[Haskell-cafe] Basic question concerning data constructors

ajb at spamcop.net ajb at spamcop.net
Wed Jan 2 06:15:02 EST 2008

G'day all.

Quoting Yitzchak Gale <gale at sefer.org>:

> Data types consist only of computable elements. Since there
> are only countably many computable functions, every data type
> has at most countably many elements. In particular, it is a set.

I still say it "isn't a set" in the same way that a group "isn't a set".
Haskell data types have structure that is respected by Haskell
homomorphisms.  Sets don't.

Andrew Bromage

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