diff options
Diffstat (limited to 'libcxx/include')
| -rw-r--r-- | libcxx/include/type_traits | 63 |
1 files changed, 51 insertions, 12 deletions
diff --git a/libcxx/include/type_traits b/libcxx/include/type_traits index b7adfebceeb..3b80a9efa5d 100644 --- a/libcxx/include/type_traits +++ b/libcxx/include/type_traits @@ -957,6 +957,38 @@ template <class _Tp> _LIBCPP_CONSTEXPR bool is_compound_v = is_compound<_Tp>::value; #endif + +// __is_referenceable [defns.referenceable] +template <class _Tp> struct __is_referenceable + : public std::integral_constant<bool, is_object<_Tp>::value || is_reference<_Tp>::value> {}; + +#ifndef _LIBCPP_HAS_NO_VARIADICS +template <class _Ret, class... _Args> +struct __is_referenceable<_Ret(_Args...)> : public std::true_type {}; + +template <class _Ret, class... _Args> +struct __is_referenceable<_Ret(_Args..., ...)> : public std::true_type {}; +#else +template <class _Ret> +struct __is_referenceable<_Ret()> : public std::true_type {}; +template <class _Ret, class _A0> +struct __is_referenceable<_Ret(_A0)> : public std::true_type {}; +template <class _Ret, class _A0, class _A1> +struct __is_referenceable<_Ret(_A0, _A1)> : public std::true_type {}; +template <class _Ret, class _A0, class _A1, class _A2> +struct __is_referenceable<_Ret(_A0, _A1, _A2)> : public std::true_type {}; + +template <class _Ret> +struct __is_referenceable<_Ret(...)> : public std::true_type {}; +template <class _Ret, class _A0> +struct __is_referenceable<_Ret(_A0, ...)> : public std::true_type {}; +template <class _Ret, class _A0, class _A1> +struct __is_referenceable<_Ret(_A0, _A1, ...)> : public std::true_type {}; +template <class _Ret, class _A0, class _A1, class _A2> +struct __is_referenceable<_Ret(_A0, _A1, _A2, ...)> : public std::true_type {}; +#endif + + // add_const template <class _Tp, bool = is_reference<_Tp>::value || @@ -1014,12 +1046,11 @@ template <class _Tp> using remove_reference_t = typename remove_reference<_Tp>:: // add_lvalue_reference -template <class _Tp> struct _LIBCPP_TYPE_VIS_ONLY add_lvalue_reference {typedef _Tp& type;}; -template <class _Tp> struct _LIBCPP_TYPE_VIS_ONLY add_lvalue_reference<_Tp&> {typedef _Tp& type;}; // for older compiler -template <> struct _LIBCPP_TYPE_VIS_ONLY add_lvalue_reference<void> {typedef void type;}; -template <> struct _LIBCPP_TYPE_VIS_ONLY add_lvalue_reference<const void> {typedef const void type;}; -template <> struct _LIBCPP_TYPE_VIS_ONLY add_lvalue_reference<volatile void> {typedef volatile void type;}; -template <> struct _LIBCPP_TYPE_VIS_ONLY add_lvalue_reference<const volatile void> {typedef const volatile void type;}; +template <class _Tp, bool = __is_referenceable<_Tp>::value> struct __add_lvalue_reference_impl { typedef _Tp type; }; +template <class _Tp > struct __add_lvalue_reference_impl<_Tp, true> { typedef _Tp& type; }; + +template <class _Tp> struct _LIBCPP_TYPE_VIS_ONLY add_lvalue_reference +{typedef typename __add_lvalue_reference_impl<_Tp>::type type;}; #if _LIBCPP_STD_VER > 11 template <class _Tp> using add_lvalue_reference_t = typename add_lvalue_reference<_Tp>::type; @@ -1027,11 +1058,11 @@ template <class _Tp> using add_lvalue_reference_t = typename add_lvalue_referenc #ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES -template <class _Tp> struct _LIBCPP_TYPE_VIS_ONLY add_rvalue_reference {typedef _Tp&& type;}; -template <> struct _LIBCPP_TYPE_VIS_ONLY add_rvalue_reference<void> {typedef void type;}; -template <> struct _LIBCPP_TYPE_VIS_ONLY add_rvalue_reference<const void> {typedef const void type;}; -template <> struct _LIBCPP_TYPE_VIS_ONLY add_rvalue_reference<volatile void> {typedef volatile void type;}; -template <> struct _LIBCPP_TYPE_VIS_ONLY add_rvalue_reference<const volatile void> {typedef const volatile void type;}; +template <class _Tp, bool = __is_referenceable<_Tp>::value> struct __add_rvalue_reference_impl { typedef _Tp type; }; +template <class _Tp > struct __add_rvalue_reference_impl<_Tp, true> { typedef _Tp&& type; }; + +template <class _Tp> struct _LIBCPP_TYPE_VIS_ONLY add_rvalue_reference +{typedef typename __add_rvalue_reference_impl<_Tp>::type type;}; #if _LIBCPP_STD_VER > 11 template <class _Tp> using add_rvalue_reference_t = typename add_rvalue_reference<_Tp>::type; @@ -1072,8 +1103,16 @@ template <class _Tp> using remove_pointer_t = typename remove_pointer<_Tp>::type // add_pointer -template <class _Tp> struct _LIBCPP_TYPE_VIS_ONLY add_pointer +template <class _Tp, + bool = __is_referenceable<_Tp>::value || + is_same<typename remove_cv<_Tp>::type, void>::value> +struct __add_pointer_impl {typedef typename remove_reference<_Tp>::type* type;}; +template <class _Tp> struct __add_pointer_impl<_Tp, false> + {typedef _Tp type;}; + +template <class _Tp> struct _LIBCPP_TYPE_VIS_ONLY add_pointer + {typedef typename __add_pointer_impl<_Tp>::type type;}; #if _LIBCPP_STD_VER > 11 template <class _Tp> using add_pointer_t = typename add_pointer<_Tp>::type; |
