tuple.cpp 1.5 KB

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  1. /*=============================================================================
  2. Copyright (c) 2019 Tom Tan
  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. #include <boost/config/warning_disable.hpp>
  7. #include <boost/spirit/home/x3.hpp>
  8. #include <boost/fusion/adapted/std_tuple.hpp>
  9. #include <iostream>
  10. #include <tuple>
  11. #include <string>
  12. //
  13. // X3 does not support more than one attribute anymore in the parse function,
  14. // this example show how to wrap multiple attributes into one leveraging std::tuple.
  15. //
  16. std::tuple<uint32_t, uint32_t, uint32_t> parse_message_prefix_revision(const std::string &s)
  17. {
  18. namespace x3 = boost::spirit::x3;
  19. auto const uint_3_digits = x3::uint_parser<std::uint32_t, 10, 3, 3>{};
  20. auto const uint_4_digits = x3::uint_parser<std::uint32_t, 10, 4, 4>{};
  21. auto iter = s.cbegin();
  22. auto end_iter = s.cend();
  23. std::tuple<uint32_t, uint32_t, uint32_t> length_id_revision;
  24. x3::parse(iter, end_iter,
  25. uint_4_digits >> uint_4_digits >> uint_3_digits,
  26. length_id_revision);
  27. return length_id_revision;
  28. }
  29. int main()
  30. {
  31. std::string s = "00200060001";
  32. std::cout << "parsing " << s << '\n';
  33. auto [len, id, rev] = parse_message_prefix_revision(s);
  34. std::cout << "length = " << len << '\n'
  35. << "id = " << id << '\n'
  36. << "revision =" << rev;
  37. }