NEWS

GNU Emacs NEWS -- history of user-visible changes.

Copyright (C) 2010-2012 Free Software Foundation, Inc.
See the end of the file for license conditions.

Please send Emacs bug reports to bug-gnu-emacs@gnu.org.
If possible, use M-x report-emacs-bug.

This file is about changes in Emacs version 24.

See files NEWS.23, NEWS.22, NEWS.21, NEWS.20, NEWS.19, NEWS.18,
and NEWS.1-17 for changes in older Emacs versions.

You can narrow news to a specific version by calling `view-emacs-news'
with a prefix argument or by typing C-u C-h C-n.

* Installation Changes in Emacs 24.3

** The default toolkit has been changed to Gtk+ version 3.
If you don't pass `--with-x-toolkit' to configure, or if you use
`--with-x-toolkit=gtk' or `--with-x-toolkit=yes', configure will try
to build with Gtk+ version 3, and if that fails, try Gtk+ version 2.
You can explicitly require a specific version by passing
`--with-x-toolkit=gtk2' or `--with-x-toolkit=gtk3' to configure.

** New configure option `--without-all' to disable additional features.
This disables most of the features that are normally enabled by default.

** New configure option `--enable-link-time-optimization' to utilize
an appropriate feature provided by GCC since version 4.5.0.

** New configure option `--enable-gcc-warnings', intended for developers.
If building with GCC, this enables compile-time checks that warn about
possibly-questionable C code.  On a recent GNU system there should be
no warnings; on older and on non-GNU systems the generated warnings
may be useful.

** The configure option `--enable-use-lisp-union-type' has been
renamed to '--enable-check-lisp-object-type', as the resulting
Lisp_Object type no longer uses a union to implement the compile time
check that this option enables.

** The configure option `--disable-maintainer-mode' has been removed,
as it was confusingly-named and rarely useful.

** The configure options `--program-prefix', `--program-suffix', and
`--program-transform-name' apply to more than just the installed
binaries.  Now they also affect the man pages, icons, and the
etc/emacs.desktop file; but not the info pages, since this would break
links between the various manuals.

** You can use `NO_BIN_LINK=t make install' to prevent the installation
overwriting "emacs" in the installation bin/ directory with a link
to emacs-VERSION.

** Emacs uses libtinfo in preference to libncurses, if available.

** On FreeBSD and NetBSD, configure no longer adds /usr/local/lib and
/usr/pkg/lib to the linker search path.  You must add them yourself if
you want them.

** The standalone scripts rcs-checkin and vcdiff have been removed
(from the bin and libexec directories, respectively).  The former is
no longer relevant, the latter is replaced by lisp (in vc-sccs.el).


* Startup Changes in Emacs 24.3

** Emacs no longer searches for `leim-list.el' files beneath the standard
lisp/ directory.  There should not be any there anyway.  If you have
been adding them there, put them somewhere else; e.g., site-lisp.

** The `--no-site-lisp' command line option now works for Nextstep builds.


* Changes in Emacs 24.3

** Most `y-or-n' prompts now allow you to scroll the selected window.
Typing `C-v' or `M-v' at a y-or-n prompt scrolls forward or backward
respectively, without exiting from the prompt.

** Mode line changes

*** New option `mode-line-default-help-echo' specifies the help text
(shown in a tooltip or in the echo area) for any part of the mode line
that does not have its own specialized help text.

*** You can now click mouse-3 in the coding system indicator to invoke
`set-buffer-file-coding-system'.

** Help changes

*** `C-h f' (describe-function) can now perform autoloading.
When this command is called for an autoloaded function whose docstring
contains a key substitution construct, that function's library is
automatically loaded, so that the documentation can be shown
correctly.  To disable this, set `help-enable-auto-load' to nil.

*** `C-h f' now reports previously-autoloaded functions as "autoloaded",
even after their associated libraries have been loaded (and the
autoloads have been redefined as functions).

** Minibuffer changes

*** In minibuffer filename prompts, `C-M-f' and `C-M-b' now move to the
next and previous path separator, respectively.

*** `minibuffer-electric-default-mode' can shorten "(default ...)" to "[...]"
in minibuffer prompts.  Just set `minibuffer-eldef-shorten-default'
non-nil before enabling the mode.

