libstdc++
regex_constants.h
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1 // class template regex -*- C++ -*-
2 
3 // Copyright (C) 2010-2021 Free Software Foundation, Inc.
4 //
5 // This file is part of the GNU ISO C++ Library. This library is free
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7 // terms of the GNU General Public License as published by the
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9 // any later version.
10 
11 // This library is distributed in the hope that it will be useful,
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15 
16 // Under Section 7 of GPL version 3, you are granted additional
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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
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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  */
43 
44 /**
45  * @namespace std::regex_constants
46  * @brief ISO C++ 2011 namespace for options and flags used with std::regex
47  */
48 namespace regex_constants
49 {
50  /**
51  * @name 5.1 Regular Expression Syntax Options
52  */
53  ///@{
55  {
56  _S_icase,
57  _S_nosubs,
58  _S_optimize,
59  _S_collate,
60  _S_ECMAScript,
61  _S_basic,
62  _S_extended,
63  _S_awk,
64  _S_grep,
65  _S_egrep,
66  _S_polynomial,
67  _S_syntax_last
68  };
69 
70  /**
71  * @brief This is a bitmask type indicating how to interpret the regex.
72  *
73  * The @c syntax_option_type is implementation defined but it is valid to
74  * perform bitwise operations on these values and expect the right thing to
75  * happen.
76  *
77  * A valid value of type syntax_option_type shall have exactly one of the
78  * elements @c ECMAScript, @c basic, @c extended, @c awk, @c grep, @c egrep
79  * %set.
80  */
81  enum syntax_option_type : unsigned int { };
82 
83  /**
84  * Specifies that the matching of regular expressions against a character
85  * sequence shall be performed without regard to case.
86  */
87  _GLIBCXX17_INLINE constexpr syntax_option_type icase =
88  static_cast<syntax_option_type>(1 << _S_icase);
89 
90  /**
91  * Specifies that when a regular expression is matched against a character
92  * container sequence, no sub-expression matches are to be stored in the
93  * supplied match_results structure.
94  */
95  _GLIBCXX17_INLINE constexpr syntax_option_type nosubs =
96  static_cast<syntax_option_type>(1 << _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 =
105  static_cast<syntax_option_type>(1 << _S_optimize);
106 
107  /**
108  * Specifies that character ranges of the form [a-b] should be locale
109  * sensitive.
110  */
111  _GLIBCXX17_INLINE constexpr syntax_option_type collate =
112  static_cast<syntax_option_type>(1 << _S_collate);
113 
114  /**
115  * Specifies that the grammar recognized by the regular expression engine is
116  * that used by ECMAScript in ECMA-262 [Ecma International, ECMAScript
117  * Language Specification, Standard Ecma-262, third edition, 1999], as
118  * modified in section [28.13]. This grammar is similar to that defined
119  * in the PERL scripting language but extended with elements found in the
120  * POSIX regular expression grammar.
121  */
122  _GLIBCXX17_INLINE constexpr syntax_option_type ECMAScript =
123  static_cast<syntax_option_type>(1 << _S_ECMAScript);
124 
125  /**
126  * Specifies that the grammar recognized by the regular expression engine is
127  * that used by POSIX basic regular expressions in IEEE Std 1003.1-2001,
128  * Portable Operating System Interface (POSIX), Base Definitions and
129  * Headers, Section 9, Regular Expressions [IEEE, Information Technology --
130  * Portable Operating System Interface (POSIX), IEEE Standard 1003.1-2001].
131  */
132  _GLIBCXX17_INLINE constexpr syntax_option_type basic =
133  static_cast<syntax_option_type>(1 << _S_basic);
134 
135  /**
136  * Specifies that the grammar recognized by the regular expression engine is
137  * that used by POSIX extended regular expressions in IEEE Std 1003.1-2001,
138  * Portable Operating System Interface (POSIX), Base Definitions and
139  * Headers, Section 9, Regular Expressions.
