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-exception
6//
7//===----------------------------------------------------------------------===//
8
9// <tuple>
10
11// template <class... Types> class tuple;
12
13// template<class... Types>
14// tuple<Types&...> tie(Types&... t);
15
16// UNSUPPORTED: c++03
17
18#include <tuple>
19#include <string>
20#include <cassert>
21
22#include "test_macros.h"
23
24TEST_CONSTEXPR_CXX14
25bool test_tie()
26{
27 {
28 int i = 42;
29 double f = 1.1;
30 using ExpectT = std::tuple<int&, decltype(std::ignore)&, double&>;
31 auto res = std::tie(i, std::ignore, f);
32 static_assert(std::is_same<ExpectT, decltype(res)>::value, "");
33 assert(&std::get<0>(res) == &i);
34 assert(&std::get<1>(res) == &std::ignore);
35 assert(&std::get<2>(res) == &f);
36
37#if TEST_STD_VER >= 20
38 res = std::make_tuple(101, nullptr, -1.0);
39 assert(i == 101);
40 assert(f == -1.0);
41#endif
42 }
43 return true;
44}
45
46int main(int, char**)
47{
48 test_tie();
49#if TEST_STD_VER >= 14
50 static_assert(test_tie(), "");
51#endif
52
53 {
54 int i = 0;
55 std::string s;
56 std::tie(args&: i, args: std::ignore, args&: s) = std::make_tuple(args: 42, args: 3.14, args: "C++");
57 assert(i == 42);
58 assert(s == "C++");
59 }
60
61 return 0;
62}
63

source code of libcxx/test/std/utilities/tuple/tuple.tuple/tuple.creation/tie.pass.cpp