** ImageMagick support, if available, is automatically enabled.
It is no longer necessary to call `imagemagick-register-types'
explicitly to install ImageMagick image types; that function is called
automatically at startup, or when customizing an imagemagick- option.

*** Setting `imagemagick-types-inhibit' to t now disables the use of
ImageMagick to view images.  (You must call `imagemagick-register-types'
afterwards if you do not use customize to change this.)

*** The new variable `imagemagick-enabled-types' also affects which
ImageMagick types are treated as images.  The function
`imagemagick-filter-types' returns the list of types that will be
treated as images.

*** Images displayed via ImageMagick now support transparency and the
:background image specification property.

** Server and client changes

*** emacsclient now obeys string values for `initial-buffer-choice',
if it is told to open a new frame without specifying any file to visit
or expression to evaluate.

*** New option `server-auth-key' specifies a shared server key.

** In the Package Menu, newly-available packages are listed as "new",
and sorted above the other "available" packages by default.

** `C-x C-q' is now bound to the new minor mode `read-only-mode'.
This minor mode replaces `toggle-read-only', which is now obsolete.

** Emacs now generates backtraces on fatal errors.
On encountering a fatal error, Emacs now outputs a textual description
of the fatal signal, and a short backtrace on platforms like glibc
that support backtraces.

** If your Emacs was built from a bzr checkout, the new variable
`emacs-bzr-version' contains information about the bzr revision used.

** New variable `create-lockfiles' specifies usage of lockfiles.
It defaults to t.  Changing it to nil inhibits the creation of lock
files (use this with caution).

** Using "unibyte: t" in Lisp source files is obsolete.
Use "coding: raw-text" instead.

** Setting `enable-remote-dir-locals' to non-nil allows directory
local variables on remote hosts.

** The entry for PCL-CVS has been removed from the Tools menu.
The PCL-CVS commands are still available via the keyboard.

** Internationalization changes

*** New language environment: Persian.

*** New input method `vietnamese-vni'.

** Nextstep (GNUstep / Mac OS X) port changes

*** Support for fullscreen and the frame parameter fullscreen.

*** A file dialog is used for open/save operations initiated from the
menu/toolbar.


* Editing Changes in Emacs 24.3

** Navigation command changes

*** New binding `M-g c' for `goto-char'.

*** New binding `M-g TAB' for `move-to-column'.

*** `M-g TAB' (`move-to-column') prompts for a column number if called
interactively with no prefix arg.  Previously, it moved to column 1.

** Search and Replace changes

*** Non-regexp Isearch now performs "lax" space matching.
Each sequence of spaces in the supplied search string may match any
sequence of one or more whitespace characters, as specified by the
variable `search-whitespace-regexp'.  (This variable is also used by a
similar existing feature for regexp Isearch.)

*** New Isearch command `M-s SPC' toggles lax space matching.
This applies to both ordinary and regexp Isearch.

*** New option `replace-lax-whitespace'.
If non-nil, `query-replace' uses flexible whitespace matching too.
The default is nil.

*** Global `M-s _' starts a symbol (identifier) incremental search,
and `M-s _' in Isearch toggles symbol search mode.
`M-s c' in Isearch toggles search case-sensitivity.

** `C-x 8 RET' is now bound to `insert-char', which is now a command.
`ucs-insert' is now an obsolete alias for `insert-char'.

** The `z' key no longer has a binding in most special modes.
It used to be bound to `kill-this-buffer', but `z' is too easy to
accidentally type.

** New option `delete-trailing-lines' specifies whether
M-x delete-trailing-whitespace should delete trailing lines at the end
of the buffer.  It defaults to t.

** Register changes

*** `C-x r +' is now overloaded to invoke `append-to-register'.

*** New option `register-separator' specifies the register containing
the text to put between collected texts for use with
M-x append-to-register and M-x prepend-to-register.

