type_traits
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// C++11 <type_traits> -*- C++ -*-
// Copyright (C) 2007-2014 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 include/type_traits
* This is a Standard C++ Library header.
*/
#ifndef _GLIBCXX_TYPE_TRAITS
#define _GLIBCXX_TYPE_TRAITS 1
#pragma GCC system_header
#if __cplusplus < 201103L
# include <bits/c++0x_warning.h>
#else
#include <bits/c++config.h>
namespace std _GLIBCXX_VISIBILITY(default)
{
_GLIBCXX_BEGIN_NAMESPACE_VERSION
/**
* @defgroup metaprogramming Metaprogramming
* @ingroup utilities
*
* Template utilities for compile-time introspection and modification,
* including type classification traits, type property inspection traits
* and type transformation traits.
*
* @{
*/
/// integral_constant
template<typename _Tp, _Tp __v>
struct integral_constant
{
static constexpr _Tp value = __v;
typedef _Tp value_type;
typedef integral_constant<_Tp, __v> type;
constexpr operator value_type() const { return value; }
#if __cplusplus > 201103L
constexpr value_type operator()() const { return value; }
#endif
};
template<typename _Tp, _Tp __v>
constexpr _Tp integral_constant<_Tp, __v>::value;
/// The type used as a compile-time boolean with true value.
typedef integral_constant<bool, true> true_type;
/// The type used as a compile-time boolean with false value.
typedef integral_constant<bool, false> false_type;
// Meta programming helper types.
template<bool, typename, typename>
struct conditional;
template<typename...>
struct __or_;
template<>
struct __or_<>
: public false_type
{ };
template<typename _B1>
struct __or_<_B1>
: public _B1
{ };
template<typename _B1, typename _B2>
struct __or_<_B1, _B2>
: public conditional<_B1::value, _B1, _B2>::type
{ };
template<typename _B1, typename _B2, typename _B3, typename... _Bn>
struct __or_<_B1, _B2, _B3, _Bn...>
: public conditional<_B1::value, _B1, __or_<_B2, _B3, _Bn...>>::type
{ };
template<typename...>
struct __and_;
template<>
struct __and_<>
: public true_type
{ };
template<typename _B1>
struct __and_<_B1>
: public _B1
{ };
template<typename _B1, typename _B2>
struct __and_<_B1, _B2>
: public conditional<_B1::value, _B2, _B1>::type
{ };
template<typename _B1, typename _B2, typename _B3, typename... _Bn>
struct __and_<_B1, _B2, _B3, _Bn...>
: public conditional<_B1::value, __and_<_B2, _B3, _Bn...>, _B1>::type
{ };
template<typename _Pp>
struct __not_
: public integral_constant<bool, !_Pp::value>
{ };
// For several sfinae-friendly trait implementations we transport both the
// result information (as the member type) and the failure information (no
// member type). This is very similar to std::enable_if, but we cannot use
// them, because we need to derive from them as an implementation detail.
template<typename _Tp>
struct __success_type
{ typedef _Tp type; };
struct __failure_type
{ };
// Primary type categories.
template<typename>
struct remove_cv;
template<typename>
struct __is_void_helper
: public false_type { };
template<>
struct __is_void_helper<void>
: public true_type { };
/// is_void
template<typename _Tp>
struct is_void
: public __is_void_helper<typename remove_cv<_Tp>::type>::type
{ };
template<typename>
struct __is_integral_helper
: public false_type { };
template<>
struct __is_integral_helper<bool>
: public true_type { };
template<>
struct __is_integral_helper<char>
: public true_type { };
template<>
struct __is_integral_helper<signed char>
: public true_type { };
template<>
struct __is_integral_helper<unsigned char>
: public true_type { };
#ifdef _GLIBCXX_USE_WCHAR_T
template<>
struct __is_integral_helper<wchar_t>
: public true_type { };
#endif
template<>
struct __is_integral_helper<char16_t>
: public true_type { };
template<>
struct __is_integral_helper<char32_t>
: public true_type { };
template<>
struct __is_integral_helper<short>
: public true_type { };
template<>
struct __is_integral_helper<unsigned short>
: public true_type { };
template<>
struct __is_integral_helper<int>
: public true_type { };
template<>
struct __is_integral_helper<unsigned int>
: public true_type { };
template<>
struct __is_integral_helper<long>
: public true_type { };
template<>
struct __is_integral_helper<unsigned long>
: public true_type { };
template<>
struct __is_integral_helper<long long>
: public true_type { };
template<>
struct __is_integral_helper<unsigned long long>
: public true_type { };
#if !defined(__STRICT_ANSI__) && defined(_GLIBCXX_USE_INT128)
template<>
struct __is_integral_helper<__int128>
: public true_type { };
template<>
struct __is_integral_helper<unsigned __int128>
: public true_type { };
#endif
/// is_integral
template<typename _Tp>
struct is_integral
: public __is_integral_helper<typename remove_cv<_Tp>::type>::type
{ };
template<typename>
struct __is_floating_point_helper
: public false_type { };
template<>
struct __is_floating_point_helper<float>
: public true_type { };
template<>
struct __is_floating_point_helper<double>
: public true_type { };
template<>
struct __is_floating_point_helper<long double>
: public true_type { };
#if !defined(__STRICT_ANSI__) && defined(_GLIBCXX_USE_FLOAT128)
template<>
struct __is_floating_point_helper<__float128>
: public true_type { };
#endif
/// is_floating_point
template<typename _Tp>
struct is_floating_point
: public __is_floating_point_helper<typename remove_cv<_Tp>::type>::type
{ };
/// 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 { };
template<typename _Tp>
struct __is_pointer_helper<_Tp*>
: public true_type { };
/// is_pointer
template<typename _Tp>
struct is_pointer
: public __is_pointer_helper<typename remove_cv<_Tp>::type>::type
{ };
/// is_lvalue_reference
template<typename>
struct is_lvalue_reference
: public false_type { };
template<typename _Tp>
struct is_lvalue_reference<_Tp&>
: public true_type { };
/// is_rvalue_reference
template<typename>
struct is_rvalue_reference
: public false_type { };
template<typename _Tp>
struct is_rvalue_reference<_Tp&&>
: public true_type { };
template<typename>
struct is_function;
template<typename>
struct __is_member_object_pointer_helper
: public false_type { };
template<typename _Tp, typename _Cp>
struct __is_member_object_pointer_helper<_Tp _Cp::*>
: public integral_constant<bool, !is_function<_Tp>::value> { };
/// is_member_object_pointer
template<typename _Tp>
struct is_member_object_pointer
: public __is_member_object_pointer_helper<
typename remove_cv<_Tp>::type>::type
{ };
template<typename>
struct __is_member_function_pointer_helper
: public false_type { };
template<typename _Tp, typename _Cp>
struct __is_member_function_pointer_helper<_Tp _Cp::*>
: public integral_constant<bool, is_function<_Tp>::value> { };
/// is_member_function_pointer
template<typename _Tp>
struct is_member_function_pointer
: public __is_member_function_pointer_helper<
typename remove_cv<_Tp>::type>::type
{ };
/// 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...) &&>
: 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......) &>
: 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...) 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......) 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...) 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......) 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 { };
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 { };
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 { };
template<typename>
struct __is_null_pointer_helper
: public false_type { };
template<>
struct __is_null_pointer_helper<std::nullptr_t>
: public true_type { };
/// is_null_pointer (LWG 2247).
template<typename _Tp>
struct is_null_pointer
: public __is_null_pointer_helper<typename remove_cv<_Tp>::type>::type
{ };
/// __is_nullptr_t (extension).
template<typename _Tp>
struct __is_nullptr_t
: public is_null_pointer<_Tp>
{ };
// Composite type categories.
