// TR1 type_traits -*- C++ -*- // Copyright (C) 2004-2020 Free Software Foundation, Inc. // // This file is part of the GNU ISO C++ Library. This library is free // software; you can redistribute it and/or modify it under the // terms of the GNU General Public License as published by the // Free Software Foundation; either version 3, or (at your option) // any later version. // This library is distributed in the hope that it will be useful, // but WITHOUT ANY WARRANTY; without even the implied warranty of // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the // GNU General Public License for more details. // Under Section 7 of GPL version 3, you are granted additional // permissions described in the GCC Runtime Library Exception, version // 3.1, as published by the Free Software Foundation. // You should have received a copy of the GNU General Public License and // a copy of the GCC Runtime Library Exception along with this program; // see the files COPYING3 and COPYING.RUNTIME respectively. If not, see // <http://www.gnu.org/licenses/>. /** @file tr1/type_traits * This is a TR1 C++ Library header. */ #ifndef _GLIBCXX_TR1_TYPE_TRAITS #define _GLIBCXX_TR1_TYPE_TRAITS 1 #pragma GCC system_header #include <bits/c++config.h> namespace std _GLIBCXX_VISIBILITY(default) { _GLIBCXX_BEGIN_NAMESPACE_VERSION namespace tr1 { /** * @addtogroup metaprogramming * @{ */ struct __sfinae_types { typedef char __one; typedef struct { char __arr[2]; } __two; }; #define _DEFINE_SPEC_0_HELPER \ template<> #define _DEFINE_SPEC_1_HELPER \ template<typename _Tp> #define _DEFINE_SPEC_2_HELPER \ template<typename _Tp, typename _Cp> #define _DEFINE_SPEC(_Order, _Trait, _Type, _Value) \ _DEFINE_SPEC_##_Order##_HELPER \ struct _Trait<_Type> \ : public integral_constant<bool, _Value> { }; // helper classes [4.3]. /// integral_constant template<typename _Tp, _Tp __v> struct integral_constant { static const _Tp value = __v; typedef _Tp value_type; typedef integral_constant<_Tp, __v> type; }; /// typedef for true_type typedef integral_constant<bool, true> true_type; /// typedef for false_type typedef integral_constant<bool, false> false_type; template<typename _Tp, _Tp __v> const _Tp integral_constant<_Tp, __v>::value; /// remove_cv template<typename> struct remove_cv; template<typename> struct __is_void_helper : public false_type { }; _DEFINE_SPEC(0, __is_void_helper, void, true) // primary type categories [4.5.1]. /// is_void template<typename _Tp> struct is_void : public integral_constant<bool, (__is_void_helper<typename remove_cv<_Tp>::type>::value)> { }; template<typename> struct __is_integral_helper : public false_type { }; _DEFINE_SPEC(0, __is_integral_helper, bool, true) _DEFINE_SPEC(0, __is_integral_helper, char, true) _DEFINE_SPEC(0, __is_integral_helper, signed char, true) _DEFINE_SPEC(0, __is_integral_helper, unsigned char, true) #ifdef _GLIBCXX_USE_WCHAR_T _DEFINE_SPEC(0, __is_integral_helper, wchar_t, true) #endif _DEFINE_SPEC(0, __is_integral_helper, short, true) _DEFINE_SPEC(0, __is_integral_helper, unsigned short, true) _DEFINE_SPEC(0, __is_integral_helper, int, true) _DEFINE_SPEC(0, __is_integral_helper, unsigned int, true) _DEFINE_SPEC(0, __is_integral_helper, long, true) _DEFINE_SPEC(0, __is_integral_helper, unsigned long, true) _DEFINE_SPEC(0, __is_integral_helper, long long, true) _DEFINE_SPEC(0, __is_integral_helper, unsigned long long, true) /// is_integral template<typename _Tp> struct is_integral : public integral_constant<bool, (__is_integral_helper<typename remove_cv<_Tp>::type>::value)> { }; template<typename> struct __is_floating_point_helper : public false_type { }; _DEFINE_SPEC(0, __is_floating_point_helper, float, true) _DEFINE_SPEC(0, __is_floating_point_helper, double, true) _DEFINE_SPEC(0, __is_floating_point_helper, long double, true) /// is_floating_point template<typename _Tp> struct is_floating_point : public integral_constant<bool, (__is_floating_point_helper<typename remove_cv<_Tp>::type>::value)> { }; /// is_array template<typename> struct is_array : public false_type { }; template<typename _Tp, std::size_t _Size> struct is_array<_Tp[_Size]> : public true_type { }; template<typename _Tp> struct is_array<_Tp[]> : public true_type { }; template<typename> struct __is_pointer_helper : public false_type { }; _DEFINE_SPEC(1, __is_pointer_helper, _Tp*, true) /// is_pointer template<typename _Tp> struct is_pointer : public integral_constant<bool, (__is_pointer_helper<typename remove_cv<_Tp>::type>::value)> { }; /// is_reference template<typename _Tp> struct is_reference; /// is_function template<typename _Tp> struct is_function; template<typename> struct __is_member_object_pointer_helper : public false_type { }; _DEFINE_SPEC(2, __is_member_object_pointer_helper, _Tp _Cp::*, !is_function<_Tp>::value) /// is_member_object_pointer template<typename _Tp> struct is_member_object_pointer : public integral_constant<bool, (__is_member_object_pointer_helper< typename remove_cv<_Tp>::type>::value)> { }; template<typename> struct __is_member_function_pointer_helper : public false_type { }; _DEFINE_SPEC(2, __is_member_function_pointer_helper, _Tp _Cp::*, is_function<_Tp>::value) /// is_member_function_pointer template<typename _Tp> struct is_member_function_pointer : public integral_constant<bool, (__is_member_function_pointer_helper< typename remove_cv<_Tp>::type>::value)> { }; /// is_enum template<typename _Tp> struct is_enum : public integral_constant<bool, __is_enum(_Tp)> { }; /// is_union template<typename _Tp> struct is_union : public integral_constant<bool, __is_union(_Tp)> { }; /// is_class template<typename _Tp> struct is_class : public integral_constant<bool, __is_class(_Tp)> { }; /// is_function template<typename> struct is_function : public false_type { }; template<typename _Res, typename... _ArgTypes> struct is_function<_Res(_ArgTypes...)> : public true_type { }; template<typename _Res, typename... _ArgTypes> struct is_function<_Res(_ArgTypes......)> : public true_type { }; template<typename _Res, typename... _ArgTypes> struct is_function<_Res(_ArgTypes...) const> : public true_type { }; template<typename _Res, typename... _ArgTypes> struct is_function<_Res(_ArgTypes......) const> : public true_type { }; template<typename _Res, typename... _ArgTypes> struct is_function<_Res(_ArgTypes...) volatile> : public true_type { }; template<typename _Res, typename... _ArgTypes> struct is_function<_Res(_ArgTypes......) volatile> : public true_type { }; template<typename _Res, typename... _ArgTypes> struct is_function<_Res(_ArgTypes...) const volatile> : public true_type { }; template<typename _Res, typename... _ArgTypes> struct is_function<_Res(_ArgTypes......) const volatile> : public true_type { }; // composite type traits [4.5.2]. /// is_arithmetic template<typename _Tp> struct is_arithmetic : public integral_constant<bool, (is_integral<_Tp>::value || is_floating_point<_Tp>::value)> { }; /// is_fundamental template<typename _Tp> struct is_fundamental : public integral_constant<bool, (is_arithmetic<_Tp>::value || is_void<_Tp>::value)> { }; /// is_object template<typename _Tp> struct is_object : public integral_constant<bool, !(is_function<_Tp>::value || is_reference<_Tp>::value || is_void<_Tp>::value)> { }; /// is_member_pointer template<typename _Tp> struct is_member_pointer; /// is_scalar template<typename _Tp> struct is_scalar : public integral_constant<bool, (is_arithmetic<_Tp>::value || is_enum<_Tp>::value || is_pointer<_Tp>::value || is_member_pointer<_Tp>::value)> { }; /// is_compound template<typename _Tp> struct is_compound : public integral_constant<bool, !is_fundamental<_Tp>::value> { }; /// is_member_pointer template<typename _Tp> struct __is_member_pointer_helper : public false_type { }; _DEFINE_SPEC(2, __is_member_pointer_helper, _Tp _Cp::*, true) template<typename _Tp> struct is_member_pointer : public integral_constant<bool, (__is_member_pointer_helper< typename remove_cv<_Tp>::type>::value)> { }; // type properties [4.5.3]. /// is_const template<typename> struct is_const : public false_type { }; template<typename _Tp> struct is_const<_Tp const> : public true_type { }; /// is_volatile template<typename> struct is_volatile : public false_type { }; template<typename _Tp> struct is_volatile<_Tp volatile> : public true_type { }; /// is_empty template<typename _Tp> struct is_empty : public integral_constant<bool, __is_empty(_Tp)> { }; /// is_polymorphic template<typename _Tp> struct is_polymorphic : public integral_constant<bool, __is_polymorphic(_Tp)> { }; /// is_abstract template<typename _Tp> struct is_abstract : public integral_constant<bool, __is_abstract(_Tp)> { }; /// has_virtual_destructor template<typename _Tp> struct has_virtual_destructor : public integral_constant<bool, __has_virtual_destructor(_Tp)> { }; /// alignment_of template<typename _Tp> struct alignment_of : public integral_constant<std::size_t, __alignof__(_Tp)> { }; /// rank template<typename> struct rank : public integral_constant<std::size_t, 0> { }; template<typename _Tp, std::size_t _Size> struct rank<_Tp[_Size]> : public integral_constant<std::size_t, 1 + rank<_Tp>::value> { }; template<typename _Tp> struct rank<_Tp[]> : public integral_constant<std::size_t, 1 + rank<_Tp>::value> { }; /// extent template<typename, unsigned _Uint = 0> struct extent : public integral_constant<std::size_t, 0> { }; template<typename _Tp, unsigned _Uint, std::size_t _Size> struct extent<_Tp[_Size], _Uint> : public integral_constant<std::size_t, _Uint == 0 ? _Size : extent<_Tp, _Uint - 1>::value> { }; template<typename _Tp, unsigned _Uint> struct extent<_Tp[], _Uint> : public integral_constant<std::size_t, _Uint == 0 ? 0 : extent<_Tp, _Uint - 1>::value> { }; // relationships between types [4.6]. /// is_same template<typename, typename> struct is_same : public false_type { }; template<typename _Tp> struct is_same<_Tp, _Tp> : public true_type { }; // const-volatile modifications [4.7.1]. /// remove_const template<typename _Tp> struct remove_const { typedef _Tp type; }; template<typename _Tp> struct remove_const<_Tp const> { typedef _Tp type; }; /// remove_volatile template<typename _Tp> struct remove_volatile { typedef _Tp type; }; template<typename _Tp> struct remove_volatile<_Tp volatile> { typedef _Tp type; }; /// remove_cv template<typename _Tp> struct remove_cv { typedef typename remove_const<typename remove_volatile<_Tp>::type>::type type; }; /// add_const template<typename _Tp> struct add_const { typedef _Tp const type; }; /// add_volatile template<typename _Tp> struct add_volatile { typedef _Tp volatile type; }; /// add_cv template<typename _Tp> struct add_cv { typedef typename add_const<typename add_volatile<_Tp>::type>::type type; }; // array modifications [4.7.3]. /// remove_extent template<typename _Tp> struct remove_extent { typedef _Tp type; }; template<typename _Tp, std::size_t _Size> struct remove_extent<_Tp[_Size]> { typedef _Tp type; }; template<typename _Tp> struct remove_extent<_Tp[]> { typedef _Tp type; }; /// remove_all_extents template<typename _Tp> struct remove_all_extents { typedef _Tp type; }; template<typename _Tp, std::size_t _Size> struct remove_all_extents<_Tp[_Size]> { typedef typename remove_all_extents<_Tp>::type type; }; template<typename _Tp> struct remove_all_extents<_Tp[]> { typedef typename remove_all_extents<_Tp>::type type; }; // pointer modifications [4.7.4]. template<typename _Tp, typename> struct __remove_pointer_helper { typedef _Tp type; }; template<typename _Tp, typename _Up> struct __remove_pointer_helper<_Tp, _Up*> { typedef _Up type; }; /// remove_pointer template<typename _Tp> struct remove_pointer : public __remove_pointer_helper<_Tp, typename remove_cv<_Tp>::type> { }; template<typename> struct remove_reference; /// add_pointer template<typename _Tp> struct add_pointer { typedef typename remove_reference<_Tp>::type* type; }; template<typename> struct is_reference : public false_type { }; template<typename _Tp> struct is_reference<_Tp&> : public true_type { }; template<typename _Tp> struct is_pod : public integral_constant<bool, __is_pod(_Tp) || is_void<_Tp>::value> { }; template<typename _Tp> struct has_trivial_constructor : public integral_constant<bool, is_pod<_Tp>::value> { }; template<typename _Tp> struct has_trivial_copy : public integral_constant<bool, is_pod<_Tp>::value> { }; template<typename _Tp> struct has_trivial_assign : public integral_constant<bool, is_pod<_Tp>::value> { }; template<typename _Tp> struct has_trivial_destructor : public