Re: master 396355f: Re-fix charset issues when yanking non-plain-text elements

[Eli Zaretskii]

> From: Lars Ingebrigtsen <larsi@gnus.org>
> Cc: emacs-devel@gnu.org
> Date: Thu, 11 Nov 2021 12:54:17 +0100
> 
> >> +                    ;; Guess at the charset for types like text/html
> >> +                    ;; -- it can be anything, and different
> >> +                    ;; applications use different encodings.
> >> +                    ((string-match-p "\\`text/" (symbol-name data-type))
> >> +                     (decode-coding-string
> >> +                      data (car (detect-coding-string data))))
> >
> > Did you really need the explicit call to detect-coding-string?  AFAIR,
> > decode-coding-string does that automatically if needed.  Did that fail
> > in some case?
> 
> Can you give a nil to decode-coding-string as the coding system?  It's
> not documented.

If by nil you means "don't know", then I think you should use
'undecided instead.  That's exactly what 'undecided means.