/// is_reference
template<typename _Tp>
struct is_reference
: public __or_<is_lvalue_reference<_Tp>,
is_rvalue_reference<_Tp>>::type
{ };
/// is_arithmetic
template<typename _Tp>
struct is_arithmetic
: public __or_<is_integral<_Tp>, is_floating_point<_Tp>>::type
{ };
/// is_fundamental
template<typename _Tp>
struct is_fundamental
: public __or_<is_arithmetic<_Tp>, is_void<_Tp>,
is_null_pointer<_Tp>>::type
{ };
/// is_object
template<typename _Tp>
struct is_object
: public __not_<__or_<is_function<_Tp>, is_reference<_Tp>,
is_void<_Tp>>>::type
{ };
template<typename>
struct is_member_pointer;
/// is_scalar
template<typename _Tp>
struct is_scalar
: public __or_<is_arithmetic<_Tp>, is_enum<_Tp>, is_pointer<_Tp>,
is_member_pointer<_Tp>, is_null_pointer<_Tp>>::type
{ };
/// is_compound
template<typename _Tp>
struct is_compound
: public integral_constant<bool, !is_fundamental<_Tp>::value> { };
template<typename _Tp>
struct __is_member_pointer_helper
: public false_type { };
template<typename _Tp, typename _Cp>
struct __is_member_pointer_helper<_Tp _Cp::*>
: public true_type { };
/// is_member_pointer
template<typename _Tp>
struct is_member_pointer
: public __is_member_pointer_helper<typename remove_cv<_Tp>::type>::type
{ };
// Utility to detect referenceable types ([defns.referenceable]).
template<typename _Tp>
struct __is_referenceable
: public __or_<is_object<_Tp>, is_reference<_Tp>>::type
{ };
template<typename _Res, typename... _Args>
struct __is_referenceable<_Res(_Args...)>
: public true_type
{ };
template<typename _Res, typename... _Args>
struct __is_referenceable<_Res(_Args......)>
: public true_type
{ };
// Type properties.
/// 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_trivial
template<typename _Tp>
struct is_trivial
: public integral_constant<bool, __is_trivial(_Tp)>
{ };
// is_trivially_copyable (still unimplemented)
/// is_standard_layout
template<typename _Tp>
struct is_standard_layout
: public integral_constant<bool, __is_standard_layout(_Tp)>
{ };
/// is_pod
// Could use is_standard_layout && is_trivial instead of the builtin.
template<typename _Tp>
struct is_pod
: public integral_constant<bool, __is_pod(_Tp)>
{ };
/// is_literal_type
template<typename _Tp>
struct is_literal_type
: public integral_constant<bool, __is_literal_type(_Tp)>
{ };
/// 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)>
{ };
template<typename _Tp,
bool = is_arithmetic<_Tp>::value>
struct __is_signed_helper
: public false_type { };
template<typename _Tp>
struct __is_signed_helper<_Tp, true>
: public integral_constant<bool, _Tp(-1) < _Tp(0)>
{ };
/// is_signed
template<typename _Tp>
struct is_signed
: public __is_signed_helper<_Tp>::type
{ };
/// is_unsigned
template<typename _Tp>
struct is_unsigned
: public __and_<is_arithmetic<_Tp>, __not_<is_signed<_Tp>>>::type
{ };
// Destructible and constructible type properties.
template<typename>
struct add_rvalue_reference;
/**
* @brief Utility to simplify expressions used in unevaluated operands
* @ingroup utilities
*/
template<typename _Tp>
typename add_rvalue_reference<_Tp>::type declval() noexcept;
template<typename, unsigned = 0>
struct extent;
template<typename>
struct remove_all_extents;
template<typename _Tp>
struct __is_array_known_bounds
: public integral_constant<bool, (extent<_Tp>::value > 0)>
{ };
template<typename _Tp>
struct __is_array_unknown_bounds
: public __and_<is_array<_Tp>, __not_<extent<_Tp>>>::type
{ };
// In N3290 is_destructible does not say anything about function
// types and abstract types, see LWG 2049. This implementation
// describes function types as non-destructible and all complete
// object types as destructible, iff the explicit destructor
// call expression is wellformed.
struct __do_is_destructible_impl
{
template<typename _Tp, typename = decltype(declval<_Tp&>().~_Tp())>
static true_type __test(int);
template<typename>
static false_type __test(...);
};
template<typename _Tp>
struct __is_destructible_impl
: public __do_is_destructible_impl
{
typedef decltype(__test<_Tp>(0)) type;
};
template<typename _Tp,
bool = __or_<is_void<_Tp>,
__is_array_unknown_bounds<_Tp>,
is_function<_Tp>>::value,
bool = __or_<is_reference<_Tp>, is_scalar<_Tp>>::value>
struct __is_destructible_safe;
template<typename _Tp>
struct __is_destructible_safe<_Tp, false, false>
: public __is_destructible_impl<typename
remove_all_extents<_Tp>::type>::type
{ };
template<typename _Tp>
struct __is_destructible_safe<_Tp, true, false>
: public false_type { };
template<typename _Tp>
struct __is_destructible_safe<_Tp, false, true>
: public true_type { };
/// is_destructible
template<typename _Tp>
struct is_destructible
: public __is_destructible_safe<_Tp>::type
{ };
// is_nothrow_destructible requires that is_destructible is
// satisfied as well. We realize that by mimicing the
// implementation of is_destructible but refer to noexcept(expr)
// instead of decltype(expr).
