-;;; easymenu.el --- support the easymenu interface for defining a menu.
+;;; easymenu.el --- support the easymenu interface for defining a menu
-;; Copyright (C) 1994 Free Software Foundation, Inc.
+;; Copyright (C) 1994, 1996, 1998, 1999, 2000, 2002, 2003, 2004,
+;; 2005, 2006 Free Software Foundation, Inc.
;; Keywords: emulations
-;; Author: rms
+;; Author: Richard Stallman <rms@gnu.org>
;; This file is part of GNU Emacs.
;; 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.
+;; along with GNU Emacs; see the file COPYING. If not, write to the
+;; Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
+;; Boston, MA 02110-1301, USA.
-;;; This is compatible with easymenu.el by Per Abrahamsen
-;;; but it is much simpler as it doesn't try to support other Emacs versions.
-;;; The code was mostly derived from lmenu.el.
+;;; Commentary:
+
+;; This is compatible with easymenu.el by Per Abrahamsen
+;; but it is much simpler as it doesn't try to support other Emacs versions.
+;; The code was mostly derived from lmenu.el.
;;; Code:
+(defcustom easy-menu-precalculate-equivalent-keybindings t
+ "Determine when equivalent key bindings are computed for easy-menu menus.
+It can take some time to calculate the equivalent key bindings that are shown
+in a menu. If the variable is on, then this calculation gives a (maybe
+noticeable) delay when a mode is first entered. If the variable is off, then
+this delay will come when a menu is displayed the first time. If you never use
+menus, turn this variable off, otherwise it is probably better to keep it on."
+ :type 'boolean
+ :group 'menu
+ :version "20.3")
+
+(defsubst easy-menu-intern (s)
+ (if (stringp s) (intern s) s))
+
+;;;###autoload
+(put 'easy-menu-define 'lisp-indent-function 'defun)
;;;###autoload
(defmacro easy-menu-define (symbol maps doc menu)
"Define a menu bar submenu in maps MAPS, according to MENU.
-SYMBOL is used as a variable to hold the menu data. It is not evaluated.
-DOC is a doc string for that variable.
+
+If SYMBOL is non-nil, store the menu keymap in the value of SYMBOL,
+and define SYMBOL as a function to pop up the menu, with DOC as its doc string.
+If SYMBOL is nil, just store the menu keymap into MAPS.
The first element of MENU must be a string. It is the menu bar item name.
-The rest of the elements are menu items.
+It may be followed by the following keyword argument pairs
+
+ :filter FUNCTION
+
+FUNCTION is a function with one argument, the rest of menu items.
+It returns the remaining items of the displayed menu.
+
+ :visible INCLUDE
+
+INCLUDE is an expression; this menu is only visible if this
+expression has a non-nil value. `:included' is an alias for `:visible'.
+
+ :active ENABLE
+
+ENABLE is an expression; the menu is enabled for selection
+whenever this expression's value is non-nil.
+
+The rest of the elements in MENU, are menu items.
A menu item is usually a vector of three elements: [NAME CALLBACK ENABLE]
ENABLE is an expression; the item is enabled for selection
whenever this expression's value is non-nil.
-Alternatively, a menu item may have the form:
+Alternatively, a menu item may have the form:
[ NAME CALLBACK [ KEYWORD ARG ] ... ]
-Where KEYWORD is one of the symbol defined below.
+Where KEYWORD is one of the symbols defined below.
:keys KEYS
KEYS is a string; a complex keyboard equivalent to this menu item.
This is normally not needed because keyboard equivalents are usually
computed automatically.
+KEYS is expanded with `substitute-command-keys' before it is used.
+
+ :key-sequence KEYS
+
+KEYS is nil, a string or a vector; nil or a keyboard equivalent to this
+menu item.
+This is a hint that will considerably speed up Emacs' first display of
+a menu. Use `:key-sequence nil' when you know that this menu item has no
+keyboard equivalent.
:active ENABLE
ENABLE is an expression; the item is enabled for selection
whenever this expression's value is non-nil.
