GNU Emacs NEWS -- history of user-visible changes. Copyright (C) 2014-2017 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 26. See file HISTORY for a list of GNU Emacs versions and release dates. See files NEWS.25, NEWS.24, 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. Temporary note: +++ indicates that all necessary documentation updates are complete. (This means all relevant manuals in doc/ AND lisp doc-strings.) --- means no change in the manuals is needed. When you add a new item, use the appropriate mark if you are sure it applies, * Installation Changes in Emacs 26.1 ** By default libgnutls is now required when building Emacs. Use 'configure --with-gnutls=no' to build even when GnuTLS is missing. ** GnuTLS version 2.12.2 or later is now required, instead of merely version 2.6.6 or later. ** The new option 'configure --with-mailutils' causes Emacs to rely on GNU Mailutils 'movemail' to retrieve email. By default, the Emacs build procedure continues to build and install a limited and insecure 'movemail' substitute. Although --with-mailutils is recommended, it is not yet the default due to backward-compatibility concerns. ** The new option 'configure --enable-gcc-warnings=warn-only' causes GCC to issue warnings without stopping the build. This behavior is now the default in developer builds. As before, use '--disable-gcc-warnings' to suppress GCC's warnings, and '--enable-gcc-warnings' to stop the build if GCC issues warnings. ** When GCC warnings are enabled, '--enable-check-lisp-object-type' is now enabled by default when configuring. +++ ** The Emacs server now has socket-launching support. This allows socket based activation, where an external process like systemd can invoke the Emacs server process upon a socket connection event and hand the socket over to Emacs. Emacs uses this socket to service emacsclient commands. This new functionality can be disabled with the configure option '--disable-libsystemd'. +++ ** A systemd user unit file is provided. Use it in the standard way: systemctl --user enable emacs (If your Emacs is installed in a non-standard location, you may need to copy the emacs.service file to eg ~/.config/systemd/user/) ** New configure option '--disable-build-details' attempts to build an Emacs that is more likely to be reproducible; that is, if you build and install Emacs twice, the second Emacs is a copy of the first. Deterministic builds omit the build date from the output of the emacs-version and erc-cmd-SV functions, and the leave the following variables nil: emacs-build-system, emacs-build-time, erc-emacs-build-time. ** The configure option '--with-gameuser' now defaults to 'no', as this appears to be the most common configuration in practice. When it is 'no', the shared game directory and the auxiliary program update-game-score are no longer needed and are not installed. ** Emacs no longer works on IRIX. We expect that Emacs users are not affected by this, as SGI stopped supporting IRIX in December 2013. * Startup Changes in Emacs 26.1 +++ ** New option '--fg-daemon'. This is the same as '--daemon', except it runs in the foreground and does not fork. This is intended for modern init systems such as systemd, which manage many of the traditional aspects of daemon behavior themselves. '--bg-daemon' is now an alias for '--daemon'. +++ ** Emacs now supports 24-bit colors on capable text terminals Terminal is automatically initialized to use 24-bit colors if the required capabilities are found in terminfo. See the FAQ node "Colors on a TTY" for more information. * Changes in Emacs 26.1 ** The variable 'emacs-version' no longer includes the build number. This is now stored separately in a new variable, 'emacs-build-number'. +++ ** The new function 'mapbacktrace' applies a function to all frames of the current stack trace. +++ ** Emacs now provides a limited form of concurrency with Lisp threads. Concurrency in Emacs Lisp is "mostly cooperative", meaning that Emacs will only switch execution between threads at well-defined times: when Emacs waits for input, during blocking operations related to threads (such as mutex locking), or when the current thread explicitly yields. Global variables are shared among all threads, but a 'let' binding is thread-local. Each thread also has its own current buffer and its own match data. See the chapter "Threads" in the ELisp manual for full documentation of these facilities. +++ ** The new function 'file-name-case-insensitive-p' tests whether a given file is on a case-insensitive filesystem. +++ ** The new user variable 'electric-quote-chars' provides a list of curved quotes for 'electric-quote-mode', allowing user to choose the types of quotes to be used. +++ ** The new user variable 'dired-omit-case-fold' allows the user to customize the case-sensitivity of dired-omit-mode. It defaults to the same sensitivity as that of the filesystem for the corresponding dired buffer. +++ ** Emacs now uses double buffering to reduce flicker when editing and resizing graphical Emacs frames on the X Window System. This support requires the DOUBLE-BUFFER extension, which major X servers have supported for many years. If your system has this extension, but an Emacs built with double buffering misbehaves on some displays you use, you can disable the feature by adding '(inhibit-double-buffering . t) to default-frame-alist. Or inject this parameter into the selected frame by evaluating this form: (modify-frame-parameters nil '((inhibit-double-buffering . t))) --- The group 'wp', whose label was "text", is now deprecated. Use the new group 'text', which inherits from 'wp', instead. +++ ** The new function 'call-shell-region' executes a command in an inferior shell with the buffer region as input. +++ ** The new user option 'shell-command-dont-erase-buffer' controls if the output buffer is erased between shell commands; if non-nil, the output buffer is not erased; this variable also controls where to set the point in the output buffer: beginning of the output, end