//===----------------------------------------------------------------------===//
//
// 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>
// T& optional<T>::value();
#include <experimental/optional>
#include <type_traits>
#include <cassert>
#if _LIBCPP_STD_VER > 11
using std::experimental::optional;
using std::experimental::bad_optional_access;
struct X
{
X() = default;
X(const X&) = delete;
constexpr int test() const {return 3;}
int test() {return 4;}
};
#endif // _LIBCPP_STD_VER > 11
int main()
{
#if _LIBCPP_STD_VER > 11
{
optional<X> opt;
opt.emplace();
assert(opt.value().test() == 4);
}
{
optional<X> opt;
try
{
opt.value();
assert(false);
}
catch (const bad_optional_access&)
{
}
}
#endif // _LIBCPP_STD_VER > 11
}