- :suffix NAME
+ :visible INCLUDE
+
+INCLUDE is an expression; this item is only visible if this
+expression has a non-nil value. `:included' is an alias for `:visible'.
+
+ :suffix FORM
-NAME is a string; the name of an argument to CALLBACK.
+FORM is an expression that will be dynamically evaluated and whose
+value will be concatenated to the menu entry's NAME.
+
+ :style STYLE
- :style
-
STYLE is a symbol describing the type of menu item. The following are
-defined:
+defined:
-toggle: A checkbox.
- Currently just prepend the name with the string \"Toggle \".
-radio: A radio button.
-nil: An ordinary menu item.
+toggle: A checkbox.
+ Prepend the name with `(*) ' or `( ) ' depending on if selected or not.
+radio: A radio button.
+ Prepend the name with `[X] ' or `[ ] ' depending on if selected or not.
+button: Surround the name with `[' and `]'. Use this for an item in the
+ menu bar itself.
+anything else means an ordinary menu item.
:selected SELECTED
SELECTED is an expression; the checkbox or radio button is selected
whenever this expression's value is non-nil.
-Currently just disable radio buttons, no effect on checkboxes.
+
+ :help HELP
+
+HELP is a string, the help to display for the menu item.
A menu item can be a string. Then that string appears in the menu as
unselectable text. A string consisting solely of hyphens is displayed
as a solid horizontal line.
-A menu item can be a list. It is treated as a submenu.
-The first element should be the submenu name. That's used as the
-menu item in the top-level menu. The cdr of the submenu list
-is a list of menu items, as above."
- (` (progn
- (defvar (, symbol) nil (, doc))
- (easy-menu-do-define (quote (, symbol)) (, maps) (, doc) (, menu)))))
+A menu item can be a list with the same format as MENU. This is a submenu."
+ `(progn
+ ,(if symbol `(defvar ,symbol nil ,doc))
+ (easy-menu-do-define (quote ,symbol) ,maps ,doc ,menu)))
+;;;###autoload
(defun easy-menu-do-define (symbol maps doc menu)
;; We can't do anything that might differ between Emacs dialects in
;; `easy-menu-define' in order to make byte compiled files
;; compatible. Therefore everything interesting is done in this
- ;; function.
- (set symbol (easy-menu-create-keymaps (car menu) (cdr menu)))
- (fset symbol (` (lambda (event) (, doc) (interactive "@e")
- (easy-popup-menu event (, symbol)))))
- (mapcar (function (lambda (map)
- (define-key map (vector 'menu-bar (intern (car menu)))
- (cons (car menu) (symbol-value symbol)))))
- (if (keymapp maps) (list maps) maps)))
-
-(defvar easy-menu-item-count 0)
+ ;; function.
+ (let ((keymap (easy-menu-create-menu (car menu) (cdr menu))))
+ (when symbol
+ (set symbol keymap)
+ (defalias symbol
+ `(lambda (event) ,doc (interactive "@e")
+ ;; FIXME: XEmacs uses popup-menu which calls the binding
+ ;; while x-popup-menu only returns the selection.
+ (x-popup-menu event
+ (or (and (symbolp ,symbol)
+ (funcall
+ (or (plist-get (get ,symbol 'menu-prop)
+ :filter)
+ 'identity)
+ (symbol-function ,symbol)))
+ ,symbol)))))
+ (mapcar (lambda (map)
+ (define-key map (vector 'menu-bar (easy-menu-intern (car menu)))
+ (cons 'menu-item
+ (cons (car menu)
+ (if (not (symbolp keymap))
+ (list keymap)
+ (cons (symbol-function keymap)
+ (get keymap 'menu-prop)))))))
+ (if (keymapp maps) (list maps) maps))))
+
+(defun easy-menu-filter-return (menu &optional name)
+ "Convert MENU to the right thing to return from a menu filter.
+MENU is a menu as computed by `easy-menu-define' or `easy-menu-create-menu' or
+a symbol whose value is such a menu.
+In Emacs a menu filter must return a menu (a keymap), in XEmacs a filter must
+return a menu items list (without menu name and keywords).
