CL-USER> (maplist (lambda (list) (cons 0 list)) '(1 2 3 4)) ((0 1 2 3 4) (0 2 3 4) (0 3 4) (0 4)) CL-USER> (maplist #'append '(a b c d -) '(1 2 3)) ((A B C D - 1 2 3) (B C D - 2 3) (C D - 3))