-@c -*-texinfo-*-
-@c This is part of the GNU Emacs Lisp Reference Manual.
-@c Copyright (C) 1999, 2002, 2003, 2004, 2005,
-@c 2006, 2007, 2008 Free Software Foundation, Inc.
-@c See the file elisp.texi for copying conditions.
-
-@c This node must have no pointers.
-
-@node Antinews, GNU Free Documentation License, System Interface, Top
-@appendix Emacs 21 Antinews
-
-For those users who live backwards in time, here is information about
-downgrading to Emacs version 21.4. We hope you will enjoy the greater
-simplicity that results from the absence of many Emacs @value{EMACSVER}
-features.
-
-@section Old Lisp Features in Emacs 21
-
-@itemize @bullet
-@item
-Many unnecessary features of redisplay have been eliminated. (The
-earlier major release, Emacs 20, will have a completely rewritten
-redisplay engine, which will be even simpler.)
-
-@itemize @minus
-@item
-The function @code{redisplay} has been removed. To update the display
-without delay, call @code{(sit-for 0)}. Since it is generally
-considered wasteful to update the display if there are any pending
-input events, no replacement for @code{(redisplay t)} is provided.
-
-@item
-The function @code{force-window-update} has been removed. It
-shouldn't be needed, since changes in window contents are detected
-automatically. In case they aren't, call @code{redraw-display} to
-redraw everything.
-
-@item
-Point no longer moves out from underneath invisible text at the end of
-each command. This allows the user to detect invisible text by moving
-the cursor around---if the cursor gets stuck, there is something
-invisible in the way. If you really want cursor motion to ignore the
-text, try marking it as intangible.
-
-@item
-Support for image maps and image slices has been removed. Emacs was
-always meant for editing text, anyway.
-
-@item
-The mode line now accepts all text properties, as well as
-@code{:propertize} and @code{:eval} forms, regardless of the
-@code{risky-local-variable} property.
-
-@item
-The @code{line-height} and @code{line-spacing} properties no longer
-have any meaning for newline characters. Such properties wouldn't
-make sense, since newlines are not really characters; they just tell
-you where to break a line.
-
-@item
-Considerable simplifications have been made to the display
-specification @code{(space . @var{props})}, which is used for
-displaying a space of specified width and height. Pixel-based
-specifications and Lisp expressions are no longer accepted.
-
-@item
-Many features associated with the fringe areas have been removed, to
-encourage people to concentrate on the main editing area (the fringe
-will be completely removed in Emacs 20.) Arbitrary bitmaps can no
-longer be displayed in the fringe; an overlay arrow can still be
-displayed, but there can only be one overlay arrow at a time (any more
-would be confusing.) The fringe widths cannot be adjusted, and
-individual windows cannot have their own fringe settings. A mouse
-click on the fringe no longer generates a special event.
-
-@item
-Individual windows cannot have their own scroll-bar settings.
-
-@item
-You can no longer use @samp{default} in a @code{defface} to specify
-defaults for subsequent faces.
-
-@item
-The function @code{display-supports-face-attributes-p} has been
-removed. In @code{defface} specifications, the @code{supports}
-predicate is no longer supported.
-
-@item
-The functions @code{merge-face-attribute} and
-@code{face-attribute-relative-p} have been removed.
-
-@item
-The priority of faces in a list supplied by the @code{:inherit} face
-attribute has been reversed. We like to make changes like this once
-in a while, to keep Emacs Lisp programmers on their toes.
-
-@item
-The @code{min-colors} face attribute, used for tailoring faces to
-limited-color displays, does not exist. If in doubt, use colors like
-``white'' and ``black,'' which ought to be defined everywhere.
-
-@item
-The @code{tty-color-mode} frame parameter does not exist. You should
-just trust the terminal capabilities database.
-@end itemize
-
-@item
-Several simplifications have been made to mouse support:
-
-@itemize @minus
-@item
-Clicking @kbd{mouse-1} won't follow links, as that is alien to the
-spirit of Emacs. Therefore, the @code{follow-link} property doesn't
-have any special meaning, and the function @code{mouse-on-link-p} has
-been removed.
-
-@item
-The variable @code{void-text-area-pointer} has been removed, so the
-mouse pointer shape remains unchanged when moving between valid text
-areas and void text areas. The @code{pointer} image and text
-properties are no longer supported.