140  */
141  _GLIBCXX17_INLINE constexpr syntax_option_type extended =
142  static_cast<syntax_option_type>(1 << _S_extended);
143 
144  /**
145  * Specifies that the grammar recognized by the regular expression engine is
146  * that used by POSIX utility awk in IEEE Std 1003.1-2001. This option is
147  * identical to syntax_option_type extended, except that C-style escape
148  * sequences are supported. These sequences are:
149  * \\\\, \\a, \\b, \\f, \\n, \\r, \\t , \\v, \\&apos,, &apos,,
150  * and \\ddd (where ddd is one, two, or three octal digits).
151  */
152  _GLIBCXX17_INLINE constexpr syntax_option_type awk =
153  static_cast<syntax_option_type>(1 << _S_awk);
154 
155  /**
156  * Specifies that the grammar recognized by the regular expression engine is
157  * that used by POSIX utility grep in IEEE Std 1003.1-2001. This option is
158  * identical to syntax_option_type basic, except that newlines are treated
159  * as whitespace.
160  */
161  _GLIBCXX17_INLINE constexpr syntax_option_type grep =
162  static_cast<syntax_option_type>(1 << _S_grep);
163 
164  /**
165  * Specifies that the grammar recognized by the regular expression engine is
166  * that used by POSIX utility grep when given the -E option in
167  * IEEE Std 1003.1-2001. This option is identical to syntax_option_type
168  * extended, except that newlines are treated as whitespace.
169  */
170  _GLIBCXX17_INLINE constexpr syntax_option_type egrep =
171  static_cast<syntax_option_type>(1 << _S_egrep);
172 
173  /**
174  * Extension: Ensure both space complexity of compiled regex and
175  * time complexity execution are not exponential.
176  * If specified in a regex with back-references, the exception
177  * regex_constants::error_complexity will be thrown.
178  */
179  _GLIBCXX17_INLINE constexpr syntax_option_type __polynomial =
180  static_cast<syntax_option_type>(1 << _S_polynomial);
181 
182  constexpr inline syntax_option_type
184  {
185  return (syntax_option_type)(static_cast<unsigned int>(__a)
186  & static_cast<unsigned int>(__b));
187  }
188 
189  constexpr inline syntax_option_type
191  {
192  return (syntax_option_type)(static_cast<unsigned int>(__a)
193  | static_cast<unsigned int>(__b));
194  }
195 
196  constexpr inline syntax_option_type
198  {
199  return (syntax_option_type)(static_cast<unsigned int>(__a)
200  ^ static_cast<unsigned int>(__b));
201  }
202 
203  constexpr inline syntax_option_type
205  { return (syntax_option_type)(~static_cast<unsigned int>(__a)); }
206 
207  inline syntax_option_type&
209  { return __a = __a & __b; }
210 
211  inline syntax_option_type&
213  { return __a = __a | __b; }
214 
215  inline syntax_option_type&
217  { return __a = __a ^ __b; }
218 
219  ///@}
220 
221  /**
222  * @name 5.2 Matching Rules
223  *
224  * Matching a regular expression against a sequence of characters [first,
225  * last) proceeds according to the rules of the grammar specified for the
226  * regular expression object, modified according to the effects listed
227  * below for any bitmask elements set.
228  *
229  */
230  ///@{
231 
233  {
234  _S_not_bol,
235  _S_not_eol,
236  _S_not_bow,
237  _S_not_eow,
238  _S_any,
239  _S_not_null,
240  _S_continuous,
241  _S_prev_avail,
242  _S_sed,
243  _S_no_copy,
244  _S_first_only,
245  _S_match_flag_last
246  };
247 
248  /**
249  * @brief This is a bitmask type indicating regex matching rules.
250  *
251  * The @c match_flag_type is implementation defined but it is valid to
252  * perform bitwise operations on these values and expect the right thing to
253  * happen.
