defmodule Surgex.Parser.ContainParser do @moduledoc """ Checks if the given parameter's value is on the list of allowed values. """ @doc false def call(nil, _allowed_values), do: {:ok, nil} def call(input, allowed_values) when is_list(allowed_values) do case Enum.member?(allowed_values, input) do true -> {:ok, input} false -> {:error, :invalid_value} end end end