Extract Hash params from the array if the last element is a Hash

extract_params.rb

class Array

  ## Extract Hash params from the array with defaults if the last element is
  # a Hash (otherwise returns defaults as is). To be used with *args, e.g.
  #
  # def function *args
  #   params = args.extract_params! { :defval => 'foobar' }
  #   ...
  # end
  def extract_params! defaults = {}
    if (dict=last).is_a?(Hash)
      defaults.update dict
      pop
    end
    defaults
  end
end