(popup-menu): Redefine as macro.

(popup-menu-popup, popup-menu-internal): New function.

1 files changed, 37 insertions, 8 deletions

diff --git a/lisp/emacs-lisp/lmenu.el b/lisp/emacs-lisp/lmenu.el
index a878f6ca206..dcd95a54006 100644
--- a/lisp/emacs-lisp/lmenu.el
+++ b/lisp/emacs-lisp/lmenu.el
@@ -1,6 +1,6 @@
 ;;; lmenu.el --- emulate Lucid's menubar support
 
-;; Copyright (C) 1992, 1993, 1994 Free Software Foundation, Inc.
+;; Copyright (C) 1992, 1993, 1994, 1997 Free Software Foundation, Inc.
 
 ;; Keywords: emulations
 
@@ -124,7 +124,14 @@
       (setq menu-items (cdr menu-items)))
     menu))
 
-(defun popup-menu (menu-desc)
+;; The value of the cache-symbol for a menu
+;; is
+;;   unbound  --  nothing computed
+;;   (ORIG . TRANSL)
+;;                ORIG is the original menu spec list
+;;                and TRANSL is its translation.
+
+(defmacro popup-menu (arg)
   "Pop up the given menu.
 A menu is a list of menu items, strings, and submenus.
 
@@ -189,19 +196,41 @@ The syntax, more precisely:
    menu-item    :=  '['  name callback active-p [ suffix ]  ']'
                  |  '['  name callback [ keyword ]+  ']'
    menu         :=  '(' name [ menu-item | menu | text ]+ ')'"
-  (let ((menu (make-lucid-menu-keymap (car menu-desc) (cdr menu-desc)))
-        (pos (mouse-pixel-position))
+  (if (not (symbolp arg))
+      `(popup-menu-internal ,arg nil)
+    `(popup-menu-internal ,arg
+                          ',(intern (concat "popup-menu-" (symbol-name arg))))))
+
+(defun popup-menu-internal (menu cache-symbol)
+  (if (null cache-symbol)
+      ;; If no cache symbol, translate the menu afresh each time.
+      (popup-menu-popup (make-lucid-menu-keymap (car menu) (cdr menu)))
+    ;; We have a cache symbol.  See if the cache is valid
+    ;; for the same menu we have now.
+    (or (and (boundp cache-symbol)
+             (consp (symbol-value cache-symbol))
+             (equal (car (symbol-value cache-symbol))
+                    menu))
+        ;; If not, update it.
+        (set cache-symbol
+             (cons menu (make-lucid-menu-keymap (car menu) (cdr menu)))))
+    ;; Use the menu in the cache.
+    (popup-menu-popup (cdr (symbol-value cache-symbol)))))
+
+;; Pop up MENU-KEYMAP which was made by make-lucid-menu-keymap.
+(defun popup-menu-popup (menu-keymap)
+  (let ((pos (mouse-pixel-position))
         answer cmd)
-    (while (and menu
+    (while (and menu-keymap
                 (setq answer (x-popup-menu (list (list (nth 1 pos)
                                                        (nthcdr 2 pos))
                                                  (car pos))
-                                           menu)))
-      (setq cmd (lookup-key menu (apply 'vector answer)))
+                                           menu-keymap)))
+      (setq cmd (lookup-key menu-keymap (apply 'vector answer)))
       (setq menu nil)
       (and cmd
            (if (keymapp cmd)
-               (setq menu cmd)
+               (setq menu-keymap cmd)
              (call-interactively cmd))))))
 
 (defun popup-dialog-box (data)