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 // template<class S2>
16 //    requires convertible_to<const S2&, S>
17 //      constexpr move_sentinel(const move_sentinel<S2>& s);
18 
19 #include <cassert>
20 #include <concepts>
21 #include <iterator>
22 #include <type_traits>
23 
24 struct NonConvertible {
25     explicit NonConvertible();
26     NonConvertible(int i);
27     explicit NonConvertible(long i) = delete;
28 };
29 static_assert(std::semiregular<NonConvertible>);
30 static_assert(std::is_convertible_v<long, NonConvertible>);
31 static_assert(!std::convertible_to<long, NonConvertible>);
32 
test()33 constexpr bool test()
34 {
35   // Constructing from an lvalue.
36   {
37     std::move_sentinel<int> m(42);
38     std::move_sentinel<long> m2 = m;
39     assert(m2.base() == 42L);
40   }
41 
42   // Constructing from an rvalue.
43   {
44     std::move_sentinel<long> m2 = std::move_sentinel<int>(43);
45     assert(m2.base() == 43L);
46   }
47 
48   // SFINAE checks.
49   {
50     static_assert( std::is_convertible_v<std::move_sentinel<int>, std::move_sentinel<long>>);
51     static_assert( std::is_convertible_v<std::move_sentinel<int*>, std::move_sentinel<const int*>>);
52     static_assert(!std::is_convertible_v<std::move_sentinel<const int*>, std::move_sentinel<int*>>);
53     static_assert( std::is_convertible_v<std::move_sentinel<int>, std::move_sentinel<NonConvertible>>);
54     static_assert(!std::is_convertible_v<std::move_sentinel<long>, std::move_sentinel<NonConvertible>>);
55   }
56   return true;
57 }
58 
main(int,char **)59 int main(int, char**)
60 {
61   test();
62   static_assert(test());
63 
64   return 0;
65 }
66