@c -*-texinfo-*-
@c This is part of the GNU Emacs Lisp Reference Manual.
-@c Copyright (C) 1990, 1991, 1992, 1993, 1994, 1995, 1998, 1999
+@c Copyright (C) 1990, 1991, 1992, 1993, 1994, 1995, 1998, 1999, 2004
@c Free Software Foundation, Inc.
@c See the file elisp.texi for copying conditions.
@setfilename ../info/commands
This section describes how to write the @code{interactive} form that
makes a Lisp function an interactively-callable command, and how to
-examine a commands's @code{interactive} form.
+examine a command's @code{interactive} form.
@defspec interactive arg-descriptor
@cindex argument descriptors
@cindex examining the @code{interactive} form
@defun interactive-form function
-This function returns the @code{interactive} form of @var{function}. If
-@var{function} is a command (@pxref{Interactive Call}), the value is a
-list of the form @code{(interactive @var{spec})}, where @var{spec} is
-the descriptor specification used by the command's @code{interactive}
-form to compute the function's arguments. If @var{function} is not a
-command, @code{interactive-form} returns @code{nil}.
+This function returns the @code{interactive} form of @var{function}.
+If @var{function} is an interactively callable function
+(@pxref{Interactive Call}), the value is the command's
+@code{interactive} form @code{(interactive @var{spec})}, which
+specifies how to compute its arguments. Otherwise, the value is
+@code{nil}. If @var{function} is a symbol, its function definition is
+used.
@end defun
@node Interactive Codes
parentheses and brackets) do not do so here. Prompt.
@item v
-A variable declared to be a user option (i.e., satisfying the predicate
-@code{user-variable-p}). @xref{High-Level Completion}. Existing,
+A variable declared to be a user option (i.e., satisfying the
+predicate @code{user-variable-p}). This reads the variable using
+@code{read-variable}. @xref{Definition of read-variable}. Existing,
Completion, Prompt.
@item x
@defun call-interactively command &optional record-flag keys
This function calls the interactively callable function @var{command},
reading arguments according to its interactive calling specifications.
-An error is signaled if @var{command} is not a function or if it cannot
-be called interactively (i.e., is not a command). Note that keyboard
-macros (strings and vectors) are not accepted, even though they are
-considered commands, because they are not functions.
+It returns whatever @var{command} returns. An error is signaled if
+@var{command} is not a function or if it cannot be called
+interactively (i.e., is not a command). Note that keyboard macros
+(strings and vectors) are not accepted, even though they are
+considered commands, because they are not functions. If @var{command}
+is a symbol, then @code{call-interactively} uses its function definition.
@cindex record command history
If @var{record-flag} is non-@code{nil}, then this command and its
The argument @var{keys}, if given, specifies the sequence of events to
supply if the command inquires which events were used to invoke it.
+If @var{keys} is omitted or @code{nil}, the return value of
+@code{this-command-keys} is used. @xref{Definition of this-command-keys}.
@end defun
@defun command-execute command &optional record-flag keys special
A string or vector as @var{command} is executed with
@code{execute-kbd-macro}. A function is passed to
-@code{call-interactively}, along with the optional @var{record-flag}.
+@code{call-interactively}, along with the optional @var{record-flag}
+and @var{keys}.
A symbol is handled by using its function definition in its place. A
symbol with an @code{autoload} definition counts as a command if it was
definition is handled by loading the specified library and then
rechecking the definition of the symbol.
-The argument @var{keys}, if given, specifies the sequence of events to
-supply if the command inquires which events were used to invoke it.
-
The argument @var{special}, if given, means to ignore the prefix
argument and not clear it. This is used for executing special events
(@pxref{Special Events}).
@end defvar
@defun this-command-keys
+@anchor{Definition of this-command-keys}
This function returns a string or vector containing the key sequence
that invoked the present command, plus any previous commands that
-generated the prefix argument for this command. The value is a string
-if all those events were characters. @xref{Input Events}.
+generated the prefix argument for this command. However, if the
+command has called @code{read-key-sequence}, it returns the last read
+key sequence. @xref{Definition of read-key-sequence}. The value is a
+string if all events in the sequence were characters that fit in a
+string. @xref{Input Events}.
@example
@group
@end defun
@tindex clear-this-command-keys
-@defun clear-this-command-keys
+@defun clear-this-command-keys &optional keep-record
This function empties out the table of events for
-@code{this-command-keys} to return, and also empties the records that
-the function @code{recent-keys} (@pxref{Recording Input}) will
-subsequently return. This is useful after reading a password, to
-prevent the password from echoing inadvertently as part of the next
-command in certain cases.
+@code{this-command-keys} to return. Unless @var{keep-record} is
+non-@code{nil}, it also empties the records that the function
+@code{recent-keys} (@pxref{Recording Input}) will subsequently return.
