class FDB::DirectoryLayer

def remove_recursive(tr, node)
  subdir_names_and_nodes(tr, node).each do |name, subnode|
    remove_recursive(tr, subnode)
  end
  tr.clear_range_start_with(@node_subspace.unpack(node.key)[0])
  tr.clear_range(node.range[0], node.range[1])
end