pop.ex

# Ok, so popping an immutable list is like cutting off the head of a hydra:
# it doesn't really get rid of the head :) See -> Enum.take/2.
defmodule ListUtils do
  def pop(list, n, acc \\ [])
  def pop([], _n, acc), do: Enum.reverse(acc)
  def pop(_list, 0, acc), do: Enum.reverse(acc)

  def pop([head | tail], n, acc) do
    pop(tail, n - 1, [head | acc])
  end
end

[1,2,3,4,5] |> ListUtils.pop(3) |> IO.inspect #=> [1,2,3]