libstdc++
regex_constants.h
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1 // Namespace std::regex_constants -*- C++ -*-
2 
3 // Copyright (C) 2010-2024 Free Software Foundation, Inc.
4 //
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15 
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19 
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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 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
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
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
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
216  { return (syntax_option_type)(~static_cast<unsigned int>(__a)); }
217 
218  _GLIBCXX14_CONSTEXPR
219  inline syntax_option_type&
221  { return __a = __a & __b; }
222 
223  _GLIBCXX14_CONSTEXPR
224  inline syntax_option_type&
226  { return __a = __a | __b; }
227 
228  _GLIBCXX14_CONSTEXPR
229  inline syntax_option_type&
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
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
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
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
401  { return (match_flag_type)(~static_cast<unsigned int>(__a)); }
402 
403  _GLIBCXX14_CONSTEXPR
404  inline match_flag_type&
406  { return __a = __a & __b; }
407 
408  _GLIBCXX14_CONSTEXPR
409  inline match_flag_type&
411  { return __a = __a | __b; }
412 
413  _GLIBCXX14_CONSTEXPR
414  inline match_flag_type&
416  { return __a = __a ^ __b; }
417 
418  ///@}
419 } // namespace regex_constants
420 /// @} group regex
421 
422 _GLIBCXX_END_NAMESPACE_VERSION
423 } // namespace std
424 
ISO C++ entities toplevel namespace is std.
constexpr syntax_option_type __polynomial
constexpr syntax_option_type & operator|=(syntax_option_type &__a, syntax_option_type __b) noexcept
This is a bitmask type indicating how to interpret the regex.
constexpr match_flag_type match_not_bow
constexpr match_flag_type match_not_bol
constexpr syntax_option_type ECMAScript
constexpr syntax_option_type & operator^=(syntax_option_type &__a, syntax_option_type __b) noexcept
This is a bitmask type indicating how to interpret the regex.
constexpr match_flag_type match_any
constexpr syntax_option_type egrep
syntax_option_type
This is a bitmask type indicating how to interpret the regex.
constexpr syntax_option_type operator&(syntax_option_type __a, syntax_option_type __b) noexcept
This is a bitmask type indicating how to interpret the regex.
constexpr syntax_option_type & operator&=(syntax_option_type &__a, syntax_option_type __b) noexcept
This is a bitmask type indicating how to interpret the regex.
constexpr syntax_option_type multiline
constexpr match_flag_type match_default
constexpr match_flag_type format_first_only
constexpr syntax_option_type awk
constexpr syntax_option_type __multiline
Extension: Equivalent to regex_constants::multiline for C++11 and C++14.
constexpr match_flag_type match_continuous
constexpr syntax_option_type extended
constexpr syntax_option_type operator|(syntax_option_type __a, syntax_option_type __b) noexcept
This is a bitmask type indicating how to interpret the regex.
constexpr syntax_option_type operator^(syntax_option_type __a, syntax_option_type __b) noexcept
This is a bitmask type indicating how to interpret the regex.
constexpr syntax_option_type basic
constexpr match_flag_type match_not_eol
match_flag_type
This is a bitmask type indicating regex matching rules.
constexpr syntax_option_type icase
constexpr syntax_option_type operator~(syntax_option_type __a) noexcept
This is a bitmask type indicating how to interpret the regex.
constexpr syntax_option_type optimize
constexpr match_flag_type format_default
constexpr syntax_option_type nosubs
constexpr match_flag_type match_prev_avail
constexpr match_flag_type format_sed
constexpr match_flag_type match_not_eow
constexpr match_flag_type match_not_null
constexpr match_flag_type format_no_copy
constexpr syntax_option_type grep
Facet for localized string comparison.