** `C-u M-=' now counts lines/words/characters in the entire buffer.

** New command `C-x r M-w' (`copy-rectangle-as-kill').
It copies the region-rectangle as the last rectangle kill.

** New option `yank-handled-properties' allows processing of text
properties on yanked text, in ways that are more general than just
removing them, as done by `yank-excluded-properties'.


* Changes in Specialized Modes and Packages in Emacs 24.3

** Apropos

*** The faces used by Apropos are now directly customizable.
These faces are named `apropos-symbol', `apropos-keybinding', and so on;
see the `apropos' Custom group for details.

*** The old options whose values specified faces to use have been removed
(i.e. `apropos-symbol-face', `apropos-keybinding-face', etc.).

** Buffer Menu

*** This package has been rewritten to use Tabulated List mode.

*** Option `Buffer-menu-buffer+size-width' is now obsolete.
Use `Buffer-menu-name-width' and `Buffer-menu-size-width' instead.

** Calendar

*** You can customize the header text that appears above each calendar month.
See the variable `calendar-month-header'.

*** New LaTeX calendar style, produced by `cal-tex-cursor-week2-summary'.

*** The calendars produced by cal-html include holidays.
Customize `cal-html-holidays' to change this.

** CL

*** CL's main entry is now (require 'cl-lib).
`cl-lib' is like the old `cl' except that it uses the namespace cleanly;
i.e., all its definitions have the "cl-" prefix (and internal definitions
use the "cl--" prefix).

If `cl' provided a feature under the name `foo', then `cl-lib'
provides it under the name `cl-foo' instead; with the exceptions of the
few `cl' definitions that had to use `foo*' to avoid conflicts with
pre-existing Elisp entities.  These have been renamed to `cl-foo'
rather than `cl-foo*'.

The old `cl' is now deprecated and is mainly just a bunch of aliases that
provide the old, non-prefixed names.  Some exceptions are listed below:

*** `cl-flet' is not like `flet' (which is deprecated).
Instead it obeys the behavior of Common-Lisp's `flet'.
In particular, in cl-flet function definitions are lexically scoped,
whereas in flet the scoping is dynamic.

*** `cl-labels' is slightly different from `labels'.
The difference is that it relies on the `lexical-binding' machinery
(as opposed to the `lexical-let' machinery used previously) to capture
definitions in closures, so such closures will only work if `lexical-binding'
is in use.

*** `cl-letf' is not exactly like `letf'.
The only difference is in details that relate to some deprecated usage
of `symbol-function' in place forms.

*** `progv' was rewritten to use the `let' machinery.
A side effect is that variables without corresponding values are bound
to nil rather than being made unbound.

*** The following methods of extending `setf' are obsolete
(use features from gv.el instead):
`define-modify-macro' (use `gv-letplace')
`defsetf' (use `gv-define-simple-setter' or `gv-define-setter')
`define-setf-expander' (use `gv-define-setter' or `gv-define-expander')
`get-setf-method' no longer exists (see "Incompatible Lisp Changes")

** New compilation option `compilation-always-kill'.

** Customize

*** `custom-reset-button-menu' now defaults to t.

*** Non-option variables are never matched in `customize-apropos' and
`customize-apropos-options' (i.e., the prefix argument does nothing for
these commands now).

** `desktop-path' no longer includes the "." directory.
Desktop files are now located in ~/.emacs.d by default.

** D-Bus

*** New variables `dbus-compiled-version' and `dbus-runtime-version'.

*** The D-Bus object manager interface is implemented.

*** Variables of type :(u)int32 and :(u)int64 accept floating points,
if their value does not fit into Emacs's integer range.

*** The function `dbus-call-method' is now non-blocking.
It can be interrupted by `C-g'.  `dbus-call-method-non-blocking' is obsolete.

*** Signals can also be sent as unicast messages.

*** The argument list of `dbus-register-signal' has been extended,
according to the new match rule types of D-Bus.  See the manual for details.

*** `dbus-init-bus' supports private connections.

*** There is a new function `dbus-setenv'.

** Diff mode

*** Changes are now highlighted using the same color scheme as in
modern VCSes.  Deletions are displayed in red (new faces
`diff-refine-removed' and `smerge-refined-removed', and new definition
of `diff-removed'), insertions in green (new faces `diff-refine-added'
and `smerge-refined-added', and new definition of `diff-added').

