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The C and C++ Include Header Files
cat -n /usr/include/c++/15/bits/indirect_array.h
1 // The template and inlines for the -*- C++ -*- indirect_array class. 2 3 // Copyright (C) 1997-2025 Free Software Foundation, Inc. 4 // 5 // This file is part of the GNU ISO C++ Library. This library is free 6 // software; you can redistribute it and/or modify it under the 7 // terms of the GNU General Public License as published by the 8 // Free Software Foundation; either version 3, or (at your option) 9 // any later version. 10 11 // This library is distributed in the hope that it will be useful, 12 // but WITHOUT ANY WARRANTY; without even the implied warranty of 13 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 // GNU General Public License for more details. 15 16 // Under Section 7 of GPL version 3, you are granted additional 17 // permissions described in the GCC Runtime Library Exception, version 18 // 3.1, as published by the Free Software Foundation. 19 20 // You should have received a copy of the GNU General Public License and 21 // a copy of the GCC Runtime Library Exception along with this program; 22 // see the files COPYING3 and COPYING.RUNTIME respectively. If not, see 23 // <http://www.gnu.org/licenses/>. 24 25 /** @file bits/indirect_array.h 26 * This is an internal header file, included by other library headers. 27 * Do not attempt to use it directly. @headername{valarray} 28 */ 29 30 // Written by Gabriel Dos Reis <Gabriel.Dos-Reis@DPTMaths.ENS-Cachan.Fr> 31 32 #ifndef _INDIRECT_ARRAY_H 33 #define _INDIRECT_ARRAY_H 1 34 35 #ifdef _GLIBCXX_SYSHDR 36 #pragma GCC system_header 37 #endif 38 39 namespace std _GLIBCXX_VISIBILITY(default) 40 { 41 _GLIBCXX_BEGIN_NAMESPACE_VERSION 42 43 /** 44 * @addtogroup numeric_arrays 45 * @{ 46 */ 47 48 /** 49 * @brief Reference to arbitrary subset of an array. 50 * 51 * An indirect_array is a reference to the actual elements of an array 52 * specified by an ordered array of indices. The way to get an 53 * indirect_array is to call operator[](valarray<size_t>) on a valarray. 54 * The returned indirect_array then permits carrying operations out on the 55 * referenced subset of elements in the original valarray. 56 * 57 * For example, if an indirect_array is obtained using the array (4,2,0) as 58 * an argument, and then assigned to an array containing (1,2,3), then the 59 * underlying array will have array[0]==3, array[2]==2, and array[4]==1. 60 * 61 * @param Tp Element type. 62 */ 63 template <class _Tp> 64 class indirect_array 65 { 66 public: 67 typedef _Tp value_type; 68 69 // _GLIBCXX_RESOLVE_LIB_DEFECTS 70 // 253. valarray helper functions are almost entirely useless 71 72 /// Copy constructor. Both slices refer to the same underlying array. 73 indirect_array(const indirect_array&); 74 75 /// Assignment operator. Assigns elements to corresponding elements 76 /// of @a a. 77 indirect_array& operator=(const indirect_array&); 78 79 /// Assign slice elements to corresponding elements of @a v. 80 void operator=(const valarray<_Tp>&) const; 81 /// Multiply slice elements by corresponding elements of @a v. 82 void operator*=(const valarray<_Tp>&) const; 83 /// Divide slice elements by corresponding elements of @a v. 84 void operator/=(const valarray<_Tp>&) const; 85 /// Modulo slice elements by corresponding elements of @a v. 86 void operator%=(const valarray<_Tp>&) const; 87 /// Add corresponding elements of @a v to slice elements. 88 void operator+=(const valarray<_Tp>&) const; 89 /// Subtract corresponding elements of @a v from slice elements. 