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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 assignable_from<I&, const I2&>
// constexpr counted_iterator& operator=(const counted_iterator<I2>& x);
#include <iterator>
#include "test_macros.h"
#include "test_iterators.h"
class AssignableFromIter
{
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;
friend constexpr int *base(const AssignableFromIter& i) {return i.it_;}
AssignableFromIter() = default;
explicit constexpr AssignableFromIter(int *it) : it_(it) {}
constexpr AssignableFromIter(const forward_iterator<int*>& it) : it_(base(it)) {}
constexpr AssignableFromIter& operator=(const forward_iterator<int*> &other) {
it_ = base(other);
return *this;
}
constexpr reference operator*() const {return *it_;}
constexpr AssignableFromIter& operator++() {++it_; return *this;}
constexpr AssignableFromIter operator++(int)
{AssignableFromIter tmp(*this); ++(*this); return tmp;}
};
struct InputOrOutputArchetype {
using difference_type = int;
int *ptr;
int operator*() { return *ptr; }
void operator++(int) { ++ptr; }
InputOrOutputArchetype& operator++() { ++ptr; return *this; }
};
constexpr bool test() {
int buffer[8] = {1, 2, 3, 4, 5, 6, 7, 8};
{
static_assert( std::is_assignable_v<std::counted_iterator<forward_iterator<int*>>,
std::counted_iterator<forward_iterator<int*>>>);
static_assert(!std::is_assignable_v<std::counted_iterator<forward_iterator<int*>>,
std::counted_iterator<random_access_iterator<int*>>>);
}
{
std::counted_iterator iter1(AssignableFromIter{buffer}, 8);
std::counted_iterator iter2(forward_iterator<int*>{buffer + 2}, 6);
assert(base(iter1.base()) == buffer);
assert(iter1.count() == 8);
std::counted_iterator<AssignableFromIter>& result = (iter1 = iter2);
assert(&result == &iter1);
assert(base(iter1.base()) == buffer + 2);
assert(iter1.count() == 6);
ASSERT_SAME_TYPE(decltype(iter1 = iter2), std::counted_iterator<AssignableFromIter>&);
}
{
std::counted_iterator iter1(AssignableFromIter{buffer}, 8);
const std::counted_iterator iter2(forward_iterator<int*>{buffer + 2}, 6);
assert(base(iter1.base()) == buffer);
assert(iter1.count() == 8);
std::counted_iterator<AssignableFromIter>& result = (iter1 = iter2);
assert(&result == &iter1);
assert(base(iter1.base()) == buffer + 2);
assert(iter1.count() == 6);
ASSERT_SAME_TYPE(decltype(iter1 = iter2), std::counted_iterator<AssignableFromIter>&);
}
{
std::counted_iterator iter1(InputOrOutputArchetype{buffer}, 8);
std::counted_iterator iter2(InputOrOutputArchetype{buffer + 2}, 6);
assert(iter1.base().ptr == buffer);
assert(iter1.count() == 8);
std::counted_iterator<InputOrOutputArchetype>& result = (iter1 = iter2);
assert(&result == &iter1);
assert(iter1.base().ptr == buffer + 2);
assert(iter1.count() == 6);
ASSERT_SAME_TYPE(decltype(iter1 = iter2), std::counted_iterator<InputOrOutputArchetype>&);
}
{
std::counted_iterator iter1(InputOrOutputArchetype{buffer}, 8);
const std::counted_iterator iter2(InputOrOutputArchetype{buffer + 2}, 6);
assert(iter1.base().ptr == buffer);
assert(iter1.count() == 8);
std::counted_iterator<InputOrOutputArchetype>& result = (iter1 = iter2);
assert(&result == &iter1);
assert(iter1.base().ptr == buffer + 2);
assert(iter1.count() == 6);
ASSERT_SAME_TYPE(decltype(iter1 = iter2), std::counted_iterator<InputOrOutputArchetype>&);
}
return true;
}
int main(int, char**) {
test();
static_assert(test());
return 0;
}
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