Elisp: how to avoid "functions are not known to be defined" when byte-compiling?

Question

My package, lispy, uses a function from ace-jump-mode. I'm still thinking if I should use ;; Package-Requires: cookie or featurep for it, but the main issue is that I want a clean byte-compile with emacs -q.

I thought that this should eliminate the byte-compilation warning:

(declare-function ace-jump-char-mode "ext:ace-jump-mode")

But it's not the case. Any thoughts on this?

Exactly, the warning is "the following functions are not known to be defined: ace-jump-char-mode, helm".

Answer 1

If that function is likely to be used in most cases where lispy is used, then you shoud just use something like (require 'ext:ace-jump-mode).