Re: x-font-family-list

[Chong Yidong]

Eli Zaretskii <address@hidden> writes:

> I don't understand this change:
>
>>      * xfaces.c (Fx_font_family_list): Function deleted.  Compatibility
>>      version moved to faces.el.
>
> This "compatibility version" is not compatible, AFAICS: it claims that
> none of the font families are fixed-pitch, and also assumes that some
> builds of Emacs don't have font-family-list fboundp, which is never
> true AFAIK.  The net effect is that in the --without-x and MS-DOS
> builds x-font-family-list now returns nil, whereas previously it was
> unbound in the --without-x build and on MS-DOS returned `("default" . t)'.
>
> What am I missing?  What was the purpose of this change?

The previous version of x-font-family-list (in xfaces.c) was broken---it
simply returned the return value of font-family-list, and so did not do
what the docstring said.  I noticed that when updating the font handling
documentation, so I made this change, but forgot to implement the
fixed-p part.  Thanks for spotting the omission

> If the value of this function is not important at all, let's delete it
> completely.  If it _is_ important, then let's make the replacement
> really compatible, which means at the very least make the cdr of the
> cons cells it returns be non-nil for fixed-pitch font families.

I don't think it's important, but am not sure whether there is any
external code relying on it.  Normally, this means that we should try to
change the compatibility function and make it compatible.  But, I don't
know a simple way of computing whether a font is fixed-pitch using the
new font code, without jumping through some ugly hoops (e.g., somehow
turning each family name into an xlfd and examining its "monospace"
entry).  If no one can suggest a good method, let's just delete the
function.