351 class optional : private OptionalBase<T>  class
400   constexpr optional() noexcept : OptionalBase<T>()  {};  in optional()  function in std::experimental::optional
401   constexpr optional(nullopt_t) noexcept : OptionalBase<T>() {};  in optional()  function in std::experimental::optional
403   optional(const optional& rhs)  in optional()  function in std::experimental::optional
412   optional(optional&& rhs) noexcept(is_nothrow_move_constructible<T>::value)  in optional()  function in std::experimental::optional
421   constexpr optional(const T& v) : OptionalBase<T>(v) {}  in optional()  function in std::experimental::optional
423   constexpr optional(T&& v) : OptionalBase<T>(constexpr_move(v)) {}  in optional()  function in std::experimental::optional
426   explicit constexpr optional(in_place_t, Args&&... args)  in optional()  function in std::experimental::optional
430 …OPTIONAL_CONSTEXPR_INIT_LIST explicit optional(in_place_t, std::initializer_list<U> il, Args&&... …  in optional()  function in std::experimental::optional
604 class optional<T&>  class
613   constexpr optional() noexcept : ref(nullptr) {}  in optional()  function in std::experimental::optional
615   constexpr optional(nullopt_t) noexcept : ref(nullptr) {}  in optional()  function in std::experimental::optional
617   constexpr optional(T& v) noexcept : ref(detail_::static_addressof(v)) {}  in optional()  function in std::experimental::optional
621   constexpr optional(const optional& rhs) noexcept : ref(rhs.ref) {}  in optional()  function in std::experimental::optional
623   explicit constexpr optional(in_place_t, T& v) noexcept : ref(detail_::static_addressof(v)) {}  in optional()  function in std::experimental::optional
704 class optional<T&&>  class