;;; font-core.el --- Core interface to font-lock
;; Copyright (C) 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000, 2001,
-;; 2002, 2003, 2005 Free Software Foundation, Inc.
+;; 2002, 2003, 2004, 2005, 2006 Free Software Foundation, Inc.
;; Maintainer: FSF
;; Keywords: languages, faces
;; You should have received a copy of the GNU General Public License
;; along with GNU Emacs; see the file COPYING. If not, write to the
-;; Free Software Foundation, Inc., 59 Temple Place - Suite 330,
-;; Boston, MA 02111-1307, USA.
+;; Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
+;; Boston, MA 02110-1301, USA.
;;; Code:
settings. See the variable `font-lock-defaults', which takes precedence.")
(make-obsolete-variable 'font-lock-defaults-alist 'font-lock-defaults)
+(defvar font-lock-extend-region-function nil
+ "A function that determines the region to fontify after a change.
+
+This buffer-local variable is either nil, or is a function that determines the
+region to fontify. It is usually set by the major mode. The currently active
+font-lock after-change function calls this function after each buffer change.
+
+The function is given three parameters, the standard BEG, END, and OLD-LEN
+from after-change-functions. It should return either a cons of the beginning
+and end buffer positions \(in that order) of the region to fontify, or nil
+\(which directs the caller to fontify a default region). This function need
+not preserve point or the match-data, but must preserve the current
+restriction. The region it returns may start or end in the middle of a
+line.")
+(make-variable-buffer-local 'font-lock-extend-region-function)
+
+(defun font-lock-extend-region (beg end old-len)
+ "Determine the region to fontify after a buffer change.
+
+BEG END and OLD-LEN are the standard parameters from after-change-functions.
+The return value is either nil \(which directs the caller to chose the region
+itself), or a cons of the beginning and end \(in that order) of the region.
+The region returned may start or end in the middle of a line."
+ (if font-lock-extend-region-function
+ (save-match-data
+ (save-excursion
+ (funcall font-lock-extend-region-function beg end old-len)))))
+
(defvar font-lock-function 'font-lock-default-function
"A function which is called when `font-lock-mode' is toggled.
It will be passed one argument, which is the current value of
`font-lock-mode'.")
+;; The mode for which font-lock was initialized, or nil if none.
+(defvar font-lock-mode-major-mode)
(define-minor-mode font-lock-mode
"Toggle Font Lock mode.
With arg, turn Font Lock mode off if and only if arg is a non-positive
(global-font-lock-mode t)
-There are a number of support modes that may be used to speed up Font Lock mode
-in various ways, specified via the variable `font-lock-support-mode'. Where
-major modes support different levels of fontification, you can use the variable
-`font-lock-maximum-decoration' to specify which level you generally prefer.
-When you turn Font Lock mode on/off the buffer is fontified/defontified, though
-fontification occurs only if the buffer is less than `font-lock-maximum-size'.
+Where major modes support different levels of fontification, you can use
+the variable `font-lock-maximum-decoration' to specify which level you
+generally prefer. When you turn Font Lock mode on/off the buffer is
+fontified/defontified, though fontification occurs only if the buffer is
+less than `font-lock-maximum-size'.
-For example, to specify that Font Lock mode use use Lazy Lock mode as a support
-mode and use maximum levels of fontification, put in your ~/.emacs:
+For example, to use maximum levels of fontification, put in your ~/.emacs:
- (setq font-lock-support-mode 'lazy-lock-mode)
(setq font-lock-maximum-decoration t)
To add your own highlighting for some major mode, and modify the highlighting
The above is the default behavior of `font-lock-mode'; you may specify
your own function which is called when `font-lock-mode' is toggled via
`font-lock-function'. "
- :group 'font-lock
+ nil nil nil
;; Don't turn on Font Lock mode if we don't have a display (we're running a
;; batch job) or if the buffer is invisible (the name starts with a space).
