// In header: <boost/log/sources/severity_channel_logger.hpp>
template<typename LevelT = int, typename ChannelT = std::string> 
class severity_channel_logger_mt : public basic_composite_logger< char, severity_channel_logger_mt< LevelT, ChannelT >, multi_thread_model< implementation_defined >, features< severity< LevelT >, channel< ChannelT > > >
{
public:
  // construct/copy/destruct
  severity_channel_logger_mt();
  severity_channel_logger_mt(severity_channel_logger_mt const &);
  template<typename... ArgsT> 
    explicit severity_channel_logger_mt(ArgsT...const &);
  severity_channel_logger_mt & operator=(severity_channel_logger_mt const &);
};