LispForum

Yeah, your code looks a lot like Scheme in Common Lisp ... Anyway, maybe what you want is something like this~ (defun make-set (x) (cond ((endp x) x) (t (adjoin (first x) (make-set (rest x)))))) (defun string-set-exclusive-or (lhs rhs) (coerce (set-exclusive-or (make-set (coerce lhs 'list)) (make-se...

Maybe represent those items with an a-list or something like that will be easier.