-
-@item
-Mouse events will no longer specify the timestamp, the object clicked,
-equivalent buffer positions (for marginal or fringe areas), glyph
-coordinates, or relative pixel coordinates.
-@end itemize
-
-@item
-Simplifications have also been made to the way Emacs handles keymaps
-and key sequences:
-
-@itemize @minus
-@item
-The @code{kbd} macro is now obsolete and is no longer documented.
-It isn't that difficult to write key sequences using the string and
-vector representations, and we want to encourage users to learn.
-
-@item
-Emacs no longer supports key remapping. You can do pretty much the
-same thing with @code{substitute-key-definition}, or by advising the
-relevant command.
-
-@item
-The @code{keymap} text and overlay property is now overridden by minor
-mode keymaps, and will not work at the ends of text properties and
-overlays.
-
-@item
-The functions @code{map-keymap}, @code{keymap-prompt}, and
-@code{current-active-maps} have been removed.
-@end itemize
-
-@item
-Process support has been pared down to a functional minimum. The
-functions @code{call-process-shell-command} and @code{process-file}
-have been deleted. Processes no longer maintain property lists, and
-they won't ask any questions when the user tries to exit Emacs (which
-would simply be rude.) The function @code{signal-process} won't
-accept a process object, only the process id; determining the process
-id from a process object is left as an exercise to the programmer.
-
-@item
-Networking has also been simplified: @code{make-network-process} and
-its various associated function have all been replaced with a single
-easy-to-use function, @code{open-network-stream}, which can't use UDP,
-can't act as a server, and can't set up non-blocking connections.
-Also, deleting a network process with @code{delete-process} won't call
-the sentinel.
-
-@item
-Many programming shortcuts have been deleted, to provide you with the
-enjoyment of ``rolling your own.'' The macros @code{while-no-input},
-@code{with-local-quit}, and @code{with-selected-window}, along with
-@code{dynamic-completion-table} and @code{lazy-completion-table} no
-longer exist. Also, there are no built-in progress reporters;
-with Emacs, you can take progress for granted.
-
-@item
-Variable aliases are no longer supported. Aliases are for functions,
-not for variables.
-
-@item
-The variables @code{most-positive-fixnum} and
-@code{most-negative-fixnum} do not exist. On 32 bit machines, the
-most positive integer is probably 134217727, and the most negative
-integer is probably -134217728.
-
-@item
-The functions @code{eql} and @code{macroexpand-all} are no longer
-available. However, you can find similar functions in the @code{cl}
-package.
-
-@item
-The list returned by @code{split-string} won't include null substrings
-for separators at the beginning or end of a string. If you want to
-check for such separators, do it separately.
-
-@item
-The function @code{assoc-string} has been removed. Use
-@code{assoc-ignore-case} or @code{assoc-ignore-representation} (which
-are no longer obsolete.)
-
-@item
-The escape sequence @samp{\s} is always interpreted as a super
-modifier, never a space.
-
-@item
-The variable @code{buffer-save-without-query} has been removed, to
-prevent Emacs from sneakily saving buffers. Also, the hook
-@code{before-save-hook} has been removed, so if you want something to
-be done before saving, advise or redefine @code{basic-save-buffer}.
-
-@item
-The variable @code{buffer-auto-save-file-format} has been renamed to
-@code{auto-save-file-format}, and is no longer a permanent local.
-
-@item
-The function @code{visited-file-modtime} now returns a cons, instead
-of a list of two integers. The primitive @code{set-file-times} has
-been eliminated.
-
-@item
-The function @code{file-remote-p} is no longer available.
-
-@item
-When determining the filename extension, a leading dot in a filename
-is no longer ignored. Thus, @file{.emacs} is considered to have
-extension @file{emacs}, rather than being extensionless.
-
-@item
-Emacs looks for special file handlers in a more efficient manner: it
-will choose the first matching handler in
-@code{file-name-handler-alist}, rather than trying to figure out which
-provides the closest match.
-
-@item
-The @code{predicate} argument for @code{read-file-name} has been
-removed, and so have the variables @code{read-file-name-function} and
-@code{read-file-name-completion-ignore-case}. The function
-@code{read-directory-name} has also been removed.
