anchor.diff:      [begin
            {_, Pid} = lists:keyfind(Idx, 1, Pairs),
            MonRef = erlang:monitor(process, Pid),
  -         add_vnode_rec(#idxrec{key={Idx,Mod},idx=Idx,mod=Mod,pid=Pid,
  -                               monref=MonRef}, State),
  +         IdxRec = #idxrec{key={Idx,Mod},idx=Idx,mod=Mod,pid=Pid,
  +                          monref=MonRef},
  +         MonRec = #monrec{monref=MonRef, key={Idx,Mod}},
  +         add_vnode_rec([IdxRec, MonRec], State),
            Pid
        end || Idx <- IdxList].
   
  
positive.code: 
  %% @private
  delmon(MonRef, _State=#state{idxtab=T}) ->
      ets:match_delete(T, {idxrec, '_', '_', '_', '_', MonRef}).
  
  %% @private
  add_vnode_rec(I,  _State=#state{idxtab=T}) -> ets:insert(T,I).
  
negative.code:                           monref = Mref }
          end,
      IdxRecs = [F(Pid, Idx, Mod) || {Pid, {Mod, Idx}} <- PidIdxs],
      MonRecs = [#monrec{monref=Mref, key=Key}
                 || #idxrec{key=Key, monref=Mref} <- IdxRecs],
      true = ets:insert_new(IdxTable, IdxRecs ++ MonRecs),
      State#state{idxtab=IdxTable}.
  
  %% @private
  