regex_constants.h

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00001 // class template regex -*- C++ -*-
00002 
00003 // Copyright (C) 2010 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  *  You should not attempt to use it directly.
00031  */
00032 
00033 namespace std
00034 {
00035 
00036 /**
00037  * @namespace std::regex_constants
00038  * @brief ISO C++-0x entities sub namespace for regex.
00039  */
00040 namespace regex_constants
00041 {
00042   /**
00043    * @name 5.1 Regular Expression Syntax Options
00044    */
00045   //@{
00046   enum __syntax_option
00047     {
00048       _S_icase,
00049       _S_nosubs,
00050       _S_optimize,
00051       _S_collate,
00052       _S_ECMAScript,
00053       _S_basic,
00054       _S_extended,
00055       _S_awk,
00056       _S_grep,
00057       _S_egrep,
00058       _S_syntax_last
00059     };
00060 
00061   /**
00062    * @brief This is a bitmask type indicating how to interpret the regex.
00063    *
00064    * The @c syntax_option_type is implementation defined but it is valid to
00065    * perform bitwise operations on these values and expect the right thing to
00066    * happen.
00067    *
00068    * A valid value of type syntax_option_type shall have exactly one of the
00069    * elements @c ECMAScript, @c basic, @c extended, @c awk, @c grep, @c egrep
00070    * %set.
00071    */
00072   typedef unsigned int syntax_option_type;
00073 
00074   /** 
00075    * Specifies that the matching of regular expressions against a character
00076    * sequence shall be performed without regard to case.
00077    */
00078   static const syntax_option_type icase      = 1 << _S_icase;
00079 
00080   /**
00081    * Specifies that when a regular expression is matched against a character
00082    * container sequence, no sub-expression matches are to be stored in the
00083    * supplied match_results structure.
00084    */
00085   static const syntax_option_type nosubs     = 1 << _S_nosubs;
00086 
00087   /**
00088    * Specifies that the regular expression engine should pay more attention to
00089    * the speed with which regular expressions are matched, and less to the
00090    * speed with which regular expression objects are constructed. Otherwise
00091    * it has no detectable effect on the program output.
00092    */
00093   static const syntax_option_type optimize   = 1 << _S_optimize;
00094 
00095   /**
00096    * Specifies that character ranges of the form [a-b] should be locale
00097    * sensitive.
00098    */
00099   static const syntax_option_type collate    = 1 << _S_collate;
00100 
00101   /**
00102    * Specifies that the grammar recognized by the regular expression engine is
00103    * that used by ECMAScript in ECMA-262 [Ecma International, ECMAScript
00104    * Language Specification, Standard Ecma-262, third edition, 1999], as
00105    * modified in section [28.13].  This grammar is similar to that defined
00106    * in the PERL scripting language but extended with elements found in the
00107    * POSIX regular expression grammar.
00108    */
00109   static const syntax_option_type ECMAScript = 1 << _S_ECMAScript;
00110 
00111   /**
00112    * Specifies that the grammar recognized by the regular expression engine is
00113    * that used by POSIX basic regular expressions in IEEE Std 1003.1-2001,
00114    * Portable Operating System Interface (POSIX), Base Definitions and
00115    * Headers, Section 9, Regular Expressions [IEEE, Information Technology --
00116    * Portable Operating System Interface (POSIX), IEEE Standard 1003.1-2001].
00117    */
00118   static const syntax_option_type basic      = 1 << _S_basic;
00119 
00120   /**
00121    * Specifies that the grammar recognized by the regular expression engine is
00122    * that used by POSIX extended regular expressions in IEEE Std 1003.1-2001,
00123    * Portable Operating System Interface (POSIX), Base Definitions and Headers,
00124    * Section 9, Regular Expressions.
00125    */
00126   static const syntax_option_type extended   = 1 << _S_extended;
00127 
00128   /**
00129    * Specifies that the grammar recognized by the regular expression engine is
00130    * that used by POSIX utility awk in IEEE Std 1003.1-2001.  This option is
00131    * identical to syntax_option_type extended, except that C-style escape
00132    * sequences are supported.  These sequences are:
00133    * \\\\, \\a, \\b, \\f, \\n, \\r, \\t , \\v, \\&apos;, &apos;,
00134    * and \\ddd (where ddd is one, two, or three octal digits).  
00135    */
00136   static const syntax_option_type awk        = 1 << _S_awk;
00137 
00138   /**
00139    * Specifies that the grammar recognized by the regular expression engine is
00140    * that used by POSIX utility grep in IEEE Std 1003.1-2001.  This option is
00141    * identical to syntax_option_type basic, except that newlines are treated
00142    * as whitespace.
00143    */
00144   static const syntax_option_type grep       = 1 << _S_grep;
00145 
00146   /**
00147    * Specifies that the grammar recognized by the regular expression engine is
00148    * that used by POSIX utility grep when given the -E option in
00149    * IEEE Std 1003.1-2001.  This option is identical to syntax_option_type 
00150    * extended, except that newlines are treated as whitespace.
00151    */
00152   static const syntax_option_type egrep      = 1 << _S_egrep;
00153 
00154   //@}
00155 
00156   /**
00157    * @name 5.2 Matching Rules
00158    *
00159    * Matching a regular expression against a sequence of characters [first,
00160    * last) proceeds according to the rules of the grammar specified for the
00161    * regular expression object, modified according to the effects listed
00162    * below for any bitmask elements set.
