elisp: Disabling Commands
20.14 Disabling Commands
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“Disabling a command” marks the command as requiring user confirmation
before it can be executed. Disabling is used for commands which might
be confusing to beginning users, to prevent them from using the commands
by accident.
The low-level mechanism for disabling a command is to put a non-‘nil’
‘disabled’ property on the Lisp symbol for the command. These
File::) with Lisp expressions such as this:
(put 'upcase-region 'disabled t)
For a few commands, these properties are present by default (you can
remove them in your init file if you wish).
If the value of the ‘disabled’ property is a string, the message
saying the command is disabled includes that string. For example:
(put 'delete-region 'disabled
"Text deleted this way cannot be yanked back!\n")
(emacs)Disabling, for the details on what happens when a
disabled command is invoked interactively. Disabling a command has no
effect on calling it as a function from Lisp programs.
-- Command: enable-command command
Allow COMMAND (a symbol) to be executed without special
confirmation from now on, and alter the user’s init file (
Init File) so that this will apply to future sessions.
-- Command: disable-command command
Require special confirmation to execute COMMAND from now on, and
alter the user’s init file so that this will apply to future
sessions.
-- Variable: disabled-command-function
The value of this variable should be a function. When the user
invokes a disabled command interactively, this function is called
instead of the disabled command. It can use ‘this-command-keys’ to
determine what the user typed to run the command, and thus find the
command itself.
The value may also be ‘nil’. Then all commands work normally, even
disabled ones.
By default, the value is a function that asks the user whether to
proceed.
Info Catalog
elisp: Recursive Editing
elisp: Command Loop
elisp: Command History