scsh-0.6/ps-compiler/prescheme/test/record.scm

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1999-09-14 08:45:02 -04:00
; Copyright (c) 1994 by Richard Kelsey. See file COPYING.
(define-data-type list
(pair? (cons car cdr)
(car integer car set-car!)
(cdr list cdr set-cdr!))
(null? null))
(define (member? list x)
(let loop ((list list))
(cond ((null? list)
#f)
((= x (car list))
#t)
(else
(loop (cdr list))))))
(define (reverse! list)
(if (or (null? list)
(null? (cdr list)))
list
(let loop ((list list) (prev null))
(let ((next (cdr list)))
(set-cdr! list prev)
(if (null? next)
list
(loop next list))))))