anchor.diff:              true = ets:insert(Table, {X, V1}),
               {reply, {ok, NextKey}, State#state{clock=Next}};
           true ->
  -            {reply, {ok, PrevNextKey}, State}
  +            {reply, {ok, NextKey0}, State}
     end;
   
   handle_command({is_det, Id}, _From, State = #state{table = Table}) ->
  
positive.code: handle_command({async_bind, Id, F, Arg}, _From,
                 State=#state{partition=Partition, table=Table}) ->
      [{_Key, V}] = ets:lookup(Table, Id),
      PrevNextKey = V#dv.next,
      if
          PrevNextKey == undefined ->
              Next = State#state.clock + 1,
              NextKey = {Next, Partition},
              declare(NextKey);
          true ->
              {Next, _} = PrevNextKey,
              NextKey = PrevNextKey
          end,
      spawn(derflow_vnode, execute_and_put, [F, Arg, NextKey, Id, Table]),
      {reply, {ok, NextKey}, State#state{clock=Next}};
  
negative.code: handle_command({next, X}, _From,
                 State = #state{partition = Partition, clock = Clock, table = Table}) ->
      [{_Key,V}] = ets:lookup(Table, X),
      NextKey0 = V#dv.next,
      if
          NextKey0 == undefined ->
              Next = Clock + 1,
              NextKey = {Next, Partition},
              declare(NextKey),
  