struct __do_is_nt_destructible_impl
{
template<typename _Tp>
static integral_constant<bool, noexcept(declval<_Tp&>().~_Tp())>
__test(int);
template<typename>
static false_type __test(...);
};
template<typename _Tp>
struct __is_nt_destructible_impl
: public __do_is_nt_destructible_impl
{
typedef decltype(__test<_Tp>(0)) type;
};
template<typename _Tp,
bool = __or_<is_void<_Tp>,
__is_array_unknown_bounds<_Tp>,
is_function<_Tp>>::value,
bool = __or_<is_reference<_Tp>, is_scalar<_Tp>>::value>
struct __is_nt_destructible_safe;
template<typename _Tp>
struct __is_nt_destructible_safe<_Tp, false, false>
: public __is_nt_destructible_impl<typename
remove_all_extents<_Tp>::type>::type
{ };
template<typename _Tp>
struct __is_nt_destructible_safe<_Tp, true, false>
: public false_type { };
template<typename _Tp>
struct __is_nt_destructible_safe<_Tp, false, true>
: public true_type { };
/// is_nothrow_destructible
template<typename _Tp>
struct is_nothrow_destructible
: public __is_nt_destructible_safe<_Tp>::type
{ };
struct __do_is_default_constructible_impl
{
template<typename _Tp, typename = decltype(_Tp())>
static true_type __test(int);
template<typename>
static false_type __test(...);
};
template<typename _Tp>
struct __is_default_constructible_impl
: public __do_is_default_constructible_impl
{
typedef decltype(__test<_Tp>(0)) type;
};
template<typename _Tp>
struct __is_default_constructible_atom
: public __and_<__not_<is_void<_Tp>>,
__is_default_constructible_impl<_Tp>>::type
{ };
template<typename _Tp, bool = is_array<_Tp>::value>
struct __is_default_constructible_safe;
// The following technique is a workaround for a current core language
// restriction, which does not allow for array types to occur in
// functional casts of the form T(). Complete arrays can be default-
// constructed, if the element type is default-constructible, but
// arrays with unknown bounds are not.
template<typename _Tp>
struct __is_default_constructible_safe<_Tp, true>
: public __and_<__is_array_known_bounds<_Tp>,
__is_default_constructible_atom<typename
remove_all_extents<_Tp>::type>>::type
{ };
template<typename _Tp>
struct __is_default_constructible_safe<_Tp, false>
: public __is_default_constructible_atom<_Tp>::type
{ };
/// is_default_constructible
template<typename _Tp>
struct is_default_constructible
: public __is_default_constructible_safe<_Tp>::type
{ };
// Implementation of is_constructible.
// The hardest part of this trait is the binary direct-initialization
// case, because we hit into a functional cast of the form T(arg).
// This implementation uses different strategies depending on the
// target type to reduce the test overhead as much as possible:
//
// a) For a reference target type, we use a static_cast expression
// modulo its extra cases.
//
// b) For a non-reference target type we use a ::new expression.
struct __do_is_static_castable_impl
{
template<typename _From, typename _To, typename
= decltype(static_cast<_To>(declval<_From>()))>
static true_type __test(int);
template<typename, typename>
static false_type __test(...);
};
template<typename _From, typename _To>
struct __is_static_castable_impl
: public __do_is_static_castable_impl
{
typedef decltype(__test<_From, _To>(0)) type;
};
template<typename _From, typename _To>
struct __is_static_castable_safe
: public __is_static_castable_impl<_From, _To>::type
{ };
// __is_static_castable
template<typename _From, typename _To>
struct __is_static_castable
: public integral_constant<bool, (__is_static_castable_safe<
_From, _To>::value)>
{ };
// Implementation for non-reference types. To meet the proper
// variable definition semantics, we also need to test for
// is_destructible in this case.
// This form should be simplified by a single expression:
// ::delete ::new _Tp(declval<_Arg>()), see c++/51222.
struct __do_is_direct_constructible_impl
{
template<typename _Tp, typename _Arg, typename
= decltype(::new _Tp(declval<_Arg>()))>
static true_type __test(int);
template<typename, typename>
static false_type __test(...);
};
template<typename _Tp, typename _Arg>
struct __is_direct_constructible_impl
: public __do_is_direct_constructible_impl
{
typedef decltype(__test<_Tp, _Arg>(0)) type;
};
template<typename _Tp, typename _Arg>
struct __is_direct_constructible_new_safe
: public __and_<is_destructible<_Tp>,
__is_direct_constructible_impl<_Tp, _Arg>>::type
{ };
template<typename, typename>
struct is_same;
template<typename, typename>
struct is_base_of;
template<typename>
struct remove_reference;
template<typename _From, typename _To, bool
= __not_<__or_<is_void<_From>,
is_function<_From>>>::value>
struct __is_base_to_derived_ref;
// Detect whether we have a downcast situation during
// reference binding.
template<typename _From, typename _To>
struct __is_base_to_derived_ref<_From, _To, true>
{
typedef typename remove_cv<typename remove_reference<_From
>::type>::type __src_t;
typedef typename remove_cv<typename remove_reference<_To
>::type>::type __dst_t;
typedef __and_<__not_<is_same<__src_t, __dst_t>>,
is_base_of<__src_t, __dst_t>> type;
static constexpr bool value = type::value;
};
template<typename _From, typename _To>
struct __is_base_to_derived_ref<_From, _To, false>
: public false_type
{ };
template<typename _From, typename _To, bool
= __and_<is_lvalue_reference<_From>,
is_rvalue_reference<_To>>::value>
struct __is_lvalue_to_rvalue_ref;
// Detect whether we have an lvalue of non-function type
// bound to a reference-compatible rvalue-reference.
template<typename _From, typename _To>
struct __is_lvalue_to_rvalue_ref<_From, _To, true>
{
typedef typename remove_cv<typename remove_reference<
_From>::type>::type __src_t;
typedef typename remove_cv<typename remove_reference<
_To>::type>::type __dst_t;
typedef __and_<__not_<is_function<__src_t>>,
__or_<is_same<__src_t, __dst_t>,
is_base_of<__dst_t, __src_t>>> type;
static constexpr bool value = type::value;
};
template<typename _From, typename _To>
struct __is_lvalue_to_rvalue_ref<_From, _To, false>
: public false_type
{ };
// Here we handle direct-initialization to a reference type as
// equivalent to a static_cast modulo overshooting conversions.
// These are restricted to the following conversions:
// a) A base class value to a derived class reference
// b) An lvalue to an rvalue-reference of reference-compatible
// types that are not functions
template<typename _Tp, typename _Arg>
struct __is_direct_constructible_ref_cast
: public __and_<__is_static_castable<_Arg, _Tp>,
__not_<__or_<__is_base_to_derived_ref<_Arg, _Tp>,
__is_lvalue_to_rvalue_ref<_Arg, _Tp>
>>>::type
{ };
template<typename _Tp, typename _Arg>
struct __is_direct_constructible_new
: public conditional<is_reference<_Tp>::value,
__is_direct_constructible_ref_cast<_Tp, _Arg>,
__is_direct_constructible_new_safe<_Tp, _Arg>
>::type
{ };
template<typename _Tp, typename _Arg>
struct __is_direct_constructible
: public __is_direct_constructible_new<_Tp, _Arg>::type
{ };
// Since default-construction and binary direct-initialization have
// been handled separately, the implementation of the remaining
// n-ary construction cases is rather straightforward. We can use
// here a functional cast, because array types are excluded anyway
// and this form is never interpreted as a C cast.
