test/libcxx/utilities/utility/pairs/pairs.pair/U_V.pass.cpp

//===----------------------------------------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//

// UNSUPPORTED: c++98, c++03

// <utility>

// template <class T1, class T2> struct pair

// template<class U, class V> pair(U&& x, V&& y);

#include <utility>

#include "test_macros.h"


struct ExplicitT {
    constexpr explicit ExplicitT(int x) : value(x) {}
    int value;
};

struct ImplicitT {
    constexpr ImplicitT(int x) : value(x) {}
    int value;
};

struct ExplicitNothrowT {
    explicit ExplicitNothrowT(int x) noexcept : value(x) {}
    int value;
};

struct ImplicitNothrowT {
    ImplicitNothrowT(int x) noexcept : value(x) {}
    int value;
};

int main(int, char**) {
    { // explicit noexcept test
        static_assert(!std::is_nothrow_constructible<std::pair<ExplicitT, ExplicitT>, int, int>::value, "");
        static_assert(!std::is_nothrow_constructible<std::pair<ExplicitNothrowT, ExplicitT>, int, int>::value, "");
        static_assert(!std::is_nothrow_constructible<std::pair<ExplicitT, ExplicitNothrowT>, int, int>::value, "");
        static_assert( std::is_nothrow_constructible<std::pair<ExplicitNothrowT, ExplicitNothrowT>, int, int>::value, "");
    }
    { // implicit noexcept test
        static_assert(!std::is_nothrow_constructible<std::pair<ImplicitT, ImplicitT>, int, int>::value, "");
        static_assert(!std::is_nothrow_constructible<std::pair<ImplicitNothrowT, ImplicitT>, int, int>::value, "");
        static_assert(!std::is_nothrow_constructible<std::pair<ImplicitT, ImplicitNothrowT>, int, int>::value, "");
        static_assert( std::is_nothrow_constructible<std::pair<ImplicitNothrowT, ImplicitNothrowT>, int, int>::value, "");
    }

  return 0;
}