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1 // Namespace std::regex_constants -*- C++ -*- 2 3 // Copyright (C) 2010-2025 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 /** 26 * @file bits/regex_constants.h 27 * @brief Constant definitions for the std regex library. 28 * 29 * This is an internal header file, included by other library headers. 30 * Do not attempt to use it directly. @headername{regex} 31 */ 32 33 namespace std _GLIBCXX_VISIBILITY(default) 34 { 35 _GLIBCXX_BEGIN_NAMESPACE_VERSION 36 37 /** 38 * @defgroup regex Regular Expressions 39 * 40 * A facility for performing regular expression pattern matching. 41 * 42 * @since C++11 43 * 44 * @{ 45 */ 46 47 /** 48 * @namespace std::regex_constants 49 * @brief ISO C++ 2011 namespace for options and flags used with std::regex 50 */ 51 namespace regex_constants 52 { 53 /** 54 * @name 5.1 Regular Expression Syntax Options 55 */ 56 ///@{ 57 58 /** 59 * @brief This is a bitmask type indicating how to interpret the regex. 60 * 61 * The @c syntax_option_type is implementation defined but it is valid to 62 * perform bitwise operations on these values and expect the right thing to 63 * happen. 64 * 65 * A valid value of type syntax_option_type shall have exactly one of the 66 * elements @c ECMAScript, @c basic, @c extended, @c awk, @c grep, @c egrep 67 * %set. 68 */ 69 enum [[__gnu__::__flag_enum__]] syntax_option_type : unsigned int 70 { 71 _S_icase = 1 << 0, 72 _S_nosubs = 1 << 1, 73 _S_optimize = 1 << 2, 74 _S_collate = 1 << 3, 75 _S_ECMAScript = 1 << 4, 76 _S_basic = 1 << 5, 77 _S_extended = 1 << 6, 78 _S_awk = 1 << 7, 79 _S_grep = 1 << 8, 80 _S_egrep = 1 << 9, 81 _S_polynomial = 1 << 10, 82 _S_multiline = 1 << 11 83 }; 84 85 /** 86 * Specifies that the matching of regular expressions against a character 87 * sequence shall be performed without regard to case. 88 */ 89 _GLIBCXX17_INLINE constexpr syntax_option_type icase = _S_icase; 90 91 /** 92 * Specifies that when a regular expression is matched against a character 93 * container sequence, no sub-expression matches are to be stored in the 94 * supplied match_results structure. 95 */ 96 _GLIBCXX17_INLINE constexpr syntax_option_type nosubs = _S_nosubs; 97 98 /** 99 * Specifies that the regular expression engine should pay more attention to 100 * the speed with which regular expressions are matched, and less to the 101 * speed with which regular expression objects are constructed. Otherwise 102 * it has no detectable effect on the program output. 103 */ 104 _GLIBCXX17_INLINE constexpr syntax_option_type optimize = _S_optimize; 105 106 /** 107 * Specifies that character ranges of the form [a-b] should be locale 108 * sensitive. 109 */ 110 _GLIBCXX17_INLINE constexpr syntax_option_type collate = _S_collate; 111 112 /** 113 * Specifies that the grammar recognized by the regular expression engine is 114 * that used by ECMAScript in ECMA-262 [Ecma International, ECMAScript 115 * Language Specification, Standard Ecma-262, third edition, 1999], as 116 * modified in section [28.13]. This grammar is similar to that defined 117 * in the PERL scripting language but extended with elements found in the 118 * POSIX regular expression grammar. 119 */ 120 _GLIBCXX17_INLINE constexpr syntax_option_type ECMAScript = _S_ECMAScript; 121 122 /** 123 * Specifies that the grammar recognized by the regular expression engine is 124 * that used by POSIX basic regular expressions in IEEE Std 1003.1-2001, 125 * Portable Operating System Interface (POSIX), Base Definitions and 126 * Headers, Section 9, Regular Expressions [IEEE, Information Technology -- 127 * Portable Operating System Interface (POSIX), IEEE Standard 1003.1-2001]. 