of the buffer or save the point. When 'shell-command-dont-erase-buffer' is nil, the default value, the behavior of 'shell-command', 'shell-command-on-region' and 'async-shell-command' is as usual. +++ ** The new user option 'mouse-select-region-move-to-beginning' controls the position of point when double-clicking mouse-1 on the end of a parenthetical grouping or string-delimiter: the default value nil keeps point at the end of the region, setting it to non-nil moves point to the beginning of the region. +++ ** The new user option 'mouse-drag-and-drop-region' allows to drag the entire region of text to another place or another buffer. +++ ** The new user option 'confirm-kill-processes' allows the user to skip a confirmation prompt for killing subprocesses when exiting Emacs. When set to t (the default), Emacs will prompt for confirmation before killing subprocesses on exit, which is the same behavior as before. --- ** 'find-library-name' will now fall back on looking at 'load-history' to try to locate libraries that have been loaded with an explicit path outside 'load-path'. +++ ** Faces in 'minibuffer-prompt-properties' no longer overwrite properties in the text in functions like 'read-from-minibuffer', but instead are added to the end of the face list. This allows users to say things like '(read-from-minibuffer (propertize "Enter something: " 'face 'bold))'. +++ ** The new variable 'extended-command-suggest-shorter' has been added to control whether to suggest shorter 'M-x' commands or not. --- ** icomplete now respects 'completion-ignored-extensions'. +++ ** Non-breaking hyphens are now displayed with the 'nobreak-hyphen' face instead of the 'escape-glyph' face. +++ ** Approximations to quotes are now displayed with the new 'homoglyph' face instead of the 'escape-glyph' face. --- ** 'C-x h' ('mark-whole-buffer') will now avoid marking the prompt part of minibuffers. --- ** 'find-library' now takes a prefix argument to pop to a different window. --- ** 'process-attributes' on Darwin systems now returns more information. +++ ** Several accessors for the value returned by 'file-attributes' have been added. They are: 'file-attribute-type', 'file-attribute-link-number', 'file-attribute-user-id', 'file-attribute-group-id', 'file-attribute-access-time', 'file-attribute-modification-time', 'file-attribute-status-change-time', 'file-attribute-size', 'file-attribute-modes', 'file-attribute-inode-number', 'file-attribute-device-number' and 'file-attribute-collect'. +++ ** The new function 'buffer-hash' computes a fast, non-consing hash of a buffer's contents. --- ** 'fill-paragraph' no longer marks the buffer as changed unless it actually changed something. --- ** The locale language name 'ca' is now mapped to the language environment 'Catalan', which has been added. --- ** 'align-regexp' has a separate history for its interactive argument. 'align-regexp' no longer shares its history with all other history-less functions that use 'read-string'. +++ ** The networking code has been reworked so that it's more asynchronous than it was (when specifying :nowait t in 'make-network-process'). How asynchronous it is varies based on the capabilities of the system, but on a typical GNU/Linux system the DNS resolution, the connection, and (for TLS streams) the TLS negotiation are all done without blocking the main Emacs thread. To get asynchronous TLS, the TLS boot parameters have to be passed in (see the manual for details). Certain process oriented functions (like 'process-datagram-address') will block until socket setup has been performed. The recommended way to deal with asynchronous sockets is to avoid interacting with them until they have changed status to "run". This is most easily done from a process sentinel. ** 'make-network-process' and 'open-network-stream' sometimes allowed :service to be an integer string (e.g., :service "993") and sometimes required an integer (e.g., :service 993). This difference has been eliminated, and integer strings work everywhere. ** It is possible to disable attempted recovery on fatal signals. Two new variables support disabling attempts to recover from stack overflow and to avoid automatic auto-save when Emacs is delivered a fatal signal. 'attempt-stack-overflow-recovery', if set to 'nil', will disable attempts to recover from C stack overflows; Emacs will then crash as with any other fatal signal. 'attempt-orderly-shutdown-on-fatal-signal', if set to 'nil', will disable attempts to auto-save the session and shut down in an orderly fashion when Emacs receives a fatal signal; instead, Emacs will terminate immediately. Both variables are non-'nil' by default. These variables are for users who would like to avoid the small probability of data corruption due to techniques Emacs uses to recover in these situations. +++ ** File local and directory local variables are now initialized each time the major mode is set, not just when the file is first visited. These local variables will thus not vanish on setting a major mode. +++ ** A second dir-local file (.dir-locals-2.el) is now accepted. See the variable 'dir-locals-file-2' for more information. +++ ** Connection-local variables can be used to specify local variables with a value depending on the connected remote server. For details, see the node "Connection Local Variables" in the ELisp manual. --- ** International domain names (IDNA) are now encoded via the new puny.el library, so that one can visit web sites with non-ASCII URLs. +++ ** The new 'timer-list' command lists all active timers in a buffer, where you can cancel them with the 'c' command. +++ ** The new function 'read-multiple-choice' prompts for multiple-choice questions, with a handy way to display help texts. +++ ** 'switch-to-buffer-preserve-window-point' now defaults to t. +++ ** The new variable 'debugger-stack-frame-as-list' allows displaying all call stack frames in a Lisp backtrace buffer as lists. Both debug.el and edebug.el have been updated to heed to this variable. +++ ** The new variable 'x-ctrl-keysym' has been added to the existing roster of X keysyms. It can be used in combination with another variable of this kind to swap modifiers in Emacs. --- ** New input methods: 'cyrillic-tuvan', 'polish-prefix'. +++ ** File name quoting by adding the prefix "/:" is now possible for the local part of a remote file name. Thus, if you have a directory named "/~" on the remote host "foo", you can prevent it from being substituted by a home directory by writing it as "/foo:/:/~/file". +++ ** The new variable 'maximum-scroll-margin' allows having effective settings of 'scroll-margin' up to half the window size, instead of always restricting the margin to a quarter of the window. +++ ** Emacs can scroll horizontally using mouse, touchpad, and trackbar. You can enable this by customizing 'mwheel-tilt-scroll-p'. If you want to reverse the direction of the scroll, customize 'mwheel-flip-direction'. +++ ** Emacsclient has a new option -u/--suppress-output. The option suppresses display of return values from the server process. --- ** New user option 'dig-program-options' and extended functionality for DNS-querying functions 'nslookup-host', 'dns-lookup-host', and 'run-dig'. Each function now accepts an optional name server argument interactively (with a prefix argument) and non-interactively. +++ ** Emacsclient has a new option -T/--tramp. This helps with using a local Emacs session as the server for a remote emacsclient. With appropriate setup, one can now set the EDITOR environment variable on a remote machine to emacsclient, and use the local Emacs to edit remote files via Tramp. See the node "emacsclient Options" in the user manual for the details. +++ ** The new variable 'eval-expression-print-maximum-character' prevents large integers from being displayed as characters. ** Two new commands for finding the source code of Emacs Lisp libraries: 'find-library-other-window' and 'find-library-other-frame'. ** You can now provide explicit field numbers in format specifiers. For example, '(format "%2$s %1$s" "X" "Y")' produces "Y X". * Editing Changes in Emacs 26.1 +++ ** New variable 'column-number-indicator-zero-based'. Traditionally, in Column Number mode, the displayed column number counts from zero starting at the left margin of the window. This behavior is now controlled by 'column-number-indicator-zero-based'. If you would prefer for the displayed column number to count from one, you may set this variable to nil. (Behind the scenes, there is now a new mode line construct, '%C', which operates exactly as '%c' does except that it counts from one.) +++ ** New single-line horizontal scrolling mode. The 'auto-hscroll-mode' variable can now have a new special value, 'current-line', which causes only the line where the cursor is displayed to be horizontally scrolled when lines are truncated on display and point moves outside the left or right window margin. +++ ** New mode line constructs '%o' and '%q', and user option 'mode-line-percent-position'. '%o' displays the "degree of travel" of the window through the buffer. Unlike the default '%p', this percentage approaches 100% as the window approaches the end of the buffer. '%q' displays the percentage offsets of both the start and the end of the window, e.g. "5-17%". The new option 'mode-line-percent-position' makes it easier to switch between '%p', '%P', and these new constructs. +++ ** Two new user options 'list-matching-lines-jump-to-current-line' and 'list-matching-lines-current-line-face' to show highlighted the current line in *Occur* buffer. +++ ** The 'occur' command can now operate on the region. +++ ** New bindings for 'query-replace-map'. 'undo', undo the last replacement; bound to 'u'. 'undo-all', undo all replacements; bound to 'U'. ** 'delete-trailing-whitespace' deletes whitespace after form feed. In modes where form feed was treated as a whitespace character, 'delete-trailing-whitespace' would keep lines containing it unchanged. It now deletes whitespace after the last form feed thus behaving the same as in modes where the character is not whitespace. ** No more prompt about changed file when the file's content is unchanged. Instead of only checking the modification time, Emacs now also checks the file's actual content before prompting the user. ** Various casing improvements. *** 'upcase', 'upcase-region' et al. convert title case characters (such as Dz) into their upper case form (such as DZ). *** 'capitalize', 'upcase-initials' et al. make use of title-case forms of initial characters (correctly producing for example Džungla instead of incorrect DŽungla). *** Characters which turn into multiple ones when cased are correctly handled. For example, fi ligature is converted to FI when upper cased. *** Greek small sigma is correctly handled when at the end of the word. Strings such as ΌΣΟΣ are now correctly converted to Όσος when capitalized instead of incorrect Όσοσ (compare lowercase sigma at the end of the word). ** Emacs can now auto-save buffers to visited files in a more robust manner via the new mode 'auto-save-visited-mode'. Unlike 'auto-save-visited-file-name', this mode uses the normal saving procedure and therefore obeys saving hooks. 