645 lines
18 KiB
C++
645 lines
18 KiB
C++
// TR1 type_traits -*- C++ -*-
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// Copyright (C) 2004, 2005 Free Software Foundation, Inc.
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//
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// This file is part of the GNU ISO C++ Library. This library is free
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// software; you can redistribute it and/or modify it under the
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// terms of the GNU General Public License as published by the
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// Free Software Foundation; either version 2, or (at your option)
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// any later version.
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// This library is distributed in the hope that it will be useful,
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// but WITHOUT ANY WARRANTY; without even the implied warranty of
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// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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// GNU General Public License for more details.
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// You should have received a copy of the GNU General Public License along
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// with this library; see the file COPYING. If not, write to the Free
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// Software Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307,
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// USA.
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// As a special exception, you may use this file as part of a free software
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// library without restriction. Specifically, if other files instantiate
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// templates or use macros or inline functions from this file, or you compile
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// this file and link it with other files to produce an executable, this
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// file does not by itself cause the resulting executable to be covered by
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// the GNU General Public License. This exception does not however
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// invalidate any other reasons why the executable file might be covered by
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// the GNU General Public License.
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/** @file
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* This is a TR1 C++ Library header.
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*/
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#ifndef _TYPE_TRAITS
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#define _TYPE_TRAITS 1
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#include <bits/c++config.h>
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#include <tr1/type_traits_fwd.h>
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// namespace std::tr1
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namespace std
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{
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namespace tr1
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{
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// For use in is_enum, is_abstract and elsewhere.
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struct __sfinae_types
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{
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typedef char __one;
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typedef struct { char __arr[2]; } __two;
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};
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template<typename _From, typename _To>
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struct __conv_helper
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: public __sfinae_types
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{
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private:
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static __one __test(_To);
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static __two __test(...);
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static _From __makeFrom();
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public:
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static const bool __value = sizeof(__test(__makeFrom())) == 1;
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};
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#define _DEFINE_SPEC_BODY(_Value) \
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: public integral_constant<bool, _Value> { };
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#define _DEFINE_SPEC_0_HELPER(_Spec, _Value) \
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template<> \
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struct _Spec \
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_DEFINE_SPEC_BODY(_Value)
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#define _DEFINE_SPEC_1_HELPER(_Spec, _Value) \
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template<typename _Tp> \
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struct _Spec \
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_DEFINE_SPEC_BODY(_Value)
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#define _DEFINE_SPEC_2_HELPER(_Spec, _Value) \
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template<typename _Tp, typename _Cp> \
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struct _Spec \
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_DEFINE_SPEC_BODY(_Value)
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#define _DEFINE_SPEC(_Order, _Trait, _Type, _Value) \
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_DEFINE_SPEC_##_Order##_HELPER(_Trait<_Type>, _Value) \
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_DEFINE_SPEC_##_Order##_HELPER(_Trait<_Type const>, _Value) \
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_DEFINE_SPEC_##_Order##_HELPER(_Trait<_Type volatile>, _Value) \
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_DEFINE_SPEC_##_Order##_HELPER(_Trait<_Type const volatile>, _Value)
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/// @brief helper classes [4.3].
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template<typename _Tp, _Tp __v>
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struct integral_constant
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{
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static const _Tp value = __v;
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typedef _Tp value_type;
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typedef integral_constant<_Tp, __v> type;
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};
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typedef integral_constant<bool, true> true_type;
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typedef integral_constant<bool, false> false_type;
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/// @brief primary type categories [4.5.1].
