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// constexpr explicit sentinel(sentinel_t<Base> end);
12
13#include <cassert>
14#include <ranges>
15#include <tuple>
16#include <utility>
17
18struct Sent {
19 int i;
20
21 friend constexpr bool operator==(std::tuple<int>*, const Sent&) { return true; }
22};
23
24struct Range : std::ranges::view_base {
25 std::tuple<int>* begin() const;
26 Sent end();
27};
28
29// Test explicit
30
31static_assert(std::is_constructible_v<std::ranges::sentinel_t<std::ranges::elements_view<Range, 0>>, Sent>);
32static_assert(!std::is_convertible_v<Sent, std::ranges::sentinel_t<std::ranges::elements_view<Range, 0>>>);
33
34constexpr bool test() {
35 // base is init correctly
36 {
37 using R = std::ranges::elements_view<Range, 0>;
38 using Sentinel = std::ranges::sentinel_t<R>;
39
40 Sentinel s1(Sent{5});
41 assert(s1.base().i == 5);
42 }
43
44 return true;
45}
46
47int main(int, char**) {
48 test();
49 static_assert(test());
50
51 return 0;
52}
53

source code of libcxx/test/std/ranges/range.adaptors/range.elements/sentinel/ctor.base.pass.cpp