libstdc++
regex_constants.h
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00001 // class template regex -*- C++ -*-
00002 
00003 // Copyright (C) 2010-2013 Free Software Foundation, Inc.
00004 //
00005 // This file is part of the GNU ISO C++ Library.  This library is free
00006 // software; you can redistribute it and/or modify it under the
00007 // terms of the GNU General Public License as published by the
00008 // Free Software Foundation; either version 3, or (at your option)
00009 // any later version.
00010 
00011 // This library is distributed in the hope that it will be useful,
00012 // but WITHOUT ANY WARRANTY; without even the implied warranty of
00013 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
00014 // GNU General Public License for more details.
00015 
00016 // Under Section 7 of GPL version 3, you are granted additional
00017 // permissions described in the GCC Runtime Library Exception, version
00018 // 3.1, as published by the Free Software Foundation.
00019 
00020 // You should have received a copy of the GNU General Public License and
00021 // a copy of the GCC Runtime Library Exception along with this program;
00022 // see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
00023 // <http://www.gnu.org/licenses/>.
00024 
00025 /**
00026  *  @file bits/regex_constants.h
00027  *  @brief Constant definitions for the std regex library.
00028  *
00029  *  This is an internal header file, included by other library headers.
00030  *  Do not attempt to use it directly. @headername{regex}
00031  */
00032 
00033 namespace std _GLIBCXX_VISIBILITY(default)
00034 {
00035 /**
00036  * @defgroup regex Regular Expressions
00037  *
00038  * A facility for performing regular expression pattern matching.
00039  * @{
00040  */
00041 
00042 /**
00043  * @namespace std::regex_constants
00044  * @brief ISO C++-0x entities sub namespace for regex.
00045  */
00046 namespace regex_constants
00047 {
00048 _GLIBCXX_BEGIN_NAMESPACE_VERSION
00049 
00050   /**
00051    * @name 5.1 Regular Expression Syntax Options
00052    */
00053   //@{
00054   enum __syntax_option
00055     {
00056       _S_icase,
00057       _S_nosubs,
00058       _S_optimize,
00059       _S_collate,
00060       _S_ECMAScript,
00061       _S_basic,
00062       _S_extended,
00063       _S_awk,
00064       _S_grep,
00065       _S_egrep,
00066       _S_syntax_last
00067     };
00068 
00069   /**
00070    * @brief This is a bitmask type indicating how to interpret the regex.
00071    *
00072    * The @c syntax_option_type is implementation defined but it is valid to
00073    * perform bitwise operations on these values and expect the right thing to
00074    * happen.
00075    *
00076    * A valid value of type syntax_option_type shall have exactly one of the
00077    * elements @c ECMAScript, @c basic, @c extended, @c awk, @c grep, @c egrep
00078    * %set.
00079    */
00080   typedef unsigned int syntax_option_type;
00081 
00082   /** 
00083    * Specifies that the matching of regular expressions against a character
00084    * sequence shall be performed without regard to case.
00085    */
00086   constexpr syntax_option_type icase      = 1 << _S_icase;
00087 
00088   /**
00089    * Specifies that when a regular expression is matched against a character
00090    * container sequence, no sub-expression matches are to be stored in the
00091    * supplied match_results structure.
00092    */
00093   constexpr syntax_option_type nosubs     = 1 << _S_nosubs;
00094 
00095   /**
00096    * Specifies that the regular expression engine should pay more attention to
00097    * the speed with which regular expressions are matched, and less to the
00098    * speed with which regular expression objects are constructed. Otherwise
00099    * it has no detectable effect on the program output.
00100    */
00101   constexpr syntax_option_type optimize   = 1 << _S_optimize;
00102 
00103   /**
00104    * Specifies that character ranges of the form [a-b] should be locale
00105    * sensitive.
00106    */
00107   constexpr syntax_option_type collate    = 1 << _S_collate;
00108 
00109   /**
00110    * Specifies that the grammar recognized by the regular expression engine is
00111    * that used by ECMAScript in ECMA-262 [Ecma International, ECMAScript
00112    * Language Specification, Standard Ecma-262, third edition, 1999], as
00113    * modified in section [28.13].  This grammar is similar to that defined
00114    * in the PERL scripting language but extended with elements found in the
00115    * POSIX regular expression grammar.
