bug#17836: 24.3; `describe-fontset' confused about e.g. ?\C-@

[Eli Zaretskii]

> Date: Mon, 23 Jun 2014 19:17:01 +0300
> From: Eli Zaretskii <eliz@gnu.org>
> Cc: 17836@debbugs.gnu.org
> 
> > From: Samuel Bronson <naesten@gmail.com>
> > Date: Sun, 22 Jun 2014 21:57:07 -0400
> > 
> > Fontset: 
> > -misc-fixed-medium-r-semicondensed--13-*-*-*-*-*-fontset-xterm.default
> > CHAR RANGE (CODE RANGE)
> >     FONT NAME (REQUESTED and [OPENED])
> > C-@ .. � (#x43 .. #x10FFFF)
> >     -Misc-Fixed-medium-r-semicondensed--13-*-75-75-c-120-ISO10646-1
> > --8<---------------cut here---------------end--------------->8---
> > 
> > Notice how #x43 is NOT a representation of `?\C-@' but, in fact, of
> > `?C'?
> 
> That's because print-fontset-element does this:
> 
>   (beginning-of-line)
>   (let ((from (following-char))
> 
> IOW, it assumes that there's a single character there, not a
> human-readable description of a character, such as "C-@".
> 
> How about submitting a patch that uses 'kbd', say?

Or maybe describe-vector should accept 2 more arguments and pass it to
print-fontset-element.