;; Key can legally be NIL, but if it's NIL for sure we pretend it's
;; not there at all. If it might be NIL, make up a form to that
;; ensures it is a function.
;; Key can legally be NIL, but if it's NIL for sure we pretend it's
;; not there at all. If it might be NIL, make up a form to that
;; ensures it is a function.