2 @c This is part of the GNU Emacs Lisp Reference Manual.
3 @c Copyright (C) 1990, 1991, 1992, 1993, 1994, 1998, 1999, 2000, 2002, 2003,
4 @c 2004, 2005, 2006 Free Software Foundation, Inc.
5 @c See the file elisp.texi for copying conditions.
6 @setfilename ../info/keymaps
7 @node Keymaps, Modes, Command Loop, Top
11 The bindings between input events and commands are recorded in data
12 structures called @dfn{keymaps}. Each binding in a keymap associates
13 (or @dfn{binds}) an individual event type, either to another keymap or to
14 a command. When an event type is bound to a keymap, that keymap is used
15 to look up the next input event; this continues until a command is
16 found. The whole process is called @dfn{key lookup}.
19 * Keymap Terminology:: Definitions of terms pertaining to keymaps.
20 * Format of Keymaps:: What a keymap looks like as a Lisp object.
21 * Creating Keymaps:: Functions to create and copy keymaps.
22 * Inheritance and Keymaps:: How one keymap can inherit the bindings
24 * Prefix Keys:: Defining a key with a keymap as its definition.
25 * Active Keymaps:: How Emacs searches the active keymaps
27 * Searching Keymaps:: A pseudo-Lisp summary of searching active maps.
28 * Controlling Active Maps:: Each buffer has a local keymap
29 to override the standard (global) bindings.
30 A minor mode can also override them.
31 * Key Lookup:: Finding a key's binding in one keymap.
32 * Functions for Key Lookup:: How to request key lookup.
33 * Changing Key Bindings:: Redefining a key in a keymap.
34 * Remapping Commands:: Bindings that translate one command to another.
35 * Key Binding Commands:: Interactive interfaces for redefining keys.
36 * Scanning Keymaps:: Looking through all keymaps, for printing help.
37 * Menu Keymaps:: Defining a menu as a keymap.
40 @node Keymap Terminology
41 @section Keymap Terminology
45 @cindex binding of a key
49 A @dfn{keymap} is a table mapping event types to definitions (which
50 can be any Lisp objects, though only certain types are meaningful for
51 execution by the command loop). Given an event (or an event type) and a
52 keymap, Emacs can get the event's definition. Events include
53 characters, function keys, and mouse actions (@pxref{Input Events}).
55 A sequence of input events that form a unit is called a
56 @dfn{key sequence}, or @dfn{key} for short. A sequence of one event
57 is always a key sequence, and so are some multi-event sequences.
59 A keymap determines a binding or definition for any key sequence. If
60 the key sequence is a single event, its binding is the definition of the
61 event in the keymap. The binding of a key sequence of more than one
62 event is found by an iterative process: the binding of the first event
63 is found, and must be a keymap; then the second event's binding is found
64 in that keymap, and so on until all the events in the key sequence are
67 If the binding of a key sequence is a keymap, we call the key sequence
68 a @dfn{prefix key}. Otherwise, we call it a @dfn{complete key} (because
69 no more events can be added to it). If the binding is @code{nil},
70 we call the key @dfn{undefined}. Examples of prefix keys are @kbd{C-c},
71 @kbd{C-x}, and @kbd{C-x 4}. Examples of defined complete keys are
72 @kbd{X}, @key{RET}, and @kbd{C-x 4 C-f}. Examples of undefined complete
73 keys are @kbd{C-x C-g}, and @kbd{C-c 3}. @xref{Prefix Keys}, for more
76 The rule for finding the binding of a key sequence assumes that the
77 intermediate bindings (found for the events before the last) are all
78 keymaps; if this is not so, the sequence of events does not form a
79 unit---it is not really one key sequence. In other words, removing one
80 or more events from the end of any valid key sequence must always yield
81 a prefix key. For example, @kbd{C-f C-n} is not a key sequence;
82 @kbd{C-f} is not a prefix key, so a longer sequence starting with
83 @kbd{C-f} cannot be a key sequence.
85 The set of possible multi-event key sequences depends on the bindings
86 for prefix keys; therefore, it can be different for different keymaps,
87 and can change when bindings are changed. However, a one-event sequence
88 is always a key sequence, because it does not depend on any prefix keys
89 for its well-formedness.
91 At any time, several primary keymaps are @dfn{active}---that is, in
92 use for finding key bindings. These are the @dfn{global map}, which is
93 shared by all buffers; the @dfn{local keymap}, which is usually
94 associated with a specific major mode; and zero or more @dfn{minor mode
95 keymaps}, which belong to currently enabled minor modes. (Not all minor
96 modes have keymaps.) The local keymap bindings shadow (i.e., take
97 precedence over) the corresponding global bindings. The minor mode
98 keymaps shadow both local and global keymaps. @xref{Active Keymaps},
101 The Emacs Lisp representation for a key sequence is a string or vector.
102 You can enter key sequence constants using the ordinary string or vector
103 representation; it is also convenient to use @code{kbd}:
105 @defmac kbd keyseq-text
106 This macro converts the text @var{keyseq-text} (a string constant)
107 into a key sequence (a string or vector constant). The contents
108 of @var{keyseq-text} should describe the key sequence using the syntax
109 used in this manual. More precisely, it uses the same syntax that
110 Edit Macro mode uses for editing keyboard macros (@pxref{Edit Keyboard
111 Macro,,, emacs, The GNU Emacs Manual}).
114 (kbd "C-x") @result{} "\C-x"
115 (kbd "C-x C-f") @result{} "\C-x\C-f"
116 (kbd "C-x 4 C-f") @result{} "\C-x4\C-f"
117 (kbd "X") @result{} "X"
118 (kbd "RET") @result{} "\^M"
119 (kbd "C-c SPC") @result{} "\C-c@ "
120 (kbd "<f1> SPC") @result{} [f1 32]
121 (kbd "C-M-<down>") @result{} [C-M-down]
125 @node Format of Keymaps
126 @section Format of Keymaps
127 @cindex format of keymaps
128 @cindex keymap format
130 @cindex sparse keymap
132 A keymap is a list whose @sc{car} is the symbol @code{keymap}. The
133 remaining elements of the list define the key bindings of the keymap.
134 A symbol whose function definition is a keymap is also a keymap. Use
135 the function @code{keymapp} (see below) to test whether an object is a
138 Several kinds of elements may appear in a keymap, after the symbol
139 @code{keymap} that begins it:
142 @item (@var{type} .@: @var{binding})
143 This specifies one binding, for events of type @var{type}. Each
144 ordinary binding applies to events of a particular @dfn{event type},
145 which is always a character or a symbol. @xref{Classifying Events}.
147 @item (t .@: @var{binding})
148 @cindex default key binding
149 This specifies a @dfn{default key binding}; any event not bound by other
150 elements of the keymap is given @var{binding} as its binding. Default
151 bindings allow a keymap to bind all possible event types without having
152 to enumerate all of them. A keymap that has a default binding
153 completely masks any lower-precedence keymap, except for events
154 explicitly bound to @code{nil} (see below).
156 @item @var{char-table}
157 If an element of a keymap is a char-table, it counts as holding
158 bindings for all character events with no modifier bits
159 (@pxref{modifier bits}): element @var{n} is the binding for the
160 character with code @var{n}. This is a compact way to record lots of
161 bindings. A keymap with such a char-table is called a @dfn{full
162 keymap}. Other keymaps are called @dfn{sparse keymaps}.
165 @cindex keymap prompt string
166 @cindex overall prompt string
167 @cindex prompt string of keymap
168 Aside from bindings, a keymap can also have a string as an element.
169 This is called the @dfn{overall prompt string} and makes it possible to
170 use the keymap as a menu. @xref{Defining Menus}.
173 When the binding is @code{nil}, it doesn't constitute a definition
174 but it does take precedence over a default binding or a binding in the
175 parent keymap. On the other hand, a binding of @code{nil} does
176 @emph{not} override lower-precedence keymaps; thus, if the local map
177 gives a binding of @code{nil}, Emacs uses the binding from the
180 @cindex meta characters lookup
181 Keymaps do not directly record bindings for the meta characters.
182 Instead, meta characters are regarded for purposes of key lookup as
183 sequences of two characters, the first of which is @key{ESC} (or
184 whatever is currently the value of @code{meta-prefix-char}). Thus, the
185 key @kbd{M-a} is internally represented as @kbd{@key{ESC} a}, and its
186 global binding is found at the slot for @kbd{a} in @code{esc-map}
187 (@pxref{Prefix Keys}).
189 This conversion applies only to characters, not to function keys or
190 other input events; thus, @kbd{M-@key{end}} has nothing to do with
191 @kbd{@key{ESC} @key{end}}.
193 Here as an example is the local keymap for Lisp mode, a sparse
194 keymap. It defines bindings for @key{DEL} and @key{TAB}, plus @kbd{C-c
195 C-l}, @kbd{M-C-q}, and @kbd{M-C-x}.
210 ;; @r{@kbd{M-C-x}, treated as @kbd{@key{ESC} C-x}}
211 (24 . lisp-send-defun)
213 ;; @r{@kbd{M-C-q}, treated as @kbd{@key{ESC} C-q}}
217 ;; @r{This part is inherited from @code{lisp-mode-shared-map}.}
220 (127 . backward-delete-char-untabify)
224 ;; @r{@kbd{M-C-q}, treated as @kbd{@key{ESC} C-q}}
226 (9 . lisp-indent-line))
230 @defun keymapp object
231 This function returns @code{t} if @var{object} is a keymap, @code{nil}
232 otherwise. More precisely, this function tests for a list whose
233 @sc{car} is @code{keymap}, or for a symbol whose function definition
234 satisfies @code{keymapp}.
242 (fset 'foo '(keymap))
247 (keymapp (current-global-map))
253 @node Creating Keymaps
254 @section Creating Keymaps
255 @cindex creating keymaps
257 Here we describe the functions for creating keymaps.
259 @defun make-sparse-keymap &optional prompt
260 This function creates and returns a new sparse keymap with no entries.
261 (A sparse keymap is the kind of keymap you usually want.) The new
262 keymap does not contain a char-table, unlike @code{make-keymap}, and
263 does not bind any events.
272 If you specify @var{prompt}, that becomes the overall prompt string for
273 the keymap. The prompt string should be provided for menu keymaps
274 (@pxref{Defining Menus}).
277 @defun make-keymap &optional prompt
278 This function creates and returns a new full keymap. That keymap
279 contains a char-table (@pxref{Char-Tables}) with slots for all
280 characters without modifiers. The new keymap initially binds all
281 these characters to @code{nil}, and does not bind any other kind of
282 event. The argument @var{prompt} specifies a
283 prompt string, as in @code{make-sparse-keymap}.
288 @result{} (keymap #^[t nil nil nil @dots{} nil nil keymap])
292 A full keymap is more efficient than a sparse keymap when it holds
293 lots of bindings; for just a few, the sparse keymap is better.
296 @defun copy-keymap keymap
297 This function returns a copy of @var{keymap}. Any keymaps that
298 appear directly as bindings in @var{keymap} are also copied recursively,
299 and so on to any number of levels. However, recursive copying does not
300 take place when the definition of a character is a symbol whose function
301 definition is a keymap; the same symbol appears in the new copy.