128 */ 129 _GLIBCXX17_INLINE constexpr syntax_option_type basic = _S_basic; 130 131 /** 132 * Specifies that the grammar recognized by the regular expression engine is 133 * that used by POSIX extended regular expressions in IEEE Std 1003.1-2001, 134 * Portable Operating System Interface (POSIX), Base Definitions and 135 * Headers, Section 9, Regular Expressions. 136 */ 137 _GLIBCXX17_INLINE constexpr syntax_option_type extended = _S_extended; 138 139 /** 140 * Specifies that the grammar recognized by the regular expression engine is 141 * that used by POSIX utility awk in IEEE Std 1003.1-2001. This option is 142 * identical to syntax_option_type extended, except that C-style escape 143 * sequences are supported. These sequences are: 144 * \\\\, \\a, \\b, \\f, \\n, \\r, \\t , \\v, \\&apos,, &apos,, 145 * and \\ddd (where ddd is one, two, or three octal digits). 146 */ 147 _GLIBCXX17_INLINE constexpr syntax_option_type awk = _S_awk; 148 149 /** 150 * Specifies that the grammar recognized by the regular expression engine is 151 * that used by POSIX utility grep in IEEE Std 1003.1-2001. This option is 152 * identical to syntax_option_type basic, except that newlines are treated 153 * as whitespace. 154 */ 155 _GLIBCXX17_INLINE constexpr syntax_option_type grep = _S_grep; 156 157 /** 158 * Specifies that the grammar recognized by the regular expression engine is 159 * that used by POSIX utility grep when given the -E option in 160 * IEEE Std 1003.1-2001. This option is identical to syntax_option_type 161 * extended, except that newlines are treated as whitespace. 162 */ 163 _GLIBCXX17_INLINE constexpr syntax_option_type egrep = _S_egrep; 164 165 #if __cplusplus >= 201703L || !defined __STRICT_ANSI__ 166 // _GLIBCXX_RESOLVE_LIB_DEFECTS 167 // 2503. multiline option should be added to syntax_option_type 168 /** 169 * Specifies that the `^` anchor matches at the beginning of a line, 170 * and the `$` anchor matches at the end of a line, not only at the 171 * beginning/end of the input. 172 * Valid for the ECMAScript syntax, ignored otherwise. 173 * @since C++17 174 */ 175 _GLIBCXX17_INLINE constexpr syntax_option_type multiline = _S_multiline; 176 #endif 177 178 /// Extension: Equivalent to regex_constants::multiline for C++11 and C++14. 179 _GLIBCXX17_INLINE constexpr syntax_option_type __multiline = _S_multiline; 180 181 /** 182 * Extension: Ensure both space complexity of compiled regex and 183 * time complexity execution are not exponential. 184 * If specified in a regex with back-references, the exception 185 * regex_constants::error_complexity will be thrown. 186 */ 187 _GLIBCXX17_INLINE constexpr syntax_option_type __polynomial = _S_polynomial; 188 189 [[__nodiscard__]] 190 constexpr syntax_option_type 191 operator&(syntax_option_type __a, syntax_option_type __b) noexcept 192 { 193 return (syntax_option_type)(static_cast<unsigned int>(__a) 194 & static_cast<unsigned int>(__b)); 195 } 196 197 [[__nodiscard__]] 198 constexpr syntax_option_type 199 operator|(syntax_option_type __a, syntax_option_type __b) noexcept 200 { 201 return (syntax_option_type)(static_cast<unsigned int>(__a) 202 | static_cast<unsigned int>(__b)); 203 } 204 205 [[__nodiscard__]] 206 constexpr syntax_option_type 207 operator^(syntax_option_type __a, syntax_option_type __b) noexcept 208 { 209 return (syntax_option_type)(static_cast<unsigned int>(__a) 210 ^ static_cast<unsigned int>(__b)); 211 } 212 213 [[__nodiscard__]] 214 constexpr syntax_option_type 215 operator~(syntax_option_type __a) noexcept 216 { return (syntax_option_type)(~static_cast<unsigned int>(__a)); } 217 218 _GLIBCXX14_CONSTEXPR 219 inline syntax_option_type& 220 