffer' call this function automatically.
840 *** New function 'checkdoc-file' checks for style errors.
841 It's meant for use together with 'compile':
842 emacs -batch --eval "(checkdoc-file \"subr.el\")"
847 *** The desktop format version has been upgraded from 206 to 208.
848 Although Emacs 25.1 can read a version 206 desktop, earlier Emacsen
849 cannot read a version 208 desktop. To upgrade your desktop file, you
850 must explicitly request the upgrade, by 'C-u M-x desktop-save'. You are
851 recommended to do this as soon as you have firmly upgraded to Emacs
852 25.1 (or later). Should you ever need to downgrade your desktop file
853 to version 206, you can do this with 'C-u C-u M-x desktop-save'.
856 ** New function 'bookmark-set-no-overwrite' bound to 'C-x r M'.
857 It raises an error if a bookmark of that name already exists,
858 unlike 'bookmark-set' which silently updates an existing bookmark.
863 *** New user options 'mm-html-inhibit-images' and 'mm-html-blocked-images'
864 now control how mm-* functions fetch and display images in an HTML
865 message. Gnus still uses 'gnus-inhibit-images' and 'gnus-blocked-images'
866 for that purpose, i.e., binds mm-html- variables with those gnus-
867 variables, but other packages do not have to bind gnus- variables now.
870 *** 'mm-inline-text-html-with-images' has been removed.
871 Use 'mm-html-inhibit-images' instead. Note that the value is opposite
877 *** 'imap-ssl-program' has been removed, and imap.el uses the internal
878 GnuTLS encryption functions if possible.
883 *** 'json-pretty-print' and 'json-pretty-print-buffer' now maintain
884 the ordering of object keys by default.
887 *** New commands 'json-pretty-print-ordered' and
888 'json-pretty-print-buffer-ordered' pretty prints JSON objects with
889 object keys sorted alphabetically.
891 ** Prettify Symbols mode
894 *** Prettify Symbols mode supports custom composition predicates. By
895 overriding the default 'prettify-symbols-compose-predicate', modes can
896 specify in which contexts a symbol may be displayed as some Unicode
897 character. 'prettify-symbols-default-compose-p' is the default which
898 is suitable for most programming languages such as C or Lisp (but not
902 *** Symbols can be unprettified while point is inside them.
903 New variable 'prettify-symbols-unprettify-at-point' configures this.
905 ** Enhanced xterm support
908 *** The new variable 'xterm-screen-extra-capabilities' for configuring xterm.
909 This variable tells Emacs which advanced capabilities are available in
910 the xterm terminal emulator used to display Emacs text-mode frames.
911 The default is to check each capability, and use it if available.
912 (This variable was introduced in Emacs 24.1, but was not announced in
916 *** Killing text now also sets the CLIPBOARD/PRIMARY selection
917 in the surrounding GUI (using the OSC-52 escape sequence). This only works
918 if your xterm supports it and enables the 'allowWindowOps' options (disabled
919 by default at least in Debian, for security reasons).
921 Similarly, you can yank the CLIPBOARD/PRIMARY selection (using the OSC-52
922 escape sequence) if your xterm has the feature enabled but for that you
923 additionally need to add 'getSelection' to 'xterm-extra-capabilities'.
926 *** 'xterm-mouse-mode' now supports mouse-tracking (if your xterm supports it).
929 ** The way to turn on and off 'save-place' mode has changed.
930 It is no longer sufficient to load the saveplace library and set
931 'save-place' non-nil. Instead, use the two new minor modes:
932 'save-place-mode' turns on saving last place in every file, and
933 'save-place-local-mode' does that only for the file in whose buffer it
934 is invoked. The 'save-place' variable is now an obsolete alias for
935 'save-place-mode', which replaces it, and 'toggle-save-place' is an
936 obsolete alias for the new 'save-place-local-mode' command.
941 *** ERC can now hide message types by network or channel.
942 'erc-hide-list' will hide all messages of the specified type, while
943 'erc-network-hide-list' and 'erc-channel-hide-list' will only hide the
944 specified message types for the respective specified targets.
947 *** Reconnection is now asynchronous.
950 *** Nick completion is now case-insensitive again after inadvertently
951 being made case-sensitive in Emacs 24.2.
956 *** New commands, key binds, and menu items.
958 **** '<' and '>' for navigating previous and next tracks in playlist
960 **** New play/pause command 'mpc-toggle-play' bound to 's'
962 **** 'g' bound to new command 'mpc-seek-current' will navigate current
965 **** New commands 'mpc-toggle-{consume,repeat,single,shuffle}' for
966 toggling playback modes.
969 *** Now supports connecting to a UNIX domain socket.
972 *** Looks at more image file names to use as album art.
973 Case-insensitively tries for .folder.png (freedesktop) and folder.jpg
974 (XP) in addition to cover.jpg.
977 *** Searches in more locations for MPD configuration files.
978 MPD supports the XDG base directory specification since version 0.17.6.
983 *** 'midnight-mode' is now a proper minor mode.
986 *** clean-buffer-*-regexps can now specify buffers via predicate functions.
991 *** New "external" package status.
992 An external package is any installed package that's not built-in and
993 not from 'package-user-dir', which usually means it's from an entry in
994 'package-directory-list'. They are treated much like built-in
995 packages, in that they cannot be deleted through the package menu and
996 are not considered for upgrades.
998 The effect is that a user can manually place a specific version of a
999 package inside 'package-directory-list' and the package menu will
1000 always respect that.
1003 *** If a package is available on multiple archives and one has higher
1004 priority (as per 'package-archive-priorities') only that one is
1005 listed. This can be configured with 'package-menu-hide-low-priority'.
1008 *** 'package-menu-toggle-hiding' now toggles the hiding of packages.
1009 This includes the above-mentioned low-priority packages, as well as
1010 available packages whose version is lower than the currently installed
1011 version (which were previously impossible to display).
1012 This allows users to downgrade a package if a lower version is
1016 *** When filtering the package menu, keywords starting with "arc:" or
1017 "status:" represent package archive or status, respectively, instead
1021 *** Most functions which involve downloading information now take an
1022 ASYNC argument. If it is non-nil, package.el performs the download(s)
1026 *** New variable 'package-menu-async' controls whether the
1027 package-menu uses asynchronous downloads.
1030 *** 'package-install-from-buffer' and 'package-install-file' work on directories.
1031 This follows the same rules as installing from a .tar file, except the
1032 -pkg file is optional.
1035 *** Packages which are dependencies of other packages cannot be deleted.
1036 The FORCE argument to 'package-delete' overrides this.
1039 *** New custom variable 'package-selected-packages' tracks packages
1040 which were installed by the user (as opposed to installed as
1041 dependencies). This variable can also be manually customized.
1044 *** New command 'package-install-selected-packages' installs all
1045 packages from 'package-selected-packages' which are currently missing.
1048 *** 'package-install' function now takes a DONT-SELECT argument. If
1049 this function is called interactively or if DONT-SELECT is nil, add the
1050 package being installed to 'package-selected-packages'.
1053 *** New command 'package-autoremove' removes all packages which were
1054 installed strictly as dependencies but are no longer needed.
1059 When you invoke 'shell' interactively, the '*shell*' buffer will now
1060 display in a new window. However, you can customize this behavior via
1061 the 'display-buffer-alist' variable. For example, to get
1062 the old behavior -- '*shell*' buffer displays in current window -- use
1063 (add-to-list 'display-buffer-alist
1064 '("^\\*shell\\*$" . (display-buffer-same-window))).