*** The variable `diff-use-changed-face' defines whether to use the
face `diff-changed', or `diff-removed' and `diff-added' to highlight
changes in context diffs.

*** The new command `diff-delete-trailing-whitespace' removes trailing
whitespace introduced by a diff.

** Dired

*** `dired-do-async-shell-command' executes each file sequentially
if the command ends in `;' (when operating on multiple files).
Otherwise, it executes the command on each file in parallel.

*** Typing `M-n' in the minibuffer of `dired-do-chmod', `dired-do-chgrp',
`dired-do-chown', and `dired-do-touch' yanks the attributes of the
file at point.

*** When the region is active, `m' (`dired-mark'), `u' (`dired-unmark'),
`DEL' (`dired-unmark-backward'), and `d' (`dired-flag-file-deletion')
mark/unmark/flag all files in the active region.

*** The minibuffer default for `=' (`dired-diff) has changed.
It is now the backup file for the file at point, if one exists.
In Transient Mark mode the default is the file at the active mark.

*** `M-=' is no longer bound to `dired-backup-diff' in Dired buffers.
The global binding for `M-=', `count-words-region' is in effect.

** Ediff now uses the same color scheme as Diff mode.

** ERC

*** New module "notifications", which can send a notification when you
receive a private message or your nickname is mentioned.

*** ERC will look up server/channel names via auth-source and use any
channel keys found.

*** New option `erc-lurker-hide-list', similar to `erc-hide-list', but
only applies to messages sent by lurkers.

** Flymake uses fringe bitmaps to indicate errors and warnings.
See `flymake-fringe-indicator-position', `flymake-error-bitmap' and
`flymake-warning-bitmap'.

** Follow mode no longer works by using advice.
The option `follow-intercept-processes' has been removed.

** The FFAP option `ffap-url-unwrap-remote' can now be a list of strings,
specifying URL types that should be converted to remote file names at
the FFAP prompt.  The default is now '("ftp").

** New Ibuffer `derived-mode' filter, bound to `/ M'.
The old binding for `/ M' (filter by used-mode) is now bound to `/ m'.

** `javascript-generic-mode' is now an obsolete alias for `js-mode'.

** New option `mouse-avoidance-banish-position' specifies where the
`banish' mouse avoidance setting moves the mouse.

** notifications.el supports now version 1.2 of the Notifications API.
The function `notifications-get-capabilities' returns the supported
server properties.

** In Perl mode, new option `perl-indent-parens-as-block' causes non-block
closing brackets to be aligned with the line of the opening bracket.

** In Proced mode, new command `proced-renice' renices marked processes.

** Python mode

A new version of python.el, which provides several new features, including:
per-buffer shells, better indentation, Python 3 support, and improved
shell-interaction compatible with iPython (and virtually any other
text based shell).

*** Some user options have been replaced/renamed, including:
Old defcustom:                | New defcustom:
python-indent                 | python-indent-offset
python-guess-indent           | python-indent-guess-indent-offset
python-pdbtrack-do-tracking-p | python-pdbtrack-activate
python-use-skeletons          | python-skeleton-autoinsert

*** Some user options have been removed, including:

**** `python-indent-string-contents': Strings are never indented.

**** `python-honour-comment-indentation':
Comments are never considered as indentation markers themselves.

**** `python-continuation-offset': Indentation is automatically
calculated in a pep8 compliant way depending on the context.

**** `python-shell-prompt-alist', `python-shell-continuation-prompt-alist':
Have no direct mapping as the shell interaction is completely different.

**** `python-python-command', `python-jython-command':
Replaced by `python-shell-interpreter'.

**** `inferior-python-filter-regexp', `python-remove-cwd-from-path',
`python-pdbtrack-minor-mode-string', `python-source-modes':
No longer relevant.

