55 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// LWG #2212 says that tuple_size and tuple_element must be20// available after including <utility>21 22#include <array>23#include <type_traits>24 25#include "test_macros.h"26 27template <class T, std::size_t N, class U, std::size_t idx>28void test()29{30 static_assert((std::is_base_of<std::integral_constant<std::size_t, N>,31 std::tuple_size<T> >::value), "");32 static_assert((std::is_base_of<std::integral_constant<std::size_t, N>,33 std::tuple_size<const T> >::value), "");34 static_assert((std::is_base_of<std::integral_constant<std::size_t, N>,35 std::tuple_size<volatile T> >::value), "");36 static_assert((std::is_base_of<std::integral_constant<std::size_t, N>,37 std::tuple_size<const volatile T> >::value), "");38 static_assert((std::is_same<typename std::tuple_element<idx, T>::type, U>::value), "");39 static_assert((std::is_same<typename std::tuple_element<idx, const T>::type, const U>::value), "");40 static_assert((std::is_same<typename std::tuple_element<idx, volatile T>::type, volatile U>::value), "");41 static_assert((std::is_same<typename std::tuple_element<idx, const volatile T>::type, const volatile U>::value), "");42}43 44int main(int, char**)45{46 test<std::array<int, 5>, 5, int, 0>();47 test<std::array<int, 5>, 5, int, 1>();48 test<std::array<const char *, 4>, 4, const char *, 3>();49 test<std::array<volatile int, 4>, 4, volatile int, 3>();50 test<std::array<char *, 3>, 3, char *, 1>();51 test<std::array<char *, 3>, 3, char *, 2>();52 53 return 0;54}55