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; Part of Scheme 48 1.9. See file COPYING for notices and license.
; Authors: Richard Kelsey, Jonathan Rees
; Multiple return values
(define multiple-value-token (vector 'multiple-value-token))
(define (values . things)
(if (and (pair? things)
(null? (cdr things)))
(car things)
(cons multiple-value-token things)))
(define (call-with-values producer consumer)
(let ((things (producer)))
(if (and (pair? things)
(eq? (car things) multiple-value-token))
(apply consumer (cdr things))
(consumer things))))
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