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1 ;;; easymenu.el --- support the easymenu interface for defining a menu -*- lexical-binding:t -*-
3 ;; Copyright (C) 1994, 1996, 1998-2017 Free Software Foundation, Inc.
5 ;; Keywords: emulations
6 ;; Author: Richard Stallman <rms@gnu.org>
7 ;; Package: emacs
9 ;; This file is part of GNU Emacs.
11 ;; GNU Emacs is free software: you can redistribute it and/or modify
12 ;; it under the terms of the GNU General Public License as published by
13 ;; the Free Software Foundation, either version 3 of the License, or
14 ;; (at your option) any later version.
16 ;; GNU Emacs is distributed in the hope that it will be useful,
17 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
18 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
19 ;; GNU General Public License for more details.
21 ;; You should have received a copy of the GNU General Public License
22 ;; along with GNU Emacs. If not, see <http://www.gnu.org/licenses/>.
24 ;;; Commentary:
26 ;; This is compatible with easymenu.el by Per Abrahamsen
27 ;; but it is much simpler as it doesn't try to support other Emacs versions.
28 ;; The code was mostly derived from lmenu.el.
30 ;;; Code:
33 "Determine when equivalent key bindings are computed for easy-menu menus.
34 It can take some time to calculate the equivalent key bindings that are shown
35 in a menu. If the variable is on, then this calculation gives a (maybe
36 noticeable) delay when a mode is first entered. If the variable is off, then
37 this delay will come when a menu is displayed the first time. If you never use
45 ;;;###autoload
47 "Define a pop-up menu and/or menu bar menu specified by MENU.
48 If SYMBOL is non-nil, define SYMBOL as a function to pop up the
49 submenu defined by MENU, with DOC as its doc string.
51 MAPS, if non-nil, should be a keymap or a list of keymaps; add
52 the submenu defined by MENU to the keymap or each of the keymaps,
53 as a top-level menu bar item.
55 The first element of MENU must be a string. It is the menu bar
56 item name. It may be followed by the following keyword argument
57 pairs:
59 :filter FUNCTION
60 FUNCTION must be a function which, if called with one
61 argument---the list of the other menu items---returns the
62 items to actually display.
64 :visible INCLUDE
65 INCLUDE is an expression. The menu is visible if the
66 expression evaluates to a non-nil value. `:included' is an
67 alias for `:visible'.
69 :active ENABLE
70 ENABLE is an expression. The menu is enabled for selection
71 if the expression evaluates to a non-nil value. `:enable' is
72 an alias for `:active'.
74 The rest of the elements in MENU are menu items.
75 A menu item can be a vector of three elements:
77 [NAME CALLBACK ENABLE]
79 NAME is a string--the menu item name.
81 CALLBACK is a command to run when the item is chosen, or an
82 expression to evaluate when the item is chosen.
84 ENABLE is an expression; the item is enabled for selection if the
85 expression evaluates to a non-nil value.
87 Alternatively, a menu item may have the form:
89 [ NAME CALLBACK [ KEYWORD ARG ]... ]
91 where NAME and CALLBACK have the same meanings as above, and each
92 optional KEYWORD and ARG pair should be one of the following:
94 :keys KEYS
95 KEYS is a string; a keyboard equivalent to the menu item.
96 This is normally not needed because keyboard equivalents are
97 usually computed automatically. KEYS is expanded with
98 `substitute-command-keys' before it is used.
100 :key-sequence KEYS
101 KEYS is a hint for speeding up Emacs's first display of the
102 menu. It should be nil if you know that the menu item has no
103 keyboard equivalent; otherwise it should be a string or
104 vector specifying a keyboard equivalent for the menu item.
106 :active ENABLE
107 ENABLE is an expression; the item is enabled for selection
108 whenever this expression's value is non-nil. `:enable' is an
109 alias for `:active'.
111 :visible INCLUDE
112 INCLUDE is an expression; this item is only visible if this
113 expression has a non-nil value. `:included' is an alias for
114 `:visible'.
116 :label FORM
117 FORM is an expression that is dynamically evaluated and whose
118 value serves as the menu item's label (the default is NAME).
120 :suffix FORM
121 FORM is an expression that is dynamically evaluated and whose
122 value is concatenated with the menu entry's label.
124 :style STYLE
125 STYLE is a symbol describing the type of menu item; it should
126 be `toggle' (a checkbox), or `radio' (a radio button), or any
127 other value (meaning an ordinary menu item).
129 :selected SELECTED
130 SELECTED is an expression; the checkbox or radio button is
131 selected whenever the expression's value is non-nil.
133 :help HELP
134 HELP is a string, the help to display for the menu item.
136 Alternatively, a menu item can be a string. Then that string
137 appears in the menu as unselectable text. A string consisting
138 solely of dashes is displayed as a menu separator.
140 Alternatively, a menu item can be a list with the same format as
141 MENU. This is a submenu."
148 "Return a binding suitable to pass to `define-key'.
