anchor.diff:  %% Producer API
   -export([ start_link_producer/1
           , start_link_producer/3
  +        , start_producer/1
  +        , start_producer/3
           , stop_producer/1
           , produce/3
           , produce/4
  
positive.code:       ok
    end.
  
  %% @doc Start consumer process
  -spec start_link_consumer([host()], binary(), integer()) ->
                          {ok, pid()} | {error, any()}.
  
negative.code: 
  %% Consumer API
  -export([ start_link_consumer/3
          , start_consumer/3
          , stop_consumer/1
          , consume/2
          , consume/6
  