libstdc++
regex_constants.h
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1 // class template regex -*- C++ -*-
2 
3 // Copyright (C) 2010, 2011 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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10 
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13 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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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 
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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 /**
36  * @namespace std::regex_constants
37  * @brief ISO C++-0x entities sub namespace for regex.
38  */
39 namespace regex_constants
40 {
41 _GLIBCXX_BEGIN_NAMESPACE_VERSION
42 
43  /**
44  * @name 5.1 Regular Expression Syntax Options
45  */
46  //@{
48  {
49  _S_icase,
50  _S_nosubs,
51  _S_optimize,
52  _S_collate,
53  _S_ECMAScript,
54  _S_basic,
55  _S_extended,
56  _S_awk,
57  _S_grep,
58  _S_egrep,
59  _S_syntax_last
60  };
61 
62  /**
63  * @brief This is a bitmask type indicating how to interpret the regex.
64  *
65  * The @c syntax_option_type is implementation defined but it is valid to
66  * perform bitwise operations on these values and expect the right thing to
67  * happen.
68  *
69  * A valid value of type syntax_option_type shall have exactly one of the
70  * elements @c ECMAScript, @c basic, @c extended, @c awk, @c grep, @c egrep
71  * %set.
72  */
73  typedef unsigned int syntax_option_type;
74 
75  /**
76  * Specifies that the matching of regular expressions against a character
77  * sequence shall be performed without regard to case.
78  */
79  static constexpr syntax_option_type icase = 1 << _S_icase;
80 
81  /**
82  * Specifies that when a regular expression is matched against a character
83  * container sequence, no sub-expression matches are to be stored in the
84  * supplied match_results structure.
85  */
86  static constexpr syntax_option_type nosubs = 1 << _S_nosubs;
87 
88  /**
89  * Specifies that the regular expression engine should pay more attention to
90  * the speed with which regular expressions are matched, and less to the
91  * speed with which regular expression objects are constructed. Otherwise
92  * it has no detectable effect on the program output.
93  */
94  static constexpr syntax_option_type optimize = 1 << _S_optimize;
95 
96  /**
97  * Specifies that character ranges of the form [a-b] should be locale
98  * sensitive.
99  */
100  static constexpr syntax_option_type collate = 1 << _S_collate;
101 
102  /**
103  * Specifies that the grammar recognized by the regular expression engine is
104  * that used by ECMAScript in ECMA-262 [Ecma International, ECMAScript
105  * Language Specification, Standard Ecma-262, third edition, 1999], as
106  * modified in section [28.13]. This grammar is similar to that defined
107  * in the PERL scripting language but extended with elements found in the
108  * POSIX regular expression grammar.
109  */
110  static constexpr syntax_option_type ECMAScript = 1 << _S_ECMAScript;
111 
112  /**
113  * Specifies that the grammar recognized by the regular expression engine is
114  * that used by POSIX basic regular expressions in IEEE Std 1003.1-2001,
115  * Portable Operating System Interface (POSIX), Base Definitions and
116  * Headers, Section 9, Regular Expressions [IEEE, Information Technology --
117  * Portable Operating System Interface (POSIX), IEEE Standard 1003.1-2001].
118  */
119  static constexpr syntax_option_type basic = 1 << _S_basic;
120 
121  /**
122  * Specifies that the grammar recognized by the regular expression engine is
123  * that used by POSIX extended regular expressions in IEEE Std 1003.1-2001,
124  * Portable Operating System Interface (POSIX), Base Definitions and Headers,
125  * Section 9, Regular Expressions.
126  */
127  static constexpr syntax_option_type extended = 1 << _S_extended;
128 
129  /**
130  * Specifies that the grammar recognized by the regular expression engine is
131  * that used by POSIX utility awk in IEEE Std 1003.1-2001. This option is
132  * identical to syntax_option_type extended, except that C-style escape
133  * sequences are supported. These sequences are:
134  * \\\\, \\a, \\b, \\f, \\n, \\r, \\t , \\v, \\&apos;, &apos;,
135  * and \\ddd (where ddd is one, two, or three octal digits).
136  */
137  static constexpr syntax_option_type awk = 1 << _S_awk;
138 
139  /**
140  * Specifies that the grammar recognized by the regular expression engine is
141  * that used by POSIX utility grep in IEEE Std 1003.1-2001. This option is
142  * identical to syntax_option_type basic, except that newlines are treated
143  * as whitespace.
144  */
145  static constexpr syntax_option_type grep = 1 << _S_grep;
146 
147  /**
148  * Specifies that the grammar recognized by the regular expression engine is
149  * that used by POSIX utility grep when given the -E option in
150  * IEEE Std 1003.1-2001. This option is identical to syntax_option_type
151  * extended, except that newlines are treated as whitespace.
152  */
153  static constexpr syntax_option_type egrep = 1 << _S_egrep;
154 
155  //@}
156 
157  /**
158  * @name 5.2 Matching Rules
159  *
160  * Matching a regular expression against a sequence of characters [first,
161  * last) proceeds according to the rules of the grammar specified for the
162  * regular expression object, modified according to the effects listed
163  * below for any bitmask elements set.
164  *
165  */
166  //@{
167 
169  {
170  _S_not_bol,
171  _S_not_eol,
172  _S_not_bow,
173  _S_not_eow,
174  _S_any,
175  _S_not_null,
176  _S_continuous,
177  _S_prev_avail,
178  _S_sed,
179  _S_no_copy,
180  _S_first_only,
181  _S_match_flag_last
182  };
183 
184  /**
185  * @brief This is a bitmask type indicating regex matching rules.
186  *
187  * The @c match_flag_type is implementation defined but it is valid to
188  * perform bitwise operations on these values and expect the right thing to
189  * happen.
