| // Copyright (C) 2021 Free Software Foundation, Inc. |
| // |
| // This file is part of the GNU ISO C++ Library. This library is free |
| // software; you can redistribute it and/or modify it under the |
| // terms of the GNU General Public License as published by the |
| // Free Software Foundation; either version 3, or (at your option) |
| // any later version. |
| |
| // This library is distributed in the hope that it will be useful, |
| // but WITHOUT ANY WARRANTY; without even the implied warranty of |
| // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| // GNU General Public License for more details. |
| |
| // You should have received a copy of the GNU General Public License along |
| // with this library; see the file COPYING3. If not see |
| // <http://www.gnu.org/licenses/>. |
| |
| // { dg-options "-std=gnu++2a" } |
| // { dg-do compile { target c++2a } } |
| |
| // Verify P2259 changes. |
| |
| #include <ranges> |
| #include <tuple> |
| #include <vector> |
| |
| namespace ranges = std::ranges; |
| namespace views = std::views; |
| |
| using std::__detail::__iter_without_category; |
| |
| template<typename _Range> |
| concept only_cxx20_input_range = ranges::input_range<_Range> |
| && !ranges::forward_range<_Range> |
| && __iter_without_category<ranges::iterator_t<_Range>>; |
| |
| void |
| test01() |
| { |
| extern std::vector<int> vec; |
| only_cxx20_input_range auto v0 |
| = vec |
| | views::transform([](int c) { return views::single(c); }) |
| | views::join; |
| |
| // Verify the changes to filter_view. |
| only_cxx20_input_range auto v1 = v0 | views::filter([](int c) { return c > 0; }); |
| |
| // Verify the changes to transform_view. |
| only_cxx20_input_range auto v2 = v0 | views::transform([](int& c) -> auto& { return c; }); |
| |
| // Verify the changes to lazy_split_view. |
| only_cxx20_input_range auto v3 = v0 | views::lazy_split(12); |
| static_assert(only_cxx20_input_range<decltype(*v3.begin())>); |
| |
| // Verify the changes to join_view. |
| only_cxx20_input_range auto v4 = v0 | views::lazy_split(12) | views::join; |
| |
| // Verify the changes to elements_view. |
| only_cxx20_input_range auto v5 |
| = v0 |
| | views::transform([](int c) { return std::make_tuple(c, c); }) |
| | views::elements<0>; |
| |
| // Verify the changes to common_iterator. |
| only_cxx20_input_range auto v6 = v0 | views::common; |
| (void) *(v6.begin()++); |
| |
| // Verify the changes to iota_view. |
| only_cxx20_input_range auto v8 = ranges::iota_view{v0.begin()}; |
| |
| // Verify the changes to move_iterator. |
| __iter_without_category auto i9 = std::make_move_iterator(v0.begin()); |
| |
| // Verify the changes to counted_iterator. |
| extern std::counted_iterator<int*> i10; |
| static_assert(std::contiguous_iterator<decltype(i10)>); |
| static_assert(std::same_as<std::iterator_traits<decltype(i10)>::iterator_category, |
| std::random_access_iterator_tag>); |
| (void) i10.operator->(); |
| __iter_without_category auto i11 = std::counted_iterator{v0.begin(), 5}; |
| } |
| |
| void |
| test02() |
| { |
| // Verify LWG 3291 example. |
| auto v = views::iota(0); |
| auto i = std::counted_iterator{v.begin(), 5}; |
| static_assert(std::random_access_iterator<decltype(i)>); |
| } |