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diff --git a/lisp/paren.el b/lisp/paren.el
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+;;; paren.el --- highlight matching paren.
+;; Copyright (C) 1993 Software Foundation, Inc.
+
+;; This file is part of GNU Emacs.
+
+;; GNU Emacs is free software; you can redistribute it and/or modify
+;; it under the terms of the GNU General Public License as published by
+;; the Free Software Foundation; either version 2, or (at your option)
+;; any later version.
+
+;; GNU Emacs is distributed in the hope that it will be useful,
+;; but WITHOUT ANY WARRANTY; without even the implied warranty of
+;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+;; GNU General Public License for more details.
+
+;; 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, 675 Mass Ave, Cambridge, MA 02139, USA.
+
+;;; Commentary:
+
+;; Load this and it will display highlighting on whatever
+;; paren matches the one before or after point.
+
+;;; Code:
+
+(defvar blink-paren-overlay nil)
+
+;; Find the place to blink, if there is one,
+;; and blink it until input arrives.
+(defun blink-paren-command-hook ()
+  (let (pos dir mismatch (oldpos (point))
+            (face (if (face-equal 'highlight 'region)
+                      'underline 'highlight)))
+    (cond ((eq (char-syntax (following-char)) ?\()
+           (setq dir 1))
+          ((eq (char-syntax (preceding-char)) ?\))
+           (setq dir -1)))
+    (save-excursion
+      (save-restriction
+        ;; Determine the range within which to look for a match.
+        (if blink-matching-paren-distance
+            (narrow-to-region (max (point-min)
+                                   (- (point) blink-matching-paren-distance))
+                              (min (point-max)
+                                   (+ (point) blink-matching-paren-distance))))
+        ;; Scan across one sexp within that range.
+        (condition-case ()
+            (setq pos (scan-sexps (point) dir))
+          (error nil))
+        ;; See if the "matching" paren is the right kind of paren
+        ;; to match the one we started at.
+        (if pos
+            (let ((beg (min pos oldpos)) (end (max pos oldpos)))
+              (and (/= (char-syntax (char-after beg)) ?\$)
+                   (setq mismatch
+                         (/= (char-after (1- end))
+                             (logand (lsh (aref (syntax-table)
+                                                (char-after beg))
+                                          -8)
+                                     255))))))
+        ;; If they don't properly match, don't blink.
+        (if mismatch
+            (setq pos nil))))
+    (cond (pos
+           (if blink-paren-overlay
+               (move-overlay blink-paren-overlay (- pos dir) pos)
+             (setq blink-paren-overlay
+                   (make-overlay (- pos dir) pos)))
+           (overlay-put blink-paren-overlay 'face face)
+;;; This is code to blink the highlighting.
+;;; It is desirable to avoid this because
+;;; it would interfere with auto-save and gc when idle.
+;;;        (while (sit-for 1)
+;;;          (overlay-put blink-paren-overlay
+;;;                       'face
+;;;                       (if (overlay-get blink-paren-overlay
+;;;                                        'face)
+;;;                           nil face)))
+           )
+          (t
+           (delete-overlay blink-paren-overlay)))))
+
+(add-hook 'post-command-hook 'blink-paren-command-hook)
+