mapnik/include/filter_expression.hpp
2005-06-14 15:06:59 +00:00

61 lines
1.6 KiB
C++

/* This file is part of Mapnik (c++ mapping toolkit)
* Copyright (C) 2005 Artem Pavlenko
*
* Mapnik 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 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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*/
//$Id$
#ifndef FILTER_TO_STRING_HPP
#define FILTER_TO_STRING_HPP
#include "filter.hpp"
#include "expression.hpp"
#include <set>
namespace mapnik
{
template <typename FeatureT>
class filter_to_string : public filter_visitor<FeatureT>
{
private:
std::string text_;
public:
filter_to_string() {}
void visit(filter<FeatureT>& /*filter*/)
{
//not interested
}
void visit(expression<FeatureT>& exp)
{
property<FeatureT>* pf;
if ((pf = dynamic_cast<property<FeatureT>*>(&exp)))
{
names_.insert(pf->name());
}
}
std::string const& text() const
{
return text_;
}
virtual ~filter_to_string() {}
private:
filter_to_string(filter_to_string const&);
filter_to_string& operator=(filter_to_string const&);
};
}
#endif //FILTER_TO_STRING