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// TR1 type_traits -*- C++ -*-
// Copyright (C) 2007, 2008, 2009 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_impl/type_traits
* This is an internal header file, included by other library headers.
* You should not attempt to use it directly.
*/
namespace std
{
_GLIBCXX_BEGIN_NAMESPACE_TR1
/**
* @defgroup metaprogramming Type Traits
* @ingroup utilities
*
* Compile time type transformation and information.
* @{
*/
// For use in __is_convertible_simple.
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
#ifdef _GLIBCXX_INCLUDE_AS_CXX0X
_DEFINE_SPEC(0, __is_integral_helper, char16_t, true)
_DEFINE_SPEC(0, __is_integral_helper, char32_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; };
#undef _DEFINE_SPEC_0_HELPER
#undef _DEFINE_SPEC_1_HELPER
#undef _DEFINE_SPEC_2_HELPER
#undef _DEFINE_SPEC
// @} group metaprogramming
_GLIBCXX_END_NAMESPACE_TR1
}