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// UNSUPPORTED: c++03, c++11, c++14, c++17
10
11// <ranges>
12
13// template<class T>
14// concept view = ...;
15
16#include <ranges>
17
18// The type would be a view, but it's not moveable.
19struct NotMoveable : std::ranges::view_base {
20 NotMoveable() = default;
21 NotMoveable(NotMoveable&&) = delete;
22 NotMoveable& operator=(NotMoveable&&) = delete;
23 friend int* begin(NotMoveable&);
24 friend int* begin(NotMoveable const&);
25 friend int* end(NotMoveable&);
26 friend int* end(NotMoveable const&);
27};
28static_assert(std::ranges::range<NotMoveable>);
29static_assert(!std::movable<NotMoveable>);
30static_assert(std::default_initializable<NotMoveable>);
31static_assert(std::ranges::enable_view<NotMoveable>);
32static_assert(!std::ranges::view<NotMoveable>);
33
34// The type would be a view, but it's not default initializable
35struct NotDefaultInit : std::ranges::view_base {
36 NotDefaultInit() = delete;
37 friend int* begin(NotDefaultInit&);
38 friend int* begin(NotDefaultInit const&);
39 friend int* end(NotDefaultInit&);
40 friend int* end(NotDefaultInit const&);
41};
42static_assert(std::ranges::range<NotDefaultInit>);
43static_assert(std::movable<NotDefaultInit>);
44static_assert(!std::default_initializable<NotDefaultInit>);
45static_assert(std::ranges::enable_view<NotDefaultInit>);
46static_assert(std::ranges::view<NotDefaultInit>);
47
48// The type would be a view, but it doesn't enable it with enable_view
49struct NotExplicitlyEnabled {
50 NotExplicitlyEnabled() = default;
51 NotExplicitlyEnabled(NotExplicitlyEnabled&&) = default;
52 NotExplicitlyEnabled& operator=(NotExplicitlyEnabled&&) = default;
53 friend int* begin(NotExplicitlyEnabled&);
54 friend int* begin(NotExplicitlyEnabled const&);
55 friend int* end(NotExplicitlyEnabled&);
56 friend int* end(NotExplicitlyEnabled const&);
57};
58static_assert(std::ranges::range<NotExplicitlyEnabled>);
59static_assert(std::movable<NotExplicitlyEnabled>);
60static_assert(std::default_initializable<NotExplicitlyEnabled>);
61static_assert(!std::ranges::enable_view<NotExplicitlyEnabled>);
62static_assert(!std::ranges::view<NotExplicitlyEnabled>);
63
64// The type has everything else, but it's not a range
65struct NotARange : std::ranges::view_base {
66 NotARange() = default;
67 NotARange(NotARange&&) = default;
68 NotARange& operator=(NotARange&&) = default;
69};
70static_assert(!std::ranges::range<NotARange>);
71static_assert(std::movable<NotARange>);
72static_assert(std::default_initializable<NotARange>);
73static_assert(std::ranges::enable_view<NotARange>);
74static_assert(!std::ranges::view<NotARange>);
75
76// The type satisfies all requirements
77struct View : std::ranges::view_base {
78 View() = default;
79 View(View&&) = default;
80 View& operator=(View&&) = default;
81 friend int* begin(View&);
82 friend int* begin(View const&);
83 friend int* end(View&);
84 friend int* end(View const&);
85};
86static_assert(std::ranges::range<View>);
87static_assert(std::movable<View>);
88static_assert(std::default_initializable<View>);
89static_assert(std::ranges::enable_view<View>);
90static_assert(std::ranges::view<View>);
91
92// const view types
93
94struct ConstView1 : std::ranges::view_base {
95 ConstView1(const ConstView1&&);
96 const ConstView1& operator=(const ConstView1&&) const;
97
98 friend void swap(const ConstView1&, const ConstView1&);
99
100 friend int* begin(const ConstView1&);
101 friend int* end(const ConstView1&);
102};
103static_assert(std::ranges::range<const ConstView1>);
104static_assert(std::movable<const ConstView1>);
105static_assert(!std::default_initializable<const ConstView1>);
106static_assert(std::ranges::enable_view<const ConstView1>);
107static_assert(std::ranges::view<const ConstView1>);
