Re: Prefix Argument and optional argument

[Christopher Dimech]

> Sent: Friday, July 08, 2022 at 12:53 AM
> From: "Michael Heerdegen" <michael_heerdegen@web.de>
> To: "Christopher Dimech" <dimech@gmx.com>
> Cc: help-gnu-emacs@gnu.org
> Subject: Re: Prefix Argument and optional argument
>
> Christopher Dimech <dimech@gmx.com> writes:
> 
> > Is the error because one can either use the prefix argument C-u M-x
> > poke or use just M-x poke?  Or something else?
> 
> Which error?
> 
> Michael.

Have recently seen that compiling

(defun poke (prefix)
  "TODO."
  (interactive "P")
...)

gives 

Warning: misplaced interactive spec: ‘(interactive P)’

Is this associated with trying to call the function non-interactively
or because the prefix (C-u) is not always used when running the function
interactively?