| //===----------------------------------------------------------------------===// |
| // |
| // 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 |
| |
| // drop_while_view() requires default_initializable<V> && default_initializable<Pred> = default; |
| |
| #include <cassert> |
| #include <ranges> |
| #include <type_traits> |
| |
| template <bool DefaultInitializable> |
| struct View : std::ranges::view_base { |
| int i = 42; |
| constexpr explicit View() |
| requires DefaultInitializable |
| = default; |
| int* begin() const; |
| int* end() const; |
| }; |
| |
| template <bool DefaultInitializable> |
| struct Pred { |
| int i = 42; |
| constexpr explicit Pred() |
| requires DefaultInitializable |
| = default; |
| bool operator()(int) const; |
| }; |
| |
| // clang-format off |
| static_assert( std::is_default_constructible_v<std::ranges::drop_while_view<View<true >, Pred<true >>>); |
| static_assert(!std::is_default_constructible_v<std::ranges::drop_while_view<View<false>, Pred<true >>>); |
| static_assert(!std::is_default_constructible_v<std::ranges::drop_while_view<View<true >, Pred<false>>>); |
| static_assert(!std::is_default_constructible_v<std::ranges::drop_while_view<View<false>, Pred<false>>>); |
| // clang-format on |
| |
| constexpr bool test() { |
| { |
| std::ranges::drop_while_view<View<true>, Pred<true>> dwv = {}; |
| assert(dwv.base().i == 42); |
| assert(dwv.pred().i == 42); |
| } |
| return true; |
| } |
| |
| int main(int, char**) { |
| test(); |
| static_assert(test()); |
| return 0; |
| } |