@section Customizing Key Bindings
@cindex key bindings
- This section describes @dfn{key bindings}, which map keys to commands,
-and @dfn{keymaps}, which record key bindings. It also explains how
-to customize key bindings.
-
- Recall that a command is a Lisp function whose definition provides for
-interactive use. Like every Lisp function, a command has a function
-name, which usually consists of lower-case letters and hyphens.
+ This section describes @dfn{key bindings}, which map keys to
+commands, and @dfn{keymaps}, which record key bindings. It also
+explains how to customize key bindings, which is done by editing your
+init file (@pxref{Init Rebinding}).
@menu
* Keymaps:: Generalities. The global keymap.
@subsection Keymaps
@cindex keymap
- The bindings between key sequences and command functions are recorded
-in data structures called @dfn{keymaps}. Emacs has many of these, each
-used on particular occasions.
+ As described in @ref{Commands}, each Emacs command is a Lisp
+function whose definition provides for interactive use. Like every
+Lisp function, a command has a function name, which usually consists
+of lower-case letters and hyphens.
A @dfn{key sequence} (@dfn{key}, for short) is a sequence of
@dfn{input events} that have a meaning as a unit. Input events
include characters, function keys and mouse buttons---all the inputs
-that you can send to the computer with your terminal. A key sequence
-gets its meaning from its @dfn{binding}, which says what command it
-runs. The role of keymaps is to record these bindings.
+that you can send to the computer. A key sequence gets its meaning
+from its @dfn{binding}, which says what command it runs.
+
+ The bindings between key sequences and command functions are
+recorded in data structures called @dfn{keymaps}. Emacs has many of
+these, each used on particular occasions.
@cindex global keymap
The @dfn{global} keymap is the most important keymap because it is
-always in effect. The global keymap defines keys for Fundamental mode;
-most of these definitions are common to most or all major modes. Each
-major or minor mode can have its own keymap which overrides the global
-definitions of some keys.
+always in effect. The global keymap defines keys for Fundamental mode
+(@pxref{Major Modes}); most of these definitions are common to most or
+all major modes. Each major or minor mode can have its own keymap
+which overrides the global definitions of some keys.
For example, a self-inserting character such as @kbd{g} is
self-inserting because the global keymap binds it to the command
-@code{self-insert-command}. The standard Emacs editing characters such
-as @kbd{C-a} also get their standard meanings from the global keymap.
-Commands to rebind keys, such as @kbd{M-x global-set-key}, actually work
-by storing the new binding in the proper place in the global map.
-@xref{Rebinding}.
+@code{self-insert-command}. The standard Emacs editing characters
+such as @kbd{C-a} also get their standard meanings from the global
+keymap. Commands to rebind keys, such as @kbd{M-x global-set-key},
+work by storing the new binding in the proper place in the global map
+(@pxref{Rebinding}).
@cindex function key
Most modern keyboards have function keys as well as character keys.
Function keys send input events just as character keys do, and keymaps
-can have bindings for them. On text terminals, typing a function key
-actually sends the computer a sequence of characters; the precise
-details of the sequence depends on which function key and on the model
-of terminal you are using. (Often the sequence starts with
-@kbd{@key{ESC} [}.) If Emacs understands your terminal type properly,
-it recognizes the character sequences forming function keys wherever
-they occur in a key sequence. Thus, for most purposes, you can
-pretend the function keys reach Emacs directly and ignore their
-encoding as character sequences.
-
- Key sequences can mix function keys and characters. For example, if
-your keyboard has a @key{Home} function key, Emacs also recognizes key
-sequences like @kbd{C-x @key{Home}}. You can even mix mouse events
-with keyboard events, but we recommend against it, because such key
-sequences are inconvenient to use.
-
- As a user, you can redefine any key, but it is usually best to stick
-to key sequences that consist of @kbd{C-c} followed by a letter (upper
-or lower case). These keys are ``reserved for users,'' so they won't
-conflict with any properly designed Emacs extension. The function
-keys @key{F5} through @key{F9} are also reserved for users. If you
-redefine some other key, your definition may be overridden by certain
-extensions or major modes which redefine the same key.
+can have bindings for them. Key sequences can mix function keys and
+characters. For example, if your keyboard has a @key{Home} function
+key, Emacs can recognize key sequences like @kbd{C-x @key{Home}}. You
+can even mix mouse events with keyboard events, such as
+@kbd{S-down-mouse-1}.
+
+ On text terminals, typing a function key actually sends the computer
+a sequence of characters; the precise details of the sequence depends
+on the function key and on the terminal type. (Often the sequence
+starts with @kbd{@key{ESC} [}.) If Emacs understands your terminal
+type properly, it automatically handles such sequences as single input
+events.
