bug#57079: 29.0.50; Performance of seq-uniq is not very good

[Eli Zaretskii]

> From: Lars Ingebrigtsen <larsi@gnus.org>
> Cc: Stefan Kangas <stefan@marxist.se>,  57079@debbugs.gnu.org
> Date: Tue, 09 Aug 2022 18:57:33 +0200
> 
> Eli Zaretskii <eliz@gnu.org> writes:
> 
> > What's wrong with using delete-dups for your cases above?
> 
> delete-dups is destructive.  You can copy the list first, of course, but
> seq-uniq should be much faster than it is.

How much faster?  Using copy-sequence and delete-dups is 7 times
faster here than seq-uniq and twice faster than
gnus-delete-duplicates.