e356f681f6
Implement `std::expected` https://www.open-std.org/jtc1/sc22/wg21/docs/papers/2022/p0323r12.html Added tests Differential Revision: https://reviews.llvm.org/D124516 address comment
58 lines
1.3 KiB
C++
58 lines
1.3 KiB
C++
//===----------------------------------------------------------------------===//
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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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// constexpr const T* operator->() const noexcept;
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// constexpr T* operator->() noexcept;
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#include <cassert>
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#include <concepts>
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#include <expected>
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#include <type_traits>
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#include <utility>
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#include "test_macros.h"
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// Test noexcept
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template <class T>
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concept ArrowNoexcept =
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requires(T t) {
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{ t.operator->() } noexcept;
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};
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static_assert(!ArrowNoexcept<int>);
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static_assert(ArrowNoexcept<std::expected<int, int>>);
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static_assert(ArrowNoexcept<const std::expected<int, int>>);
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constexpr bool test() {
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// const
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{
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const std::expected<int, int> e(5);
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std::same_as<const int*> decltype(auto) x = e.operator->();
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assert(x == &(e.value()));
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assert(*x == 5);
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}
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// non-const
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{
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std::expected<int, int> e(5);
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std::same_as<int*> decltype(auto) x = e.operator->();
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assert(x == &(e.value()));
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assert(*x == 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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