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 <size_t I, class... Types>
14// typename tuple_element<I, tuple<Types...> >::type&
15// get(tuple<Types...>& t);
16
17// UNSUPPORTED: c++03
18
19#include <tuple>
20#include <string>
21#include <cassert>
22
23#include "test_macros.h"
24
25#if TEST_STD_VER > 11
26
27struct Empty {};
28
29struct S {
30 std::tuple<int, Empty> a;
31 int k;
32 Empty e;
33 constexpr S() : a{1,Empty{}}, k(std::get<0>(a)), e(std::get<1>(a)) {}
34 };
35
36constexpr std::tuple<int, int> getP () { return { 3, 4 }; }
37#endif
38
39int main(int, char**)
40{
41 {
42 typedef std::tuple<int> T;
43 T t(3);
44 assert(std::get<0>(t) == 3);
45 std::get<0>(t&: t) = 2;
46 assert(std::get<0>(t) == 2);
47 }
48 {
49 typedef std::tuple<std::string, int> T;
50 T t("high", 5);
51 assert(std::get<0>(t) == "high");
52 assert(std::get<1>(t) == 5);
53 std::get<0>(t&: t) = "four";
54 std::get<1>(t&: t) = 4;
55 assert(std::get<0>(t) == "four");
56 assert(std::get<1>(t) == 4);
57 }
58 {
59 typedef std::tuple<double&, std::string, int> T;
60 double d = 1.5;
61 T t(d, "high", 5);
62 assert(std::get<0>(t) == 1.5);
63 assert(std::get<1>(t) == "high");
64 assert(std::get<2>(t) == 5);
65 std::get<0>(t&: t) = 2.5;
66 std::get<1>(t&: t) = "four";
67 std::get<2>(t&: t) = 4;
68 assert(std::get<0>(t) == 2.5);
69 assert(std::get<1>(t) == "four");
70 assert(std::get<2>(t) == 4);
71 assert(d == 2.5);
72 }
73#if TEST_STD_VER > 11
74 { // get on an rvalue tuple
75 static_assert ( std::get<0> ( std::make_tuple ( 0.0f, 1, 2.0, 3L )) == 0, "" );
76 static_assert ( std::get<1> ( std::make_tuple ( 0.0f, 1, 2.0, 3L )) == 1, "" );
77 static_assert ( std::get<2> ( std::make_tuple ( 0.0f, 1, 2.0, 3L )) == 2, "" );
78 static_assert ( std::get<3> ( std::make_tuple ( 0.0f, 1, 2.0, 3L )) == 3, "" );
79 static_assert(S().k == 1, "");
80 static_assert(std::get<1>(getP()) == 4, "");
81 }
82#endif
83
84
85 return 0;
86}
87

source code of libcxx/test/std/utilities/tuple/tuple.tuple/tuple.elem/get_non_const.pass.cpp