25 using std::optional;
30     const optional<T> orig(std::forward<InitArgs>(args)...);  in test()
31     optional<T> rhs(orig);  in test()
33     optional<T> lhs = std::move(rhs);  in test()
43     const optional<T> orig(std::forward<InitArgs>(args)...);  in constexpr_test()
44     optional<T> rhs(orig);  in constexpr_test()
45     optional<T> lhs = std::move(rhs);  in constexpr_test()
59     optional<Z> rhs(std::move(z));  in test_throwing_ctor()
62         optional<Z> lhs(std::move(rhs));  in test_throwing_ctor()
76     optional<T> rhs(std::forward<InitArgs>(args)...);  in test_ref()
78     optional<T> lhs = std::move(rhs);  in test_ref()
142         static_assert(!std::is_copy_constructible<std::optional<T&&>>::value, "");  in test_reference_extension()
143         static_assert(!std::is_copy_constructible<std::optional<T const&&>>::value, "");  in test_reference_extension()
157         optional<const int> o(42);  in main()
158         optional<const int> o2(std::move(o));  in main()
164         optional<T> rhs;  in main()
166         const optional<T> lhs(std::move(rhs));  in main()
175         optional<T> rhs(42);  in main()
179         const optional<T> lhs(std::move(rhs));  in main()
207         static_assert(!std::is_nothrow_move_constructible<optional<ThrowsMove>>::value, "");  in main()
213         static_assert(std::is_nothrow_move_constructible<optional<NoThrowMove>>::value, "");  in main()
219     constexpr std::optional<int> o1{4};  in main()
220     constexpr std::optional<int> o2 = std::move(o1);  in main()