'auto-save-visited-file-name' is now obsolete. +++ ** New behavior of 'mark-defun' implemented Prefix argument selects that many (or that many more) defuns. Negative prefix arg flips the direction of selection. Also, 'mark-defun' between defuns correctly selects N following defuns (or -N previous for negative arguments). Finally, comments preceding the defun are selected unless they are separated from the defun by a blank line. * Changes in Specialized Modes and Packages in Emacs 26.1 *** smerge-refine-regions can refine regions in separate buffers *** Info menu and index completion uses substring completion by default. This can be customized via the info-menu category in completion-category-override. +++ *** The ancestor buffer is shown by default in 3way merges. A new option ediff-show-ancestor and a new toggle ediff-toggle-show-ancestor. ** TeX: Add luatex and xetex as alternatives to pdftex ** Electric-Buffer-menu +++ *** Key 'U' is bound to 'Buffer-menu-unmark-all' and key 'M-DEL' is bound to 'Buffer-menu-unmark-all-buffers'. ** bs --- *** Two new commands 'bs-unmark-all', bound to 'U', and 'bs-unmark-previous', bound to . ** Buffer-menu +++ *** Two new commands 'Buffer-menu-unmark-all', bound to 'U' and 'Buffer-menu-unmark-all-buffers', bound to 'M-DEL'. ** Gnus --- *** The .newsrc file will now only be saved if the native select method is an NNTP select method. +++ *** A new command for sorting articles by readedness marks has been added: 'C-c C-s C-m C-m'. ** Ibuffer --- *** New command 'ibuffer-jump'. --- *** New filter commands 'ibuffer-filter-by-basename', 'ibuffer-filter-by-file-extension', 'ibuffer-filter-by-directory', 'ibuffer-filter-by-starred-name', 'ibuffer-filter-by-modified' and 'ibuffer-filter-by-visiting-file'; bound respectively to '/b', '/.', '//', '/*', '/i' and '/v'. --- *** Two new commands 'ibuffer-filter-chosen-by-completion' and 'ibuffer-and-filter', the second bound to '/&'. --- *** The commands 'ibuffer-pop-filter', 'ibuffer-pop-filter-group', 'ibuffer-or-filter' and 'ibuffer-filter-disable' have the alternative bindings '/', '/S-', '/|' and '/DEL', respectively. --- *** The data format specifying filters has been extended to allow explicit logical 'and', and a more flexible form for logical 'not'. See 'ibuffer-filtering-qualifiers' doc string for full details. --- *** A new command 'ibuffer-copy-buffername-as-kill'; bound to 'B'. --- *** New command 'ibuffer-change-marks'; bound to '* c'. --- *** A new command 'ibuffer-mark-by-locked' to mark all locked buffers; bound to '% L'. --- *** A new option 'ibuffer-locked-char' to indicate locked buffers; Ibuffer shows a new column displaying 'ibuffer-locked-char' for locked buffers. --- *** A new command 'ibuffer-unmark-all-marks' to unmark all buffers without asking confirmation; bound to 'U'; 'ibuffer-do-replace-regexp' bound to 'r'. --- *** A new command 'ibuffer-mark-by-content-regexp' to mark buffers whose content matches a regexp; bound to '% g'. --- *** Two new options 'ibuffer-never-search-content-name' and 'ibuffer-never-search-content-mode' used by 'ibuffer-mark-by-content-regexp'. ** Browse-URL *** Support for opening links to man pages in Man or WoMan mode. ** Comint --- *** New user option 'comint-move-point-for-matching-input' to control where to place point after C-c M-r and C-c M-s. ** Compilation mode --- *** Messages from CMake are now recognized. +++ *** A new option 'dired-always-read-filesystem' default to nil. If non-nil, buffers visiting files are reverted before search them; for instance, in 'dired-mark-files-containing-regexp' a non-nil value of this option means the file is revisited in a temporary buffer; this temporary buffer is the actual buffer searched: the original buffer visiting the file is not modified. +++ *** In wdired, when editing files to contain slash characters, the resulting directories are automatically created. Whether to do this is controlled by the 'wdired-create-parent-directories' variable. +++ *** 'W' is now bound to 'browse-url-of-dired-file', and is useful for viewing HTML files and the like. ** Edebug *** Edebug can be prevented from pausing 1 second after reaching a breakpoint (e.g. with "f" and "o") by customizing the new option 'edebug-sit-on-break'. +++ *** New customizable option 'edebug-max-depth' This allows to enlarge the maximum recursion depth when instrumenting code. ** Eshell *** 'eshell-input-filter's value is now a named function 'eshell-input-filter-default', and has a new custom option 'eshell-input-filter-initial-space' to ignore adding commands prefixed with blank space to eshell history. ** eww +++ *** New 'M-RET' command for opening a link at point in a new eww buffer. +++ *** A new 's' command for switching to another eww buffer via the minibuffer. --- *** The 'o' command ('shr-save-contents') has moved to 'O' to avoid collision with the 'o' command from 'image-map'. +++ *** A new command 'C' ('eww-toggle-colors') can be used to toggle whether to use the HTML-specified colors or not. The user can also customize the 'shr-use-colors' variable. --- *** Images that are being loaded are now marked with gray "placeholder" images of the size specified by the HTML. They are then replaced by the real images asynchronously, which will also now respect width/height HTML specs (unless they specify widths/heights bigger than the current window). ** Ido *** The commands 'find-alternate-file-other-window', 'dired-other-window', 'dired-other-frame', and 'display-buffer-other-window' are now remapped to Ido equivalents if Ido mode is active. ** Images +++ *** Images are automatically scaled before displaying based on the 'image-scaling-factor' variable (if Emacs supports scaling the images in question). +++ *** Images inserted with 'insert-image' and related functions get a keymap put into the text properties (or overlays) that span the image. This keymap binds keystrokes for manipulating size and rotation, as well as saving the image to a file. These commands are also available in 'image-mode'. +++ *** A new library for creating and manipulating SVG images has been added. See the "SVG Images" section in the Lisp reference manual for details. +++ *** New setf-able function to access and set image parameters is provided: 'image-property'. --- *** New commands 'image-scroll-left' and 'image-scroll-right' for 'image-mode' that complement 'image-scroll-up' and 'image-scroll-down': they have the same prefix arg behavior and stop at image boundaries. ** Image-Dired *** Now provides a minor mode 'image-dired-minor-mode' which replaces the function 'image-dired-setup-dired-keybindings'. *** Thumbnail generation is now asynchronous The number of concurrent processes is limited by the variable 'image-dired-thumb-job-limit'. *** 'image-dired-thumbnail-storage' has a new option 