Subject: Re: bug#34852: 26.1; seq-intersection ignores nil as element

From: Stefan Monnier <[email-masked]>
Date: Thu, 14 Mar 2019 17:43:16 -0400

> If ELT=nil, seq-contains currently returns nil anyway;

That's true when `testfn` is nil, but not if you provide
your own `testfn`.

        Stefan