Re: Making `x-underline-at-descent-line' a face attribute

[Eli Zaretskii]

> From: Po Lu <luangruo@yahoo.com>
> Cc: emacs-devel@gnu.org
> Date: Fri, 07 Jan 2022 15:14:45 +0800
> 
> Thanks, one last question (before I start to implement this): what would
> you recommend as a special value of `:underline'?
> 
> Would it be okay to add a new property to the property list that is
> already accepted as such a value?

Yes, something like

   (:color COLOR :style STYLE :position POS)

where POS can be t (with the same effect as non-nil value of
x-underline-at-descent-line) or (if you want to get fancy) a number,
to specify an explicit offset from the baseline.