254  */
255  enum match_flag_type : unsigned int { };
256 
257  /**
258  * The default matching rules.
259  */
260  _GLIBCXX17_INLINE constexpr match_flag_type match_default =
261  static_cast<match_flag_type>(0);
262 
263  /**
264  * The first character in the sequence [first, last) is treated as though it
265  * is not at the beginning of a line, so the character (^) in the regular
266  * expression shall not match [first, first).
267  */
268  _GLIBCXX17_INLINE constexpr match_flag_type match_not_bol =
269  static_cast<match_flag_type>(1 << _S_not_bol);
270 
271  /**
272  * The last character in the sequence [first, last) is treated as though it
273  * is not at the end of a line, so the character ($) in the regular
274  * expression shall not match [last, last).
275  */
276  _GLIBCXX17_INLINE constexpr match_flag_type match_not_eol =
277  static_cast<match_flag_type>(1 << _S_not_eol);
278 
279  /**
280  * The expression \\b is not matched against the sub-sequence
281  * [first,first).
282  */
283  _GLIBCXX17_INLINE constexpr match_flag_type match_not_bow =
284  static_cast<match_flag_type>(1 << _S_not_bow);
285 
286  /**
287  * The expression \\b should not be matched against the sub-sequence
288  * [last,last).
289  */
290  _GLIBCXX17_INLINE constexpr match_flag_type match_not_eow =
291  static_cast<match_flag_type>(1 << _S_not_eow);
292 
293  /**
294  * If more than one match is possible then any match is an acceptable
295  * result.
296  */
297  _GLIBCXX17_INLINE constexpr match_flag_type match_any =
298  static_cast<match_flag_type>(1 << _S_any);
299 
300  /**
301  * The expression does not match an empty sequence.
302  */
303  _GLIBCXX17_INLINE constexpr match_flag_type match_not_null =
304  static_cast<match_flag_type>(1 << _S_not_null);
305 
306  /**
307  * The expression only matches a sub-sequence that begins at first .
308  */
309  _GLIBCXX17_INLINE constexpr match_flag_type match_continuous =
310  static_cast<match_flag_type>(1 << _S_continuous);
311 
312  /**
313  * --first is a valid iterator position. When this flag is set then the
314  * flags match_not_bol and match_not_bow are ignored by the regular
315  * expression algorithms 28.11 and iterators 28.12.
316  */
317  _GLIBCXX17_INLINE constexpr match_flag_type match_prev_avail =
318  static_cast<match_flag_type>(1 << _S_prev_avail);
319 
320  /**
321  * When a regular expression match is to be replaced by a new string, the
322  * new string is constructed using the rules used by the ECMAScript replace
323  * function in ECMA- 262 [Ecma International, ECMAScript Language
324  * Specification, Standard Ecma-262, third edition, 1999], part 15.5.4.11
325  * String.prototype.replace. In addition, during search and replace
326  * operations all non-overlapping occurrences of the regular expression
327  * are located and replaced, and sections of the input that did not match
328  * the expression are copied unchanged to the output string.
329  *
330  * Format strings (from ECMA-262 [15.5.4.11]):
331  * @li $$ The dollar-sign itself ($)
332  * @li $& The matched substring.
333  * @li $` The portion of @a string that precedes the matched substring.
334  * This would be match_results::prefix().
335  * @li $' The portion of @a string that follows the matched substring.
336  * This would be match_results::suffix().
337  * @li $n The nth capture, where n is in [1,9] and $n is not followed by a
338  * decimal digit. If n <= match_results::size() and the nth capture
339  * is undefined, use the empty string instead. If n >
340  * match_results::size(), the result is implementation-defined.
341  * @li $nn The nnth capture, where nn is a two-digit decimal number on
342  * [01, 99]. If nn <= match_results::size() and the nth capture is
343  * undefined, use the empty string instead. If
344  * nn > match_results::size(), the result is implementation-defined.
