Re: +face-remapping-20040505-0.patch

[Stefan Monnier <monnier@iro.umontreal.ca>]

>     I still think that face-remapping should rely on face-inheritance rather
>     than allow mapping a face to several (merged) faces.
> I am not quite sure what change you are proposing.
> If you are saying that the feature of remapping X to (Y Z)
> should be removed, and instead the user should have to
> define W as (Y Z) then remap X to W, I think that is
> a loss of convenience with nearly zero gain in simplicity.

Well, maybe it doesn't make the code simpler, I don't know.
But it does simplify the explanation of what (face-attribute X :foo)
returns (since we've already dealt with the issue of whether it returns the
info corresponding to Y or to Y+Z or to Y+Z+default).

Also the added convenience of not having to define W might not be
that great.  After all, I expect 99% of the remapping to just be from
X to Y.  Also the intermediate W might/should be added anyway just to make
easier for the user to customize the resulting face.

Maybe it doesn't make the current implementation simple, but it at least
makes the concept simpler.  OTOH, that's assuming that "99% of the remapping
[will] just be from X to Y".  This 99% assumption assumes that mapping X
to (X Y) doesn't work, tho.

OTOH, I must say that the most important use of this remapping facility
would be to tweak faces in various modes, so mapping X to (X Y) would be
the most useful application, if not the only one.  So maybe we should
have face-addition-alist rather face-remapping-alist so we could just put
(region . bold) in order to add bold to the region face.


        Stefan