Hi there,
I just stumbled over the lack of a multiple-value-or in CL, so here's a patch hat implement it in alexandria (with the first value specifying which value's non-NIL-ness to consider):
It may look horrifying, but it allows pleasant things like:
(multiple-value-or 1 (gethash key table) (gethash key alternative- table))
and other niceties.
Hope you like it,