43         optional<B> opt;  in main()  local
44         ASSERT_NOT_NOEXCEPT(std::hash<optional<B>>()(opt));  in main()
45         ASSERT_NOT_NOEXCEPT(std::hash<optional<const B>>()(opt));  in main()
50         optional<T> opt;  in main()  local
51         assert(std::hash<optional<T>>{}(opt) == nullopt_hash);  in main()
52         opt = 2;  in main()
53         assert(std::hash<optional<T>>{}(opt) == std::hash<T>{}(*opt));  in main()
57         optional<T> opt;  in main()  local
58         assert(std::hash<optional<T>>{}(opt) == nullopt_hash);  in main()
59         opt = std::string("123");  in main()
60         assert(std::hash<optional<T>>{}(opt) == std::hash<T>{}(*opt));  in main()
64         optional<T> opt;  in main()  local
65         assert(std::hash<optional<T>>{}(opt) == nullopt_hash);  in main()
66         opt = std::unique_ptr<int>(new int(3));  in main()
67         assert(std::hash<optional<T>>{}(opt) == std::hash<T>{}(*opt));  in main()