065dc485bd
This patch implements https://www.open-std.org/jtc1/sc22/wg21/docs/papers/2021/p2443r1.html (`views::chunk_by`). Reviewed By: #libc, var-const Differential Revision: https://reviews.llvm.org/D144767
61 lines
1.4 KiB
C++
61 lines
1.4 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, c++20
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// <ranges>
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// constexpr Pred const& pred() const;
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#include <ranges>
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#include <cassert>
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#include <concepts>
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struct Range : std::ranges::view_base {
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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 operator()(int, int) const;
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int value;
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};
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constexpr bool test() {
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{
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Pred pred{42};
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std::ranges::chunk_by_view<Range, Pred> const view(Range{}, pred);
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std::same_as<Pred const&> decltype(auto) result = view.pred();
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assert(result.value == 42);
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// Make sure we're really holding a reference to something inside the view
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assert(&result == &view.pred());
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}
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// Same, but calling on a non-const view
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{
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Pred pred{42};
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std::ranges::chunk_by_view<Range, Pred> view(Range{}, pred);
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std::same_as<Pred const&> decltype(auto) result = view.pred();
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assert(result.value == 42);
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// Make sure we're really holding a reference to something inside the view
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assert(&result == &view.pred());
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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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