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  26 <div class="titlepage"><div><div><h3 class="title">
  27 <a name="boost_asio.reference.use_awaitable_t"></a><a class="link" href="use_awaitable_t.html" title="use_awaitable_t">use_awaitable_t</a>
  28 </h3></div></div></div>
  29 <p>
  30         A completion token that represents the currently executing coroutine.
  31       </p>
  32 <pre class="programlisting">template&lt;
  33     typename <a class="link" href="Executor1.html" title="Executor requirements">Executor</a> = executor&gt;
  34 struct use_awaitable_t
  35 </pre>
  36 <h5>
  37 <a name="boost_asio.reference.use_awaitable_t.h0"></a>
  38         <span class="phrase"><a name="boost_asio.reference.use_awaitable_t.types"></a></span><a class="link" href="use_awaitable_t.html#boost_asio.reference.use_awaitable_t.types">Types</a>
  39       </h5>
  40 <div class="informaltable"><table class="table">
  41 <colgroup>
  42 <col>
  43 <col>
  44 </colgroup>
  45 <thead><tr>
  46 <th>
  47                 <p>
  48                   Name
  49                 </p>
  50               </th>
  51 <th>
  52                 <p>
  53                   Description
  54                 </p>
  55               </th>
  56 </tr></thead>
  57 <tbody><tr>
  58 <td>
  59                 <p>
  60                   <a class="link" href="use_awaitable_t__executor_with_default.html" title="use_awaitable_t::executor_with_default"><span class="bold"><strong>executor_with_default</strong></span></a>
  61                 </p>
  62               </td>
  63 <td>
  64                 <p>
  65                   Adapts an executor to add the use_awaitable_t completion token
  66                   as the default.
  67                 </p>
  68               </td>
  69 </tr></tbody>
  70 </table></div>
  71 <h5>
  72 <a name="boost_asio.reference.use_awaitable_t.h1"></a>
  73         <span class="phrase"><a name="boost_asio.reference.use_awaitable_t.member_functions"></a></span><a class="link" href="use_awaitable_t.html#boost_asio.reference.use_awaitable_t.member_functions">Member Functions</a>
  74       </h5>
  75 <div class="informaltable"><table class="table">
  76 <colgroup>
  77 <col>
  78 <col>
  79 </colgroup>
  80 <thead><tr>
  81 <th>
  82                 <p>
  83                   Name
  84                 </p>
  85               </th>
  86 <th>
  87                 <p>
  88                   Description
  89                 </p>
  90               </th>
  91 </tr></thead>
  92 <tbody>
  93 <tr>
  94 <td>
  95                 <p>
  96                   <a class="link" href="use_awaitable_t/as_default_on.html" title="use_awaitable_t::as_default_on"><span class="bold"><strong>as_default_on</strong></span></a>
  97                 </p>
  98               </td>
  99 <td>
 100                 <p>
 101                   Function helper to adapt an I/O object to use use_awaitable_t as
 102                   its default completion token type.
 103                 </p>
 104               </td>
 105 </tr>
 106 <tr>
 107 <td>
 108                 <p>
 109                   <a class="link" href="use_awaitable_t/use_awaitable_t.html" title="use_awaitable_t::use_awaitable_t"><span class="bold"><strong>use_awaitable_t</strong></span></a>
 110                 </p>
 111               </td>
 112 <td>
 113                 <p>
 114                   Default constructor.
 115                 </p>
 116               </td>
 117 </tr>
 118 </tbody>
 119 </table></div>
 120 <p>
 121         The <code class="computeroutput">use_awaitable_t</code> class, with its value <code class="computeroutput">use_awaitable</code>,
 122         is used to represent the currently executing coroutine. This completion token
 123         may be passed as a handler to an asynchronous operation. For example:
 124       </p>
 125 <pre class="programlisting">awaitable&lt;void&gt; my_coroutine()
 126 {
 127   std::size_t n = co_await my_socket.async_read_some(buffer, use_awaitable);
 128   ...
 129 }
 130 </pre>
 131 <p>
 132         When used with co_await, the initiating function (<code class="computeroutput">async_read_some</code>
 133         in the above example) suspends the current coroutine. The coroutine is resumed
 134         when the asynchronous operation completes, and the result of the operation
 135         is returned.
 136       </p>
 137 <h5>
 138 <a name="boost_asio.reference.use_awaitable_t.h2"></a>
 139         <span class="phrase"><a name="boost_asio.reference.use_awaitable_t.requirements"></a></span><a class="link" href="use_awaitable_t.html#boost_asio.reference.use_awaitable_t.requirements">Requirements</a>
 140       </h5>
 141 <p>
 142         <span class="emphasis"><em>Header: </em></span><code class="literal">boost/asio/use_awaitable.hpp</code>
 143       </p>
 144 <p>
 145         <span class="emphasis"><em>Convenience header: </em></span><code class="literal">boost/asio.hpp</code>
 146       </p>
 147 </div>
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 150 <td align="right"><div class="copyright-footer">Copyright &#169; 2003-2019 Christopher M. Kohlhoff<p>
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