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 // UNSUPPORTED: c++98, c++03 22 23 #include <tuple> 24 #include <type_traits> 25 26 template <class T, std::size_t N, class U> 27 void 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 _LIBCPP_STD_VER > 11 34 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 #endif 39 } 40 41 int main() 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