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template<typename>
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struct is_void
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: public false_type { };
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_DEFINE_SPEC(0, is_void, void, true)
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template<typename>
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struct is_integral
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: public false_type { };
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_DEFINE_SPEC(0, is_integral, bool, true)
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_DEFINE_SPEC(0, is_integral, char, true)
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_DEFINE_SPEC(0, is_integral, signed char, true)
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_DEFINE_SPEC(0, is_integral, unsigned char, true)
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#ifdef _GLIBCXX_USE_WCHAR_T
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_DEFINE_SPEC(0, is_integral, wchar_t, true)
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#endif
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_DEFINE_SPEC(0, is_integral, short, true)
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_DEFINE_SPEC(0, is_integral, unsigned short, true)
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_DEFINE_SPEC(0, is_integral, int, true)
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_DEFINE_SPEC(0, is_integral, unsigned int, true)
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_DEFINE_SPEC(0, is_integral, long, true)
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_DEFINE_SPEC(0, is_integral, unsigned long, true)
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_DEFINE_SPEC(0, is_integral, long long, true)
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_DEFINE_SPEC(0, is_integral, unsigned long long, true)
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template<typename>
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struct is_floating_point
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: public false_type { };
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_DEFINE_SPEC(0, is_floating_point, float, true)
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_DEFINE_SPEC(0, is_floating_point, double, true)
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_DEFINE_SPEC(0, is_floating_point, long double, true)
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template<typename>
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struct is_array
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: public false_type { };
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template<typename _Tp, std::size_t _Size>
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struct is_array<_Tp[_Size]>
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: public true_type { };
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template<typename _Tp>
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struct is_array<_Tp[]>
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: public true_type { };
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template<typename>
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struct is_pointer
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: public false_type { };
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_DEFINE_SPEC(1, is_pointer, _Tp*, true)
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template<typename>
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struct is_reference
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: public false_type { };
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template<typename _Tp>
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struct is_reference<_Tp&>
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: public true_type { };
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template<typename>
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struct is_member_object_pointer
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: public false_type { };
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_DEFINE_SPEC(2, is_member_object_pointer, _Tp _Cp::*,
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!is_function<_Tp>::value)
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template<typename>
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struct is_member_function_pointer
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: public false_type { };
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_DEFINE_SPEC(2, is_member_function_pointer, _Tp _Cp::*,
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is_function<_Tp>::value)
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template<typename _Tp>
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struct is_enum
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: public integral_constant<bool, !(is_fundamental<_Tp>::value
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|| is_array<_Tp>::value
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|| is_pointer<_Tp>::value
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|| is_reference<_Tp>::value
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|| is_member_pointer<_Tp>::value
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|| is_function<_Tp>::value
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|| __is_union_or_class<_Tp>::value)>
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{ };
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template<typename>
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struct is_union { };
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template<typename>
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struct is_class { };
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template<typename _Tp, bool = (is_void<_Tp>::value
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|| is_reference<_Tp>::value)>
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struct __is_function_helper
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{
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static const bool __value = (__conv_helper<typename
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add_reference<_Tp>::type, typename
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add_pointer<_Tp>::type>::__value);
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};
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template<typename _Tp>
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struct __is_function_helper<_Tp, true>
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{ static const bool __value = false; };
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template<typename _Tp>
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struct is_function
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: public integral_constant<bool, __is_function_helper<_Tp>::__value>
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{ };
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/// @brief composite type traits [4.5.2].
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template<typename _Tp>
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struct is_arithmetic
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: public integral_constant<bool, (is_integral<_Tp>::value
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|| is_floating_point<_Tp>::value)>
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{ };
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template<typename _Tp>
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struct is_fundamental
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: public integral_constant<bool, (is_arithmetic<_Tp>::value
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|| is_void<_Tp>::value)>
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{ };
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template<typename _Tp>
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struct is_object
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: public integral_constant<bool, !(is_function<_Tp>::value
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|| is_reference<_Tp>::value
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|| is_void<_Tp>::value)>
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{ };
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template<typename _Tp>
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struct is_scalar
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: public integral_constant<bool, (is_arithmetic<_Tp>::value
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|| is_enum<_Tp>::value
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|| is_pointer<_Tp>::value
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|| is_member_pointer<_Tp>::value)>
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{ };
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template<typename _Tp>
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struct is_compound
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: public integral_constant<bool, !is_fundamental<_Tp>::value> { };
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template<typename _Tp>
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struct is_member_pointer
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: public integral_constant<bool,
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(is_member_object_pointer<_Tp>::value
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|| is_member_function_pointer<_Tp>::value)>
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{ };
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template<typename _Tp>
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struct __is_union_or_class_helper
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: public __sfinae_types
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{
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private:
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template<typename _Up>
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static __one __test(int _Up::*);
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template<typename>
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static __two __test(...);
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public:
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static const bool __value = sizeof(__test<_Tp>(0)) == 1;
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};
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// Extension.
