regex_constants.h
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// class template regex -*- C++ -*-
// Copyright (C) 2010-2013 Free Software Foundation, Inc.
//
// This file is part of the GNU ISO C++ Library. This library is free
// software; you can redistribute it and/or modify it under the
// terms of the GNU General Public License as published by the
// Free Software Foundation; either version 3, or (at your option)
// any later version.
// This library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
// Under Section 7 of GPL version 3, you are granted additional
// permissions described in the GCC Runtime Library Exception, version
// 3.1, as published by the Free Software Foundation.
// You should have received a copy of the GNU General Public License and
// a copy of the GCC Runtime Library Exception along with this program;
// see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
// <http://www.gnu.org/licenses/>.
/**
* @file bits/regex_constants.h
* @brief Constant definitions for the std regex library.
*
* This is an internal header file, included by other library headers.
* Do not attempt to use it directly. @headername{regex}
*/
namespace std _GLIBCXX_VISIBILITY(default)
{
/**
* @defgroup regex Regular Expressions
*
* A facility for performing regular expression pattern matching.
* @{
*/
/**
* @namespace std::regex_constants
* @brief ISO C++-0x entities sub namespace for regex.
*/
namespace regex_constants
{
_GLIBCXX_BEGIN_NAMESPACE_VERSION
/**
* @name 5.1 Regular Expression Syntax Options
*/
//@{
enum __syntax_option
{
_S_icase,
_S_nosubs,
_S_optimize,
_S_collate,
_S_ECMAScript,
_S_basic,
_S_extended,
_S_awk,
_S_grep,
_S_egrep,
_S_syntax_last
};
/**
* @brief This is a bitmask type indicating how to interpret the regex.
*
* The @c syntax_option_type is implementation defined but it is valid to
* perform bitwise operations on these values and expect the right thing to
* happen.
*
* A valid value of type syntax_option_type shall have exactly one of the
* elements @c ECMAScript, @c basic, @c extended, @c awk, @c grep, @c egrep
* %set.
*/
typedef unsigned int syntax_option_type;
/**
* Specifies that the matching of regular expressions against a character
* sequence shall be performed without regard to case.
*/
constexpr syntax_option_type icase = 1 << _S_icase;
/**
* Specifies that when a regular expression is matched against a character
* container sequence, no sub-expression matches are to be stored in the
* supplied match_results structure.
*/
constexpr syntax_option_type nosubs = 1 << _S_nosubs;
/**
* Specifies that the regular expression engine should pay more attention to
* the speed with which regular expressions are matched, and less to the
* speed with which regular expression objects are constructed. Otherwise
* it has no detectable effect on the program output.
*/
constexpr syntax_option_type optimize = 1 << _S_optimize;
/**
* Specifies that character ranges of the form [a-b] should be locale
* sensitive.
*/
constexpr syntax_option_type collate = 1 << _S_collate;
/**
* Specifies that the grammar recognized by the regular expression engine is
* that used by ECMAScript in ECMA-262 [Ecma International, ECMAScript
* Language Specification, Standard Ecma-262, third edition, 1999], as
* modified in section [28.13]. This grammar is similar to that defined
* in the PERL scripting language but extended with elements found in the
* POSIX regular expression grammar.
*/
constexpr syntax_option_type ECMAScript = 1 << _S_ECMAScript;
/**
* Specifies that the grammar recognized by the regular expression engine is
* that used by POSIX basic regular expressions in IEEE Std 1003.1-2001,
* Portable Operating System Interface (POSIX), Base Definitions and
* Headers, Section 9, Regular Expressions [IEEE, Information Technology --
* Portable Operating System Interface (POSIX), IEEE Standard 1003.1-2001].
*/
constexpr syntax_option_type basic = 1 << _S_basic;
/**
* Specifies that the grammar recognized by the regular expression engine is
* that used by POSIX extended regular expressions in IEEE Std 1003.1-2001,
* Portable Operating System Interface (POSIX), Base Definitions and Headers,
* Section 9, Regular Expressions.
*/
constexpr syntax_option_type extended = 1 << _S_extended;
/**
* Specifies that the grammar recognized by the regular expression engine is
* that used by POSIX utility awk in IEEE Std 1003.1-2001. This option is
* identical to syntax_option_type extended, except that C-style escape
* sequences are supported. These sequences are:
* \\\\, \\a, \\b, \\f, \\n, \\r, \\t , \\v, \\&apos;, &apos;,
* and \\ddd (where ddd is one, two, or three octal digits).
*/
constexpr syntax_option_type awk = 1 << _S_awk;
/**
* Specifies that the grammar recognized by the regular expression engine is
* that used by POSIX utility grep in IEEE Std 1003.1-2001. This option is
* identical to syntax_option_type basic, except that newlines are treated
* as whitespace.
