(defun palindromep (x)
(append ?a (?b . ?c) ?.x) ; note "?.x" reference
(or (reverse ?a ?c)
(reverse ?a (?b . ?c)))))
(palindromep '(yes no maybe))
(palindromep '(yes no maybe no yes))
The body of a
if it succeeds and a non-local exit is not executed. It returns nil on failure.