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/* omega.h: Main header for omega
*
* Copyright 1999,2000,2001 BrightStation PLC
* Copyright 2001 Lemur Consulting Ltd
* Copyright 2001,2002 Ananova Ltd
* Copyright 2002,2003,2006 Olly Betts
*
* This program 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 2 of the
* License, or (at your option) any later version.
*
* This program 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 St, Fifth Floor, Boston, MA 02110-1301
* USA
*/
#include <config.h>
#include <xapian.h>
#define PROGRAM_NAME "omega"
#include "configfile.h"
#include <map>
#include <vector>
using namespace std;
const char filter_sep = '-';
// Any choice of character for filter_sep could conceivably lead to
// false positives, but the situation is contrived, and just means that if
// someone changed a filter, the first page wouldn't be forced.
// That's hardly the end of the world...
extern string query_string;
extern string dbname;
extern string fmtname;
extern string filters;
extern Xapian::Database db;
extern Xapian::Enquire * enquire;
extern Xapian::RSet rset;
extern Xapian::docid topdoc;
extern Xapian::docid hits_per_page;
extern Xapian::docid min_hits;
extern int threshold;
extern bool sort_numeric;
extern Xapian::valueno sort_key;
extern bool sort_ascending;
extern Xapian::valueno collapse_key;
extern bool collapse;
extern map<string, string> option;
extern string date_start, date_end, date_span;
extern const string default_dbname;
class ExpandDeciderOmega : public Xapian::ExpandDecider {
private:
Xapian::Database db;
public:
ExpandDeciderOmega(const Xapian::Database &db_) : db(db_) { }
int operator()(const string & tname) const {
// only suggest 4 or more letter words for now to
// avoid italian problems FIXME: fix this at index time
if (tname.length() <= 3) return false;
// Ignore a term that only occurs once (a hapax) since it's not
// useful for finding related documents - it only occurs in a
// document that's already been marked as relevant
if (db.get_termfreq(tname) <= 1) return false;
// Raw terms are OK, otherwise avoid terms with a prefix or with a
// space in
if (tname[0] == 'R') return true;
if (isupper(static_cast<unsigned char>(tname[0])) ||
tname.find(' ') != string::npos) {
return false;
}
return true;
}
};
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