20 lines
514 B
Scheme
20 lines
514 B
Scheme
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; Copyright (c) 1993-1999 by Richard Kelsey and Jonathan Rees. See file COPYING.
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; Multiple return values
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(define multiple-value-token (vector 'multiple-value-token))
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(define (values . things)
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(if (and (pair? things)
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(null? (cdr things)))
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(car things)
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(cons multiple-value-token things)))
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(define (call-with-values producer consumer)
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(let ((things (producer)))
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(if (and (pair? things)
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(eq? (car things) multiple-value-token))
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(apply consumer (cdr things))
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(consumer things))))
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