108
109struct ConstView2 : std::ranges::view_interface<ConstView2> {
110 ConstView2(const ConstView2&&);
111 const ConstView2& operator=(const ConstView2&&) const;
112
113 friend void swap(const ConstView2&, const ConstView2&);
114
115 friend int* begin(const ConstView2&);
116 friend int* end(const ConstView2&);
117};
118static_assert(std::ranges::range<const ConstView2>);
119static_assert(std::movable<const ConstView2>);
120static_assert(!std::default_initializable<const ConstView2>);
121static_assert(std::ranges::enable_view<const ConstView2>);
122static_assert(std::ranges::view<const ConstView2>);
123
124// volatile view types
125struct VolatileView1 : std::ranges::view_base {
126 VolatileView1(volatile VolatileView1&&);
127 volatile VolatileView1& operator=(volatile VolatileView1&&) volatile;
128
129 friend void swap(volatile VolatileView1&, volatile VolatileView1&);
130
131 friend int* begin(volatile VolatileView1&);
132 friend int* end(volatile VolatileView1&);
133};
134static_assert(std::ranges::range<volatile VolatileView1>);
135static_assert(std::movable<volatile VolatileView1>);
136static_assert(!std::default_initializable<volatile VolatileView1>);
137static_assert(std::ranges::enable_view<volatile VolatileView1>);
138static_assert(std::ranges::view<volatile VolatileView1>);
139
140struct VolatileView2 : std::ranges::view_interface<VolatileView2> {
141 VolatileView2(volatile VolatileView2&&);
142 volatile VolatileView2& operator=(volatile VolatileView2&&) volatile;
143
144 friend void swap(volatile VolatileView2&, volatile VolatileView2&);
145
146 friend int* begin(volatile VolatileView2&);
147 friend int* end(volatile VolatileView2&);
148};
149static_assert(std::ranges::range<volatile VolatileView2>);
150static_assert(std::movable<volatile VolatileView2>);
151static_assert(!std::default_initializable<volatile VolatileView2>);
152static_assert(std::ranges::enable_view<volatile VolatileView2>);
153static_assert(std::ranges::view<volatile VolatileView2>);
154
155// const-volatile view types
156
157struct ConstVolatileView1 : std::ranges::view_base {
158 ConstVolatileView1(const volatile ConstVolatileView1&&);
159 const volatile ConstVolatileView1& operator=(const volatile ConstVolatileView1&&) const volatile;
160
161 friend void swap(const volatile ConstVolatileView1&, const volatile ConstVolatileView1&);
162
163 friend int* begin(const volatile ConstVolatileView1&);
164 friend int* end(const volatile ConstVolatileView1&);
165};
166static_assert(std::ranges::range<const volatile ConstVolatileView1>);
167static_assert(std::movable<const volatile ConstVolatileView1>);
168static_assert(!std::default_initializable<const volatile ConstVolatileView1>);
169static_assert(std::ranges::enable_view<const volatile ConstVolatileView1>);
170static_assert(std::ranges::view<const volatile ConstVolatileView1>);
171
172struct ConstVolatileView2 : std::ranges::view_interface<ConstVolatileView2> {
173 ConstVolatileView2(const volatile ConstVolatileView2&&);
174 const volatile ConstVolatileView2& operator=(const volatile ConstVolatileView2&&) const volatile;
175
176 friend void swap(const volatile ConstVolatileView2&, const volatile ConstVolatileView2&);
177
178 friend int* begin(const volatile ConstVolatileView2&);
179 friend int* end(const volatile ConstVolatileView2&);
180};
181static_assert(std::ranges::range<const volatile ConstVolatileView2>);
182static_assert(std::movable<const volatile ConstVolatileView2>);
183static_assert(!std::default_initializable<const volatile ConstVolatileView2>);
184static_assert(std::ranges::enable_view<const volatile ConstVolatileView2>);
185static_assert(std::ranges::view<const volatile ConstVolatileView2>);
186

source code of libcxx/test/std/ranges/range.req/range.view/view.compile.pass.cpp