149 This is expected to be bound to a mouse event."
150 ;; Under Emacs this is almost trivial, whereas under XEmacs this may
151 ;; involve defining a function that calls popup-menu.
165 ;;;###autoload
167 ;; We can't do anything that might differ between Emacs dialects in
168 ;; `easy-menu-define' in order to make byte compiled files
169 ;; compatible. Therefore everything interesting is done in this
170 ;; function.
176 ;; FIXME: XEmacs uses popup-menu which calls the binding
177 ;; while x-popup-menu only returns the selection.
192 "Convert MENU to the right thing to return from a menu filter.
193 MENU is a menu as computed by `easy-menu-define' or `easy-menu-create-menu' or
194 a symbol whose value is such a menu.
195 In Emacs a menu filter must return a menu (a keymap), in XEmacs a filter must
196 return a menu items list (without menu name and keywords).
197 This function returns the right thing in the two cases.
198 If NAME is provided, it is used for the keymap."
201 ;; If it's a cons but not a keymap, then it can't be right
202 ;; unless it's an XEmacs menu.
205 ;; It's just a menu entry.
207 menu)
210 "Dynamically scoped var to register already used keys in a menu.
211 If it holds a list, this is expected to be a list of keys already seen in the
214 ;;;###autoload
216 "Create a menu called MENU-NAME with items described in MENU-ITEMS.
217 MENU-NAME is a string, the name of the menu. MENU-ITEMS is a list of items
218 possibly preceded by keyword pairs as described in `easy-menu-define'."
221 prop keyword label enable filter visible help)
222 ;; Look for keywords.
229 (`:filter
232 menu-name))))
238 nil ; Invisible menu entry, return nil.
247 ;; The filter expects the menu in its XEmacs form and the
248 ;; pre-filter form will only be passed to the filter
249 ;; anyway, so we'd better not convert it at all (it will
250 ;; be converted on the fly by easy-menu-filter-return).
251 menu-items
256 menu)))
259 ;; Known button types.
266 "Memoize the value returned by `easy-menu-convert-item-1' called on ITEM.
267 This makes key-shortcut-caching work a *lot* better when this
268 conversion is done from within a filter.
269 This also helps when the NAME of the entry is recreated each time:
270 since the menu is built and traversed separately, the lookup
271 would always fail because the key is `equal' but not `eq'."
276 ;; Merging multiple entries with the same name is sometimes what we
277 ;; want, but not when the entries are actually different (e.g. same
278 ;; name but different :suffix as seen in cal-menu.el) and appear in
279 ;; the same menu. So we try to detect and resolve conflicts.
281 ;; We need to use some distinct object, ideally a symbol, ideally
282 ;; related to the `name'. Uninterned symbols do not work (they
283 ;; are apparently turned into strings and re-interned later on).
290 result))
293 "Parse an item description and convert it to a menu keymap element.
294 ITEM defines an item as in `easy-menu-define'."
305 ;; Invisible menu item. Don't insert into keymap.
316 cache cache-specified)
321 keyword arg suffix visible style selected keys)
355 keys)
372 ;; Invisible menu item. Don't insert into keymap.
381 ;; `intern' the name so as to merge multiple entries with the same name.
382 ;; It also makes it easier/possible to lookup/change menu bindings
383 ;; via keymap functions.
393 "Add binding in MENU for KEY => ITEM. Similar to `define-key-after'.
394 If KEY is not nil then delete any duplications.
395 If ITEM is nil, then delete the definition of KEY.
397 Optional argument BEFORE is nil or a key in MENU. If BEFORE is not nil,
398 put binding before the item in MENU named BEFORE; otherwise,
399 if a binding for KEY is already present in MENU, just change it;
400 otherwise put the new binding last in MENU.
401 BEFORE can be either a string (menu item name) or a symbol
402 \(the fake function key for the menu item).
403 KEY does not have to be a symbol, and comparison is done with equal."
406 tail done)
411 ;; If key is nil, stop here, otherwise keep going past the
412 ;; inserted element so we can delete any duplications that come
413 ;; later.
434 "Return t if NAME is the name of menu item ITEM.
435 NAME can be either a string, or a symbol.
436 ITEM should be a keymap binding of the form (KEY . MENU-ITEM)."
441 ;; Match against the text that is displayed to the user.
444 ;; Also check the string version of the symbol name,
445 ;; for backwards compatibility.
449 "Return true if form X never evaluates to nil."
456 "Return a unique symbol with CALLBACK as function value.
457 When non-nil, NOEXP indicates that CALLBACK cannot be an expression
458 \(i.e. does not need to be turned into a function)."
464 ;; `functionp' is probably not needed.
466 callback
468 command))
470 ;;;###autoload
472 "Change menu found at PATH as item NAME to contain ITEMS.
473 PATH is a list of strings for locating the menu that
474 should contain a submenu named NAME.
