// C++11 -*- C++ -*- // Copyright (C) 2007-2013 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 // . /** @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 #else #include 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 struct integral_constant { static constexpr _Tp value = __v; typedef _Tp value_type; typedef integral_constant<_Tp, __v> type; constexpr operator value_type() { return value; } }; template constexpr _Tp integral_constant<_Tp, __v>::value; /// The type used as a compile-time boolean with true value. typedef integral_constant true_type; /// The type used as a compile-time boolean with false value. typedef integral_constant false_type; // Meta programming helper types. template struct conditional; template struct __or_; template<> struct __or_<> : public false_type { }; template struct __or_<_B1> : public _B1 { }; template struct __or_<_B1, _B2> : public conditional<_B1::value, _B1, _B2>::type { }; template struct __or_<_B1, _B2, _B3, _Bn...> : public conditional<_B1::value, _B1, __or_<_B2, _B3, _Bn...>>::type { }; template struct __and_; template<> struct __and_<> : public true_type { }; template struct __and_<_B1> : public _B1 { }; template struct __and_<_B1, _B2> : public conditional<_B1::value, _B2, _B1>::type { }; template struct __and_<_B1, _B2, _B3, _Bn...> : public conditional<_B1::value, __and_<_B2, _B3, _Bn...>, _B1>::type { }; template struct __not_ : public integral_constant { }; struct __sfinae_types { typedef char __one; typedef struct { char __arr[2]; } __two; }; // 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 struct __success_type { typedef _Tp type; }; struct __failure_type { }; // Primary type categories. template struct remove_cv; template struct __is_void_helper : public false_type { }; template<> struct __is_void_helper : public true_type { }; /// is_void template struct is_void : public integral_constant::type>::value)> { }; template struct __is_integral_helper : public false_type { }; template<> struct __is_integral_helper : public true_type { }; template<> struct __is_integral_helper : public true_type { }; template<> struct __is_integral_helper : public true_type { }; template<> struct __is_integral_helper : public true_type { }; #ifdef _GLIBCXX_USE_WCHAR_T template<> struct __is_integral_helper : public true_type { }; #endif template<> struct __is_integral_helper : public true_type { }; template<> struct __is_integral_helper : public true_type { }; template<> struct __is_integral_helper : public true_type { }; template<> struct __is_integral_helper : public true_type { }; template<> struct __is_integral_helper : public true_type { }; template<> struct __is_integral_helper : public true_type { }; template<> struct __is_integral_helper : public true_type { }; template<> struct __is_integral_helper : public true_type { }; template<> struct __is_integral_helper : public true_type { }; template<> struct __is_integral_helper : 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 : public true_type { }; #endif /// is_integral template struct is_integral : public integral_constant::type>::value)> { }; template struct __is_floating_point_helper : public false_type { }; template<> struct __is_floating_point_helper : public true_type { }; template<> struct __is_floating_point_helper : public true_type { }; template<> struct __is_floating_point_helper : public true_type { }; #if !defined(__STRICT_ANSI__) && defined(_GLIBCXX_USE_FLOAT128) && (!defined(__clang__) || __clang_major__ > 3 || (__clang_major__ == 3 && __clang_minor__ >= 4)) template<> struct __is_floating_point_helper<__float128> : public true_type { }; #endif /// is_floating_point template struct is_floating_point : public integral_constant::type>::value)> { }; /// is_array template struct is_array : public false_type { }; template struct is_array<_Tp[_Size]> : public true_type { }; template struct is_array<_Tp[]> : public true_type { }; template struct __is_pointer_helper : public false_type { }; template struct __is_pointer_helper<_Tp*> : public true_type { }; /// is_pointer template struct is_pointer : public integral_constant::type>::value)> { }; /// is_lvalue_reference template struct is_lvalue_reference : public false_type { }; template struct is_lvalue_reference<_Tp&> : public true_type { }; /// is_rvalue_reference template struct is_rvalue_reference : public false_type { }; template struct is_rvalue_reference<_Tp&&> : public true_type { }; template struct is_function; template struct __is_member_object_pointer_helper : public false_type { }; template struct __is_member_object_pointer_helper<_Tp _Cp::*> : public integral_constant::value> { }; /// is_member_object_pointer template struct is_member_object_pointer : public integral_constant::type>::value)> { }; template struct __is_member_function_pointer_helper : public false_type { }; template struct __is_member_function_pointer_helper<_Tp _Cp::*> : public integral_constant::value> { }; /// is_member_function_pointer template struct is_member_function_pointer : public integral_constant::type>::value)> { }; /// is_enum template struct is_enum : public integral_constant { }; /// is_union template struct is_union : public integral_constant { }; /// is_class template struct is_class : public integral_constant { }; /// is_function template struct is_function : public false_type { }; template struct is_function<_Res(_ArgTypes...)> : public true_type { }; template struct is_function<_Res(_ArgTypes......)> : public true_type { }; template struct is_function<_Res(_ArgTypes...) const> : public true_type { }; template struct is_function<_Res(_ArgTypes......) const> : public true_type { }; template struct is_function<_Res(_ArgTypes...) volatile> : public true_type { }; template struct is_function<_Res(_ArgTypes......) volatile> : public true_type { }; template struct is_function<_Res(_ArgTypes...) const volatile> : public true_type { }; template struct is_function<_Res(_ArgTypes......) const volatile> : public true_type { }; template struct __is_nullptr_t_helper : public false_type { }; template<> struct __is_nullptr_t_helper : public true_type { }; // __is_nullptr_t (extension). template struct __is_nullptr_t : public integral_constant::type>::value)> { }; // Composite type categories. /// is_reference template struct is_reference : public __or_, is_rvalue_reference<_Tp>>::type { }; /// is_arithmetic template struct is_arithmetic : public __or_, is_floating_point<_Tp>>::type { }; /// is_fundamental template struct is_fundamental : public __or_, is_void<_Tp>, __is_nullptr_t<_Tp>>::type { }; /// is_object template struct is_object : public __not_<__or_, is_reference<_Tp>, is_void<_Tp>>>::type { }; template struct is_member_pointer; /// is_scalar template struct is_scalar : public __or_, is_enum<_Tp>, is_pointer<_Tp>, is_member_pointer<_Tp>, __is_nullptr_t<_Tp>>::type { }; /// is_compound template struct is_compound : public integral_constant::value> { }; template struct __is_member_pointer_helper : public false_type { }; template struct __is_member_pointer_helper<_Tp _Cp::*> : public true_type { }; /// is_member_pointer template struct is_member_pointer : public integral_constant::type>::value)> { }; // Type properties. /// is_const template struct is_const : public false_type { }; template struct is_const<_Tp const> : public true_type { }; /// is_volatile template struct is_volatile : public false_type { }; template struct is_volatile<_Tp volatile> : public true_type { }; /// is_trivial template struct is_trivial : public integral_constant { }; // is_trivially_copyable (still unimplemented) /// is_standard_layout template struct is_standard_layout : public integral_constant { }; /// is_pod // Could use is_standard_layout && is_trivial instead of the builtin. template struct is_pod : public integral_constant { }; /// is_literal_type template struct is_literal_type : public integral_constant { }; /// is_empty template struct is_empty : public integral_constant { }; /// is_polymorphic template struct is_polymorphic : public integral_constant { }; /// is_abstract template struct is_abstract : public integral_constant { }; template::value, bool = is_floating_point<_Tp>::value> struct __is_signed_helper : public false_type { }; template struct __is_signed_helper<_Tp, false, true> : public true_type { }; template struct __is_signed_helper<_Tp, true, false> : public integral_constant(_Tp(-1) < _Tp(0))> { }; /// is_signed template struct is_signed : public integral_constant::value> { }; /// is_unsigned template struct is_unsigned : public __and_, __not_>>::type { }; // Destructible and constructible type properties. template struct add_rvalue_reference; /** * @brief Utility to simplify expressions used in unevaluated operands * @ingroup utilities */ template typename add_rvalue_reference<_Tp>::type declval() noexcept; template struct extent; template struct remove_all_extents; template struct __is_array_known_bounds : public integral_constant::value > 0)> { }; template struct __is_array_unknown_bounds : public __and_, __not_>>::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().