90 void operator-=(const valarray<_Tp>&) const; 91 /// Logical xor slice elements with corresponding elements of @a v. 92 void operator^=(const valarray<_Tp>&) const; 93 /// Logical and slice elements with corresponding elements of @a v. 94 void operator&=(const valarray<_Tp>&) const; 95 /// Logical or slice elements with corresponding elements of @a v. 96 void operator|=(const valarray<_Tp>&) const; 97 /// Left shift slice elements by corresponding elements of @a v. 98 void operator<<=(const valarray<_Tp>&) const; 99 /// Right shift slice elements by corresponding elements of @a v. 100 void operator>>=(const valarray<_Tp>&) const; 101 /// Assign all slice elements to @a t. 102 void operator= (const _Tp&) const; 103 // ~indirect_array(); 104 105 template<class _Dom> 106 void operator=(const _Expr<_Dom, _Tp>&) const; 107 template<class _Dom> 108 void operator*=(const _Expr<_Dom, _Tp>&) const; 109 template<class _Dom> 110 void operator/=(const _Expr<_Dom, _Tp>&) const; 111 template<class _Dom> 112 void operator%=(const _Expr<_Dom, _Tp>&) const; 113 template<class _Dom> 114 void operator+=(const _Expr<_Dom, _Tp>&) const; 115 template<class _Dom> 116 void operator-=(const _Expr<_Dom, _Tp>&) const; 117 template<class _Dom> 118 void operator^=(const _Expr<_Dom, _Tp>&) const; 119 template<class _Dom> 120 void operator&=(const _Expr<_Dom, _Tp>&) const; 121 template<class _Dom> 122 void operator|=(const _Expr<_Dom, _Tp>&) const; 123 template<class _Dom> 124 void operator<<=(const _Expr<_Dom, _Tp>&) const; 125 template<class _Dom> 126 void operator>>=(const _Expr<_Dom, _Tp>&) const; 127 128 private: 129 /// Copy constructor. Both slices refer to the same underlying array. 130 indirect_array(_Array<_Tp>, size_t, _Array<size_t>); 131 132 friend class valarray<_Tp>; 133 friend class gslice_array<_Tp>; 134 135 const size_t _M_sz; 136 const _Array<size_t> _M_index; 137 const _Array<_Tp> _M_array; 138 139 // not implemented 140 indirect_array(); 141 }; 142 143 template<typename _Tp> 144 inline 145 indirect_array<_Tp>::indirect_array(const indirect_array<_Tp>& __a) 146 : _M_sz(__a._M_sz), _M_index(__a._M_index), _M_array(__a._M_array) {} 147 148 template<typename _Tp> 149 inline 150 indirect_array<_Tp>::indirect_array(_Array<_Tp> __a, size_t __s, 151 _Array<size_t> __i) 152 : _M_sz(__s), _M_index(__i), _M_array(__a) {} 153 154 template<typename _Tp> 155 inline indirect_array<_Tp>& 156 indirect_array<_Tp>::operator=(const indirect_array<_Tp>& __a) 157 { 158 std::__valarray_copy(__a._M_array, _M_sz, __a._M_index, _M_array, 159 _M_index); 160 return *this; 161 } 162 163 template<typename _Tp> 164 inline void 165 indirect_array<_Tp>::operator=(const _Tp& __t) const 166 { std::__valarray_fill(_M_array, _M_index, _M_sz, __t); } 167 168 template<typename _Tp> 169 inline void 170 indirect_array<_Tp>::operator=(const valarray<_Tp>& __v) const 171 { std::__valarray_copy(_Array<_Tp>(__v), _M_sz, _M_array, _M_index); } 172 173 template<typename _Tp> 174 template<class _Dom> 175 inline void 176 indirect_array<_Tp>::operator=(const _Expr<_Dom, _Tp>& __e) const 177 { std::__valarray_copy(__e, _M_sz, _M_array, _M_index); } 178 179 /// @cond undocumented 180 #undef _DEFINE_VALARRAY_OPERATOR 181 #define _DEFINE_VALARRAY_OPERATOR(_Op, _Name) \ 182 template<typename _Tp> \ 183 inline void \ 184 indirect_array<_Tp>::operator _Op##=(const valarray<_Tp>& __v) const\ 185 { \ 186 _Array_augmented_##_Name(_M_array, _M_index, _Array<_Tp>(__v), _M_sz); \ 187 } \ 188 \ 189 template<typename _Tp> \ 190 template<class _Dom> \ 191 inline void \ 192 indirect_array<_Tp>::operator _Op##=(const _Expr<_Dom,_Tp>& __e) const\ 193 { \ 194 _Array_augmented_##_Name(_M_array, _M_index, __e, _M_sz); \ 195 } 196 197 _DEFINE_VALARRAY_OPERATOR(*, __multiplies) 198 _DEFINE_VALARRAY_OPERATOR(/, __divides) 199 _DEFINE_VALARRAY_OPERATOR(%, __modulus) 200 _DEFINE_VALARRAY_OPERATOR(+, __plus) 201 _DEFINE_VALARRAY_OPERATOR(-, __minus) 202 _DEFINE_VALARRAY_OPERATOR(^, __bitwise_xor) 203 _DEFINE_VALARRAY_OPERATOR(&, __bitwise_and) 204 _DEFINE_VALARRAY_OPERATOR(|, __bitwise_or) 205 _DEFINE_VALARRAY_OPERATOR(<<, __shift_left) 206 _DEFINE_VALARRAY_OPERATOR(>>, __shift_right) 207 208 #undef _DEFINE_VALARRAY_OPERATOR 209 /// @endcond 210 211 /// @} group numeric_arrays 212 213 _GLIBCXX_END_NAMESPACE_VERSION 214 } // namespace 215 216 #endif /* _INDIRECT_ARRAY_H */
