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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 U>
// optional(optional<U>&& rhs);
#include <optional>
#include <type_traits>
#include <memory>
#include <cassert>
#include "test_macros.h"
using std::optional;
template <class T, class U>
void
test(optional<U>&& rhs, bool is_going_to_throw = false)
{
bool rhs_engaged = static_cast<bool>(rhs);
#ifndef TEST_HAS_NO_EXCEPTIONS
try
{
optional<T> lhs = std::move(rhs);
assert(is_going_to_throw == false);
assert(static_cast<bool>(lhs) == rhs_engaged);
}
catch (int i)
{
assert(i == 6);
}
#else
if (is_going_to_throw) return;
optional<T> lhs = std::move(rhs);
assert(static_cast<bool>(lhs) == rhs_engaged);
#endif
}
class X
{
int i_;
public:
X(int i) : i_(i) {}
X(X&& x) : i_(std::exchange(x.i_, 0)) {}
~X() {i_ = 0;}
friend bool operator==(const X& x, const X& y) {return x.i_ == y.i_;}
};
int count = 0;
struct Z
{
Z(int) { TEST_THROW(6); }
};
int main()
{
{
optional<short> rhs;
test<int>(std::move(rhs));
}
{
optional<short> rhs(short{3});
test<int>(std::move(rhs));
}
{
optional<int> rhs;
test<X>(std::move(rhs));
}
{
optional<int> rhs(3);
test<X>(std::move(rhs));
}
{
optional<int> rhs;
test<Z>(std::move(rhs));
}
{
optional<int> rhs(3);
test<Z>(std::move(rhs), true);
}
static_assert(!(std::is_constructible<optional<X>, optional<Z>>::value), "");
}
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