1068 *** The ':protection' slot option is not obeyed any more.
1070 *** The 'newname' argument to constructors is optional&deprecated.
1071 If you need your objects to be named, do it by inheriting from 'eieio-named'.
1073 *** The <class>-list-p and <class>-child-p functions are declared obsolete.
1075 *** The <class> variables are declared obsolete.
1077 *** The <initarg> variables are declared obsolete.
1079 *** defgeneric and defmethod are declared obsolete.
1080 Use the equivalent facilities from cl-generic.el instead.
1082 *** 'constructor' is now an obsolete alias for 'make-instance'.
1084 *** 'pcase' accepts a new UPattern 'eieio'.
1089 *** New command 'ido-bury-buffer-at-head' bound to 'C-S-b'.
1090 Bury the buffer at the head of 'ido-matches', analogous to how 'C-k'
1091 kills the buffer at head.
1094 *** A prefix argument to 'ido-restrict-to-matches' will reverse its
1095 meaning, and the list is restricted to those elements that do not
1096 match the current input.
1101 *** You can use <UP> and <DOWN> arrow keys to move through history by lines.
1102 The new commands 'next-line-or-history-element' and
1103 'previous-line-or-history-element', bound to <UP> and <DOWN> in the
1104 minibuffer, allow by-line movement through minibuffer history,
1105 similarly to an ordinary buffer. Only when point moves over
1106 the bottom/top of the minibuffer it goes to the next/previous history
1107 element. 'M-p' and 'M-n' still move directly to previous/next history
1110 ** Search and Replace
1113 *** 'isearch' and 'query-replace' can now perform character folding in matches.
1114 This is analogous to case folding, but instead of disregarding case
1115 variants, it disregards wider classes of distinctions between similar
1116 characters. (Case folding is a special case of character folding.)
1117 This means many characters in the search string will match entire
1118 groups of characters instead of just themselves.
1120 For instance, the ASCII double quote character " will match all
1121 variants of double quotes, and the letter 'a' will match all of its
1122 accented cousins, even those composed of multiple characters, as well
1123 as many other symbols like U+249C (PARENTHESIZED LATIN SMALL LETTER
1126 Character folding is enabled by customizing 'search-default-mode' to
1127 the value 'char-fold-to-regexp'. You can also toggle character
1128 folding in the middle of a search by typing 'M-s ''.
1130 'query-replace' honors character folding if the new variable
1131 'replace-char-fold' is customized to a non-nil value.
1134 *** New user option 'search-default-mode'.
1135 This option specifies the default mode for Isearch. The default
1136 value, nil specifies that Isearch does literal searches (however,
1137 'case-fold-search' and 'isearch-lax-whitespace' may still be applied,
1138 as in previous Emacs versions).
1141 *** New function 'char-fold-to-regexp' can be used
1142 by searching commands to produce a regexp matching anything that
1143 char-folds into STRING.
1146 *** The new 'M-s M-w' key binding uses eww to search the web for the
1147 text in the region. The search engine to use for this is specified by
1148 the customizable variable 'eww-search-prefix'.
1151 *** 'query-replace' history is enhanced.
1152 When 'query-replace' reads the FROM string from the minibuffer, typing
1153 'M-p' will now show previous replacements as "FROM SEP TO", where FROM
1154 and TO are the original text and its replacement, and SEP is an arrow
1155 string defined by the new variable 'query-replace-from-to-separator'.
1156 To select a prior replacement, type 'M-p' until the desired
1157 replacement appears in the minibuffer, and then exit the minibuffer by
1162 *** If 'quick-calc' is called with a prefix argument, insert the
1163 result of the calculation into the current buffer.
1166 ** In Edebug, you can now set the initial mode with 'C-x C-a C-m'.
1167 With this you can tell Edebug not to stop at the start of the first
1168 instrumented function.
1173 *** New minor mode 'global-eldoc-mode'.
1174 It is turned on by default, and affects '*scratch*' and other buffers
1175 whose major mode supports Emacs Lisp.
1178 *** 'eldoc-documentation-function' now defaults to 'ignore'.
1181 *** 'describe-char-eldoc' displays information about character at point,
1182 and can be used as a default value of 'eldoc-documentation-function'. It is
1183 useful when, for example, one needs to distinguish various spaces - e.g.,
1184 U+00A0 (NO-BREAK SPACE), U+2002 (EN SPACE), and U+2009 (THIN SPACE) - while
1185 using mono-spaced font.
1190 *** HTML can now be rendered using variable-width fonts.
1193 *** A new command 'F' ('eww-toggle-fonts') can be used to toggle
1194 whether to use variable-pitch fonts or not. The user can also
1195 customize the 'shr-use-fonts' variable.
1198 *** A new command 'R' ('eww-readable') will try do identify the main
1199 textual parts of a web page and display only that, leaving menus and
1200 the like off the page.
1203 *** A new command 'D' ('eww-toggle-paragraph-direction') allows you to
1204 toggle the paragraph direction between left-to-right and right-to-left.
1207 *** You can now use several eww buffers in parallel by renaming eww
1208 buffers you want to keep separate.
1211 *** Partial state of the eww buffers (the URIs and the titles of the
1212 pages visited) is now preserved in the desktop file.
1215 *** 'eww-after-render-hook' is now called after eww has rendered
1216 the data in the buffer.
1219 *** The 'eww-reload' command now takes a prefix to not reload via
1220 the net, but just use the local copy of the HTML.
1223 *** The DOM shr and eww uses has been changed to the general Emacs
1224 xml.el/libxml2 DOM, and a new package dom.el has been added to
1225 interact with this DOM. See the Emacs Lisp manual for interface
1229 *** 'mailcap-mime-data' is now consulted when displaying PDF files.
1232 *** The new 'S' command will list all eww buffers, and allow managing
1236 *** https pages with valid certificates have headers marked in green, while
1237 invalid certificates are marked in red.
1242 *** text/html messages that contain inline image parts will be
1243 transformed into multipart/related messages before sending.
1246 ** In Show Paren Mode, a parenthesis can be highlighted when point
1247 stands inside it, and certain parens can be highlighted when point is
1248 at BOL or EOL, or in whitespace there. To enable these, customize,
1249 respectively, 'show-paren-when-point-inside-paren' or
1250 'show-paren-when-point-in-periphery'.
1253 ** If gpg2 exists on the system, it is now used as the default value
1254 of 'epg-gpg-program' (instead of gpg).
1259 *** Strings after ':documentation' are highlighted as docstrings.
1260 This enhances Lisp mode fontification to handle documentation of the
1261 form '(:documentation "the doc string")' used in Common Lisp code for
1262 CLOS class and slot documentation.
1264 ** Rectangle editing
1267 *** Rectangle Mark mode can have corners past EOL or in the middle of a TAB.
1270 *** 'C-x C-x' in 'rectangle-mark-mode' now cycles through the four corners.
1271 *** 'string-rectangle' provides on-the-fly preview of the result.
1274 ** New font-lock functions 'font-lock-ensure' and 'font-lock-flush'.
1275 These should be used in preference to 'font-lock-fontify-buffer' when
1279 ** Macro 'minibuffer-with-setup-hook' can optionally append a function
1280 to 'minibuffer-setup-hook'.
1282 If the first argument of the macro is of the form '(:append FUN)',
1283 then FUN will be appended to 'minibuffer-setup-hook', instead of
1288 *** New functions 'cl-fresh-line', 'cl-digit-char-p', and 'cl-parse-integer'.
1291 *** 'pcase' accepts the new UPattern 'cl-struct'.
