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 iota_view(W value);
12
13 #include <cassert>
14 #include <ranges>
15 #include <type_traits>
16
17 #include "test_macros.h"
18 #include "types.h"
19
20 struct SomeIntComparable {
21 using difference_type = int;
22
23 SomeInt value_;
SomeIntComparableSomeIntComparable24 constexpr SomeIntComparable() : value_(SomeInt(10)) {}
25
operator ==(SomeIntComparable lhs,SomeIntComparable rhs)26 friend constexpr bool operator==(SomeIntComparable lhs, SomeIntComparable rhs) {
27 return lhs.value_ == rhs.value_;
28 }
operator ==(SomeIntComparable lhs,SomeInt rhs)29 friend constexpr bool operator==(SomeIntComparable lhs, SomeInt rhs) {
30 return lhs.value_ == rhs;
31 }
operator ==(SomeInt lhs,SomeIntComparable rhs)32 friend constexpr bool operator==(SomeInt lhs, SomeIntComparable rhs) {
33 return lhs == rhs.value_;
34 }
35
operator -(SomeIntComparable lhs,SomeIntComparable rhs)36 friend constexpr difference_type operator-(SomeIntComparable lhs, SomeIntComparable rhs) {
37 return lhs.value_ - rhs.value_;
38 }
39
operator ++SomeIntComparable40 constexpr SomeIntComparable& operator++() { ++value_; return *this; }
operator ++SomeIntComparable41 constexpr SomeIntComparable operator++(int) { auto tmp = *this; ++value_; return tmp; }
operator --SomeIntComparable42 constexpr SomeIntComparable operator--() { --value_; return *this; }
43 };
44
test()45 constexpr bool test() {
46 {
47 std::ranges::iota_view<SomeInt> io(SomeInt(42));
48 assert((*io.begin()).value_ == 42);
49 // Check that end returns std::unreachable_sentinel.
50 assert(io.end() != io.begin());
51 static_assert(std::same_as<decltype(io.end()), std::unreachable_sentinel_t>);
52 }
53
54 {
55 std::ranges::iota_view<SomeInt, SomeIntComparable> io(SomeInt(0));
56 assert(std::ranges::next(io.begin(), 10) == io.end());
57 }
58 {
59 static_assert(!std::is_convertible_v<std::ranges::iota_view<SomeInt>, SomeInt>);
60 static_assert( std::is_constructible_v<std::ranges::iota_view<SomeInt>, SomeInt>);
61 }
62
63 return true;
64 }
65
main(int,char **)66 int main(int, char**) {
67 test();
68 static_assert(test());
69
70 return 0;
71 }
72