mapnik/include/filter_expression.hpp
2006-07-24 20:08:32 +00:00

65 lines
1.9 KiB
C++

/*****************************************************************************
*
* This file is part of Mapnik (c++ mapping toolkit)
*
* Copyright (C) 2006 Artem Pavlenko
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 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