;;; $Id: product-mod.scm,v 1.2 2006/01/05 22:24:09 leavens Exp $

(module product-mod (lib "typedscm.ss" "typedscm")

(provide product product-from-list)

(deftype product (-> (number ...) number))
(define product
  (lambda args
    (product-from-list args)))

(deftype product-from-list (-> ((list-of number)) number))
(define product-from-list
  (lambda (prod-list)
    (if (null? prod-list)
        1
        (* (car prod-list)
           (product-from-list (cdr prod-list))))))

) ;; end module