+This is useful after reading a password, to prevent the password from
+echoing inadvertently as part of the next command in certain cases.
@end defun
@defvar last-nonmenu-event
generated, but if that frame has redirected input focus to another
frame, the value is the frame to which the event was redirected.
@xref{Input Focus}.
+
+If the last event came from a keyboard macro, the value is @code{macro}.
@end defvar
@node Adjusting Point
@example
(@var{window} @var{pos-or-area} (@var{x} . @var{y}) @var{timestamp}
- @var{object} @var{text-pos} (@var{col} . @var{row})
+ @var{object} @var{text-pos} (@var{col} . @var{row})
@var{image} (@var{dx} . @var{dy}) (@var{width} . @var{height}))
@end example
(not a repeat event), the value is 1.
@end defun
-@defvar double-click-fuzz
+@defopt double-click-fuzz
To generate repeat events, successive mouse button presses must be at
approximately the same screen position. The value of
@code{double-click-fuzz} specifies the maximum number of pixels the
-mouse may be moved between two successive clicks to make a
-double-click.
-@end defvar
+mouse may be moved (horizontally or vertically) between two successive
+clicks to make a double-click.
-@defvar double-click-time
+This variable is also the threshold for motion of the mouse to count
+as a drag.
+@end defopt
+
+@defopt double-click-time
To generate repeat events, the number of milliseconds between
successive button presses must be less than the value of
@code{double-click-time}. Setting @code{double-click-time} to
@code{nil} disables multi-click detection entirely. Setting it to
@code{t} removes the time limit; Emacs then detects multi-clicks by
position only.
-@end defvar
+@end defopt
@node Motion Events
@subsection Motion Events
modifiers are symbols; they include @code{shift}, @code{control},
@code{meta}, @code{alt}, @code{hyper} and @code{super}. In addition,
the modifiers list of a mouse event symbol always contains one of
-@code{click}, @code{drag}, and @code{down}.
+@code{click}, @code{drag}, and @code{down}. For double or triple
+events, it also contains @code{double} or @code{triple}.
-The argument @var{event} may be an entire event object, or just an event
-type.
+The argument @var{event} may be an entire event object, or just an
+event type. If @var{event} is a symbol that has never been used in an
+event that has been read as input in the current Emacs session, then
+@code{event-modifiers} can return @code{nil}, even when @var{event}
+actually has modifiers.
Here are some examples:
@example
(event-modifiers ?a)
@result{} nil
+(event-modifiers ?A)
+ @result{} (shift)
(event-modifiers ?\C-a)
@result{} (control)
(event-modifiers ?\C-%)
@defun event-basic-type event
This function returns the key or mouse button that @var{event}
-describes, with all modifiers removed. For example:
+describes, with all modifiers removed. The @var{event} argument is as
+in @code{event-modifiers}. For example:
@example
(event-basic-type ?a)
@defun event-convert-list list
This function converts a list of modifier names and a basic event type
-to an event type which specifies all of them. For example,
+to an event type which specifies all of them. The basic event type
+must be the last element of the list. For example,
@example
(event-convert-list '(control ?a))
@cindex mouse event, timestamp
@cindex timestamp of a mouse event
-@defun posn-timestamp
+@defun posn-timestamp position
Return the timestamp in @var{position}. This is the time at which the
event occurred, in milliseconds.
@end defun
@defun read-key-sequence prompt
@cindex key sequence
+@anchor{Definition of read-key-sequence}
This function reads a key sequence and returns it as a string or
vector. It keeps reading events until it has accumulated a complete key
sequence; that is, enough to specify a non-prefix command using the
-currently active keymaps.
+currently active keymaps. (Remember that a key sequence that starts
+with a mouse event is read using the keymaps of the buffer in the
+window that the mouse was in, not the current buffer.)
If the events are all characters and all can fit in a string, then
@code{read-key-sequence} returns a string (@pxref{Strings of Events}).
The lowest level functions for command input are those that read a
single event.
+None of the three functions below suppresses quitting.
+
@defun read-event &optional prompt inherit-input-method
This function reads and returns the next event of command input, waiting
if necessary until an event is available. Events can come directly from
moves the cursor temporarily to the echo area, to the end of any message
displayed there. Otherwise @code{read-event} does not move the cursor.
-If @code{read-event} gets an event that is defined as a help character, in
-some cases @code{read-event} processes the event directly without
+If @code{read-event} gets an event that is defined as a help character,
+then in some cases @code{read-event} processes the event directly without
returning. @xref{Help Functions}. Certain other events, called
@dfn{special events}, are also processed directly within
@code{read-event} (@pxref{Special Events}).
This function is like @code{read-char}, except that if the first
character read is an octal digit (0-7), it reads any number of octal
digits (but stopping if a non-octal digit is found), and returns the
-character represented by that numeric character code.
