boost/mysql/underlying_row.hpp

0001 //
0002 // Copyright (c) 2019-2024 Ruben Perez Hidalgo (rubenperez038 at gmail dot com)
0003 //
0004 // Distributed under the Boost Software License, Version 1.0. (See accompanying
0005 // file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
0006 //
0007
0008 #ifndef BOOST_MYSQL_UNDERLYING_ROW_HPP
0009 #define BOOST_MYSQL_UNDERLYING_ROW_HPP
0010
0011 #include <boost/mysql/detail/typing/row_traits.hpp>
0012
0013 #ifdef BOOST_MYSQL_CXX14
0014
0015 namespace boost {
0016 namespace mysql {
0017
0018 /**
0019  * \brief Type trait to retrieve the underlying row type.
0020  * \details
0021  * Given an input type `T` satisfying the `StaticRow` concept,
0022  * this trait is an alias for its underlying row type. It is defined as follows:
0023  * \n
0024  * \li If `T` is a marker type, like \ref pfr_by_name "pfr_by_name<U>", `underlying_row_t`
0025  *     is an alias for the marker's inner type `U`.
0026  * \li If `T` is not a marker type (e.g. it's a Boost.Describe struct or a `std::tuple`),
0027  *     `underlying_row_t` is an alias for `T`.
0028  *
0029  * For instance, \ref static_results::rows uses this trait to determine its return type.
0030  */
0031 template <BOOST_MYSQL_STATIC_ROW StaticRow>
0032 using underlying_row_t =
0033 #ifdef BOOST_MYSQL_DOXYGEN
0034     __see_below__
0035 #else
0036     detail::underlying_row_t<StaticRow>
0037 #endif
0038     ;
0039
0040 }  // namespace mysql
0041 }  // namespace boost
0042
0043 #endif
0044
0045 #endif