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// UNSUPPORTED: c++98, c++03, c++11
11
12// <experimental/tuple>
13
14// template <class F, class T> constexpr decltype(auto) apply(F &&, T &&)
15
16// Testing ref qualified functions
17
18#include <experimental/tuple>
19#include <cassert>
20
21struct func_obj
22{
23    constexpr func_obj() {}
24
25    constexpr int operator()() const & { return 1; }
26    constexpr int operator()() const && { return 2; }
27    constexpr int operator()() & { return 3; }
28    constexpr int operator()() && { return 4; }
29};
30
31namespace ex = std::experimental;
32
33int main()
34{
35// TODO(ericwf): Re-enable constexpr support
36/*
37    {
38        constexpr func_obj f;
39        constexpr std::tuple<> tp;
40
41        static_assert(1 == ex::apply(static_cast<func_obj const &>(f), tp), "");
42        static_assert(2 == ex::apply(static_cast<func_obj const &&>(f), tp), "");
43    }
44*/
45    {
46        func_obj f;
47        std::tuple<> tp;
48        assert(1 == ex::apply(static_cast<func_obj const &>(f), tp));
49        assert(2 == ex::apply(static_cast<func_obj const &&>(f), tp));
50        assert(3 == ex::apply(static_cast<func_obj &>(f), tp));
51        assert(4 == ex::apply(static_cast<func_obj &&>(f), tp));
52    }
53}
54