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 // constexpr tuple();
15
16 // UNSUPPORTED: c++98, c++03
17
18 #include <tuple>
19 #include <string>
20 #include <cassert>
21 #include <type_traits>
22
23 #include "DefaultOnly.h"
24
25 struct NoDefault {
26 NoDefault() = delete;
NoDefaultNoDefault27 explicit NoDefault(int) { }
28 };
29
30 struct NoExceptDefault {
31 NoExceptDefault() noexcept = default;
32 };
33
34 struct ThrowingDefault {
ThrowingDefaultThrowingDefault35 ThrowingDefault() { }
36 };
37
38 struct IllFormedDefault {
IllFormedDefaultIllFormedDefault39 IllFormedDefault(int x) : value(x) {}
40 template <bool Pred = false>
IllFormedDefaultIllFormedDefault41 constexpr IllFormedDefault() {
42 static_assert(Pred,
43 "The default constructor should not be instantiated");
44 }
45 int value;
46 };
47
main()48 int main()
49 {
50 {
51 std::tuple<> t;
52 }
53 {
54 std::tuple<int> t;
55 assert(std::get<0>(t) == 0);
56 }
57 {
58 std::tuple<int, char*> t;
59 assert(std::get<0>(t) == 0);
60 assert(std::get<1>(t) == nullptr);
61 }
62 {
63 std::tuple<int, char*, std::string> t;
64 assert(std::get<0>(t) == 0);
65 assert(std::get<1>(t) == nullptr);
66 assert(std::get<2>(t) == "");
67 }
68 {
69 std::tuple<int, char*, std::string, DefaultOnly> t;
70 assert(std::get<0>(t) == 0);
71 assert(std::get<1>(t) == nullptr);
72 assert(std::get<2>(t) == "");
73 assert(std::get<3>(t) == DefaultOnly());
74 }
75 {
76 // See bug #21157.
77 static_assert(!std::is_default_constructible<std::tuple<NoDefault>>(), "");
78 static_assert(!std::is_default_constructible<std::tuple<DefaultOnly, NoDefault>>(), "");
79 static_assert(!std::is_default_constructible<std::tuple<NoDefault, DefaultOnly, NoDefault>>(), "");
80 }
81 {
82 static_assert(noexcept(std::tuple<NoExceptDefault>()), "");
83 static_assert(noexcept(std::tuple<NoExceptDefault, NoExceptDefault>()), "");
84
85 static_assert(!noexcept(std::tuple<ThrowingDefault, NoExceptDefault>()), "");
86 static_assert(!noexcept(std::tuple<NoExceptDefault, ThrowingDefault>()), "");
87 static_assert(!noexcept(std::tuple<ThrowingDefault, ThrowingDefault>()), "");
88 }
89 #ifndef _LIBCPP_HAS_NO_CONSTEXPR
90 {
91 constexpr std::tuple<> t;
92 }
93 {
94 constexpr std::tuple<int> t;
95 assert(std::get<0>(t) == 0);
96 }
97 {
98 constexpr std::tuple<int, char*> t;
99 assert(std::get<0>(t) == 0);
100 assert(std::get<1>(t) == nullptr);
101 }
102 {
103 // Check that the SFINAE on the default constructor is not evaluated when
104 // it isn't needed. If the default constructor is evaluated then this test
105 // should fail to compile.
106 IllFormedDefault v(0);
107 std::tuple<IllFormedDefault> t(v);
108 }
109 #endif
110 }
111