{

int val;

explicit Value(int v) : val(v) {}

{

Tref v1 (1), v2 (2);

optional<Tref&> opt_ref0;

optional<Tref&> opt_ref1 (v1);

optional<Tval> opt_val0 (opt_ref0);

optional<Tval> opt_val1 (opt_ref1);

optional<Tval> opt_val2 (make_opt_ref(v2));

BOOST_TEST (!opt_val0);

BOOST_TEST (opt_val1);

BOOST_TEST (opt_val2);

BOOST_TEST_EQ (1, val(*opt_val1));

BOOST_TEST_EQ (2, val(*opt_val2));

BOOST_TEST (boost::addressof(*opt_val1) != boost::addressof(v1));

BOOST_TEST (boost::addressof(*opt_val2) != boost::addressof(v2));

{

Tref v1 (1), v2 (2);

optional<Tref&> opt_ref0;

optional<Tref&> opt_ref1 (v1);

optional<Tval> opt_val0;

optional<Tval> opt_val1;

optional<Tval> opt_val2;

opt_val0 = opt_ref0;

opt_val1 = opt_ref1;

opt_val2 = make_opt_ref(v2);

BOOST_TEST (!opt_val0);

BOOST_TEST (opt_val1);

BOOST_TEST (opt_val2);

BOOST_TEST_EQ (1, val(*opt_val1));

BOOST_TEST_EQ (2, val(*opt_val2));

BOOST_TEST (boost::addressof(*opt_val1) != boost::addressof(v1));

BOOST_TEST (boost::addressof(*opt_val2) != boost::addressof(v2));

{

test_construct_from_optional_ref<int, int>();

test_construct_from_optional_ref<int, int const>();

test_construct_from_optional_ref<int const, int const>();

test_construct_from_optional_ref<int const, int>();

test_construct_from_optional_ref<Value, Value>();

test_construct_from_optional_ref<Value, Value const>();

test_construct_from_optional_ref<Value const, Value const>();

test_construct_from_optional_ref<Value const, Value>();

test_assign_from_optional_ref<int, int>();

test_assign_from_optional_ref<int, int const>();

test_assign_from_optional_ref<Value, Value>();

test_assign_from_optional_ref<Value, Value const>();

return boost::report_errors();