306 (setq map (copy-keymap (current-local-map)))
310 ;; @r{(This implements meta characters.)}
312 (83 . center-paragraph)
314 (9 . tab-to-tab-stop))
318 (eq map (current-local-map))
322 (equal map (current-local-map))
328 @node Inheritance and Keymaps
329 @section Inheritance and Keymaps
330 @cindex keymap inheritance
331 @cindex inheriting a keymap's bindings
333 A keymap can inherit the bindings of another keymap, which we call the
334 @dfn{parent keymap}. Such a keymap looks like this:
337 (keymap @var{bindings}@dots{} . @var{parent-keymap})
341 The effect is that this keymap inherits all the bindings of
342 @var{parent-keymap}, whatever they may be at the time a key is looked up,
343 but can add to them or override them with @var{bindings}.
345 If you change the bindings in @var{parent-keymap} using @code{define-key}
346 or other key-binding functions, these changes are visible in the
347 inheriting keymap unless shadowed by @var{bindings}. The converse is
348 not true: if you use @code{define-key} to change the inheriting keymap,
349 that affects @var{bindings}, but has no effect on @var{parent-keymap}.
351 The proper way to construct a keymap with a parent is to use
352 @code{set-keymap-parent}; if you have code that directly constructs a
353 keymap with a parent, please convert the program to use
354 @code{set-keymap-parent} instead.
356 @defun keymap-parent keymap
357 This returns the parent keymap of @var{keymap}. If @var{keymap}
358 has no parent, @code{keymap-parent} returns @code{nil}.
361 @defun set-keymap-parent keymap parent
362 This sets the parent keymap of @var{keymap} to @var{parent}, and returns
363 @var{parent}. If @var{parent} is @code{nil}, this function gives
364 @var{keymap} no parent at all.
366 If @var{keymap} has submaps (bindings for prefix keys), they too receive
367 new parent keymaps that reflect what @var{parent} specifies for those
371 Here is an example showing how to make a keymap that inherits
372 from @code{text-mode-map}:
375 (let ((map (make-sparse-keymap)))
376 (set-keymap-parent map text-mode-map)
380 A non-sparse keymap can have a parent too, but this is not very
381 useful. A non-sparse keymap always specifies something as the binding
382 for every numeric character code without modifier bits, even if it is
383 @code{nil}, so these character's bindings are never inherited from
390 A @dfn{prefix key} is a key sequence whose binding is a keymap. The
391 keymap defines what to do with key sequences that extend the prefix key.
392 For example, @kbd{C-x} is a prefix key, and it uses a keymap that is
393 also stored in the variable @code{ctl-x-map}. This keymap defines
394 bindings for key sequences starting with @kbd{C-x}.
396 Some of the standard Emacs prefix keys use keymaps that are
397 also found in Lisp variables:
403 @code{esc-map} is the global keymap for the @key{ESC} prefix key. Thus,
404 the global definitions of all meta characters are actually found here.
405 This map is also the function definition of @code{ESC-prefix}.
409 @code{help-map} is the global keymap for the @kbd{C-h} prefix key.
413 @vindex mode-specific-map
414 @code{mode-specific-map} is the global keymap for the prefix key
415 @kbd{C-c}. This map is actually global, not mode-specific, but its name
416 provides useful information about @kbd{C-c} in the output of @kbd{C-h b}
417 (@code{display-bindings}), since the main use of this prefix key is for
418 mode-specific bindings.
423 @findex Control-X-prefix
424 @code{ctl-x-map} is the global keymap used for the @kbd{C-x} prefix key.
425 This map is found via the function cell of the symbol
426 @code{Control-X-prefix}.
429 @cindex @kbd{C-x @key{RET}}
431 @code{mule-keymap} is the global keymap used for the @kbd{C-x @key{RET}}
437 @code{ctl-x-4-map} is the global keymap used for the @kbd{C-x 4} prefix
444 @code{ctl-x-5-map} is the global keymap used for the @kbd{C-x 5} prefix
451 @code{2C-mode-map} is the global keymap used for the @kbd{C-x 6} prefix
456 @vindex vc-prefix-map
457 @code{vc-prefix-map} is the global keymap used for the @kbd{C-x v} prefix
462 @vindex facemenu-keymap
463 @code{facemenu-keymap} is the global keymap used for the @kbd{M-o}
468 The other Emacs prefix keys are @kbd{M-g}, @kbd{C-x @@}, @kbd{C-x a i},
469 @kbd{C-x @key{ESC}} and @kbd{@key{ESC} @key{ESC}}. They use keymaps
470 that have no special names.
473 The keymap binding of a prefix key is used for looking up the event
474 that follows the prefix key. (It may instead be a symbol whose function
475 definition is a keymap. The effect is the same, but the symbol serves
476 as a name for the prefix key.) Thus, the binding of @kbd{C-x} is the
477 symbol @code{Control-X-prefix}, whose function cell holds the keymap
478 for @kbd{C-x} commands. (The same keymap is also the value of
481 Prefix key definitions can appear in any active keymap. The
482 definitions of @kbd{C-c}, @kbd{C-x}, @kbd{C-h} and @key{ESC} as prefix
483 keys appear in the global map, so these prefix keys are always
484 available. Major and minor modes can redefine a key as a prefix by
485 putting a prefix key definition for it in the local map or the minor
486 mode's map. @xref{Active Keymaps}.
488 If a key is defined as a prefix in more than one active map, then its
489 various definitions are in effect merged: the commands defined in the
490 minor mode keymaps come first, followed by those in the local map's
491 prefix definition, and then by those from the global map.
493 In the following example, we make @kbd{C-p} a prefix key in the local
494 keymap, in such a way that @kbd{C-p} is identical to @kbd{C-x}. Then
495 the binding for @kbd{C-p C-f} is the function @code{find-file}, just
496 like @kbd{C-x C-f}. The key sequence @kbd{C-p 6} is not found in any
501 (use-local-map (make-sparse-keymap))
505 (local-set-key "\C-p" ctl-x-map)
509 (key-binding "\C-p\C-f")
514 (key-binding "\C-p6")
519 @defun define-prefix-command symbol &optional mapvar prompt
520 @cindex prefix command
521 @anchor{Definition of define-prefix-command}
522 This function prepares @var{symbol} for use as a prefix key's binding:
523 it creates a sparse keymap and stores it as @var{symbol}'s function
524 definition. Subsequently binding a key sequence to @var{symbol} will
525 make that key sequence into a prefix key. The return value is @code{symbol}.
527 This function also sets @var{symbol} as a variable, with the keymap as
528 its value. But if @var{mapvar} is non-@code{nil}, it sets @var{mapvar}
529 as a variable instead.
531 If @var{prompt} is non-@code{nil}, that becomes the overall prompt
532 string for the keymap. The prompt string should be given for menu keymaps
533 (@pxref{Defining Menus}).
537 @section Active Keymaps
538 @cindex active keymap
539 @cindex global keymap
542 Emacs normally contains many keymaps; at any given time, just a few
543 of them are @dfn{active}, meaning that they participate in the
544 interpretation of user input. All the active keymaps are used
545 together to determine what command to execute when a key is entered.
546 Emacs searches these keymaps one by one, in a standard order, until it
547 finds a binding in one of the keymaps.
549 Normally the active keymaps are the @code{keymap} property keymap,
550 the keymaps of any enabled minor modes, the current buffer's local
551 keymap, and the global keymap, in that order. Therefore, Emacs
552 searches for each input key sequence in all these keymaps. Here is a
553 pseudo-Lisp description of how this process works:
556 (or (if overriding-terminal-local-map
557 (@var{find-in} overriding-terminal-local-map)
558 (if overriding-local-map
559 (@var{find-in} overriding-local-map)
560 (or (@var{find-in} (get-text-property (point) 'keymap))
561 (@var{find-in-any} emulation-mode-map-alists)
562 (@var{find-in-any} minor-mode-overriding-map-alist)
563 (@var{find-in-any} minor-mode-map-alist)
564 (if (get-text-property (point) 'local-map)
565 (@var{find-in} (get-text-property (point) 'local-map))
566 (@var{find-in} (current-local-map))))))
567 (@var{find-in} (current-global-map)))
571 Here, the pseudo-function @var{find-in} means to look up the key
572 sequence in a single map, and @var{find-in-any} means to search the
573 appropriate keymaps from an alist. (Searching a single keymap for a
574 binding is called @dfn{key lookup}; see @ref{Key Lookup}.)
576 The @dfn{global keymap} holds the bindings of keys that are defined
577 regardless of the current buffer, such as @kbd{C-f}. The variable
578 @code{global-map} holds this keymap, which is always active.
580 Each buffer may have another keymap, its @dfn{local keymap}, which
581 may contain new or overriding definitions for keys. The current
582 buffer's local keymap is always active except when
583 @code{overriding-local-map} overrides it. The @code{local-map} text
584 or overlay property can specify an alternative local keymap for certain
585 parts of the buffer; see @ref{Special Properties}.
587 Each minor mode can have a keymap; if it does, the keymap is active
588 when the minor mode is enabled. Modes for emulation can specify
589 additional active keymaps through the variable
590 @code{emulation-mode-map-alists}.
592 The highest precedence normal keymap comes from the @code{keymap}
593 text or overlay property. If that is non-@code{nil}, it is the first
594 keymap to be processed, in normal circumstances.
596 However, there are also special ways for programs to substitute
597 other keymaps for some of those. The variable
598 @code{overriding-local-map}, if non-@code{nil}, specifies a keymap
599 that replaces all the usual active keymaps except the global keymap.
600 Another way to do this is with @code{overriding-terminal-local-map};
601 it operates on a per-terminal basis. These variables are documented
604 @cindex major mode keymap
605 Since every buffer that uses the same major mode normally uses the
606 same local keymap, you can think of the keymap as local to the mode. A
607 change to the local keymap of a buffer (using @code{local-set-key}, for
608 example) is seen also in the other buffers that share that keymap.
610 The local keymaps that are used for Lisp mode and some other major
611 modes exist even if they have not yet been used. These local keymaps are
612 the values of variables such as @code{lisp-mode-map}. For most major
613 modes, which are less frequently used, the local keymap is constructed
614 only when the mode is used for the first time in a session.
616 The minibuffer has local keymaps, too; they contain various completion
617 and exit commands. @xref{Intro to Minibuffers}.
619 Emacs has other keymaps that are used in a different way---translating
620 events within @code{read-key-sequence}. @xref{Translating Input}.
622 @xref{Standard Keymaps}, for a list of standard keymaps.
624 @defun current-active-maps &optional olp
625 This returns the list of active keymaps that would be used by the
626 command loop in the current circumstances to look up a key sequence.
627 Normally it ignores @code{overriding-local-map} and
628 @code{overriding-terminal-local-map}, but if @var{olp} is
629 non-@code{nil} then it pays attention to them.
632 @defun key-binding key &optional accept-defaults no-remap
633 This function returns the binding for @var{key} according to the
634 current active keymaps. The result is @code{nil} if @var{key} is
635 undefined in the keymaps.
638 The argument @var{accept-defaults} controls checking for default
639 bindings, as in @code{lookup-key} (above).
641 When commands are remapped (@pxref{Remapping Commands}),
642 @code{key-binding} normally processes command remappings so as to
643 returns the remapped command that will actually be executed. However,
644 if @var{no-remap} is non-@code{nil}, @code{key-binding} ignores
645 remappings and returns the binding directly specified for @var{key}.
