tuple_element.pass.cpp revision 50fe0c7d61131dd693fce234573e30441eb35b38 
1//===----------------------------------------------------------------------===//
2//
3//                     The LLVM Compiler Infrastructure
4//
5// This file is dual licensed under the MIT and the University of Illinois Open
6// Source Licenses. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9
10// <tuple>
11
12// template <class... Types> class tuple;
13
14// template <size_t I, class... Types>
15// class tuple_element<I, tuple<Types...> >
16// {
17// public:
18//     typedef Ti type;
19// };
20
21#include <tuple>
22#include <type_traits>
23
24template <class T, std::size_t N, class U>
25void test()
26{
27    static_assert((std::is_same<typename std::tuple_element<N, T>::type, U>::value), "");
28    static_assert((std::is_same<typename std::tuple_element<N, const T>::type, const U>::value), "");
29    static_assert((std::is_same<typename std::tuple_element<N, volatile T>::type, volatile U>::value), "");
30    static_assert((std::is_same<typename std::tuple_element<N, const volatile T>::type, const volatile U>::value), "");
31#if _LIBCPP_STD_VER > 11
32    static_assert((std::is_same<typename std::tuple_element_t<N, T>, U>::value), "");
33    static_assert((std::is_same<typename std::tuple_element_t<N, const T>, const U>::value), "");
34    static_assert((std::is_same<typename std::tuple_element_t<N, volatile T>, volatile U>::value), "");
35    static_assert((std::is_same<typename std::tuple_element_t<N, const volatile T>, const volatile U>::value), "");
36#endif
37}
38
39int main()
40{
41    test<std::tuple<int>, 0, int>();
42    test<std::tuple<char, int>, 0, char>();
43    test<std::tuple<char, int>, 1, int>();
44    test<std::tuple<int*, char, int>, 0, int*>();
45    test<std::tuple<int*, char, int>, 1, char>();
46    test<std::tuple<int*, char, int>, 2, int>();
47}
48