88 lines
2.2 KiB
C++
88 lines
2.2 KiB
C++
//===----------------------------------------------------------------------===//
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//
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// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
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// See https://llvm.org/LICENSE.txt for license information.
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// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
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//
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//===----------------------------------------------------------------------===//
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// UNSUPPORTED: c++03, c++11, c++14, c++17
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// constexpr V base() const & requires copy_constructible<V> { return base_; }
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// constexpr V base() && { return std::move(base_); }
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#include <cassert>
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#include <ranges>
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#include <type_traits>
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#include <utility>
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#include "MoveOnly.h"
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#include "types.h"
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struct View : std::ranges::view_interface<View> {
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int i;
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int* begin() const;
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int* end() const;
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};
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struct MoveOnlyView : View {
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MoveOnly mo;
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};
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template <class T>
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concept HasBase = requires(T&& t) { std::forward<T>(t).base(); };
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struct Pred {
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constexpr bool operator()(int i) const { return i > 5; }
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};
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static_assert(HasBase<std::ranges::take_while_view<View, Pred> const&>);
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static_assert(HasBase<std::ranges::take_while_view<View, Pred>&&>);
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static_assert(!HasBase<std::ranges::take_while_view<MoveOnlyView, Pred> const&>);
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static_assert(HasBase<std::ranges::take_while_view<MoveOnlyView, Pred>&&>);
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constexpr bool test() {
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// const &
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{
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const std::ranges::take_while_view<View, Pred> twv{View{{}, 5}, {}};
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std::same_as<View> decltype(auto) v = twv.base();
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assert(v.i == 5);
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}
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// &
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{
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std::ranges::take_while_view<View, Pred> twv{View{{}, 5}, {}};
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std::same_as<View> decltype(auto) v = twv.base();
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assert(v.i == 5);
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}
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// &&
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{
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std::ranges::take_while_view<View, Pred> twv{View{{}, 5}, {}};
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std::same_as<View> decltype(auto) v = std::move(twv).base();
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assert(v.i == 5);
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}
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// const &&
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{
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const std::ranges::take_while_view<View, Pred> twv{View{{}, 5}, {}};
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std::same_as<View> decltype(auto) v = std::move(twv).base();
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assert(v.i == 5);
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}
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// move only
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{
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std::ranges::take_while_view<MoveOnlyView, Pred> twv{MoveOnlyView{{}, 5}, {}};
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std::same_as<MoveOnlyView> decltype(auto) v = std::move(twv).base();
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assert(v.mo.get() == 5);
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}
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return true;
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}
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int main(int, char**) {
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test();
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static_assert(test());
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return 0;
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}
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