ceph/src/boost/libs/spirit/example/qi/iter_pos_parser.cpp

   1 //  Copyright (c) 2001-2010 Hartmut Kaiser
   2 //
   3 //  Distributed under the Boost Software License, Version 1.0. (See accompanying
   4 //  file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
   5
   6 //  The purpose of this example is to show how a simple custom primitive parser
   7 //  component can be written. We develop a custom parser exposing the current
   8 //  iterator position as its attribute.
   9 //
  10 //  For more information see: http://spirit.sourceforge.net/home/?page_id=567
  11
  12 #include <boost/spirit/include/qi_parse_attr.hpp>
  13 #include <boost/spirit/include/qi_char.hpp>
  14 #include <boost/spirit/include/qi_operator.hpp>
  15
  16 #include <string>
  17 #include "iter_pos.hpp"
  18
  19 namespace qi = boost::spirit::qi;
  20
  21 int main()
  22 {
  23     using custom_parser::iter_pos;
  24
  25     std::string prefix, suffix;           // attributes receiving the
  26     std::string::iterator position;       // parsed values
  27
  28     std::string input("prefix1234567");
  29     std::string::iterator first = input.begin();
  30     bool result =
  31         qi::parse(first, input.end()
  32           , +qi::alpha >> iter_pos >> +qi::digit
  33           , prefix, position, suffix);
  34
  35     if (result)
  36     {
  37         std::cout << "-------------------------------- \n";
  38         std::cout << "Parsing succeeded\n";
  39         std::cout << "prefix is: " << prefix << "\n";
  40         std::cout << "suffix is: " << suffix << "\n";
  41         std::cout << "position is: " << std::distance(input.begin(), position) << "\n";
  42         std::cout << "-------------------------------- \n";
  43     }
  44     else
  45     {
  46         std::cout << "-------------------------------- \n";
  47         std::cout << "Parsing failed\n";
  48         std::cout << "-------------------------------- \n";
  49     }
  50     return 0;
  51 }