Re: Dependent colours

[Eli Zaretskii <eliz@gnu.org>]

> From: Lars Ingebrigtsen <larsi@gnus.org>
> Cc: emacs-devel@gnu.org
> Date: Thu, 14 Apr 2022 18:13:56 +0200
> 
> Eli Zaretskii <eliz@gnu.org> writes:
> 
> > But the result should be a face, right?  
> 
> It could be a face, but not necessarily.  Dynamically creating an SVG
> with a different foreground colour depending on the frame, for instance.

Are there any other examples besides the background of SVG?  Because
the latter is AFAIR very special, and we can now handle it through
faces as well.  So the question is: do we need to do this outside of
the faces realm?  I cannot think of any other case where we use colors
not via faces.

> > So you want an easy-to-use facility to create a face that depends on
> > the background-mode?  Or am I misunderstanding again?  And if I am
> > misunderstanding, can you please describe the use case in more detail?
> 
> defface is easy enough to use if you want to create a face, but here the
> interface we're presenting the user with is tied to colours, not faces.

Interactively or non-interactively?

Anyway, colors in Emacs are face attributes.