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template<typename _Tp>
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struct __is_union_or_class
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: public integral_constant<bool, __is_union_or_class_helper<_Tp>::__value>
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{ };
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/// @brief type properties [4.5.3].
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template<typename>
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struct is_const
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: public false_type { };
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template<typename _Tp>
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struct is_const<_Tp const>
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: public true_type { };
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template<typename>
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struct is_volatile
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: public false_type { };
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template<typename _Tp>
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struct is_volatile<_Tp volatile>
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: public true_type { };
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template<typename _Tp>
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struct is_pod
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: public integral_constant<bool, (is_void<_Tp>::value
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|| is_scalar<typename
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remove_all_extents<_Tp>::type>::value)>
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{ };
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// N.B. Without compiler support we cannot tell union from class types,
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// and is_empty doesn't work at all with the former.
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template<typename _Tp, bool = !__is_union_or_class<_Tp>::value>
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struct __is_empty_helper
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{
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private:
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template<typename>
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struct __ebo_1 { };
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template<typename _Up>
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struct __ebo_2
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: public _Up { };
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public:
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static const bool __value = sizeof(__ebo_1<_Tp>) == sizeof(__ebo_2<_Tp>);
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};
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template<typename _Tp>
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struct __is_empty_helper<_Tp, true>
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{ static const bool __value = false; };
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template<typename _Tp>
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struct is_empty
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: public integral_constant<bool, __is_empty_helper<_Tp>::__value>
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{ };
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// Exploit the resolution DR core/337.
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template<typename _Tp, bool = !is_object<_Tp>::value>
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struct __is_abstract_helper
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: public __sfinae_types
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{
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private:
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template<typename>
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static __one __test(...);
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template<typename _Up>
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static __two __test(_Up(*)[1]);
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public:
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static const bool __value = sizeof(__test<_Tp>(0)) == 1;
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};
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template<typename _Tp>
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struct __is_abstract_helper<_Tp, true>
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{ static const bool __value = false; };
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template<typename _Tp>
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struct is_abstract
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: public integral_constant<bool, __is_abstract_helper<_Tp>::__value> { };
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template<typename _Tp>
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struct has_trivial_constructor
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: public integral_constant<bool, is_pod<_Tp>::value> { };
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template<typename _Tp>
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struct has_trivial_copy
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: public integral_constant<bool, (is_pod<_Tp>::value
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&& !is_volatile<_Tp>::value)> { };
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template<typename _Tp>
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struct has_trivial_assign
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: public integral_constant<bool, (is_pod<_Tp>::value
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&& !is_const<_Tp>::value
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&& !is_volatile<_Tp>::value)> { };
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template<typename _Tp>
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struct has_trivial_destructor
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: public integral_constant<bool, is_pod<_Tp>::value> { };
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template<typename _Tp>
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struct has_nothrow_constructor
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: public integral_constant<bool, is_pod<_Tp>::value> { };
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template<typename _Tp>
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struct has_nothrow_copy
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: public integral_constant<bool, (is_pod<_Tp>::value
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&& !is_volatile<_Tp>::value)> { };
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template<typename _Tp>
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struct has_nothrow_assign
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: public integral_constant<bool, (is_pod<_Tp>::value
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&& !is_const<_Tp>::value
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&& !is_volatile<_Tp>::value)> { };
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template<typename>
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struct has_virtual_destructor
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: public false_type { };
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template<typename>
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struct is_signed
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: public false_type { };
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_DEFINE_SPEC(0, is_signed, signed char, true)
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_DEFINE_SPEC(0, is_signed, short, true)
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_DEFINE_SPEC(0, is_signed, int, true)
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_DEFINE_SPEC(0, is_signed, long, true)
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_DEFINE_SPEC(0, is_signed, long long, true)
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template<typename>
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struct is_unsigned
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: public false_type { };
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_DEFINE_SPEC(0, is_unsigned, unsigned char, true)
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_DEFINE_SPEC(0, is_unsigned, unsigned short, true)
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_DEFINE_SPEC(0, is_unsigned, unsigned int, true)
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_DEFINE_SPEC(0, is_unsigned, unsigned long, true)
