Sums a lit of numbers in elixir

sum.ex

  @doc """
    iex>Misc.sum([1,1,1])
    3

    iex>Misc.sum([1, 2, 3, 4, 5])
    15
  """
  def sum(list) do 
    _sum(list, 0)
  end

  defp _sum([], total) do 
    total
  end

  defp _sum([head | tail], total) do
    _sum(tail, head + total)
  end