anchor.diff:          [Channel, Payload] -> ok;
           [Channel]          -> Payload = <<>>
       end,
  -    notify_async(State, {notification, Channel, Pid, Payload}),
  -    {noreply, State}.
  +    State2 = notify_async(State, {notification, Channel, Pid, Payload}),
  +    {noreply, State2}.
  
positive.code: 
  %% NoticeResponse
  on_message({$N, Data}, State) ->
      notify_async(State, {notice, pgsql_wire:decode_error(Data)}),
      {noreply, State};
  
  %% ParameterStatus
  on_message({$S, Data}, State) ->
  
negative.code:     case queue:get(Q) of
          {{cast, From, Ref}, _} ->
              From ! {Ref, Result};
          {{incremental, From, Ref}, _} ->
              From ! {Ref, Notice};
          {{call, From}, _} ->
              gen_server:reply(From, Result)
      end,
  