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:     State#state{pending=Pending, connections=Connections}.
  
  sync_internal_join(#{name := Name} = Node,
                From,      
                #state{pending=Pending0,
                       sync_joins=SyncJoins0,
                       connections=Connections0,
  