52 lines · cpp
1//===----------------------------------------------------------------------===//2//3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.4// See https://llvm.org/LICENSE.txt for license information.5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception6//7//===----------------------------------------------------------------------===//8 9// <tuple>10 11// template <class... Types> class tuple;12 13// template <size_t I, class... Types>14// struct tuple_element<I, tuple<Types...> >15// {16// typedef Ti type;17// };18 19// UNSUPPORTED: c++0320 21#include <tuple>22#include <type_traits>23 24#include "test_macros.h"25 26template <class T, std::size_t N, class U>27void test()28{29 static_assert((std::is_same<typename std::tuple_element<N, T>::type, U>::value), "");30 static_assert((std::is_same<typename std::tuple_element<N, const T>::type, const U>::value), "");31 static_assert((std::is_same<typename std::tuple_element<N, volatile T>::type, volatile U>::value), "");32 static_assert((std::is_same<typename std::tuple_element<N, const volatile T>::type, const volatile U>::value), "");33#if TEST_STD_VER > 1134 static_assert((std::is_same<typename std::tuple_element_t<N, T>, U>::value), "");35 static_assert((std::is_same<typename std::tuple_element_t<N, const T>, const U>::value), "");36 static_assert((std::is_same<typename std::tuple_element_t<N, volatile T>, volatile U>::value), "");37 static_assert((std::is_same<typename std::tuple_element_t<N, const volatile T>, const volatile U>::value), "");38#endif39}40 41int main(int, char**)42{43 test<std::tuple<int>, 0, int>();44 test<std::tuple<char, int>, 0, char>();45 test<std::tuple<char, int>, 1, int>();46 test<std::tuple<int*, char, int>, 0, int*>();47 test<std::tuple<int*, char, int>, 1, char>();48 test<std::tuple<int*, char, int>, 2, int>();49 50 return 0;51}52