89 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// UNSUPPORTED: c++03, c++11, c++1410// <optional>11 12// template <class T, class U> constexpr bool operator==(const optional<T>& x, const U& v);13// template <class T, class U> constexpr bool operator==(const U& v, const optional<T>& x);14 15#include <optional>16 17#include "test_comparisons.h"18#include "test_macros.h"19 20#if TEST_STD_VER >= 2621 22// Test SFINAE.23 24static_assert(HasOperatorEqual<int, std::optional<int>>);25static_assert(HasOperatorEqual<int, std::optional<EqualityComparable>>);26static_assert(HasOperatorEqual<EqualityComparable, std::optional<EqualityComparable>>);27 28static_assert(!HasOperatorEqual<NonComparable, std::optional<NonComparable>>);29static_assert(!HasOperatorEqual<NonComparable, std::optional<EqualityComparable>>);30 31static_assert(HasOperatorEqual<std::optional<int>, int>);32static_assert(HasOperatorEqual<std::optional<EqualityComparable>, int>);33static_assert(HasOperatorEqual<std::optional<EqualityComparable>, EqualityComparable>);34 35static_assert(!HasOperatorEqual<std::optional<NonComparable>, NonComparable>);36static_assert(!HasOperatorEqual<std::optional<EqualityComparable>, NonComparable>);37 38#endif39 40using std::optional;41 42struct X {43 int i_;44 45 constexpr X(int i) : i_(i) {}46};47 48constexpr bool operator==(const X& lhs, const X& rhs) {49 return lhs.i_ == rhs.i_;50}51 52int main(int, char**) {53 {54 typedef X T;55 typedef optional<T> O;56 57 constexpr T val(2);58 constexpr O o1; // disengaged59 constexpr O o2{1}; // engaged60 constexpr O o3{val}; // engaged61 62 static_assert(!(o1 == T(1)), "");63 static_assert((o2 == T(1)), "");64 static_assert(!(o3 == T(1)), "");65 static_assert((o3 == T(2)), "");66 static_assert((o3 == val), "");67 68 static_assert(!(T(1) == o1), "");69 static_assert((T(1) == o2), "");70 static_assert(!(T(1) == o3), "");71 static_assert((T(2) == o3), "");72 static_assert((val == o3), "");73 }74 {75 using O = optional<int>;76 constexpr O o1(42);77 static_assert(o1 == 42l, "");78 static_assert(!(101l == o1), "");79 }80 {81 using O = optional<const int>;82 constexpr O o1(42);83 static_assert(o1 == 42, "");84 static_assert(!(101 == o1), "");85 }86 87 return 0;88}89