| // Copyright (C) 2019-2021 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 run { target c++2a } } |
| |
| #include <ranges> |
| #include <utility> // as_const |
| #include <testsuite_hooks.h> |
| |
| void |
| test01() |
| { |
| std::ranges::single_view s{4}; |
| static_assert(std::same_as<std::ranges::range_value_t<decltype(s)>, int>); |
| static_assert(std::ranges::size(s) == 1); |
| |
| int count = 0; |
| for (auto i : s) |
| ++count; |
| VERIFY(count == 1); |
| VERIFY(*std::ranges::begin(s) == 4); |
| } |
| |
| void |
| test02() |
| { |
| std::ranges::single_view<long> s2; |
| static_assert(std::same_as<std::ranges::range_value_t<decltype(s2)>, long>); |
| static_assert(std::ranges::size(s2) == 1); |
| |
| int count = 0; |
| for (auto l : s2) |
| ++count; |
| VERIFY(count == 1); |
| VERIFY(*std::ranges::begin(s2) == 0L); |
| } |
| |
| void |
| test03() |
| { |
| auto s3 = std::ranges::views::single('a'); |
| static_assert(std::same_as<std::ranges::range_value_t<decltype(s3)>, char>); |
| static_assert(std::ranges::size(s3) == 1); |
| VERIFY(*std::ranges::begin(s3) == 'a'); |
| } |
| |
| void |
| test04() |
| { |
| // PR libstdc++/100475 |
| struct A { |
| A() = default; |
| A(int, int) { } |
| A(std::initializer_list<int>) = delete; |
| void operator&() const = delete; |
| }; |
| std::ranges::single_view<A> s(std::in_place, 0, 0); |
| s.data(); |
| std::as_const(s).data(); |
| } |
| |
| void |
| test05() |
| { |
| int i = 0; |
| static_assert(noexcept(std::ranges::single_view<int>())); |
| static_assert(noexcept(std::ranges::single_view<int>(i))); |
| static_assert(noexcept(std::ranges::single_view<int>(1))); |
| static_assert(noexcept(std::ranges::single_view<int>(std::in_place, 2))); |
| static_assert(noexcept(std::ranges::views::single(i))); |
| auto s = std::ranges::views::single(i); |
| static_assert(noexcept(s.begin())); |
| static_assert(noexcept(s.end())); |
| static_assert(noexcept(s.size())); |
| static_assert(noexcept(s.data())); |
| static_assert(noexcept(s.empty())); // view_interface::empty() |
| const auto cs = s; |
| static_assert(noexcept(cs.begin())); |
| static_assert(noexcept(cs.end())); |
| static_assert(noexcept(cs.size())); |
| static_assert(noexcept(cs.data())); |
| static_assert(noexcept(cs.empty())); // view_interface::empty() |
| } |
| |
| void |
| test06() |
| { |
| // PR libstdc++/100475 comment #7 |
| struct S { |
| S() = default; |
| S(std::initializer_list<S>) = delete; |
| S(const S&) {} |
| }; |
| S obj; |
| auto x = std::views::single(obj); |
| auto y = std::views::single(std::move(obj)); |
| } |
| |
| int main() |
| { |
| test01(); |
| test02(); |
| test03(); |
| test04(); |
| test05(); |
| test06(); |
| } |