+character represented by that numeric character code. If the
+character that terminates the sequence of octal digits is @key{RET},
+it is discarded. Any other terminating character is used as input
+after this function returns.
Quitting is suppressed when the first character is read, so that the
user can enter a @kbd{C-g}. @xref{Quitting}.
@group
---------- Echo Area ----------
-What character-@kbd{177}
+What character @kbd{1 7 7}-
---------- Echo Area ----------
@result{} 127
@cindex special events
Special events are handled at a very low level---as soon as they are
read. The @code{read-event} function processes these events itself, and
-never returns them.
+never returns them. Instead, it keeps waiting for the first event
+that is not special and returns that one.
Events that are handled in this way do not echo, they are never grouped
into key sequences, and they never appear in the value of
non-@code{nil}, then @code{quit-flag} has no special effect.
@end defvar
+@defmac with-local-quit forms@dots{}
+This macro executes @var{forms} in sequence, but allows quitting, at
+least locally, within @var{body} even if @code{inhibit-quit} was
+non-@code{nil} outside this construct. It returns the value of the
+last form in @var{forms}.
+
+If @code{inhibit-quit} is @code{nil} on entry to @code{with-local-quit},
+it only executes the @var{forms}, and setting @code{quit-flag} causes
+a normal quit. However, if @code{inhibit-quit} is non-@code{nil} so
+that ordinary quitting is delayed, a non-@code{nil} @code{quit-flag}
+triggers a special kind of local quit. This ends the execution of
+@var{forms} and exits the @code{with-local-quit} form with
+@code{quit-flag} still non-@code{nil}, so that another (ordinary) quit
+will happen as soon as that is allowed. If @code{quit-flag} is
+already non-@code{nil} at the beginning of @var{forms}, the local quit
+happens immediately and they don't execute at all.
+
+This macro is mainly useful in functions that can be called from
+timers, @code{pre-command-hook}, @code{post-command-hook} and other
+places where @code{inhibit-quit} is normally bound to @code{t}.
+@end defmac
+
@deffn Command keyboard-quit
This function signals the @code{quit} condition with @code{(signal 'quit
nil)}. This is the same thing that quitting does. (See @code{signal}
programs.
@deffn Command enable-command command
-Allow @var{command} to be executed without special confirmation from now
-on, and (if the user confirms) alter the user's init file (@pxref{Init
+Allow @var{command} (a symbol) to be executed without special
+confirmation from now on, and alter the user's init file (@pxref{Init
File}) so that this will apply to future sessions.
@end deffn
@deffn Command disable-command command
Require special confirmation to execute @var{command} from now on, and
-(if the user confirms) alter the user's init file so that this
-will apply to future sessions.
+alter the user's init file so that this will apply to future sessions.
@end deffn
@defvar disabled-command-hook
command, and thus find the command itself. @xref{Hooks}.
By default, @code{disabled-command-hook} contains a function that asks
-the user whether to proceed.
+the user whether to proceed. If the value is @code{nil}, then all
+commands work normally, even disabled ones.
@end defvar
@node Command History
events. Don't confuse keyboard macros with Lisp macros
(@pxref{Macros}).
-@defun execute-kbd-macro kbdmacro &optional count
+@defun execute-kbd-macro kbdmacro &optional count loopfunc
This function executes @var{kbdmacro} as a sequence of events. If
@var{kbdmacro} is a string or vector, then the events in it are executed
exactly as if they had been input by the user. The sequence is
executed once. If it is 0, @var{kbdmacro} is executed over and over until it
encounters an error or a failing search.
+If @var{loopfunc} is non-@code{nil}, it is a function that is called,
+without arguments, prior to each iteration of the macro. If
+@var{loopfunc} returns @code{nil}, then this stops execution of the macro.
+
@xref{Reading One Event}, for an example of using @code{execute-kbd-macro}.
@end defun
-@defvar executing-macro
+@defvar executing-kbd-macro
This variable contains the string or vector that defines the keyboard
macro that is currently executing. It is @code{nil} if no macro is
currently executing. A command can test this variable so as to behave
@end defvar
@defvar defining-kbd-macro
-This variable indicates whether a keyboard macro is being defined. A
-command can test this variable so as to behave differently while a macro
-is being defined. The commands @code{start-kbd-macro} and
-@code{end-kbd-macro} set this variable---do not set it yourself.
+This variable is non-@code{nil} if and only if a keyboard macro is
+being defined. A command can test this variable so as to behave
+differently while a macro is being defined. The commands
+@code{start-kbd-macro} and @code{end-kbd-macro} set this variable---do
+not set it yourself.
The variable is always local to the current terminal and cannot be
buffer-local. @xref{Multiple Displays}.
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