@c -*-texinfo-*-
@c This is part of the GNU Emacs Lisp Reference Manual.
-@c Copyright (C) 1990, 1991, 1992, 1993, 1994, 1995, 1998, 1999, 2003
-@c Free Software Foundation, Inc.
+@c Copyright (C) 1990, 1991, 1992, 1993, 1994, 1995, 1998, 1999,
+@c 2003, 2004, 2005 Free Software Foundation, Inc.
@c See the file elisp.texi for copying conditions.
@setfilename ../info/modes
@node Modes, Documentation, Keymaps, Top
* Imenu:: How a mode can provide a menu
of definitions in the buffer.
* Font Lock Mode:: How modes can highlight text according to syntax.
+* Desktop Save Mode:: How modes can have buffer state saved between
+ Emacs sessions.
* Hooks:: How to use hooks; how to write code that provides hooks.
@end menu
* Mode Help:: Finding out how to use a mode.
* Derived Modes:: Defining a new major mode based on another major
mode.
+* Mode Hooks:: Hooks run at the end of major mode functions.
@end menu
@node Major Mode Conventions
characters are reserved for minor modes, and ordinary letters are
reserved for users.
-It is reasonable for a major mode to rebind a key sequence with a
-standard meaning, if it implements a command that does ``the same job''
-in a way that fits the major mode better. For example, a major mode for
-editing a programming language might redefine @kbd{C-M-a} to ``move to
-the beginning of a function'' in a way that works better for that
-language.
-
-Major modes such as Dired or Rmail that do not allow self-insertion of
-text can reasonably redefine letters and other printing characters as
-editing commands. Dired and Rmail both do this.
+A major mode can also rebind the keys @kbd{M-n}, @kbd{M-p} and
+@kbd{M-s}. The bindings for @kbd{M-n} and @kbd{M-p} should normally
+be some kind of ``moving forward and backward,'' but this does not
+necessarily mean cursor motion.
+
+It is legitimate for a major mode to rebind a standard key sequence if
+it provides a command that does ``the same job'' in a way better
+suited to the text this mode is used for. For example, a major mode
+for editing a programming language might redefine @kbd{C-M-a} to
+``move to the beginning of a function'' in a way that works better for
+that language.
+
+It is also legitimate for a major mode to rebind a standard key
+sequence whose standard meaning is rarely useful in that mode. For
+instance, minibuffer modes rebind @kbd{M-r}, whose standard meaning is
+rarely of any use in the minibuffer. Major modes such as Dired or
+Rmail that do not allow self-insertion of text can reasonably redefine
+letters and other printing characters as special commands.
@item
Major modes must not define @key{RET} to do anything other than insert
@kbd{C-j}. Please keep this distinction uniform for all major modes.
@item
-Major modes should not alter options that are primary a matter of user
+Major modes should not alter options that are primarily a matter of user
preference, such as whether Auto-Fill mode is enabled. Leave this to
each user to decide. However, a major mode should customize other
variables so that Auto-Fill mode will work usefully @emph{if} the user
@item
@cindex abbrev tables in modes
The mode may have its own abbrev table or may share one with other
-related modes. If it has its own abbrev table, it should store this in
-a variable named @code{@var{modename}-mode-abbrev-table}. @xref{Abbrev
-Tables}.
+related modes. If it has its own abbrev table, it should store this
+in a variable named @code{@var{modename}-mode-abbrev-table}. If the
+major mode command defines any abbrevs itself, it should pass @code{t}
+for the @var{system-flag} argument to @code{define-abbrev}.
+@xref{Abbrev Tables}.
@item
The mode should specify how to do highlighting for Font Lock mode, by
Each major mode should have a @dfn{mode hook} named
@code{@var{modename}-mode-hook}. The major mode command should run that
hook, with @code{run-mode-hooks}, as the very last thing it
-does. @xref{Hooks}.
+does. @xref{Mode Hooks}.
@item
The major mode command may start by calling some other major mode
settings. A mode that does this is called a @dfn{derived mode}. The
recommended way to define one is to use @code{define-derived-mode},
but this is not required. Such a mode should use
-@code{delay-mode-hooks} around its entire body, including the call to
-the parent mode command and the final call to @code{run-mode-hooks}.
