Eli Zaretskii <eliz@gnu.org> writes:

> > [...] repeating a test.  Is this what you prefer?
>
> Yes, I think so.  And you could perhaps avoid repetition of
> (cdr binding) by saving the result of (null (cdr binding)) in
> a local variable.

I went with a separate `cond' branch added instead, I think this is even
simpler.  Ok?