anchor.diff:  -define(TRACE_SEND(Pid, Msg), ?TRACE("[ ~.0p ] to ~.0p: ~.0p~n", [self(), Pid, Msg])).
   -define(TRACE1(Msg, State),
           ?TRACE("[ ~.0p ]~n  Msg: ~.0p~n  State: ~.0p~n", [self(), Msg, State])).
  -%% -define(TRACE_STATE(OldState, NewState),
  +%% -define(TRACE_STATE(OldState, NewState, Reason),
   %%         case element(1, OldState) =/= element(1, NewState) of
  -%%             true -> log:pal("[ ~.0p ]~n  new Neighbors: ~.0p~n",
  -%%                [self(), nodelist:to_list(get_neighbors(NewState))]);
  +%%             true -> log:pal("[ ~.0p ] ~p~n  new Neighbors: ~.0p~n",
  +%%                [self(), Reason, nodelist:to_list(get_neighbors(NewState))]);
   %%             _    -> ok
   %%         end).
  --define(TRACE_STATE(OldState, NewState), ok).
  +-define(TRACE_STATE(OldState, NewState, Reason), ok).
   
   -export([send_trigger/0, init_first/0, init/4, on/2,
            leave/0, update_id/1,
  
positive.code:     RM_State = ?RM:init(Me, Pred, Succ),
      set_failuredetector(?RM:get_neighbors(RM_State)),
      NewState = {RM_State, false, SubscrTable},
      ?TRACE_STATE({null, null, null}, NewState),
      NewState.
  
  %% @doc Creates a state() object for a unit test.
  
negative.code:     call_subscribers(OldNeighborhood, NewNeighborhood, Reason, SubscrTable),
      update_failuredetector(OldNeighborhood, NewNeighborhood, CrashedPid),
      NewState = {NewRM_State, HasLeft, SubscrTable},
      ?TRACE_STATE(_OldState, NewState, Reason),
      NewState.
  
  % @doc Subscribe all PIDs in the neighborhood with the failuredetector.
  