class Google::Cloud::Config

def add_options legacy_categories
  [legacy_categories].flatten(1).each do |sub_key|
    case sub_key
    when ::Symbol
      add_config! sub_key, Config.new
    when ::Hash
      sub_key.each do |k, v|
        add_config! k, Config.new(v)
      end
    else
      raise ArgumentError "Category must be a Symbol or Hash"
    end
  end
end