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// Copyright 2015 Peter Dimov.
//
// 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
#if defined(_MSC_VER)
#pragma warning( disable: 4244 ) // 'initializing': conversion from 'int' to 'char', possible loss of data
#endif
#include <boost/mp11/tuple.hpp>
#include <boost/mp11/detail/config.hpp>
// Technically std::tuple isn't constexpr enabled in C++11, but it works with libstdc++
#if defined( BOOST_MP11_NO_CONSTEXPR ) || ( !defined(_MSC_VER) && !defined( __GLIBCXX__ ) && __cplusplus < 201400L )
int main() {}
#else
#include <tuple>
#include <array>
#include <utility>
struct T1
{
int x, y, z;
constexpr T1( int x = 0, int y = 0, int z = 0 ): x(x), y(y), z(z) {}
};
int main()
{
using boost::mp11::construct_from_tuple;
{
constexpr std::tuple<int, short, char> tp{ 1, 2, 3 };
constexpr auto r = construct_from_tuple<T1>( tp );
static_assert( r.x == 1, "r.x == 1" );
static_assert( r.y == 2, "r.y == 2" );
static_assert( r.z == 3, "r.z == 3" );
}
{
constexpr std::pair<short, char> tp{ 1, 2 };
constexpr auto r = construct_from_tuple<T1>( tp );
static_assert( r.x == 1, "r.x == 1" );
static_assert( r.y == 2, "r.y == 2" );
static_assert( r.z == 0, "r.z == 0" );
}
{
constexpr std::array<short, 3> tp{{ 1, 2, 3 }};
constexpr auto r = construct_from_tuple<T1>( tp );
static_assert( r.x == 1, "r.x == 1" );
static_assert( r.y == 2, "r.y == 2" );
static_assert( r.z == 3, "r.z == 3" );
}
#if defined( __clang_major__ ) && __clang_major__ == 3 && __clang_minor__ < 9
// "error: default initialization of an object of const type 'const std::tuple<>' without a user-provided default constructor"
#else
{
constexpr std::tuple<> tp;
constexpr auto r = construct_from_tuple<T1>( tp );
static_assert( r.x == 0, "r.x == 0" );
static_assert( r.y == 0, "r.y == 0" );
static_assert( r.z == 0, "r.z == 0" );
}
#endif
}
#endif
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