*** Some commands have been replaced:
Old command               | New command
python-insert-class       | python-skeleton-class
python-insert-def         | python-skeleton-def
python-insert-for         | python-skeleton-for
python-insert-if          | python-skeleton-if
python-insert-try/except  | python-skeleton-try
python-insert-try/finally | python-skeleton-try
python-insert-while       | python-skeleton-while
python-find-function      | python-nav-jump-to-defun
python-next-statement     | python-nav-forward-sentence
python-previous-statement | python-nav-backward-sentence
python-beginning-of-defun-function  | python-nav-beginning-of-defun
python-end-of-defun-function        | python-nav-end-of-defun
python-send-buffer        | python-shell-send-buffer
python-send-defun         | python-shell-send-defun
python-send-region        | python-shell-send-region
python-send-region-and-go | Emulate with python-shell-send-region and
                            python-shell-switch-to-shell
python-send-string        | python-shell-send-string
python-switch-to-python   | python-shell-switch-to-shell
python-describe-symbol    | python-eldoc-at-point

** reStructuredText mode

*** Keybindings (see `C-c C-h'), TAB indentation, filling and auto-filling,
fontification, comment handling, and customization have all been revised
and improved.

*** Support for `imenu' and `which-function-mode'.

*** The reStructuredText syntax is more closely covered.
Sphinx support has been improved.

*** `rst-insert-list' inserts new list or continues existing lists.

*** A negative prefix argument always works for `rst-adjust'.

*** The window configuration is reset after displaying a TOC.

*** The constant `rst-version' describes the rst.el package version.

** Shell Script mode

*** Pairing of parens/quotes uses `electric-pair-mode' instead of skeleton-pair.

*** `sh-electric-here-document-mode' now controls auto-insertion of here-docs.

*** `sh-use-smie' lets you choose a new indentation and navigation code.

** New option `async-shell-command-buffer' specifies the buffer to use
for a new asynchronous `shell-command' when the default output buffer
`*Async Shell Command*' is already in use.

** SQL mode has a new option `sql-db2-escape-newlines'.
If non-nil, newlines sent to the command interpreter will be escaped
by a backslash.  The default does not escape the newlines and assumes
that the sql statement will be terminated by a semicolon.

** New command `tabulated-list-sort', bound to `S' in Tabulated List mode
(and modes that derive from it), sorts the column at point, or the Nth
column if a numeric prefix argument is given.

** Term

*** The variables `term-default-fg-color' and `term-default-bg-color'
are now deprecated in favor of the customizable face `term'.

*** You can customize how to display ANSI terminal colors and styles
by customizing the corresponding `term-color-<COLOR>',
`term-color-underline' and `term-color-bold' faces.

** Tramp

*** The syntax has been extended in order to allow ad-hoc proxy definitions.
See the manual for details.

*** Remote processes are now also supported on remote MS-Windows hosts.

** URL

*** Structs made by `url-generic-parse-url' have nil `attributes' slot.
Previously, this slot stored semicolon-separated attribute-value pairs
appended to some imap URLs, but this is not compatible with RFC 3986.
So now the `filename' slot stores the entire path and query components,
and the `attributes' slot is always nil.

*** New function `url-encode-url' for encoding a URI string.
The `url-retrieve' function now uses this to encode its URL argument,
in case that is not properly encoded.