1293 ** Calendar and diary
1296 *** The default 'diary-file' is now located in "~/.emacs.d".
1299 *** New commands to insert diary entries with Chinese dates:
1300 'diary-chinese-insert-anniversary-entry' 'diary-chinese-insert-entry'
1301 'diary-chinese-insert-monthly-entry', 'diary-chinese-insert-yearly-entry'.
1304 *** The calendar can now list and mark diary entries with Chinese dates.
1305 See 'diary-chinese-list-entries' and 'diary-chinese-mark-entries'.
1308 *** The option 'calendar-mode-line-format' can now be nil,
1309 which means to do nothing special with the mode line in calendars.
1312 *** New option 'calendar-weekend-days'.
1313 The option customizes which day headers receive the
1314 'calendar-weekend-header' face.
1317 *** New optional args N and STRING for 'holiday-greek-orthodox-easter'.
1320 *** Many items obsolete since at least version 23.1 have been removed.
1321 The majority were function/variable/face aliases, too numerous to list here.
1324 **** Functions 'calendar-one-frame-setup', 'calendar-only-one-frame-setup',
1325 'calendar-two-frame-setup', 'european-calendar', 'american-calendar'.
1327 **** Hooks 'cal-menu-load-hook', 'cal-x-load-hook'.
1329 **** Macro 'calendar-for-loop'.
1331 **** Variables 'european-calendar-style', 'diary-face', 'hebrew-holidays-{1,4}'.
1333 **** The nil and list forms of 'diary-display-function'.
1336 ** New ERT function 'ert-summarize-tests-batch-and-exit'.
1337 If the output of ERT tests in batch mode execution can be saved to a
1338 log file, then it can be passed as an argument to the above function
1339 to produce a neat summary.
1342 ** New js.el option 'js-indent-first-init'.
1347 ** Info mode now displays symbol names in fixed-pitch font.
1348 If you want to get the old behavior back, customize the 'Info-quoted'
1349 face to use the same definitions as the default face.
1352 *** 'Info-fontify-maximum-menu-size' can be t for no limit.
1355 *** 'info-display-manual' can now be given a prefix argument which (any
1356 non-nil value) directs the command to limit the completion
1357 alternatives to currently visited manuals.
1360 ** ntlm.el has support for NTLM2.
1365 *** The Rmail commands 'd', 'C-d' and 'u' take optional repeat counts
1366 to delete or undelete multiple messages.
1369 *** Rmail can now render HTML mail messages if your Emacs was built with
1370 libxml2 or if you have the Lynx browser installed. By default, Rmail
1371 will display the HTML version of a mail message that has both HTML and
1372 plain text parts, if display of HTML email is possible; customize the
1373 'rmail-mime-prefer-html' option to nil if you don't want that.
1376 *** In the commands that make summaries by subject, recipients, or senders,
1377 you can no longer use commas to separate regular expressions.
1380 ** SES now supports local printer functions; see 'ses-define-local-printer'.
1382 ** Shell-script Mode
1384 *** In sh-mode you can now use 'sh-shell' as a file-local variable to
1385 specify the type of shell in use (bash, csh, etc).
1388 *** New value 'always' for 'sh-indent-after-continuation'.
1389 This provides old-style ("dumb") indentation of continued lines.
1390 See the doc string of 'sh-indent-after-continuation' for details.
1394 *** Fatal TLS errors are now silent by default.
1397 *** If Emacs isn't built with TLS support, an external TLS-capable
1398 program is used instead. This program used to be run in --insecure
1399 mode by default, but has now changed to be secure instead, and will
1400 fail if you try to connect to non-verifiable hosts. This is
1401 controlled by the 'tls-program' variable.
1406 *** The URL package accepts now the protocols "ssh", "scp" and "rsync".
1407 When 'url-handler-mode' is enabled, file operations for these
1408 protocols as well as for "telnet" and "ftp" are passed to Tramp.
1411 *** The URL package allows customizing the 'url-user-agent' string.
1412 The new 'url-user-agent' variable can be customized to be a string or
1416 *** The new interface variable 'url-request-noninteractive' can be used
1417 to specify that we're running in a noninteractive context, and that
1418 we should not be queried about things like TLS certificate validity.
1421 *** 'url-mime-accept-string' can now be used as in "interface"
1422 variable, meaning you can bind it around an 'url-retrieve' call.
1425 *** If URL is used with a https connection, the first callback argument
1426 PLIST will contain a :peer element that has the output of
1427 'gnutls-peer-status' (if Emacs is built with GnuTLS support).
1432 *** New connection method "afp", which allows you to access Mac OS X
1433 volumes via the Apple Filing Protocol.
1436 *** New connection method "nc", which allows you to access dumb
1440 *** Method-specific parameters can be overwritten now with variable
1441 'tramp-connection-properties'.
1444 *** Handler for 'file-notify-valid-p' for remote machines that support
1445 filesystem notifications.
1450 *** New user variable 'sql-default-directory' enables remote
1451 connections using Tramp.
1454 *** New command 'sql-send-line-and-next'.
1455 This command, bound to 'C-c C-n' by default, sends the current line to
1456 the SQL process and advances to the next line, skipping whitespace and
1460 *** Added support for Vertica SQL.
1462 ** VC and related modes
1465 *** Basic push support, via 'vc-push', bound to 'C-x v P'.
1466 Implemented for Bzr, Git, Hg. As part of this change, the pre-existing
1467 (undocumented) command 'vc-hg-push' now behaves slightly differently.
1470 *** The new command 'vc-region-history' shows the log+diff of the active region.
1473 *** You can refresh the VC state of a file buffer with 'M-x vc-refresh-state'.
1474 This command is useful when you perform version control commands
1475 outside Emacs (e.g., from the shell prompt), or if you switch the VC
1476 back-end for the buffer's file, or remove it from version control.
1479 *** New option 'vc-annotate-background-mode' controls whether
1480 the color range from 'vc-annotate-color-map' is applied to the
1481 background or to the foreground.
1484 *** New options for customizing encoding of Git commit log messages.
1485 The new user options 'vc-git-commits-coding-system' and
1486 'vc-git-log-output-coding-system' specify the encoding of log messages
1487 sent to Git when committing, and the decoding of log messages read
1488 from Git history commands. These options default to UTF-8; if
1489 customized, they should be consistent with the Git config variables
1490 i18n.commitEncoding and i18n.logOutputEncoding.
1491 ('vc-git-commits-coding-system' existed previously, but was a
1492 variable, not a user option.)
1495 *** 'compare-windows' now compares text with the most recently selected window
1496 instead of the next window. If you want the previous behavior of
1497 comparing with the next window, customize the new option
1498 'compare-windows-get-window-function' to the value
1499 'compare-windows-get-next-window'.
1502 *** Two new faces 'compare-windows-removed' and 'compare-windows-added'
1503 replace the face 'compare-windows', which is now an obsolete alias for
1504 'compare-windows-added'.
1507 *** The VC state indicator in the mode line now has different faces
1508 corresponding to each of the possible states. See the 'vc-faces'
1509 customization group.
1512 *** 'log-edit-insert-changelog' converts "(tiny change)" to
1513 "Copyright-paperwork-exempt: yes". Set 'log-edit-rewrite-tiny-change'
1514 nil to disable this.
1517 *** vc-mcvs.el has been removed.
1520 ** VHDL mode now supports VHDL'08.
1525 *** Decimal display mode uses "," groups, so it's more
1526 fitting for use in money calculations
1529 *** Factorial works with non-integer inputs.