'standard-large' for generating 256x256 thumbnails according to the Thumbnail Managing Standard. *** Inherits movement keys from 'image-mode' for viewing full images. This includes the usual char, line, and page movement commands. *** All the -options types have been changed to argument lists instead of shell command strings. This change affects 'image-dired-cmd-create-thumbnail-options', 'image-dired-cmd-create-temp-image-options', 'image-dired-cmd-rotate-thumbnail-options', 'image-dired-cmd-rotate-original-options', 'image-dired-cmd-write-exif-data-options', 'image-dired-cmd-read-exif-data-options', and introduces 'image-dired-cmd-pngnq-options', 'image-dired-cmd-pngcrush-options', 'image-dired-cmd-create-standard-thumbnail-options' *** Recognizes more tools by default, including pngnq-s9 and OptiPNG *** 'find-file' and related commands now work on thumbnails and displayed images, providing a default argument of the original file name via an addition to 'file-name-at-point-functions'. --- ** The default 'Info-default-directory-list' no longer checks some obsolete directory suffixes (gnu, gnu/lib, gnu/lib/emacs, emacs, lib, lib/emacs) when searching for info directories. +++ ** The commands that add ChangeLog entries now prefer a VCS root directory for the ChangeLog file, if none already exists. Customize 'change-log-directory-files' to nil for the old behavior. --- ** Support for non-string values of 'time-stamp-format' has been removed. ** Message --- *** 'message-use-idna' now defaults to t (because Emacs comes with built-in IDNA support now). --- *** When sending HTML messages with embedded images, and you have exiftool installed, and you rotate images with EXIF data (i.e., JPEGs), the rotational information will be inserted into the outgoing image in the message. (The original image will not have its orientation affected.) --- *** The 'message-valid-fqdn-regexp' variable has been removed, since there are now top-level domains added all the time. Message will no longer warn about sending emails to top-level domains it hasn't heard about. *** 'message-beginning-of-line' (bound to C-a) understands folded headers. In 'visual-line-mode' it will look for the true beginning of a header while in non-'visual-line-mode' it will move the point to the indented header's value. ** Package +++ *** The new variable 'package-gnupghome-dir' has been added to control where the GnuPG home directory (used for signature verification) is located and whether GnuPG's option "--homedir" is used or not. ** Tramp +++ *** The method part of remote file names is mandatory now. A valid remote file name starts with "/method:host:" or "/method:user@host:". +++ *** The new pseudo method "-" is a marker for the default method. "/-::" is the shortest remote file name then. +++ *** The command 'tramp-change-syntax' allows to choose an alternative remote file name syntax. +++ *** New connection method "sg", which supports editing files under a different group ID. +++ *** New connection method "doas" for OpenBSD hosts. +++ *** New connection method "gdrive", which allows to access Google Drive onsite repositories. +++ *** Gateway methods in Tramp have been removed. Instead, the Tramp manual documents how to configure ssh and PuTTY accordingly. +++ *** Setting the "ENV" environment variable in 'tramp-remote-process-environment' enables reading of shell initialization files. --- *** Variable 'tramp-completion-mode' is obsoleted. --- ** 'auto-revert-use-notify' is set back to t in 'global-auto-revert-mode'. --- ** JS mode now sets 'comment-multi-line' to t. ** CSS mode --- *** Support for completing attribute values, at-rules, bang-rules, HTML tags, classes and IDs using the 'completion-at-point' command. Completion candidates for HTML classes and IDs are retrieved from open HTML mode buffers. --- *** CSS mode now binds 'C-h S' to a function that will show information about a CSS construct (an at-rule, property, pseudo-class, pseudo-element, with the default being guessed from context). By default the information is looked up on the Mozilla Developer Network, but this can be customized using 'css-lookup-url-format'. --- *** CSS colors are fontified using the color they represent as the background. For instance, #ff0000 would be fontified with a red background. +++ ** Emacs now supports character name escape sequences in character and string literals. The syntax variants \N{character name} and \N{U+code} are supported. +++ ** Prog mode has some support for multi-mode indentation. This allows better indentation support in modes that support multiple programming languages in the same buffer, like literate programming environments or ANTLR programs with embedded Python code. A major mode can provide indentation context for a sub-mode through the 'prog-indentation-context' variable. To support this, modes that provide indentation should use 'prog-widen' instead of 'widen' and 'prog-first-column' instead of a literal zero. See the node "Mode-Specific Indent" in the ELisp manual for more details. ** ERC *** New variable 'erc-default-port-tls' used to connect to TLS IRC servers. ** URL +++ *** The new function 'url-cookie-delete-cookie' can be used to programmatically delete all cookies, or cookies from a specific domain. +++ *** 'url-retrieve-synchronously' now takes an optional timeout parameter. --- *** The URL package now support HTTPS over proxies supporting CONNECT. +++ *** 'url-user-agent' now defaults to 'default', and the User-Agent string is computed dynamically based on 'url-privacy-level'. ** VC and related modes --- *** The VC state indicator in the mode line now defaults to more colorful faces to make it more obvious to the user what the state is. See the 'vc-faces' customization group. +++ *** 'vc-dir-mode' now binds 'vc-log-outgoing' to 'O'; and has various branch-related commands on a keymap bound to 'B'. ** CC mode *** Opening a .h file will turn C or C++ mode depending on language used. This is done with the help of 'c-or-c++-mode' function