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Re: What's so cool about Scheme?
At 04:47 PM 2003.06.03 -0500, Matt Hellige wrote:
> abstype prime = P of int
> val firstPrime = P 2
> fun nextPrime p = ...
> fun toInt (P n) = n
>What's wrong with this? Note that I definitely wouldn't call
>SML OO, but I argue that it does offer invariants...
Perhaps nothing is wrong with that; that *is* a 'poor man's object'. But all these languages lack, I think, a decent way to do inheritance / polymorphism with those objects. (<-- although at first appearance this seems to be a statement it is of course a challenge to show that you *can* :-)