1534 *** Hide-IfDef mode now support full C/C++ expressions in macros,
1535 macro argument expansion, interactive macro evaluation and automatic
1536 scanning of #define'd symbols.
1539 *** New command 'hif-evaluate-macro', bound to 'C-c @ e', displays the
1540 result of evaluating a macro.
1543 *** New command 'hif-clear-all-ifdef-define', bound to 'C-c @ C', clears
1544 all defined symbols in 'hide-ifdef-env'.
1547 *** New custom variable 'hide-ifdef-header-regexp' to define C/C++ header
1548 file name patterns. Defaults to files whose extension is one of '.h',
1549 '.hh', '.hpp', '.hxx', or '.h++', matched case-insensitively.
1552 *** New custom variable 'hide-ifdef-expand-reinclusion-protection' to prevent
1553 reinclusion protected (a.k.a. "idempotent") header files from being hidden.
1554 (This could happen when an idempotent header file is visited again,
1555 when its guard symbol is already defined.) Defaults to t.
1558 *** New custom variable 'hide-ifdef-exclude-define-regexp' to define symbol
1559 name patterns (e.g. all "FOR_DOXYGEN_ONLY_*") to be ignored when
1560 looking for macro definitions. By default, no symbols are ignored.
1565 *** New custom variable 'tex-print-file-extension' to help users who
1566 use PDF instead of DVI.
1569 *** TeX mode now supports Prettify Symbols mode. When enabling
1570 'prettify-symbols-mode' in a tex-mode buffer, \alpha ... \omega, and
1571 many other math macros are displayed using unicode characters.
1574 ** New 'big-indent' style in 'whitespace-mode' highlights deep indentation.
1575 By default, 32 consecutive spaces or four consecutive TABs are
1576 considered to be too deep, but the new variable
1577 'whitespace-big-indent-regexp' can be customized to change that.
1580 ** New options in 'tildify-mode'.
1581 New options 'tildify-space-string', 'tildify-pattern', and
1582 'tildify-foreach-region-function' variables make
1583 'tildify-string-alist', 'tildify-pattern-alist', and
1584 'tildify-ignored-environments-alist' variables (as well as a few
1585 helper functions) obsolete.
1588 ** New package Xref replaces Etags's front-end and UI.
1590 The new package Xref provides a generic framework and new commands to
1591 find and move to definitions of functions, macros, data structures
1592 etc., as well as go back to the location where you were before moving
1593 to a definition. It supersedes and obsoletes many Etags commands,
1594 while still using the etags.el code that reads the TAGS tables as one
1597 The command 'xref-find-definitions' replaces 'find-tag' and provides
1598 an interface to pick one definition among several.
1599 'tags-loop-continue' is now unbound. 'xref-pop-marker-stack' replaces
1600 'pop-tag-mark', but has a keybinding ('M-,') different from the one
1601 'pop-tag-mark' used.
1603 'xref-find-definitions-other-window' replaces 'find-tag-other-window'.
1604 'xref-find-definitions-other-frame' replaces 'find-tag-other-frame'.
1605 'xref-find-apropos' replaces 'find-tag-regexp'.
1607 As a result of this, the following commands are now obsolete:
1608 'find-tag-other-window', 'find-tag-other-frame', 'find-tag-regexp',
1611 'tags-loop-continue' is not obsolete because it's still useful in
1612 'tags-search' and 'tags-query-replace', for which there are no direct
1616 *** Variants of 'tags-search' and 'tags-query-replace' in Dired were also
1617 replaced by xref-style commands, see the "Dired" section below.
1622 'find-tag-marker-ring-length' is now an obsolete alias for
1623 'xref-marker-ring-length'. 'find-tag-marker-ring' is now an obsolete
1624 alias for a private variable. 'xref-push-marker-stack' and
1625 'xref-pop-marker-stack' should be used instead to manipulate the stack
1626 of searches for definitions.
1629 *** 'xref-find-definitions' and 'describe-function' now display
1630 information about mode local overrides (defined by cedet/mode-local.el
1631 'define-overloadable-function' 'define-mode-local-overrides').
1633 The framework's Lisp API is still experimental and can change in major,
1634 backward-incompatible ways.
1637 ** New package Project
1639 The new package Project provides generic infrastructure for dealing
1640 with projects. The main commands included in it are
1641 'project-find-file' and 'project-find-regexp'.
1643 The Lisp API of this package is still experimental.
1646 EUDC's LDAP backend has been improved.
1649 *** EUDC supports LDAP-over-SSL URLs (ldaps://).
1652 *** EUDC passes LDAP passwords through a pipe to the ldapsearch
1653 subprocess instead of on the command line.
1656 *** EUDC handles LDAP wildcards automatically so the user shouldn't
1657 need to configure this manually anymore.
1660 *** The LDAP configuration section of EUDC's manual has been
1663 There have also been customization changes.
1666 *** New custom variable 'eudc-server-hotlist' to allow specifying
1667 multiple EUDC servers in init file.
1670 *** Custom variable 'eudc-inline-query-format' defaults to completing
1671 on email and firstname instead of surname.
1674 *** Custom variable 'eudc-expansion-overwrites-query' defaults to nil
1675 to avoid interfering with the kill ring.
1678 *** Custom variable 'eudc-inline-expansion-format' defaults to
1679 "Firstname Surname <mail-address>".
1682 *** Custom variable 'eudc-options-file' defaults to
1683 "~/.emacs.d/eudc-options".
1686 *** New custom variable 'ldap-ldapsearch-password-prompt-regexp' to
1687 allow overriding the regular expression that recognizes the ldapsearch
1688 command line's password prompt.
1691 EUDC's BBDB backend now supports BBDB 3.
1694 EUDC's PH backend (eudcb-ph.el) is obsolete.
1699 *** The new built-in command 'clear' can scroll window contents out of sight.
1700 If provided with an optional non-nil argument, the scrollback contents
1704 *** New buffer syntax '#<buffer-name>', which is equivalent to
1705 '#<buffer buffer-name>'. This shorthand makes interacting with
1706 buffers from eshell more convenient. Custom variable
1707 'eshell-buffer-shorthand', which has been broken for a while, has been
1711 *** By default, eshell "visual" program buffers (created by
1712 'eshell-visual-commands' and similar custom vars) are no longer killed
1713 when their processes die. This fixes issues with short-lived commands
1714 and makes visual programs more useful in general. For example, if
1715 "git log" is a visual command, it will always show the visual command
1716 buffer, even if the "git log" process dies. For the old behavior,
1717 make the new option 'eshell-destroy-buffer-when-process-dies' non-nil.
1722 *** Support for the Google Chrome web browser.
1725 *** Support for the Conkeror web browser.
1728 *** Support for several ancient browsers is now officially obsolete.
1731 ** 'tar-mode': new 'tar-new-entry' command, allowing for new members to
1732 be added to the archive.
1737 *** Dired buffers are also auto-reverted via file notifications, if
1738 Emacs is compiled with file notification support.
1741 *** 'auto-revert-use-notify' is set to nil in 'global-auto-revert-mode'.
1742 See <http://debbugs.gnu.org/22814>.
1744 ** File Notifications
1747 *** The kqueue library is integrated for *BSD and Mac OS X machines.
1750 *** The new event 'stopped' signals, that a file notification watch is
1751 not active any longer.
1754 *** The new function 'file-notify-valid-p' checks, whether a file
1755 notification descriptor still corresponds to an activate watch.
1760 *** The command 'dired-do-compress', bound to 'Z', now can compress
1761 directories and decompress zip files.