struct __do_is_nary_constructible_impl
{
template<typename _Tp, typename... _Args, typename
= decltype(_Tp(declval<_Args>()...))>
static true_type __test(int);
template<typename, typename...>
static false_type __test(...);
};
template<typename _Tp, typename... _Args>
struct __is_nary_constructible_impl
: public __do_is_nary_constructible_impl
{
typedef decltype(__test<_Tp, _Args...>(0)) type;
};
template<typename _Tp, typename... _Args>
struct __is_nary_constructible
: public __is_nary_constructible_impl<_Tp, _Args...>::type
{
static_assert(sizeof...(_Args) > 1,
"Only useful for > 1 arguments");
};
template<typename _Tp, typename... _Args>
struct __is_constructible_impl
: public __is_nary_constructible<_Tp, _Args...>
{ };
template<typename _Tp, typename _Arg>
struct __is_constructible_impl<_Tp, _Arg>
: public __is_direct_constructible<_Tp, _Arg>
{ };
template<typename _Tp>
struct __is_constructible_impl<_Tp>
: public is_default_constructible<_Tp>
{ };
/// is_constructible
template<typename _Tp, typename... _Args>
struct is_constructible
: public __is_constructible_impl<_Tp, _Args...>::type
{ };
template<typename _Tp, bool = __is_referenceable<_Tp>::value>
struct __is_copy_constructible_impl;
template<typename _Tp>
struct __is_copy_constructible_impl<_Tp, false>
: public false_type { };
template<typename _Tp>
struct __is_copy_constructible_impl<_Tp, true>
: public is_constructible<_Tp, const _Tp&>
{ };
/// is_copy_constructible
template<typename _Tp>
struct is_copy_constructible
: public __is_copy_constructible_impl<_Tp>
{ };
template<typename _Tp, bool = __is_referenceable<_Tp>::value>
struct __is_move_constructible_impl;
template<typename _Tp>
struct __is_move_constructible_impl<_Tp, false>
: public false_type { };
template<typename _Tp>
struct __is_move_constructible_impl<_Tp, true>
: public is_constructible<_Tp, _Tp&&>
{ };
/// is_move_constructible
template<typename _Tp>
struct is_move_constructible
: public __is_move_constructible_impl<_Tp>
{ };
template<typename _Tp>
struct __is_nt_default_constructible_atom
: public integral_constant<bool, noexcept(_Tp())>
{ };
template<typename _Tp, bool = is_array<_Tp>::value>
struct __is_nt_default_constructible_impl;
template<typename _Tp>
struct __is_nt_default_constructible_impl<_Tp, true>
: public __and_<__is_array_known_bounds<_Tp>,
__is_nt_default_constructible_atom<typename
remove_all_extents<_Tp>::type>>::type
{ };
template<typename _Tp>
struct __is_nt_default_constructible_impl<_Tp, false>
: public __is_nt_default_constructible_atom<_Tp>
{ };
/// is_nothrow_default_constructible
template<typename _Tp>
struct is_nothrow_default_constructible
: public __and_<is_default_constructible<_Tp>,
__is_nt_default_constructible_impl<_Tp>>::type
{ };
template<typename _Tp, typename... _Args>
struct __is_nt_constructible_impl
: public integral_constant<bool, noexcept(_Tp(declval<_Args>()...))>
{ };
template<typename _Tp, typename _Arg>
struct __is_nt_constructible_impl<_Tp, _Arg>
: public integral_constant<bool,
noexcept(static_cast<_Tp>(declval<_Arg>()))>
{ };
template<typename _Tp>
struct __is_nt_constructible_impl<_Tp>
: public is_nothrow_default_constructible<_Tp>
{ };
/// is_nothrow_constructible
template<typename _Tp, typename... _Args>
struct is_nothrow_constructible
: public __and_<is_constructible<_Tp, _Args...>,
__is_nt_constructible_impl<_Tp, _Args...>>::type
{ };
template<typename _Tp, bool = __is_referenceable<_Tp>::value>
struct __is_nothrow_copy_constructible_impl;
template<typename _Tp>
struct __is_nothrow_copy_constructible_impl<_Tp, false>
: public false_type { };
template<typename _Tp>
struct __is_nothrow_copy_constructible_impl<_Tp, true>
: public is_nothrow_constructible<_Tp, const _Tp&>
{ };
/// is_nothrow_copy_constructible
template<typename _Tp>
struct is_nothrow_copy_constructible
: public __is_nothrow_copy_constructible_impl<_Tp>
{ };
template<typename _Tp, bool = __is_referenceable<_Tp>::value>
struct __is_nothrow_move_constructible_impl;
template<typename _Tp>
struct __is_nothrow_move_constructible_impl<_Tp, false>
: public false_type { };
template<typename _Tp>
struct __is_nothrow_move_constructible_impl<_Tp, true>
: public is_nothrow_constructible<_Tp, _Tp&&>
{ };
/// is_nothrow_move_constructible
template<typename _Tp>
struct is_nothrow_move_constructible
: public __is_nothrow_move_constructible_impl<_Tp>
{ };
template<typename _Tp, typename _Up>
class __is_assignable_helper
{
template<typename _Tp1, typename _Up1,
typename = decltype(declval<_Tp1>() = declval<_Up1>())>
static true_type
__test(int);
template<typename, typename>
static false_type
__test(...);
public:
typedef decltype(__test<_Tp, _Up>(0)) type;
};
/// is_assignable
template<typename _Tp, typename _Up>
struct is_assignable
: public __is_assignable_helper<_Tp, _Up>::type
{ };
template<typename _Tp, bool = __is_referenceable<_Tp>::value>
struct __is_copy_assignable_impl;
template<typename _Tp>
struct __is_copy_assignable_impl<_Tp, false>
: public false_type { };
template<typename _Tp>
struct __is_copy_assignable_impl<_Tp, true>
: public is_assignable<_Tp&, const _Tp&>
{ };
/// is_copy_assignable
template<typename _Tp>
struct is_copy_assignable
: public __is_copy_assignable_impl<_Tp>
{ };
template<typename _Tp, bool = __is_referenceable<_Tp>::value>
struct __is_move_assignable_impl;
template<typename _Tp>
struct __is_move_assignable_impl<_Tp, false>
: public false_type { };
template<typename _Tp>
struct __is_move_assignable_impl<_Tp, true>
: public is_assignable<_Tp&, _Tp&&>
{ };
/// is_move_assignable
template<typename _Tp>
struct is_move_assignable
: public __is_move_assignable_impl<_Tp>
{ };
template<typename _Tp, typename _Up>
struct __is_nt_assignable_impl
: public integral_constant<bool, noexcept(declval<_Tp>() = declval<_Up>())>