+This function returns the right thing in the two cases.
+If NAME is provided, it is used for the keymap."
+ (cond
+ ((and (not (keymapp menu)) (consp menu))
+ ;; If it's a cons but not a keymap, then it can't be right
+ ;; unless it's an XEmacs menu.
+ (setq menu (easy-menu-create-menu (or name "") menu)))
+ ((vectorp menu)
+ ;; It's just a menu entry.
+ (setq menu (cdr (easy-menu-convert-item menu)))))
+ menu)
-;; Return a menu keymap corresponding to a Lucid-style menu list
-;; MENU-ITEMS, and with name MENU-NAME.
;;;###autoload
-(defun easy-menu-create-keymaps (menu-name menu-items)
- (let ((menu (make-sparse-keymap menu-name)))
- ;; Process items in reverse order,
- ;; since the define-key loop reverses them again.
- (setq menu-items (reverse menu-items))
- (while menu-items
- (let* ((item (car menu-items))
- (callback (if (vectorp item) (aref item 1)))
- command enabler name)
- (cond ((stringp item)
- (setq command nil)
- (setq name (if (string-match "^-+$" item) "" item)))
- ((consp item)
- (setq command (easy-menu-create-keymaps (car item) (cdr item)))
- (setq name (car item)))
- ((vectorp item)
- (setq command (make-symbol (format "menu-function-%d"
- easy-menu-item-count)))
- (setq easy-menu-item-count (1+ easy-menu-item-count))
- (setq name (aref item 0))
- (let ((keyword (aref item 2)))
- (if (and (symbolp keyword)
- (= ?: (aref (symbol-name keyword) 0)))
- (let ((count 2)
- style selected active keys
- arg)
- (while (> (length item) count)
- (setq keyword (aref item count))
- (setq arg (aref item (1+ count)))
- (setq count (+ 2 count))
- (cond ((eq keyword ':keys)
- (setq keys arg))
- ((eq keyword ':active)
- (setq active arg))
- ((eq keyword ':suffix)
- (setq name (concat name " " arg)))
- ((eq keyword ':style)
- (setq style arg))
- ((eq keyword ':selected)
- (setq selected arg))))
- (if keys
- (setq name (concat name " (" keys ")")))
- (if (eq style 'toggle)
- ;; Simulate checkboxes.
- (setq name (concat "Toggle " name)))
- (if active
- (put command 'menu-enable active)
- (and (eq style 'radio)
- selected
- ;; Simulate radio buttons with menu-enable.
- (put command 'menu-enable
- (list 'not selected)))))))
- (if (keymapp callback)
- (setq name (concat name " ...")))
- (if (symbolp callback)
- (fset command callback)
- (fset command (list 'lambda () '(interactive) callback)))))
- (if (null command)
- ;; Handle inactive strings specially--allow any number
- ;; of identical ones.
- (setcdr menu (cons (list nil name) (cdr menu)))
- (if name
- (define-key menu (vector (intern name)) (cons name command)))))
- (setq menu-items (cdr menu-items)))
- menu))
-
-(defun easy-menu-change (path name items)
- "Change menu found at PATH as item NAME to contain ITEMS.
-PATH is a list of strings for locating the menu containing NAME in the
-menu bar. ITEMS is a list of menu items, as in `easy-menu-define'.
-These items entirely replace the previous items in that map.
+(defun easy-menu-create-menu (menu-name menu-items)
+ "Create a menu called MENU-NAME with items described in MENU-ITEMS.
+MENU-NAME is a string, the name of the menu. MENU-ITEMS is a list of items
+possibly preceded by keyword pairs as described in `easy-menu-define'."
+ (let ((menu (make-sparse-keymap menu-name))
+ prop keyword arg label enable filter visible help)
+ ;; Look for keywords.
