Re: Using proportional (variable-width) fonts in Emacs23

[Eli Zaretskii <eliz@gnu.org>]

> From: Stefan Monnier <monnier@iro.umontreal.ca>
> Date: Thu, 31 Mar 2011 00:58:55 -0400
> 
> > Not necessarily.  In Emacs, we can specify that text be displayed
> > aligned to a specific width in pixels.  See the node "Specified Space"
> > in the ELisp manual.  Perhaps display of programming languages could
> > use this feature to align program source even with proportional fonts.
> 
> I don't think we have good support for that in the display engine right
> now, but we do have some amount of support for it and it's not used for
> that purpose, and I think there's a good reason: there is no place to
> store the necessary information in the file.  So while you might be able
> to do align on-demand and even maintain that alignment as the buffer is
> edited, it's difficult to infer the needed alignment from the source
> file: I think that the information present in the file is sufficient for
> 90% of the cases, but the remaining 10% is problematic (and even
> getting those 90% working might be dependent on the language, i.e. on
> the major-mode).

We do something very similar with fontification.  There's no reason,
at least not a-priori, that it won't work with alignment.