-(Using @code{define-derived-mode} does this automatically.)
+@code{delay-mode-hooks} around its entire body (including the call to
+the parent mode command) @emph{except} for the final call to
+@code{run-mode-hooks}, which runs the derived mode's hook. (Using
+@code{define-derived-mode} does this automatically.) @xref{Derived
+Modes}, and @ref{Mode Hooks}.
@item
If something special should be done if the user switches a buffer from
@end example
@noindent
-This tells Emacs that new buffers created while the current buffer is in
-Funny mode should not inherit Funny mode. Modes such as Dired, Rmail,
+This tells Emacs that new buffers created while the current buffer is
+in Funny mode should not inherit Funny mode, in case
+@code{default-major-mode} is @code{nil}. Modes such as Dired, Rmail,
and Buffer List use this feature.
@item
file that contains the mode definition. @xref{Auto Major Mode}.
@item
-In the documentation, you should provide a sample @code{autoload} form
-and an example of how to add to @code{auto-mode-alist}, that users can
-include in their init files (@pxref{Init File}).
+In the comments that document the file, you should provide a sample
+@code{autoload} form and an example of how to add to
+@code{auto-mode-alist}, that users can include in their init files
+(@pxref{Init File}).
@item
@cindex mode loading
@smallexample
@group
-;; @r{Create mode-specific tables.}
-(defvar text-mode-syntax-table nil
- "Syntax table used while in text mode.")
+;; @r{Create the syntax table for this mode.}
+(defvar text-mode-syntax-table
+ (let ((st (make-syntax-table)))
+ (modify-syntax-entry ?\" ". " st)
+ (modify-syntax-entry ?\\ ". " st)
+ ;; We add `p' so that M-c on 'hello' leads to 'Hello' rather than 'hello'.
+ (modify-syntax-entry ?' "w p" st)
+ st)
+ "Syntax table used while in `text-mode'.")
@end group
+;; @r{Create the keymap for this mode.}
@group
-(if text-mode-syntax-table
- () ; @r{Do not change the table if it is already set up.}
- (setq text-mode-syntax-table (make-syntax-table))
- (modify-syntax-entry ?\" ". " text-mode-syntax-table)
- (modify-syntax-entry ?\\ ". " text-mode-syntax-table)
- (modify-syntax-entry ?' "w " text-mode-syntax-table))
+(defvar text-mode-map
+ (let ((map (make-sparse-keymap)))
+ (define-key map "\e\t" 'ispell-complete-word)
+ (define-key map "\es" 'center-line)
+ (define-key map "\eS" 'center-paragraph)
+ map)
+ "Keymap for `text-mode'.
+Many other modes, such as `mail-mode', `outline-mode' and `indented-text-mode',
+inherit all the commands defined in this map.")
@end group
+@end smallexample
+
+ Here is how the actual mode command is defined now:
+@smallexample
@group
-(defvar text-mode-abbrev-table nil
- "Abbrev table used while in text mode.")
-(define-abbrev-table 'text-mode-abbrev-table ())
+(define-derived-mode text-mode nil "Text"
+ "Major mode for editing text written for humans to read.
+In this mode, paragraphs are delimited only by blank or white lines.
+You can thus get the full benefit of adaptive filling
+ (see the variable `adaptive-fill-mode').
+\\@{text-mode-map@}
+Turning on Text mode runs the normal hook `text-mode-hook'."
@end group
-
@group
-(defvar text-mode-map nil ; @r{Create a mode-specific keymap.}
- "Keymap for Text mode.
-Many other modes, such as Mail mode, Outline mode and Indented Text mode,
-inherit all the commands defined in this map.")
-
-(if text-mode-map
- () ; @r{Do not change the keymap if it is already set up.}
- (setq text-mode-map (make-sparse-keymap))
- (define-key text-mode-map "\e\t" 'ispell-complete-word)
- (define-key text-mode-map "\t" 'indent-relative)
- (define-key text-mode-map "\es" 'center-line)
- (define-key text-mode-map "\eS" 'center-paragraph))
+ (make-local-variable 'text-mode-variant)
+ (setq text-mode-variant t)
+ ;; @r{These two lines are a feature added recently.}
+ (set (make-local-variable 'require-final-newline)
+ mode-require-final-newline)
+ (set (make-local-variable 'indent-line-function) 'indent-relative))
@end group
@end smallexample
- This was formerly the complete major mode function definition for Text mode:
+ But here is how it was defined formerly, before
+@code{define-derived-mode} existed:
@smallexample
+@group
+;; @r{This isn't needed nowadays, since @code{define-derived-mode} does it.}
+(defvar text-mode-abbrev-table nil
+ "Abbrev table used while in text mode.")