operator&=(syntax_option_type& __a, syntax_option_type __b) noexcept 221 { return __a = __a & __b; } 222 223 _GLIBCXX14_CONSTEXPR 224 inline syntax_option_type& 225 operator|=(syntax_option_type& __a, syntax_option_type __b) noexcept 226 { return __a = __a | __b; } 227 228 _GLIBCXX14_CONSTEXPR 229 inline syntax_option_type& 230 operator^=(syntax_option_type& __a, syntax_option_type __b) noexcept 231 { return __a = __a ^ __b; } 232 233 ///@} 234 235 /** 236 * @name 5.2 Matching Rules 237 * 238 * Matching a regular expression against a sequence of characters [first, 239 * last) proceeds according to the rules of the grammar specified for the 240 * regular expression object, modified according to the effects listed 241 * below for any bitmask elements set. 242 * 243 */ 244 ///@{ 245 246 /** 247 * @brief This is a bitmask type indicating regex matching rules. 248 * 249 * The @c match_flag_type is implementation defined but it is valid to 250 * perform bitwise operations on these values and expect the right thing to 251 * happen. 252 */ 253 enum match_flag_type : unsigned int 254 { 255 _S_default, 256 _S_not_bol = 1 << 0, 257 _S_not_eol = 1 << 1, 258 _S_not_bow = 1 << 2, 259 _S_not_eow = 1 << 3, 260 _S_any = 1 << 4, 261 _S_not_null = 1 << 5, 262 _S_continuous = 1 << 6, 263 _S_prev_avail = 1 << 7, 264 _S_sed = 1 << 8, 265 _S_no_copy = 1 << 9, 266 _S_first_only = 1 << 10, 267 _S_match_flag_last = 1 << 11 268 }; 269 270 /** 271 * The default matching rules. 272 */ 273 _GLIBCXX17_INLINE constexpr match_flag_type match_default = _S_default; 274 275 /** 276 * The first character in the sequence [first, last) is treated as though it 277 * is not at the beginning of a line, so the character (^) in the regular 278 * expression shall not match [first, first). 279 */ 280 _GLIBCXX17_INLINE constexpr match_flag_type match_not_bol = _S_not_bol; 281 282 /** 283 * The last character in the sequence [first, last) is treated as though it 284 * is not at the end of a line, so the character ($) in the regular 285 * expression shall not match [last, last). 286 */ 287 _GLIBCXX17_INLINE constexpr match_flag_type match_not_eol = _S_not_eol; 288 289 /** 290 * The expression \\b is not matched against the sub-sequence 291 * [first,first). 292 */ 293 _GLIBCXX17_INLINE constexpr match_flag_type match_not_bow = _S_not_bow; 294 295 /** 296 * The expression \\b should not be matched against the sub-sequence 297 * [last,last). 298 */ 299 _GLIBCXX17_INLINE constexpr match_flag_type match_not_eow = _S_not_eow; 300 301 /** 302 * If more than one match is possible then any match is an acceptable 303 * result. 304 */ 305 _GLIBCXX17_INLINE constexpr match_flag_type match_any = _S_any; 306 307 /** 308 * The expression does not match an empty sequence. 309 */ 310 _GLIBCXX17_INLINE constexpr match_flag_type match_not_null = _S_not_null; 311 312 /** 313 * The expression only matches a sub-sequence that begins at first . 314 */ 315 _GLIBCXX17_INLINE constexpr match_flag_type match_continuous = _S_continuous; 316 317 /** 318 * `--first` is a valid iterator position. When this flag is set then the 319 * flags `match_not_bol` and `match_not_bow` are ignored by the algorithms 320 * `regex_match`, `regex_search`, and `regex_replace`, and by the iterators 321 * `regex_iterator` and `regex_token_iterator`. 322 */ 323 _GLIBCXX17_INLINE constexpr match_flag_type match_prev_avail = _S_prev_avail; 324 325 /** 326 * When a regular expression match is to be replaced by a new string, the 327 * new string is constructed using the rules used by the ECMAScript replace 328 * function in ECMA- 262 [Ecma International, ECMAScript Language 329 * Specification, Standard Ecma-262, third edition, 1999], part 15.5.4.11 330 * String.prototype.replace. In addition, during search and replace 331 * operations all non-overlapping occurrences of the regular expression 332 * are located and replaced, and sections of the input that did not match 333 * the expression are copied unchanged to the output string. 