anchor.diff:                         #edis_item{key = Key, encoding = raw,
                                     type = string, value = Value})} || {Key, Value} <- KVs],
                       []),
  -  {reply, Reply, State};
  +  {reply, Reply, stamp([K || {K, _} <- KVs], State)};
   handle_call({set_nx, KVs}, _From, State) ->
  -  case lists:any(
  -         fun({Key, _}) ->
  -                 exists_item(State#state.db, Key)
  -         end, KVs) of
  -    true ->
  -      {reply, {error, already_exists}, State};
  -    false ->
  -      Reply =
  +  Reply =
  +    case lists:any(
  +           fun({Key, _}) ->
  +                   exists_item(State#state.db, Key)
  +           end, KVs) of
  +      true ->
  +        {reply, {error, already_exists}, State};
  +      false ->
           eleveldb:write(State#state.db,
                          [{put, Key,
                            erlang:term_to_binary(
                              #edis_item{key = Key, encoding = raw,
                                         type = string, value = Value})} || {Key, Value} <- KVs],
  -                       []),
  -      {reply, Reply, State}
  -  end;
  +                       [])
  +    end,
  +  {reply, Reply, stamp([K || {K, _} <- KVs], State)};
   handle_call({set_bit, Key, Offset, Bit}, _From, State) ->
     Reply =
       update(State#state.db, Key, string, raw,
  
positive.code: 
  -include("edis.hrl").
  -define(DEFAULT_TIMEOUT, 5000).
  -define(ACCESS_DUMP_INTERVAL, 10000).
  
  -type item_type() :: string | hash | list | set | zset.
  -type item_encoding() :: raw | int | ziplist | linkedlist | intset | hashtable | zipmap | skiplist.
  
negative.code:                        throw(bad_item_type)
                     end
             end, <<"0">>),
    {reply, Reply, stamp(Key, State)};
  handle_call({set, KVs}, _From, State) ->
    Reply =
      eleveldb:write(State#state.db,
  