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_DEFINE_SPEC(0, is_unsigned, unsigned long long, true)
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template<typename _Tp>
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struct alignment_of
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: public integral_constant<std::size_t, __alignof__(_Tp)> { };
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template<typename>
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struct rank
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: public integral_constant<std::size_t, 0> { };
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template<typename _Tp, std::size_t _Size>
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struct rank<_Tp[_Size]>
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: public integral_constant<std::size_t, 1 + rank<_Tp>::value> { };
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template<typename _Tp>
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struct rank<_Tp[]>
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: public integral_constant<std::size_t, 1 + rank<_Tp>::value> { };
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template<typename, unsigned>
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struct extent
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: public integral_constant<std::size_t, 0> { };
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template<typename _Tp, unsigned _Uint, std::size_t _Size>
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struct extent<_Tp[_Size], _Uint>
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: public integral_constant<std::size_t,
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_Uint == 0 ? _Size : extent<_Tp,
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_Uint - 1>::value>
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{ };
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template<typename _Tp, unsigned _Uint>
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struct extent<_Tp[], _Uint>
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: public integral_constant<std::size_t,
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_Uint == 0 ? 0 : extent<_Tp,
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_Uint - 1>::value>
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{ };
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/// @brief relationships between types [4.6].
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template<typename, typename>
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struct is_same
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: public false_type { };
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template<typename _Tp>
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struct is_same<_Tp, _Tp>
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: public true_type { };
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template<typename _Tp>
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struct __is_int_or_cref
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{
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typedef typename remove_reference<_Tp>::type __rr_Tp;
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static const bool __value = (is_integral<_Tp>::value
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|| (is_integral<__rr_Tp>::value
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&& is_const<__rr_Tp>::value
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&& !is_volatile<__rr_Tp>::value));
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};
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template<typename _From, typename _To,
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bool = (is_function<_To>::value || is_array<_To>::value
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// This special case is here only to avoid warnings.
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|| (is_floating_point<typename
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remove_reference<_From>::type>::value
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&& __is_int_or_cref<_To>::__value))>
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struct __is_convertible_helper
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{
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// "An imaginary lvalue of type From...".
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static const bool __value = (__conv_helper<typename
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add_reference<_From>::type, _To>::__value);
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};
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template<typename _From, typename _To>
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struct __is_convertible_helper<_From, _To, true>
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{ static const bool __value = __is_int_or_cref<_To>::__value; };
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template<typename _From, typename _To>
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struct is_convertible
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: public integral_constant<bool,
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__is_convertible_helper<_From, _To>::__value>
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{ };
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/// @brief const-volatile modifications [4.7.1].
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template<typename _Tp>
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struct remove_const
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{ typedef _Tp type; };
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template<typename _Tp>
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struct remove_const<_Tp const>
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{ typedef _Tp type; };
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template<typename _Tp>
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struct remove_volatile
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{ typedef _Tp type; };
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template<typename _Tp>
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struct remove_volatile<_Tp volatile>
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{ typedef _Tp type; };
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template<typename _Tp>
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struct remove_cv
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{
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typedef typename
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remove_const<typename remove_volatile<_Tp>::type>::type type;
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};
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template<typename _Tp>
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struct add_const
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{ typedef _Tp const type; };
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template<typename _Tp>
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struct add_volatile
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{ typedef _Tp volatile type; };
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template<typename _Tp>
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struct add_cv
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{
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typedef typename
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add_const<typename add_volatile<_Tp>::type>::type type;
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};
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/// @brief reference modifications [4.7.2].
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template<typename _Tp>
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struct remove_reference
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{ typedef _Tp type; };
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template<typename _Tp>
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struct remove_reference<_Tp&>
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{ typedef _Tp type; };
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template<typename _Tp>
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struct add_reference
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{ typedef _Tp& type; };
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template<typename _Tp>
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struct add_reference<_Tp&>
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{ typedef _Tp& type; };
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/// @brief array modififications [4.7.3].
