62 lines · cpp
1//===----------------------------------------------------------------------===//2//3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.4// See https://llvm.org/LICENSE.txt for license information.5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception6//7//===----------------------------------------------------------------------===//8 9// REQUIRES: std-at-least-c++2610 11// <functional>12 13// class reference_wrapper14 15// [refwrap.comparisons], comparisons16 17// friend constexpr bool operator==(reference_wrapper, const T&); // Since C++2618 19#include <cassert>20#include <concepts>21#include <functional>22 23#include "test_comparisons.h"24#include "test_macros.h"25 26// Test SFINAE.27 28static_assert(HasOperatorEqual<std::reference_wrapper<EqualityComparable>>);29static_assert(HasOperatorEqual<std::reference_wrapper<EqualityComparable>, int>);30 31static_assert(!HasOperatorEqual<std::reference_wrapper<NonComparable>>);32static_assert(!HasOperatorEqual<std::reference_wrapper<NonComparable>, int>);33 34// Test equality.35 36template <typename T>37constexpr void test() {38 T i{92};39 T j{84};40 41 std::reference_wrapper<T> rw1{i};42 43 // refwrap, const&44 AssertEqualityReturnBool<decltype(rw1), decltype(i)>();45 assert(testEquality(rw1, i, true));46 assert(testEquality(rw1, j, false));47}48 49constexpr bool test() {50 test<int>();51 test<EqualityComparable>();52 53 return true;54}55 56int main(int, char**) {57 test();58 static_assert(test());59 60 return 0;61}62