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//===----------------------------------------------------------------------===//
// 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, c++20
// E& error() & noexcept;
// const E& error() const & noexcept;
// E&& error() && noexcept;
// const E&& error() const && noexcept;
#include <cassert>
#include <concepts>
#include <expected>
#include <utility>
template <class T>
concept ErrorNoexcept =
requires(T&& t) {
{ std::forward<T>(t).error() } noexcept;
};
static_assert(!ErrorNoexcept<int>);
static_assert(ErrorNoexcept<std::bad_expected_access<int>&>);
static_assert(ErrorNoexcept<std::bad_expected_access<int> const&>);
static_assert(ErrorNoexcept<std::bad_expected_access<int>&&>);
static_assert(ErrorNoexcept<std::bad_expected_access<int> const&&>);
void test() {
// &
{
std::bad_expected_access<int> e(5);
decltype(auto) i = e.error();
static_assert(std::same_as<decltype(i), int&>);
assert(i == 5);
}
// const &
{
const std::bad_expected_access<int> e(5);
decltype(auto) i = e.error();
static_assert(std::same_as<decltype(i), const int&>);
assert(i == 5);
}
// &&
{
std::bad_expected_access<int> e(5);
decltype(auto) i = std::move(e).error();
static_assert(std::same_as<decltype(i), int&&>);
assert(i == 5);
}
// const &&
{
const std::bad_expected_access<int> e(5);
decltype(auto) i = std::move(e).error();
static_assert(std::same_as<decltype(i), const int&&>);
assert(i == 5);
}
}
int main(int, char**) {
test();
return 0;
}
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