647 An error is signaled if @var{key} is not a string or a vector.
651 (key-binding "\C-x\C-f")
657 @node Searching Keymaps
658 @section Searching the Active Keymaps
660 After translation of the input events (@pxref{Translating Input})
661 Emacs looks for them in the active keymaps. Here is a pseudo-Lisp
662 description of the order in which the active keymaps are searched:
665 (or (if overriding-terminal-local-map
666 (@var{find-in} overriding-terminal-local-map)
667 (if overriding-local-map
668 (@var{find-in} overriding-local-map)
669 (or (@var{find-in} (get-text-property (point) 'keymap))
670 (@var{find-in-any} emulation-mode-map-alists)
671 (@var{find-in-any} minor-mode-overriding-map-alist)
672 (@var{find-in-any} minor-mode-map-alist)
673 (if (get-text-property (point) 'local-map)
674 (@var{find-in} (get-text-property (point) 'local-map))
675 (@var{find-in} (current-local-map))))))
676 (@var{find-in} (current-global-map)))
680 The @var{find-in} and @var{find-in-any} are pseudo functions that
681 search in one keymap and in an alist of keymaps, respectively.
685 The function finally found may be remapped
686 (@pxref{Remapping Commands}).
689 Characters that are bound to @code{self-insert-command} are translated
690 according to @code{translation-table-for-input} before insertion.
693 @code{current-active-maps} returns a list of the
694 currently active keymaps at point.
697 When a match is found (@pxref{Key Lookup}), if the binding in the
698 keymap is a function, the search is over. However if the keymap entry
699 is a symbol with a value or a string, Emacs replaces the input key
700 sequences with the variable's value or the string, and restarts the
701 search of the active keymaps.
704 @node Controlling Active Maps
705 @section Controlling the Active Keymaps
708 This variable contains the default global keymap that maps Emacs
709 keyboard input to commands. The global keymap is normally this
710 keymap. The default global keymap is a full keymap that binds
711 @code{self-insert-command} to all of the printing characters.
713 It is normal practice to change the bindings in the global keymap, but you
714 should not assign this variable any value other than the keymap it starts
718 @defun current-global-map
719 This function returns the current global keymap. This is the
720 same as the value of @code{global-map} unless you change one or the
726 @result{} (keymap [set-mark-command beginning-of-line @dots{}
727 delete-backward-char])
732 @defun current-local-map
733 This function returns the current buffer's local keymap, or @code{nil}
734 if it has none. In the following example, the keymap for the
735 @samp{*scratch*} buffer (using Lisp Interaction mode) is a sparse keymap
736 in which the entry for @key{ESC}, @acronym{ASCII} code 27, is another sparse
743 (10 . eval-print-last-sexp)
744 (9 . lisp-indent-line)
745 (127 . backward-delete-char-untabify)
755 @defun current-minor-mode-maps
756 This function returns a list of the keymaps of currently enabled minor modes.
759 @defun use-global-map keymap
760 This function makes @var{keymap} the new current global keymap. It
763 It is very unusual to change the global keymap.
766 @defun use-local-map keymap
767 This function makes @var{keymap} the new local keymap of the current
768 buffer. If @var{keymap} is @code{nil}, then the buffer has no local
769 keymap. @code{use-local-map} returns @code{nil}. Most major mode
770 commands use this function.
774 @defvar minor-mode-map-alist
775 @anchor{Definition of minor-mode-map-alist}
776 This variable is an alist describing keymaps that may or may not be
777 active according to the values of certain variables. Its elements look
781 (@var{variable} . @var{keymap})
784 The keymap @var{keymap} is active whenever @var{variable} has a
785 non-@code{nil} value. Typically @var{variable} is the variable that
786 enables or disables a minor mode. @xref{Keymaps and Minor Modes}.
788 Note that elements of @code{minor-mode-map-alist} do not have the same
789 structure as elements of @code{minor-mode-alist}. The map must be the
790 @sc{cdr} of the element; a list with the map as the second element will
791 not do. The @sc{cdr} can be either a keymap (a list) or a symbol whose
792 function definition is a keymap.
794 When more than one minor mode keymap is active, the earlier one in
795 @code{minor-mode-map-alist} takes priority. But you should design
796 minor modes so that they don't interfere with each other. If you do
797 this properly, the order will not matter.
799 See @ref{Keymaps and Minor Modes}, for more information about minor
800 modes. See also @code{minor-mode-key-binding} (@pxref{Functions for Key
804 @defvar minor-mode-overriding-map-alist
805 This variable allows major modes to override the key bindings for
806 particular minor modes. The elements of this alist look like the
807 elements of @code{minor-mode-map-alist}: @code{(@var{variable}
810 If a variable appears as an element of
811 @code{minor-mode-overriding-map-alist}, the map specified by that
812 element totally replaces any map specified for the same variable in
813 @code{minor-mode-map-alist}.
815 @code{minor-mode-overriding-map-alist} is automatically buffer-local in
819 @defvar overriding-local-map
820 If non-@code{nil}, this variable holds a keymap to use instead of the
821 buffer's local keymap, any text property or overlay keymaps, and any
822 minor mode keymaps. This keymap, if specified, overrides all other
823 maps that would have been active, except for the current global map.
826 @defvar overriding-terminal-local-map
827 If non-@code{nil}, this variable holds a keymap to use instead of
828 @code{overriding-local-map}, the buffer's local keymap, text property
829 or overlay keymaps, and all the minor mode keymaps.
831 This variable is always local to the current terminal and cannot be
832 buffer-local. @xref{Multiple Displays}. It is used to implement
833 incremental search mode.
836 @defvar overriding-local-map-menu-flag
837 If this variable is non-@code{nil}, the value of
838 @code{overriding-local-map} or @code{overriding-terminal-local-map} can
839 affect the display of the menu bar. The default value is @code{nil}, so
840 those map variables have no effect on the menu bar.
842 Note that these two map variables do affect the execution of key
843 sequences entered using the menu bar, even if they do not affect the
844 menu bar display. So if a menu bar key sequence comes in, you should
845 clear the variables before looking up and executing that key sequence.
846 Modes that use the variables would typically do this anyway; normally
847 they respond to events that they do not handle by ``unreading'' them and
851 @defvar special-event-map
852 This variable holds a keymap for special events. If an event type has a
853 binding in this keymap, then it is special, and the binding for the
854 event is run directly by @code{read-event}. @xref{Special Events}.
857 @defvar emulation-mode-map-alists
858 This variable holds a list of keymap alists to use for emulations
859 modes. It is intended for modes or packages using multiple minor-mode
860 keymaps. Each element is a keymap alist which has the same format and
861 meaning as @code{minor-mode-map-alist}, or a symbol with a variable
862 binding which is such an alist. The ``active'' keymaps in each alist
863 are used before @code{minor-mode-map-alist} and
864 @code{minor-mode-overriding-map-alist}.
872 @dfn{Key lookup} is the process of finding the binding of a key
873 sequence from a given keymap. The execution or use of the binding is
874 not part of key lookup.
876 Key lookup uses just the event type of each event in the key sequence;
877 the rest of the event is ignored. In fact, a key sequence used for key
878 lookup may designate a mouse event with just its types (a symbol)
879 instead of the entire event (a list). @xref{Input Events}. Such
880 a ``key sequence'' is insufficient for @code{command-execute} to run,
881 but it is sufficient for looking up or rebinding a key.
883 When the key sequence consists of multiple events, key lookup
884 processes the events sequentially: the binding of the first event is
885 found, and must be a keymap; then the second event's binding is found in
886 that keymap, and so on until all the events in the key sequence are used
887 up. (The binding thus found for the last event may or may not be a
888 keymap.) Thus, the process of key lookup is defined in terms of a
889 simpler process for looking up a single event in a keymap. How that is
890 done depends on the type of object associated with the event in that
893 Let's use the term @dfn{keymap entry} to describe the value found by
894 looking up an event type in a keymap. (This doesn't include the item
895 string and other extra elements in menu key bindings, because
896 @code{lookup-key} and other key lookup functions don't include them in
897 the returned value.) While any Lisp object may be stored in a keymap as
898 a keymap entry, not all make sense for key lookup. Here is a table of
899 the meaningful kinds of keymap entries:
903 @cindex @code{nil} in keymap
904 @code{nil} means that the events used so far in the lookup form an
905 undefined key. When a keymap fails to mention an event type at all, and
906 has no default binding, that is equivalent to a binding of @code{nil}
910 @cindex command in keymap
911 The events used so far in the lookup form a complete key,
912 and @var{command} is its binding. @xref{What Is a Function}.
915 @cindex string in keymap
916 The array (either a string or a vector) is a keyboard macro. The events
917 used so far in the lookup form a complete key, and the array is its
918 binding. See @ref{Keyboard Macros}, for more information.
921 @cindex keymap in keymap
922 The events used so far in the lookup form a prefix key. The next
923 event of the key sequence is looked up in @var{keymap}.
926 @cindex list in keymap
927 The meaning of a list depends on the types of the elements of the list.
931 If the @sc{car} of @var{list} is the symbol @code{keymap}, then the list
932 is a keymap, and is treated as a keymap (see above).
935 @cindex @code{lambda} in keymap
936 If the @sc{car} of @var{list} is @code{lambda}, then the list is a
937 lambda expression. This is presumed to be a function, and is treated
938 as such (see above). In order to execute properly as a key binding,
939 this function must be a command---it must have an @code{interactive}
940 specification. @xref{Defining Commands}.
943 If the @sc{car} of @var{list} is a keymap and the @sc{cdr} is an event
944 type, then this is an @dfn{indirect entry}:
947 (@var{othermap} . @var{othertype})
950 When key lookup encounters an indirect entry, it looks up instead the
951 binding of @var{othertype} in @var{othermap} and uses that.
953 This feature permits you to define one key as an alias for another key.
954 For example, an entry whose @sc{car} is the keymap called @code{esc-map}
955 and whose @sc{cdr} is 32 (the code for @key{SPC}) means, ``Use the global
956 binding of @kbd{Meta-@key{SPC}}, whatever that may be.''
960 @cindex symbol in keymap
961 The function definition of @var{symbol} is used in place of
962 @var{symbol}. If that too is a symbol, then this process is repeated,
963 any number of times. Ultimately this should lead to an object that is
964 a keymap, a command, or a keyboard macro. A list is allowed if it is a
965 keymap or a command, but indirect entries are not understood when found
968 Note that keymaps and keyboard macros (strings and vectors) are not
969 valid functions, so a symbol with a keymap, string, or vector as its
970 function definition is invalid as a function. It is, however, valid as
971 a key binding. If the definition is a keyboard macro, then the symbol
972 is also valid as an argument to @code{command-execute}
973 (@pxref{Interactive Call}).
975 @cindex @code{undefined} in keymap
976 The symbol @code{undefined} is worth special mention: it means to treat
977 the key as undefined. Strictly speaking, the key is defined, and its
978 binding is the command @code{undefined}; but that command does the same
979 thing that is done automatically for an undefined key: it rings the bell
980 (by calling @code{ding}) but does not signal an error.
