Programming Elixir, Chapter 7.6, Exercise ListsAndRecursion-2

mylist.exs

defmodule MyList do

  def max([]), do: nil

  def max([head | []]), do: head

  def max([head | tail]) do
    _max(head, max(tail))
  end

  defp _max(a, b), do: (if a > b, do: a, else: b)
end