36 lines
1.1 KiB
Racket
36 lines
1.1 KiB
Racket
#lang scribble/doc
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@(require "mz.ss")
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@title[#:tag "values"]{Multiple Values}
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See @secref["values-model"] for general information about multiple
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result values. In addition to @scheme[call-with-values] (described in
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this section), the @scheme[let-values], @scheme[let*-values],
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@scheme[letrec-values], and @scheme[define-values] forms (among
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others) create continuations that receive multiple values.
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@defproc[(values [v any/c] ...) any]{
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Returns the given @scheme[v]s. That is, @scheme[values] returns as
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provided arguments.
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@examples[
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(values 1)
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(values 1 2 3)
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(values)
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]}
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@defproc[(call-with-values [generator (-> any)] [receiver procedure?]) any]{
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Calls @scheme[generator], and passes the values that
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@scheme[generator] produces as arguments to @scheme[receiver]. Thus,
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@scheme[call-with-values] creates a continuation that accepts any
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number of values that @scheme[receiver] can accept. The
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@scheme[receiver] procedure is called in tail position with respect to
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the @scheme[call-with-values] call.
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@examples[
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(call-with-values (lambda () (values 1 2)) +)
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(call-with-values (lambda () 1) (lambda (x y) (+ x y)))
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]}
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