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#ifndef LPC_MATCH_H1105564052_INCLUDE_GUARD_
#define LPC_MATCH_H1105564052_INCLUDE_GUARD_
/* This file is part of indexlib.
* Copyright (C) 2005 Luís Pedro Coelho <luis@luispedro.org>
*
* Indexlib is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License, version 2, as
* published by the Free Software Foundation and available as file
* GPL_V2 which is distributed along with indexlib.
*
* Indexlib 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.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
* MA 02110-1301, USA
*
* In addition, as a special exception, the copyright holders give
* permission to link the code of this program with any edition of
* the Qt library by Trolltech AS, Norway (or with modified versions
* of Qt that use the same license as Qt), and distribute linked
* combinations including the two. You must obey the GNU General
* Public License in all respects for all of the code used other than
* Qt. If you modify this file, you may extend this exception to
* your version of the file, but you are not obligated to do so. If
* you do not wish to do so, delete this exception statement from
* your version.
*/
#include <string>
#include <vector>
#include <map>
namespace indexlib {
/**
* \brief A class for string matching
*
* This class represents a pattern in a pre-processed form so that searching for it in larger textes is
* very fast. This allows for a very fast way to ask "does this pattern appear in this text?"
*
* The implementation uses the shift-or algorithm which is very fast, but especially designed for
* patterns which are shorter than the number of bits in a word ( 32 bits on most architechtures ). For
* larger patterns, the first 32 characters are matched using shift-or and the next characters are strcmp()ed.
* Even for patterns larger than 32 characters, this should be a fast strategy.
*/
class Match {
public:
enum flags { caseinsensitive = 1 };
/** Construct an object to match string \param pattern
*/
Match( std::string pattern, unsigned flags = 0 );
~Match();
/**
* Returns true if the pattern appears in \param string
* It has no memory
*/
bool process( const char* string ) const;
bool process( std::string str ) const { return process( str.c_str() ); }
private:
typedef std::vector<unsigned> masks_type;
masks_type masks_;
unsigned hot_bit_;
bool caseinsensitive_;
std::string pattern_rest_;
};
}
#endif /* LPC_MATCH_H1105564052_INCLUDE_GUARD_ */
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