@node Prefix Keymaps
@subsection Prefix Keymaps
@subsection Local Keymaps
@cindex local keymap
- So far we have explained the ins and outs of the global map. Major
-modes customize Emacs by providing their own key bindings in @dfn{local
-keymaps}. For example, C mode overrides @key{TAB} to make it indent the
-current line for C code. Portions of text in the buffer can specify
-their own keymaps to substitute for the keymap of the buffer's major
-mode.
-
@cindex minor mode keymap
- Minor modes can also have local keymaps. Whenever a minor mode is
-in effect, the definitions in its keymap override both the major
-mode's local keymap and the global keymap.
-
- A local keymap can locally redefine a key as a prefix key by defining
-it as a prefix keymap. If the key is also defined globally as a prefix,
-then its local and global definitions (both keymaps) effectively
-combine: both of them are used to look up the event that follows the
-prefix key. Thus, if the mode's local keymap defines @kbd{C-c} as
-another keymap, and that keymap defines @kbd{C-z} as a command, this
-provides a local meaning for @kbd{C-c C-z}. This does not affect other
-sequences that start with @kbd{C-c}; if those sequences don't have their
-own local bindings, their global bindings remain in effect.
+ So far, we have explained the ins and outs of the global map. Major
+modes customize Emacs by providing their own key bindings in
+@dfn{local keymaps}. For example, C mode overrides @key{TAB} to make
+it indent the current line for C code. Minor modes can also have
+local keymaps; whenever a minor mode is in effect, the definitions in
+its keymap override both the major mode's local keymap and the global
+keymap. In addition, portions of text in the buffer can specify their
+own keymaps, which override all other keymaps.
+
+ A local keymap can redefine a key as a prefix key by defining it as
+a prefix keymap. If the key is also defined globally as a prefix, its
+local and global definitions (both keymaps) effectively combine: both
+definitions are used to look up the event that follows the prefix key.
+For example, if a local keymap defines @kbd{C-c} as a prefix keymap,
+and that keymap defines @kbd{C-z} as a command, this provides a local
+meaning for @kbd{C-c C-z}. This does not affect other sequences that
+start with @kbd{C-c}; if those sequences don't have their own local
+bindings, their global bindings remain in effect.
Another way to think of this is that Emacs handles a multi-event key
sequence by looking in several keymaps, one by one, for a binding of the
works, but it's good enough for understanding the results in ordinary
circumstances.
-@cindex rebinding major mode keys
- Most major modes construct their keymaps when the mode is used for
-the first time in a session. If you wish to change one of these
-keymaps, you must use the major mode's @dfn{mode hook}
-(@pxref{Hooks}).
-
-@findex define-key
- For example, the command @code{texinfo-mode} to select Texinfo mode
-runs the hook @code{texinfo-mode-hook}. Here's how you can use the hook
-to add local bindings (not very useful, we admit) for @kbd{C-c n} and
-@kbd{C-c p} in Texinfo mode:
-
-@example
-(add-hook 'texinfo-mode-hook
- '(lambda ()
- (define-key texinfo-mode-map "\C-cp"
- 'backward-paragraph)
- (define-key texinfo-mode-map "\C-cn"
- 'forward-paragraph)))
-@end example
-
@node Minibuffer Maps
@subsection Minibuffer Keymaps
@code{minibuffer-local-map} is used for ordinary input (no completion).
@item
@code{minibuffer-local-ns-map} is similar, except that @key{SPC} exits
-just like @key{RET}. This is used mainly for Mocklisp compatibility.
+just like @key{RET}.
@item
@code{minibuffer-local-completion-map} is for permissive completion.
@item
@cindex redefining keys, this session
The way to redefine an Emacs key is to change its entry in a keymap.
-You can change the global keymap, in which case the change is effective in
-all major modes (except those that have their own overriding local
-definitions for the same key). Or you can change the current buffer's
-local map, which affects all buffers using the same major mode.
+You can change the global keymap, in which case the change is
+effective in all major modes (except those that have their own
+overriding local bindings for the same key). Or you can change a
+local keymap, which affects all buffers using the same major mode.
+
+ In this section, we describe how to rebind keys for the present
+Emacs session. @xref{Init Rebinding}, for a description of how to
+make key rebindings affect future Emacs sessions.
@findex global-set-key
@findex local-set-key
Make @var{key} undefined locally (in the major mode now in effect).
