anchor.diff:  merge_mbr(Mbr1, Mbr2) ->
       {W1, S1, E1, N1} = Mbr1,
       {W2, S2, E2, N2} = Mbr2,
  -    {min(W1, W2), min(S1, S2), max(E1, E2), max(N1, N2)}.
  +    {erlang:min(W1, W2), erlang:min(S1, S2),
  +     erlang:max(E1, E2), erlang:max(N1, N2)}.
   
   
   find_area_min_nth([H|T]) ->
  
positive.code:         not IsDisjoint ->
              {W1, S1, E1, N1} = Mbr1,
              {W2, S2, E2, N2} = Mbr2,
              {max(W1, W2), max(S1, S2), min(E1, E2), min(N1, N2)};
          true ->
              {0, 0, 0, 0}
      end.
  
negative.code: pos_to_data(Fd, [H|T], DataList) ->
      {ok, Data} = couch_file:pread_term(Fd, H),
      pos_to_data(Fd, T, DataList ++ [Data]).
  