boost/asio/placeholders.hpp

0001 //
0002 // placeholders.hpp
0003 // ~~~~~~~~~~~~~~~~
0004 //
0005 // Copyright (c) 2003-2023 Christopher M. Kohlhoff (chris at kohlhoff dot com)
0006 //
0007 // Distributed under the Boost Software License, Version 1.0. (See accompanying
0008 // file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
0009 //
0010
0011 #ifndef BOOST_ASIO_PLACEHOLDERS_HPP
0012 #define BOOST_ASIO_PLACEHOLDERS_HPP
0013
0014 #if defined(_MSC_VER) && (_MSC_VER >= 1200)
0015 # pragma once
0016 #endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
0017
0018 #include <boost/asio/detail/config.hpp>
0019 #include <boost/asio/detail/functional.hpp>
0020
0021 #include <boost/asio/detail/push_options.hpp>
0022
0023 namespace boost {
0024 namespace asio {
0025 namespace placeholders {
0026
0027 #if defined(GENERATING_DOCUMENTATION)
0028
0029 /// An argument placeholder, for use with std::bind() or boost::bind(), that
0030 /// corresponds to the error argument of a handler for any of the asynchronous
0031 /// functions.
0032 unspecified error;
0033
0034 /// An argument placeholder, for use with std::bind() or boost::bind(), that
0035 /// corresponds to the bytes_transferred argument of a handler for asynchronous
0036 /// functions such as boost::asio::basic_stream_socket::async_write_some or
0037 /// boost::asio::async_write.
0038 unspecified bytes_transferred;
0039
0040 /// An argument placeholder, for use with std::bind() or boost::bind(), that
0041 /// corresponds to the iterator argument of a handler for asynchronous functions
0042 /// such as boost::asio::async_connect.
0043 unspecified iterator;
0044
0045 /// An argument placeholder, for use with std::bind() or boost::bind(), that
0046 /// corresponds to the results argument of a handler for asynchronous functions
0047 /// such as boost::asio::basic_resolver::async_resolve.
0048 unspecified results;
0049
0050 /// An argument placeholder, for use with std::bind() or boost::bind(), that
0051 /// corresponds to the results argument of a handler for asynchronous functions
0052 /// such as boost::asio::async_connect.
0053 unspecified endpoint;
0054
0055 /// An argument placeholder, for use with std::bind() or boost::bind(), that
0056 /// corresponds to the signal_number argument of a handler for asynchronous
0057 /// functions such as boost::asio::signal_set::async_wait.
0058 unspecified signal_number;
0059
0060 #else
0061
0062 static constexpr auto& error = std::placeholders::_1;
0063 static constexpr auto& bytes_transferred = std::placeholders::_2;
0064 static constexpr auto& iterator = std::placeholders::_2;
0065 static constexpr auto& results = std::placeholders::_2;
0066 static constexpr auto& endpoint = std::placeholders::_2;
0067 static constexpr auto& signal_number = std::placeholders::_2;
0068
0069 #endif
0070
0071 } // namespace placeholders
0072 } // namespace asio
0073 } // namespace boost
0074
0075 #include <boost/asio/detail/pop_options.hpp>
0076
0077 #endif // BOOST_ASIO_PLACEHOLDERS_HPP