// In header: <boost/log/sinks/event_log_backend.hpp>
template<typename CharT> 
class basic_event_log_backend :
  public basic_sink_backend< synchronized_feeding >
{
public:
  // types
  typedef CharT                          char_type;                   // Character type. 
  typedef std::basic_string< char_type > string_type;                 // String type. 
  typedef std::vector< string_type >     insertion_list;              // Type of the composed insertions list. 
  typedef unspecified                    event_type_mapper_type;      // Mapper type for the event type. 
  typedef unspecified                    event_category_mapper_type;  // Mapper type for the event category. 
  typedef unspecified                    event_composer_type;         // Event composer type. 
  // construct/copy/destruct
  template<typename T> 
    explicit basic_event_log_backend(std::basic_string< T > const &);
  explicit basic_event_log_backend(filesystem::path const &);
  template<typename... ArgsT> 
    explicit basic_event_log_backend(ArgsT...const &);
  ~basic_event_log_backend();
  // public member functions
  void consume(record_view const &);
  void set_event_type_mapper(event_type_mapper_type const &);
  void set_event_category_mapper(event_category_mapper_type const &);
  void set_event_composer(event_composer_type const &);
  // public static functions
  static string_type get_default_log_name();
  static string_type get_default_source_name();
};