*/
constexpr syntax_option_type grep = 1 << _S_grep;
/**
* Specifies that the grammar recognized by the regular expression engine is
* that used by POSIX utility grep when given the -E option in
* IEEE Std 1003.1-2001. This option is identical to syntax_option_type
* extended, except that newlines are treated as whitespace.
*/
constexpr syntax_option_type egrep = 1 << _S_egrep;
//@}
/**
* @name 5.2 Matching Rules
*
* Matching a regular expression against a sequence of characters [first,
* last) proceeds according to the rules of the grammar specified for the
* regular expression object, modified according to the effects listed
* below for any bitmask elements set.
*
*/
//@{
enum __match_flag
{
_S_not_bol,
_S_not_eol,
_S_not_bow,
_S_not_eow,
_S_any,
_S_not_null,
_S_continuous,
_S_prev_avail,
_S_sed,
_S_no_copy,
_S_first_only,
_S_match_flag_last
};
/**
* @brief This is a bitmask type indicating regex matching rules.
*
* The @c match_flag_type is implementation defined but it is valid to
* perform bitwise operations on these values and expect the right thing to
* happen.
*/
typedef std::bitset<_S_match_flag_last> match_flag_type;
/**
* The default matching rules.
*/
constexpr match_flag_type match_default = 0;
/**
* The first character in the sequence [first, last) is treated as though it
* is not at the beginning of a line, so the character (^) in the regular
* expression shall not match [first, first).
*/
constexpr match_flag_type match_not_bol = 1 << _S_not_bol;
/**
* The last character in the sequence [first, last) is treated as though it
* is not at the end of a line, so the character ($) in the regular
* expression shall not match [last, last).
*/
constexpr match_flag_type match_not_eol = 1 << _S_not_eol;
/**
* The expression \\b is not matched against the sub-sequence
* [first,first).
*/
constexpr match_flag_type match_not_bow = 1 << _S_not_bow;
/**
* The expression \\b should not be matched against the sub-sequence
* [last,last).
*/
constexpr match_flag_type match_not_eow = 1 << _S_not_eow;
/**
* If more than one match is possible then any match is an acceptable
* result.
*/
constexpr match_flag_type match_any = 1 << _S_any;
/**
* The expression does not match an empty sequence.
*/
constexpr match_flag_type match_not_null = 1 << _S_not_null;
/**
* The expression only matches a sub-sequence that begins at first .
*/
constexpr match_flag_type match_continuous = 1 << _S_continuous;
/**
* --first is a valid iterator position. When this flag is set then the
* flags match_not_bol and match_not_bow are ignored by the regular
* expression algorithms 28.11 and iterators 28.12.
*/
constexpr match_flag_type match_prev_avail = 1 << _S_prev_avail;
/**
* When a regular expression match is to be replaced by a new string, the
* new string is constructed using the rules used by the ECMAScript replace
* function in ECMA- 262 [Ecma International, ECMAScript Language
* Specification, Standard Ecma-262, third edition, 1999], part 15.5.4.11
* String.prototype.replace. In addition, during search and replace
* operations all non-overlapping occurrences of the regular expression
* are located and replaced, and sections of the input that did not match
* the expression are copied unchanged to the output string.
*
* Format strings (from ECMA-262 [15.5.4.11]):
* @li $$ The dollar-sign itself ($)
* @li $& The matched substring.
* @li $` The portion of @a string that precedes the matched substring.
* This would be match_results::prefix().
* @li $' The portion of @a string that follows the matched substring.
* This would be match_results::suffix().
* @li $n The nth capture, where n is in [1,9] and $n is not followed by a
* decimal digit. If n <= match_results::size() and the nth capture
* is undefined, use the empty string instead. If n >
* match_results::size(), the result is implementation-defined.
* @li $nn The nnth capture, where nn is a two-digit decimal number on
* [01, 99]. If nn <= match_results::size() and the nth capture is
* undefined, use the empty string instead. If
* nn > match_results::size(), the result is implementation-defined.
*/
constexpr match_flag_type format_default = 0;
/**
* When a regular expression match is to be replaced by a new string, the
* new string is constructed using the rules used by the POSIX sed utility
* in IEEE Std 1003.1- 2001 [IEEE, Information Technology -- Portable
* Operating System Interface (POSIX), IEEE Standard 1003.1-2001].
*/
constexpr match_flag_type format_sed = 1 << _S_sed;
/**
* During a search and replace operation, sections of the character
* container sequence being searched that do not match the regular
* expression shall not be copied to the output string.
*/
constexpr match_flag_type format_no_copy = 1 << _S_no_copy;
/**
* When specified during a search and replace operation, only the first
* occurrence of the regular expression shall be replaced.
*/
constexpr match_flag_type format_first_only = 1 << _S_first_only;
//@}
_GLIBCXX_END_NAMESPACE_VERSION
} // namespace regex_constants
/* @} */ // group regex
} // namespace std