...one of the most highly
regarded and expertly designed C++ library projects in the
world.
— Herb Sutter and Andrei
Alexandrescu, C++
Coding Standards
A composed connect handler must meet the requirements for a handler.
A value h
of a composed connect
handler class should work correctly in the expression h(ec,
i)
,
where ec
is an lvalue of
type const error_code
and i
is an lvalue of the
type Iterator
used in the
corresponding connect()
or async_connect()` function.
A free function as a composed connect handler:
void connect_handler( const boost::system::error_code& ec, boost::asio::ip::tcp::resolver::iterator iterator) { ... }
A composed connect handler function object:
struct connect_handler { ... template <typename Iterator> void operator()( const boost::system::error_code& ec, Iterator iterator) { ... } ... };
A non-static class member function adapted to a composed connect handler
using bind()
:
void my_class::connect_handler( const boost::system::error_code& ec, boost::asio::ip::tcp::resolver::iterator iterator) { ... } ... boost::asio::async_connect(..., boost::bind(&my_class::connect_handler, this, boost::asio::placeholders::error, boost::asio::placeholders::iterator));