Interesting idea.
One approach would be to test against the _environment_ of the prototype
object in the class definition. Since the initialize method for a
reference class must call new.env(), one knows that a real object from
the class has a different environment. Using that fact one could
Dear John and others,
I've been wondering about whether there's any way to indicate a "nil"
reference class object, which will represent "no value", and be tested
for, but not fail the internal type checking. NULL is the obvious
choice (or seems so to me), but can only be used if an explicit class