982 @cindex preventing prefix key
983 @code{undefined} is used in local keymaps to override a global key
984 binding and make the key ``undefined'' locally. A local binding of
985 @code{nil} would fail to do this because it would not override the
988 @item @var{anything else}
989 If any other type of object is found, the events used so far in the
990 lookup form a complete key, and the object is its binding, but the
991 binding is not executable as a command.
994 In short, a keymap entry may be a keymap, a command, a keyboard macro,
995 a symbol that leads to one of them, or an indirection or @code{nil}.
996 Here is an example of a sparse keymap with two characters bound to
997 commands and one bound to another keymap. This map is the normal value
998 of @code{emacs-lisp-mode-map}. Note that 9 is the code for @key{TAB},
999 127 for @key{DEL}, 27 for @key{ESC}, 17 for @kbd{C-q} and 24 for
1004 (keymap (9 . lisp-indent-line)
1005 (127 . backward-delete-char-untabify)
1006 (27 keymap (17 . indent-sexp) (24 . eval-defun)))
1010 @node Functions for Key Lookup
1011 @section Functions for Key Lookup
1013 Here are the functions and variables pertaining to key lookup.
1015 @defun lookup-key keymap key &optional accept-defaults
1016 This function returns the definition of @var{key} in @var{keymap}. All
1017 the other functions described in this chapter that look up keys use
1018 @code{lookup-key}. Here are examples:
1022 (lookup-key (current-global-map) "\C-x\C-f")
1026 (lookup-key (current-global-map) (kbd "C-x C-f"))
1030 (lookup-key (current-global-map) "\C-x\C-f12345")
1035 If the string or vector @var{key} is not a valid key sequence according
1036 to the prefix keys specified in @var{keymap}, it must be ``too long''
1037 and have extra events at the end that do not fit into a single key
1038 sequence. Then the value is a number, the number of events at the front
1039 of @var{key} that compose a complete key.
1042 If @var{accept-defaults} is non-@code{nil}, then @code{lookup-key}
1043 considers default bindings as well as bindings for the specific events
1044 in @var{key}. Otherwise, @code{lookup-key} reports only bindings for
1045 the specific sequence @var{key}, ignoring default bindings except when
1046 you explicitly ask about them. (To do this, supply @code{t} as an
1047 element of @var{key}; see @ref{Format of Keymaps}.)
1049 If @var{key} contains a meta character (not a function key), that
1050 character is implicitly replaced by a two-character sequence: the value
1051 of @code{meta-prefix-char}, followed by the corresponding non-meta
1052 character. Thus, the first example below is handled by conversion into
1057 (lookup-key (current-global-map) "\M-f")
1058 @result{} forward-word
1061 (lookup-key (current-global-map) "\ef")
1062 @result{} forward-word
1066 Unlike @code{read-key-sequence}, this function does not modify the
1067 specified events in ways that discard information (@pxref{Key Sequence
1068 Input}). In particular, it does not convert letters to lower case and
1069 it does not change drag events to clicks.
1072 @deffn Command undefined
1073 Used in keymaps to undefine keys. It calls @code{ding}, but does
1077 @defun local-key-binding key &optional accept-defaults
1078 This function returns the binding for @var{key} in the current
1079 local keymap, or @code{nil} if it is undefined there.
1082 The argument @var{accept-defaults} controls checking for default bindings,
1083 as in @code{lookup-key} (above).
1086 @defun global-key-binding key &optional accept-defaults
1087 This function returns the binding for command @var{key} in the
1088 current global keymap, or @code{nil} if it is undefined there.
1091 The argument @var{accept-defaults} controls checking for default bindings,
1092 as in @code{lookup-key} (above).
1096 @defun minor-mode-key-binding key &optional accept-defaults
1097 This function returns a list of all the active minor mode bindings of
1098 @var{key}. More precisely, it returns an alist of pairs
1099 @code{(@var{modename} . @var{binding})}, where @var{modename} is the
1100 variable that enables the minor mode, and @var{binding} is @var{key}'s
1101 binding in that mode. If @var{key} has no minor-mode bindings, the
1102 value is @code{nil}.
1104 If the first binding found is not a prefix definition (a keymap or a
1105 symbol defined as a keymap), all subsequent bindings from other minor
1106 modes are omitted, since they would be completely shadowed. Similarly,
1107 the list omits non-prefix bindings that follow prefix bindings.
1109 The argument @var{accept-defaults} controls checking for default
1110 bindings, as in @code{lookup-key} (above).
1113 @defvar meta-prefix-char
1115 This variable is the meta-prefix character code. It is used for
1116 translating a meta character to a two-character sequence so it can be
1117 looked up in a keymap. For useful results, the value should be a
1118 prefix event (@pxref{Prefix Keys}). The default value is 27, which is
1119 the @acronym{ASCII} code for @key{ESC}.
1121 As long as the value of @code{meta-prefix-char} remains 27, key lookup
1122 translates @kbd{M-b} into @kbd{@key{ESC} b}, which is normally defined
1123 as the @code{backward-word} command. However, if you were to set
1124 @code{meta-prefix-char} to 24, the code for @kbd{C-x}, then Emacs will
1125 translate @kbd{M-b} into @kbd{C-x b}, whose standard binding is the
1126 @code{switch-to-buffer} command. (Don't actually do this!) Here is an
1127 illustration of what would happen:
1131 meta-prefix-char ; @r{The default value.}
1135 (key-binding "\M-b")
1136 @result{} backward-word
1139 ?\C-x ; @r{The print representation}
1140 @result{} 24 ; @r{of a character.}
1143 (setq meta-prefix-char 24)
1147 (key-binding "\M-b")
1148 @result{} switch-to-buffer ; @r{Now, typing @kbd{M-b} is}
1149 ; @r{like typing @kbd{C-x b}.}
1151 (setq meta-prefix-char 27) ; @r{Avoid confusion!}
1152 @result{} 27 ; @r{Restore the default value!}
1156 This translation of one event into two happens only for characters, not
1157 for other kinds of input events. Thus, @kbd{M-@key{F1}}, a function
1158 key, is not converted into @kbd{@key{ESC} @key{F1}}.
1161 @node Changing Key Bindings
1162 @section Changing Key Bindings
1163 @cindex changing key bindings
1166 The way to rebind a key is to change its entry in a keymap. If you
1167 change a binding in the global keymap, the change is effective in all
1168 buffers (though it has no direct effect in buffers that shadow the
1169 global binding with a local one). If you change the current buffer's
1170 local map, that usually affects all buffers using the same major mode.
1171 The @code{global-set-key} and @code{local-set-key} functions are
1172 convenient interfaces for these operations (@pxref{Key Binding
1173 Commands}). You can also use @code{define-key}, a more general
1174 function; then you must specify explicitly the map to change.
1176 @cindex meta character key constants
1177 @cindex control character key constants
1178 In writing the key sequence to rebind, it is good to use the special
1179 escape sequences for control and meta characters (@pxref{String Type}).
1180 The syntax @samp{\C-} means that the following character is a control
1181 character and @samp{\M-} means that the following character is a meta
1182 character. Thus, the string @code{"\M-x"} is read as containing a
1183 single @kbd{M-x}, @code{"\C-f"} is read as containing a single
1184 @kbd{C-f}, and @code{"\M-\C-x"} and @code{"\C-\M-x"} are both read as
1185 containing a single @kbd{C-M-x}. You can also use this escape syntax in
1186 vectors, as well as others that aren't allowed in strings; one example
1187 is @samp{[?\C-\H-x home]}. @xref{Character Type}.
1189 The key definition and lookup functions accept an alternate syntax for
1190 event types in a key sequence that is a vector: you can use a list
1191 containing modifier names plus one base event (a character or function
1192 key name). For example, @code{(control ?a)} is equivalent to
1193 @code{?\C-a} and @code{(hyper control left)} is equivalent to
1194 @code{C-H-left}. One advantage of such lists is that the precise
1195 numeric codes for the modifier bits don't appear in compiled files.
1197 For the functions below, an error is signaled if @var{keymap} is not
1198 a keymap or if @var{key} is not a string or vector representing a key
1199 sequence. You can use event types (symbols) as shorthand for events
1200 that are lists. The @code{kbd} macro (@pxref{Keymap Terminology}) is
1201 a convenient way to specify the key sequence.
1203 @defun define-key keymap key binding
1204 This function sets the binding for @var{key} in @var{keymap}. (If
1205 @var{key} is more than one event long, the change is actually made
1206 in another keymap reached from @var{keymap}.) The argument
1207 @var{binding} can be any Lisp object, but only certain types are
1208 meaningful. (For a list of meaningful types, see @ref{Key Lookup}.)
1209 The value returned by @code{define-key} is @var{binding}.
1211 If @var{key} is @code{[t]}, this sets the default binding in
1212 @var{keymap}. When an event has no binding of its own, the Emacs
1213 command loop uses the keymap's default binding, if there is one.
1215 @cindex invalid prefix key error
1216 @cindex key sequence error
1217 Every prefix of @var{key} must be a prefix key (i.e., bound to a keymap)
1218 or undefined; otherwise an error is signaled. If some prefix of
1219 @var{key} is undefined, then @code{define-key} defines it as a prefix
1220 key so that the rest of @var{key} can be defined as specified.
1222 If there was previously no binding for @var{key} in @var{keymap}, the
1223 new binding is added at the beginning of @var{keymap}. The order of
1224 bindings in a keymap makes no difference for keyboard input, but it
1225 does matter for menu keymaps (@pxref{Menu Keymaps}).
1228 Here is an example that creates a sparse keymap and makes a number of
1233 (setq map (make-sparse-keymap))
1237 (define-key map "\C-f" 'forward-char)
1238 @result{} forward-char
1242 @result{} (keymap (6 . forward-char))
1246 ;; @r{Build sparse submap for @kbd{C-x} and bind @kbd{f} in that.}
1247 (define-key map (kbd "C-x f") 'forward-word)
1248 @result{} forward-word
1253 (24 keymap ; @kbd{C-x}
1254 (102 . forward-word)) ; @kbd{f}
1255 (6 . forward-char)) ; @kbd{C-f}
1259 ;; @r{Bind @kbd{C-p} to the @code{ctl-x-map}.}
1260 (define-key map (kbd "C-p") ctl-x-map)
1262 @result{} [nil @dots{} find-file @dots{} backward-kill-sentence]
1266 ;; @r{Bind @kbd{C-f} to @code{foo} in the @code{ctl-x-map}.}
1267 (define-key map (kbd "C-p C-f") 'foo)
1272 @result{} (keymap ; @r{Note @code{foo} in @code{ctl-x-map}.}
1273 (16 keymap [nil @dots{} foo @dots{} backward-kill-sentence])
1275 (102 . forward-word))
1281 Note that storing a new binding for @kbd{C-p C-f} actually works by
1282 changing an entry in @code{ctl-x-map}, and this has the effect of
1283 changing the bindings of both @kbd{C-p C-f} and @kbd{C-x C-f} in the
1286 The function @code{substitute-key-definition} scans a keymap for
1287 keys that have a certain binding and rebinds them with a different
1288 binding. Another feature which is cleaner and can often produce the
1289 same results to remap one command into another (@pxref{Remapping
1292 @defun substitute-key-definition olddef newdef keymap &optional oldmap
1293 @cindex replace bindings
1294 This function replaces @var{olddef} with @var{newdef} for any keys in
1295 @var{keymap} that were bound to @var{olddef}. In other words,
1296 @var{olddef} is replaced with @var{newdef} wherever it appears. The
1297 function returns @code{nil}.
