An Establisher is used by internal::AsioEndpoint to create and connect a Boost.Asio socket.

Given

est: an Establisher instance
handler: a callable entity with the signature:

void (boost::system::error_code, Establisher::SocketPtr&&)

then:

Establisher must be move-constrictible, and,
the following expressions must be valid:

Expression	Effect
`Establisher::Socket`	Yields the type of socket that the Establisher creates and connects.
`Establisher::SocketPtr`	Yields a shared pointer type to an Establisher::Socket.
`est.establish(handler)`	Establishes the socket connection, then calls `handler`.
`est.cancel()`	Cancels an `establish` operation in progress.

If an establish operation is cancelled, it shall return, via the completion handler, an error code equivalent to boost::system::errc::operation_canceled.

The following classes meet the requirements of Establisher:

wamp::internal::TcpAcceptor
wamp::internal::TcpOpener
wamp::internal::UdsAcceptor
wamp::internal::UdsOpener