#lang planet neil/sicp
(define a (list 1 2 3))(define (reverse lst)(iter lst '()))(define (iter reminder result)(if (null? reminder) result(iter (cdr reminder)(cons (car reminder) result))))
运行:
Welcome to DrRacket, version 5.3.3 [3m].
Language: planet neil/sicp; memory limit: 512 MB.
> (reverse a)
(mcons 3 (mcons 2 (mcons 1 '())))
>