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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 U& v);
// template <class T, class U> constexpr bool operator!=(const U& v, const optional<T>& x);
#include <optional>
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 T val(2);
constexpr O o1; // disengaged
constexpr O o2{1}; // engaged
constexpr O o3{val}; // engaged
static_assert((o1 != T(1)), "");
static_assert(!(o2 != T(1)), "");
static_assert((o3 != T(1)), "");
static_assert(!(o3 != T(2)), "");
static_assert(!(o3 != val), "");
static_assert((T(1) != o1), "");
static_assert(!(T(1) != o2), "");
static_assert((T(1) != o3), "");
static_assert(!(T(2) != o3), "");
static_assert(!(val != o3), "");
}
{
using O = optional<int>;
constexpr O o1(42);
static_assert(o1 != 101l, "");
static_assert(!(42l != o1), "");
}
{
using O = optional<const int>;
constexpr O o1(42);
static_assert(o1 != 101, "");
static_assert(!(42 != o1), "");
}
}
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