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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>
// optional<T>& operator=(const optional<T>& rhs);
#include <experimental/optional>
#include <type_traits>
#include <cassert>
#if _LIBCPP_STD_VER > 11
using std::experimental::optional;
struct X
{
static bool throw_now;
X() = default;
X(const X&)
{
if (throw_now)
throw 6;
}
};
bool X::throw_now = false;
#endif // _LIBCPP_STD_VER > 11
int main()
{
#if _LIBCPP_STD_VER > 11
{
optional<int> opt;
constexpr optional<int> opt2;
opt = opt2;
static_assert(static_cast<bool>(opt2) == false, "");
assert(static_cast<bool>(opt) == static_cast<bool>(opt2));
}
{
optional<int> opt;
constexpr optional<int> opt2(2);
opt = opt2;
static_assert(static_cast<bool>(opt2) == true, "");
static_assert(*opt2 == 2, "");
assert(static_cast<bool>(opt) == static_cast<bool>(opt2));
assert(*opt == *opt2);
}
{
optional<int> opt(3);
constexpr optional<int> opt2;
opt = opt2;
static_assert(static_cast<bool>(opt2) == false, "");
assert(static_cast<bool>(opt) == static_cast<bool>(opt2));
}
{
optional<int> opt(3);
constexpr optional<int> opt2(2);
opt = opt2;
static_assert(static_cast<bool>(opt2) == true, "");
static_assert(*opt2 == 2, "");
assert(static_cast<bool>(opt) == static_cast<bool>(opt2));
assert(*opt == *opt2);
}
{
optional<X> opt;
optional<X> opt2(X{});
assert(static_cast<bool>(opt2) == true);
try
{
X::throw_now = true;
opt = opt2;
assert(false);
}
catch (int i)
{
assert(i == 6);
assert(static_cast<bool>(opt) == false);
}
}
#endif // _LIBCPP_STD_VER > 11
}
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