integral_constant<bool, is_pod<_Tp>::value> { }; template<typename _Tp> struct has_nothrow_constructor : public integral_constant<bool, is_pod<_Tp>::value> { }; template<typename _Tp> struct has_nothrow_copy : public integral_constant<bool, is_pod<_Tp>::value> { }; template<typename _Tp> struct has_nothrow_assign : public integral_constant<bool, is_pod<_Tp>::value> { }; template<typename> struct __is_signed_helper : public false_type { }; _DEFINE_SPEC(0, __is_signed_helper, signed char, true) _DEFINE_SPEC(0, __is_signed_helper, short, true) _DEFINE_SPEC(0, __is_signed_helper, int, true) _DEFINE_SPEC(0, __is_signed_helper, long, true) _DEFINE_SPEC(0, __is_signed_helper, long long, true) template<typename _Tp> struct is_signed : public integral_constant<bool, (__is_signed_helper<typename remove_cv<_Tp>::type>::value)> { }; template<typename> struct __is_unsigned_helper : public false_type { }; _DEFINE_SPEC(0, __is_unsigned_helper, unsigned char, true) _DEFINE_SPEC(0, __is_unsigned_helper, unsigned short, true) _DEFINE_SPEC(0, __is_unsigned_helper, unsigned int, true) _DEFINE_SPEC(0, __is_unsigned_helper, unsigned long, true) _DEFINE_SPEC(0, __is_unsigned_helper, unsigned long long, true) template<typename _Tp> struct is_unsigned : public integral_constant<bool, (__is_unsigned_helper<typename remove_cv<_Tp>::type>::value)> { }; template<typename _Base, typename _Derived> struct __is_base_of_helper { typedef typename remove_cv<_Base>::type _NoCv_Base; typedef typename remove_cv<_Derived>::type _NoCv_Derived; static const bool __value = (is_same<_Base, _Derived>::value || (__is_base_of(_Base, _Derived) && !is_same<_NoCv_Base, _NoCv_Derived>::value)); }; template<typename _Base, typename _Derived> struct is_base_of : public integral_constant<bool, __is_base_of_helper<_Base, _Derived>::__value> { }; template<typename _From, typename _To> struct __is_convertible_simple : public __sfinae_types { private: static __one __test(_To); static __two __test(...); static _From __makeFrom(); public: static const bool __value = sizeof(__test(__makeFrom())) == 1; }; template<typename _Tp> struct add_reference; template<typename _Tp> struct __is_int_or_cref { typedef typename remove_reference<_Tp>::type __rr_Tp; static const bool __value = (is_integral<_Tp>::value || (is_integral<__rr_Tp>::value && is_const<__rr_Tp>::value && !is_volatile<__rr_Tp>::value)); }; template<typename _From, typename _To, bool = (is_void<_From>::value || is_void<_To>::value || is_function<_To>::value || is_array<_To>::value // This special case is here only to avoid warnings. || (is_floating_point<typename remove_reference<_From>::type>::value && __is_int_or_cref<_To>::__value))> struct __is_convertible_helper { // "An imaginary lvalue of type From...". static const bool __value = (__is_convertible_simple<typename add_reference<_From>::type, _To>::__value); }; template<typename _From, typename _To> struct __is_convertible_helper<_From, _To, true> { static const bool __value = (is_void<_To>::value || (__is_int_or_cref<_To>::__value && !is_void<_From>::value)); }; template<typename _From, typename _To> struct is_convertible : public integral_constant<bool, __is_convertible_helper<_From, _To>::__value> { }; // reference modifications [4.7.2]. template<typename _Tp> struct remove_reference { typedef _Tp type; }; template<typename _Tp> struct remove_reference<_Tp&> { typedef _Tp type; }; // NB: Careful with reference to void. template<typename _Tp, bool = (is_void<_Tp>::value || is_reference<_Tp>::value)> struct __add_reference_helper { typedef _Tp& type; }; template<typename _Tp> struct __add_reference_helper<_Tp, true> { typedef _Tp type; }; template<typename _Tp> struct add_reference : public __add_reference_helper<_Tp> { }; // other transformations [4.8]. template<std::size_t _Len, std::size_t _Align> struct aligned_storage { union type { unsigned char __data[_Len]; struct __attribute__((__aligned__((_Align)))) { } __align; }; }; #undef _DEFINE_SPEC_0_HELPER #undef _DEFINE_SPEC_1_HELPER #undef _DEFINE_SPEC_2_HELPER #undef _DEFINE_SPEC /// @} group metaprogramming } _GLIBCXX_END_NAMESPACE_VERSION } #endif // _GLIBCXX_TR1_TYPE_TRAITS