(load "/home/rebelsky/Web/Courses/CS151/2007S/Examples/unit-test.scm")

(define reverse1
  (lambda (lst)
    (letrec ((kernel
              (lambda (remaining so-far)
                (if (null? remaining)
                    so-far
                    (kernel (cdr remaining)
                                    (cons (car remaining) so-far))))))
      (kernel lst null))))

(define reverse
  (lambda (lst)
    (let kernel
       ((remaining lst)
        (so-far null))
      (if (null? remaining)
          so-far
          (kernel (cdr remaining)
                  (cons (car remaining) so-far))))))



(begin-tests!)
(test! (reverse null) null)
(test! (reverse (list 1 2 3)) (list 3 2 1))
(test! (reverse (list 'a 'b 'c)) (list 'c 'b 'a))
(test-error! (reverse (cons 1 2)))
(end-tests!)