+(define-abbrev-table 'text-mode-abbrev-table ())
+@end group
+
@group
(defun text-mode ()
"Major mode for editing text intended for humans to read...
(set-syntax-table text-mode-syntax-table)
@end group
@group
+ ;; @r{These four lines are absent from the current version}
+ ;; @r{not because this is done some other way, but rather}
+ ;; @r{because nowadays Text mode uses the normal definition of paragraphs.}
(make-local-variable 'paragraph-start)
(setq paragraph-start (concat "[ \t]*$\\|" page-delimiter))
(make-local-variable 'paragraph-separate)
@group
;; @r{Create mode-specific table variables.}
(defvar lisp-mode-syntax-table nil "")
-(defvar emacs-lisp-mode-syntax-table nil "")
(defvar lisp-mode-abbrev-table nil "")
@end group
@group
-(if (not emacs-lisp-mode-syntax-table) ; @r{Do not change the table}
- ; @r{if it is already set.}
+(defvar emacs-lisp-mode-syntax-table
+ (let ((table (make-syntax-table)))
(let ((i 0))
- (setq emacs-lisp-mode-syntax-table (make-syntax-table))
@end group
@group
- ;; @r{Set syntax of chars up to 0 to class of chars that are}
+ ;; @r{Set syntax of chars up to @samp{0} to say they are}
;; @r{part of symbol names but not words.}
- ;; @r{(The number 0 is @code{48} in the @sc{ascii} character set.)}
+ ;; @r{(The digit @samp{0} is @code{48} in the @acronym{ASCII} character set.)}
(while (< i ?0)
- (modify-syntax-entry i "_ " emacs-lisp-mode-syntax-table)
- (setq i (1+ i)))
- @dots{}
+ (modify-syntax-entry i "_ " table)
+ (setq i (1+ i)))
+ ;; @r{@dots{} similar code follows for other character ranges.}
@end group
@group
- ;; @r{Set the syntax for other characters.}
- (modify-syntax-entry ? " " emacs-lisp-mode-syntax-table)
- (modify-syntax-entry ?\t " " emacs-lisp-mode-syntax-table)
- @dots{}
+ ;; @r{Then set the syntax codes for characters that are special in Lisp.}
+ (modify-syntax-entry ? " " table)
+ (modify-syntax-entry ?\t " " table)
+ (modify-syntax-entry ?\f " " table)
+ (modify-syntax-entry ?\n "> " table)
+@end group
+@group
+ ;; @r{Give CR the same syntax as newline, for selective-display.}
+ (modify-syntax-entry ?\^m "> " table)
+ (modify-syntax-entry ?\; "< " table)
+ (modify-syntax-entry ?` "' " table)
+ (modify-syntax-entry ?' "' " table)
+ (modify-syntax-entry ?, "' " table)
+@end group
+@group
+ ;; @r{@dots{}likewise for many other characters@dots{}}
+ (modify-syntax-entry ?\( "() " table)
+ (modify-syntax-entry ?\) ")( " table)
+ (modify-syntax-entry ?\[ "(] " table)
+ (modify-syntax-entry ?\] ")[ " table))
+ table))
@end group
@group
- (modify-syntax-entry ?\( "() " emacs-lisp-mode-syntax-table)
- (modify-syntax-entry ?\) ")( " emacs-lisp-mode-syntax-table)
- @dots{}))
;; @r{Create an abbrev table for lisp-mode.}
(define-abbrev-table 'lisp-mode-abbrev-table ())
@end group
@smallexample
@group
(defun lisp-mode-variables (lisp-syntax)
- (cond (lisp-syntax
- (set-syntax-table lisp-mode-syntax-table)))
+ (when lisp-syntax
+ (set-syntax-table lisp-mode-syntax-table))
(setq local-abbrev-table lisp-mode-abbrev-table)
@dots{}
@end group
(defvar shared-lisp-mode-map ()
"Keymap for commands shared by all sorts of Lisp modes.")
