   end
 
   @doc """
-  Get current value of the option `name`. Raises ArgumentError if name is not a
+  Get current value of the option `name`. Raises `ArgumentError` if `name` is not a
   known option.
   """
   def get(name)

  end

  @doc """
  Returns a string with the option's description. Raises if `name` is not a
  known option.
  """
  def help(name) do
    if name in @supported_options do

  @doc """
  Sets the value for the option `name` to `value`.

  Returns the option's previous value in the case of success.

  If `name` is not a known option or if `value` is invalid, raises
  `ArgumentError`.
  """
  def set(name, value)

