chickadee » scheme » base » vector-for-each

It is an error if proc does not accept as many arguments as there are vectors. The arguments to vector-for-each are like the arguments to vector-map, but vector-for-each calls proc for its side effects rather than for its values. Unlike vector-map, vector-for-each is guaranteed to call proc on the elements of the vectors in order from the first element(s) to the last, and the value returned by vector-for-each is unspecified. If more than one vector is given and not all vectors have the same length, vector-for-each terminates when the shortest vector runs out. It is an error for proc to mutate any of the vectors.

(let ((v (make-list 5)))
  (vector-for-each
   (lambda (i) (list-set! v i (* i i)))
   '#(0 1 2 3 4))
  v)                                 ==>  (0 1 4 9 16)