Hiding class pointers -- was it a good idea?

[Walter Bright]

Robert Fraser wrote:
> Making something part of the language
> standardizes it. That's why having unittests, asserts, preconditions,
> etc., in D is such a boon: while that could all be done using a
> library, there'd probably be three or four different libraries out
> there to do it and 75% of users wouldn't know about them or use those
> features at all.

Right on.