-
-@item
-The functions @code{all-completions} and @code{try-completion} will no
-longer accept lists of strings or hash tables (it will still accept
-alists, obarrays, and functions.) In addition, the function
-@code{test-completion} is no longer available.
-
-@item
-The @samp{G} interactive code character is no longer supported.
-Use @samp{F} instead.
-
-@item
-Arbitrary Lisp functions can no longer be recorded into
-@code{buffer-undo-list}. As a consequence, @code{yank-undo-function}
-is obsolete, and has been removed.
-
-@item
-Emacs will never complain about commands that accumulate too much undo
-information, so you no longer have to worry about binding
-@code{buffer-undo-list} to @code{t} for such commands (though you may
-want to do that anyway, to avoid taking up unnecessary memory space.)
-
-@item
-Atomic change groups are no longer supported.
-
-@item
-The list returned by @code{(match-data t)} no longer records the
-buffer as a final element.
-
-@item
-The function @code{looking-back} has been removed, so we no longer
-have the benefit of hindsight.
-
-@item
-The variable @code{search-spaces-regexp} does not exist. Spaces
-always stand for themselves in regular expression searches.
-
-@item
-The functions @code{skip-chars-forward} and @code{skip-chars-backward}
-no longer accepts character classes such as @samp{[:alpha:]}. All
-characters are created equal.
-
-@item
-The @code{yank-handler} text property no longer has any meaning.
-Also, @code{yank-excluded-properties}, @code{insert-for-yank}, and
-@code{insert-buffer-substring-as-yank} have all been removed.
-
-@item
-The variable @code{char-property-alias-alist} has been deleted.
-Aliases are for functions, not for properties.
-
-@item
-The function @code{get-char-property-and-overlay} has been deleted.
-If you want the properties at a point, find the text properties at the
-point; then, find the overlays at the point, and find the properties
-on those overlays.
-
-@item
-Font Lock mode only manages @code{face} properties; you can't use
-font-lock keywords to specify arbitrary text properties for it to
-manage. After all, it is called Font Lock mode, not Arbitrary
-Properties Lock mode.
-
-@item
-The arguments to @code{remove-overlays} are no longer optional.
-
-@item
-In @code{replace-match}, the replacement text now inherits properties
-from the surrounding text.
-
-@item
-The variable @code{mode-line-format} no longer supports the @code{:propertize},
-@code{%i}, and @code{%I} constructs. The function
-@code{format-mode-line} has been removed.
-
-@item
-The functions @code{window-inside-edges} and @code{window-body-height}
-have been removed. You should do the relevant calculations yourself,
-starting with @code{window-width} and @code{window-height}.
-
-@item
-The functions @code{window-pixel-edges} and
-@code{window-inside-pixel-edges} have been removed. We prefer to
-think in terms of lines and columns, not pixel coordinates. (Sometime
-in the distant past, we will do away with graphical terminals
-entirely, in favor of text terminals.) For similar reasons, the
-functions @code{posn-at-point}, @code{posn-at-x-y}, and
-@code{window-line-height} have been removed, and
-@code{pos-visible-in-window-p} no longer worries about partially
-visible rows.
-
-@item
-The macro @code{save-selected-window} only saves the selected window
-of the selected frame, so don't try selecting windows in other frames.
-
-@item
-The function @code{minibufferp} is no longer available.
-
-@item
-The function @code{modify-all-frames-parameters} has been removed (we
-always suspected the name was ungrammatical, anyway.)
-
-@item
-The @code{line-spacing} variable no longer accepts float values.
-
-@item
-The function @code{tool-bar-local-item-from-menu} has been deleted.
-If you need to make an entry in the tool bar, you can still use
-@code{tool-bar-add-item-from-menu}, but that modifies the binding in
-the source keymap instead of copying it into the local keymap.
-
-@item
-When determining the major mode, the file name takes precedence over
-the interpreter magic line. The variable @code{magic-mode-alist},
-which associates certain buffer beginnings with major modes, has been
-eliminated.
-
-@item
-The hook @code{after-change-major-mode-hook} is not defined, and
-neither are @code{run-mode-hooks} and @code{delay-mode-hooks}.
-
-@item
-The variable @code{minor-mode-list} has been removed.