00116    */
00117   constexpr syntax_option_type ECMAScript = 1 << _S_ECMAScript;
00118 
00119   /**
00120    * Specifies that the grammar recognized by the regular expression engine is
00121    * that used by POSIX basic regular expressions in IEEE Std 1003.1-2001,
00122    * Portable Operating System Interface (POSIX), Base Definitions and
00123    * Headers, Section 9, Regular Expressions [IEEE, Information Technology --
00124    * Portable Operating System Interface (POSIX), IEEE Standard 1003.1-2001].
00125    */
00126   constexpr syntax_option_type basic      = 1 << _S_basic;
00127 
00128   /**
00129    * Specifies that the grammar recognized by the regular expression engine is
00130    * that used by POSIX extended regular expressions in IEEE Std 1003.1-2001,
00131    * Portable Operating System Interface (POSIX), Base Definitions and Headers,
00132    * Section 9, Regular Expressions.
00133    */
00134   constexpr syntax_option_type extended   = 1 << _S_extended;
00135 
00136   /**
00137    * Specifies that the grammar recognized by the regular expression engine is
00138    * that used by POSIX utility awk in IEEE Std 1003.1-2001.  This option is
00139    * identical to syntax_option_type extended, except that C-style escape
00140    * sequences are supported.  These sequences are:
00141    * \\\\, \\a, \\b, \\f, \\n, \\r, \\t , \\v, \\&apos;, &apos;,
00142    * and \\ddd (where ddd is one, two, or three octal digits).  
00143    */
00144   constexpr syntax_option_type awk        = 1 << _S_awk;
00145 
00146   /**
00147    * Specifies that the grammar recognized by the regular expression engine is
00148    * that used by POSIX utility grep in IEEE Std 1003.1-2001.  This option is
00149    * identical to syntax_option_type basic, except that newlines are treated
00150    * as whitespace.
00151    */
00152   constexpr syntax_option_type grep       = 1 << _S_grep;
00153 
00154   /**
00155    * Specifies that the grammar recognized by the regular expression engine is
00156    * that used by POSIX utility grep when given the -E option in
00157    * IEEE Std 1003.1-2001.  This option is identical to syntax_option_type 
00158    * extended, except that newlines are treated as whitespace.
00159    */
00160   constexpr syntax_option_type egrep      = 1 << _S_egrep;
00161 
00162   //@}
00163 
00164   /**
00165    * @name 5.2 Matching Rules
00166    *
00167    * Matching a regular expression against a sequence of characters [first,
00168    * last) proceeds according to the rules of the grammar specified for the
00169    * regular expression object, modified according to the effects listed
00170    * below for any bitmask elements set.
00171    *
00172    */
00173   //@{
00174 
00175   enum __match_flag
00176     {
00177       _S_not_bol,
00178       _S_not_eol,
00179       _S_not_bow,
00180       _S_not_eow,
00181       _S_any,
00182       _S_not_null,
00183       _S_continuous,
00184       _S_prev_avail,
00185       _S_sed,
00186       _S_no_copy,
00187       _S_first_only,
00188       _S_match_flag_last
00189     };
00190 
00191   /**
00192    * @brief This is a bitmask type indicating regex matching rules.
00193    *
00194    * The @c match_flag_type is implementation defined but it is valid to
00195    * perform bitwise operations on these values and expect the right thing to
00196    * happen.
00197    */
00198   typedef std::bitset<_S_match_flag_last> match_flag_type;
00199 
00200   /**
00201    * The default matching rules.
00202    */
00203   constexpr match_flag_type match_default     = 0;
00204 
00205   /**
00206    * The first character in the sequence [first, last) is treated as though it
00207    * is not at the beginning of a line, so the character (^) in the regular
00208    * expression shall not match [first, first).
00209    */
00210   constexpr match_flag_type match_not_bol     = 1 << _S_not_bol;
00211 
00212   /**
00213    * The last character in the sequence [first, last) is treated as though it
00214    * is not at the end of a line, so the character ($) in the regular
00215    * expression shall not match [last, last).