+;; @r{Putting this @code{if} after the @code{defvar} is an older style.}
(if shared-lisp-mode-map
()
(setq shared-lisp-mode-map (make-sparse-keymap))
; @r{finds out what to describe.}
(setq mode-name "Lisp") ; @r{This goes into the mode line.}
(lisp-mode-variables t) ; @r{This defines various variables.}
+ (make-local-variable 'comment-start-skip)
+ (setq comment-start-skip
+ "\\(\\(^\\|[^\\\\\n]\\)\\(\\\\\\\\\\)*\\)\\(;+\\|#|\\) *")
+ (make-local-variable 'font-lock-keywords-case-fold-search)
+ (setq font-lock-keywords-case-fold-search t)
@end group
@group
(setq imenu-case-fold-search t)
in particular. Other major modes are defined in effect by comparison
with this one---their definitions say what to change, starting from
Fundamental mode. The @code{fundamental-mode} function does @emph{not}
-run any hooks; you're not supposed to customize it. (If you want Emacs
+run any mode hooks; you're not supposed to customize it. (If you want Emacs
to behave differently in Fundamental mode, change the @emph{global}
state of Emacs.)
@end deffn
@code{define-derived-mode} does that automatically.
@end defmac
+@node Mode Hooks
+@subsection Mode Hooks
+
+The two last things a major mode function does is to run its mode
+hook and finally the mode independent normal hook
+@code{after-change-major-mode-hook}. If the major mode is a derived
+mode, that is if it calls another major mode (the parent mode) in its
+body, then the parent's mode hook is run just before the derived
+mode's hook. Neither the parent's mode hook nor
+@code{after-change-major-mode-hook} are run at the end of the actual
+call to the parent mode. This applies recursively if the parent mode
+has itself a parent. That is, the mode hooks of all major modes called
+directly or indirectly by the major mode function are all run in
+sequence at the end, just before @code{after-change-major-mode-hook}.
+
+If you are customizing a major mode, rather than defining one, the
+above is all you need to know about the hooks run at the end of a
+major mode. This also applies if you use @code{define-derived-mode}
+to define a major mode, because that macro will automatically
+implement the above for you.
+
+Programmers wishing to define a major mode without using
+@code{define-derived-mode}, should make sure that their major mode
+follows the above conventions. @xref{Major Mode Conventions}, for how
+this should be accomplished. Below, we give some implementation
+details.
+
+@defun run-mode-hooks &rest hookvars
+Major modes should run their mode hook using this function. It is
+similar to @code{run-hooks} (@pxref{Hooks}), but if run inside a
+@code{delay-mode-hooks} form, this function does not run any hooks.
+Instead, it arranges for @var{hookvars} to be run at a later call to
+the function. Otherwise, @code{run-mode-hooks} runs any delayed hooks
+in order, then @var{hookvars} and finally
+@code{after-change-major-mode-hook}.
+@end defun
+
+@defmac delay-mode-hooks body...
+This macro executes @var{body} like @code{progn}, but all calls to
+@code{run-mode-hooks} inside @var{body} delay running their hooks.
+They will be run by the first call to @code{run-mode-hooks} after exit
+from @code{delay-mode-hooks}.
+@end defmac
+
+@defvar after-change-major-mode-hook
+Every major mode function should run this normal hook at its very end.
+It normally does not need to do so explicitly. Indeed, a major mode
+function should normally run its mode hook with @code{run-mode-hooks}
+as the very last thing it does and @code{run-mode-hooks} runs
+@code{after-change-major-mode-hook} at its very end.
+@end defvar
+
@node Minor Modes
@section Minor Modes
@cindex minor mode
other tables.
In addition, there are several conventions that are specific to
-minor modes.
+minor modes. (The easiest way to follow all the conventions is to use
+the macro @code{define-minor-mode}; @ref{Defining Minor Modes}.)
