anchor.diff:      Pid ! {self(), add, E}.
   
   main(Queue, Interval, Last) ->
  -    process_flag(trap_exit, true),
       case Queue of
   	[] ->
   	    Next = infinity;
  
positive.code: 	    receive
  		{Pid, add, E} ->
  		    Queue2 = Queue ++ [{Pid, E}],
  		    ?MODULE:main(Queue2, Interval, Last);
  		{'EXIT', From, Reason} ->
  		    io:format("timed_queue: Inflictor (~p) died with reason ~p, exiting~n", [From, Reason]),
  		    throw(inflictor_died);
  		Garbage ->
  		    io:format("timed_queue received garbage: ~p~n", [Garbage])
  	    after Next ->
  		    {Queue2, Last2} = shift_next(Queue, Last),
  		    ?MODULE:main(Queue2, Interval, Last2)
  
negative.code: test(TQ, I) ->
      receive
  	{elem, I2, N} ->
  	    io:format("<~p> received ~p ~p~n", [now_(), I2, N])
      after 100 ->
  	    case random:uniform(30) of
  		1 ->
  