word_countv2.ex

defmodule Word do
  def count(string) do
    words = String.split(string, " ")

    words = words |> Enum.map(&String.trim/1) |> Enum.map(&String.downcase/1)

    words = Enum.filter(words, &(String.length(&1) > 1))

    word_counts =
      Enum.reduce(words, %{}, fn word, counts ->
        Map.update(counts, word, 1, &(&1 + 1))
      end)

    word_counts
  end
end

# Word.count("This is a test string") => %{"is" => 1, "string" => 1, "test" => 1, "this" => 1}