@itemize @bullet
@item
off if it is on). It should turn the mode on if the argument is a
positive integer, the symbol @code{t}, or a list whose @sc{car} is one
of those. It should turn the mode off if the argument is a negative
-integer or zero, the symbol @code{-}, or a list whose @sc{car} is one
-of those. The meaning of other arguments is not specified.
+integer or zero, the symbol @code{-}, or a list whose @sc{car} is a
+negative integer or zero. The meaning of other arguments is not
+specified.
Here is an example taken from the definition of @code{transient-mark-mode}.
It shows the use of @code{transient-mark-mode} as a variable that enables or
If just setting the variable is not sufficient to enable the mode, you
should also specify a @code{:set} method which enables the mode by
-invoke the mode command. Note in the variable's documentation string that
+invoking the mode command. Note in the variable's documentation string that
setting the variable other than via Custom may not take effect.
Also mark the definition with an autoload cookie (@pxref{Autoload}),
@subsection Defining Minor Modes
The macro @code{define-minor-mode} offers a convenient way of
-implementing a mode in one self-contained definition. It supports only
-buffer-local minor modes, not global ones.
+implementing a mode in one self-contained definition.
-@defmac define-minor-mode mode doc [init-value [lighter [keymap keyword-args... body...]]]
+@defmac define-minor-mode mode doc [init-value [lighter [keymap]]] keyword-args... body...
@tindex define-minor-mode
This macro defines a new minor mode whose name is @var{mode} (a
symbol). It defines a command named @var{mode} to toggle the minor
(@var{key-sequence} . @var{definition})
@end example
-The @var{keyword-args} consist of keywords followed by corresponding
-values. A few keywords have special meanings:
+The above three arguments @var{init-value}, @var{lighter}, and
+@var{keymap} can be (partially) omitted when @var{keyword-args} are
+used. The @var{keyword-args} consist of keywords followed by
+corresponding values. A few keywords have special meanings:
@table @code
@item :global @var{global}
;; The indicator for the mode line.
" Hungry"
;; The minor mode bindings.
- '(("\C-\^?" . hungry-electric-delete)
- ("\C-\M-\^?"
- . (lambda ()
- (interactive)
- (hungry-electric-delete t))))
+ '(("\C-\^?" . hungry-electric-delete))
:group 'hunger)
@end smallexample
@code{hungry-mode} to toggle it, a variable named @code{hungry-mode}
which indicates whether the mode is enabled, and a variable named
@code{hungry-mode-map} which holds the keymap that is active when the
-mode is enabled. It initializes the keymap with key bindings for
-@kbd{C-@key{DEL}} and @kbd{C-M-@key{DEL}}. It puts the variable
-@code{hungry-mode} into custom group @code{hunger}. There are no
-@var{body} forms---many minor modes don't need any.
+mode is enabled. It initializes the keymap with a key binding for
+@kbd{C-@key{DEL}}. It puts the variable @code{hungry-mode} into
+custom group @code{hunger}. There are no @var{body} forms---many
+minor modes don't need any.
Here's an equivalent way to write it:
display it in the new way.
@c Emacs 19 feature
-@defun force-mode-line-update
+@defun force-mode-line-update &optional all
Force redisplay of the current buffer's mode line and header line.
The next redisplay will update the mode line and header line based on
-the latest values of all relevant variables.
+the latest values of all relevant variables. With optional
+non-@code{nil} @var{all}, force redisplay of all mode lines and header
+lines.
This function also forces recomputation of the menu bar menus
and the frame title.
@end defun
- The mode line is usually displayed in inverse video; see
-@code{mode-line-inverse-video} in @ref{Inverse Video}.
+ The selected window's mode line is usually displayed in a different
+color using the face @code{mode-line}. Other windows' mode lines
+appear in the face @code{mode-line-inactive} instead. @xref{Faces}.
A window that is just one line tall does not display either a mode
line or a header line, even if the variables call for one. A window
process the mode-line construct @var{elt} recursively and add the text
properties specified by @var{props} to the result. The argument
@var{props} should consist of zero or more pairs @var{text-property}
-@var{value}. (This feature is new as of Emacs 21.4.)
-@c FIXME: This might be Emacs 21.5.
+@var{value}. (This feature is new as of Emacs 22.1.)
