| //===----------------------------------------------------------------------===// |
| // |
| // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. |
| // See https://llvm.org/LICENSE.txt for license information. |
| // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception |
| // |
| //===----------------------------------------------------------------------===// |
| |
| // UNSUPPORTED: c++03, c++11, c++14, c++17 |
| // UNSUPPORTED: libcpp-no-concepts |
| // UNSUPPORTED: gcc-10 |
| |
| // template<class I2> |
| // requires convertible_to<const I2&, I> |
| // constexpr counted_iterator(const counted_iterator<I2>& x); |
| |
| #include <iterator> |
| |
| #include "test_macros.h" |
| #include "test_iterators.h" |
| |
| template<class T> |
| class ConvertibleTo |
| { |
| int *it_; |
| |
| public: |
| typedef std::input_iterator_tag iterator_category; |
| typedef int value_type; |
| typedef typename std::iterator_traits<int *>::difference_type difference_type; |
| typedef int * pointer; |
| typedef int & reference; |
| |
| constexpr int *base() const {return it_;} |
| |
| ConvertibleTo() = default; |
| explicit constexpr ConvertibleTo(int *it) : it_(it) {} |
| |
| constexpr reference operator*() const {return *it_;} |
| |
| constexpr ConvertibleTo& operator++() {++it_; return *this;} |
| constexpr ConvertibleTo operator++(int) |
| {ConvertibleTo tmp(*this); ++(*this); return tmp;} |
| |
| constexpr operator T() const { return T(it_); } |
| }; |
| |
| constexpr bool test() { |
| int buffer[8] = {1, 2, 3, 4, 5, 6, 7, 8}; |
| |
| { |
| static_assert( std::is_constructible_v<std::counted_iterator<forward_iterator<int*>>, |
| std::counted_iterator<forward_iterator<int*>>>); |
| static_assert(!std::is_constructible_v<std::counted_iterator<forward_iterator<int*>>, |
| std::counted_iterator<random_access_iterator<int*>>>); |
| } |
| { |
| std::counted_iterator iter1(ConvertibleTo<forward_iterator<int*>>{buffer}, 8); |
| std::counted_iterator<forward_iterator<int*>> iter2(iter1); |
| assert(iter2.base() == forward_iterator<int*>{buffer}); |
| assert(iter2.count() == 8); |
| } |
| { |
| const std::counted_iterator iter1(ConvertibleTo<forward_iterator<int*>>{buffer}, 8); |
| const std::counted_iterator<forward_iterator<int*>> iter2(iter1); |
| assert(iter2.base() == forward_iterator<int*>{buffer}); |
| assert(iter2.count() == 8); |
| } |
| |
| return true; |
| } |
| |
| int main(int, char**) { |
| test(); |
| static_assert(test()); |
| |
| return 0; |
| } |