** VHDL mode

*** The free software compiler GHDL is supported (and now the default).

*** Support for the VHDL-AMS packages has been added/updated.

*** Updated to the 2002 revision of the VHDL standard.

*** Accepts \r and \f as whitespace.

** `which-func-modes' now defaults to t, so Which Function mode, when
enabled, applies to all applicable major modes.

** winner-mode-hook now runs when the mode is disabled, as well as when
it is enabled.

** Hooks renamed to avoid obsolete "-hooks" suffix:
*** semantic-lex-reset-hooks -> semantic-lex-reset-functions
*** semantic-change-hooks -> semantic-change-functions
*** semantic-edits-new-change-hooks -> semantic-edits-new-change-functions
*** semantic-edits-delete-change-hooks -> semantic-edits-delete-change-functions
*** semantic-edits-reparse-change-hooks -> semantic-edits-reparse-change-functions
*** semanticdb-save-database-hooks -> semanticdb-save-database-functions
*** c-prepare-bug-report-hooks -> c-prepare-bug-report-hook
*** rcirc-sentinel-hooks -> rcirc-sentinel-functions
*** rcirc-receive-message-hooks -> rcirc-receive-message-functions
*** rcirc-activity-hooks -> rcirc-activity-functions
*** rcirc-print-hooks -> rcirc-print-functions
*** dbus-event-error-hooks -> dbus-event-error-functions
*** eieio-pre-method-execution-hooks -> eieio-pre-method-execution-functions
*** checkdoc-style-hooks -> checkdoc-style-functions
*** checkdoc-comment-style-hooks -> checkdoc-comment-style-functions
*** archive-extract-hooks -> archive-extract-hook
*** filesets-cache-fill-content-hooks -> filesets-cache-fill-content-hook
*** hfy-post-html-hooks -> hfy-post-html-hook
*** nndiary-request-create-group-hooks -> nndiary-request-create-group-functions
*** nndiary-request-update-info-hooks -> nndiary-request-update-info-functions
*** nndiary-request-accept-article-hooks -> nndiary-request-accept-article-functions
*** gnus-subscribe-newsgroup-hooks -> gnus-subscribe-newsgroup-functions

** Obsolete packages:

*** assoc.el
In most cases, assoc+member+push+delq work just as well.
And in any case it's just a terrible package: ugly semantics, terrible
inefficiency, and not namespace-clean.

*** bruce.el

*** cust-print.el

*** ledit.el

*** mailpost.el

*** mouse-sel.el

*** patcomp.el


* Incompatible Lisp Changes in Emacs 24.3

** set-buffer-multibyte now signals an error in narrowed buffers.

** `random' by default now returns a different random sequence in
every Emacs run.  Use `(random S)', where S is a string, to set the
random seed to a value based on S, in order to get a repeatable
sequence in later calls.

** The function `x-select-font' can return a font spec, instead of a
font name as a string.  Whether it returns a font spec or a font name
depends on the graphical library.

** If the NEWTEXT arg to `replace-match' contains a substring "\?",
that substring is inserted literally even if the LITERAL arg is
non-nil, instead of causing an error to be signaled.

** `select-window' now always makes the window's buffer current.
It does so even if the window was selected before.

** Docstrings starting with `*' no longer indicate user options.
Only variables defined using `defcustom' are considered user options.
The function `user-variable-p' is now an obsolete alias for
`custom-variable-p'.

** The return values of `defalias', `defun' and `defmacro' have changed,
and are now undefined.  For backwards compatibility, `defun' and
`defmacro' currently return the name of the newly defined
function/macro, but this should not be relied upon.

** `face-spec-set' no longer sets frame-specific attributes when the
third argument is a frame (that usage was obsolete since Emacs 22.2).

** The arguments of `dbus-register-signal' are no longer just strings,
but keywords or keyword-string pairs.  The old argument list will
still be supported for Emacs 24.x.

** The CL package's `get-setf-method' function no longer exists.
Generalized variables are now part of core Emacs Lisp, and implemented
differently to the way cl.el used to do it.  It is not possible to
define a compatible replacement for `get-setf-method'.  See the file
gv.el for internal details of the new implementation.

** Spelling changes.
Some Lisp symbols have been renamed to correct their spelling,
or to be more consistent with standard Emacs terminology.

*** Renamed functions
**** hangul-input-method-inactivate -> hangul-input-method-deactivate
**** inactivate-input-method -> deactivate-input-method
**** quail-inactivate -> quail-deactivate
**** robin-inactivate -> robin-deactivate
**** viper-inactivate-input-method -> viper-deactivate-input-method
**** viper-inactivate-input-method-action ->
     viper-deactivate-input-method-action
**** ucs-input-inactivate -> ucs-input-deactivate

*** Renamed hooks
The old hooks are still supported for backward compatibility, but they
are deprecated and will be removed eventually.
**** input-method-inactivate-hook -> input-method-deactivate-hook
**** robin-inactivate-hook -> robin-deactivate-hook
**** quail-inactivate-hook -> quail-deactivate-hook

*** Renamed Lisp variables
**** follow-deactive-menu -> follow-inactive-menu
**** inactivate-current-input-method-function ->
     deactivate-current-input-method-function

