(menu-bar-update-buffers): Reuse the entry for

list-buffers rather than making a new one each time.

diff --git a/lisp/menu-bar.el b/lisp/menu-bar.el
index 1bb226f7a8c7da5e862759ab941ff3a506bcd9f2..693cba220fd457a34400684afa676a860d155eb5 100644 (file)
--- a/lisp/menu-bar.el
+++ b/lisp/menu-bar.el
@@ -429,6 +429,8 @@ A large number or nil slows down menu responsiveness.")
           file))
        (car elt)))
 
+(defvar menu-bar-buffers-menu-list-buffers-entry nil)
+
 (defun menu-bar-update-buffers ()
   ;; If user discards the Buffers item, play along.
   (and (lookup-key (current-global-map) [menu-bar buffer])
@@ -486,6 +488,25 @@ A large number or nil slows down menu responsiveness.")
                                (setq maxlen (length (car (car alist))))))
                         (setq tail (cdr tail)))
                       (setq alist (nreverse alist))
+                      ;; Make the menu item for list-buffers
+                      ;; or reuse the one we already have.
+                      ;; The advantage in reusing one
+                      ;; is that it already has the keyboard equivalent
+                      ;; cached, so we save the time to look that up again.
+                      (or menu-bar-buffers-menu-list-buffers-entry
+                          (setq menu-bar-buffers-menu-list-buffers-entry
+                                (cons
+                                 'list-buffers
+                                 (cons
+                                  ""
+                                  'list-buffers))))
+                      ;; Update the item string for menu's new width.
+                      (setcar (cdr menu-bar-buffers-menu-list-buffers-entry)
+                              (concat (make-string (max (- (/ maxlen 2) 8) 0)
+                                                   ?\ )
+                                      "List All Buffers"))
+                      ;; Now make the actual list of items,
+                      ;; ending with the list-buffers item.
                       (nconc (mapcar '(lambda (pair)
                                         ;; This is somewhat risque, to use
                                         ;; the buffer name itself as the event
@@ -498,14 +519,7 @@ A large number or nil slows down menu responsiveness.")
                                                      (cons nil nil))
                                                'menu-bar-select-buffer))
                                      alist)
-                             (list
-                              (cons
-                               'list-buffers
-                               (cons
-                                (concat (make-string (max (- (/ maxlen 2) 8) 0)
-                                                     ?\ )
-                                        "List All Buffers")
-                                'list-buffers)))))))
+                             (list menu-bar-buffers-menu-list-buffers-entry)))))
 
 
         ;; Make a Frames menu if we have more than one frame.