// In header: <boost/log/sinks/event_log_backend.hpp>

template<typename CharT, typename AttributeValueT = int> 
class basic_custom_event_category_mapping :
  public basic_custom_mapping< CharT, event_category_t, AttributeValueT >
{
public:
  // types
  typedef base_type::string_type string_type;  // String type. 

  // construct/copy/destruct
  explicit basic_custom_event_category_mapping(string_type const &);
};