1// Copyright Louis Dionne 2013-2022
2// Distributed under the Boost Software License, Version 1.0.
3// (See accompanying file LICENSE.md or copy at http://boost.org/LICENSE_1_0.txt)
4
5#include <boost/hana/assert.hpp>
6#include <boost/hana/tuple.hpp>
7
8#include <type_traits>
9namespace hana = boost::hana;
10
11
12struct MoveOnly {
13 int data_;
14 MoveOnly(MoveOnly const&) = delete;
15 MoveOnly& operator=(MoveOnly const&) = delete;
16 MoveOnly(int data = 1) : data_(data) { }
17 MoveOnly(MoveOnly&& x) : data_(x.data_) { x.data_ = 0; }
18
19 MoveOnly& operator=(MoveOnly&& x)
20 { data_ = x.data_; x.data_ = 0; return *this; }
21
22 int get() const {return data_;}
23 bool operator==(const MoveOnly& x) const { return data_ == x.data_; }
24 bool operator< (const MoveOnly& x) const { return data_ < x.data_; }
25};
26
27struct Empty { };
28struct A {
29 int id_;
30 explicit constexpr A(int i) : id_(i) {}
31};
32
33struct NoDefault { NoDefault() = delete; };
34
35int main() {
36 {
37 hana::tuple<MoveOnly> t(MoveOnly(0));
38 BOOST_HANA_RUNTIME_CHECK(hana::at_c<0>(t) == 0);
39 }
40 {
41 hana::tuple<MoveOnly, MoveOnly> t(MoveOnly(0), MoveOnly(1));
42 BOOST_HANA_RUNTIME_CHECK(hana::at_c<0>(t) == 0);
43 BOOST_HANA_RUNTIME_CHECK(hana::at_c<1>(t) == 1);
44 }
45 {
46 hana::tuple<MoveOnly, MoveOnly, MoveOnly> t(
47 MoveOnly(0), MoveOnly(1), MoveOnly(2)
48 );
49 BOOST_HANA_RUNTIME_CHECK(hana::at_c<0>(t) == 0);
50 BOOST_HANA_RUNTIME_CHECK(hana::at_c<1>(t) == 1);
51 BOOST_HANA_RUNTIME_CHECK(hana::at_c<2>(t) == 2);
52 }
53 {
54 constexpr hana::tuple<Empty> t0{Empty()}; (void)t0;
55 }
56 {
57 constexpr hana::tuple<A, A> t(3, 2);
58 static_assert(hana::at_c<0>(xs: t).id_ == 3, "");
59 }
60 {
61 typedef hana::tuple<MoveOnly, NoDefault> Tuple;
62
63 static_assert(!std::is_constructible<
64 Tuple,
65 MoveOnly
66 >::value, "");
67
68 static_assert(std::is_constructible<
69 Tuple,
70 MoveOnly, NoDefault
71 >::value, "");
72 }
73 {
74 typedef hana::tuple<MoveOnly, MoveOnly, NoDefault> Tuple;
75
76 static_assert(!std::is_constructible<
77 Tuple,
78 MoveOnly, MoveOnly
79 >::value, "");
80
81 static_assert(std::is_constructible<
82 Tuple,
83 MoveOnly, MoveOnly, NoDefault
84 >::value, "");
85 }
86 {
87 typedef hana::tuple<MoveOnly, NoDefault> Tuple;
88 typedef hana::tuple<MoveOnly, Tuple, MoveOnly, MoveOnly> NestedTuple;
89
90 static_assert(!std::is_constructible<
91 NestedTuple,
92 MoveOnly, MoveOnly, MoveOnly, MoveOnly
93 >::value, "");
94
95 static_assert(std::is_constructible<
96 NestedTuple,
97 MoveOnly, Tuple, MoveOnly, MoveOnly
98 >::value, "");
99 }
100 {
101 typedef hana::tuple<MoveOnly, int> Tuple;
102 typedef hana::tuple<MoveOnly, Tuple, MoveOnly, MoveOnly> NestedTuple;
103
104 static_assert(!std::is_constructible<
105 NestedTuple,
106 MoveOnly, MoveOnly, MoveOnly, MoveOnly
107 >::value, "");
108
109 static_assert(std::is_constructible<
110 NestedTuple,
111 MoveOnly, Tuple, MoveOnly, MoveOnly
112 >::value, "");
113 }
114}
115

source code of boost/libs/hana/test/tuple/cnstr.variadic_forward.cpp