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 // template<class I2>
12 // requires convertible_to<const I2&, I>
13 // constexpr counted_iterator(const counted_iterator<I2>& x);
14
15 #include <iterator>
16
17 #include "test_macros.h"
18 #include "test_iterators.h"
19
20 template<class T>
21 class ConvertibleTo
22 {
23 int *it_;
24
25 public:
26 typedef std::input_iterator_tag iterator_category;
27 typedef int value_type;
28 typedef typename std::iterator_traits<int *>::difference_type difference_type;
29 typedef int * pointer;
30 typedef int & reference;
31
base() const32 constexpr int *base() const {return it_;}
33
34 ConvertibleTo() = default;
ConvertibleTo(int * it)35 explicit constexpr ConvertibleTo(int *it) : it_(it) {}
36
operator *() const37 constexpr reference operator*() const {return *it_;}
38
operator ++()39 constexpr ConvertibleTo& operator++() {++it_; return *this;}
operator ++(int)40 constexpr ConvertibleTo operator++(int)
41 {ConvertibleTo tmp(*this); ++(*this); return tmp;}
42
operator T() const43 constexpr operator T() const { return T(it_); }
44 };
45
test()46 constexpr bool test() {
47 int buffer[8] = {1, 2, 3, 4, 5, 6, 7, 8};
48
49 {
50 static_assert( std::is_constructible_v<std::counted_iterator<forward_iterator<int*>>,
51 std::counted_iterator<forward_iterator<int*>>>);
52 static_assert(!std::is_constructible_v<std::counted_iterator<forward_iterator<int*>>,
53 std::counted_iterator<random_access_iterator<int*>>>);
54 }
55 {
56 std::counted_iterator iter1(ConvertibleTo<forward_iterator<int*>>{buffer}, 8);
57 std::counted_iterator<forward_iterator<int*>> iter2(iter1);
58 assert(iter2.base() == forward_iterator<int*>{buffer});
59 assert(iter2.count() == 8);
60 }
61 {
62 const std::counted_iterator iter1(ConvertibleTo<forward_iterator<int*>>{buffer}, 8);
63 const std::counted_iterator<forward_iterator<int*>> iter2(iter1);
64 assert(iter2.base() == forward_iterator<int*>{buffer});
65 assert(iter2.count() == 8);
66 }
67
68 return true;
69 }
70
main(int,char **)71 int main(int, char**) {
72 test();
73 static_assert(test());
74
75 return 0;
76 }
77