which analyses contents of the buffer to determine whether it's a C or C++ source file. --- ** New DNS mode command 'dns-mode-ipv6-to-nibbles' to convert IPv6 addresses to a format suitable for reverse lookup zone files. ** Flymake +++ *** Emacs does no longer prompt the user before killing Flymake processes on exit. * New Modes and Packages in Emacs 26.1 ** New Elisp data-structure library 'radix-tree'. ** New library 'xdg' with utilities for some XDG standards and specs. ** HTML +++ *** A new submode of 'html-mode', 'mhtml-mode', is now the default mode for *.html files. This mode handles indentation, fontification, and commenting for embedded JavaScript and CSS. ** New minor mode 'pixel-scroll-mode' provides smooth pixel-level scrolling. * Incompatible Lisp Changes in Emacs 26.1 +++ *** Command 'dired-mark-extension' now automatically prepends a '.' to the extension when not present. The new command 'dired-mark-suffix' behaves similarly but it doesn't prepend a '.'. +++ ** Certain cond/pcase/cl-case forms are now compiled using a faster jump table implementation. This uses a new bytecode op 'switch', which isn't compatible with previous Emacs versions. This functionality can be disabled by setting 'byte-compile-cond-use-jump-table' to nil. ** 'C-up', 'C-down', 'C-left' and 'C-right' are now defined in term mode to send the same escape sequences that xterm does. This makes things like forward-word in readline work. --- ** hideshow mode got four key bindings that are analogous to outline mode bindings: 'C-c @ C-a', 'C-c @ C-t', 'C-c @ C-d', and 'C-c @ C-e.' ** The grep/rgrep/lgrep functions will now ask about saving files before running. This is controlled by the 'grep-save-buffers' variable. --- ** Customizable variable 'query-replace-from-to-separator' now doesn't propertize the string value of the separator. Instead, text properties are added by query-replace-read-from. Additionally, the new nil value restores pre-24.5 behavior of not providing replacement pairs via the history. ** Some obsolete functions, variables, and faces have been removed: *** make-variable-frame-local. Variables cannot be frame-local any more. *** From subr.el: window-dot, set-window-dot, read-input, show-buffer, eval-current-buffer, string-to-int *** All the default-FOO variables that hold the default value of the FOO variable. Use 'default-value' and 'setq-default' to access and change FOO, respectively. The exhaustive list of removed variables is: 'default-mode-line-format', 'default-header-line-format', 'default-line-spacing', 'default-abbrev-mode', 'default-ctl-arrow', 'default-truncate-lines', 'default-left-margin', 'default-tab-width', 'default-case-fold-search', 'default-left-margin-width', 'default-right-margin-width', 'default-left-fringe-width', 'default-right-fringe-width', 'default-fringes-outside-margins', 'default-scroll-bar-width', 'default-vertical-scroll-bar', 'default-indicate-empty-lines', 'default-indicate-buffer-boundaries', 'default-fringe-indicator-alist', 'default-fringe-cursor-alist', 'default-scroll-up-aggressively', 'default-scroll-down-aggressively', 'default-fill-column', 'default-cursor-type', 'default-cursor-in-non-selected-windows', 'default-buffer-file-coding-system', 'default-major-mode', and 'default-enable-multibyte-characters'. *** Many variables obsoleted in 22.1 referring to face symbols +++ ** The variable 'text-quoting-style' no longer affects the treatment of curved quotes in format arguments to functions like 'message' and 'format-message'. In particular, when this variable's value is 'grave', all quotes in formats are output as-is. ** Functions like 'check-declare-file' and 'check-declare-directory' now generate less chatter and more-compact diagnostics. The auxiliary function 'check-declare-errmsg' has been removed. +++ ** The regular expression character class [:blank:] now matches Unicode horizontal whitespace as defined in the Unicode Technical Standard #18. If you only want to match space and tab, use [ \t] instead. +++ ** 'min' and 'max' no longer round their results. Formerly, they returned a floating-point value if any argument was floating-point, which was sometimes numerically incorrect. For example, on a 64-bit host (max 1e16 10000000000000001) now returns its second argument instead of its first. +++ ** The variable 'old-style-backquotes' has been made internal and renamed to 'lread--old-style-backquotes'. No user code should use this variable. +++ ** Module functions are now implemented slightly differently; in particular, the function 'internal--module-call' has been removed. Code that depends on undocumented internals of the module system might break. * Lisp Changes in Emacs 26.1 ** New function 'seq-set-equal-p' to check if SEQUENCE1 and SEQUENCE2 contain the same elements, regardless of the order. +++ ** Emacs now supports records for user-defined types, via the new functions 'make-record', 'record', and 'recordp'. Records are now used internally to represent cl-defstruct and defclass instances, for example. +++ ** 'save-some-buffers' now uses 'save-some-buffers-default-predicate' to decide which buffers to ask about, if the PRED argument is nil. The default value of 'save-some-buffers-default-predicate' is nil, which means ask about all file-visiting buffers. ** string-(to|as|make)-(uni|multi)byte are now declared obsolete. ** New variable 'while-no-input-ignore-events' which allow setting which special events 'while-no-input' should ignore. It is a list of symbols. ** New function 'undo-amalgamate-change-group' to get rid of undo-boundaries between two states. ** New var 'definition-prefixes' is a hash table mapping prefixes to the files where corresponding definitions can be found. This can be used to fetch definitions that are not yet loaded, for example for 'C-h f'. ** New var 'syntax-ppss-table' to control the syntax-table used in 'syntax-ppss'. +++ ** 'define-derived-mode' can now specify an :after-hook form, which gets evaluated after the new mode's hook has run. This