+ (while (and menu-items
+ (cdr menu-items)
+ (keywordp (setq keyword (car menu-items))))
+ (setq arg (cadr menu-items))
+ (setq menu-items (cddr menu-items))
+ (cond
+ ((eq keyword :filter)
+ (setq filter `(lambda (menu)
+ (easy-menu-filter-return (,arg menu) ,menu-name))))
+ ((eq keyword :active) (setq enable (or arg ''nil)))
+ ((eq keyword :label) (setq label arg))
+ ((eq keyword :help) (setq help arg))
+ ((or (eq keyword :included) (eq keyword :visible))
+ (setq visible (or arg ''nil)))))
+ (if (equal visible ''nil)
+ nil ; Invisible menu entry, return nil.
+ (if (and visible (not (easy-menu-always-true-p visible)))
+ (setq prop (cons :visible (cons visible prop))))
+ (if (and enable (not (easy-menu-always-true-p enable)))
+ (setq prop (cons :enable (cons enable prop))))
+ (if filter (setq prop (cons :filter (cons filter prop))))
+ (if help (setq prop (cons :help (cons help prop))))
+ (if label (setq prop (cons nil (cons label prop))))
+ (if filter
+ ;; The filter expects the menu in its XEmacs form and the pre-filter
+ ;; form will only be passed to the filter anyway, so we'd better
+ ;; not convert it at all (it will be converted on the fly by
+ ;; easy-menu-filter-return).
+ (setq menu menu-items)
+ (setq menu (append menu (mapcar 'easy-menu-convert-item menu-items))))
+ (when prop
+ (setq menu (easy-menu-make-symbol menu 'noexp))
+ (put menu 'menu-prop prop))
+ menu)))
+
+
+;; Known button types.
+(defvar easy-menu-button-prefix
+ '((radio . :radio) (toggle . :toggle)))
+
+(defun easy-menu-do-add-item (menu item &optional before)
+ (setq item (easy-menu-convert-item item))
+ (easy-menu-define-key menu (easy-menu-intern (car item)) (cdr item) before))
+
+(defvar easy-menu-converted-items-table (make-hash-table :test 'equal))
+
+(defun easy-menu-convert-item (item)
+ "Memoize the value returned by `easy-menu-convert-item-1' called on ITEM.
+This makes key-shortcut-caching work a *lot* better when this
+conversion is done from within a filter.
+This also helps when the NAME of the entry is recreated each time:
+since the menu is built and traversed separately, the lookup
+would always fail because the key is `equal' but not `eq'."
+ (or (gethash item easy-menu-converted-items-table)
+ (puthash item (easy-menu-convert-item-1 item)
+ easy-menu-converted-items-table)))
+
+(defun easy-menu-convert-item-1 (item)
+ "Parse an item description and convert it to a menu keymap element.
+ITEM defines an item as in `easy-menu-define'."
+ (let (name command label prop remove help)
+ (cond
+ ((stringp item) ; An item or separator.
+ (setq label item))
+ ((consp item) ; A sub-menu
+ (setq label (setq name (car item)))
+ (setq command (cdr item))
+ (if (not (keymapp command))
+ (setq command (easy-menu-create-menu name command)))
+ (if (null command)
+ ;; Invisible menu item. Don't insert into keymap.
+ (setq remove t)
+ (when (and (symbolp command) (setq prop (get command 'menu-prop)))
+ (when (null (car prop))
+ (setq label (cadr prop))
+ (setq prop (cddr prop)))
+ (setq command (symbol-function command)))))
+ ((vectorp item) ; An item.