1764 *** New command 'dired-do-compress-to', bound to 'c', can be used to
1765 compress many marked files into a single named archive. The
1766 compression command is determined from the new
1767 'dired-compress-files-alist' variable.
1770 *** New user interface for the 'A' and 'Q' commands.
1771 These keys, now bound to 'dired-do-find-regexp' and
1772 'dired-do-find-regexp-and-replace', work similarly to 'xref-find-apropos'
1773 and 'xref-query-replace-in-results': they present the matches
1774 in the '*xref*' buffer and let you move through the matches. No need
1775 to use 'tags-loop-continue' to resume the search or replace loop. The
1776 previous commands, 'dired-do-search' and
1777 'dired-do-query-replace-regexp', are still available, but not bound to
1778 keys; rebind 'A' and 'Q' to invoke them if you want the old behavior
1779 back. We intend to obsolete the old commands in a future release.
1781 ** Tabulated List Mode
1784 *** It is now safe for a mode that derives 'tabulated-list-mode' to not
1785 call 'tabulated-list-init-header', in which case it will have no
1789 *** 'tabulated-list-print' takes a second optional argument, UPDATE,
1790 which specifies an alternative printing method which is faster when
1791 few or no entries have changed.
1793 ** Obsolete packages
1799 *** landmark.el (moved to elpa.gnu.org)
1802 * New Modes and Packages in Emacs 25.1
1805 ** pinentry.el allows GnuPG passphrase to be prompted through the
1806 minibuffer instead of a graphical dialog, depending on whether the gpg
1807 command is called from Emacs (i.e., INSIDE_EMACS environment variable
1808 is set). This feature requires newer versions of GnuPG (2.1.5 or
1809 later) and Pinentry (0.9.5 or later). To use this feature, add
1810 "allow-emacs-pinentry" to "~/.gnupg/gpg-agent.conf" and reload the
1811 configuration with "gpgconf --reload gpg-agent".
1814 ** cl-generic.el provides CLOS-style multiple-dispatch generic functions.
1815 The main entry points are 'cl-defgeneric' and 'cl-defmethod'. See the
1816 node "Generic Functions" in the Emacs Lisp manual for more details.
1819 ** 'scss-mode' (a minor variant of 'css-mode') is a major mode for editing
1820 SCSS (Sassy CSS) files.
1823 ** 'let-alist' is a new macro (and a package) that allows one to easily
1824 let-bind the values stored in an alist.
1827 ** 'tildify-mode' allows automatic insertion of hard spaces as one
1828 types the text. Breaking line after a single-character words is
1829 forbidden by Czech and Polish typography (and may be discouraged in
1830 other languages), so 'auto-tildify-mode' makes it easier to create
1831 a typographically-correct documents.
1834 ** The 'seq' library adds sequence manipulation functions and macros
1835 that complement basic functions provided by subr.el. All functions
1836 are prefixed with 'seq-' and work on lists, strings and vectors.
1837 'pcase' accepts a new Upattern 'seq'.
1840 ** The 'map' library provides map-manipulation functions that work on
1841 alists, hash-table and arrays. All functions are prefixed with
1842 'map-'. 'pcase' accepts a new UPattern 'map'.
1845 ** The 'thunk' library provides functions and macros to control the
1846 evaluation of forms.
1849 ** 'js-jsx-mode' (a minor variant of 'js-mode') provides indentation
1850 support for JSX, an XML-like syntax extension to ECMAScript.
1853 * Incompatible Lisp Changes in Emacs 25.1
1856 ** 'setq' and 'setf' must now be called with an even number of
1857 arguments. The earlier behavior of silently supplying a nil to the
1858 last variable when there was an odd number of arguments has been
1862 ** 'syntax-begin-function' is declared obsolete.
1863 Removed 'font-lock-beginning-of-syntax-function' and the SYNTAX-BEGIN
1864 slot in 'font-lock-defaults'.
1867 ** The new implementation of Subword mode affects word movement everywhere.
1868 When Subword mode is turned on, 'forward-word', 'backward-word', and
1869 everything that uses them will move by sub-words, effectively
1870 overriding the buffer's syntax table. Lisp programs that shouldn't be
1871 affected by Subword mode should call the new functions
1872 'forward-word-strictly' and 'backward-word-strictly' instead.
1875 ** 'package-initialize' now sets 'package-enable-at-startup' to nil if
1876 called during startup. Users who call this function in their init
1877 file and still expect it to be run after startup should set
1878 'package-enable-at-startup' to t after the call to
1879 'package-initialize'.
1882 ** ':global' minor mode use 'setq-default' rather than 'setq'.
1883 This means that you can't use 'make-local-variable' and expect them to
1884 "magically" become buffer-local.
1887 ** 'track-mouse' no longer freezes the shape of the mouse pointer.
1888 The 'track-mouse' form no longer refrains from changing the shape of
1889 the mouse pointer for the entire time the body of that form is
1890 executed. Lisp programs that use 'track-mouse' for dragging across
1891 large portions of the Emacs display, and want to avoid changes in the
1892 pointer shape during dragging, should bind the variable 'track-mouse'
1893 to the special value 'dragging' in the body of the form.
1896 ** The optional PREDICATE argument of 'lisp-complete-symbol' no longer
1897 has any effect. (This change was made in Emacs 24.4 but was not
1898 advertised at the time.)
1901 ** 'indirect-function' does not signal 'void-function' any more.
1902 This is mostly a bug-fix, since this change was missed back in 24.4 when
1903 'symbol-function' was changed not to signal 'void-function' any more.
1906 *** As a consequence, the second arg of 'indirect-function' is now obsolete.
1909 ** 'M-x shell' and 'M-x compile' no longer set the EMACS environment variable.
1910 This avoids clashing when other programs use the variable for other purposes.
1911 Although 'M-x term' still sets EMACS for compatibility with Bash 4.3
1912 and earlier, this is deprecated and will be phased out when Bash 4.4
1913 or later takes over. Use the INSIDE_EMACS environment variable instead.
1916 ** 'save-excursion' does not save&restore the mark any more.
1917 Use 'save-mark-and-excursion' if you want the old behavior.
1920 ** 'read-buffer' and 'read-buffer-function' can now be called with a 4th
1921 argument (PREDICATE).
1924 ** 'completion-table-dynamic' by default stays in the minibuffer.
1925 The minibuffer will be the current buffer when the function is called.
1926 If you want the old behavior of calling the function in the buffer
1927 from which the minibuffer was entered, use the new argument
1928 SWITCH-BUFFER to 'completion-table-dynamic'.
1931 ** window-configurations no longer record the buffers' marks.
1934 ** 'inhibit-modification-hooks' now also inhibits lock-file checks, as
1935 well as active region handling.
1938 ** 'deactivate-mark' is now buffer-local.
1941 ** 'cl-the' now asserts that its argument is of the given type.
1944 ** 'process-running-child-p' may now return a numeric process
1945 group ID instead of t.
1948 ** Mouse click events on mode line or header line no longer include
1949 any reference to a buffer position. The 6th member of the mouse
1950 position list returned for such events is now nil.
1953 ** Menu items in keymaps do not support the "key shortcut cache" any more.
1954 These slots used to hold key-shortcut data, but have been obsolete since
1958 ** Emacs no longer downcases the first letter of a system diagnostic
1959 when signaling a file error. For example, it now reports "Permission
1960 denied" instead of "permission denied". The old behavior was problematic
1961 in languages like German where downcasing rules depend on grammar.
