mapnik/src/expression.cpp
2014-01-26 14:00:58 -08:00

62 lines
2 KiB
C++

/*****************************************************************************
*
* This file is part of Mapnik (c++ mapping toolkit)
*
* Copyright (C) 2011 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
*
*****************************************************************************/
// mapnik
#include <mapnik/expression.hpp>
#include <mapnik/config_error.hpp>
#include <mapnik/unicode.hpp>
#include <mapnik/expression_node_types.hpp>
#include <mapnik/expression_grammar.hpp>
#include <boost/spirit/include/qi.hpp>
// boost
namespace mapnik
{
expression_ptr parse_expression(std::string const& str, std::string const& encoding)
{
transcoder tr(encoding);
expression_grammar<std::string::const_iterator> g(tr);
return parse_expression(str, g);
}
expression_ptr parse_expression(std::string const& str,
mapnik::expression_grammar<std::string::const_iterator> const& g)
{
boost::spirit::standard_wide::space_type space;
expression_ptr node = std::make_shared<expr_node>();
std::string::const_iterator itr = str.begin();
std::string::const_iterator end = str.end();
bool r = boost::spirit::qi::phrase_parse(itr, end, g, space, *node);
if (r && itr == end)
{
return node;
}
else
{
throw config_error( "Failed to parse expression: \"" + str + "\"" );
}
}
}