{ };
/// is_nothrow_assignable
template<typename _Tp, typename _Up>
struct is_nothrow_assignable
: public __and_<is_assignable<_Tp, _Up>,
__is_nt_assignable_impl<_Tp, _Up>>::type
{ };
template<typename _Tp, bool = __is_referenceable<_Tp>::value>
struct __is_nt_copy_assignable_impl;
template<typename _Tp>
struct __is_nt_copy_assignable_impl<_Tp, false>
: public false_type { };
template<typename _Tp>
struct __is_nt_copy_assignable_impl<_Tp, true>
: public is_nothrow_assignable<_Tp&, const _Tp&>
{ };
/// is_nothrow_copy_assignable
template<typename _Tp>
struct is_nothrow_copy_assignable
: public __is_nt_copy_assignable_impl<_Tp>
{ };
template<typename _Tp, bool = __is_referenceable<_Tp>::value>
struct __is_nt_move_assignable_impl;
template<typename _Tp>
struct __is_nt_move_assignable_impl<_Tp, false>
: public false_type { };
template<typename _Tp>
struct __is_nt_move_assignable_impl<_Tp, true>
: public is_nothrow_assignable<_Tp&, _Tp&&>
{ };
/// is_nothrow_move_assignable
template<typename _Tp>
struct is_nothrow_move_assignable
: public __is_nt_move_assignable_impl<_Tp>
{ };
/// is_trivially_constructible (still unimplemented)
/// is_trivially_default_constructible (still unimplemented)
/// is_trivially_copy_constructible (still unimplemented)
/// is_trivially_move_constructible (still unimplemented)
/// is_trivially_assignable (still unimplemented)
/// is_trivially_copy_assignable (still unimplemented)
/// is_trivially_move_assignable (still unimplemented)
/// is_trivially_destructible
template<typename _Tp>
struct is_trivially_destructible
: public __and_<is_destructible<_Tp>, integral_constant<bool,
__has_trivial_destructor(_Tp)>>::type
{ };
/// has_trivial_default_constructor (temporary legacy)
template<typename _Tp>
struct has_trivial_default_constructor
: public integral_constant<bool, __has_trivial_constructor(_Tp)>
{ };
/// has_trivial_copy_constructor (temporary legacy)
template<typename _Tp>
struct has_trivial_copy_constructor
: public integral_constant<bool, __has_trivial_copy(_Tp)>
{ };
/// has_trivial_copy_assign (temporary legacy)
template<typename _Tp>
struct has_trivial_copy_assign
: public integral_constant<bool, __has_trivial_assign(_Tp)>
{ };
/// has_virtual_destructor
template<typename _Tp>
struct has_virtual_destructor
: public integral_constant<bool, __has_virtual_destructor(_Tp)>
{ };
// type property queries.
/// 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>
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>
{ };
// Type relations.
/// is_same
template<typename, typename>
struct is_same
: public false_type { };
template<typename _Tp>
struct is_same<_Tp, _Tp>
: public true_type { };
/// is_base_of
template<typename _Base, typename _Derived>
struct is_base_of
: public integral_constant<bool, __is_base_of(_Base, _Derived)>
{ };
template<typename _From, typename _To,
bool = __or_<is_void<_From>, is_function<_To>,
is_array<_To>>::value>
struct __is_convertible_helper
{ typedef typename is_void<_To>::type type; };
template<typename _From, typename _To>
class __is_convertible_helper<_From, _To, false>
{
template<typename _To1>
static void __test_aux(_To1);
template<typename _From1, typename _To1,
typename = decltype(__test_aux<_To1>(std::declval<_From1>()))>
static true_type
__test(int);
template<typename, typename>
static false_type
__test(...);
public:
typedef decltype(__test<_From, _To>(0)) type;
};
/// is_convertible
template<typename _From, typename _To>
struct is_convertible
: public __is_convertible_helper<_From, _To>::type
{ };
// Const-volatile modifications.
/// 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;
};
#if __cplusplus > 201103L
/// Alias template for remove_const
template<typename _Tp>
using remove_const_t = typename remove_const<_Tp>::type;
/// Alias template for remove_volatile
template<typename _Tp>
using remove_volatile_t = typename remove_volatile<_Tp>::type;
/// Alias template for remove_cv
template<typename _Tp>
using remove_cv_t = typename remove_cv<_Tp>::type;
/// Alias template for add_const
template<typename _Tp>
using add_const_t = typename add_const<_Tp>::type;
/// Alias template for add_volatile
template<typename _Tp>
using add_volatile_t = typename add_volatile<_Tp>::type;
/// Alias template for add_cv
template<typename _Tp>
using add_cv_t = typename add_cv<_Tp>::type;
#endif
// Reference transformations.
/// remove_reference
template<typename _Tp>
struct remove_reference
{ typedef _Tp type; };
template<typename _Tp>
struct remove_reference<_Tp&>
{ typedef _Tp type; };
template<typename _Tp>
struct remove_reference<_Tp&&>
{ typedef _Tp type; };
template<typename _Tp, bool = __is_referenceable<_Tp>::value>
struct __add_lvalue_reference_helper
{ typedef _Tp type; };
template<typename _Tp>
struct __add_lvalue_reference_helper<_Tp, true>
{ typedef _Tp& type; };
/// add_lvalue_reference
template<typename _Tp>
struct add_lvalue_reference
: public __add_lvalue_reference_helper<_Tp>
{ };
template<typename _Tp, bool = __is_referenceable<_Tp>::value>
struct __add_rvalue_reference_helper
{ typedef _Tp type; };
template<typename _Tp>
struct __add_rvalue_reference_helper<_Tp, true>
{ typedef _Tp&& type; };
/// add_rvalue_reference
template<typename _Tp>
struct add_rvalue_reference
: public __add_rvalue_reference_helper<_Tp>
{ };
#if __cplusplus > 201103L
/// Alias template for remove_reference
template<typename _Tp>
using remove_reference_t = typename remove_reference<_Tp>::type;
/// Alias template for add_lvalue_reference
template<typename _Tp>
using add_lvalue_reference_t = typename add_lvalue_reference<_Tp>::type;
/// Alias template for add_rvalue_reference
template<typename _Tp>
using add_rvalue_reference_t = typename add_rvalue_reference<_Tp>::type;
#endif
// Sign modifications.
