multi_pass.cpp 1.6 KB

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  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. #include <iostream>
  6. #include <fstream>
  7. #include <vector>
  8. #include <boost/spirit/include/qi.hpp>
  9. #include <boost/spirit/include/support_multi_pass.hpp>
  10. ///////////////////////////////////////////////////////////////////////////////
  11. ///////////////////////////////////////////////////////////////////////////////
  12. //[tutorial_multi_pass
  13. int main()
  14. {
  15. namespace spirit = boost::spirit;
  16. using spirit::ascii::space;
  17. using spirit::ascii::char_;
  18. using spirit::qi::double_;
  19. using spirit::qi::eol;
  20. std::ifstream in("multi_pass.txt"); // we get our input from this file
  21. if (!in.is_open()) {
  22. std::cout << "Could not open input file: 'multi_pass.txt'" << std::endl;
  23. return -1;
  24. }
  25. typedef std::istreambuf_iterator<char> base_iterator_type;
  26. spirit::multi_pass<base_iterator_type> first =
  27. spirit::make_default_multi_pass(base_iterator_type(in));
  28. std::vector<double> v;
  29. bool result = spirit::qi::phrase_parse(first
  30. , spirit::make_default_multi_pass(base_iterator_type())
  31. , double_ >> *(',' >> double_) // recognize list of doubles
  32. , space | '#' >> *(char_ - eol) >> eol // comment skipper
  33. , v); // data read from file
  34. if (!result) {
  35. std::cout << "Failed parsing input file!" << std::endl;
  36. return -2;
  37. }
  38. std::cout << "Successfully parsed input file!" << std::endl;
  39. return 0;
  40. }
  41. //]