1299 For example, this redefines @kbd{C-x C-f}, if you do it in an Emacs with
1304 (substitute-key-definition
1305 'find-file 'find-file-read-only (current-global-map))
1310 If @var{oldmap} is non-@code{nil}, that changes the behavior of
1311 @code{substitute-key-definition}: the bindings in @var{oldmap} determine
1312 which keys to rebind. The rebindings still happen in @var{keymap}, not
1313 in @var{oldmap}. Thus, you can change one map under the control of the
1314 bindings in another. For example,
1317 (substitute-key-definition
1318 'delete-backward-char 'my-funny-delete
1323 puts the special deletion command in @code{my-map} for whichever keys
1324 are globally bound to the standard deletion command.
1326 Here is an example showing a keymap before and after substitution:
1334 @result{} (keymap (49 . olddef-1) (50 . olddef-2) (51 . olddef-1))
1338 (substitute-key-definition 'olddef-1 'newdef map)
1343 @result{} (keymap (49 . newdef) (50 . olddef-2) (51 . newdef))
1348 @defun suppress-keymap keymap &optional nodigits
1349 @cindex @code{self-insert-command} override
1350 This function changes the contents of the full keymap @var{keymap} by
1351 remapping @code{self-insert-command} to the command @code{undefined}
1352 (@pxref{Remapping Commands}). This has the effect of undefining all
1353 printing characters, thus making ordinary insertion of text impossible.
1354 @code{suppress-keymap} returns @code{nil}.
1356 If @var{nodigits} is @code{nil}, then @code{suppress-keymap} defines
1357 digits to run @code{digit-argument}, and @kbd{-} to run
1358 @code{negative-argument}. Otherwise it makes them undefined like the
1359 rest of the printing characters.
1361 @cindex yank suppression
1362 @cindex @code{quoted-insert} suppression
1363 The @code{suppress-keymap} function does not make it impossible to
1364 modify a buffer, as it does not suppress commands such as @code{yank}
1365 and @code{quoted-insert}. To prevent any modification of a buffer, make
1366 it read-only (@pxref{Read Only Buffers}).
1368 Since this function modifies @var{keymap}, you would normally use it
1369 on a newly created keymap. Operating on an existing keymap
1370 that is used for some other purpose is likely to cause trouble; for
1371 example, suppressing @code{global-map} would make it impossible to use
1374 Most often, @code{suppress-keymap} is used to initialize local
1375 keymaps of modes such as Rmail and Dired where insertion of text is not
1376 desirable and the buffer is read-only. Here is an example taken from
1377 the file @file{emacs/lisp/dired.el}, showing how the local keymap for
1378 Dired mode is set up:
1382 (setq dired-mode-map (make-keymap))
1383 (suppress-keymap dired-mode-map)
1384 (define-key dired-mode-map "r" 'dired-rename-file)
1385 (define-key dired-mode-map "\C-d" 'dired-flag-file-deleted)
1386 (define-key dired-mode-map "d" 'dired-flag-file-deleted)
1387 (define-key dired-mode-map "v" 'dired-view-file)
1388 (define-key dired-mode-map "e" 'dired-find-file)
1389 (define-key dired-mode-map "f" 'dired-find-file)
1395 @node Remapping Commands
1396 @section Remapping Commands
1397 @cindex remapping commands
1399 A special kind of key binding, using a special ``key sequence''
1400 which includes a command name, has the effect of @dfn{remapping} that
1401 command into another. Here's how it works. You make a key binding
1402 for a key sequence that starts with the dummy event @code{remap},
1403 followed by the command name you want to remap. Specify the remapped
1404 definition as the definition in this binding. The remapped definition
1405 is usually a command name, but it can be any valid definition for
1408 Here's an example. Suppose that My mode uses special commands
1409 @code{my-kill-line} and @code{my-kill-word}, which should be invoked
1410 instead of @code{kill-line} and @code{kill-word}. It can establish
1411 this by making these two command-remapping bindings in its keymap:
1414 (define-key my-mode-map [remap kill-line] 'my-kill-line)
1415 (define-key my-mode-map [remap kill-word] 'my-kill-word)
1418 Whenever @code{my-mode-map} is an active keymap, if the user types
1419 @kbd{C-k}, Emacs will find the standard global binding of
1420 @code{kill-line} (assuming nobody has changed it). But
1421 @code{my-mode-map} remaps @code{kill-line} to @code{my-kill-line},
1422 so instead of running @code{kill-line}, Emacs runs
1423 @code{my-kill-line}.
1425 Remapping only works through a single level. In other words,
1428 (define-key my-mode-map [remap kill-line] 'my-kill-line)
1429 (define-key my-mode-map [remap my-kill-line] 'my-other-kill-line)
1433 does not have the effect of remapping @code{kill-line} into
1434 @code{my-other-kill-line}. If an ordinary key binding specifies
1435 @code{kill-line}, this keymap will remap it to @code{my-kill-line};
1436 if an ordinary binding specifies @code{my-kill-line}, this keymap will
1437 remap it to @code{my-other-kill-line}.
1439 @defun command-remapping command
1440 This function returns the remapping for @var{command} (a symbol),
1441 given the current active keymaps. If @var{command} is not remapped
1442 (which is the usual situation), or not a symbol, the function returns
1446 @node Key Binding Commands
1447 @section Commands for Binding Keys
1449 This section describes some convenient interactive interfaces for
1450 changing key bindings. They work by calling @code{define-key}.
1452 People often use @code{global-set-key} in their init files
1453 (@pxref{Init File}) for simple customization. For example,
1456 (global-set-key (kbd "C-x C-\\") 'next-line)
1463 (global-set-key [?\C-x ?\C-\\] 'next-line)
1470 (global-set-key [(control ?x) (control ?\\)] 'next-line)
1474 redefines @kbd{C-x C-\} to move down a line.
1477 (global-set-key [M-mouse-1] 'mouse-set-point)
1481 redefines the first (leftmost) mouse button, entered with the Meta key, to
1482 set point where you click.
1484 @cindex non-@acronym{ASCII} text in keybindings
1485 Be careful when using non-@acronym{ASCII} text characters in Lisp
1486 specifications of keys to bind. If these are read as multibyte text, as
1487 they usually will be in a Lisp file (@pxref{Loading Non-ASCII}), you
1488 must type the keys as multibyte too. For instance, if you use this:
1491 (global-set-key "@"o" 'my-function) ; bind o-umlaut
1498 (global-set-key ?@"o 'my-function) ; bind o-umlaut
1502 and your language environment is multibyte Latin-1, these commands
1503 actually bind the multibyte character with code 2294, not the unibyte
1504 Latin-1 character with code 246 (@kbd{M-v}). In order to use this
1505 binding, you need to enter the multibyte Latin-1 character as keyboard
1506 input. One way to do this is by using an appropriate input method
1507 (@pxref{Input Methods, , Input Methods, emacs, The GNU Emacs Manual}).
1509 If you want to use a unibyte character in the key binding, you can
1510 construct the key sequence string using @code{multibyte-char-to-unibyte}
1511 or @code{string-make-unibyte} (@pxref{Converting Representations}).
1513 @deffn Command global-set-key key binding
1514 This function sets the binding of @var{key} in the current global map
1519 (global-set-key @var{key} @var{binding})
1521 (define-key (current-global-map) @var{key} @var{binding})
1526 @deffn Command global-unset-key key
1527 @cindex unbinding keys
1528 This function removes the binding of @var{key} from the current
1531 One use of this function is in preparation for defining a longer key
1532 that uses @var{key} as a prefix---which would not be allowed if
1533 @var{key} has a non-prefix binding. For example:
1537 (global-unset-key "\C-l")
1541 (global-set-key "\C-l\C-l" 'redraw-display)
1546 This function is implemented simply using @code{define-key}:
1550 (global-unset-key @var{key})
1552 (define-key (current-global-map) @var{key} nil)
1557 @deffn Command local-set-key key binding
1558 This function sets the binding of @var{key} in the current local
1559 keymap to @var{binding}.
1563 (local-set-key @var{key} @var{binding})
1565 (define-key (current-local-map) @var{key} @var{binding})
1570 @deffn Command local-unset-key key
1571 This function removes the binding of @var{key} from the current
1576 (local-unset-key @var{key})
1578 (define-key (current-local-map) @var{key} nil)
1583 @node Scanning Keymaps
1584 @section Scanning Keymaps
1586 This section describes functions used to scan all the current keymaps
1587 for the sake of printing help information.
1589 @defun accessible-keymaps keymap &optional prefix
1590 This function returns a list of all the keymaps that can be reached (via
1591 zero or more prefix keys) from @var{keymap}. The value is an
1592 association list with elements of the form @code{(@var{key} .@:
1593 @var{map})}, where @var{key} is a prefix key whose definition in
1594 @var{keymap} is @var{map}.
1596 The elements of the alist are ordered so that the @var{key} increases
1597 in length. The first element is always @code{([] .@: @var{keymap})},
1598 because the specified keymap is accessible from itself with a prefix of
1601 If @var{prefix} is given, it should be a prefix key sequence; then
1602 @code{accessible-keymaps} includes only the submaps whose prefixes start
1603 with @var{prefix}. These elements look just as they do in the value of
1604 @code{(accessible-keymaps)}; the only difference is that some elements
1607 In the example below, the returned alist indicates that the key
1608 @key{ESC}, which is displayed as @samp{^[}, is a prefix key whose
1609 definition is the sparse keymap @code{(keymap (83 .@: center-paragraph)
1614 (accessible-keymaps (current-local-map))
1615 @result{}(([] keymap
1616 (27 keymap ; @r{Note this keymap for @key{ESC} is repeated below.}
1617 (83 . center-paragraph)
1618 (115 . center-line))
1619 (9 . tab-to-tab-stop))
1624 (83 . center-paragraph)
1629 In the following example, @kbd{C-h} is a prefix key that uses a sparse
1630 keymap starting with @code{(keymap (118 . describe-variable)@dots{})}.
1631 Another prefix, @kbd{C-x 4}, uses a keymap which is also the value of
1632 the variable @code{ctl-x-4-map}. The event @code{mode-line} is one of
1633 several dummy events used as prefixes for mouse actions in special parts
1638 (accessible-keymaps (current-global-map))
1639 @result{} (([] keymap [set-mark-command beginning-of-line @dots{}
1640 delete-backward-char])
1643 ("^H" keymap (118 . describe-variable) @dots{}
1644 (8 . help-for-help))
1647 ("^X" keymap [x-flush-mouse-queue @dots{}
1648 backward-kill-sentence])
1651 ("^[" keymap [mark-sexp backward-sexp @dots{}
1652 backward-kill-word])
1654 ("^X4" keymap (15 . display-buffer) @dots{})
1657 (S-mouse-2 . mouse-split-window-horizontally) @dots{}))
1662 These are not all the keymaps you would see in actuality.
1665 @defun map-keymap function keymap
1666 The function @code{map-keymap} calls @var{function} once
1667 for each binding in @var{keymap}. It passes two arguments,
1668 the event type and the value of the binding. If @var{keymap}
1669 has a parent, the parent's bindings are included as well.
