1 files changed, 91 insertions, 73 deletions

diff --git a/lisp/composite.el b/lisp/composite.el
index e73d9ef1ef8..2e6e534172c 100644
--- a/lisp/composite.el
+++ b/lisp/composite.el
@@ -394,15 +394,26 @@ For each character that has to be composed automatically with
 preceding and/or following characters, this char table contains
 a function to call to compose that character.
 
-Each function is called with two arguments, POS and STRING.
+An element, if non-nil, is FUNC or an alist of PATTERNs vs FUNCs,
+where PATTERNs are regular expressions and FUNCs are functions.
+If the element is FUNC, FUNC itself determines the region to
+compose.
 
-If STRING is nil, POS is a position in the current buffer, and the
-function has to compose a character at POS with surrounding characters
-in the current buffer.
+Each function is called with 5 arguments, FROM, TO, FONT-OBJECT,
+and STRING.
 
-Otherwise, STRING is a string, and POS is an index into the string.  In
-this case, the function has to compose a character at POS with
-surrounding characters in the string.
+If STRING is nil, FROM and TO are positions specifying the region
+maching with PATTERN in the current buffer, and the function has
+to compose character in that region (possibly with characters
+preceding FROM).  The return value of the function is the end
+position where characters are composed.
+
+Otherwise, STRING is a string, and FROM and TO are indices into
+the string.  In this case, the function has to compose a
+character in the string.
+
+FONT-OBJECT may be nil if not available (e.g. for the case of
+terminal).
 
 See also the command `toggle-auto-composition'.")
 
@@ -432,28 +443,29 @@ See also the command `toggle-auto-composition'.")
 (defun terminal-composition-modification (from to)
   (terminal-composition-function from))
 
-(defun terminal-composition-function (pos &optional string)
+(defun terminal-composition-function (from to pattern font-object string)
   "General composition function used on terminal.
 Non-spacing characters are composed with the preceding spacing
 character.  All non-spacing characters has this function in
 `terminal-composition-function-table'."
-  (let ((from (1- pos))
-        ch)
+  (let ((pos (1+ from)))
     (if string
-        (length string)
-      (setq pos (1+ pos))
-      (while (and (< pos (point-max))
+        (progn
+          (while (and (< pos to)
+                      (= (aref char-width-table (aref string pos)) 0))
+            (setq pos (1+ pos)))
+          (if (> from 0)
+              (compose-string string (1- from) pos)
+            (compose-string string from pos
+                            (concat " " (buffer-substring from pos)))))
+      (while (and (< pos to)
                   (= (aref char-width-table (char-after pos)) 0))
         (setq pos (1+ pos)))
-      (if (and (>= from (point-min))
-               (= (aref (symbol-name (get-char-code-property
-                                      (char-after from)
-                                      'general-category)) 0) ?L))
-          (compose-region from pos (buffer-substring from pos))
-        (compose-region (1+ from) pos
-                        (concat " " (buffer-substring (1+ from) pos))
-                        'terminal-composition-modification))
-      pos)))
+      (if (> from (point-min))
+          (compose-region (1- from) pos (buffer-substring from pos))
+        (compose-region from pos
+                        (concat " " (buffer-substring from pos)))))
+    pos))
 
 (defvar terminal-composition-function-table
   (let ((table (make-char-table nil)))
@@ -467,62 +479,68 @@ character.  All non-spacing characters has this function in
 This is like `composition-function-table' but used when Emacs is running
 on a terminal.")
 
-(defvar auto-compose-current-font nil
-  "The current font-object used for characters being composed automatically.")
-
-(defun auto-compose-chars (pos string window)
-  "Compose characters after the buffer position POS.
-If STRING is non-nil, it is a string, and POS is an index into the string.
-In that case, compose characters in the string.
+(defun auto-compose-chars (from to window string)
+  "Compose characters in the region between FROM and TO.
 WINDOW is a window displaying the current buffer.
+If STRING is non-nil, it is a string, and FROM and TO are indices
+into the string.  In that case, compose characters in the string.
 
 This function is the default value of `auto-composition-function' (which see)."
   (save-buffer-state nil
     (save-excursion
-      (save-match-data
-        (condition-case nil
-            (let ((start pos)
-                  (limit (if string (length string) (point-max)))
-                  (table (if (display-graphic-p)
-                             composition-function-table
-                           terminal-composition-function-table))
-                  auto-compose-current-font
-                  ch func newpos)
-              (setq limit
-                    (or (text-property-any (1+ pos) limit 'auto-composed t
-                                           string)
-                        limit)
-                    pos 
-                    (catch 'tag
-                      (if string
-                          (while (< pos limit)
-                            (setq ch (aref string pos))
-                            (if (= ch ?\n)
-                                (throw 'tag (1+ pos)))
-                            (setq func (aref table ch))
-                            (if (and (functionp func)
-                                     (setq auto-compose-current-font
-                                           (and window
-                                                (font-at pos window string)))
-                                     (setq newpos (funcall func pos string))
-                                     (> newpos pos))
-                                (setq pos newpos)
-                              (setq pos (1+ pos))))
-                        (while (< pos limit)
-                          (setq ch (char-after pos))
-                          (if (= ch ?\n)
-                              (throw 'tag (1+ pos)))
-                          (setq func (aref table ch))
-                          (if (and (functionp func)
-                                   (setq auto-compose-current-font
-                                         (and window (font-at pos window)))
-                                   (setq newpos (funcall func pos string))
-                                   (> newpos pos))
-                              (setq pos newpos)
-                            (setq pos (1+ pos)))))
-                      limit))
-              (put-text-property start pos 'auto-composed t string))
-          (error nil))))))
+      (save-restriction
+        (save-match-data
+          (let ((table (if (display-graphic-p)
+                           composition-function-table
+                         terminal-composition-function-table))
+                (start from))
+            (setq to (or (text-property-any (1+ from) to 'auto-composed t
+                                            string)
+                         to))
+            (if string
+                (while (< from to)
+                  (let* ((ch (aref string from))
+                         (elt (aref table ch))
+                         font-obj newpos)
+                    (when elt
+                      (if window
+                          (setq font-obj (font-at from window string)))
+                      (if (functionp elt)
+                          (setq newpos (funcall elt from to font-obj string))
+                        (while (and elt
+                                    (or (not (eq (string-match (caar elt) string
+                                                               from)
+                                                 from))
+                                        (not (setq newpos
+                                                   (funcall (cdar elt) from
+                                                            (match-end 0)
+                                                            font-obj string)))))
+                          (setq elt (cdr elt)))))
+                    (if (and newpos (> newpos from))
+                        (setq from newpos)
+                      (setq from (1+ from)))))
+              (narrow-to-region from to)
+              (while (< from to)
+                  (let* ((ch (char-after from))
+                         (elt (aref table ch))
+                         func pattern font-obj newpos)
+                    (when elt
+                      (if window
+                          (setq font-obj (font-at from window)))
+                      (if (functionp elt)
+                          (setq newpos (funcall elt from to font-obj nil))
+                        (goto-char from)
+                        (while (and elt
+                                    (or (not (looking-at (caar elt)))
+                                        (not (setq newpos
+                                                   (funcall (cdar elt) from
+                                                            (match-end 0)
+                                                            font-obj nil)))))
+                          (setq elt (cdr elt)))))
+                    (if (and newpos (> newpos from))
+                        (setq from newpos)
+                      (setq from (1+ from))))))
+            (put-text-property start to 'auto-composed t string)))))))
 
 (make-variable-buffer-local 'auto-composition-function)