345  */
346  _GLIBCXX17_INLINE constexpr match_flag_type format_default =
347  static_cast<match_flag_type>(0);
348 
349  /**
350  * When a regular expression match is to be replaced by a new string, the
351  * new string is constructed using the rules used by the POSIX sed utility
352  * in IEEE Std 1003.1- 2001 [IEEE, Information Technology -- Portable
353  * Operating System Interface (POSIX), IEEE Standard 1003.1-2001].
354  */
355  _GLIBCXX17_INLINE constexpr match_flag_type format_sed =
356  static_cast<match_flag_type>(1 << _S_sed);
357 
358  /**
359  * During a search and replace operation, sections of the character
360  * container sequence being searched that do not match the regular
361  * expression shall not be copied to the output string.
362  */
363  _GLIBCXX17_INLINE constexpr match_flag_type format_no_copy =
364  static_cast<match_flag_type>(1 << _S_no_copy);
365 
366  /**
367  * When specified during a search and replace operation, only the first
368  * occurrence of the regular expression shall be replaced.
369  */
370  _GLIBCXX17_INLINE constexpr match_flag_type format_first_only =
371  static_cast<match_flag_type>(1 << _S_first_only);
372 
373  constexpr inline match_flag_type
375  {
376  return (match_flag_type)(static_cast<unsigned int>(__a)
377  & static_cast<unsigned int>(__b));
378  }
379 
380  constexpr inline match_flag_type
382  {
383  return (match_flag_type)(static_cast<unsigned int>(__a)
384  | static_cast<unsigned int>(__b));
385  }
386 
387  constexpr inline match_flag_type
389  {
390  return (match_flag_type)(static_cast<unsigned int>(__a)
391  ^ static_cast<unsigned int>(__b));
392  }
393 
394  constexpr inline match_flag_type
396  { return (match_flag_type)(~static_cast<unsigned int>(__a)); }
397 
398  inline match_flag_type&
400  { return __a = __a & __b; }
401 
402  inline match_flag_type&
404  { return __a = __a | __b; }
405 
406  inline match_flag_type&
408  { return __a = __a ^ __b; }
409 
410  ///@}
411 } // namespace regex_constants
412 /// @} group regex
413 
414 _GLIBCXX_END_NAMESPACE_VERSION
415 } // namespace std
416 
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)
This is a bitmask type indicating how to interpret the regex.
__match_flag
This is a bitmask type indicating regex matching rules.
constexpr match_flag_type match_not_bow
constexpr match_flag_type match_not_bol
constexpr syntax_option_type ECMAScript
constexpr match_flag_type match_any
constexpr syntax_option_type egrep
syntax_option_type & operator|=(syntax_option_type &__a, syntax_option_type __b)
This is a bitmask type indicating how to interpret the regex.
syntax_option_type
This is a bitmask type indicating how to interpret the regex.
__syntax_option
This is a bitmask type indicating how to interpret the regex.
syntax_option_type & operator^=(syntax_option_type &__a, syntax_option_type __b)
This is a bitmask type indicating how to interpret the regex.
constexpr match_flag_type match_default
constexpr match_flag_type format_first_only
constexpr syntax_option_type awk
constexpr match_flag_type match_continuous
constexpr syntax_option_type extended
constexpr syntax_option_type operator^(syntax_option_type __a, syntax_option_type __b)
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 optimize
constexpr match_flag_type format_default
constexpr syntax_option_type nosubs
syntax_option_type & operator&=(syntax_option_type &__a, syntax_option_type __b)
This is a bitmask type indicating how to interpret the regex.
constexpr syntax_option_type operator~(syntax_option_type __a)
This is a bitmask type indicating how to interpret the regex.
constexpr match_flag_type match_prev_avail
constexpr match_flag_type format_sed
constexpr syntax_option_type operator|(syntax_option_type __a, syntax_option_type __b)
This is a bitmask type indicating how to interpret the regex.
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.