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 // <iterator>
12 
13 // move_sentinel
14 
15 // constexpr explicit move_sentinel(S s);
16 
17 #include <cassert>
18 #include <iterator>
19 #include <type_traits>
20 
test()21 constexpr bool test()
22 {
23   // The underlying sentinel is an integer.
24   {
25     static_assert(!std::is_convertible_v<int, std::move_sentinel<int>>);
26     std::move_sentinel<int> m(42);
27     assert(m.base() == 42);
28   }
29 
30   // The underlying sentinel is a pointer.
31   {
32     static_assert(!std::is_convertible_v<int*, std::move_sentinel<int*>>);
33     int i = 42;
34     std::move_sentinel<int*> m(&i);
35     assert(m.base() == &i);
36   }
37 
38   // The underlying sentinel is a user-defined type with an explicit default constructor.
39   {
40     struct S {
41       explicit S() = default;
42       constexpr explicit S(int j) : i(j) {}
43       int i = 3;
44     };
45     static_assert(!std::is_convertible_v<S, std::move_sentinel<S>>);
46     std::move_sentinel<S> m(S(42));
47     assert(m.base().i == 42);
48   }
49   return true;
50 }
51 
main(int,char **)52 int main(int, char**)
53 {
54   test();
55   static_assert(test());
56 
57   return 0;
58 }
59