Re: When to use apply

Of course, after going through all of that you then see why loop is so
handy:
 
CL-USER> (defun nth-elements (n &rest lists)
           (loop for item in lists collect (nth n item)))
 
NTH-ELEMENTS
CL-USER> (nth-elements 3 '(10 20 hello x world) '(-1 -2 -3 y) '(z0 z1 z2 z))
 
(X Y Z)

>
(define (nth-elements n . seqs)
  (map (lambda (xs) (list-ref xs n)) seqs))
>
(nth-elements 3
  '(10 20 hello x world)
  '(-1 -2 -3 y)
  '(z0 z1 z2 z))