Re: Unicode confusables and reordering characters considered harmful

[Gregory Heytings]

> > > It could, but I don't think we should install such features.
> >
> > Why not?
>
> Because it doesn't pass my quality-control tests.

That's a reason ;-)

> > Is this not simply an improved (and built-in) version of your initial 
> > suggestion to use glyphless-char-display?
>
> glyphless-char-display already exists and is built-in.  People who want 
> to have these characters stand out for some reason can use it, that's 
> why it is open to customization.  What you propose is "yet another 
> mechanism similar to glyphless-char-display", and I don't see why we 
> should have this for a small group of characters.  We already have a 
> small mess because display-tables and glyphless-char-display produce a 
> race; I certainly don't think we should introduce yet another, third 
> mechanism for a similar purpose.

I don't really see why this is a third mechanism, buffer-display-table 
already exists and is built-in, too.  Both are char tables.  I always 
thought that glyphless-char-display was more or less the global equivalent 
of buffer-display-table, but apparently I'm missing something.

> I could consider adding an additional METHOD to those we already support 
> there, if someone thinks the existing ones are insufficient. Not sure if 
> this is needed, but it at least makes some sense, assuming the proposal 
> would be reasonable and not limited to a small group of codepoints.
>
> > Except that glyphless-char-display is global (whereas
> > buffer-display-table is buffer-local), and that a tofu is not as
> > visible as a character highlighted with the font-lock-warning-face.
>
> Patches to allow glyphless display to be controlled on a buffer-local
> basis would be welcome, I think this would be a good enhancement.