** Some obsolete functions, variables, and faces have been removed:
*** `last-input-char', `last-command-char', `unread-command-char'
*** `facemenu-unlisted-faces'
*** `rmail-decode-mime-charset'
*** `iswitchb-read-buffer'
*** `sc-version', `sc-submit-bug-report'
*** `set-char-table-default'
*** `string-to-sequence' (use `string-to-list' or `string-to-vector')
*** `compile-internal'
*** `modeline'
*** `mode-line-inverse-video'
*** `follow-mode-off-hook'
*** `cvs-commit-buffer-require-final-newline'
(use `log-edit-require-final-newline' instead)
*** `cvs-changelog-full-paragraphs'
(use `log-edit-changelog-full-paragraphs' instead)
*** `cvs-diff-ignore-marks', `cvs-diff-buffer-name'
*** `vc-ignore-vc-files' (use `vc-handled-backends' instead)
*** `vc-master-templates' (use `vc-handled-backends' instead)
*** `vc-checkout-carefully'


* Lisp changes in Emacs 24.3

** New sampling-based Elisp profiler.
Try M-x profiler-start, do some work, and then call M-x profiler-report.
When finished, use M-x profiler-stop.  The sampling rate can be based on
CPU time or memory allocations.

** CL-style generalized variables are now in core Elisp.
`setf' is autoloaded; `push' and `pop' accept generalized variables.
You can define your own generalized variables using `gv-define-simple-setter',
`gv-define-setter', etc.

** `defun' also accepts a (declare DECLS) form, like `defmacro'.
The interpretation of the DECLS is determined by `defun-declarations-alist'.

** Minibuffer

*** `read-regexp' has a new argument HISTORY; the first argument PROMPT
of `read-regexp' accepts a string ending with a colon and space, and its
second argument DEFAULTS can be a list of strings accessible via `M-n'
in the minibuffer ahead of other hard-coded useful regexp-related values.
More commands use `read-regexp' now to read their regexp arguments.

** Completion

*** New function `completion-table-with-quoting' to handle completion
in the presence of quoting, such as file completion in shell buffers.

*** New function `completion-table-subvert' to use an existing completion
table, but with a different prefix.

** Debugger changes

*** New error type and new function `user-error'.
These do not trigger the debugger.

*** New option `debugger-bury-or-kill', saying what to do with the
debugger buffer when exiting debug.

*** Set `debug-on-message' to enter the debugger when a certain
message is displayed in the echo area.  This can be useful when trying
to work out which code is doing something.

*** New var `inhibit-debugger', automatically set to prevent accidental
recursive invocations.

** Window changes

*** The functions `get-lru-window', `get-mru-window' and `get-largest-window'
now accept a third argument to avoid choosing the selected window.

*** Additional values recognized for option `window-combination-limit'.

*** New macro `with-temp-buffer-window', similar to
`with-output-to-temp-buffer'.

*** `temp-buffer-resize-mode' no longer resizes windows that have been
reused.

*** New command `fit-frame-to-buffer' adjusts the frame height to
fit the contents.

*** The command `fit-window-to-buffer' can adjust the frame height
if the new option `fit-frame-to-buffer' is non-nil.

*** New option `switch-to-buffer-preserve-window-point' to restore a
window's point when switching buffers.

*** New display action functions `display-buffer-below-selected',
and `display-buffer-in-previous-window'.

*** New display action alist entry `inhibit-switch-frame', if non-nil,
tells display action functions to avoid changing which frame is
selected.

*** New display action alist entry `pop-up-frame-parameters', if
non-nil, specifies frame parameters to give any newly-created frame.

*** New display action alist entry `previous-window', if non-nil,
specifies window to reuse in `display-buffer-in-previous-window'.

*** New display action alist entries `window-height' and `window-width'
specify the size of new windows created by `display-buffer'.

*** The following variables are obsolete, as they can be replaced by
appropriate entries in the `display-buffer-alist' function introduced
in Emacs 24.1:
**** `dired-shrink-to-fit'
**** `display-buffer-reuse-frames'
**** `display-buffer-function'
**** `special-display-buffer-names'
**** `special-display-frame-alist'
**** `special-display-function'