can be used to incorporate configuration changes made in the mode hook into the mode's setup. ** Autoload files can be generated without timestamps, by setting 'autoload-timestamps' to nil. FIXME As an experiment, nil is the current default. If no insurmountable problems before next release, it can stay that way. --- ** 'gnutls-boot' now takes a parameter ':complete-negotiation' that says that negotiation should complete even on non-blocking sockets. --- ** There is now a new variable 'flyspell-sort-corrections-function' that allows changing the way corrections are sorted. --- ** The new command 'fortune-message' has been added, which displays fortunes in the echo area. +++ ** New function 'func-arity' returns information about the argument list of an arbitrary function. This generalizes 'subr-arity' for functions that are not built-in primitives. We recommend using this new function instead of 'subr-arity'. ** New function 'region-bounds' can be used in the interactive spec to provide region boundaries (for rectangular regions more than one) to an interactively callable function as a single argument instead of two separate arguments region-beginning and region-end. +++ ** 'parse-partial-sexp' state has a new element. Element 10 is non-nil when the last character scanned might be the first character of a two character construct, i.e., a comment delimiter or escaped character. Its value is the syntax of that last character. +++ ** 'parse-partial-sexp's state, element 9, has now been confirmed as permanent and documented, and may be used by Lisp programs. Its value is a list of currently open parenthesis positions, starting with the outermost parenthesis. --- ** 'read-color' will now display the color names using the color itself as the background color. ** The function 'redirect-debugging-output' now works on platforms other than GNU/Linux. +++ ** The new function 'string-version-lessp' compares strings by interpreting consecutive runs of numerical characters as numbers, and compares their numerical values. According to this predicate, "foo2.png" is smaller than "foo12.png". --- ** Numeric comparisons and 'logb' no longer return incorrect answers due to internal rounding errors. For example, (< most-positive-fixnum (+ 1.0 most-positive-fixnum)) now correctly returns t on 64-bit hosts. --- ** The functions 'ffloor', 'fceiling', 'ftruncate' and 'fround' now accept only floating-point arguments, as per their documentation. Formerly, they quietly accepted integer arguments and sometimes returned nonsensical answers, e.g., (< N (ffloor N)) could return t. --- ** On hosts like GNU/Linux x86-64 where a 'long double' fraction contains at least EMACS_INT_WIDTH - 3 bits, 'format' no longer returns incorrect answers due to internal rounding errors when formatting Emacs integers with %e, %f, or %g conversions. For example, on these hosts (eql N (string-to-number (format "%.0f" N))) now returns t for all Emacs integers N. --- ** Calls that accept floating-point integers (for use on hosts with limited integer range) now signal an error if arguments are not integral. For example (decode-char 'ascii 0.5) now signals an error. +++ ** The new function 'char-from-name' converts a Unicode name string to the corresponding character code. +++ ** New functions 'sxhash-eq' and 'sxhash-eql' return hash codes of a Lisp object suitable for use with 'eq' and 'eql' correspondingly. If two objects are 'eq' ('eql'), then the result of 'sxhash-eq' ('sxhash-eql') on them will be the same. +++ ** Function 'sxhash' has been renamed to 'sxhash-equal' for consistency with the new functions. For compatibility, 'sxhash' remains as an alias to 'sxhash-equal'. +++ ** 'make-hash-table' now defaults to a rehash threshold of 0.8125 instead of 0.8, to avoid rounding glitches. +++ ** New function 'add-variable-watcher' can be used to call a function when a symbol's value is changed. This is used to implement the new debugger command 'debug-on-variable-change'. +++ ** Time conversion functions that accept a time zone rule argument now allow it to be OFFSET or a list (OFFSET ABBR), where the integer OFFSET is a count of seconds east of Universal Time, and the string ABBR is a time zone abbreviation. The affected functions are 'current-time-string', 'current-time-zone', 'decode-time', 'format-time-string', and 'set-time-zone-rule'. +++ ** 'format-time-string' now formats "%q" to the calendar quarter. ** New built-in function 'mapcan' which avoids unnecessary consing (and garbage collection). +++ ** 'car' and 'cdr' compositions 'cXXXr' and 'cXXXXr' are now part of Elisp. --- ** 'if-let*', 'when-let*', and 'and-let*' are new in subr-x.el. The incumbent 'if-let' and 'when-let' are now aliases. ** Low-level list functions like 'length' and 'member' now do a better job of signaling list cycles instead of looping indefinitely. +++ ** The new functions 'make-nearby-temp-file' and 'temporary-file-directory' can be used for creation of temporary files of remote or mounted directories. +++ ** The new function 'file-local-name' can be used to specify arguments of remote processes. +++ ** The new functions 'file-name-quote', 'file-name-unquote' and 'file-name-quoted-p' can be used to quote / unquote file names with the prefix "/:". +++ ** The new error 'file-missing', a subcategory of 'file-error', is now signaled instead of 'file-error' if a file operation acts on a file that does not exist. +++ ** The function 'delete-directory' no longer signals an error when operating recursively and when some other process deletes the directory or its files before 'delete-directory' gets to them. +++ *** New error type 'user-search-failed' like 'search-failed' but avoids debugger like 'user-error'. ** Changes in Frame- and Window- Handling +++ *** Resizing a frame no longer runs 'window-configuration-change-hook'. 