+ (let* ((ilen (length item))
+ (active (if (> ilen 2) (or (aref item 2) ''nil) t))
+ (no-name (not (symbolp (setq command (aref item 1)))))
+ cache cache-specified)
+ (setq label (setq name (aref item 0)))
+ (if no-name (setq command (easy-menu-make-symbol command)))
+ (if (keywordp active)
+ (let ((count 2)
+ keyword arg suffix visible style selected keys)
+ (setq active nil)
+ (while (> ilen count)
+ (setq keyword (aref item count))
+ (setq arg (aref item (1+ count)))
+ (setq count (+ 2 count))
+ (cond
+ ((or (eq keyword :included) (eq keyword :visible))
+ (setq visible (or arg ''nil)))
+ ((eq keyword :key-sequence)
+ (setq cache arg cache-specified t))
+ ((eq keyword :keys) (setq keys arg no-name nil))
+ ((eq keyword :label) (setq label arg))
+ ((eq keyword :active) (setq active (or arg ''nil)))
+ ((eq keyword :help) (setq prop (cons :help (cons arg prop))))
+ ((eq keyword :suffix) (setq suffix arg))
+ ((eq keyword :style) (setq style arg))
+ ((eq keyword :selected) (setq selected (or arg ''nil)))))
+ (if suffix
+ (setq label
+ (if (stringp suffix)
+ (if (stringp label) (concat label " " suffix)
+ (list 'concat label (concat " " suffix)))
+ (if (stringp label)
+ (list 'concat (concat label " ") suffix)
+ (list 'concat label " " suffix)))))
+ (cond
+ ((eq style 'button)
+ (setq label (if (stringp label) (concat "[" label "]")
+ (list 'concat "[" label "]"))))
+ ((and selected
+ (setq style (assq style easy-menu-button-prefix)))
+ (setq prop (cons :button
+ (cons (cons (cdr style) selected) prop)))))
+ (when (stringp keys)
+ (if (string-match "^[^\\]*\\(\\\\\\[\\([^]]+\\)]\\)[^\\]*$"
+ keys)
+ (let ((prefix
+ (if (< (match-beginning 0) (match-beginning 1))
+ (substring keys 0 (match-beginning 1))))
+ (postfix
+ (if (< (match-end 1) (match-end 0))
+ (substring keys (match-end 1))))
+ (cmd (intern (match-string 2 keys))))
+ (setq keys (and (or prefix postfix)
+ (cons prefix postfix)))
+ (setq keys
+ (and (or keys (not (eq command cmd)))
+ (cons cmd keys))))
+ (setq cache-specified nil))
+ (if keys (setq prop (cons :keys (cons keys prop)))))
+ (if (and visible (not (easy-menu-always-true-p visible)))
+ (if (equal visible ''nil)
+ ;; Invisible menu item. Don't insert into keymap.
+ (setq remove t)
+ (setq prop (cons :visible (cons visible prop)))))))
+ (if (and active (not (easy-menu-always-true-p active)))
+ (setq prop (cons :enable (cons active prop))))
+ (if (and (or no-name cache-specified)
+ (or (null cache) (stringp cache) (vectorp cache)))
+ (setq prop (cons :key-sequence (cons cache prop))))))
+ (t (error "Invalid menu item in easymenu")))
+ ;; `intern' the name so as to merge multiple entries with the same name.
+ ;; It also makes it easier/possible to lookup/change menu bindings
+ ;; via keymap functions.
+ (cons (easy-menu-intern name)
+ (and (not remove)
+ (cons 'menu-item
+ (cons label
+ (and name
+ (cons command prop))))))))
+
+(defun easy-menu-define-key (menu key item &optional before)
+ "Add binding in MENU for KEY => ITEM. Similar to `define-key-after'.
+If KEY is not nil then delete any duplications.
+If ITEM is nil, then delete the definition of KEY.
+
+Optional argument BEFORE is nil or a key in MENU. If BEFORE is not nil,
+put binding before the item in MENU named BEFORE; otherwise,
+if a binding for KEY is already present in MENU, just change it;
+otherwise put the new binding last in MENU.
+BEFORE can be either a string (menu item name) or a symbol
+\(the fake function key for the menu item).
+KEY does not have to be a symbol, and comparison is done with equal."
+ (if (symbolp menu) (setq menu (indirect-function menu)))
+ (let ((inserted (null item)) ; Fake already inserted.
+ tail done)
+ (while (not done)
+ (cond
+ ((or (setq done (or (null (cdr menu)) (keymapp (cdr menu))))
+ (and before (easy-menu-name-match before (cadr menu))))
+ ;; If key is nil, stop here, otherwise keep going past the
+ ;; inserted element so we can delete any duplications that come
+ ;; later.
+ (if (null key) (setq done t))
+ (unless inserted ; Don't insert more than once.
