Re: Making a function than can only be used interactively

[Tassilo Horn <tsdh@gnu.org>]

carlmarcos--- via Users list for the GNU Emacs text editor <help-gnu-emacs@gnu.org> writes:

>>> Is it possible to make an interactive function than can only be used
>>> interactively?
>>
>> I'm not sure I understand your question. A function, that may be
>> called interactively, is called a "command" in Emacs.  And a command
>> can definitely be called interactively, either by using it's name
>> (using M-x) or binding it to a key.
>>
> I do not want people to use the function non-interactively.

How restrictive is that! :-)

--8<---------------cut here---------------start------------->8---
(defun only-interactive ()
  (interactive)
  (if (called-interactively-p 'interactive)
      42
    (error "You may not call me")))

(only-interactive)
;;=> Debugger entered--Lisp error: (error "You may not call me")

(call-interactively 'only-interactive)
;;=> 42

(cl-letf (((symbol-function 'called-interactively-p)
           (lambda (&rest _args) t)))
  (only-interactive))
;;=> 42
--8<---------------cut here---------------end--------------->8---

So as you see, there are many ways around it.

Bye,
Tassilo