math.ex

defmodule Math do

  def sum([]), do: 0
  def sum([head | tail]), do: head + sum(tail)

  def square([]), do: []
  def square([head | tail]), do: [head * head  | square(tail)]

end

ExUnit.start

defmodule MathTest do
  use ExUnit.Case

  test :sum_list_of_values_equal_to_8 do
    assert Math.sum([1,4,3]) == 8
  end

  test :sum_list_of_values_equal_to_6 do
    assert Math.sum([1,2,3]) == 6
  end

  test :square_list do
    assert Math.square([2,4,6]) == [4,16,36]
  end

end