   end
 
   @doc """
-  Same as `tmp_dir` but raises `System.NoTmpDirError`
+  Writable temporary directory, exception on error.
+
+  Same as `tmp_dir/0` but raises `System.NoTmpDirError`
   instead of returning `nil` if no temp dir is set.
   """
   def tmp_dir! do

  end

  @doc """
  Returns the list of command-line arguments passed to the program.
  """
  @spec argv() :: [String.t]
  def argv do

  end

  @doc """
  Elixir version information.

  Returns Elixir's version as binary.
  """
  @spec version() :: String.t
  def version, do: get_version

  @doc """
  Elixir build information.

  Returns a keyword list with Elixir version, git tag info and compilation date.
  """
  @spec build_info() :: Keyword.t
  def build_info do
