anchor.diff:      Suspected = sets:new(),
       Connections = dict:new(),
   
  +    %% Schedule periodic maintenance of the passive view.
  +    schedule_passive_view_maintenance(),
  +
       {ok, #state{pending=Pending,
                   active=Active,
                   passive=Passive,
  
positive.code:     Index = random:uniform(length(List)),
      lists:nth(Index, List).
  
  %% @doc Add to the active view.
  add_to_active_view({Name, _, _}=Peer, #state{active=Active0}=State0) ->
      lager:info("Adding ~p to active view on ~p", [Peer, myself()]),
  
negative.code: 
  %% @private
  -spec handle_info(term(), #state{}) -> {noreply, #state{}}.
  
  handle_info(passive_view_maintenance,
              #state{active=Active,
                     passive=Passive,
                     connections=Connections}=State) ->
  
      Exchange = %% Myself.
                 [myself()] ++
  
                 % Random members of the active list.
                 select_random_sublist(Active, k_active()) ++
  
                 %% Random members of the passive list.
                 select_random_sublist(Passive, k_passive()),
  
      %% Select random member of the active list.
      Random = select_random(Active),
  
      %% Forward shuffle request.
      do_send_message(Random,
                      {shuffle, Exchange, arwl(), myself()},
                      Connections),
  
      {noreply, State};
  
  handle_info({'EXIT', From, _Reason},
              #state{active=Active0,
  