@item (@var{symbol} @var{then} @var{else})
A list whose first element is a symbol that is not a keyword specifies a
@end defvar
@defvar global-mode-string
-This variable holds a mode-line spec that appears in the mode line by
-default, just after the buffer name. The command @code{display-time}
+This variable holds a mode-line spec that, by default, appears in the
+mode line just after the @code{which-func-mode} minor mode if set,
+else after @code{mode-line-modes}. The command @code{display-time}
sets @code{global-mode-string} to refer to the variable
-@code{display-time-string}, which holds a string containing the time and
-load information.
+@code{display-time-string}, which holds a string containing the time
+and load information.
The @samp{%M} construct substitutes the value of
@code{global-mode-string}, but that is obsolete, since the variable is
effect, since it is impossible to move point into the mode line. This
keymap can only take real effect for mouse clicks.
+ When the mode line refers to a variable which does not have a
+non-@code{nil} @code{risky-local-variable} property, any text
+properties given or specified within that variable's values are
+ignored. This is because such properties could otherwise specify
+functions to be called, and those functions could come from file
+local variables.
+
@node Header Lines
@subsection Window Header Lines
@cindex header line (of a window)
the text that would appear in a mode line or header line
based on certain mode-line specification.
-@defun format-mode-line &optional format window no-props
+@defun format-mode-line format &optional face window buffer
This function formats a line of text according to @var{format} as if
it were generating the mode line for @var{window}, but instead of
displaying the text in the mode line or the header line, it returns
-the text as a string.
-
-If @var{format} is @code{nil}, that means to use
-@code{mode-line-format} and return the text that would appear in the
-mode line. If @var{format} is @code{t}, that means to use
-@code{header-line-format} so as to return the text that would appear
-in the header line (@code{""} if the window has no header line).
-The argument @var{window} defaults to the selected window.
+the text as a string. The argument @var{window} defaults to the
+selected window. If @var{buffer} is non-@code{nil}, all the
+information used is taken from @var{buffer}; by default, it comes from
+@var{window}'s buffer.
The value string normally has text properties that correspond to the
-faces, keymaps, etc., that the mode line would have. If
-@var{no-props} is non-@code{nil}, the value has no text properties.
+faces, keymaps, etc., that the mode line would have. And any character
+for which no @code{face} property is specified gets a default
+value which is usually @var{face}. (If @var{face} is @code{t},
+that stands for either @code{mode-line} if @var{window} is selected,
+otherwise @code{mode-line-inactive}.)
+
+However, if @var{face} is an integer, the value has no text properties.
+
+For example, @code{(format-mode-line header-line-format)} returns the
+text that would appear in the selected window's header line (@code{""}
+if it has no header line). @code{(format-mode-line header-line-format
+'header-line)} returns the same text, with each character
+carrying the face that it will have in the header line itself.
@end defun
@node Imenu
directly to that location in the buffer. Imenu works by constructing
a buffer index which lists the names and buffer positions of the
definitions, or other named portions of the buffer; then the user can
-choose one of them and move point to it. The user-level commands for
-using Imenu are described in the Emacs Manual (@pxref{Imenu,, Imenu,
-emacs, the Emacs Manual}). This section explains how to customize
-Imenu's method of finding definitions or buffer portions for a
-particular major mode.
+choose one of them and move point to it. Major modes can add a menu
+bar item to use Imenu using @code{imenu-add-to-menubar}.
+
+@defun imenu-add-to-menubar name
+This function defines a local menu bar item named @var{name}
+to run Imenu.
+@end defun
+
+ The user-level commands for using Imenu are described in the Emacs
+Manual (@pxref{Imenu,, Imenu, emacs, the Emacs Manual}). This section
+explains how to customize Imenu's method of finding definitions or
+buffer portions for a particular major mode.
The usual and simplest way is to set the variable
@code{imenu-generic-expression}:
(@pxref{Faces for Font Lock}). Search-based fontification follows.
@menu
-* Font Lock Basics::
-* Search-based Fontification::
-* Other Font Lock Variables::
-* Levels of Font Lock::
-* Precalculated Fontification::
-* Faces for Font Lock::
-* Syntactic Font Lock::
+* Font Lock Basics:: Overview of customizing Font Lock.
+* Search-based Fontification:: Fontification based on regexps.
+* Other Font Lock Variables:: Additional customization facilities.