~_Tp())> static true_type __test(int); template static false_type __test(...); }; template struct __is_destructible_impl : public __do_is_destructible_impl { typedef decltype(__test<_Tp>(0)) type; }; template, __is_array_unknown_bounds<_Tp>, is_function<_Tp>>::value, bool = __or_, is_scalar<_Tp>>::value> struct __is_destructible_safe; template struct __is_destructible_safe<_Tp, false, false> : public __is_destructible_impl::type>::type { }; template struct __is_destructible_safe<_Tp, true, false> : public false_type { }; template struct __is_destructible_safe<_Tp, false, true> : public true_type { }; /// is_destructible template struct is_destructible : public integral_constant::value)> { }; // 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 static integral_constant().~_Tp())> __test(int); template static false_type __test(...); }; template struct __is_nt_destructible_impl : public __do_is_nt_destructible_impl { typedef decltype(__test<_Tp>(0)) type; }; template, __is_array_unknown_bounds<_Tp>, is_function<_Tp>>::value, bool = __or_, is_scalar<_Tp>>::value> struct __is_nt_destructible_safe; template struct __is_nt_destructible_safe<_Tp, false, false> : public __is_nt_destructible_impl::type>::type { }; template struct __is_nt_destructible_safe<_Tp, true, false> : public false_type { }; template struct __is_nt_destructible_safe<_Tp, false, true> : public true_type { }; /// is_nothrow_destructible template struct is_nothrow_destructible : public integral_constant::value)> { }; struct __do_is_default_constructible_impl { template static true_type __test(int); template static false_type __test(...); }; template struct __is_default_constructible_impl : public __do_is_default_constructible_impl { typedef decltype(__test<_Tp>(0)) type; }; template struct __is_default_constructible_atom : public __and_<__not_>, __is_default_constructible_impl<_Tp>>::type { }; template::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 struct __is_default_constructible_safe<_Tp, true> : public __and_<__is_array_known_bounds<_Tp>, __is_default_constructible_atom::type>>::type { }; template struct __is_default_constructible_safe<_Tp, false> : public __is_default_constructible_atom<_Tp>::type { }; /// is_default_constructible template struct is_default_constructible : public integral_constant::value)> { }; // 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(declval<_From>()))> static true_type __test(int); template static false_type __test(...); }; template struct __is_static_castable_impl : public __do_is_static_castable_impl { typedef decltype(__test<_From, _To>(0)) type; }; template struct __is_static_castable_safe : public __is_static_castable_impl<_From, _To>::type { }; // __is_static_castable template struct __is_static_castable : public integral_constant::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()))> static true_type __test(int); template static false_type __test(...); }; template struct __is_direct_constructible_impl : public __do_is_direct_constructible_impl { typedef decltype(__test<_Tp, _Arg>(0)) type; }; template struct __is_direct_constructible_new_safe : public __and_, __is_direct_constructible_impl<_Tp, _Arg>>::type { }; template struct is_same; template struct is_base_of; template struct remove_reference; template, is_function<_From>>>::value> struct __is_base_to_derived_ref; // Detect whether we have a downcast situation during // reference binding. template struct __is_base_to_derived_ref<_From, _To, true> { typedef typename remove_cv::type>::type __src_t; typedef typename remove_cv::type>::type __dst_t; typedef __and_<__not_>, is_base_of<__src_t, __dst_t>> type; static constexpr bool value = type::value; }; template struct __is_base_to_derived_ref<_From, _To, false> : public false_type { }; template, 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 struct __is_lvalue_to_rvalue_ref<_From, _To, true> { typedef typename remove_cv::type>::type __src_t; typedef typename remove_cv::type>::type __dst_t; typedef __and_<__not_>, __or_, is_base_of<__dst_t, __src_t>>> type; static constexpr bool value = type::value; }; template 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 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 struct __is_direct_constructible_new : public conditional::value, __is_direct_constructible_ref_cast<_Tp, _Arg>, __is_direct_constructible_new_safe<_Tp, _Arg> >::type { }; template struct __is_direct_constructible : public integral_constant::value)> { }; // 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()...))> static true_type __test(int); template static false_type __test(...); }; template struct __is_nary_constructible_impl : public __do_is_nary_constructible_impl { typedef decltype(__test<_Tp, _Args...