00216    */
00217   constexpr match_flag_type match_not_eol     = 1 << _S_not_eol;
00218    
00219   /**
00220    * The expression \\b is not matched against the sub-sequence
00221    * [first,first).
00222    */
00223   constexpr match_flag_type match_not_bow     = 1 << _S_not_bow;
00224    
00225   /**
00226    * The expression \\b should not be matched against the sub-sequence
00227    * [last,last).
00228    */
00229   constexpr match_flag_type match_not_eow     = 1 << _S_not_eow;
00230    
00231   /**
00232    * If more than one match is possible then any match is an acceptable
00233    * result.
00234    */
00235   constexpr match_flag_type match_any         = 1 << _S_any;
00236    
00237   /**
00238    * The expression does not match an empty sequence.
00239    */
00240   constexpr match_flag_type match_not_null    = 1 << _S_not_null;
00241    
00242   /**
00243    * The expression only matches a sub-sequence that begins at first .
00244    */
00245   constexpr match_flag_type match_continuous  = 1 << _S_continuous;
00246    
00247   /**
00248    * --first is a valid iterator position.  When this flag is set then the
00249    * flags match_not_bol and match_not_bow are ignored by the regular
00250    * expression algorithms 28.11 and iterators 28.12.
00251    */
00252   constexpr match_flag_type match_prev_avail  = 1 << _S_prev_avail;
00253 
00254   /**
00255    * When a regular expression match is to be replaced by a new string, the
00256    * new string is constructed using the rules used by the ECMAScript replace
00257    * function in ECMA- 262 [Ecma International, ECMAScript Language
00258    * Specification, Standard Ecma-262, third edition, 1999], part 15.5.4.11
00259    * String.prototype.replace. In addition, during search and replace
00260    * operations all non-overlapping occurrences of the regular expression
00261    * are located and replaced, and sections of the input that did not match
00262    * the expression are copied unchanged to the output string.
00263    * 
00264    * Format strings (from ECMA-262 [15.5.4.11]):
00265    * @li $$  The dollar-sign itself ($)
00266    * @li $&  The matched substring.
00267    * @li $`  The portion of @a string that precedes the matched substring.
00268    *         This would be match_results::prefix().
00269    * @li $'  The portion of @a string that follows the matched substring.
00270    *         This would be match_results::suffix().
00271    * @li $n  The nth capture, where n is in [1,9] and $n is not followed by a
00272    *         decimal digit.  If n <= match_results::size() and the nth capture
00273    *         is undefined, use the empty string instead.  If n >
00274    *         match_results::size(), the result is implementation-defined.
00275    * @li $nn The nnth capture, where nn is a two-digit decimal number on
00276    *         [01, 99].  If nn <= match_results::size() and the nth capture is
00277    *         undefined, use the empty string instead. If
00278    *         nn > match_results::size(), the result is implementation-defined.
00279    */
00280   constexpr match_flag_type format_default    = 0;
00281 
00282   /**
00283    * When a regular expression match is to be replaced by a new string, the
00284    * new string is constructed using the rules used by the POSIX sed utility
00285    * in IEEE Std 1003.1- 2001 [IEEE, Information Technology -- Portable
00286    * Operating System Interface (POSIX), IEEE Standard 1003.1-2001].
00287    */
00288   constexpr match_flag_type format_sed        = 1 << _S_sed;
00289 
00290   /**
00291    * During a search and replace operation, sections of the character
00292    * container sequence being searched that do not match the regular
00293    * expression shall not be copied to the output string.
00294    */
00295   constexpr match_flag_type format_no_copy    = 1 << _S_no_copy;
00296 
00297   /**
00298    * When specified during a search and replace operation, only the first
00299    * occurrence of the regular expression shall be replaced.
00300    */
00301   constexpr match_flag_type format_first_only = 1 << _S_first_only;
00302 
00303   //@}
00304 
00305 _GLIBCXX_END_NAMESPACE_VERSION
00306 } // namespace regex_constants
00307 
00308 /* @} */ // group regex
00309 } // namespace std
00310