Question about None

[Paul Rubin]

Paul LaFollette <paul.lafollette at gmail.com> writes:
> So, what I would like is some sort of object that is a "kind of"
> everything but contains nothing, a unique minimal element of the
> partial ordering imposed on the set of classes by the inheritance
> heierarchy.  Whilst I am not naive mathematically, I am relatively
> naive in the area of language design.  In my naivete, it seemed to me
> that None could have been designed to be such a thing.  Apparently
> that is incorrect.

I don't remember if I linked to this article:

   http://en.wikibooks.org/wiki/Haskell/Denotational_semantics

You might like it.  If you want to learn some contemporary programming
language theory at a mathematical level, start with Harper's
"Practical Foundations for Programming Languages":

  http://www.cs.cmu.edu/~rwh/plbook/book.pdf