>(0)) type; }; template struct __is_nary_constructible : public __is_nary_constructible_impl<_Tp, _Args...>::type { static_assert(sizeof...(_Args) > 1, "Only useful for > 1 arguments"); }; template struct __is_constructible_impl : public __is_nary_constructible<_Tp, _Args...> { }; template struct __is_constructible_impl<_Tp, _Arg> : public __is_direct_constructible<_Tp, _Arg> { }; template struct __is_constructible_impl<_Tp> : public is_default_constructible<_Tp> { }; /// is_constructible template struct is_constructible : public integral_constant::value)> { }; template::value> struct __is_copy_constructible_impl; template struct __is_copy_constructible_impl<_Tp, true> : public false_type { }; template struct __is_copy_constructible_impl<_Tp, false> : public is_constructible<_Tp, const _Tp&> { }; /// is_copy_constructible template struct is_copy_constructible : public __is_copy_constructible_impl<_Tp> { }; template::value> struct __is_move_constructible_impl; template struct __is_move_constructible_impl<_Tp, true> : public false_type { }; template struct __is_move_constructible_impl<_Tp, false> : public is_constructible<_Tp, _Tp&&> { }; /// is_move_constructible template struct is_move_constructible : public __is_move_constructible_impl<_Tp> { }; template struct __is_nt_default_constructible_atom : public integral_constant { }; template::value> struct __is_nt_default_constructible_impl; template struct __is_nt_default_constructible_impl<_Tp, true> : public __and_<__is_array_known_bounds<_Tp>, __is_nt_default_constructible_atom::type>>::type { }; template struct __is_nt_default_constructible_impl<_Tp, false> : public __is_nt_default_constructible_atom<_Tp> { }; /// is_nothrow_default_constructible template struct is_nothrow_default_constructible : public __and_, __is_nt_default_constructible_impl<_Tp>>::type { }; template struct __is_nt_constructible_impl : public integral_constant()...))> { }; template struct __is_nt_constructible_impl<_Tp, _Arg> : public integral_constant(declval<_Arg>()))> { }; template struct __is_nt_constructible_impl<_Tp> : public is_nothrow_default_constructible<_Tp> { }; /// is_nothrow_constructible template struct is_nothrow_constructible : public __and_, __is_nt_constructible_impl<_Tp, _Args...>>::type { }; template::value> struct __is_nothrow_copy_constructible_impl; template struct __is_nothrow_copy_constructible_impl<_Tp, true> : public false_type { }; template struct __is_nothrow_copy_constructible_impl<_Tp, false> : public is_nothrow_constructible<_Tp, const _Tp&> { }; /// is_nothrow_copy_constructible template struct is_nothrow_copy_constructible : public __is_nothrow_copy_constructible_impl<_Tp> { }; template::value> struct __is_nothrow_move_constructible_impl; template struct __is_nothrow_move_constructible_impl<_Tp, true> : public false_type { }; template struct __is_nothrow_move_constructible_impl<_Tp, false> : public is_nothrow_constructible<_Tp, _Tp&&> { }; /// is_nothrow_move_constructible template struct is_nothrow_move_constructible : public __is_nothrow_move_constructible_impl<_Tp> { }; template class __is_assignable_helper : public __sfinae_types { template static decltype(declval<_Tp1>() = declval<_Up1>(), __one()) __test(int); template static __two __test(...); public: static constexpr bool value = sizeof(__test<_Tp, _Up>(0)) == 1; }; /// is_assignable template struct is_assignable : public integral_constant::value> { }; template::value> struct __is_copy_assignable_impl; template struct __is_copy_assignable_impl<_Tp, true> : public false_type { }; template struct __is_copy_assignable_impl<_Tp, false> : public is_assignable<_Tp&, const _Tp&> { }; /// is_copy_assignable template struct is_copy_assignable : public __is_copy_assignable_impl<_Tp> { }; template::value> struct __is_move_assignable_impl; template struct __is_move_assignable_impl<_Tp, true> : public false_type { }; template struct __is_move_assignable_impl<_Tp, false> : public is_assignable<_Tp&, _Tp&&> { }; /// is_move_assignable template struct is_move_assignable : public __is_move_assignable_impl<_Tp> { }; template struct __is_nt_assignable_impl : public integral_constant() = declval<_Up>())> { }; /// is_nothrow_assignable template struct is_nothrow_assignable : public __and_, __is_nt_assignable_impl<_Tp, _Up>>::type { }; template::value> struct __is_nt_copy_assignable_impl; template struct __is_nt_copy_assignable_impl<_Tp, true> : public false_type { }; template struct __is_nt_copy_assignable_impl<_Tp, false> : public