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//===----------------------------------------------------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is dual licensed under the MIT and the University of Illinois Open
// Source Licenses. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
// UNSUPPORTED: c++98, c++03, c++11, c++14
// <optional>
// template <class T, class U> constexpr bool operator==(const optional<T>& x, const optional<U>& y);
#include <optional>
#include <type_traits>
#include <cassert>
using std::optional;
struct X {
int i_;
constexpr X(int i) : i_(i) {}
};
constexpr bool operator==(const X& lhs, const X& rhs) {
return lhs.i_ == rhs.i_;
}
int main() {
{
typedef X T;
typedef optional<T> O;
constexpr O o1; // disengaged
constexpr O o2; // disengaged
constexpr O o3{1}; // engaged
constexpr O o4{2}; // engaged
constexpr O o5{1}; // engaged
static_assert(o1 == o1, "");
static_assert(o1 == o2, "");
static_assert(!(o1 == o3), "");
static_assert(!(o1 == o4), "");
static_assert(!(o1 == o5), "");
static_assert(o2 == o1, "");
static_assert(o2 == o2, "");
static_assert(!(o2 == o3), "");
static_assert(!(o2 == o4), "");
static_assert(!(o2 == o5), "");
static_assert(!(o3 == o1), "");
static_assert(!(o3 == o2), "");
static_assert(o3 == o3, "");
static_assert(!(o3 == o4), "");
static_assert(o3 == o5, "");
static_assert(!(o4 == o1), "");
static_assert(!(o4 == o2), "");
static_assert(!(o4 == o3), "");
static_assert(o4 == o4, "");
static_assert(!(o4 == o5), "");
static_assert(!(o5 == o1), "");
static_assert(!(o5 == o2), "");
static_assert(o5 == o3, "");
static_assert(!(o5 == o4), "");
static_assert(o5 == o5, "");
}
{
using O1 = optional<int>;
using O2 = optional<long>;
constexpr O1 o1(42);
static_assert(o1 == O2(42), "");
static_assert(!(O2(101) == o1), "");
}
{
using O1 = optional<int>;
using O2 = optional<const int>;
constexpr O1 o1(42);
static_assert(o1 == O2(42), "");
static_assert(!(O2(101) == o1), "");
}
}
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