Re: Entering emojis

[Eli Zaretskii]

> From: Lars Ingebrigtsen <larsi@gnus.org>
> Cc: Gregory Heytings <gregory@heytings.org>,  mattiase@acm.org,
>   emacs-devel@gnu.org,  schwab@linux-m68k.org,  stefankangas@gmail.com,
>   raman@google.com
> Date: Thu, 28 Oct 2021 23:40:44 +0200
> 
> Eli Zaretskii <eliz@gnu.org> writes:
> 
> > Yes, I know.  But ligatures are not the only way of handling this.
> > When a font produces a ligature, i.e. a precomposed glyph that should
> > be displayed instead of several characters, it produces a single font
> > glyph.  The other way is to produce several font glyphs, each one with
> > offsets relative to the base-line.  Emacs supports both ways.
> 
> Oh, I didn't know that Emacs had support for ligatures now -- last time
> I looked at it, it didn't seem to work.  Or am I misreading?

We have the infrastructure that supports ligatures in builds with
HarfBuzz since Emacs 27.  There's a TODO item which describes what is
left to do before we can claim a decent support for ligatures, not
just the potential for it.  Right now, to have ligatures, you need to
manually define character-composition rules for them, something that
is too low-level to advertise as a feature ready to be used.  And the
definitions of those rules should be specific to the font you are
using, because different fonts support different ligatures.  (Some
3rd-party packages use this infrastructure, but I have yet to see a
package that does it in a satisfactory manner, per the description in
TODO.)