| /*============================================================================= |
| Copyright (c) 2003 Sam Nabialek |
| Copyright (c) 2001-2010 Joel de Guzman |
| |
| Distributed under the Boost Software License, Version 1.0. (See accompanying |
| file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt) |
| =============================================================================*/ |
| /////////////////////////////////////////////////////////////////////////////// |
| // |
| // The Nabialek trick. |
| // |
| // [ Sam Nabialek; Somewhere, sometime in 2003... ] spirit1 |
| // [ JDG November 17, 2009 ] spirit2 |
| // |
| /////////////////////////////////////////////////////////////////////////////// |
| |
| #include <boost/config/warning_disable.hpp> |
| #include <boost/spirit/include/qi.hpp> |
| #include <boost/spirit/include/phoenix_operator.hpp> |
| #include <iostream> |
| #include <string> |
| |
| namespace client |
| { |
| namespace qi = boost::spirit::qi; |
| namespace ascii = boost::spirit::ascii; |
| |
| /////////////////////////////////////////////////////////////////////////////// |
| // Our nabialek_trick grammar |
| /////////////////////////////////////////////////////////////////////////////// |
| template <typename Iterator> |
| struct nabialek_trick : qi::grammar< |
| Iterator, ascii::space_type, qi::locals<qi::rule<Iterator, ascii::space_type> > > |
| { |
| nabialek_trick() : nabialek_trick::base_type(start) |
| { |
| using ascii::alnum; |
| using qi::lexeme; |
| using qi::lazy; |
| using qi::_a; |
| using qi::_1; |
| |
| id = lexeme[*(ascii::alnum | '_')]; |
| one = id; |
| two = id >> ',' >> id; |
| |
| keyword.add |
| ("one", one) |
| ("two", two) |
| ; |
| |
| start = *(keyword[_a = _1] >> lazy(_a)); |
| } |
| |
| qi::rule<Iterator, ascii::space_type> id, one, two; |
| qi::rule<Iterator, ascii::space_type, qi::locals<qi::rule<Iterator, ascii::space_type> > > start; |
| qi::symbols<char, qi::rule<Iterator, ascii::space_type> > keyword; |
| }; |
| } |
| |
| /////////////////////////////////////////////////////////////////////////////// |
| // Main program |
| /////////////////////////////////////////////////////////////////////////////// |
| int |
| main() |
| { |
| using boost::spirit::ascii::space; |
| typedef std::string::const_iterator iterator_type; |
| typedef client::nabialek_trick<iterator_type> nabialek_trick; |
| |
| nabialek_trick g; // Our grammar |
| |
| std::string str = "one only\none again\ntwo first,second"; |
| std::string::const_iterator iter = str.begin(); |
| std::string::const_iterator end = str.end(); |
| bool r = phrase_parse(iter, end, g, space); |
| |
| if (r && iter == end) |
| { |
| std::cout << "-------------------------\n"; |
| std::cout << "Parsing succeeded\n"; |
| std::cout << "-------------------------\n"; |
| } |
| else |
| { |
| std::string rest(iter, end); |
| std::cout << "-------------------------\n"; |
| std::cout << "Parsing failed\n"; |
| std::cout << "stopped at: \": " << rest << "\"\n"; |
| std::cout << "-------------------------\n"; |
| } |
| |
| return 0; |
| } |
| |
| |