1<html> 2<head> 3<meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> 4<title>associated_allocator</title> 5<link rel="stylesheet" href="../../../../doc/src/boostbook.css" type="text/css"> 6<meta name="generator" content="DocBook XSL Stylesheets V1.79.1"> 7<link rel="home" href="../../boost_asio.html" title="Boost.Asio"> 8<link rel="up" href="../reference.html" title="Reference"> 9<link rel="prev" href="asio_handler_is_continuation.html" title="asio_handler_is_continuation"> 10<link rel="next" href="associated_allocator/get.html" title="associated_allocator::get"> 11</head> 12<body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"> 13<table cellpadding="2" width="100%"><tr> 14<td valign="top"><img alt="Boost C++ Libraries" width="277" height="86" src="../../../../boost.png"></td> 15<td align="center"><a href="../../../../index.html">Home</a></td> 16<td align="center"><a href="../../../../libs/libraries.htm">Libraries</a></td> 17<td align="center"><a href="http://www.boost.org/users/people.html">People</a></td> 18<td align="center"><a href="http://www.boost.org/users/faq.html">FAQ</a></td> 19<td align="center"><a href="../../../../more/index.htm">More</a></td> 20</tr></table> 21<hr> 22<div class="spirit-nav"> 23<a accesskey="p" href="asio_handler_is_continuation.html"><img src="../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../reference.html"><img src="../../../../doc/src/images/up.png" alt="Up"></a><a accesskey="h" href="../../boost_asio.html"><img src="../../../../doc/src/images/home.png" alt="Home"></a><a accesskey="n" href="associated_allocator/get.html"><img src="../../../../doc/src/images/next.png" alt="Next"></a> 24</div> 25<div class="section"> 26<div class="titlepage"><div><div><h3 class="title"> 27<a name="boost_asio.reference.associated_allocator"></a><a class="link" href="associated_allocator.html" title="associated_allocator">associated_allocator</a> 28</h3></div></div></div> 29<p> 30 Traits type used to obtain the allocator associated with an object. 31 </p> 32<pre class="programlisting">template< 33 typename T, 34 typename Allocator = std::allocator<void>> 35struct associated_allocator 36</pre> 37<h5> 38<a name="boost_asio.reference.associated_allocator.h0"></a> 39 <span class="phrase"><a name="boost_asio.reference.associated_allocator.types"></a></span><a class="link" href="associated_allocator.html#boost_asio.reference.associated_allocator.types">Types</a> 40 </h5> 41<div class="informaltable"><table class="table"> 42<colgroup> 43<col> 44<col> 45</colgroup> 46<thead><tr> 47<th> 48 <p> 49 Name 50 </p> 51 </th> 52<th> 53 <p> 54 Description 55 </p> 56 </th> 57</tr></thead> 58<tbody><tr> 59<td> 60 <p> 61 <a class="link" href="associated_allocator/type.html" title="associated_allocator::type"><span class="bold"><strong>type</strong></span></a> 62 </p> 63 </td> 64<td> 65 <p> 66 If T has a nested type allocator_type, T::allocator_type. Otherwise 67 Allocator. 68 </p> 69 </td> 70</tr></tbody> 71</table></div> 72<h5> 73<a name="boost_asio.reference.associated_allocator.h1"></a> 74 <span class="phrase"><a name="boost_asio.reference.associated_allocator.member_functions"></a></span><a class="link" href="associated_allocator.html#boost_asio.reference.associated_allocator.member_functions">Member 75 Functions</a> 76 </h5> 77<div class="informaltable"><table class="table"> 78<colgroup> 79<col> 80<col> 81</colgroup> 82<thead><tr> 83<th> 84 <p> 85 Name 86 </p> 87 </th> 88<th> 89 <p> 90 Description 91 </p> 92 </th> 93</tr></thead> 94<tbody><tr> 95<td> 96 <p> 97 <a class="link" href="associated_allocator/get.html" title="associated_allocator::get"><span class="bold"><strong>get</strong></span></a> <span class="silver">[static]</span> 98 </p> 99 </td> 100<td> 101 <p> 102 If T has a nested type allocator_type, returns t.get_allocator(). 103 Otherwise returns a. 104 </p> 105 </td> 106</tr></tbody> 107</table></div> 108<p> 109 A program may specialise this traits type if the <code class="computeroutput">T</code> template 110 parameter in the specialisation is a user-defined type. The template parameter 111 <code class="computeroutput">Allocator</code> shall be a type meeting the Allocator requirements. 112 </p> 113<p> 114 Specialisations shall meet the following requirements, where <code class="computeroutput">t</code> 115 is a const reference to an object of type <code class="computeroutput">T</code>, and <code class="computeroutput">a</code> 116 is an object of type <code class="computeroutput">Allocator</code>. 117 </p> 118<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "> 119<li class="listitem"> 120 Provide a nested typedef <code class="computeroutput">type</code> that identifies a type meeting 121 the Allocator requirements. 122 </li> 123<li class="listitem"> 124 Provide a noexcept static member function named <code class="computeroutput">get</code>, callable 125 as <code class="computeroutput">get(t)</code> and with return type <code class="computeroutput">type</code>. 126 </li> 127<li class="listitem"> 128 Provide a noexcept static member function named <code class="computeroutput">get</code>, callable 129 as <code class="computeroutput">get(t,a)</code> and with return type <code class="computeroutput">type</code>. 130 </li> 131</ul></div> 132<h5> 133<a name="boost_asio.reference.associated_allocator.h2"></a> 134 <span class="phrase"><a name="boost_asio.reference.associated_allocator.requirements"></a></span><a class="link" href="associated_allocator.html#boost_asio.reference.associated_allocator.requirements">Requirements</a> 135 </h5> 136<p> 137 <span class="emphasis"><em>Header: </em></span><code class="literal">boost/asio/associated_allocator.hpp</code> 138 </p> 139<p> 140 <span class="emphasis"><em>Convenience header: </em></span><code class="literal">boost/asio.hpp</code> 141 </p> 142</div> 143<table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr> 144<td align="left"></td> 145<td align="right"><div class="copyright-footer">Copyright © 2003-2020 Christopher M. 146 Kohlhoff<p> 147 Distributed under the Boost Software License, Version 1.0. (See accompanying 148 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>) 149 </p> 150</div></td> 151</tr></table> 152<hr> 153<div class="spirit-nav"> 154<a accesskey="p" href="asio_handler_is_continuation.html"><img src="../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../reference.html"><img src="../../../../doc/src/images/up.png" alt="Up"></a><a accesskey="h" href="../../boost_asio.html"><img src="../../../../doc/src/images/home.png" alt="Home"></a><a accesskey="n" href="associated_allocator/get.html"><img src="../../../../doc/src/images/next.png" alt="Next"></a> 155</div> 156</body> 157</html> 158
