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[/
/ Copyright (c) 2003-2020 Christopher M. Kohlhoff (chris at kohlhoff dot com)
/
/ Distributed under the Boost Software License, Version 1.0. (See accompanying
/ file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
/]
[section:IteratorConnectHandler Iterator connect handler requirements]
An iterator connect handler must meet the requirements for a [link
boost_asio.reference.Handler handler]. A value `h` of an iterator 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.
[heading Examples]
A free function as an iterator connect handler:
void connect_handler(
const boost::system::error_code& ec,
boost::asio::ip::tcp::resolver::iterator iterator)
{
...
}
An iterator connect handler function object:
struct connect_handler
{
...
template <typename Iterator>
void operator()(
const boost::system::error_code& ec,
Iterator iterator)
{
...
}
...
};
A lambda as an iterator connect handler:
boost::asio::async_connect(...,
[](const boost::system::error_code& ec,
boost::asio::ip::tcp::resolver::iterator iterator)
{
...
});
A non-static class member function adapted to an iterator connect handler using
`std::bind()`:
void my_class::connect_handler(
const boost::system::error_code& ec,
boost::asio::ip::tcp::resolver::iterator iterator)
{
...
}
...
boost::asio::async_connect(...,
std::bind(&my_class::connect_handler,
this, std::placeholders::_1,
std::placeholders::_2));
A non-static class member function adapted to an iterator connect handler using
`boost::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));
[endsect]
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