1 // -*- C++ -*- 2 //===----------------------------------------------------------------------===// 3 // 4 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 5 // See https://llvm.org/LICENSE.txt for license information. 6 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 7 // 8 //===----------------------------------------------------------------------===// 9 10 #ifndef _LIBCPP___FUNCTIONAL_REFERENCE_WRAPPER_H 11 #define _LIBCPP___FUNCTIONAL_REFERENCE_WRAPPER_H 12 13 #include <__config> 14 #include <__functional/weak_result_type.h> 15 #include <__memory/addressof.h> 16 #include <__utility/forward.h> 17 #include <type_traits> 18 19 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER) 20 #pragma GCC system_header 21 #endif 22 23 _LIBCPP_BEGIN_NAMESPACE_STD 24 25 template <class _Tp> 26 class _LIBCPP_TEMPLATE_VIS reference_wrapper 27 #if _LIBCPP_STD_VER <= 17 || !defined(_LIBCPP_ABI_NO_BINDER_BASES) 28 : public __weak_result_type<_Tp> 29 #endif 30 { 31 public: 32 // types 33 typedef _Tp type; 34 private: 35 type* __f_; 36 37 #ifndef _LIBCPP_CXX03_LANG 38 static void __fun(_Tp&) _NOEXCEPT; 39 static void __fun(_Tp&&) = delete; 40 #endif 41 42 public: 43 // construct/copy/destroy 44 #ifdef _LIBCPP_CXX03_LANG 45 _LIBCPP_INLINE_VISIBILITY 46 reference_wrapper(type& __f) _NOEXCEPT 47 : __f_(_VSTD::addressof(__f)) {} 48 #else 49 template <class _Up, class = _EnableIf<!__is_same_uncvref<_Up, reference_wrapper>::value, decltype(__fun(declval<_Up>())) >> 50 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17 51 reference_wrapper(_Up&& __u) _NOEXCEPT_(noexcept(__fun(declval<_Up>()))) { 52 type& __f = static_cast<_Up&&>(__u); 53 __f_ = _VSTD::addressof(__f); 54 } 55 #endif 56 57 // access 58 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17 59 operator type&() const _NOEXCEPT {return *__f_;} 60 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17 61 type& get() const _NOEXCEPT {return *__f_;} 62 63 #ifndef _LIBCPP_CXX03_LANG 64 // invoke 65 template <class... _ArgTypes> 66 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17 67 typename __invoke_of<type&, _ArgTypes...>::type 68 operator() (_ArgTypes&&... __args) const { 69 return _VSTD::__invoke(get(), _VSTD::forward<_ArgTypes>(__args)...); 70 } 71 #else 72 73 _LIBCPP_INLINE_VISIBILITY 74 typename __invoke_return<type>::type 75 operator() () const { 76 return _VSTD::__invoke(get()); 77 } 78 79 template <class _A0> 80 _LIBCPP_INLINE_VISIBILITY 81 typename __invoke_return0<type, _A0>::type 82 operator() (_A0& __a0) const { 83 return _VSTD::__invoke(get(), __a0); 84 } 85 86 template <class _A0> 87 _LIBCPP_INLINE_VISIBILITY 88 typename __invoke_return0<type, _A0 const>::type 89 operator() (_A0 const& __a0) const { 90 return _VSTD::__invoke(get(), __a0); 91 } 92 93 template <class _A0, class _A1> 94 _LIBCPP_INLINE_VISIBILITY 95 typename __invoke_return1<type, _A0, _A1>::type 96 operator() (_A0& __a0, _A1& __a1) const { 97 return _VSTD::__invoke(get(), __a0, __a1); 98 } 99 100 template <class _A0, class _A1> 101 _LIBCPP_INLINE_VISIBILITY 102 typename __invoke_return1<type, _A0 const, _A1>::type 103 operator() (_A0 const& __a0, _A1& __a1) const { 104 return _VSTD::__invoke(get(), __a0, __a1); 105 } 106 107 template <class _A0, class _A1> 108 _LIBCPP_INLINE_VISIBILITY 109 typename __invoke_return1<type, _A0, _A1 const>::type 110 operator() (_A0& __a0, _A1 const& __a1) const { 111 return _VSTD::__invoke(get(), __a0, __a1); 112 } 113 114 template <class _A0, class _A1> 115 _LIBCPP_INLINE_VISIBILITY 116 typename __invoke_return1<type, _A0 const, _A1 