* font-lock.el (font-lock-refresh-defaults): New function, which

	can be used to let font-lock react to external changes in
	variables like font-lock-defaults and keywords.
	See http://thread.gmane.org/gmane.emacs.devel/118777/focus=118802

2 files changed, 24 insertions, 0 deletions

diff --git a/lisp/ChangeLog b/lisp/ChangeLog
index a454f132733..236f2fe35ad 100644
--- a/lisp/ChangeLog
+++ b/lisp/ChangeLog
@@ -1,3 +1,10 @@
+2009-12-28  Tassilo Horn  <tassilo@member.fsf.org>
+
+        * font-lock.el (font-lock-refresh-defaults): New function, which
+        can be used to let font-lock react to external changes in
+        variables like font-lock-defaults and keywords.
+        See http://thread.gmane.org/gmane.emacs.devel/118777/focus=118802
+
 2009-12-28  Dan Nicolaescu  <dann@ics.uci.edu>
 
         * vc-rcs.el (vc-rcs-register): Fix registering a specific version.
diff --git a/lisp/font-lock.el b/lisp/font-lock.el
index 95d061b3024..c2fd86ed726 100644
--- a/lisp/font-lock.el
+++ b/lisp/font-lock.el
@@ -1767,6 +1767,23 @@ A LEVEL of nil is equal to a LEVEL of 0, a LEVEL of t is equal to
 
 (defvar font-lock-set-defaults nil)     ; Whether we have set up defaults.
 
+(defun font-lock-refresh-defaults ()
+  "Restart fontification in current buffer after recomputing from defaults.
+Recompute fontification variables using `font-lock-defaults' (or,
+if nil, using `font-lock-defaults-alist') and
+`font-lock-maximum-decoration'.  Then restart fontification.
+
+Use this function when you have changed any of the above
+variables directly.
+
+Note: This function will erase modifications done by
+`font-lock-add-keywords' or `font-lock-remove-keywords', but will
+preserve `hi-lock-mode' highlighting patterns."
+  (let ((hi-lock--inhibit-font-lock-hook t))
+    (font-lock-mode -1))
+  (kill-local-variable 'font-lock-set-defaults)
+  (font-lock-mode 1))
+
 (defvar font-lock-mode-major-mode)
 (defun font-lock-set-defaults ()
   "Set fontification defaults appropriately for this mode.