scsh-0.6/scheme/alt/code-vector.scm

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1999-09-14 08:45:02 -04:00
; Copyright (c) 1993-1999 by Richard Kelsey and Jonathan Rees. See file COPYING.
; Code-vectors implemented as vectors.
(define *code-vector-marker* (list '*code-vector-marker*))
(define (make-code-vector len init)
(let ((t (make-vector (+ len 1) init)))
(vector-set! t 0 *code-vector-marker*)
t))
(define (code-vector? obj)
(and (vector? obj)
(> (vector-length obj) 0)
(eq? (vector-ref obj 0) *code-vector-marker*)))
(define (code-vector-length t) (- (vector-length t) 1))
(define (code-vector-ref t i) (vector-ref t (+ i 1)))
(define (code-vector-set! t i x) (vector-set! t (+ i 1) x))