-protected:
- std::string string_node (std::string);
- std::string optional_string_node (std::string);
- ContentKind kind_node (std::string);
- Fraction fraction_node (std::string);
- int64_t int64_node (std::string);
- int64_t optional_int64_node (std::string);
- float float_node (std::string);
- void ignore_node (std::string);
- void done ();