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The C and C++ Include Header Files
cat -n /usr/include/c++/15/bits/slice_array.h
1 // The template and inlines for the -*- C++ -*- slice_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/slice_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 _SLICE_ARRAY_H 33 #define _SLICE_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 Class defining one-dimensional subset of an array. 50 * 51 * The slice class represents a one-dimensional subset of an array, 52 * specified by three parameters: start offset, size, and stride. The 53 * start offset is the index of the first element of the array that is part 54 * of the subset. The size is the total number of elements in the subset. 55 * Stride is the distance between each successive array element to include 56 * in the subset. 57 * 58 * For example, with an array of size 10, and a slice with offset 1, size 3 59 * and stride 2, the subset consists of array elements 1, 3, and 5. 60 */ 61 class slice 62 { 63 public: 64 /// Construct an empty slice. 65 slice(); 66 67 /** 68 * @brief Construct a slice. 69 * 70 * @param __o Offset in array of first element. 71 * @param __d Number of elements in slice. 72 * @param __s Stride between array elements. 73 */ 74 slice(size_t __o, size_t __d, size_t __s); 75 76 /// Return array offset of first slice element. 77 size_t start() const; 78 /// Return size of slice. 79 size_t size() const; 80 /// Return array stride of slice. 81 size_t stride() const; 82 83 #if __cpp_impl_three_way_comparison >= 201907L 84 /// Equality comparison 85 friend bool operator==(const slice&, const slice&) = default; 86 #endif 87 88 private: 89 size_t _M_off; // offset 90 size_t _M_sz; // size 91 size_t _M_st; // stride unit 92 }; 93 94 // _GLIBCXX_RESOLVE_LIB_DEFECTS 95 // 543. valarray slice default constructor 96 inline 97 slice::slice() 98 : _M_off(0), _M_sz(0), _M_st(0) {} 99 100 inline 101 slice::slice(size_t __o, size_t __d, size_t __s) 102 : _M_off(__o), _M_sz(__d), _M_st(__s) {} 103 104 inline size_t 105 slice::start() const 106 { return _M_off; } 107 108 inline size_t 109 slice::size() const 110 { return _M_sz; } 111 112 inline size_t 113 slice::stride() const 114 { return _M_st; } 115 116 /** 117 * @brief Reference to one-dimensional subset of an array. 118 * 119 * A slice_array is a reference to the actual elements of an array 120 * specified by a slice. The way to get a slice_array is to call 121 * operator[](slice) on a valarray. The returned slice_array then permits 122 * carrying operations out on the referenced subset of elements in the 123 * original valarray. For example, operator+=(valarray) will add values 124 * to the subset of elements in the underlying valarray this slice_array 125 * refers to. 126 * 127 * @param Tp Element type. 128 */ 129 template<typename _Tp> 130 class slice_array 131 { 132 public: 133 typedef _Tp value_type; 134 135 // _GLIBCXX_RESOLVE_LIB_DEFECTS 136 // 253. valarray helper functions are almost entirely useless 137 138 /// Copy constructor. Both slices refer to the same underlying array. 139 slice_array(const slice_array&); 140 141 /// Assignment operator. Assigns slice elements to corresponding 142 /// elements of @a a. 143 slice_array& operator=(const slice_array&); 144 145 /// Assign slice elements to corresponding elements of @a v. 146 void operator=(const valarray<_Tp>&) const; 147 /// Multiply slice elements by corresponding elements of @a v. 148 void operator*=(const valarray<_Tp>&) const; 149 /// Divide slice elements by corresponding elements of @a v. 150 void operator/=(const valarray<_Tp>&) const; 151 /// Modulo slice elements by corresponding elements of @a v. 152 void operator%=(const valarray<_Tp>&) const; 153 /// Add corresponding elements of @a v to slice elements. 154 void operator+=(const valarray<_Tp>&) const; 155 /// Subtract corresponding elements of @a v from slice elements. 