1964 ** New variable 'text-quoting-style' to control how Emacs translates quotes.
1965 Set it to 'curve' for curved single quotes, to 'straight' for straight
1966 apostrophes, and to 'grave' for grave accent and apostrophe. The
1967 default value nil acts like 'curve' if curved single quotes are
1968 displayable, and like 'grave' otherwise. The new variable affects
1969 display of diagnostics and help, but not of info. As the variable is
1970 not intended for casual use, it is not a user option.
1973 ** Message-issuing functions like 'message' and 'error' now translate
1974 various sorts of single quotes in their format strings according to
1975 the value of 'text-quoting-style' (see above). This translation
1976 cannot be disabled. To get the old behavior, use 'format', which is
1977 not affected by 'text-quoting-style', e.g., (message "%s" (format
1981 ** 'substitute-command-keys' now replaces quotes.
1982 That is, it converts documentation strings' quoting style as per the
1983 value of 'text-quoting-style'. Doc strings in source code can use
1984 either curved single quotes or grave accents and apostrophes. As
1985 before, characters preceded by \= are output as-is.
1988 ** The character classes [:alpha:] and [:alnum:] in regular expressions
1989 now match multibyte characters using Unicode character properties.
1990 If you want the old behavior where they matched any character with
1991 word syntax, use '\sw' instead.
1994 ** The character classes [:graph:] and [:print:] in regular expressions
1995 no longer match every multibyte character. Instead, Emacs now
1996 consults the Unicode character properties to determine which
1997 characters are graphic or printable. In particular, surrogates and
1998 unassigned codepoints are now rejected. If you want the old behavior,
1999 use [:multibyte:] instead.
2002 ** The 'diff' command uses the unified format now. To restore the old
2003 behavior, set 'diff-switches' to '-c'.
2006 ** 'grep-template' and 'grep-find-template' values don't include the
2007 --color argument anymore. It's added at the <C> place holder position
2008 dynamically. Any third-party code that changes these templates should
2009 be updated accordingly.
2012 ** '(/ N)' is now equivalent to '(/ 1 N)' rather than to '(/ N 1)'.
2013 The new behavior is compatible with Common Lisp and with XEmacs.
2014 This change does not affect Lisp code intended to be portable to
2015 Emacs 24.2 and earlier, which did not support unary '/'.
2018 ** The 'default-directory' value doesn't have to end slash. To make
2019 that happen, 'unhandled-file-name-directory' now defaults to calling
2020 'file-name-as-directory'.
2023 * Lisp Changes in Emacs 25.1
2027 *** New UPatterns 'quote', 'app'.
2029 *** New UPatterns can be defined with 'pcase-defmacro'.
2031 *** New vector QPattern.
2034 ** 'syntax-propertize' is now automatically called on-demand during forward
2035 parsing functions like 'forward-sexp'.
2038 ** New hooks 'prefix-command-echo-keystrokes-functions' and
2039 'prefix-command-preserve-state-hook' allow the definition of prefix
2040 commands other than the predefined 'C-u'.
2043 ** New functions 'filepos-to-bufferpos' and 'bufferpos-to-filepos'.
2044 These allow conversion between buffer positions and the corresponding
2045 file byte offsets, given the file's encoding.
2048 ** The default value of 'load-read-function' is now 'read'.
2049 Previously, the default value of nil implied using 'read'.
2052 ** New hook 'pre-redisplay-functions'.
2053 It is a bit easier to use than 'pre-redisplay-function'.
2056 ** The second arg of 'looking-back' should always be provided explicitly.
2057 Previously, it was an optional argument, now it's mandatory.
2060 ** Text properties 'intangible', 'point-entered', and 'point-left' are obsolete.
2061 Replaced by properties 'cursor-intangible' and 'cursor-sensor-functions',
2062 implemented by the new 'cursor-intangible-mode' and
2063 'cursor-sensor-mode' minor modes.
2066 ** 'inhibit-point-motion-hooks' now defaults to t and is obsolete.
2067 Use the new minor modes 'cursor-intangible-mode' and
2068 'cursor-sensor-mode' instead.
2071 ** New process type 'pipe', which can be used in combination with the
2072 ':stderr' keyword of 'make-process' to handle standard error output
2076 ** New function 'make-process' provides an alternative interface to
2077 'start-process'. It allows programs to set process parameters such as
2078 process filter, sentinel, etc., through keyword arguments (similar to
2079 'make-network-process').
2082 ** Subprocesses are automatically told about changes in window dimensions.
2083 The new option 'window-adjust-process-window-size-function' controls
2084 how subprocesses are told to adapt their logical window sizes to
2085 changes in the Emacs window configuration. Its default value calls
2086 'set-process-window-size' with the smallest dimensions of all the
2087 windows that display the subprocess's buffer.
2090 ** A new function 'directory-files-recursively' returns all matching
2091 files (recursively) under a directory.
2094 ** New variable 'inhibit-message', when bound to non-nil, inhibits
2095 'message' and related functions from displaying messages in the echo
2096 area. The output is still logged to the '*Messages*' buffer.
2099 ** A new text property 'inhibit-read-only' can be used in read-only
2100 buffers to allow certain parts of the text to be writable.
2103 ** A new variable 'comment-end-can-be-escaped' is useful in languages
2104 such as C and C++ where line comments with escaped newlines are
2105 continued to the next line.
2108 ** New macro 'define-advice'.
2111 ** Emacs Lisp now supports generators.
2112 See the "Generators" section of the ELisp manual for the details.
2115 ** New finalizer facility for running code when objects become unreachable.
2116 See the "Finalizer Type" subsection in the ELisp manual for the
2120 ** Lexical closures can use '(:documentation FORM)' to build their docstring.
2121 It should be placed right where the docstring would be, and FORM is then
2122 evaluated (and should return a string) when the closure is built.
2125 ** 'define-inline' provides a new way to define inlinable functions.
2128 ** New function 'macroexpand-1' to perform a single step of macro expansion.
2131 ** Some "x-*" functions were obsoleted and/or renamed:
2132 *** 'x-select-text' is renamed 'gui-select-text'.
2133 *** 'x-selection-value' is renamed 'gui-selection-value'.
2134 *** 'x-get-selection' is renamed 'gui-get-selection'.
2135 *** 'x-get-clipboard' and 'x-clipboard-yank' are marked obsolete.
2136 *** 'x-get-selection-value' is renamed to 'gui-get-primary-selection'.
2137 *** 'x-set-selection' is renamed to 'gui-set-selection'.
2140 ** New function 'string-greaterp', which return the opposite result of
2144 ** The new functions 'string-collate-lessp' and 'string-collate-equalp'
2145 preserve the collation order as defined by the system's locale(1)
2146 environment. For the time being this is implemented for modern POSIX
2147 systems and for MS-Windows, for other systems they fall back to their
2148 counterparts 'string-lessp' and 'string-equal'.
2151 *** The ls-lisp package uses 'string-collate-lessp' to sort file names.
2152 The effect is that, on systems that use ls-lisp for Dired, the default
2153 sort order of the files in Dired is now different from what it was in
2154 previous versions of Emacs. In particular, the file names are sorted
2155 disregarding punctuation, accents, and diacritics, and letter case is
2156 ignored. For example, files whose name begin with a period will no
2157 longer appear near the beginning of the directory listing. If you
2158 want the old, locale-independent sorting, customize the new option
2159 'ls-lisp-use-string-collate' to the nil value.