1670 This works recursively: if the parent has itself a parent, then the
1671 grandparent's bindings are also included and so on.
1673 This function is the cleanest way to examine all the bindings
1677 @defun where-is-internal command &optional keymap firstonly noindirect no-remap
1678 This function is a subroutine used by the @code{where-is} command
1679 (@pxref{Help, , Help, emacs,The GNU Emacs Manual}). It returns a list
1680 of all key sequences (of any length) that are bound to @var{command} in a
1683 The argument @var{command} can be any object; it is compared with all
1684 keymap entries using @code{eq}.
1686 If @var{keymap} is @code{nil}, then the maps used are the current active
1687 keymaps, disregarding @code{overriding-local-map} (that is, pretending
1688 its value is @code{nil}). If @var{keymap} is a keymap, then the
1689 maps searched are @var{keymap} and the global keymap. If @var{keymap}
1690 is a list of keymaps, only those keymaps are searched.
1692 Usually it's best to use @code{overriding-local-map} as the expression
1693 for @var{keymap}. Then @code{where-is-internal} searches precisely the
1694 keymaps that are active. To search only the global map, pass
1695 @code{(keymap)} (an empty keymap) as @var{keymap}.
1697 If @var{firstonly} is @code{non-ascii}, then the value is a single
1698 vector representing the first key sequence found, rather than a list of
1699 all possible key sequences. If @var{firstonly} is @code{t}, then the
1700 value is the first key sequence, except that key sequences consisting
1701 entirely of @acronym{ASCII} characters (or meta variants of @acronym{ASCII}
1702 characters) are preferred to all other key sequences and that the
1703 return value can never be a menu binding.
1705 If @var{noindirect} is non-@code{nil}, @code{where-is-internal} doesn't
1706 follow indirect keymap bindings. This makes it possible to search for
1707 an indirect definition itself.
1709 When command remapping is in effect (@pxref{Remapping Commands}),
1710 @code{where-is-internal} figures out when a command will be run due to
1711 remapping and reports keys accordingly. It also returns @code{nil} if
1712 @var{command} won't really be run because it has been remapped to some
1713 other command. However, if @var{no-remap} is non-@code{nil}.
1714 @code{where-is-internal} ignores remappings.
1718 (where-is-internal 'describe-function)
1719 @result{} ("\^hf" "\^hd")
1724 @deffn Command describe-bindings &optional prefix buffer-or-name
1725 This function creates a listing of all current key bindings, and
1726 displays it in a buffer named @samp{*Help*}. The text is grouped by
1727 modes---minor modes first, then the major mode, then global bindings.
1729 If @var{prefix} is non-@code{nil}, it should be a prefix key; then the
1730 listing includes only keys that start with @var{prefix}.
1732 The listing describes meta characters as @key{ESC} followed by the
1733 corresponding non-meta character.
1735 When several characters with consecutive @acronym{ASCII} codes have the
1736 same definition, they are shown together, as
1737 @samp{@var{firstchar}..@var{lastchar}}. In this instance, you need to
1738 know the @acronym{ASCII} codes to understand which characters this means.
1739 For example, in the default global map, the characters @samp{@key{SPC}
1740 ..@: ~} are described by a single line. @key{SPC} is @acronym{ASCII} 32,
1741 @kbd{~} is @acronym{ASCII} 126, and the characters between them include all
1742 the normal printing characters, (e.g., letters, digits, punctuation,
1743 etc.@:); all these characters are bound to @code{self-insert-command}.
1745 If @var{buffer-or-name} is non-@code{nil}, it should be a buffer or a
1746 buffer name. Then @code{describe-bindings} lists that buffer's bindings,
1747 instead of the current buffer's.
1751 @section Menu Keymaps
1752 @cindex menu keymaps
1755 A keymap can define a menu as well as bindings for keyboard keys and
1756 mouse button. Menus are usually actuated with the mouse, but they can
1757 work with the keyboard also.
1760 * Defining Menus:: How to make a keymap that defines a menu.
1761 * Mouse Menus:: How users actuate the menu with the mouse.
1762 * Keyboard Menus:: How they actuate it with the keyboard.
1763 * Menu Example:: Making a simple menu.
1764 * Menu Bar:: How to customize the menu bar.
1765 * Tool Bar:: A tool bar is a row of images.
1766 * Modifying Menus:: How to add new items to a menu.
1769 @node Defining Menus
1770 @subsection Defining Menus
1771 @cindex defining menus
1772 @cindex menu prompt string
1773 @cindex prompt string (of menu)
1775 A keymap is suitable for menu use if it has an @dfn{overall prompt
1776 string}, which is a string that appears as an element of the keymap.
1777 (@xref{Format of Keymaps}.) The string should describe the purpose of
1778 the menu's commands. Emacs displays the overall prompt string as the
1779 menu title in some cases, depending on the toolkit (if any) used for
1780 displaying menus.@footnote{It is required for menus which do not use a
1781 toolkit, e.g.@: under MS-DOS.} Keyboard menus also display the overall
1784 The easiest way to construct a keymap with a prompt string is to specify
1785 the string as an argument when you call @code{make-keymap},
1786 @code{make-sparse-keymap} (@pxref{Creating Keymaps}), or
1787 @code{define-prefix-command} (@pxref{Definition of define-prefix-command}).
1790 @defun keymap-prompt keymap
1791 This function returns the overall prompt string of @var{keymap},
1792 or @code{nil} if it has none.
1795 The order of items in the menu is the same as the order of bindings in
1796 the keymap. Since @code{define-key} puts new bindings at the front, you
1797 should define the menu items starting at the bottom of the menu and
1798 moving to the top, if you care about the order. When you add an item to
1799 an existing menu, you can specify its position in the menu using
1800 @code{define-key-after} (@pxref{Modifying Menus}).
1803 * Simple Menu Items:: A simple kind of menu key binding,
1804 limited in capabilities.
1805 * Extended Menu Items:: More powerful menu item definitions
1806 let you specify keywords to enable
1808 * Menu Separators:: Drawing a horizontal line through a menu.
1809 * Alias Menu Items:: Using command aliases in menu items.
1812 @node Simple Menu Items
1813 @subsubsection Simple Menu Items
1815 The simpler and older way to define a menu keymap binding
1819 (@var{item-string} . @var{real-binding})
1823 The @sc{car}, @var{item-string}, is the string to be displayed in the
1824 menu. It should be short---preferably one to three words. It should
1825 describe the action of the command it corresponds to. Note that it is
1826 not generally possible to display non-@acronym{ASCII} text in menus. It will
1827 work for keyboard menus and will work to a large extent when Emacs is
1828 built with the Gtk+ toolkit.@footnote{In this case, the text is first
1829 encoded using the @code{utf-8} coding system and then rendered by the
1830 toolkit as it sees fit.}
1832 You can also supply a second string, called the help string, as follows:
1835 (@var{item-string} @var{help} . @var{real-binding})
1838 @var{help} specifies a ``help-echo'' string to display while the mouse
1839 is on that item in the same way as @code{help-echo} text properties
1840 (@pxref{Help display}).
1842 As far as @code{define-key} is concerned, @var{item-string} and
1843 @var{help-string} are part of the event's binding. However,
1844 @code{lookup-key} returns just @var{real-binding}, and only
1845 @var{real-binding} is used for executing the key.
1847 If @var{real-binding} is @code{nil}, then @var{item-string} appears in
1848 the menu but cannot be selected.
1850 If @var{real-binding} is a symbol and has a non-@code{nil}
1851 @code{menu-enable} property, that property is an expression that
1852 controls whether the menu item is enabled. Every time the keymap is
1853 used to display a menu, Emacs evaluates the expression, and it enables
1854 the menu item only if the expression's value is non-@code{nil}. When a
1855 menu item is disabled, it is displayed in a ``fuzzy'' fashion, and
1858 The menu bar does not recalculate which items are enabled every time you
1859 look at a menu. This is because the X toolkit requires the whole tree
1860 of menus in advance. To force recalculation of the menu bar, call
1861 @code{force-mode-line-update} (@pxref{Mode Line Format}).
1863 You've probably noticed that menu items show the equivalent keyboard key
1864 sequence (if any) to invoke the same command. To save time on
1865 recalculation, menu display caches this information in a sublist in the
1868 @c This line is not too long--rms.
1870 (@var{item-string} @r{[}@var{help-string}@r{]} (@var{key-binding-data}) . @var{real-binding})
1874 Don't put these sublists in the menu item yourself; menu display
1875 calculates them automatically. Don't mention keyboard equivalents in
1876 the item strings themselves, since that is redundant.
1878 @node Extended Menu Items
1879 @subsubsection Extended Menu Items
1882 An extended-format menu item is a more flexible and also cleaner
1883 alternative to the simple format. It consists of a list that starts
1884 with the symbol @code{menu-item}. To define a non-selectable string,
1885 the item looks like this:
1888 (menu-item @var{item-name})
1892 A string starting with two or more dashes specifies a separator line;
1893 see @ref{Menu Separators}.
1895 To define a real menu item which can be selected, the extended format
1896 item looks like this:
1899 (menu-item @var{item-name} @var{real-binding}
1900 . @var{item-property-list})
1904 Here, @var{item-name} is an expression which evaluates to the menu item
1905 string. Thus, the string need not be a constant. The third element,
1906 @var{real-binding}, is the command to execute. The tail of the list,
1907 @var{item-property-list}, has the form of a property list which contains
1908 other information. Here is a table of the properties that are supported:
1911 @item :enable @var{form}
1912 The result of evaluating @var{form} determines whether the item is
1913 enabled (non-@code{nil} means yes). If the item is not enabled,
1914 you can't really click on it.
1916 @item :visible @var{form}
1917 The result of evaluating @var{form} determines whether the item should
1918 actually appear in the menu (non-@code{nil} means yes). If the item
1919 does not appear, then the menu is displayed as if this item were
1922 @item :help @var{help}
1923 The value of this property, @var{help}, specifies a ``help-echo'' string
1924 to display while the mouse is on that item. This is displayed in the
1925 same way as @code{help-echo} text properties (@pxref{Help display}).
1926 Note that this must be a constant string, unlike the @code{help-echo}
1927 property for text and overlays.
1929 @item :button (@var{type} . @var{selected})
1930 This property provides a way to define radio buttons and toggle buttons.
1931 The @sc{car}, @var{type}, says which: it should be @code{:toggle} or
1932 @code{:radio}. The @sc{cdr}, @var{selected}, should be a form; the
1933 result of evaluating it says whether this button is currently selected.
1935 A @dfn{toggle} is a menu item which is labeled as either ``on'' or ``off''
1936 according to the value of @var{selected}. The command itself should
1937 toggle @var{selected}, setting it to @code{t} if it is @code{nil},
1938 and to @code{nil} if it is @code{t}. Here is how the menu item
1939 to toggle the @code{debug-on-error} flag is defined:
1942 (menu-item "Debug on Error" toggle-debug-on-error
1944 . (and (boundp 'debug-on-error)
1949 This works because @code{toggle-debug-on-error} is defined as a command
1950 which toggles the variable @code{debug-on-error}.
