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//===----------------------------------------------------------------------===//
//
// 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
// 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;
}
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