40aaa272f1
Implemented [[ https://www.open-std.org/jtc1/sc22/wg21/docs/papers/2022/p2711r1.html | P2711R1 ]] for existing views. (`join_with_view` is not yet implemented) Reviewed By: #libc, philnik Differential Revision: https://reviews.llvm.org/D144822
67 lines
1.6 KiB
C++
67 lines
1.6 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 drop_while_view(V base, Pred pred); // explicit since C++23
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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 "test_convertible.h"
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#include "test_macros.h"
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struct View : std::ranges::view_base {
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MoveOnly mo;
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int* begin() const;
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int* end() const;
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};
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struct Pred {
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bool copied = false;
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bool moved = false;
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constexpr Pred() = default;
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constexpr Pred(Pred&&) : moved(true) {}
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constexpr Pred(const Pred&) : copied(true) {}
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bool operator()(int) const;
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};
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// SFINAE tests.
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#if TEST_STD_VER >= 23
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static_assert(!test_convertible<std::ranges::drop_while_view<View, Pred>, View, Pred>(),
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"This constructor must be explicit");
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#else
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static_assert( test_convertible<std::ranges::drop_while_view<View, Pred>, View, Pred>(),
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"This constructor must not be explicit");
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#endif // TEST_STD_VER >= 23
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constexpr bool test() {
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{
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std::ranges::drop_while_view<View, Pred> dwv{View{{}, MoveOnly{5}}, Pred{}};
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assert(dwv.pred().moved);
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assert(!dwv.pred().copied);
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assert(std::move(dwv).base().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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