1952 @dfn{Radio buttons} are a group of menu items, in which at any time one
1953 and only one is ``selected.'' There should be a variable whose value
1954 says which one is selected at any time. The @var{selected} form for
1955 each radio button in the group should check whether the variable has the
1956 right value for selecting that button. Clicking on the button should
1957 set the variable so that the button you clicked on becomes selected.
1959 @item :key-sequence @var{key-sequence}
1960 This property specifies which key sequence is likely to be bound to the
1961 same command invoked by this menu item. If you specify the right key
1962 sequence, that makes preparing the menu for display run much faster.
1964 If you specify the wrong key sequence, it has no effect; before Emacs
1965 displays @var{key-sequence} in the menu, it verifies that
1966 @var{key-sequence} is really equivalent to this menu item.
1968 @item :key-sequence nil
1969 This property indicates that there is normally no key binding which is
1970 equivalent to this menu item. Using this property saves time in
1971 preparing the menu for display, because Emacs does not need to search
1972 the keymaps for a keyboard equivalent for this menu item.
1974 However, if the user has rebound this item's definition to a key
1975 sequence, Emacs ignores the @code{:keys} property and finds the keyboard
1978 @item :keys @var{string}
1979 This property specifies that @var{string} is the string to display
1980 as the keyboard equivalent for this menu item. You can use
1981 the @samp{\\[...]} documentation construct in @var{string}.
1983 @item :filter @var{filter-fn}
1984 This property provides a way to compute the menu item dynamically.
1985 The property value @var{filter-fn} should be a function of one argument;
1986 when it is called, its argument will be @var{real-binding}. The
1987 function should return the binding to use instead.
1989 Emacs can call this function at any time that it does redisplay or
1990 operates on menu data structures, so you should write it so it can
1991 safely be called at any time.
1994 @node Menu Separators
1995 @subsubsection Menu Separators
1996 @cindex menu separators
1998 A menu separator is a kind of menu item that doesn't display any
1999 text---instead, it divides the menu into subparts with a horizontal line.
2000 A separator looks like this in the menu keymap:
2003 (menu-item @var{separator-type})
2007 where @var{separator-type} is a string starting with two or more dashes.
2009 In the simplest case, @var{separator-type} consists of only dashes.
2010 That specifies the default kind of separator. (For compatibility,
2011 @code{""} and @code{-} also count as separators.)
2013 Certain other values of @var{separator-type} specify a different
2014 style of separator. Here is a table of them:
2019 An extra vertical space, with no actual line.
2021 @item "--single-line"
2022 A single line in the menu's foreground color.
2024 @item "--double-line"
2025 A double line in the menu's foreground color.
2027 @item "--single-dashed-line"
2028 A single dashed line in the menu's foreground color.
2030 @item "--double-dashed-line"
2031 A double dashed line in the menu's foreground color.
2033 @item "--shadow-etched-in"
2034 A single line with a 3D sunken appearance. This is the default,
2035 used separators consisting of dashes only.
2037 @item "--shadow-etched-out"
2038 A single line with a 3D raised appearance.
2040 @item "--shadow-etched-in-dash"
2041 A single dashed line with a 3D sunken appearance.
2043 @item "--shadow-etched-out-dash"
2044 A single dashed line with a 3D raised appearance.
2046 @item "--shadow-double-etched-in"
2047 Two lines with a 3D sunken appearance.
2049 @item "--shadow-double-etched-out"
2050 Two lines with a 3D raised appearance.
2052 @item "--shadow-double-etched-in-dash"
2053 Two dashed lines with a 3D sunken appearance.
2055 @item "--shadow-double-etched-out-dash"
2056 Two dashed lines with a 3D raised appearance.
2059 You can also give these names in another style, adding a colon after
2060 the double-dash and replacing each single dash with capitalization of
2061 the following word. Thus, @code{"--:singleLine"}, is equivalent to
2062 @code{"--single-line"}.
2064 Some systems and display toolkits don't really handle all of these
2065 separator types. If you use a type that isn't supported, the menu
2066 displays a similar kind of separator that is supported.
2068 @node Alias Menu Items
2069 @subsubsection Alias Menu Items
2071 Sometimes it is useful to make menu items that use the ``same''
2072 command but with different enable conditions. The best way to do this
2073 in Emacs now is with extended menu items; before that feature existed,
2074 it could be done by defining alias commands and using them in menu
2075 items. Here's an example that makes two aliases for
2076 @code{toggle-read-only} and gives them different enable conditions:
2079 (defalias 'make-read-only 'toggle-read-only)
2080 (put 'make-read-only 'menu-enable '(not buffer-read-only))
2081 (defalias 'make-writable 'toggle-read-only)
2082 (put 'make-writable 'menu-enable 'buffer-read-only)
2085 When using aliases in menus, often it is useful to display the
2086 equivalent key bindings for the ``real'' command name, not the aliases
2087 (which typically don't have any key bindings except for the menu
2088 itself). To request this, give the alias symbol a non-@code{nil}
2089 @code{menu-alias} property. Thus,
2092 (put 'make-read-only 'menu-alias t)
2093 (put 'make-writable 'menu-alias t)
2097 causes menu items for @code{make-read-only} and @code{make-writable} to
2098 show the keyboard bindings for @code{toggle-read-only}.
2101 @subsection Menus and the Mouse
2103 The usual way to make a menu keymap produce a menu is to make it the
2104 definition of a prefix key. (A Lisp program can explicitly pop up a
2105 menu and receive the user's choice---see @ref{Pop-Up Menus}.)
2107 If the prefix key ends with a mouse event, Emacs handles the menu keymap
2108 by popping up a visible menu, so that the user can select a choice with
2109 the mouse. When the user clicks on a menu item, the event generated is
2110 whatever character or symbol has the binding that brought about that
2111 menu item. (A menu item may generate a series of events if the menu has
2112 multiple levels or comes from the menu bar.)
2114 It's often best to use a button-down event to trigger the menu. Then
2115 the user can select a menu item by releasing the button.
2117 A single keymap can appear as multiple menu panes, if you explicitly
2118 arrange for this. The way to do this is to make a keymap for each pane,
2119 then create a binding for each of those maps in the main keymap of the
2120 menu. Give each of these bindings an item string that starts with
2121 @samp{@@}. The rest of the item string becomes the name of the pane.
2122 See the file @file{lisp/mouse.el} for an example of this. Any ordinary
2123 bindings with @samp{@@}-less item strings are grouped into one pane,
2124 which appears along with the other panes explicitly created for the
2127 X toolkit menus don't have panes; instead, they can have submenus.
2128 Every nested keymap becomes a submenu, whether the item string starts
2129 with @samp{@@} or not. In a toolkit version of Emacs, the only thing
2130 special about @samp{@@} at the beginning of an item string is that the
2131 @samp{@@} doesn't appear in the menu item.
2133 Multiple keymaps that define the same menu prefix key produce
2134 separate panes or separate submenus.
2136 @node Keyboard Menus
2137 @subsection Menus and the Keyboard
2139 When a prefix key ending with a keyboard event (a character or function
2140 key) has a definition that is a menu keymap, the user can use the
2141 keyboard to choose a menu item.
2143 Emacs displays the menu's overall prompt string followed by the
2144 alternatives (the item strings of the bindings) in the echo area. If
2145 the bindings don't all fit at once, the user can type @key{SPC} to see
2146 the next line of alternatives. Successive uses of @key{SPC} eventually
2147 get to the end of the menu and then cycle around to the beginning. (The
2148 variable @code{menu-prompt-more-char} specifies which character is used
2149 for this; @key{SPC} is the default.)
2151 When the user has found the desired alternative from the menu, he or she
2152 should type the corresponding character---the one whose binding is that
2156 In a menu intended for keyboard use, each menu item must clearly
2157 indicate what character to type. The best convention to use is to make
2158 the character the first letter of the item string---that is something
2159 users will understand without being told. We plan to change this; by
2160 the time you read this manual, keyboard menus may explicitly name the
2161 key for each alternative.
2164 This way of using menus in an Emacs-like editor was inspired by the
2167 @defvar menu-prompt-more-char
2168 This variable specifies the character to use to ask to see
2169 the next line of a menu. Its initial value is 32, the code
2174 @subsection Menu Example
2175 @cindex menu definition example
2177 Here is a complete example of defining a menu keymap. It is the
2178 definition of the @samp{Replace} submenu in the @samp{Edit} menu in
2179 the menu bar, and it uses the extended menu item format
2180 (@pxref{Extended Menu Items}). First we create the keymap, and give
2184 (defvar menu-bar-replace-menu (make-sparse-keymap "Replace"))
2188 Next we define the menu items:
2191 (define-key menu-bar-replace-menu [tags-repl-continue]
2192 '(menu-item "Continue Replace" tags-loop-continue
2193 :help "Continue last tags replace operation"))
2194 (define-key menu-bar-replace-menu [tags-repl]
2195 '(menu-item "Replace in tagged files" tags-query-replace
2196 :help "Interactively replace a regexp in all tagged files"))
2197 (define-key menu-bar-replace-menu [separator-replace-tags]
2203 Note the symbols which the bindings are ``made for''; these appear
2204 inside square brackets, in the key sequence being defined. In some
2205 cases, this symbol is the same as the command name; sometimes it is
2206 different. These symbols are treated as ``function keys'', but they are
2207 not real function keys on the keyboard. They do not affect the
2208 functioning of the menu itself, but they are ``echoed'' in the echo area
2209 when the user selects from the menu, and they appear in the output of
2210 @code{where-is} and @code{apropos}.
2212 The menu in this example is intended for use with the mouse. If a
2213 menu is intended for use with the keyboard, that is, if it is bound to
2214 a key sequence ending with a keyboard event, then the menu items
2215 should be bound to characters or ``real'' function keys, that can be
2216 typed with the keyboard.
2218 The binding whose definition is @code{("--")} is a separator line.
2219 Like a real menu item, the separator has a key symbol, in this case
2220 @code{separator-replace-tags}. If one menu has two separators, they
2221 must have two different key symbols.
2223 Here is how we make this menu appear as an item in the parent menu:
2226 (define-key menu-bar-edit-menu [replace]
2227 (list 'menu-item "Replace" menu-bar-replace-menu))
2231 Note that this incorporates the submenu keymap, which is the value of
2232 the variable @code{menu-bar-replace-menu}, rather than the symbol
2233 @code{menu-bar-replace-menu} itself. Using that symbol in the parent
2234 menu item would be meaningless because @code{menu-bar-replace-menu} is
2237 If you wanted to attach the same replace menu to a mouse click, you
2241 (define-key global-map [C-S-down-mouse-1]
2242 menu-bar-replace-menu)
2246 @subsection The Menu Bar
2249 Most window systems allow each frame to have a @dfn{menu bar}---a
2250 permanently displayed menu stretching horizontally across the top of the
2251 frame. The items of the menu bar are the subcommands of the fake
2252 ``function key'' @code{menu-bar}, as defined in the active keymaps.
2254 To add an item to the menu bar, invent a fake ``function key'' of your
2255 own (let's call it @var{key}), and make a binding for the key sequence
2256 @code{[menu-bar @var{key}]}. Most often, the binding is a menu keymap,
2257 so that pressing a button on the menu bar item leads to another menu.
