yao2030 · December 12, 2012 07:04 · yao2030 · Dec 12, 2012
diff --git a/map.scm b/map.scm
 (define (map p sequence)
 	(accumulate (lambda (x y) (cons (p x) y)) '() sequence))
 (define (append seq1 seq2)
  (accumulate cons seq2 seq1))
 ;; it took me about half an hour to figure length out.
 (define (length sequence)
 	(accumulate (lambda (x y) (+ 1 y)) 0 sequence))
	(define (map p sequence)
	(accumulate (lambda (x y) (cons (p x) y)) '() sequence))
	(define (append seq1 seq2)
	(accumulate cons seq2 seq1))
	;; it took me about half an hour to figure length out.
	(define (length sequence)
	(accumulate (lambda (x y) (+ 1 y)) 0 sequence))