00163    *
00164    */
00165   //@{
00166 
00167   enum __match_flag
00168     {
00169       _S_not_bol,
00170       _S_not_eol,
00171       _S_not_bow,
00172       _S_not_eow,
00173       _S_any,
00174       _S_not_null,
00175       _S_continuous,
00176       _S_prev_avail,
00177       _S_sed,
00178       _S_no_copy,
00179       _S_first_only,
00180       _S_match_flag_last
00181     };
00182 
00183   /**
00184    * @brief This is a bitmask type indicating regex matching rules.
00185    *
00186    * The @c match_flag_type is implementation defined but it is valid to
00187    * perform bitwise operations on these values and expect the right thing to
00188    * happen.
00189    */
00190   typedef std::bitset<_S_match_flag_last> match_flag_type;
00191 
00192   /**
00193    * The default matching rules.
00194    */
00195   static const match_flag_type match_default     = 0;
00196 
00197   /**
00198    * The first character in the sequence [first, last) is treated as though it
00199    * is not at the beginning of a line, so the character (^) in the regular
00200    * expression shall not match [first, first).
00201    */
00202   static const match_flag_type match_not_bol     = 1 << _S_not_bol;
00203 
00204   /**
00205    * The last character in the sequence [first, last) is treated as though it
00206    * is not at the end of a line, so the character ($) in the regular
00207    * expression shall not match [last, last).
00208    */
00209   static const match_flag_type match_not_eol     = 1 << _S_not_eol;
00210    
00211   /**
00212    * The expression \\b is not matched against the sub-sequence
00213    * [first,first).
00214    */
00215   static const match_flag_type match_not_bow     = 1 << _S_not_bow;
00216    
00217   /**
00218    * The expression \\b should not be matched against the sub-sequence
00219    * [last,last).
00220    */
00221   static const match_flag_type match_not_eow     = 1 << _S_not_eow;
00222    
00223   /**
00224    * If more than one match is possible then any match is an acceptable
00225    * result.
00226    */
00227   static const match_flag_type match_any         = 1 << _S_any;
00228    
00229   /**
00230    * The expression does not match an empty sequence.
00231    */
00232   static const match_flag_type match_not_null    = 1 << _S_not_null;
00233    
00234   /**
00235    * The expression only matches a sub-sequence that begins at first .
00236    */
00237   static const match_flag_type match_continuous  = 1 << _S_continuous;
00238    
00239   /**
00240    * --first is a valid iterator position.  When this flag is set then the
00241    * flags match_not_bol and match_not_bow are ignored by the regular
00242    * expression algorithms 7.11 and iterators 7.12.
00243    */
00244   static const match_flag_type match_prev_avail  = 1 << _S_prev_avail;
00245 
00246   /**
00247    * When a regular expression match is to be replaced by a new string, the
00248    * new string is constructed using the rules used by the ECMAScript replace
00249    * function in ECMA- 262 [Ecma International, ECMAScript Language
00250    * Specification, Standard Ecma-262, third edition, 1999], part 15.5.4.11
00251    * String.prototype.replace. In addition, during search and replace
00252    * operations all non-overlapping occurrences of the regular expression
00253    * are located and replaced, and sections of the input that did not match
00254    * the expression are copied unchanged to the output string.
00255    * 
00256    * Format strings (from ECMA-262 [15.5.4.11]):
00257    * @li $$  The dollar-sign itself ($)
00258    * @li $&  The matched substring.
00259    * @li $`  The portion of @a string that precedes the matched substring.
00260    *         This would be match_results::prefix().
00261    * @li $'  The portion of @a string that follows the matched substring.
00262    *         This would be match_results::suffix().
00263    * @li $n  The nth capture, where n is in [1,9] and $n is not followed by a
00264    *         decimal digit.  If n <= match_results::size() and the nth capture
00265    *         is undefined, use the empty string instead.  If n >
00266    *         match_results::size(), the result is implementation-defined.
00267    * @li $nn The nnth capture, where nn is a two-digit decimal number on
00268    *         [01, 99].  If nn <= match_results::size() and the nth capture is
00269    *         undefined, use the empty string instead. If
00270    *         nn > match_results::size(), the result is implementation-defined.
00271    */
00272   static const match_flag_type format_default    = 0;
00273 
00274   /**
00275    * When a regular expression match is to be replaced by a new string, the
00276    * new string is constructed using the rules used by the POSIX sed utility
00277    * in IEEE Std 1003.1- 2001 [IEEE, Information Technology -- Portable
00278    * Operating System Interface (POSIX), IEEE Standard 1003.1-2001].
00279    */
00280   static const match_flag_type format_sed        = 1 << _S_sed;
00281 
00282   /**
00283    * During a search and replace operation, sections of the character
00284    * container sequence being searched that do not match the regular
00285    * expression shall not be copied to the output string.
00286    */
00287   static const match_flag_type format_no_copy    = 1 << _S_no_copy;
00288 
00289   /**
00290    * When specified during a search and replace operation, only the first
00291    * occurrence of the regular expression shall be replaced.
00292    */
00293   static const match_flag_type format_first_only = 1 << _S_first_only;
00294 
00295   //@}
00296 
00297 } // namespace regex_constants
00298 } // namespace std
00299