190  */
191  typedef std::bitset<_S_match_flag_last> match_flag_type;
192 
193  /**
194  * The default matching rules.
195  */
196  static constexpr match_flag_type match_default = 0;
197 
198  /**
199  * The first character in the sequence [first, last) is treated as though it
200  * is not at the beginning of a line, so the character (^) in the regular
201  * expression shall not match [first, first).
202  */
203  static constexpr match_flag_type match_not_bol = 1 << _S_not_bol;
204 
205  /**
206  * The last character in the sequence [first, last) is treated as though it
207  * is not at the end of a line, so the character ($) in the regular
208  * expression shall not match [last, last).
209  */
210  static constexpr match_flag_type match_not_eol = 1 << _S_not_eol;
211 
212  /**
213  * The expression \\b is not matched against the sub-sequence
214  * [first,first).
215  */
216  static constexpr match_flag_type match_not_bow = 1 << _S_not_bow;
217 
218  /**
219  * The expression \\b should not be matched against the sub-sequence
220  * [last,last).
221  */
222  static constexpr match_flag_type match_not_eow = 1 << _S_not_eow;
223 
224  /**
225  * If more than one match is possible then any match is an acceptable
226  * result.
227  */
228  static constexpr match_flag_type match_any = 1 << _S_any;
229 
230  /**
231  * The expression does not match an empty sequence.
232  */
233  static constexpr match_flag_type match_not_null = 1 << _S_not_null;
234 
235  /**
236  * The expression only matches a sub-sequence that begins at first .
237  */
238  static constexpr match_flag_type match_continuous = 1 << _S_continuous;
239 
240  /**
241  * --first is a valid iterator position. When this flag is set then the
242  * flags match_not_bol and match_not_bow are ignored by the regular
243  * expression algorithms 28.11 and iterators 28.12.
244  */
245  static constexpr match_flag_type match_prev_avail = 1 << _S_prev_avail;
246 
247  /**
248  * When a regular expression match is to be replaced by a new string, the
249  * new string is constructed using the rules used by the ECMAScript replace
250  * function in ECMA- 262 [Ecma International, ECMAScript Language
251  * Specification, Standard Ecma-262, third edition, 1999], part 15.5.4.11
252  * String.prototype.replace. In addition, during search and replace
253  * operations all non-overlapping occurrences of the regular expression
254  * are located and replaced, and sections of the input that did not match
255  * the expression are copied unchanged to the output string.
256  *
257  * Format strings (from ECMA-262 [15.5.4.11]):
258  * @li $$ The dollar-sign itself ($)
259  * @li $& The matched substring.
260  * @li $` The portion of @a string that precedes the matched substring.
261  * This would be match_results::prefix().
262  * @li $' The portion of @a string that follows the matched substring.
263  * This would be match_results::suffix().
264  * @li $n The nth capture, where n is in [1,9] and $n is not followed by a
265  * decimal digit. If n <= match_results::size() and the nth capture
266  * is undefined, use the empty string instead. If n >
267  * match_results::size(), the result is implementation-defined.
268  * @li $nn The nnth capture, where nn is a two-digit decimal number on
269  * [01, 99]. If nn <= match_results::size() and the nth capture is
270  * undefined, use the empty string instead. If
271  * nn > match_results::size(), the result is implementation-defined.
272  */
273  static constexpr match_flag_type format_default = 0;
274 
275  /**
276  * When a regular expression match is to be replaced by a new string, the
277  * new string is constructed using the rules used by the POSIX sed utility
278  * in IEEE Std 1003.1- 2001 [IEEE, Information Technology -- Portable
279  * Operating System Interface (POSIX), IEEE Standard 1003.1-2001].
280  */
281  static constexpr match_flag_type format_sed = 1 << _S_sed;
282 
283  /**
284  * During a search and replace operation, sections of the character
285  * container sequence being searched that do not match the regular
286  * expression shall not be copied to the output string.
287  */
288  static constexpr match_flag_type format_no_copy = 1 << _S_no_copy;
289 
290  /**
291  * When specified during a search and replace operation, only the first
292  * occurrence of the regular expression shall be replaced.
293  */
294  static constexpr match_flag_type format_first_only = 1 << _S_first_only;
295 
296  //@}
297 
298 _GLIBCXX_END_NAMESPACE_VERSION
299 } // namespace regex_constants
300 } // namespace
301 
static constexpr syntax_option_type ECMAScript
Facet for localized string comparison.
static constexpr match_flag_type match_not_eol
static constexpr syntax_option_type icase
static constexpr match_flag_type match_prev_avail
static constexpr syntax_option_type nosubs
static constexpr match_flag_type format_sed
__match_flag
This is a bitmask type indicating regex matching rules.
static constexpr match_flag_type match_default
static constexpr match_flag_type match_not_bow
static constexpr match_flag_type match_any
std::bitset< _S_match_flag_last > match_flag_type
This is a bitmask type indicating regex matching rules.
static constexpr match_flag_type match_continuous
static constexpr syntax_option_type egrep
static constexpr match_flag_type match_not_bol
static constexpr match_flag_type format_first_only
static constexpr syntax_option_type basic
static constexpr match_flag_type match_not_null
static constexpr syntax_option_type awk
unsigned int syntax_option_type
This is a bitmask type indicating how to interpret the regex.
static constexpr syntax_option_type grep
static constexpr match_flag_type format_default
static constexpr syntax_option_type optimize
static constexpr match_flag_type format_no_copy
static constexpr match_flag_type match_not_eow
static constexpr syntax_option_type extended
__syntax_option
This is a bitmask type indicating how to interpret the regex.