(picture-replace-match): New function.

diff --git a/lisp/textmodes/picture.el b/lisp/textmodes/picture.el
index b8a1ec0c5c2438d7f73ae50f9509014b690b5e92..3b6a5fe232cfb15390fafbac9a96d07e6f7d0261 100644 (file)
--- a/lisp/textmodes/picture.el
+++ b/lisp/textmodes/picture.el
@@ -263,6 +263,28 @@ With positive argument insert that many lines."
      (forward-line -1)
      (insert contents))))
 
+;; Like replace-match, but overwrites.
+(defun picture-replace-match (newtext fixedcase literal)
+  (let (ocolumn change pos)
+    (goto-char (setq pos (match-end 0)))
+    (setq ocolumn (current-column))
+    ;; Make the replacement and undo it, to see how it changes the length.
+    (let ((buffer-undo-list nil)
+         list1)
+      (replace-match newtext fixedcase literal)
+      (setq change (- (current-column) ocolumn))
+      (setq list1 buffer-undo-list)
+      (while list1
+       (setq list1 (primitive-undo 1 list1))))
+    (goto-char pos)
+    (if (> change 0)
+       (delete-region (point)
+                      (progn
+                        (move-to-column-force (+ change (current-column)))
+                        (point))))
+    (replace-match newtext fixedcase literal)
+    (if (< change 0)
+       (insert-char ?\ (- change)))))
 \f
 ;; Picture Tabs