// Utility for constructing identically cv-qualified types.
template<typename _Unqualified, bool _IsConst, bool _IsVol>
struct __cv_selector;
template<typename _Unqualified>
struct __cv_selector<_Unqualified, false, false>
{ typedef _Unqualified __type; };
template<typename _Unqualified>
struct __cv_selector<_Unqualified, false, true>
{ typedef volatile _Unqualified __type; };
template<typename _Unqualified>
struct __cv_selector<_Unqualified, true, false>
{ typedef const _Unqualified __type; };
template<typename _Unqualified>
struct __cv_selector<_Unqualified, true, true>
{ typedef const volatile _Unqualified __type; };
template<typename _Qualified, typename _Unqualified,
bool _IsConst = is_const<_Qualified>::value,
bool _IsVol = is_volatile<_Qualified>::value>
class __match_cv_qualifiers
{
typedef __cv_selector<_Unqualified, _IsConst, _IsVol> __match;
public:
typedef typename __match::__type __type;
};
// Utility for finding the unsigned versions of signed integral types.
template<typename _Tp>
struct __make_unsigned
{ typedef _Tp __type; };
template<>
struct __make_unsigned<char>
{ typedef unsigned char __type; };
template<>
struct __make_unsigned<signed char>
{ typedef unsigned char __type; };
template<>
struct __make_unsigned<short>
{ typedef unsigned short __type; };
template<>
struct __make_unsigned<int>
{ typedef unsigned int __type; };
template<>
struct __make_unsigned<long>
{ typedef unsigned long __type; };
template<>
struct __make_unsigned<long long>
{ typedef unsigned long long __type; };
#if !defined(__STRICT_ANSI__) && defined(_GLIBCXX_USE_INT128)
template<>
struct __make_unsigned<__int128>
{ typedef unsigned __int128 __type; };
#endif
// Select between integral and enum: not possible to be both.
template<typename _Tp,
bool _IsInt = is_integral<_Tp>::value,
bool _IsEnum = is_enum<_Tp>::value>
class __make_unsigned_selector;
template<typename _Tp>
class __make_unsigned_selector<_Tp, true, false>
{
typedef __make_unsigned<typename remove_cv<_Tp>::type> __unsignedt;
typedef typename __unsignedt::__type __unsigned_type;
typedef __match_cv_qualifiers<_Tp, __unsigned_type> __cv_unsigned;
public:
typedef typename __cv_unsigned::__type __type;
};
template<typename _Tp>
class __make_unsigned_selector<_Tp, false, true>
{
// With -fshort-enums, an enum may be as small as a char.
typedef unsigned char __smallest;
static const bool __b0 = sizeof(_Tp) <= sizeof(__smallest);
static const bool __b1 = sizeof(_Tp) <= sizeof(unsigned short);
static const bool __b2 = sizeof(_Tp) <= sizeof(unsigned int);
typedef conditional<__b2, unsigned int, unsigned long> __cond2;
typedef typename __cond2::type __cond2_type;
typedef conditional<__b1, unsigned short, __cond2_type> __cond1;
typedef typename __cond1::type __cond1_type;
public:
typedef typename conditional<__b0, __smallest, __cond1_type>::type __type;
};
// Given an integral/enum type, return the corresponding unsigned
// integer type.
// Primary template.
/// make_unsigned
template<typename _Tp>
struct make_unsigned
{ typedef typename __make_unsigned_selector<_Tp>::__type type; };
// Integral, but don't define.
template<>
struct make_unsigned<bool>;
// Utility for finding the signed versions of unsigned integral types.
template<typename _Tp>
struct __make_signed
{ typedef _Tp __type; };
template<>
struct __make_signed<char>
{ typedef signed char __type; };
template<>
struct __make_signed<unsigned char>
{ typedef signed char __type; };
template<>
struct __make_signed<unsigned short>
{ typedef signed short __type; };
template<>
struct __make_signed<unsigned int>
{ typedef signed int __type; };
template<>
struct __make_signed<unsigned long>
{ typedef signed long __type; };
template<>
struct __make_signed<unsigned long long>
{ typedef signed long long __type; };
#if !defined(__STRICT_ANSI__) && defined(_GLIBCXX_USE_INT128)
template<>
struct __make_signed<unsigned __int128>
{ typedef __int128 __type; };
#endif
// Select between integral and enum: not possible to be both.
template<typename _Tp,
bool _IsInt = is_integral<_Tp>::value,
bool _IsEnum = is_enum<_Tp>::value>
class __make_signed_selector;
template<typename _Tp>
class __make_signed_selector<_Tp, true, false>
{
typedef __make_signed<typename remove_cv<_Tp>::type> __signedt;
typedef typename __signedt::__type __signed_type;
typedef __match_cv_qualifiers<_Tp, __signed_type> __cv_signed;
public:
typedef typename __cv_signed::__type __type;
};
template<typename _Tp>
class __make_signed_selector<_Tp, false, true>
{
// With -fshort-enums, an enum may be as small as a char.
typedef signed char __smallest;
static const bool __b0 = sizeof(_Tp) <= sizeof(__smallest);
static const bool __b1 = sizeof(_Tp) <= sizeof(signed short);
static const bool __b2 = sizeof(_Tp) <= sizeof(signed int);
typedef conditional<__b2, signed int, signed long> __cond2;
typedef typename __cond2::type __cond2_type;
typedef conditional<__b1, signed short, __cond2_type> __cond1;
typedef typename __cond1::type __cond1_type;
public:
typedef typename conditional<__b0, __smallest, __cond1_type>::type __type;
};
// Given an integral/enum type, return the corresponding signed
// integer type.
// Primary template.
/// make_signed
template<typename _Tp>
struct make_signed
{ typedef typename __make_signed_selector<_Tp>::__type type; };
// Integral, but don't define.
template<>
struct make_signed<bool>;
#if __cplusplus > 201103L
/// Alias template for make_signed
template<typename _Tp>
using make_signed_t = typename make_signed<_Tp>::type;
/// Alias template for make_unsigned
template<typename _Tp>
using make_unsigned_t = typename make_unsigned<_Tp>::type;
#endif
// Array modifications.
/// 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; };
#if __cplusplus > 201103L
/// Alias template for remove_extent
template<typename _Tp>
using remove_extent_t = typename remove_extent<_Tp>::type;
/// Alias template for remove_all_extents
template<typename _Tp>
using remove_all_extents_t = typename remove_all_extents<_Tp>::type;
#endif
// Pointer modifications.
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>
{ };
/// add_pointer
template<typename _Tp, bool = __or_<__is_referenceable<_Tp>,
is_void<_Tp>>::value>
struct __add_pointer_helper
{ typedef _Tp type; };
template<typename _Tp>
struct __add_pointer_helper<_Tp, true>
{ typedef typename remove_reference<_Tp>::type* type; };
template<typename _Tp>
struct add_pointer
: public __add_pointer_helper<_Tp>
{ };
#if __cplusplus > 201103L
/// Alias template for remove_pointer
template<typename _Tp>
using remove_pointer_t = typename remove_pointer<_Tp>::type;
/// Alias template for add_pointer
template<typename _Tp>
using add_pointer_t = typename add_pointer<_Tp>::type;
#endif
template<std::size_t _Len>
struct __aligned_storage_msa
{
union __type
{
unsigned char __data[_Len];
struct __attribute__((__aligned__)) { } __align;
};
};
/**
* @brief Alignment type.
*
* The value of _Align is a default-alignment which shall be the
* most stringent alignment requirement for any C++ object type
* whose size is no greater than _Len (3.9). The member typedef
* type shall be a POD type suitable for use as uninitialized
* storage for any object whose size is at most _Len and whose
* alignment is a divisor of _Align.
