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 // <utility>
11 
12 // template <class T1, class T2> struct pair
13 
14 // template <class... Args1, class... Args2>
15 //     pair(piecewise_construct_t, tuple<Args1...> first_args,
16 //                                 tuple<Args2...> second_args);
17 
18 #include <utility>
19 #include <tuple>
20 #include <cassert>
21 
main()22 int main()
23 {
24 #ifndef _LIBCPP_HAS_NO_VARIADICS
25     {
26         typedef std::pair<int, int*> P1;
27         typedef std::pair<int*, int> P2;
28         typedef std::pair<P1, P2> P3;
29         P3 p3(std::piecewise_construct, std::tuple<int, int*>(3, nullptr),
30                                         std::tuple<int*, int>(nullptr, 4));
31         assert(p3.first == P1(3, nullptr));
32         assert(p3.second == P2(nullptr, 4));
33     }
34 #endif  // _LIBCPP_HAS_NO_VARIADICS
35 }
36