anchor.diff:  %% @todo Remove me.
   -compile([export_all]).
   
  +-define(PASSIVE_VIEW_MAINTENANCE_INTERVAL, 10000).
   -define(ACTIVE_SIZE, 5).
   -define(PASSIVE_SIZE, 30).
   -define(ARWL, 6).
  
positive.code:     Suspected = sets:new(),
      Connections = dict:new(),
  
      {ok, #state{pending=Pending,
                  active=Active,
                  passive=Passive,
  
negative.code:             State0
      end,
      {reply, ok, State};
  
  handle_message({shuffle_reply, Exchange, _Sender}, State0) ->
      State = merge_exchange(Exchange, State0),
      {noreply, State};
  
  handle_message({shuffle, Exchange, TTL, Sender},
                 #state{active=Active0,
                        passive=Passive0,
                        connections=Connections}=State0) ->
      %% Forward to random member of the active view.
      State = case TTL > 0 andalso sets:size(Active0) > 1 of
          true ->
              Random = select_random(Active0, Sender),
  
              %% Forward shuffle until random walk complete.
              do_send_message(Random,
                              {shuffle, Exchange, TTL - 1, myself()},
                              Connections),
  
              State0;
          false ->
              %% Randomly select nodes from the passive view and respond.
              ResponseExchange = select_random_sublist(Passive0,
                                                       length(Exchange)),
  
              do_send_message(Sender,
                              {shuffle_reply, ResponseExchange, myself()},
                              Connections),
  
              merge_exchange(Exchange, State0)
      end,
      {noreply, State};
  
  handle_message({forward_join, Peer, TTL, Sender},
                 #state{active=Active0,
  