bug#56418: Add duplicate-dwim [PATCH]

[Eli Zaretskii]

> Cc: 56418@debbugs.gnu.org
> From: Richard Stallman <rms@gnu.org>
> Date: Sun, 31 Jul 2022 23:33:22 -0400
> 
>   > Roughly, duplicate-dwim is to duplicate-line as upcase-dwim is to 
> upcase-word. Ie, the -dwim commands operate on the region if active.
> 
> I think there are already several commands that operate on the region
> if it is active, otherwise on some other textual unit.  Would it be
> bad for duplicate-line to do this?  Then we wouldn't need a separate
> duplicate-dwim.

That was suggested, but turned out to be too controversial.