+* Levels of Font Lock:: Each mode can define alternative levels
+ so that the user can select more or less.
+* Precalculated Fontification:: How Lisp programs that produce the buffer
+ contents can also specify how to fontify it.
+* Faces for Font Lock:: Special faces specifically for Font Lock.
+* Syntactic Font Lock:: Defining character syntax based on context
+ using the Font Lock mechanism.
@end menu
@node Font Lock Basics
syntactic fontification (of strings and comments) is not performed.
The third element, @var{case-fold}, specifies the value of
-@code{font-lock-case-fold-search}. If it is non-@code{nil}, Font Lock
+@code{font-lock-keywords-case-fold-search}. If it is non-@code{nil}, Font Lock
mode ignores case when searching as directed by
@code{font-lock-keywords}.
it finds using @code{font-lock-keyword-face}.
When @var{function} is called, it receives one argument, the limit of
-the search; it should searching at point, and not search beyond the
+the search; it should begin searching at point, and not search beyond the
limit. It should return non-@code{nil} if it succeeds, and set the
match data to describe the match that was found. Returning @code{nil}
indicates failure of the search.
@var{matcher}, then you can use @code{regexp-opt-depth} (@pxref{Syntax
of Regexps}) to calculate the value for @var{match}.
-@item (@var{matcher} . @var{facename})
-In this kind of element, @var{facename} is an expression whose value
-specifies the face name to use for highlighting.
+@item (@var{matcher} . @var{facespec})
+In this kind of element, @var{facespec} is an object which specifies
+the face variable to use for highlighting. In the simplest case, it
+is a Lisp variable (a symbol), whose value should be a face name.
@example
;; @r{Highlight occurrences of @samp{fubar},}
("fubar" . fubar-face)
@end example
-The value of @var{facename} is usually a face name (a symbol), but it
-can also be a list of the form
+However, @var{facespec} can also be a list of the form
@example
(face @var{face} @var{prop1} @var{val1} @var{prop2} @var{val2}@dots{})
It has the form
@example
-(@var{subexp} @var{facename} @var{override} @var{laxmatch})
+(@var{subexp} @var{facespec} @var{override} @var{laxmatch})
@end example
The @sc{car}, @var{subexp}, is an integer specifying which subexpression
of the match to fontify (0 means the entire matching text). The second
-subelement, @var{facename}, specifies the face, as described above.
+subelement, @var{facespec}, specifies the face, as described above.
The last two values in @var{highlighter}, @var{override} and
@var{laxmatch}, are flags. If @var{override} is @code{t}, this
element can override existing fontification made by previous elements
of @code{font-lock-keywords}. If it is @code{keep}, then each
character is fontified if it has not been fontified already by some
-other element. If it is @code{prepend}, the face @var{facename} is
-added to the beginning of the @code{font-lock-face} property. If it
-is @code{append}, the face @var{facename} is added to the end of the
+other element. If it is @code{prepend}, the face specified by
+@var{facespec} is added to the beginning of the @code{font-lock-face}
+property. If it is @code{append}, the face is added to the end of the
@code{font-lock-face} property.
If @var{laxmatch} is non-@code{nil}, it means there should be no error
Obviously, fontification of the subexpression numbered @var{subexp} will
not occur. However, fontification of other subexpressions (and other
regexps) will continue. If @var{laxmatch} is @code{nil}, and the
-specified subexpression is missing, then an error is signalled which
+specified subexpression is missing, then an error is signaled which
terminates search-based fontification.
Here are some examples of elements of this kind, and what they do:
to match text which spans lines; this does not work reliably. While
@code{font-lock-fontify-buffer} handles multi-line patterns correctly,
updating when you edit the buffer does not, since it considers text one
-line at a time.
+line at a time. If you have patterns that typically only span one
+line but can occasionally span two or three, such as
+@samp{<title>...</title>}, you can ask font-lock to be more careful by
+setting @code{font-lock-multiline} to @code{t}. But it still will not
+work in all cases.
@node Other Font Lock Variables
@subsection Other Font Lock Variables
Additional properties (other than @code{font-lock-face}) that are
being managed by Font Lock mode. Font Lock mode normally manages only
the @code{font-lock-face} property; if you want it to manage others as
-well, you must specify them in a @var{facename} in
+well, you must specify them in a @var{facespec} in
@code{font-lock-keywords} as well as adding them to this list.
