Yes, what you are looking at here is a code sample of what is possible
with Jackbox closures. You see normally decorators in ruby either suffer
from class identity loss or limit the times they can be applied to an
object to 1(one) time.
Here a a couple of articles on that:
So with our closures you can apply the same pattern to an object over
and over,
cup = Coffee.new.enrich milk, sprinkles, sprinkles
but the instance remains being what it is.
cup.should be_instance_of(Coffee)
What's more you can have the class introspect on the decorators it
possesses.