2162 *** The MS-Windows specific variable 'w32-collate-ignore-punctuation',
2163 if set to a non-nil value, causes the above 2 functions to ignore
2164 symbol and punctuation characters when collating strings. This
2165 emulates the behavior of modern Posix platforms when the locale's
2166 codeset is "UTF-8" (as in "en_US.UTF-8"). This is needed because
2167 MS-Windows doesn't support UTF-8 as codeset in its locales.
2170 ** New function 'alist-get', which is also a valid place (aka lvalue).
2173 ** New function 'funcall-interactively', which works like 'funcall'
2174 but makes 'called-interactively-p' treat the function as (you guessed it)
2175 called interactively.
2178 ** New function 'function-put' to use instead of 'put' for function properties.
2181 ** The new function 'bidi-find-overridden-directionality' allows you to
2182 find characters whose directionality was, perhaps maliciously,
2183 overridden by directional override control characters. Lisp programs
2184 can use this to detect potential phishing of URLs and other links that
2185 exploits bidirectional display reordering.
2188 ** The new function 'buffer-substring-with-bidi-context' allows you to
2189 copy a portion of a buffer into a different location while preserving
2190 the visual appearance both of the copied text and the text at
2191 destination, even when the copied text includes mixed bidirectional
2192 text and directional control characters.
2195 ** New properties that can be specified with 'declare':
2196 *** '(interactive-only INSTEAD)', says to use INSTEAD for non-interactive use.
2197 *** '(pure VAL)', if VAL is non-nil, indicates the function is pure.
2198 *** '(side-effect-free VAL)', if VAL is non-nil, indicates the function does not
2202 ** New macro 'with-file-modes', for evaluating expressions with default file
2203 permissions set to temporary values (e.g., for creating private files).
2206 ** You can access the slots of structures using 'cl-struct-slot-value'.
2209 ** Function 'sort' can deal with vectors.
2212 ** Function 'system-name' now returns an updated value if the current
2213 system's name has changed or if the Emacs process has changed systems.
2214 To avoid long waits it no longer consults DNS to canonicalize the name
2215 (in some cases this may affect generated message-id headers - customize
2216 'message-user-fqdn' if this bothers you). The variable 'system-name'
2220 ** Function 'write-region' no longer outputs "Wrote FILE" in batch mode.
2223 ** If 'pwd' is called with a prefix argument, insert the current default
2227 ** New functions return extended information about fonts and faces.
2230 *** The function 'font-info' now returns more details about a font.
2231 In particular, it now returns the average width of the font's
2232 characters, which can be used for geometry-related calculations.
2235 *** A new function 'default-font-width' returns the average width of a
2236 character in the current buffer's default font. If the default face
2237 is remapped (see 'face-remapping-alist'), the value for the remapped
2238 face is returned. This function complements the existing function
2239 'default-font-height'.
2242 *** New functions 'window-font-height' and 'window-font-width' return
2243 the height and average width of characters in a specified face and
2244 window. If FACE is remapped (see 'face-remapping-alist'), the
2245 function returns the information for the remapped face.
2248 *** A new function 'window-max-chars-per-line' returns the maximal
2249 number of characters that can be displayed on one line. If a face
2250 and/or window are provided, these values are used for the
2251 calculation. This function is different from 'window-body-width' in
2252 that it accounts for (i) continuation glyphs, (ii) the size of the
2253 font, and (iii) the specified window.
2256 ** New utilities in subr-x.el:
2258 *** New macros 'if-let' and 'when-let' allow defining bindings and to
2259 execute code depending whether all values are true.
2261 *** New macros 'thread-first' and 'thread-last' allow threading a form
2262 as the first or last argument of subsequent forms.
2265 ** Documentation strings now support quoting with curved single quotes
2266 in addition to the old style with grave accent and apostrophe. The
2267 new style looks better on today's displays. In the new Electric Quote
2268 mode, you can enter curved single quotes into documentation by typing
2269 grave accent and apostrophe. Outside Electric Quote mode, you can
2270 enter them by typing 'C-x 8 [' and 'C-x 8 ]', or (if your Alt key
2271 works) by typing 'A-[' and 'A-]'. As described above under
2272 'text-quoting-style', the user can specify how to display doc string
2276 ** New function 'format-message' is like 'format' and also converts
2277 curved single quotes, grave accents and apostrophes as per
2278 'text-quoting-style'.
2281 ** 'show-help-function's arg is converted via 'substitute-command-keys'
2282 before being passed to the function. Help strings, help-echo
2283 properties, etc. can therefore contain command key escapes and
2287 ** Time-related changes:
2289 *** Time conversion functions now accept an optional ZONE argument
2290 that specifies the time zone rules for conversion. ZONE is omitted or
2291 nil for Emacs local time, t for Universal Time, 'wall' for system wall
2292 clock time, or a string as in the TZ environment variable. The
2293 affected functions are 'current-time-string', 'current-time-zone',
2294 'decode-time', and 'format-time-string'. The function 'encode-time',
2295 which already accepted a simple time zone rule argument, has been
2296 extended to accept all the new forms.
2298 *** Incompatible change in the third argument of 'format-time-string'.
2299 Previously, any non-nil argument was interpreted as specifying Universal Time.
2300 This is no longer true; packages that want Universal Time should pass t
2301 as the third argument.
2303 *** Time-related functions now consistently accept numbers
2304 (representing seconds since the epoch) and nil (representing the
2305 current time) as well as the usual list-of-integer representation.
2306 Affected functions include 'current-time-string', 'current-time-zone',
2307 'decode-time', 'float-time', 'format-time-string', 'seconds-to-time',
2308 'time-add', 'time-less-p', 'time-subtract', 'time-to-day-in-year',
2309 'time-to-days', and 'time-to-seconds'.
2311 *** The 'encode-time-value' and 'with-decoded-time-value' macros have
2314 *** 'calendar-next-time-zone-transition', 'time-add', and
2315 'time-subtract' no longer return time values in the obsolete and
2316 undocumented integer-pair format. Instead, they return a list of two
2320 ** New function 'set-binary-mode' allows switching a standard stream
2321 of the Emacs process to binary I/O mode.
2324 ** The new function 'directory-name-p' can be used to check whether a file
2325 name (as returned from, for instance, 'file-name-all-completions') is
2326 a directory file name. It returns non-nil if the last character in
2327 the name is a directory separator character (forward slash on GNU and
2328 Unix systems, forward- or backslash on MS-Windows and MS-DOS).
2331 ** ASCII approximations to curved quotes are put in 'standard-display-table'
2332 if the terminal cannot display curved quotes.
2335 ** Standard output and error streams now transliterate characters via
2336 'standard-display-table', and encode output using 'locale-coding-system'.
2337 To force a specific encoding, bind 'coding-system-for-write' to the
2338 coding-system of your choice when invoking functions like 'prin1' and
2342 ** New var 'truncate-string-ellipsis' to choose how to indicate truncation.
2345 ** New possible value for 'system-type': 'nacl'.
2346 This is used by Google's Native Client (NaCl).
2348 ** Miscellaneous name change
2351 For consistency with the usual Emacs spelling, the Lisp variable
2352 'hfy-optimisations' has been renamed to 'hfy-optimizations'.
2353 The old name should still work, as an obsolescent alias.
2355 ** Changes in Frame- and Window- Handling
2358 *** Emacs can now draw horizontal scroll bars on some platforms that
2359 provide toolkit scroll bars, namely Gtk+, Lucid, Motif and Windows.
2360 Horizontal scroll bars are turned off by default.
2362 **** New function 'horizontal-scroll-bars-available-p' telling whether
2363 horizontal scroll bars are available on the underlying system.