const>::type 117 operator() (_A0 const& __a0, _A1 const& __a1) const { 118 return _VSTD::__invoke(get(), __a0, __a1); 119 } 120 121 template <class _A0, class _A1, class _A2> 122 _LIBCPP_INLINE_VISIBILITY 123 typename __invoke_return2<type, _A0, _A1, _A2>::type 124 operator() (_A0& __a0, _A1& __a1, _A2& __a2) const { 125 return _VSTD::__invoke(get(), __a0, __a1, __a2); 126 } 127 128 template <class _A0, class _A1, class _A2> 129 _LIBCPP_INLINE_VISIBILITY 130 typename __invoke_return2<type, _A0 const, _A1, _A2>::type 131 operator() (_A0 const& __a0, _A1& __a1, _A2& __a2) const { 132 return _VSTD::__invoke(get(), __a0, __a1, __a2); 133 } 134 135 template <class _A0, class _A1, class _A2> 136 _LIBCPP_INLINE_VISIBILITY 137 typename __invoke_return2<type, _A0, _A1 const, _A2>::type 138 operator() (_A0& __a0, _A1 const& __a1, _A2& __a2) const { 139 return _VSTD::__invoke(get(), __a0, __a1, __a2); 140 } 141 142 template <class _A0, class _A1, class _A2> 143 _LIBCPP_INLINE_VISIBILITY 144 typename __invoke_return2<type, _A0, _A1, _A2 const>::type 145 operator() (_A0& __a0, _A1& __a1, _A2 const& __a2) const { 146 return _VSTD::__invoke(get(), __a0, __a1, __a2); 147 } 148 149 template <class _A0, class _A1, class _A2> 150 _LIBCPP_INLINE_VISIBILITY 151 typename __invoke_return2<type, _A0 const, _A1 const, _A2>::type 152 operator() (_A0 const& __a0, _A1 const& __a1, _A2& __a2) const { 153 return _VSTD::__invoke(get(), __a0, __a1, __a2); 154 } 155 156 template <class _A0, class _A1, class _A2> 157 _LIBCPP_INLINE_VISIBILITY 158 typename __invoke_return2<type, _A0 const, _A1, _A2 const>::type 159 operator() (_A0 const& __a0, _A1& __a1, _A2 const& __a2) const { 160 return _VSTD::__invoke(get(), __a0, __a1, __a2); 161 } 162 163 template <class _A0, class _A1, class _A2> 164 _LIBCPP_INLINE_VISIBILITY 165 typename __invoke_return2<type, _A0, _A1 const, _A2 const>::type 166 operator() (_A0& __a0, _A1 const& __a1, _A2 const& __a2) const { 167 return _VSTD::__invoke(get(), __a0, __a1, __a2); 168 } 169 170 template <class _A0, class _A1, class _A2> 171 _LIBCPP_INLINE_VISIBILITY 172 typename __invoke_return2<type, _A0 const, _A1 const, _A2 const>::type 173 operator() (_A0 const& __a0, _A1 const& __a1, _A2 const& __a2) const { 174 return _VSTD::__invoke(get(), __a0, __a1, __a2); 175 } 176 #endif // _LIBCPP_CXX03_LANG 177 }; 178 179 #ifndef _LIBCPP_HAS_NO_DEDUCTION_GUIDES 180 template <class _Tp> 181 reference_wrapper(_Tp&) -> reference_wrapper<_Tp>; 182 #endif 183 184 template <class _Tp> 185 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17 186 reference_wrapper<_Tp> 187 ref(_Tp& __t) _NOEXCEPT 188 { 189 return reference_wrapper<_Tp>(__t); 190 } 191 192 template <class _Tp> 193 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17 194 reference_wrapper<_Tp> 195 ref(reference_wrapper<_Tp> __t) _NOEXCEPT 196 { 197 return _VSTD::ref(__t.get()); 198 } 199 200 template <class _Tp> 201 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17 202 reference_wrapper<const _Tp> 203 cref(const _Tp& __t) _NOEXCEPT 204 { 205 return reference_wrapper<const _Tp>(__t); 206 } 207 208 template <class _Tp> 209 inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17 210 reference_wrapper<const _Tp> 211 cref(reference_wrapper<_Tp> __t) _NOEXCEPT 212 { 213 return _VSTD::cref(__t.get()); 214 } 215 216 #ifndef _LIBCPP_CXX03_LANG 217 template <class _Tp> void ref(const _Tp&&) = delete; 218 template <class _Tp> void cref(const _Tp&&) = delete; 219 #endif 220 221 _LIBCPP_END_NAMESPACE_STD 222 223 #endif // _LIBCPP___FUNCTIONAL_REFERENCE_WRAPPER_H 224