-
-@item
-@code{define-derived-mode} will copy abbrevs from the parent mode's
-abbrev table, instead of creating a new, empty abbrev table.
-
-@item
-There are no ``system'' abbrevs. When the user saves into the abbrevs
-file, all abbrevs are saved.
-
-@item
-The Warnings facility has been removed. Just use @code{error}.
-
-@item
-Several hook variables have been renamed to flout the Emacs naming
-conventions. We feel that consistency is boring, and having
-non-standard hook names encourages users to check the documentation
-before using a hook. For instance, the normal hook
-@code{find-file-hook} has been renamed to @code{find-file-hooks}, and
-the abnormal hook @code{delete-frame-functions} has been renamed to
-@code{delete-frame-hook}.
-
-@item
-The function @code{symbol-file} does not exist. If you want to know
-which file defined a function or variable, try grepping for it.
-
-@item
-The variable @code{load-history} records function definitions just
-like variable definitions, instead of indicating which functions were
-previously autoloaded.
-
-@item
-There is a new variable, @code{recursive-load-depth-limit}, which
-specifies how many times files can recursively load themselves; it is
-50 by default, and @code{nil} means infinity. Previously, Emacs signaled an
-error after just 3 recursive loads, which was boring.
-
-@item
-Byte-compiler warnings and error messages will leave out the line and
-character positions, in order to exercise your debugging skills.
-Also, there is no @code{with-no-warnings} macro---instead of
-suppressing compiler warnings, fix your code to avoid them!
-
-@item
-The function @code{unsafep} has been removed.
-
-@item
-File local variables can now specify a string with text properties.
-Since arbitrary Lisp expressions can be embedded in text properties,
-this can provide you with a great deal of flexibility and power. On
-the other hand, @code{safe-local-eval-forms} and the
-@code{safe-local-eval-function} function property have no special
-meaning.
-
-@item
-You can no longer use @code{char-displayable-p} to test if Emacs can
-display a certain character.
-
-@item
-The function @code{string-to-multibyte} is no longer available.
-
-@item
-The @code{translation-table-for-input} translation table has been
-removed. Also, translation hash tables are no longer available, so we
-don't need the functions @code{lookup-character} and
-@code{lookup-integer}.
-
-@item
-The @code{table} argument to @code{translate-region} can no longer be
-a char-table; it has to be a string.
-
-@item
-The variable @code{auto-coding-functions} and the two functions
-@code{merge-coding-systems} and @code{decode-coding-inserted-region}
-have been deleted. The coding system property
-@code{mime-text-unsuitable} no longer has any special meaning.
-
-@item
-If pure storage overflows while dumping, Emacs won't tell you how much
-additional pure storage it needs. Try adding in increments of 20000,
-until you have enough.
-
-@item
-The variables @code{gc-elapsed}, @code{gcs-done}, and
-@code{post-gc-hook} have been garbage-collected.
-@end itemize
-
-@ignore
- arch-tag: 1d0ef137-2bad-430e-ae8e-d820d569b5a6
-@end ignore
+@c -*-texinfo-*-
+@c This is part of the GNU Emacs Lisp Reference Manual.
+@c Copyright (C) 1999, 2002-2012 Free Software Foundation, Inc.
+@c See the file elisp.texi for copying conditions.
+
+@c This node must have no pointers.
+
+@node Antinews, GNU Free Documentation License, Packaging, Top
+@appendix Emacs 23 Antinews
+@c Update the elisp.texi Antinews menu entry with the above version number.
+
+For those users who live backwards in time, here is information about
+downgrading to Emacs version 23.4. We hope you will enjoy the greater
+simplicity that results from the absence of many Emacs @value{EMACSVER}
+features.
+
+@section Old Lisp Features in Emacs 23
+
+@itemize @bullet
+@item
+Support for lexical scoping has been removed; all variables are
+dynamically scoped. The @code{lexical-binding} variable has been
+removed, and so has the @var{lexical} argument to @code{eval}. The
+@code{defvar} and @code{defconst} forms no longer mark variables as
+dynamic, since all variables are dynamic.
+
+Having only dynamic binding follows the spirit of Emacs extensibility,
+for it allows any Emacs code to access any defined variable with a
+minimum of fuss. But @xref{Dynamic Binding Tips}, for tips to avoid
+making your programs hard to understand.
