Undefined-function error about function called by my function

Question

I have recently moved to emacs as my mail client. I am using message-mode to write and send email through notmuch. Specifically, the major mode is called Message[Notmuch].

I would like to remap C-c C-c (mail-send-and-exit) and C-c C-s (mail-send) to safe analogues that require a confirmation in the minibuffer before the email is sent. So far I have:

(defun safe-mail-send-and-exit ()
  (interactive)
  (if (string-equal (read-from-minibuffer "Are you sure? ") "yes")
      (mail-send-and-exit)
    (message "Not sent!")))

When I call this function within message-mode, I get an error:

Symbol’s function definition is void: mail-send-and-exit

How can I pass the context of the email and the mode to my function?

In your question, you refer to `send-mail-and-exit` but in your code you refer to `mail-send-and-exit`. Maybe that's why it can't find mail-send-and-exit. Unfortunately, I'm not that familiar with [notmuch](https://notmuchmail.org/). — g-gundam, Dec 08 '22 at 14:53
Hey, sorry, just a typo on my part in the post. Those should be `mail-send` and `mail-send-and-exit`, I'll edit the original post. — johngarg, Dec 08 '22 at 14:59
Emacs is telling you that function doesn't exist, so let's try to find the right one. Temporarily undo your remapping of `C-c C-c` and then figure out what function it was originally bound to by doing `C-h k` and then `C-c C-c`. I bet it'll be something other than `mail-send-and-exit`. — g-gundam, Dec 08 '22 at 15:12
Just out of curiosity, what was the function it was bound to? — g-gundam, Dec 08 '22 at 15:33
Functions in Emacs Lisp are globally scoped, so if the function is defined at all, it will be available everywhere. — NickD, Dec 08 '22 at 16:19

score 2 · Answer 1 · answered Dec 08 '22 at 18:07

Put (require 'THE-LIBRARY) inside your definition of safe-mail-send-and-exit, at the beginning (just after (interactive), where THE-LIBRARY is the library that defines function mail-send-and-exit.

(defun safe-mail-send-and-exit ()
  (interactive)
  (require 'THE-LIBRARY) ; Replace THE-LIBRARY with the right library name.
  (if (string-equal (read-from-minibuffer "Are you sure? ") "yes")
      (mail-send-and-exit)
    (message "Not sent!")))

Or else ensure that you load that library before defining (or at least before invoking) that function. E.g.:

(with-eval-after-load THE-LIBRARY
  (defun safe-mail-send-and-exit ()
   ;; ...
   ))

Not part of your question, but consider replacing this:

(string-equal (read-from-minibuffer "Are you sure? ") "yes")

with just this:

(yes-or-no-p "Are you sure? ")

Undefined-function error about function called by my function

1 Answers1