*/
template<std::size_t _Len, std::size_t _Align =
__alignof__(typename __aligned_storage_msa<_Len>::__type)>
struct aligned_storage
{
union type
{
unsigned char __data[_Len];
struct __attribute__((__aligned__((_Align)))) { } __align;
};
};
// Decay trait for arrays and functions, used for perfect forwarding
// in make_pair, make_tuple, etc.
template<typename _Up,
bool _IsArray = is_array<_Up>::value,
bool _IsFunction = is_function<_Up>::value>
struct __decay_selector;
// NB: DR 705.
template<typename _Up>
struct __decay_selector<_Up, false, false>
{ typedef typename remove_cv<_Up>::type __type; };
template<typename _Up>
struct __decay_selector<_Up, true, false>
{ typedef typename remove_extent<_Up>::type* __type; };
template<typename _Up>
struct __decay_selector<_Up, false, true>
{ typedef typename add_pointer<_Up>::type __type; };
/// decay
template<typename _Tp>
class decay
{
typedef typename remove_reference<_Tp>::type __remove_type;
public:
typedef typename __decay_selector<__remove_type>::__type type;
};
template<typename _Tp>
class reference_wrapper;
// Helper which adds a reference to a type when given a reference_wrapper
template<typename _Tp>
struct __strip_reference_wrapper
{
typedef _Tp __type;
};
template<typename _Tp>
struct __strip_reference_wrapper<reference_wrapper<_Tp> >
{
typedef _Tp& __type;
};
template<typename _Tp>
struct __decay_and_strip
{
typedef typename __strip_reference_wrapper<
typename decay<_Tp>::type>::__type __type;
};
// Primary template.
/// Define a member typedef @c type only if a boolean constant is true.
template<bool, typename _Tp = void>
struct enable_if
{ };
// Partial specialization for true.
template<typename _Tp>
struct enable_if<true, _Tp>
{ typedef _Tp type; };
template<typename... _Cond>
using _Require = typename enable_if<__and_<_Cond...>::value>::type;
// Primary template.
/// Define a member typedef @c type to one of two argument types.
template<bool _Cond, typename _Iftrue, typename _Iffalse>
struct conditional
{ typedef _Iftrue type; };
// Partial specialization for false.
template<typename _Iftrue, typename _Iffalse>
struct conditional<false, _Iftrue, _Iffalse>
{ typedef _Iffalse type; };
/// common_type
template<typename... _Tp>
struct common_type;
// Sfinae-friendly common_type implementation:
struct __do_common_type_impl
{
template<typename _Tp, typename _Up>
static __success_type<typename decay<decltype
(true ? std::declval<_Tp>()
: std::declval<_Up>())>::type> _S_test(int);
template<typename, typename>
static __failure_type _S_test(...);
};
template<typename _Tp, typename _Up>
struct __common_type_impl
: private __do_common_type_impl
{
typedef decltype(_S_test<_Tp, _Up>(0)) type;
};
struct __do_member_type_wrapper
{
template<typename _Tp>
static __success_type<typename _Tp::type> _S_test(int);
template<typename>
static __failure_type _S_test(...);
};
template<typename _Tp>
struct __member_type_wrapper
: private __do_member_type_wrapper
{
typedef decltype(_S_test<_Tp>(0)) type;
};
template<typename _CTp, typename... _Args>
struct __expanded_common_type_wrapper
{
typedef common_type<typename _CTp::type, _Args...> type;
};
template<typename... _Args>
struct __expanded_common_type_wrapper<__failure_type, _Args...>
{ typedef __failure_type type; };
template<typename _Tp>
struct common_type<_Tp>
{ typedef typename decay<_Tp>::type type; };
template<typename _Tp, typename _Up>
struct common_type<_Tp, _Up>
: public __common_type_impl<_Tp, _Up>::type
{ };
template<typename _Tp, typename _Up, typename... _Vp>
struct common_type<_Tp, _Up, _Vp...>
: public __expanded_common_type_wrapper<typename __member_type_wrapper<
common_type<_Tp, _Up>>::type, _Vp...>::type
{ };
/// The underlying type of an enum.
template<typename _Tp>
struct underlying_type
{
typedef __underlying_type(_Tp) type;
};
template<typename _Tp>
struct __declval_protector
{
static const bool __stop = false;
static typename add_rvalue_reference<_Tp>::type __delegate();
};
template<typename _Tp>
inline typename add_rvalue_reference<_Tp>::type
declval() noexcept
{
static_assert(__declval_protector<_Tp>::__stop,
"declval() must not be used!");
return __declval_protector<_Tp>::__delegate();
}
/// result_of
template<typename _Signature>
class result_of;
// Sfinae-friendly result_of implementation:
// [func.require] paragraph 1 bullet 1:
struct __result_of_memfun_ref_impl
{
template<typename _Fp, typename _Tp1, typename... _Args>
static __success_type<decltype(
(std::declval<_Tp1>().*std::declval<_Fp>())(std::declval<_Args>()...)
)> _S_test(int);
template<typename...>
static __failure_type _S_test(...);
};
template<typename _MemPtr, typename _Arg, typename... _Args>
struct __result_of_memfun_ref
: private __result_of_memfun_ref_impl
{
typedef decltype(_S_test<_MemPtr, _Arg, _Args...>(0)) type;
};
// [func.require] paragraph 1 bullet 2:
struct __result_of_memfun_deref_impl
{
template<typename _Fp, typename _Tp1, typename... _Args>
static __success_type<decltype(
((*std::declval<_Tp1>()).*std::declval<_Fp>())(std::declval<_Args>()...)