+
+@item
+Calling a minor mode function from Lisp with a nil or omitted argument
+does not enable the minor mode unconditionally; instead, it toggles
+the minor mode---which is the straightforward thing to do, since that
+is the behavior when invoked interactively. One downside is that it
+is more troublesome to enable minor modes from hooks; you have to do
+something like
+
+@example
+(add-hook 'foo-hook (lambda () (bar-mode 1)))
+@end example
+
+@noindent
+or define @code{turn-on-bar-mode} and call that from the hook.
+
+@item
+The @code{prog-mode} dummy major mode has been removed. Instead of
+using it as a crutch to meet programming mode conventions, you should
+explicitly ensure that your mode follows those conventions.
+@xref{Major Mode Conventions}.
+
+@item
+Emacs no longer supports bidirectional display and editing. Since
+there is no need to worry about the insertion of right-to-left text
+messing up how lines and paragraphs are displayed, the function
+@code{bidi-string-mark-left-to-right} has been removed; so have many
+other functions and variables related to bidirectional display.
+Unicode directionality characters like @code{U+200E} ("left-to-right
+mark") have no special effect on display.
+
+@item
+Emacs windows now have most of their internal state hidden from Lisp.
+Internal windows are no longer visible to Lisp; functions such as
+@code{window-parent}, window parameters related to window arrangement,
+and window-local buffer lists have all been removed. Functions for
+resizing windows can delete windows if they become too small.
+
+The ``action function'' feature for controlling buffer display has
+been removed, including @code{display-buffer-overriding-action} and
+related variables, as well as the @var{action} argument to
+@code{display-buffer} and other functions. The way to
+programmatically control how Emacs chooses a window to display a
+buffer is to bind the right combination of
+@code{special-display-regexps}, @code{pop-up-frames}, and other
+variables.
+
+@item
+The standard completion interface has been simplified, eliminating the
+@code{completion-extra-properties} variable, the @code{metadata}
+action flag for completion functions, and the concept of
+``completion categories''. Lisp programmers may now find the choice
+of methods for tuning completion less bewildering, but if a package
+finds the streamlined interface insufficient for its needs, it must
+implement its own specialized completion feature.
+
+@item
+@code{copy-directory} now behaves the same whether or not the
+destination is an existing directory: if the destination exists, the
+@emph{contents} of the first directory are copied into it (with
+subdirectories handled recursively), rather than copying the first
+directory into a subdirectory.
+
+@item
+The @var{trash} arguments for @code{delete-file} and
+@code{delete-directory} have been removed. The variable
+@code{delete-by-moving-to-trash} must now be used with care; whenever
+it is non-@code{nil}, all calls to @code{delete-file} or
+@code{delete-directory} use the trash.
+
+@item
+Because Emacs no longer supports SELinux file contexts, the
+@var{preserve-selinux-context} argument to @code{copy-file} has been
+removed. The return value of @code{backup-buffer} no longer has an
+entry for the SELinux file context.
+
+@item
+For mouse click input events in the text area, the Y pixel coordinate
+in the @var{position} list (@pxref{Click Events}) now counts from the
+top of the header line, if there is one, rather than the top of the
+text area.
+
+@item
+Bindings in menu keymaps (@pxref{Format of Keymaps}) now sometimes get
+an additional @var{cache} entry in their definitions, like this:
+
+@example
+(@var{type} @var{item-name} @var{cache} . @var{binding})
+@end example
+
+@noindent
+The @var{cache} entry is used internally by Emacs to record equivalent
+keyboard key sequences for invoking the same command; Lisp programs
+should never use it.
+@c Not really NEWS-worthy then...
+
+@item
+The @code{gnutls} library has been removed, and the function
+@code{open-network-stream} correspondingly simplified.
+Lisp programs that want an encrypted network connection must now call
+external utilities such as @command{starttls} or @command{gnutls-cli}.
+
+@item
+Tool bars can no longer display separators, which frees up several
+pixels of space on each graphical frame.
+
+@item
+As part of the ongoing quest for simplicity, many other functions and
+variables have been eliminated.
+@end itemize
HCoop / bpt / emacs.git / blobdiff