57 lines
1.8 KiB
Racket
57 lines
1.8 KiB
Racket
#lang scribble/doc
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@(require "mz.ss"
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(for-label scheme/async-channel))
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@title[#:tag "async-channel"]{Buffered Asynchronous Channels}
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@note-lib-only[scheme/async-channel]
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@margin-note/ref{See also @secref["threadmbox"].}
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@defproc[(async-channel? [v any/c]) boolean?]{
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Returns @scheme[#t] if @scheme[v] is an asynchronous channel,
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@scheme[#f] otherwise.}
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@defproc[(make-async-channel [limit (or/c exact-positive-integer? false/c) #f])
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async-channel?]{
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Returns an asynchronous channel with a buffer limit of @scheme[limit]
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items. A get operation blocks when the channel is empty, and a put
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operation blocks when the channel has @scheme[limit] items already.
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If @scheme[limit] is @scheme[#f], the channel buffer has no limit (so
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a put never blocks).
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The asynchronous channel value can be used directly with
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@scheme[sync]. The channel blocks until @scheme[async-channel-get]
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would return a value, and the unblock result is the received value.}
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@defproc[(async-channel-get [ach async-channel?]) any/c]{
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Blocks until at least one value is available in @scheme[ach], and then
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returns the first of the values that were put into
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@scheme[async-channel].}
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@defproc[(async-channel-try-get [ach async-channel?]) any/c]{
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If at least one value is immediately available in @scheme[ach],
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returns the first of the values that were put into @scheme[ach]. If
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@scheme[async-channel] is empty, the result is @scheme[#f].}
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@defproc[(async-channel-put [ach async-channel?][v any/c]) void?]{
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Puts @scheme[v] into @scheme[ach], blocking if @scheme[ach]'s buffer
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is full until space is available.}
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@defproc[(async-channel-put-evt [async-channel channel?][v any/c])
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evt?]{
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Returns a @tech{synchronizable event} that is blocked while
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@scheme[(async-channel-put ach v)] would block. The unblock result is
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the event itself. See also @scheme[sync].}
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