anchor.diff:  init_per_round(Fun, Keys) when Fun =:= lindex;
                                  Fun =:= lrange_s;
                                  Fun =:= lrange_n;
  -                               Fun =:= lrem ->
  +                               Fun =:= lrem;
  +                               Fun =:= ltrim ->
     _ =
       edis_db:run(
         edis_db:process(0),
  
positive.code:     #edis_command{cmd = <<"LPUSHX">>, args = [?KEY, ?KEY],
                    group = lists, result_type = multi_bulk}).
  
  -spec lrange_s([binary()]) -> undefined.
  lrange_s([Key|_]) ->
    edis_db:run(
      edis_db:process(0),
  
negative.code:                   args = [?KEY, edis_util:binary_to_integer(Key), edis_util:binary_to_integer(Key)],
                    group = lists, result_type = multi_bulk}).
  
  -spec lrange_n([binary()]) -> [binary()].
  lrange_n([Key|_]) ->
    edis_db:run(
      edis_db:process(0),
  