GNU Info
(elisp)Functions for Key Lookup
Functions for Key Lookup
========================
Here are the functions and variables pertaining to key lookup.
- Function: lookup-key keymap key &optional accept-defaults
This function returns the definition of KEY in KEYMAP. All the
other functions described in this chapter that look up keys use
`lookup-key'. Here are examples:
(lookup-key (current-global-map) "\C-x\C-f")
=> find-file
(lookup-key (current-global-map) "\C-x\C-f12345")
=> 2
If the string or vector KEY is not a valid key sequence according
to the prefix keys specified in KEYMAP, it must be "too long" and
have extra events at the end that do not fit into a single key
sequence. Then the value is a number, the number of events at the
front of KEY that compose a complete key.
If ACCEPT-DEFAULTS is non-`nil', then `lookup-key' considers
default bindings as well as bindings for the specific events in
KEY. Otherwise, `lookup-key' reports only bindings for the
specific sequence KEY, ignoring default bindings except when you
explicitly ask about them. (To do this, supply `t' as an element
of KEY; see Note: Format of Keymaps.)
If KEY contains a meta character (not a function key), that
character is implicitly replaced by a two-character sequence: the
value of `meta-prefix-char', followed by the corresponding non-meta
character. Thus, the first example below is handled by conversion
into the second example.
(lookup-key (current-global-map) "\M-f")
=> forward-word
(lookup-key (current-global-map) "\ef")
=> forward-word
Unlike `read-key-sequence', this function does not modify the
specified events in ways that discard information (Note: Key
Sequence Input). In particular, it does not convert letters to
lower case and it does not change drag events to clicks.
- Command: undefined
Used in keymaps to undefine keys. It calls `ding', but does not
cause an error.
- Function: key-binding key &optional accept-defaults
This function returns the binding for KEY in the current keymaps,
trying all the active keymaps. The result is `nil' if KEY is
undefined in the keymaps.
The argument ACCEPT-DEFAULTS controls checking for default
bindings, as in `lookup-key' (above).
An error is signaled if KEY is not a string or a vector.
(key-binding "\C-x\C-f")
=> find-file
- Function: local-key-binding key &optional accept-defaults
This function returns the binding for KEY in the current local
keymap, or `nil' if it is undefined there.
The argument ACCEPT-DEFAULTS controls checking for default
bindings, as in `lookup-key' (above).
- Function: global-key-binding key &optional accept-defaults
This function returns the binding for command KEY in the current
global keymap, or `nil' if it is undefined there.
The argument ACCEPT-DEFAULTS controls checking for default
bindings, as in `lookup-key' (above).
- Function: minor-mode-key-binding key &optional accept-defaults
This function returns a list of all the active minor mode bindings
of KEY. More precisely, it returns an alist of pairs `(MODENAME .
BINDING)', where MODENAME is the variable that enables the minor
mode, and BINDING is KEY's binding in that mode. If KEY has no
minor-mode bindings, the value is `nil'.
If the first binding found is not a prefix definition (a keymap or
a symbol defined as a keymap), all subsequent bindings from other
minor modes are omitted, since they would be completely shadowed.
Similarly, the list omits non-prefix bindings that follow prefix
bindings.
The argument ACCEPT-DEFAULTS controls checking for default
bindings, as in `lookup-key' (above).
- Variable: meta-prefix-char
This variable is the meta-prefix character code. It is used when
translating a meta character to a two-character sequence so it can
be looked up in a keymap. For useful results, the value should be
a prefix event (Note: Prefix Keys). The default value is 27,
which is the ASCII code for <ESC>.
As long as the value of `meta-prefix-char' remains 27, key lookup
translates `M-b' into `<ESC> b', which is normally defined as the
`backward-word' command. However, if you were to set
`meta-prefix-char' to 24, the code for `C-x', then Emacs will
translate `M-b' into `C-x b', whose standard binding is the
`switch-to-buffer' command. (Don't actually do this!) Here is an
illustration of what would happen:
meta-prefix-char ; The default value.
=> 27
(key-binding "\M-b")
=> backward-word
?\C-x ; The print representation
=> 24 ; of a character.
(setq meta-prefix-char 24)
=> 24
(key-binding "\M-b")
=> switch-to-buffer ; Now, typing `M-b' is
; like typing `C-x b'.
(setq meta-prefix-char 27) ; Avoid confusion!
=> 27 ; Restore the default value!
This translation of one event into two happens only for
characters, not for other kinds of input events. Thus, `M-<F1>',
a function key, is not converted into `<ESC> <F1>'.
automatically generated by info2www version 1.2.2.9