334 * 335 * Format strings (from ECMA-262 [15.5.4.11]): 336 * @li $$ The dollar-sign itself ($) 337 * @li $& The matched substring. 338 * @li $` The portion of @a string that precedes the matched substring. 339 * This would be match_results::prefix(). 340 * @li $' The portion of @a string that follows the matched substring. 341 * This would be match_results::suffix(). 342 * @li $n The nth capture, where n is in [1,9] and $n is not followed by a 343 * decimal digit. If n <= match_results::size() and the nth capture 344 * is undefined, use the empty string instead. If n > 345 * match_results::size(), the result is implementation-defined. 346 * @li $nn The nnth capture, where nn is a two-digit decimal number on 347 * [01, 99]. If nn <= match_results::size() and the nth capture is 348 * undefined, use the empty string instead. If 349 * nn > match_results::size(), the result is implementation-defined. 350 */ 351 _GLIBCXX17_INLINE constexpr match_flag_type format_default = _S_default; 352 353 /** 354 * When a regular expression match is to be replaced by a new string, the 355 * new string is constructed using the rules used by the POSIX sed utility 356 * in IEEE Std 1003.1- 2001 [IEEE, Information Technology -- Portable 357 * Operating System Interface (POSIX), IEEE Standard 1003.1-2001]. 358 */ 359 _GLIBCXX17_INLINE constexpr match_flag_type format_sed = _S_sed; 360 361 /** 362 * During a search and replace operation, sections of the character 363 * container sequence being searched that do not match the regular 364 * expression shall not be copied to the output string. 365 */ 366 _GLIBCXX17_INLINE constexpr match_flag_type format_no_copy = _S_no_copy; 367 368 /** 369 * When specified during a search and replace operation, only the first 370 * occurrence of the regular expression shall be replaced. 371 */ 372 _GLIBCXX17_INLINE constexpr match_flag_type format_first_only = _S_first_only; 373 374 [[__nodiscard__]] 375 constexpr match_flag_type 376 operator&(match_flag_type __a, match_flag_type __b) noexcept 377 { 378 return (match_flag_type)(static_cast<unsigned int>(__a) 379 & static_cast<unsigned int>(__b)); 380 } 381 382 [[__nodiscard__]] 383 constexpr match_flag_type 384 operator|(match_flag_type __a, match_flag_type __b) noexcept 385 { 386 return (match_flag_type)(static_cast<unsigned int>(__a) 387 | static_cast<unsigned int>(__b)); 388 } 389 390 [[__nodiscard__]] 391 constexpr match_flag_type 392 operator^(match_flag_type __a, match_flag_type __b) noexcept 393 { 394 return (match_flag_type)(static_cast<unsigned int>(__a) 395 ^ static_cast<unsigned int>(__b)); 396 } 397 398 [[__nodiscard__]] 399 constexpr match_flag_type 400 operator~(match_flag_type __a) noexcept 401 { return (match_flag_type)(~static_cast<unsigned int>(__a)); } 402 403 _GLIBCXX14_CONSTEXPR 404 inline match_flag_type& 405 operator&=(match_flag_type& __a, match_flag_type __b) noexcept 406 { return __a = __a & __b; } 407 408 _GLIBCXX14_CONSTEXPR 409 inline match_flag_type& 410 operator|=(match_flag_type& __a, match_flag_type __b) noexcept 411 { return __a = __a | __b; } 412 413 _GLIBCXX14_CONSTEXPR 414 inline match_flag_type& 415 operator^=(match_flag_type& __a, match_flag_type __b) noexcept 416 { return __a = __a ^ __b; } 417 418 ///@} 419 } // namespace regex_constants 420 /// @} group regex 421 422 _GLIBCXX_END_NAMESPACE_VERSION 423 } // namespace std 424
