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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> constexpr bool operator==(const optional<T>& x, nullopt_t) noexcept;
// template <class T> constexpr bool operator==(nullopt_t, const optional<T>& x) noexcept;
#include <optional>
int main()
{
using std::optional;
using std::nullopt_t;
using std::nullopt;
{
typedef int T;
typedef optional<T> O;
constexpr O o1; // disengaged
constexpr O o2{1}; // engaged
static_assert ( (nullopt == o1), "" );
static_assert ( !(nullopt == o2), "" );
static_assert ( (o1 == nullopt), "" );
static_assert ( !(o2 == nullopt), "" );
static_assert (noexcept(nullopt == o1), "");
static_assert (noexcept(o1 == nullopt), "");
}
}
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