Re: Ligature support

[Lars Ingebrigtsen]

Eli Zaretskii <eliz@gnu.org> writes:

> How many ligatures are there in the best of all fonts?  If the number
> of the ligatures is not too large, then passing them to the shaper may
> not be such a terrible idea.

I don't really know -- my test font has 27 ligatures, apparently, but
some of the more fun programming fonts have at least a hundred, I think.
And there's fonts that turn things like :warning: into its own glyph,
using the ligature mechanism, and who knows how many of those there may
be.

> So I think we should first consider which ligatures we'd like to
> support, and whether the answer differs depending on the major mode.
> For example, ligatures like ==> etc. are relevant to prog-mode modes,
> but probably not to text modes.  By contrast, "ff" and "fi" are
> relevant only to text mode, I think.

I think we want to support all ligatures the font supports (in general).
But as you say, we may not want to switch all the ligatures on in all
modes -- but I'm not really sure about that, either.  If a person is
using the Firabase font (or whatever it was called), they presumably do
so because they want to get all the funny glyphs everywhere (that they
use that font).

But it's certainly possible -- having a switch to tweak which ligatures
should be active on a per-mode/buffer basis is something we'd need to
look at.  I think we can look at that after we actually have ligatures
displayed at all, though.  😀

-- 
(domestic pets only, the antidote for overdose, milk.)
   bloggy blog: http://lars.ingebrigtsen.no