   def delete(%HashSet{root: root, size: size} = set, term) do
     case do_delete(root, term, key_hash(term)) do
       {:ok, root} -> %HashSet{root: root, size: size - 1}
-      :error      -> set
+      :error -> set
     end
   end
 


  defp do_member?(node, term, hash) do
    index = key_mask(hash)
    case elem(node, index) do
      []          -> false
      [^term | _] -> true
      [_]         -> false
      [_ | n]     -> do_member?(n, term, key_shift(hash))
    end
  end

  defp do_put(node, term, hash) do
    index = key_mask(hash)
    case elem(node, index) do
      [] ->
        {put_elem(node, index, [term]), 1}
      [^term | _] ->
        {node, 0}
      [t] ->
        n = put_elem(@node_template, key_mask(key_shift(hash)), [term])
        {put_elem(node, index, [t | n]), 1}
      [t | n] ->
        {n, counter} = do_put(n, term, key_shift(hash))
        {put_elem(node, index, [t | n]), counter}

  def inspect(set, opts) do
    # Avoid warnings about HashSet being deprecated.
    module = HashSet
    concat(["#HashSet<", Inspect.List.inspect(module.to_list(set), opts), ">"])
  end
end
