bug#47712: 27.1; Provide `string-display-width` function, which takes properties into account, `substring-width`

[Daniel Mendler]

On 4/12/21 7:09 PM, Eli Zaretskii wrote:
> > Cc: 47712@debbugs.gnu.org
> > From: Daniel Mendler <mail@daniel-mendler.de>
> > Date: Mon, 12 Apr 2021 16:36:05 +0200
> >
> > One may still discuss the implementation of a
> > `substring-width` API which generalizes `string-width`.
> >
> > (defun string-width (s)
> >     (substring-width s 0 (length s)))
> >
> > (defun substring-width (s a b)
> >     (string-width (substring s a b)))
>
> Why not simply extend string-width to accept 2 optional arguments?

I agree, that is better.