2259 When more than one active keymap defines the same fake function key
2260 for the menu bar, the item appears just once. If the user clicks on
2261 that menu bar item, it brings up a single, combined menu containing
2262 all the subcommands of that item---the global subcommands, the local
2263 subcommands, and the minor mode subcommands.
2265 The variable @code{overriding-local-map} is normally ignored when
2266 determining the menu bar contents. That is, the menu bar is computed
2267 from the keymaps that would be active if @code{overriding-local-map}
2268 were @code{nil}. @xref{Active Keymaps}.
2270 In order for a frame to display a menu bar, its @code{menu-bar-lines}
2271 parameter must be greater than zero. Emacs uses just one line for the
2272 menu bar itself; if you specify more than one line, the other lines
2273 serve to separate the menu bar from the windows in the frame. We
2274 recommend 1 or 2 as the value of @code{menu-bar-lines}. @xref{Layout
2277 Here's an example of setting up a menu bar item:
2281 (modify-frame-parameters (selected-frame)
2282 '((menu-bar-lines . 2)))
2286 ;; @r{Make a menu keymap (with a prompt string)}
2287 ;; @r{and make it the menu bar item's definition.}
2288 (define-key global-map [menu-bar words]
2289 (cons "Words" (make-sparse-keymap "Words")))
2293 ;; @r{Define specific subcommands in this menu.}
2294 (define-key global-map
2295 [menu-bar words forward]
2296 '("Forward word" . forward-word))
2299 (define-key global-map
2300 [menu-bar words backward]
2301 '("Backward word" . backward-word))
2305 A local keymap can cancel a menu bar item made by the global keymap by
2306 rebinding the same fake function key with @code{undefined} as the
2307 binding. For example, this is how Dired suppresses the @samp{Edit} menu
2311 (define-key dired-mode-map [menu-bar edit] 'undefined)
2315 @code{edit} is the fake function key used by the global map for the
2316 @samp{Edit} menu bar item. The main reason to suppress a global
2317 menu bar item is to regain space for mode-specific items.
2319 @defvar menu-bar-final-items
2320 Normally the menu bar shows global items followed by items defined by the
2323 This variable holds a list of fake function keys for items to display at
2324 the end of the menu bar rather than in normal sequence. The default
2325 value is @code{(help-menu)}; thus, the @samp{Help} menu item normally appears
2326 at the end of the menu bar, following local menu items.
2329 @defvar menu-bar-update-hook
2330 This normal hook is run by redisplay to update the menu bar contents,
2331 before redisplaying the menu bar. You can use it to update submenus
2332 whose contents should vary. Since this hook is run frequently, we
2333 advise you to ensure that the functions it calls do not take much time
2338 @subsection Tool bars
2341 A @dfn{tool bar} is a row of icons at the top of a frame, that execute
2342 commands when you click on them---in effect, a kind of graphical menu
2345 The frame parameter @code{tool-bar-lines} (X resource @samp{toolBar})
2346 controls how many lines' worth of height to reserve for the tool bar. A
2347 zero value suppresses the tool bar. If the value is nonzero, and
2348 @code{auto-resize-tool-bars} is non-@code{nil}, the tool bar expands and
2349 contracts automatically as needed to hold the specified contents.
2351 The tool bar contents are controlled by a menu keymap attached to a
2352 fake ``function key'' called @code{tool-bar} (much like the way the menu
2353 bar is controlled). So you define a tool bar item using
2354 @code{define-key}, like this:
2357 (define-key global-map [tool-bar @var{key}] @var{item})
2361 where @var{key} is a fake ``function key'' to distinguish this item from
2362 other items, and @var{item} is a menu item key binding (@pxref{Extended
2363 Menu Items}), which says how to display this item and how it behaves.
2365 The usual menu keymap item properties, @code{:visible},
2366 @code{:enable}, @code{:button}, and @code{:filter}, are useful in
2367 tool bar bindings and have their normal meanings. The @var{real-binding}
2368 in the item must be a command, not a keymap; in other words, it does not
2369 work to define a tool bar icon as a prefix key.
2371 The @code{:help} property specifies a ``help-echo'' string to display
2372 while the mouse is on that item. This is displayed in the same way as
2373 @code{help-echo} text properties (@pxref{Help display}).
2375 In addition, you should use the @code{:image} property;
2376 this is how you specify the image to display in the tool bar:
2379 @item :image @var{image}
2380 @var{images} is either a single image specification or a vector of four
2381 image specifications. If you use a vector of four,
2382 one of them is used, depending on circumstances:
2386 Used when the item is enabled and selected.
2388 Used when the item is enabled and deselected.
2390 Used when the item is disabled and selected.
2392 Used when the item is disabled and deselected.
2396 If @var{image} is a single image specification, Emacs draws the tool bar
2397 button in disabled state by applying an edge-detection algorithm to the
2400 The default tool bar is defined so that items specific to editing do not
2401 appear for major modes whose command symbol has a @code{mode-class}
2402 property of @code{special} (@pxref{Major Mode Conventions}). Major
2403 modes may add items to the global bar by binding @code{[tool-bar
2404 @var{foo}]} in their local map. It makes sense for some major modes to
2405 replace the default tool bar items completely, since not many can be
2406 accommodated conveniently, and the default bindings make this easy by
2407 using an indirection through @code{tool-bar-map}.
2409 @defvar tool-bar-map
2410 @tindex tool-bar-map
2411 By default, the global map binds @code{[tool-bar]} as follows:
2413 (global-set-key [tool-bar]
2414 '(menu-item "tool bar" ignore
2415 :filter (lambda (ignore) tool-bar-map)))
2418 Thus the tool bar map is derived dynamically from the value of variable
2419 @code{tool-bar-map} and you should normally adjust the default (global)
2420 tool bar by changing that map. Major modes may replace the global bar
2421 completely by making @code{tool-bar-map} buffer-local and set to a
2422 keymap containing only the desired items. Info mode provides an
2426 There are two convenience functions for defining tool bar items, as
2429 @defun tool-bar-add-item icon def key &rest props
2430 @tindex tool-bar-add-item
2431 This function adds an item to the tool bar by modifying
2432 @code{tool-bar-map}. The image to use is defined by @var{icon}, which
2433 is the base name of an XPM, XBM or PBM image file to be located by
2434 @code{find-image}. Given a value @samp{"exit"}, say, @file{exit.xpm},
2435 @file{exit.pbm} and @file{exit.xbm} would be searched for in that order
2436 on a color display. On a monochrome display, the search order is
2437 @samp{.pbm}, @samp{.xbm} and @samp{.xpm}. The binding to use is the
2438 command @var{def}, and @var{key} is the fake function key symbol in the
2439 prefix keymap. The remaining arguments @var{props} are additional
2440 property list elements to add to the menu item specification.
2442 To define items in some local map, bind @code{tool-bar-map} with
2443 @code{let} around calls of this function:
2445 (defvar foo-tool-bar-map
2446 (let ((tool-bar-map (make-sparse-keymap)))
2447 (tool-bar-add-item @dots{})
2453 @defun tool-bar-add-item-from-menu command icon &optional map &rest props
2454 @tindex tool-bar-add-item-from-menu
2455 This function is a convenience for defining tool bar items which are
2456 consistent with existing menu bar bindings. The binding of
2457 @var{command} is looked up in the menu bar in @var{map} (default
2458 @code{global-map}) and modified to add an image specification for
2459 @var{icon}, which is found in the same way as by
2460 @code{tool-bar-add-item}. The resulting binding is then placed in
2461 @code{tool-bar-map}, so use this function only for global tool bar
2464 @var{map} must contain an appropriate keymap bound to
2465 @code{[menu-bar]}. The remaining arguments @var{props} are additional
2466 property list elements to add to the menu item specification.
2469 @defun tool-bar-local-item-from-menu command icon in-map &optional from-map &rest props
2470 This function is used for making non-global tool bar items. Use it
2471 like @code{tool-bar-add-item-from-menu} except that @var{in-map}
2472 specifies the local map to make the definition in. The argument
2473 @var{from-map} is like the @var{map} argument of
2474 @code{tool-bar-add-item-from-menu}.
2477 @tindex auto-resize-tool-bar
2478 @defvar auto-resize-tool-bar
2479 If this variable is non-@code{nil}, the tool bar automatically resizes to
2480 show all defined tool bar items---but not larger than a quarter of the
2484 @tindex auto-raise-tool-bar-buttons
2485 @defvar auto-raise-tool-bar-buttons
2486 If this variable is non-@code{nil}, tool bar items display
2487 in raised form when the mouse moves over them.
2490 @tindex tool-bar-button-margin
2491 @defvar tool-bar-button-margin
2492 This variable specifies an extra margin to add around tool bar items.
2493 The value is an integer, a number of pixels. The default is 4.
2496 @tindex tool-bar-button-relief
2497 @defvar tool-bar-button-relief
2498 This variable specifies the shadow width for tool bar items.
2499 The value is an integer, a number of pixels. The default is 1.
2502 @tindex tool-bar-border
2503 @defvar tool-bar-border
2504 This variable specifies the height of the border drawn below the tool
2505 bar area. An integer value specifies height as a number of pixels.
2506 If the value is one of @code{internal-border-width} (the default) or
2507 @code{border-width}, the tool bar border height corresponds to the
2508 corresponding frame parameter.
2511 You can define a special meaning for clicking on a tool bar item with
2512 the shift, control, meta, etc., modifiers. You do this by setting up
2513 additional items that relate to the original item through the fake
2514 function keys. Specifically, the additional items should use the
2515 modified versions of the same fake function key used to name the
2518 Thus, if the original item was defined this way,
2521 (define-key global-map [tool-bar shell]
2522 '(menu-item "Shell" shell
2523 :image (image :type xpm :file "shell.xpm")))
2527 then here is how you can define clicking on the same tool bar image with
2531 (define-key global-map [tool-bar S-shell] 'some-command)
2534 @xref{Function Keys}, for more information about how to add modifiers to
2537 @node Modifying Menus
2538 @subsection Modifying Menus
2540 When you insert a new item in an existing menu, you probably want to
2541 put it in a particular place among the menu's existing items. If you
2542 use @code{define-key} to add the item, it normally goes at the front of
2543 the menu. To put it elsewhere in the menu, use @code{define-key-after}:
2545 @defun define-key-after map key binding &optional after
2546 Define a binding in @var{map} for @var{key}, with value @var{binding},
2547 just like @code{define-key}, but position the binding in @var{map} after
2548 the binding for the event @var{after}. The argument @var{key} should be
2549 of length one---a vector or string with just one element. But
2550 @var{after} should be a single event type---a symbol or a character, not
2551 a sequence. The new binding goes after the binding for @var{after}. If
2552 @var{after} is @code{t} or is omitted, then the new binding goes last, at
2553 the end of the keymap. However, new bindings are added before any
2559 (define-key-after my-menu [drink]
2560 '("Drink" . drink-command) 'eat)
2564 makes a binding for the fake function key @key{DRINK} and puts it
2565 right after the binding for @key{EAT}.
2567 Here is how to insert an item called @samp{Work} in the @samp{Signals}
2568 menu of Shell mode, after the item @code{break}:
2572 (lookup-key shell-mode-map [menu-bar signals])
2573 [work] '("Work" . work-command) 'break)
2578 arch-tag: cfb87287-9364-4e46-9e93-6c2f7f6ae794