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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, c++23
// <functional>
// class reference_wrapper
// [refwrap.comparisons], comparisons
// friend constexpr bool operator==(reference_wrapper, reference_wrapper<const T>); // Since C++26
#include <cassert>
#include <concepts>
#include <functional>
#include "test_comparisons.h"
#include "test_macros.h"
#include "helper_concepts.h"
#include "helper_types.h"
// Test SFINAE.
static_assert(std::equality_comparable_with<std::reference_wrapper<EqualityComparable>,
std::reference_wrapper<const EqualityComparable>>);
static_assert(!std::equality_comparable_with<std::reference_wrapper<EqualityComparable>,
std::reference_wrapper<const NonComparable>>);
// Test equality.
template <typename T>
constexpr void test() {
T i{92};
T j{84};
std::reference_wrapper<T> rw1{i};
std::reference_wrapper<T> rw3{j};
std::reference_wrapper<const T> crw1{i};
std::reference_wrapper<const T> crw3{j};
AssertEqualityReturnBool<decltype(rw1), decltype(crw1)>();
assert(testEquality(rw1, crw1, true));
assert(testEquality(rw1, crw3, false));
}
constexpr bool test() {
test<int>();
test<EqualityComparable>();
return true;
}
int main(int, char**) {
test();
static_assert(test());
return 0;
}
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