ow). Networking now allows I/O objects to construct with any instance
        of <a href="../../../../../../doc/html/boost_asio/reference/ExecutionContext.html" target="_top"><span class="emphasis"><em>ExecutionContext</em></span></a>
        or <a href="../../../../../../doc/html/boost_asio/reference/Executor1.html" target="_top"><span class="emphasis"><em>Executor</em></span></a>
        objects. Here we construct a stream which uses a particular I/O context to
        dispatch completion handlers:
      