| //===----------------------------------------------------------------------===// |
| // |
| // 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 |
| |
| // constexpr iter_difference_t<I> count() const noexcept; |
| |
| #include <iterator> |
| |
| #include "test_macros.h" |
| #include "test_iterators.h" |
| |
| struct InputOrOutputArchetype { |
| using difference_type = int; |
| |
| int *ptr; |
| |
| constexpr int operator*() { return *ptr; } |
| constexpr void operator++(int) { ++ptr; } |
| constexpr InputOrOutputArchetype& operator++() { ++ptr; return *this; } |
| }; |
| |
| constexpr bool test() { |
| int buffer[8] = {1, 2, 3, 4, 5, 6, 7, 8}; |
| |
| { |
| std::counted_iterator iter(cpp20_input_iterator<int*>{buffer}, 8); |
| for (int i = 8; i != 0; --i, ++iter) |
| assert(iter.count() == i); |
| |
| static_assert(noexcept(iter.count())); |
| } |
| { |
| std::counted_iterator iter(forward_iterator<int*>{buffer}, 8); |
| for (int i = 8; i != 0; --i, ++iter) |
| assert(iter.count() == i); |
| |
| static_assert(noexcept(iter.count())); |
| } |
| { |
| std::counted_iterator iter(contiguous_iterator<int*>{buffer}, 8); |
| for (int i = 8; i != 0; --i, ++iter) |
| assert(iter.count() == i); |
| } |
| { |
| std::counted_iterator iter(InputOrOutputArchetype{buffer + 2}, 6); |
| assert(iter.count() == 6); |
| } |
| |
| // Const tests. |
| { |
| const std::counted_iterator iter(cpp20_input_iterator<int*>{buffer}, 8); |
| assert(iter.count() == 8); |
| } |
| { |
| const std::counted_iterator iter(forward_iterator<int*>{buffer + 1}, 7); |
| assert(iter.count() == 7); |
| } |
| { |
| const std::counted_iterator iter(contiguous_iterator<int*>{buffer + 2}, 6); |
| assert(iter.count() == 6); |
| } |
| { |
| const std::counted_iterator iter(InputOrOutputArchetype{buffer + 2}, 6); |
| assert(iter.count() == 6); |
| } |
| |
| return true; |
| } |
| |
| int main(int, char**) { |
| test(); |
| static_assert(test()); |
| |
| return 0; |
| } |