2365 **** New mode 'horizontal-scroll-bar-mode' to toggle horizontal scroll
2366 bars on all existing and future frames.
2368 **** New function 'toggle-horizontal-scroll-bar' to toggle horizontal
2369 scroll bars on the selected frame.
2371 **** New frame parameters 'horizontal-scroll-bars' and
2372 'scroll-bar-height' to set horizontal scroll bars and their height
2373 for individual frames and in 'default-frame-alist'.
2375 **** New functions 'frame-scroll-bar-height' and
2376 'window-scroll-bar-height' return the height of horizontal scroll
2377 bars on a specific frame or window.
2379 **** 'set-window-scroll-bars' now accepts five parameters where the last
2380 two specify height and type of the window's horizontal scroll bar.
2382 **** 'window-scroll-bars' now returns type and sizes of horizontal scroll
2385 **** New buffer-local variables 'horizontal-scroll-bar' and
2386 'scroll-bar-height'.
2389 *** New functions 'frame-geometry' and 'frame-edges' give access to a
2393 *** New functions 'mouse-absolute-pixel-position' and
2394 'set-mouse-absolute-pixel-position' get/set screen coordinates of the
2398 *** The function 'window-edges' now accepts three additional arguments to
2399 retrieve body, absolute and pixel edges of the window.
2402 *** The functions 'window-inside-edges', 'window-inside-pixel-edges' and
2403 'window-inside-absolute-pixel-edges' have been renamed to respectively
2404 'window-body-edges', 'window-body-pixel-edges' and
2405 'window-absolute-body-pixel-edges'. The old names are kept as aliases.
2408 *** New function 'window-absolute-pixel-position' to get the screen
2409 coordinates of a visible buffer position.
2412 *** The height of a frame's menu and tool bar are no longer counted in the
2413 frame's text height. This means that the text height stands only for
2414 the height of the frame's root window plus that of the echo area (if
2415 present). This was already the behavior for frames with external tool
2416 and menu bars (like in the Gtk builds) but has now been extended to all
2420 *** Frames now do not necessarily preserve the number of columns or lines
2421 they display when setting default font, menu bar, fringe width, or
2422 scroll bars. In particular, maximized and fullscreen frames are
2423 conceptually never resized if such settings change. For fullheight and
2424 fullwidth frames, the behavior may depend on the toolkit used.
2426 **** New option 'frame-inhibit-implied-resize' if non-nil, means that
2427 setting default font, menu bar, fringe width, or scroll bars of a
2428 specific frame does not resize that frame in order to preserve the
2429 number of columns or lines it displays.
2432 *** New function 'window-preserve-size' allows you to preserve the size of
2433 a window without "fixing" it. It's supported by 'fit-window-to-buffer',
2434 'temp-buffer-resize-mode' and 'display-buffer'.
2437 *** New 'display-buffer' action function 'display-buffer-use-some-frame'.
2438 This displays the buffer in an existing frame other than the current
2439 frame, and allows the caller to specify a frame predicate to exclude
2443 *** New minor mode 'window-divider-mode' and options
2444 'window-divider-default-places', 'window-divider-default-bottom-width'
2445 and 'window-divider-default-right-width'.
2448 *** The window displaying the '*Completions*' buffer with minibuffer
2449 completion candidates is now shown at the bottom of the selected
2450 frame. The size of that window is always as large as required to
2451 display all the candidates, except when limited by the minimum size
2452 of the other windows on that frame; those other windows are resized
2453 to provide space for the '*Completions*' display. The Emacs manual
2454 describes how to customize 'display-buffer-alist' to get back the old
2455 behavior, see the node "Temporary Displays" there.
2458 ** Tearoff menus and detachable toolbars for Gtk+ have been removed.
2459 Those features have been deprecated in Gtk+ for a long time.
2464 *** etags no longer qualifies class members by default.
2466 By default, 'etags' will not qualify class members for Perl and C-like
2467 object-oriented languages with their class names and namespaces, and
2468 will remove qualifications used explicitly in the code from the tag
2469 names it puts in TAGS files. This is so the etags.el back-end for
2470 'xref-find-definitions' is more accurate and produces less false
2473 Use --class-qualify (-Q) if you want the old default behavior of
2474 qualifying class members in C++, Java, Objective C, and Perl. Note
2475 that using -Q might make some class members become "unknown" to 'M-.'
2476 ('xref-find-definitions'); if so, you can use 'C-u M-.' to specify the
2477 qualified names by hand.
2480 *** New language Ruby
2482 Names of modules, classes, methods, functions, and constants are
2483 tagged. Overloaded operators are also tagged.
2487 Names of packages, functions, and types are tagged.
2490 *** Improved support for Lua
2492 Etags now tags functions even if the "function" keyword follows some
2493 whitespace at line beginning.
2496 * Changes in Emacs 25.1 on Non-Free Operating Systems
2499 ** MS-Windows specific Emacs build scripts are no longer in the distribution.
2500 This includes the makefile.w32-in files in various subdirectories, and
2501 the support files. The file nt/configure.bat now just tells the user
2502 to use the procedure described in nt/INSTALL, by running the Posix
2503 'configure' script in the top-level directory.
2506 ** Building Emacs for MS-Windows requires at least Windows XP
2507 or Windows Server 2003. The built binaries still run on all versions
2508 of Windows starting with Windows 9X.
2511 ** Emacs running on MS-Windows now supports the daemon mode.
2514 ** The byte counts in etags-generated TAGS files are now the same on
2515 MS-Windows as they are on other platforms.
2518 ** On OS X, configure creates a Cocoa ("Nextstep") build by default.
2519 Pass '--without-ns' to configure to create an X11 build, the old default.
2522 ** OS X 10.5 or older is no longer supported.
2525 ** OS X on PowerPC is no longer supported.
2528 ** New variable 'ns-use-fullscreen-animation' controls animation for
2529 non-native NS fullscreen. The default is nil. Set to t to enable
2530 animation when entering and leaving fullscreen. For native OSX fullscreen
2533 ** On the OS X Cocoa ("Nextstep") port, multicolor font (such as color
2534 emoji) display is disabled. This feature was accidentally added when
2535 Emacs 24.4 included the new Core Text based font backend code that was
2536 originally implemented for a non-mainline port. This will be enabled
2537 again once it is also implemented in Emacs on free operating systems.
2538 If some symbols, such as emoji, do not display, we suggest to install
2539 an appropriate font, such as Symbola; then they will be displayed,
2540 albeit without the color effects.
2543 ** The new function 'w32-application-type' returns the type of an
2544 MS-Windows application given the name of its executable program file.
2546 ** New variable 'w32-pipe-buffer-size'.
2547 It can be used to tune the size of the buffer of pipes created for
2548 communicating with subprocesses, when the program run by a subprocess
2549 exhibits unusual buffering behavior. Default is zero, which lets the
2550 OS use its default size.
2553 ----------------------------------------------------------------------
2554 This file is part of GNU Emacs.
2556 GNU Emacs is free software: you can redistribute it and/or modify
2557 it under the terms of the GNU General Public License as published by
2558 the Free Software Foundation, either version 3 of the License, or
2559 (at your option) any later version.
2561 GNU Emacs is distributed in the hope that it will be useful,
2562 but WITHOUT ANY WARRANTY; without even the implied warranty of
2563 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
2564 GNU General Public License for more details.
2566 You should have received a copy of the GNU General Public License
2567 along with GNU Emacs. If not, see <http://www.gnu.org/licenses/>.
2573 paragraph-separate: "[
\f]*$"