Re: Emacs pretest: highlight line number in display-line-numbers-mode?

[Eli Zaretskii <eliz@gnu.org>]

> Date: Fri, 20 Oct 2017 08:18:07 -0700 (PDT)
> From: Drew Adams <drew.adams@oracle.com>
> 
> > > >   . using a different face makes redisplay slightly slower
> > > >     (because it disallows some redisplay optimizations)
> > >
> > > Would those optimizations still be available if a
> > > user chose the same face for both (but the faces
> > > were different by default)?
> 
> ?
> 
> I guess you are confirming that the optimizations you
> spoke of are a red herring here:

It's not a red herring, you can see that in the code.

> they would anyway be available whenever someone customizes the
> current-line face to have the same appearance as the other-lines
> face.

The current-line face has the same appearance by default, making those
optimizations possible.  When the appearance is different, the
optimizations are disabled.  I hope what I say is now perfectly clear.

It is not clear to me what change you are lobbying for, except for
changing the defaults, which is something that was already asked and
answered.

> There are two faces, but they have the same appearance by default.
> That's the misdesign.

And as I already said, this "misdesign" has a good reason, so the
"mis" part is uncalled for.  You might disagree with my design, but
please don't use denigrating terms just because you do.

In any case, we already have several other faces that by default look
the same, so this is not an odd case.

> Please consider giving them a different appearance by
> default.

I already explained why I didn't think this was a good idea.  What is
the purpose of repeating the same request?