156 void operator-=(const valarray<_Tp>&) const; 157 /// Logical xor slice elements with corresponding elements of @a v. 158 void operator^=(const valarray<_Tp>&) const; 159 /// Logical and slice elements with corresponding elements of @a v. 160 void operator&=(const valarray<_Tp>&) const; 161 /// Logical or slice elements with corresponding elements of @a v. 162 void operator|=(const valarray<_Tp>&) const; 163 /// Left shift slice elements by corresponding elements of @a v. 164 void operator<<=(const valarray<_Tp>&) const; 165 /// Right shift slice elements by corresponding elements of @a v. 166 void operator>>=(const valarray<_Tp>&) const; 167 /// Assign all slice elements to @a t. 168 void operator=(const _Tp &) const; 169 // ~slice_array (); 170 171 template<class _Dom> 172 void operator=(const _Expr<_Dom, _Tp>&) const; 173 template<class _Dom> 174 void operator*=(const _Expr<_Dom, _Tp>&) const; 175 template<class _Dom> 176 void operator/=(const _Expr<_Dom, _Tp>&) const; 177 template<class _Dom> 178 void operator%=(const _Expr<_Dom, _Tp>&) const; 179 template<class _Dom> 180 void operator+=(const _Expr<_Dom, _Tp>&) const; 181 template<class _Dom> 182 void operator-=(const _Expr<_Dom, _Tp>&) const; 183 template<class _Dom> 184 void operator^=(const _Expr<_Dom, _Tp>&) const; 185 template<class _Dom> 186 void operator&=(const _Expr<_Dom, _Tp>&) const; 187 template<class _Dom> 188 void operator|=(const _Expr<_Dom, _Tp>&) const; 189 template<class _Dom> 190 void operator<<=(const _Expr<_Dom, _Tp>&) const; 191 template<class _Dom> 192 void operator>>=(const _Expr<_Dom, _Tp>&) const; 193 194 private: 195 friend class valarray<_Tp>; 196 slice_array(_Array<_Tp>, const slice&); 197 198 const size_t _M_sz; 199 const size_t _M_stride; 200 const _Array<_Tp> _M_array; 201 202 #if __cplusplus < 201103L 203 // not implemented 204 slice_array(); 205 #else 206 public: 207 slice_array() = delete; 208 #endif 209 }; 210 211 template<typename _Tp> 212 inline 213 slice_array<_Tp>::slice_array(_Array<_Tp> __a, const slice& __s) 214 : _M_sz(__s.size()), _M_stride(__s.stride()), 215 _M_array(__a.begin() + __s.start()) {} 216 217 template<typename _Tp> 218 inline 219 slice_array<_Tp>::slice_array(const slice_array<_Tp>& __a) 220 : _M_sz(__a._M_sz), _M_stride(__a._M_stride), _M_array(__a._M_array) {} 221 222 // template<typename _Tp> 223 // inline slice_array<_Tp>::~slice_array () {} 224 225 template<typename _Tp> 226 inline slice_array<_Tp>& 227 slice_array<_Tp>::operator=(const slice_array<_Tp>& __a) 228 { 229 std::__valarray_copy(__a._M_array, __a._M_sz, __a._M_stride, 230 _M_array, _M_stride); 231 return *this; 232 } 233 234 template<typename _Tp> 235 inline void 236 slice_array<_Tp>::operator=(const _Tp& __t) const 237 { std::__valarray_fill(_M_array, _M_sz, _M_stride, __t); } 238 239 template<typename _Tp> 240 inline void 241 slice_array<_Tp>::operator=(const valarray<_Tp>& __v) const 242 { std::__valarray_copy(_Array<_Tp>(__v), _M_array, _M_sz, _M_stride); } 243 244 template<typename _Tp> 245 template<class _Dom> 246 inline void 247 slice_array<_Tp>::operator=(const _Expr<_Dom,_Tp>& __e) const 248 { std::__valarray_copy(__e, _M_sz, _M_array, _M_stride); } 249 250 /// @cond undocumented 251 #undef _DEFINE_VALARRAY_OPERATOR 252 #define _DEFINE_VALARRAY_OPERATOR(_Op,_Name) \ 253 template<typename _Tp> \ 254 inline void \ 255 slice_array<_Tp>::operator _Op##=(const valarray<_Tp>& __v) const \ 256 { \ 257 _Array_augmented_##_Name(_M_array, _M_sz, _M_stride, _Array<_Tp>(__v));\ 258 } \ 259 \ 260 template<typename _Tp> \ 261 template<class _Dom> \ 262 inline void \ 263 slice_array<_Tp>::operator _Op##=(const _Expr<_Dom,_Tp>& __e) const\ 264 { \ 265 _Array_augmented_##_Name(_M_array, _M_stride, __e, _M_sz); \ 266 } 267 268 269 _DEFINE_VALARRAY_OPERATOR(*, __multiplies) 270 _DEFINE_VALARRAY_OPERATOR(/, __divides) 271 _DEFINE_VALARRAY_OPERATOR(%, __modulus) 272 _DEFINE_VALARRAY_OPERATOR(+, __plus) 273 _DEFINE_VALARRAY_OPERATOR(-, __minus) 274 _DEFINE_VALARRAY_OPERATOR(^, __bitwise_xor) 275 _DEFINE_VALARRAY_OPERATOR(&, __bitwise_and) 276 _DEFINE_VALARRAY_OPERATOR(|, __bitwise_or) 277 _DEFINE_VALARRAY_OPERATOR(<<, __shift_left) 278 _DEFINE_VALARRAY_OPERATOR(>>, __shift_right) 279 280 #undef _DEFINE_VALARRAY_OPERATOR 281 /// @endcond 282 283 /// @} group numeric_arrays 284 285 _GLIBCXX_END_NAMESPACE_VERSION 286 } // namespace 287 288 #endif /* _SLICE_ARRAY_H */