475 ITEMS is a list of menu items, as in `easy-menu-define'.
476 These items entirely replace the previous items in that submenu.
478 If MAP is specified, it should normally be a keymap; nil stands for the local
479 menu-bar keymap. It can also be a symbol, which has earlier been used as the
480 first argument in a call to `easy-menu-define', or the value of such a symbol.
482 If the menu located by PATH has no submenu named NAME, add one.
483 If the optional argument BEFORE is present, add it just before
484 the submenu named BEFORE, otherwise add it at the end of the menu.
486 To implement dynamic menus, either call this from
487 `menu-bar-update-hook' or use a menu filter."
490 ;; XEmacs needs the following two functions to add and remove menus.
491 ;; In Emacs this is done automatically when switching keymaps, so
492 ;; here easy-menu-remove and easy-menu-add are a noops.
494 "Remove MENU from the current menu bar.
495 Contrary to XEmacs, this is a nop on Emacs since menus are automatically
496 \(de)activated when the corresponding keymap is (de)activated.
501 "Add the menu to the menubar.
502 On Emacs this is a nop, because menus are already automatically
503 activated when the corresponding keymap is activated. On XEmacs
504 this is needed to actually add the menu to the current menubar.
506 You should call this once the menu and keybindings are set up
507 completely and menu filter functions can be expected to work.
512 "Add submenu SUBMENU in the menu at MENU-PATH.
513 If BEFORE is non-nil, add before the item named BEFORE.
514 If IN-MENU is non-nil, follow MENU-PATH in IN-MENU.
515 This is a compatibility function; use `easy-menu-add-item'."
518 submenu before))
521 "To the submenu of MAP with path PATH, add ITEM.
523 If an item with the same name is already present in this submenu,
524 then ITEM replaces it. Otherwise, ITEM is added to this submenu.
525 In the latter case, ITEM is normally added at the end of the submenu.
526 However, if BEFORE is a string and there is an item in the submenu
527 with that name, then ITEM is added before that item.
529 MAP should normally be a keymap; nil stands for the local menu-bar keymap.
530 It can also be a symbol, which has earlier been used as the first
531 argument in a call to `easy-menu-define', or the value of such a symbol.
533 PATH is a list of strings for locating the submenu where ITEM is to be
534 added. If PATH is nil, MAP itself is used. Otherwise, the first
535 element should be the name of a submenu directly under MAP. This
536 submenu is then traversed recursively with the remaining elements of PATH.
538 ITEM is either defined as in `easy-menu-define' or a non-nil value returned
539 by `easy-menu-item-present-p' or `easy-menu-remove-item' or a menu defined
540 earlier by `easy-menu-define' or `easy-menu-create-menu'."
546 ;; This is a value returned by `easy-menu-item-present-p' or
547 ;; `easy-menu-remove-item'.
553 ;; Item is a keymap, find the prompt string and use as item name.
559 "In submenu of MAP with path PATH, return non-nil if item NAME is present.
560 MAP and PATH are defined as in `easy-menu-add-item'.
561 NAME should be a string, the name of the element to be looked for."
565 "From submenu of MAP with path PATH remove item NAME.
566 MAP and PATH are defined as in `easy-menu-add-item'.
567 NAME should be a string, the name of the element to be removed."
571 ret))
574 "In menu MENU try to look for menu item with name NAME.
575 If a menu item is found, return (NAME . item), otherwise return nil.
576 If item is an old format item, a new format item is returned."
577 ;; The call to `lookup-key' also calls the C function `get_keyelt' which
578 ;; looks inside a menu-item to only return the actual command. This is
579 ;; not what we want here. We should either add an arg to lookup-key to be
580 ;; able to turn off this "feature", or else we could use map-keymap here.
581 ;; In the mean time, I just use `assq' which is an OK approximation since
582 ;; menus are rarely built from vectors or char-tables.
585 ret enable cache label)
588 ;; This is the old menu format. Convert it to new format.
603 )))
606 "Lookup menu item NAME in keymap MAP.
607 Like `lookup-key' except that NAME is not an array but just a single key
608 and that NAME can be a string representing the menu item's name."
611 ;; `lookup-key' failed and we have a menu item name: look at the
612 ;; actual menu entries's names.
617 ;; Found it!! Look for it again with
618 ;; `lookup-key' so as to handle inheritance and
619 ;; to extract the actual command/keymap bound to
620 ;; `name' from the item (via get_keyelt).
622 map)))))
625 "Return a sparse keymap in which to add or remove an item.
626 MAP and PATH are as defined in `easy-menu-add-item'.
628 TO-MODIFY, if non-nil, is the name of the item the caller
629 wants to modify in the map that we return.
630 In some cases we use that to select between the local and global maps."
637 ;; Look for PATH in each map.
643 map name))
645 maps))))
647 ;; Prefer a map that already contains the to-be-modified entry.
652 ;; Use the first valid map.
655 ;; Otherwise, make one up.
656 ;; Hardcoding current-local-map is lame, but it's difficult
657 ;; to know what the caller intended for us to do ;-(
663 newmap))))
665 map)
669 ;;; easymenu.el ends here