Insane_DNS/libraries/asio-1.28.1/doc/asio/reference/can_require_concept.html

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<p>
<a class="indexterm" name="asio.indexterm.can_require_concept"></a>
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<p>
A type trait that determines whether a <code class="computeroutput"><span class="identifier">require_concept</span></code>
expression is well-formed.
</p>
<pre class="programlisting"><span class="keyword">template</span><span class="special">&lt;</span>
<span class="keyword">typename</span> <span class="identifier">T</span><span class="special">,</span>
<span class="keyword">typename</span> <span class="identifier">Property</span><span class="special">&gt;</span>
<span class="keyword">struct</span> <span class="identifier">can_require_concept</span>
</pre>
<p>
Class template <code class="computeroutput"><span class="identifier">can_require_concept</span></code>
is a trait that is derived from <code class="computeroutput"><span class="identifier">true_type</span></code>
if the expression <code class="computeroutput"><span class="identifier">asio</span><span class="special">::</span><span class="identifier">require_concept</span><span class="special">(</span><span class="identifier">std</span><span class="special">::</span><span class="identifier">declval</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&gt;(),</span>
<span class="identifier">std</span><span class="special">::</span><span class="identifier">declval</span><span class="special">&lt;</span><span class="identifier">Property</span><span class="special">&gt;())</span></code>
is well formed; otherwise <code class="computeroutput"><span class="identifier">false_type</span></code>.
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<span><a name="asio.reference.can_require_concept.requirements"></a></span><a class="link" href="can_require_concept.html#asio.reference.can_require_concept.requirements">Requirements</a>
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<p>
<span class="emphasis"><em>Header: </em></span><code class="literal">asio/require_concept.hpp</code>
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<p>
<span class="emphasis"><em>Convenience header: </em></span><code class="literal">asio.hpp</code>
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<div class="copyright-footer">Copyright © 2003-2023 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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