anchor.diff:                        Acc
                 end,
       lists:reverse(eleveldb_fold(T, FirstKey, EndKey, FoldFun, [])).
  -
   
   %% @doc Updates all chunk info, by deleting existing entries if exists
   %% and putting new chunk info
  
positive.code:     DeleteOps = lists:map(fun({O, L, _}) ->
                                    {delete, sext:encode({O, L})}
                            end, Chunks),
      eleveldb:write(T, DeleteOps ++ PutOps, [{sync, true}]).
  
  -spec find_leftneighbor(table(), non_neg_integer()) ->
  
negative.code:     {ok, I} = eleveldb:iterator(T, [], keys_only),
      EndKey = sext:encode({Offset+Size, 0}),
      StartKey = sext:encode({Offset, Size}),
      {ok, FirstKey} = case eleveldb:iterator_move(I, StartKey) of
                           {error, invalid_iterator} ->
                               try
                                   %% Assume that the invalid_iterator is because
                                   %% we tried to move to the end via StartKey.
                                   %% Instead, move there directly.
                                   {ok, _} = eleveldb:iterator_move(I, last),
                                   {ok, _} = eleveldb:iterator_move(I, prev)
                               catch
                                   _:_ ->
                                       {ok, _} = eleveldb:iterator_move(I, first)
                               end;
                           {ok, _} = R0 ->
                               case eleveldb:iterator_move(I, prev) of
                                   {error, invalid_iterator} ->
  