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template<typename _Tp>
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struct remove_extent
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{ typedef _Tp type; };
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template<typename _Tp, std::size_t _Size>
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struct remove_extent<_Tp[_Size]>
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{ typedef _Tp type; };
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template<typename _Tp>
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struct remove_extent<_Tp[]>
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{ typedef _Tp type; };
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template<typename _Tp>
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struct remove_all_extents
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{ typedef _Tp type; };
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template<typename _Tp, std::size_t _Size>
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struct remove_all_extents<_Tp[_Size]>
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{ typedef typename remove_all_extents<_Tp>::type type; };
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template<typename _Tp>
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|
struct remove_all_extents<_Tp[]>
|
|
{ typedef typename remove_all_extents<_Tp>::type type; };
|
|
|
|
/// @brief pointer modifications [4.7.4].
|
|
#undef _DEFINE_SPEC_BODY
|
|
#define _DEFINE_SPEC_BODY(_Value) \
|
|
{ typedef _Tp type; };
|
|
|
|
template<typename _Tp>
|
|
struct remove_pointer
|
|
{ typedef _Tp type; };
|
|
_DEFINE_SPEC(1, remove_pointer, _Tp*, false)
|
|
|
|
template<typename _Tp>
|
|
struct add_pointer
|
|
{ typedef typename remove_reference<_Tp>::type* type; };
|
|
|
|
/// @brief other transformations [4.8].
|
|
|
|
// Due to c++/19163 and c++/17743, for the time being we cannot use
|
|
// the correct, neat implementation :-(
|
|
//
|
|
// template<std::size_t _Len, std::size_t _Align>
|
|
// struct aligned_storage
|
|
// { typedef char type[_Len] __attribute__((__aligned__(_Align))); }
|
|
//
|
|
// Temporary workaround, useful for Align up to 32:
|
|
template<std::size_t, std::size_t>
|
|
struct aligned_storage { };
|
|
|
|
template<std::size_t _Len>
|
|
struct aligned_storage<_Len, 1>
|
|
{
|
|
union type
|
|
{
|
|
unsigned char __data[_Len];
|
|
char __align __attribute__((__aligned__(1)));
|
|
};
|
|
};
|
|
|
|
template<std::size_t _Len>
|
|
struct aligned_storage<_Len, 2>
|
|
{
|
|
union type
|
|
{
|
|
unsigned char __data[_Len];
|
|
char __align __attribute__((__aligned__(2)));
|
|
};
|
|
};
|
|
|
|
template<std::size_t _Len>
|
|
struct aligned_storage<_Len, 4>
|
|
{
|
|
union type
|
|
{
|
|
unsigned char __data[_Len];
|
|
char __align __attribute__((__aligned__(4)));
|
|
};
|
|
};
|
|
|
|
template<std::size_t _Len>
|
|
struct aligned_storage<_Len, 8>
|
|
{
|
|
union type
|
|
{
|
|
unsigned char __data[_Len];
|
|
char __align __attribute__((__aligned__(8)));
|
|
};
|
|
};
|
|
|
|
template<std::size_t _Len>
|
|
struct aligned_storage<_Len, 16>
|
|
{
|
|
union type
|
|
{
|
|
unsigned char __data[_Len];
|
|
char __align __attribute__((__aligned__(16)));
|
|
};
|
|
};
|
|
|
|
template<std::size_t _Len>
|
|
struct aligned_storage<_Len, 32>
|
|
{
|
|
union type
|
|
{
|
|
unsigned char __data[_Len];
|
|
char __align __attribute__((__aligned__(32)));
|
|
};
|
|
};
|
|
|
|
#undef _DEFINE_SPEC_0_HELPER
|
|
#undef _DEFINE_SPEC_1_HELPER
|
|
#undef _DEFINE_SPEC_2_HELPER
|
|
#undef _DEFINE_SPEC
|
|
#undef _DEFINE_SPEC_BODY
|
|
|
|
}
|
|
}
|
|
|
|
#endif
|