(when (or noninteractive (eq (aref (buffer-name) 0) ?\ ))
;; Arrange to unfontify this buffer if we change major mode later.
(if font-lock-mode
(add-hook 'change-major-mode-hook 'font-lock-change-mode nil t)
- (remove-hook 'change-major-mode-hook 'font-lock-change-mode t)))
+ (remove-hook 'change-major-mode-hook 'font-lock-change-mode t))
+ (when font-lock-mode
+ (setq font-lock-mode-major-mode major-mode)))
;; Get rid of fontification for the old major mode.
;; We do this when changing major modes.
'(font-lock-face)))
(restore-buffer-modified-p modp)))
+(defvar font-lock-set-defaults)
(defun font-lock-default-function (mode)
;; Turn on Font Lock mode.
(when mode
;; Only do hard work if the mode has specified stuff in
;; `font-lock-defaults'.
(when (or font-lock-defaults
- (and (boundp 'font-lock-keywords) font-lock-keywords)
+ (if (boundp 'font-lock-keywords) font-lock-keywords)
(with-no-warnings
- (cdr (assq major-mode font-lock-defaults-alist))))
+ (cdr (assq major-mode font-lock-defaults-alist)))
+ (and mode
+ (boundp 'font-lock-set-defaults)
+ font-lock-set-defaults
+ font-lock-mode-major-mode
+ (not (eq font-lock-mode-major-mode major-mode))))
(font-lock-mode-internal mode)))
(defun turn-on-font-lock ()
;; hook is run, the major mode is in the process of being changed and we do not
;; know what the final major mode will be. So, `font-lock-change-major-mode'
;; only (a) notes the name of the current buffer, and (b) adds our function
-;; `turn-on-font-lock-if-enabled' to the hook variables `find-file-hook' and
-;; `post-command-hook' (for buffers that are not visiting files). By the time
+;; `turn-on-font-lock-if-enabled' to the hook variables
+;; `after-change-major-mode-hook' and `post-command-hook' (for modes
+;; that do not yet run `after-change-major-mode-hook'). By the time
;; the functions on the first of these hooks to be run are run, the new major
;; mode is assumed to be in place. This way we get a Font Lock function run
;; when a major mode is turned on, without knowing major modes or their hooks.
;;
-;; Naturally this requires that (a) major modes run `kill-all-local-variables',
-;; as they are supposed to do, and (b) the major mode is in place after the
-;; file is visited or the command that ran `kill-all-local-variables' has
-;; finished, whichever the sooner. Arguably, any major mode that does not
-;; follow the convension (a) is broken, and I can't think of any reason why (b)
-;; would not be met (except `gnudoit' on non-files). However, it is not clean.
-;;
-;; Probably the cleanest solution is to have each major mode function run some
-;; hook, e.g., `major-mode-hook', but maybe implementing that change is
-;; impractical. I am personally against making `setq' a macro or be advised,
-;; or have a special function such as `set-major-mode', but maybe someone can
-;; come up with another solution?
+;; Naturally this requires that major modes run `kill-all-local-variables'
+;; and `after-change-major-mode-hook', as they are supposed to. For modes
+;; that do not run `after-change-major-mode-hook' yet, `post-command-hook'
+;; takes care of things if the mode is set directly or indirectly by
+;; an interactive command; however, problems can occur if the mode is
+;; set by a timer or process: in that case, proper handling of Font Lock mode
+;; may be delayed until the next interactive command.
;; User interface.
;;
(let (inhibit-quit)
(turn-on-font-lock))))
-(easy-mmode-define-global-mode
- global-font-lock-mode font-lock-mode turn-on-font-lock-if-enabled
- :extra-args (dummy))
+(define-global-minor-mode global-font-lock-mode
+ font-lock-mode turn-on-font-lock-if-enabled
+ :extra-args (dummy)
+ :initialize 'custom-initialize-safe-default
+ :init-value (not (or noninteractive emacs-basic-display))
+ :group 'font-lock
+ :version "22.1")
;;; End of Global Font Lock mode.