+ (setcdr menu (cons (cons key item) (cdr menu)))
+ (setq inserted t)
+ (setq menu (cdr menu)))
+ (setq menu (cdr menu)))
+ ((and key (equal (car-safe (cadr menu)) key))
+ (if (or inserted ; Already inserted or
+ (and before ; wanted elsewhere and
+ (setq tail (cddr menu)) ; not last item and not
+ (not (keymapp tail))
+ (not (easy-menu-name-match
+ before (car tail))))) ; in position
+ (setcdr menu (cddr menu)) ; Remove item.
+ (setcdr (cadr menu) item) ; Change item.
+ (setq inserted t)
+ (setq menu (cdr menu))))
+ (t (setq menu (cdr menu)))))))
+
+(defun easy-menu-name-match (name item)
+ "Return t if NAME is the name of menu item ITEM.
+NAME can be either a string, or a symbol.
+ITEM should be a keymap binding of the form (KEY . MENU-ITEM)."
+ (if (consp item)
+ (if (symbolp name)
+ (eq (car-safe item) name)
+ (if (stringp name)
+ ;; Match against the text that is displayed to the user.
+ (or (condition-case nil (member-ignore-case name item)
+ (error nil)) ;`item' might not be a proper list.
+ ;; Also check the string version of the symbol name,
+ ;; for backwards compatibility.
+ (eq (car-safe item) (intern name)))))))
+
+(defun easy-menu-always-true-p (x)
+ "Return true if form X never evaluates to nil."
+ (if (consp x) (and (eq (car x) 'quote) (cadr x))
+ (or (eq x t) (not (symbolp x)))))
-Call this from `activate-menubar-hook' to implement dynamic menus."
- (let ((map (key-binding (apply 'vector
- 'menu-bar
- (mapcar 'intern (append path (list name)))))))
- (if (keymapp map)
- (setcdr map (cdr (easy-menu-create-keymaps name items)))
- (error "Malformed menu in `easy-menu-change'"))))
+(defvar easy-menu-item-count 0)
-(defun easy-menu-remove (menu))
+(defun easy-menu-make-symbol (callback &optional noexp)
+ "Return a unique symbol with CALLBACK as function value.
+When non-nil, NOEXP indicates that CALLBACK cannot be an expression
+\(i.e. does not need to be turned into a function)."
+ (let ((command
+ (make-symbol (format "menu-function-%d" easy-menu-item-count))))
+ (setq easy-menu-item-count (1+ easy-menu-item-count))
+ (fset command
+ (if (or (keymapp callback) (functionp callback) noexp) callback
+ `(lambda () (interactive) ,callback)))
+ command))
-(defun easy-menu-add (menu &optional map))
+;;;###autoload
+(defun easy-menu-change (path name items &optional before)
+ "Change menu found at PATH as item NAME to contain ITEMS.
+PATH is a list of strings for locating the menu that
+should contain a submenu named NAME.
+ITEMS is a list of menu items, as in `easy-menu-define'.
+These items entirely replace the previous items in that submenu.
+
+If the menu located by PATH has no submenu named NAME, add one.
+If the optional argument BEFORE is present, add it just before
+the submenu named BEFORE, otherwise add it at the end of the menu.
+
+To implement dynamic menus, either call this from
+`menu-bar-update-hook' or use a menu filter."
+ (easy-menu-add-item nil path (easy-menu-create-menu name items) before))
+
+;; XEmacs needs the following two functions to add and remove menus.
+;; In Emacs this is done automatically when switching keymaps, so
+;; here easy-menu-remove is a noop and easy-menu-add only precalculates
+;; equivalent keybindings (if easy-menu-precalculate-equivalent-keybindings
+;; is on).
+(defalias 'easy-menu-remove 'ignore
+ "Remove MENU from the current menu bar.
+Contrary to XEmacs, this is a nop on Emacs since menus are automatically
+\(de)activated when the corresponding keymap is (de)activated.
+
+\(fn MENU)")
+
+(defun easy-menu-add (menu &optional map)
+ "Add the menu to the menubar.
