Re: tabulated-list-init-header and glyphless-char-display

[Chong Yidong]

Eli Zaretskii <address@hidden> writes:

>> Hmm... so IIUC we distinguish between "glyphless" and "without a font".
>> Where do we explain the difference between the two, and is there a good
>> reason to distinguish the two cases?
>
> No, "glyphless" and "without a font" are (and should be) synonyms.
> Except that on a text terminal, "without a font" means "cannot be
> encoded for the current terminal encoding".

That's apparently not how glyphless-char-display works.  The docstring
is a bit ambiguous, but glyphless-char-display actually *defines* the
characters that cannot be displayed in an ordinary way.  For instance,
if you do (aset glyphless-char-display ?a 'empty-box), that tells Emacs
that "a" is a glyphless character, and causes all "a"'s to be displayed
as empty boxes.

What you are thinking of is a char table that says "how should we
display character C if it has no font", but AFAICT there is currently no
such facility.  There is only the extra slot of glyphless-char-display,
which handles all characters with no font without discriminating.