编辑代码

(defun deep-member(el a-list)
   (cond ((null a-list) NIL)
   ((listp (car a-list)) (or (deep-memberel (car a-list)) (deep-memberel (cdr a-list))))
   (T (or (equal el (car a-list)) (deep-memberel (cdr a-list))))
 )  
)
(print (deep-member 'a '(b '(a c))))