+On Emacs, menus are already automatically activated when the
+corresponding keymap is activated. On XEmacs this is needed to
+actually add the menu to the current menubar.
+
+This also precalculates equivalent key bindings when
+`easy-menu-precalculate-equivalent-keybindings' is on.
+
+You should call this once the menu and keybindings are set up
+completely and menu filter functions can be expected to work."
+ (when easy-menu-precalculate-equivalent-keybindings
+ (if (and (symbolp menu) (not (keymapp menu)) (boundp menu))
+ (setq menu (symbol-value menu)))
+ (and (keymapp menu) (fboundp 'x-popup-menu)
+ (x-popup-menu nil menu))
+ ))
+
+(defun add-submenu (menu-path submenu &optional before in-menu)
+ "Add submenu SUBMENU in the menu at MENU-PATH.
+If BEFORE is non-nil, add before the item named BEFORE.
+If IN-MENU is non-nil, follow MENU-PATH in IN-MENU.
+This is a compatibility function; use `easy-menu-add-item'."
+ (easy-menu-add-item (or in-menu (current-global-map))
+ (cons "menu-bar" menu-path)
+ submenu before))
+
+(defun easy-menu-add-item (map path item &optional before)
+ "To the submenu of MAP with path PATH, add ITEM.
+
+If an item with the same name is already present in this submenu,
+then ITEM replaces it. Otherwise, ITEM is added to this submenu.
+In the latter case, ITEM is normally added at the end of the submenu.
+However, if BEFORE is a string and there is an item in the submenu
+with that name, then ITEM is added before that item.
+
+MAP should normally be a keymap; nil stands for the local menu-bar keymap.
+It can also be a symbol, which has earlier been used as the first
+argument in a call to `easy-menu-define', or the value of such a symbol.
+
+PATH is a list of strings for locating the submenu where ITEM is to be
+added. If PATH is nil, MAP itself is used. Otherwise, the first
+element should be the name of a submenu directly under MAP. This
+submenu is then traversed recursively with the remaining elements of PATH.
+
+ITEM is either defined as in `easy-menu-define' or a non-nil value returned
+by `easy-menu-item-present-p' or `easy-menu-remove-item' or a menu defined
+earlier by `easy-menu-define' or `easy-menu-create-menu'."
+ (setq map (easy-menu-get-map map path
+ (and (null map) (null path)
+ (stringp (car-safe item))
+ (car item))))
+ (if (and (consp item) (consp (cdr item)) (eq (cadr item) 'menu-item))
+ ;; This is a value returned by `easy-menu-item-present-p' or
+ ;; `easy-menu-remove-item'.
+ (easy-menu-define-key map (easy-menu-intern (car item))
+ (cdr item) before)
+ (if (or (keymapp item)
+ (and (symbolp item) (keymapp (symbol-value item))
+ (setq item (symbol-value item))))
+ ;; Item is a keymap, find the prompt string and use as item name.
+ (setq item (cons (keymap-prompt item) item)))
+ (easy-menu-do-add-item map item before)))
+
+(defun easy-menu-item-present-p (map path name)
+ "In submenu of MAP with path PATH, return non-nil iff item NAME is present.
+MAP and PATH are defined as in `easy-menu-add-item'.
+NAME should be a string, the name of the element to be looked for."
+ (easy-menu-return-item (easy-menu-get-map map path) name))
+
+(defun easy-menu-remove-item (map path name)
+ "From submenu of MAP with path PATH remove item NAME.
+MAP and PATH are defined as in `easy-menu-add-item'.
+NAME should be a string, the name of the element to be removed."
+ (setq map (easy-menu-get-map map path))
+ (let ((ret (easy-menu-return-item map name)))
+ (if ret (easy-menu-define-key map (easy-menu-intern name) nil))
+ ret))
+
+(defun easy-menu-return-item (menu name)
+ "In menu MENU try to look for menu item with name NAME.
+If a menu item is found, return (NAME . item), otherwise return nil.
+If item is an old format item, a new format item is returned."
