anchor.diff:              Open =:= Required;
           _ ->
               false
  -    end.
  +    end.
positive.code:                                  internal_join(N, S)
                           end, State1, JoiningNodes),
  
      {reply, ok, State2#state{pending=Pending1}};
  
  handle_call({leave, Node}, From, State0) ->
      %% Perform leave.
  
negative.code:     DownFunctions = dict:append(Name, Function, DownFunctions0),
      {reply, ok, State#state{down_functions=DownFunctions}};
  
  handle_call({update_members, Nodes}, _From, #state{membership=Membership}=State) ->
      % lager:info("Updating membership with: ~p", [Nodes]),
  
      %% Get the current membership.
      CurrentMembership = [N || #{name := N} <- sets:to_list(?SET:query(Membership))],
      % lager:info("CurrentMembership: ~p", [CurrentMembership]),
  
      %% Compute leaving list.
      LeavingNodes = lists:filter(fun(N) ->
  