is_nothrow_assignable<_Tp&, const _Tp&> { }; /// is_nothrow_copy_assignable template struct is_nothrow_copy_assignable : public __is_nt_copy_assignable_impl<_Tp> { }; template::value> struct __is_nt_move_assignable_impl; template struct __is_nt_move_assignable_impl<_Tp, true> : public false_type { }; template struct __is_nt_move_assignable_impl<_Tp, false> : public is_nothrow_assignable<_Tp&, _Tp&&> { }; /// is_nothrow_move_assignable template 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 struct is_trivially_destructible : public __and_, integral_constant>::type { }; /// has_trivial_default_constructor (temporary legacy) template struct has_trivial_default_constructor : public integral_constant { }; /// has_trivial_copy_constructor (temporary legacy) template struct has_trivial_copy_constructor : public integral_constant { }; /// has_trivial_copy_assign (temporary legacy) template struct has_trivial_copy_assign : public integral_constant { }; /// has_virtual_destructor template struct has_virtual_destructor : public integral_constant { }; // type property queries. /// alignment_of template struct alignment_of : public integral_constant { }; /// rank template struct rank : public integral_constant { }; template struct rank<_Tp[_Size]> : public integral_constant::value> { }; template struct rank<_Tp[]> : public integral_constant::value> { }; /// extent template struct extent : public integral_constant { }; template struct extent<_Tp[_Size], _Uint> : public integral_constant::value> { }; template struct extent<_Tp[], _Uint> : public integral_constant::value> { }; // Type relations. /// is_same template struct is_same : public false_type { }; template struct is_same<_Tp, _Tp> : public true_type { }; /// is_base_of template struct is_base_of : public integral_constant { }; template, is_function<_To>, is_array<_To>>::value> struct __is_convertible_helper { static constexpr bool value = is_void<_To>::value; }; template class __is_convertible_helper<_From, _To, false> : public __sfinae_types { template static void __test_aux(_To1); template static decltype(__test_aux<_To1>(std::declval<_From1>()), __one()) __test(int); template static __two __test(...); public: static constexpr bool value = sizeof(__test<_From, _To>(0)) == 1; }; /// is_convertible template struct is_convertible : public integral_constant::value> { }; // Const-volatile modifications. /// remove_const template struct remove_const { typedef _Tp type; }; template struct remove_const<_Tp const> { typedef _Tp type; }; /// remove_volatile template struct remove_volatile { typedef _Tp type; }; template struct remove_volatile<_Tp volatile> { typedef _Tp type; }; /// remove_cv template struct remove_cv { typedef typename remove_const::type>::type type; }; /// add_const template struct add_const { typedef _Tp const type; }; /// add_volatile template struct add_volatile { typedef _Tp volatile type; }; /// add_cv template struct add_cv { typedef typename add_const::type>::type type; }; // Reference transformations. /// remove_reference template struct remove_reference { typedef _Tp type; }; template struct remove_reference<_Tp&> { typedef _Tp type; }; template struct remove_reference<_Tp&&> { typedef _Tp type; }; template>, __not_>>::value, bool = is_rvalue_reference<_Tp>::value> struct __add_lvalue_reference_helper { typedef _Tp type; }; template struct __add_lvalue_reference_helper<_Tp, true, false> { typedef _Tp& type; }; template struct __add_lvalue_reference_helper<_Tp, false, true> { typedef typename remove_reference<_Tp>::type& type; }; /// add_lvalue_reference template struct add_lvalue_reference : public __add_lvalue_reference_helper<_Tp> { }; template>, __not_>>::value> struct __add_rvalue_reference_helper { typedef _Tp type; }; template struct __add_rvalue_reference_helper<_Tp, true> { typedef _Tp&& type; }; /// add_rvalue_reference template struct add_rvalue_reference : public __add_rvalue_reference_helper<_Tp> { }; // Sign modifications. // Utility for constructing identically cv-qualified types. template struct __cv_selector; template struct __cv_selector<_Unqualified, false, false> { typedef _Unqualified __type; }; template struct __cv_selector<_Unqualified, false, true> { typedef volatile _Unqualified __type; }; template struct __cv_selector<_Unqualified, true, false> { typedef const _Unqualified __type; }; template struct __cv_selector<_Unqualified, true, true> { typedef const volatile _Unqualified __type; }; template::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 struct __make_unsigned { typedef _Tp __type; }; template<> struct __make_unsigned { typedef unsigned char __type; }; template<> struct __make_unsigned { typedef unsigned char __type; }; template<> struct __make_unsigned { typedef unsigned short __type; }; template<> struct __make_unsigned { typedef unsigned int __type; }; template<> struct __make_unsigned { typedef unsigned long __type; }; template<> struct __make_unsigned { 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::value, bool _IsEnum = is_enum<_Tp>::value> class __make_unsigned_selector; template class __make_unsigned_selector<_Tp, true, false> { typedef __make_unsigned::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 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 struct make_unsigned { typedef typename __make_unsigned_selector<_Tp>::__type type; }; // Integral, but don't define. template<> struct make_unsigned; // Utility for finding the signed versions of unsigned integral types. template struct __make_signed { typedef _Tp __type; }; template<> struct __make_signed { typedef signed char __type; }; template<> struct __make_signed { typedef signed char __type; }; template<> struct __make_signed { typedef signed short __type; }; template<> struct __make_signed { typedef signed int __type; }; template<> struct __make_signed { typedef signed long __type; }; template<> struct __make_signed { typedef signed long long __type; }; #if !defined(__STRICT_ANSI__) && defined(_GLIBCXX_USE_INT128) template<> struct __make_signed { typedef __int128 __type; }; #endif // Select between integral and enum: not possible to be both. template::value, bool _IsEnum = is_enum<_Tp>::value> class __make_signed_selector; template class __make_signed_selector<_Tp, true, false> { typedef __make_signed::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 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 struct make_signed { typedef typename __make_signed_selector<_Tp>::__type type; }; // Integral, but don't define. template<> struct make_signed; // Array modifications. /// remove_extent template struct remove_extent { typedef _Tp type; }; template struct remove_extent<_Tp[_Size]> { typedef _Tp type; }; template struct remove_extent<_Tp[]> { typedef _Tp type; }; /// remove_all_extents template struct remove_all_extents { typedef _Tp type; }; template struct remove_all_extents<_Tp[_Size]> { typedef typename remove_all_extents<_Tp>::type type; }; template struct remove_all_extents<_Tp[]> { typedef typename remove_all_extents<_Tp>::type type; }; // Pointer modifications. template struct __remove_pointer_helper { typedef _Tp type; }; template struct __remove_pointer_helper<_Tp, _Up*> { typedef _Up type; }; /// remove_pointer template struct remove_pointer : public __remove_pointer_helper<_Tp, typename remove_cv<_Tp>::type> { }; /// add_pointer template struct add_pointer { typedef typename remove_reference<_Tp>::type* type; }; template 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::__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::value, bool _IsFunction = is_function<_Up>::value> struct __decay_selector; // NB: DR 705. template struct __decay_selector<_Up, false, false> { typedef typename remove_cv<_Up>::type __type; }; template struct __decay_selector<_Up, true, false> { typedef typename remove_extent<_Up>::type* __type; }; template struct __decay_selector<_Up, false, true> { typedef typename add_pointer<_Up>::type __type; }; /// decay template class decay { typedef typename remove_reference<_Tp>::type __remove_type; public: typedef typename __decay_selector<__remove_type>::__type type; }; template class reference_wrapper; // Helper which adds a reference to a type when given a reference_wrapper template struct __strip_reference_wrapper { typedef _Tp __type; }; template struct __strip_reference_wrapper > { typedef _Tp& __type; }; template struct __strip_reference_wrapper > { typedef _Tp& __type; }; template 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 struct enable_if { }; // Partial specialization for true. template struct enable_if { typedef _Tp type; }; template using _Require = typename enable_if<__and_<_Cond...>::value>::type; // Primary template. /// Define a member typedef @c type to one of two argument types. template struct conditional { typedef _Iftrue type; }; // Partial specialization for false. template struct conditional { typedef _Iffalse type; }; /// common_type template struct common_type; // Sfinae-friendly common_type implementation: struct __do_common_type_impl { template static __success_type() : std::declval<_Up>())>::type> _S_test(int); template