@end table
- For example, suppose you like to execute commands in a subshell within
-an Emacs buffer, instead of suspending Emacs and executing commands in
-your login shell. Normally, @kbd{C-z} is bound to the function
-@code{suspend-emacs} (when not using the X Window System), but you can
-change @kbd{C-z} to invoke an interactive subshell within Emacs, by
-binding it to @code{shell} as follows:
+ For example, the following binds @kbd{C-z} to the @code{shell}
+command (@pxref{Interactive Shell}), replacing the normal global
+definition of @kbd{C-z}:
@example
M-x global-set-key @key{RET} C-z shell @key{RET}
@end example
@noindent
-@code{global-set-key} reads the command name after the key. After you
-press the key, a message like this appears so that you can confirm that
-you are binding the key you want:
+The @code{global-set-key} command reads the command name after the
+key. After you press the key, a message like this appears so that you
+can confirm that you are binding the key you want:
@example
Set key C-z to command:
@node Init Rebinding
@subsection Rebinding Keys in Your Init File
+@cindex rebinding major mode keys
@c This node is referenced in the tutorial. When renaming or deleting
@c it, the tutorial needs to be adjusted. (TUTORIAL.de)
If you have a set of key bindings that you like to use all the time,
-you can specify them in your initialization file by writing Lisp code
-(@pxref{Init File}).
+you can specify them in your initialization file by writing Lisp code.
+@xref{Init File}, for a description of the initialization file.
@findex kbd
There are several ways to write a key binding using Lisp. The
representation of a key sequence---similar to how we have written key
sequences in this manual---into a form that can be passed as an
argument to @code{global-set-key}. For example, here's how to bind
-@kbd{C-z} to @code{shell} (@pxref{Interactive Shell}):
+@kbd{C-z} to the @code{shell} command (@pxref{Interactive Shell}):
@example
(global-set-key (kbd "C-z") 'shell)
When the key sequence includes function keys or mouse button events,
or non-@acronym{ASCII} characters such as @code{C-=} or @code{H-a},
-you must use a vector to specify the key sequence. Each element in
-the vector stands for an input event; the elements are separated by
-spaces and surrounded by a pair of square brackets. If an element is
-a symbol, simply write the symbol's name---no other delimiters or
-punctuation are needed. If a vector element is a character, write it
-as a Lisp character constant: @samp{?} followed by the character as it
-would appear in a string. Here are some examples:
+you can use a vector to specify the key sequence. Each element in the
+vector stands for an input event; the elements are separated by spaces
+and surrounded by a pair of square brackets. If a vector element is a
+character, write it as a Lisp character constant: @samp{?} followed by
+the character as it would appear in a string. Function keys are
+represented by symbols (@pxref{Function Keys}); simply write the
+symbol's name, with no other delimiters or punctuation. Here are some
+examples:
@example
(global-set-key [?\C-=] 'make-symbolic-link)
Language and coding systems may cause problems with key bindings for
non-@acronym{ASCII} characters. @xref{Init Non-ASCII}.
+ As described in @ref{Local Keymaps}, major modes and minor modes can
+define local keymaps. These keymaps are constructed when the mode is
+used for the first time in a session. If you wish to change one of
+these keymaps, you must use the @dfn{mode hook} (@pxref{Hooks}).
+
+@findex define-key
+ For example, Texinfo mode runs the hook @code{texinfo-mode-hook}.
+Here's how you can use the hook to add local bindings for @kbd{C-c n}
+and @kbd{C-c p} in Texinfo mode:
+
+@example
+(add-hook 'texinfo-mode-hook
+ '(lambda ()
+ (define-key texinfo-mode-map "\C-cp" 'backward-paragraph)
+ (define-key texinfo-mode-map "\C-cn" 'forward-paragraph)))
+@end example
+
@node Modifier Keys
@subsection Modifier Keys
@cindex modifier keys
and does not apply to ``shifted'' versions of other keys; for
instance, @kbd{C-@@} is not the same as @kbd{C-2}.
- When you customize Emacs, you can make modified alphabetical
-characters case-sensitive. For instance, you could make @kbd{M-a} and
-@kbd{M-A} run different commands.
+ A @key{Control}-modified alphabetical character is always considered
+case-insensitive: Emacs always treats @kbd{C-A} as @kbd{C-a},
+@kbd{C-B} as @kbd{C-b}, and so forth. The reason for this is
+historical.
- As a special exception, a @key{Control}-modified alphabetical
-character is always case-insensitive, for historical reasons: Emacs
-always treats @kbd{C-A} as @kbd{C-a}, @kbd{C-B} as @kbd{C-b}, and so
-forth.
+ For all other modifiers, you can make the modified alphabetical
+characters case-sensitive when you customize Emacs. For instance, you
+could make @kbd{M-a} and @kbd{M-A} run different commands.
Although only the @key{Control} and @key{Meta} modifier keys are
commonly used, Emacs supports three other modifier keys. These are
Specify your own email address, if Emacs can't figure it out correctly.
@example
-(setq user-mail-address "rumsfeld@@torture.gov")
+(setq user-mail-address "cheney@@torture.gov")
@end example
Various Emacs packages that need your own email address use the value of
projects / emacs.git / commitdiff