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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.
//
//===----------------------------------------------------------------------===//
// <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 <experimental/optional>
int main()
{
#if _LIBCPP_STD_VER > 11
using std::experimental::optional;
using std::experimental::nullopt_t;
using std::experimental::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), "");
}
#endif
}
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