@end defvar
+@defvar font-lock-syntactic-face-function
+A function to determine which face to use for a given syntactic
+element (a string or a comment). The function is called with one
+argument, the parse state at point returned by
+@code{parse-partial-sexp}, and should return a face. The default
+value returns @code{font-lock-comment-face} for comments and
+@code{font-lock-string-face} for strings.
+
+This can be used to highlighting different kinds of strings or
+comments differently. It is also sometimes abused together with
+@code{font-lock-syntactic-keywords} to highlight elements that span
+multiple lines, but this is too obscure to document in this manual.
+@end defvar
+
@node Levels of Font Lock
@subsection Levels of Font Lock
@node Precalculated Fontification
@subsection Precalculated Fontification
-In addition to using @code{font-lock-defaults} for search-based
+ In addition to using @code{font-lock-defaults} for search-based
fontification, you may use the special character property
@code{font-lock-face} (@pxref{Special Properties}). This property
acts just like the explicit @code{face} property, but its activation
@vindex font-lock-comment-face
Used (typically) for comments.
+@item font-lock-doc-face
+@vindex font-lock-doc-face
+Used (typically) for documentation strings in the code.
+
@item font-lock-string-face
@vindex font-lock-string-face
Used (typically) for string constants.
@end defvar
+@node Desktop Save Mode
+@section Desktop Save Mode
+@cindex desktop save mode
+
+@dfn{Desktop Save Mode} is a feature to save the state of Emacs from
+one session to another. The user-level commands for using Desktop
+Save Mode are described in the GNU Emacs Manual (@pxref{Saving Emacs
+Sessions,,, emacs, the GNU Emacs Manual}). Modes whose buffers visit
+a file, don't have to do anything to use this feature.
+
+For buffers not visiting a file to have their state saved, the major
+mode must bind the buffer local variable @code{desktop-save-buffer} to
+a non-@code{nil} value.
+
+@defvar desktop-save-buffer
+If this buffer-local variable is non-@code{nil}, the buffer will have
+its state saved in the desktop file at desktop save. If the value is
+a function, it is called at desktop save with argument
+@var{desktop-dirname}, and its value is saved in the desktop file along
+with the state of the buffer for which it was called. When file names
+are returned as part of the auxiliary information, they should be
+formatted using the call
+
+@example
+(desktop-file-name @var{file-name} @var{desktop-dirname})
+@end example
+
+@end defvar
+
+For buffers not visiting a file to be restored, the major mode must
+define a function to do the job, and that function must be listed in
+the alist @code{desktop-buffer-mode-handlers}.
+
+@defvar desktop-buffer-mode-handlers
+Alist with elements
+
+@example
+(@var{major-mode} . @var{restore-buffer-function})
+@end example
+
+The function @var{restore-buffer-function} will be called with
+argument list
+
+@example
+(@var{buffer-file-name} @var{buffer-name} @var{desktop-buffer-misc})
+@end example
+
+and it should return the restored buffer.
+Here @var{desktop-buffer-misc} is the value returned by the function
+optionally bound to @code{desktop-save-buffer}.
+
+@end defvar
+
@node Hooks
@section Hooks
@cindex hooks
a symbol with a function definition), it is called. If it is a list
that isn't a function, its elements are called, consecutively. All
the hook functions are called with no arguments.
-
-For example, here's how @code{emacs-lisp-mode} runs its mode hook:
-
-@example
-(run-hooks 'emacs-lisp-mode-hook)
-@end example
@end defun
-@defun run-mode-hooks &rest hookvars
-Like @code{run-hooks}, but is affected by the @code{delay-mode-hooks}
-macro.
-@end defun
-
-@defmac delay-mode-hooks body...
-This macro executes the @var{body} forms but defers all calls to
-@code{run-mode-hooks} within them until the end of @var{body}.
-This macro enables a derived mode to arrange not to run
-its parent modes' mode hooks until the end.
-@end defmac
-
@defun run-hook-with-args hook &rest args
This function is the way to run an abnormal hook and always call all
of the hook functions. It calls each of the hook functions one by
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