)> _S_test(int);
template<typename...>
static __failure_type _S_test(...);
};
template<typename _MemPtr, typename _Arg, typename... _Args>
struct __result_of_memfun_deref
: private __result_of_memfun_deref_impl
{
typedef decltype(_S_test<_MemPtr, _Arg, _Args...>(0)) type;
};
// [func.require] paragraph 1 bullet 3:
struct __result_of_memobj_ref_impl
{
template<typename _Fp, typename _Tp1>
static __success_type<decltype(
std::declval<_Tp1>().*std::declval<_Fp>()
)> _S_test(int);
template<typename, typename>
static __failure_type _S_test(...);
};
template<typename _MemPtr, typename _Arg>
struct __result_of_memobj_ref
: private __result_of_memobj_ref_impl
{
typedef decltype(_S_test<_MemPtr, _Arg>(0)) type;
};
// [func.require] paragraph 1 bullet 4:
struct __result_of_memobj_deref_impl
{
template<typename _Fp, typename _Tp1>
static __success_type<decltype(
(*std::declval<_Tp1>()).*std::declval<_Fp>()
)> _S_test(int);
template<typename, typename>
static __failure_type _S_test(...);
};
template<typename _MemPtr, typename _Arg>
struct __result_of_memobj_deref
: private __result_of_memobj_deref_impl
{
typedef decltype(_S_test<_MemPtr, _Arg>(0)) type;
};
template<typename _MemPtr, typename _Arg>
struct __result_of_memobj;
template<typename _Res, typename _Class, typename _Arg>
struct __result_of_memobj<_Res _Class::*, _Arg>
{
typedef typename remove_cv<typename remove_reference<
_Arg>::type>::type _Argval;
typedef _Res _Class::* _MemPtr;
typedef typename conditional<__or_<is_same<_Argval, _Class>,
is_base_of<_Class, _Argval>>::value,
__result_of_memobj_ref<_MemPtr, _Arg>,
__result_of_memobj_deref<_MemPtr, _Arg>
>::type::type type;
};
template<typename _MemPtr, typename _Arg, typename... _Args>
struct __result_of_memfun;
template<typename _Res, typename _Class, typename _Arg, typename... _Args>
struct __result_of_memfun<_Res _Class::*, _Arg, _Args...>
{
typedef typename remove_cv<typename remove_reference<
_Arg>::type>::type _Argval;
typedef _Res _Class::* _MemPtr;
typedef typename conditional<__or_<is_same<_Argval, _Class>,
is_base_of<_Class, _Argval>>::value,
__result_of_memfun_ref<_MemPtr, _Arg, _Args...>,
__result_of_memfun_deref<_MemPtr, _Arg, _Args...>
>::type::type type;
};
template<bool, bool, typename _Functor, typename... _ArgTypes>
struct __result_of_impl
{
typedef __failure_type type;
};
template<typename _MemPtr, typename _Arg>
struct __result_of_impl<true, false, _MemPtr, _Arg>
: public __result_of_memobj<typename decay<_MemPtr>::type, _Arg>
{ };
template<typename _MemPtr, typename _Arg, typename... _Args>
struct __result_of_impl<false, true, _MemPtr, _Arg, _Args...>
: public __result_of_memfun<typename decay<_MemPtr>::type, _Arg, _Args...>
{ };
// [func.require] paragraph 1 bullet 5:
struct __result_of_other_impl
{
template<typename _Fn, typename... _Args>
static __success_type<decltype(
std::declval<_Fn>()(std::declval<_Args>()...)
)> _S_test(int);
template<typename...>
static __failure_type _S_test(...);
};
template<typename _Functor, typename... _ArgTypes>
struct __result_of_impl<false, false, _Functor, _ArgTypes...>
: private __result_of_other_impl
{
typedef decltype(_S_test<_Functor, _ArgTypes...>(0)) type;
};
template<typename _Functor, typename... _ArgTypes>
struct result_of<_Functor(_ArgTypes...)>
: public __result_of_impl<
is_member_object_pointer<
typename remove_reference<_Functor>::type
>::value,
is_member_function_pointer<
typename remove_reference<_Functor>::type
>::value,
_Functor, _ArgTypes...
>::type
{ };
#if __cplusplus > 201103L
/// Alias template for aligned_storage
template<size_t _Len, size_t _Align =
__alignof__(typename __aligned_storage_msa<_Len>::__type)>
using aligned_storage_t = typename aligned_storage<_Len, _Align>::type;
/// Alias template for decay
template<typename _Tp>
using decay_t = typename decay<_Tp>::type;
/// Alias template for enable_if
template<bool _Cond, typename _Tp = void>
using enable_if_t = typename enable_if<_Cond, _Tp>::type;
/// Alias template for conditional
template<bool _Cond, typename _Iftrue, typename _Iffalse>
using conditional_t = typename conditional<_Cond, _Iftrue, _Iffalse>::type;
/// Alias template for common_type
template<typename... _Tp>
using common_type_t = typename common_type<_Tp...>::type;
/// Alias template for underlying_type
template<typename _Tp>
using underlying_type_t = typename underlying_type<_Tp>::type;
/// Alias template for result_of
template<typename _Tp>
using result_of_t = typename result_of<_Tp>::type;
#endif
/// @} group metaprogramming
/**
* Use SFINAE to determine if the type _Tp has a publicly-accessible
* member type _NTYPE.
*/
#define _GLIBCXX_HAS_NESTED_TYPE(_NTYPE) \
template<typename _Tp> \
class __has_##_NTYPE##_helper \
{ \
template<typename _Up> \
struct _Wrap_type \
{ }; \
\
template<typename _Up> \
static true_type __test(_Wrap_type<typename _Up::_NTYPE>*); \
\
template<typename _Up> \
static false_type __test(...); \
\
public: \
typedef decltype(__test<_Tp>(0)) type; \
}; \
\
template<typename _Tp> \
struct __has_##_NTYPE \
: public __has_##_NTYPE##_helper \
<typename remove_cv<_Tp>::type>::type \
{ };
_GLIBCXX_END_NAMESPACE_VERSION
} // namespace std
#endif // C++11
#endif // _GLIBCXX_TYPE_TRAITS
std::is_null_pointer
is_null_pointer (LWG 2247).
Definition: type_traits:481
std::is_union
is_union
Definition: type_traits:360
std::is_standard_layout
is_standard_layout
Definition: type_traits:596
std::is_member_function_pointer
is_member_function_pointer
Definition: type_traits:347
std::is_compound
is_compound
Definition: type_traits:532
std::is_arithmetic
is_arithmetic
Definition: type_traits:502
c++config.h
std::true_type
integral_constant< bool, true > true_type
The type used as a compile-time boolean with true value.
Definition: type_traits:72
std::is_enum
is_enum
Definition: type_traits:354
std::is_pointer
is_pointer
Definition: type_traits:297
std::is_fundamental
is_fundamental
Definition: type_traits:508
std::is_rvalue_reference
is_rvalue_reference
Definition: type_traits:312
std::is_lvalue_reference
is_lvalue_reference
Definition: type_traits:303
std::is_class
is_class
Definition: type_traits:366
std::is_abstract
is_abstract
Definition: type_traits:627
std::is_floating_point
is_floating_point
Definition: type_traits:270
std::is_member_pointer
is_member_pointer
Definition: type_traits:521
std::is_pod
is_pod
Definition: type_traits:603
std::is_scalar
is_scalar
Definition: type_traits:525
std::is_function
is_function
Definition: type_traits:320
std::is_volatile
is_volatile
Definition: type_traits:579
c++0x_warning.h
std::is_empty
is_empty
Definition: type_traits:615
std::false_type
integral_constant< bool, false > false_type
The type used as a compile-time boolean with false value.
Definition: type_traits:75
std::is_reference
is_reference
Definition: type_traits:495
std::is_literal_type
is_literal_type
Definition: type_traits:609
std::integral_constant
integral_constant
Definition: type_traits:57
std::__is_nullptr_t
__is_nullptr_t (extension).
Definition: type_traits:487
std::is_member_object_pointer
is_member_object_pointer
Definition: type_traits:332
std::is_const
is_const
Definition: type_traits:570
std::is_array
is_array
Definition: type_traits:276
std::is_object
is_object
Definition: type_traits:515
std::is_void
is_void
Definition: type_traits:160
std::is_polymorphic
is_polymorphic
Definition: type_traits:621
std::is_trivial
is_trivial
Definition: type_traits:588
std::is_integral
is_integral
Definition: type_traits:242