Sender.html
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<div class="titlepage"><div><div><h3 class="title">
<a name="asio.reference.Sender"></a><a class="link" href="Sender.html" title="Sender concepts">Sender concepts</a>
</h3></div></div></div>
<h5>
<a name="asio.reference.Sender.h0"></a>
<span><a name="asio.reference.Sender.sender_and_sender_to"></a></span><a class="link" href="Sender.html#asio.reference.Sender.sender_and_sender_to">sender
and sender_to</a>
</h5>
<pre class="programlisting">template<class S>
concept sender =
move_constructible<remove_cvref_t<S>> &&
!requires {
typename sender_traits<remove_cvref_t<S>>::__unspecialized; // exposition only
};
template<class S, class R>
concept sender_to =
sender<S> &&
receiver<R> &&
requires (S&& s, R&& r) {
execution::connect((S&&) s, (R&&) r);
};
</pre>
<p>
None of these operations shall introduce data races as a result of concurrent
invocations of those functions from different threads.
</p>
<p>
A sender type's destructor shall not block pending completion of the submitted
function objects.
</p>
<p>
[<span class="emphasis"><em>Note:</em></span> The ability to wait for completion of submitted
function objects may be provided by the associated execution context. —<span class="emphasis"><em>end
note</em></span>]
</p>
<h5>
<a name="asio.reference.Sender.h1"></a>
<span><a name="asio.reference.Sender.typed_sender"></a></span><a class="link" href="Sender.html#asio.reference.Sender.typed_sender">typed_sender</a>
</h5>
<p>
A sender is <span class="bold"><strong>typed</strong></span> if it declares what types
it sends through a receiver's channels. The <code class="computeroutput">typed_sender</code> concept
is defined as:
</p>
<pre class="programlisting">template<template<template<class...> class Tuple, template<class...> class Variant> class>
struct has-value-types; // exposition only
template<template<class...> class Variant>
struct has-error-types; // exposition only
template<class S>
concept has-sender-types = // exposition only
requires {
typename has-value-types<S::template value_types>;
typename has-error-types<S::template error_types>;
typename bool_constant<S::sends_done>;
};
template<class S>
concept typed_sender =
sender<S> &&
has-sender-types<sender_traits<remove_cvref_t<S>>>;
</pre>
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<td align="right"><div class="copyright-footer">Copyright © 2003-2020 Christopher M.
Kohlhoff<p>
Distributed under the Boost Software License, Version 1.0. (See accompanying
file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
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