+ ;; The call to `lookup-key' also calls the C function `get_keyelt' which
+ ;; looks inside a menu-item to only return the actual command. This is
+ ;; not what we want here. We should either add an arg to lookup-key to be
+ ;; able to turn off this "feature", or else we could use map-keymap here.
+ ;; In the mean time, I just use `assq' which is an OK approximation since
+ ;; menus are rarely built from vectors or char-tables.
+ (let ((item (or (cdr (assq name menu))
+ (lookup-key menu (vector (easy-menu-intern name)))))
+ ret enable cache label)
+ (cond
+ ((stringp (car-safe item))
+ ;; This is the old menu format. Convert it to new format.
+ (setq label (car item))
+ (when (stringp (car (setq item (cdr item)))) ; Got help string
+ (setq ret (list :help (car item)))
+ (setq item (cdr item)))
+ (when (and (consp item) (consp (car item))
+ (or (null (caar item)) (numberp (caar item))))
+ (setq cache (car item)) ; Got cache
+ (setq item (cdr item)))
+ (and (symbolp item) (setq enable (get item 'menu-enable)) ; Got enable
+ (setq ret (cons :enable (cons enable ret))))
+ (if cache (setq ret (cons cache ret)))
+ (cons name (cons 'menu-enable (cons label (cons item ret)))))
+ (item ; (or (symbolp item) (keymapp item) (eq (car-safe item) 'menu-item))
+ (cons name item)) ; Keymap or new menu format
+ )))
+
+(defun easy-menu-lookup-name (map name)
+ "Lookup menu item NAME in keymap MAP.
+Like `lookup-key' except that NAME is not an array but just a single key
+and that NAME can be a string representing the menu item's name."
+ (or (lookup-key map (vector (easy-menu-intern name)))
+ (when (stringp name)
+ ;; `lookup-key' failed and we have a menu item name: look at the
+ ;; actual menu entries's names.
+ (catch 'found
+ (map-keymap (lambda (key item)
+ (if (condition-case nil (member name item)
+ (error nil))
+ ;; Found it!! Look for it again with
+ ;; `lookup-key' so as to handle inheritance and
+ ;; to extract the actual command/keymap bound to
+ ;; `name' from the item (via get_keyelt).
+ (throw 'found (lookup-key map (vector key)))))
+ map)))))
+
+(defun easy-menu-get-map (map path &optional to-modify)
+ "Return a sparse keymap in which to add or remove an item.
+MAP and PATH are as defined in `easy-menu-add-item'.
+
+TO-MODIFY, if non-nil, is the name of the item the caller
+wants to modify in the map that we return.
+In some cases we use that to select between the local and global maps."
+ (setq map
+ (catch 'found
+ (if (and map (symbolp map) (not (keymapp map)))
+ (setq map (symbol-value map)))
+ (let ((maps (if map (list map) (current-active-maps))))
+ ;; Look for PATH in each map.
+ (unless map (push 'menu-bar path))
+ (dolist (name path)
+ (setq maps
+ (delq nil (mapcar (lambda (map)
+ (setq map (easy-menu-lookup-name
+ map name))
+ (and (keymapp map) map))
+ maps))))
+
+ ;; Prefer a map that already contains the to-be-modified entry.
+ (when to-modify
+ (dolist (map maps)
+ (when (easy-menu-lookup-name map to-modify)
+ (throw 'found map))))
+ ;; Use the first valid map.
+ (when maps (throw 'found (car maps)))
+
+ ;; Otherwise, make one up.
+ ;; Hardcoding current-local-map is lame, but it's difficult
+ ;; to know what the caller intended for us to do ;-(
+ (let* ((name (if path (format "%s" (car (reverse path)))))
+ (newmap (make-sparse-keymap name)))
+ (define-key (or map (current-local-map))
+ (apply 'vector (mapcar 'easy-menu-intern path))
+ (if name (cons name newmap) newmap))
+ newmap))))
+ (or (keymapp map) (error "Malformed menu in easy-menu: (%s)" map))
+ map)
(provide 'easymenu)
+;; arch-tag: 2a04020d-90d2-476d-a7c6-71e072007a4a
;;; easymenu.el ends here