'window-size-change-functions' should be used instead. +++ *** The new function 'frame-size-changed-p' can tell whether a frame has been resized since the last time 'window-size-change-functions' has been run. +++ *** The function 'frame-geometry' now also returns the width of a frame's outer border. +++ *** New frame parameters +++ **** 'z-group' positions a frame above or below all others. +++ **** 'min-width' and 'min-height' specify the absolute minimum size of a frame. +++ **** 'parent-frame' makes a frame the child frame of another Emacs frame. The section "Child Frames" in the Elisp manual describes the intrinsics of that relationship. +++ **** 'delete-before' triggers deletion of one frame before that of another. +++ **** 'mouse-wheel-frame' specifies another frame whose windows shall be scrolled instead. +++ **** 'no-other-frame' has 'next-frame' and 'previous-frame' skip this frame. +++ **** 'skip-taskbar' removes a frame's icon from the taskbar and has Alt- skip this frame. +++ **** 'no-focus-on-map' avoids that a frame gets input focus when mapped. +++ **** 'no-accept-focus' means that a frame does not want to get input focus via the mouse. +++ **** 'undecorated' removes the window manager decorations from a frame. +++ **** 'override-redirect' tells the window manager to disregard this frame. +++ *** The 'width' and 'height' frame parameters allow to specify pixel values now. +++ *** The new function 'frame-list-z-order' returns a list of all frames in Z (stacking) order. +++ *** The function 'x-focus-frame' optionally tries to not activate its frame. +++ *** The variable 'focus-follows-mouse' has a third meaningful value 'auto-raise' to indicate that the window manager automatically raises a frame when the mouse pointer enters it. +++ *** The new function 'frame-restack' puts a frame above or below another on the display. +++ *** The new face 'internal-border' specifies the background of a frame's internal border. +++ *** The NORECORD argument of 'select-window' now has a meaningful value 'mark-for-redisplay' which is like any other non-nil value but marks WINDOW for redisplay. +++ *** Support for side windows is now official. The display action function 'display-buffer-in-side-window' will display its buffer in a side window. Functions for toggling all side windows on a frame, changing and reversing the layout of side windows and returning the main (major non-side) window of a frame are provided. For details consult the section "Side Windows" in the Elisp manual. +++ *** Support for atomic windows - rectangular compositions of windows treated by 'split-window', 'delete-window' and 'delete-other-windows' like a single live window - is now official. For details consult the section "Atomic Windows" in the Elisp manual. +++ *** New 'display-buffer' alist entry 'window-parameters' allows to assign window parameters to the window used for displaying the buffer. +++ *** New function 'display-buffer-reuse-mode-window' is an action function suitable for use in 'display-buffer-alist'. For example, to avoid creating a new window when opening man pages when there's already one, use (add-to-list 'display-buffer-alist '("\\`\\*Man .*\\*\\'" . (display-buffer-reuse-mode-window (inhibit-same-window . nil) (mode . Man-mode)))) +++ *** New window parameter 'no-delete-other-window' prevents that its window gets deleted by 'delete-other-windows'. +++ *** New command 'window-swap-states' swaps the states of two live windows. +++ *** New functions 'window-pixel-width-before-size-change' and 'window-pixel-height-before-size-change' support detecting which window changed size when 'window-size-change-functions' are run. +++ *** The semantics of 'mouse-autoselect-window' has changed slightly. For details see the section "Mouse Window Auto-selection" in the Elisp manual. * Changes in Emacs 26.1 on Non-Free Operating Systems ** Intercepting hotkeys on Windows 7 and later now works better. The new keyboard hooking code properly grabs system hotkeys such as Win-* and Alt-TAB, in a way that Emacs can get at them before the system. This makes the 'w32-register-hot-key' functionality work again on all versions of MS-Windows starting with Windows 7. On Windows NT and later you can now register any hotkey combination. (On Windows 9X, the previous limitations, spelled out in the Emacs manual, still apply.) ** 'convert-standard-filename' no longer mirrors slashes on MS-Windows. Previously, on MS-Windows this function converted slash characters in file names into backslashes. It no longer does that. If your Lisp program used 'convert-standard-filename' to prepare file names to be passed to subprocesses (which is not the recommended usage of that function), you will now have to mirror slashes in your application code. One possible way is this: (let ((start 0)) (while (string-match "/" file-name start) (aset file-name (match-beginning 0) ?\\) (setq start (match-end 0)))) ** GUI sessions now treat SIGINT like Posix platforms do. The effect of delivering a Ctrl-C (SIGINT) signal to a GUI Emacs on MS-Windows is now the same as on Posix platforms -- Emacs saves the session and exits. In particular, this will happen if you start emacs.exe from the Windows shell, then type Ctrl-C into that shell's window. --- ** 'signal-process' supports SIGTRAP on Windows XP and later. The 'kill' emulation on Windows now maps SIGTRAP to a call to the 'DebugBreakProcess' API. This causes the receiving process to break execution and return control to the debugger. If no debugger is attached to the receiving process, the call is typically ignored. This is in contrast to the default action on POSIX Systems, where it causes the receiving process to terminate with a core dump if no debugger has been attached to it. ** `set-mouse-position' and `set-mouse-absolute-pixel-position' work on macOS. ---------------------------------------------------------------------- This file is part of GNU Emacs. GNU Emacs is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version. GNU Emacs is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with GNU Emacs. If not, see . Local variables: coding: utf-8 mode: outline paragraph-separate: "[ ]*$" end: