Elixir HW1 - February 9, 2021

HW1.ex

require Integer

defmodule HW1 do

  def custom_sum(a, b) when is_number(a) and is_number(b), do: {:ok, round(a) + round(b)}
  def custom_sum(_, _), do: {:error, :badarg}

  def even_length([]), do {:error, :must_be_even}
  def even_length(a) when is_list(a) do

    a_length = length(a)

    cond do
      Integer.is_even(a_length) -> {:ok, a_length}
      true -> {:error, :must_be_even}
    end
  end
end