Fetch config from keyword list

Config.ex

defmodule Config do

  def get(key, default) do
    # Sample config
    vars = [key1: :val1,
            key2: [nested_key1: :nested_val1,
                   nested_key2: :nested_val2]]

    get(key, vars, default)
  end

  def get(key) do

    # Sample config
    vars = [key1: :val1,
            key2: [nested_key1: :nested_val1,
                   nested_key2: :nested_val2]]

    get(key, vars, :undef)

  end

  defp get([head | tail], config, _) do

    remaining = get(head, config)
    get(tail, remaining)

  end

  defp get(key, config, default) do

    case is_list(config) do
      true ->
        case config do
          [] -> default
          _ ->
            case hd(config) do
              {^key, val} -> val
              _ -> get(key, tl(config))
            end
        end

      false -> config
    end

  end


end