Re: M-. vs C-h o

[Eli Zaretskii]

> From: Hongyi Zhao <hongyi.zhao@gmail.com>
> Date: Fri, 22 Oct 2021 08:28:48 +0800
> 
> So, I want to know the correspondence of the following two descriptions:
> 
> DEFUN ("mapc", Fmapc, Smapc, 2, 2, 0,
> 
> and
> 
> (mapc FUNCTION SEQUENCE)

'mapc' is a "primitive", i.e. a Lisp-callable function that's
implemented in C.  I suggest to read the node "Writing Emacs
Primitives" in the ELisp manual, it will explain that to you.