Re: [Haskell-cafe] Why does Enum succ and pred functions throw exception

An ordering does not typically induce a computable enumeration. For example, there are infinitely many rationals between any pair of rationals.

I didn't say it was odd that Ords weren't Enums, I said that it's odd that Enums aren't Ords. It makes little or no sense to make treat rationals as Enums; the intent of enums is generally to provide *exhaustive* enumeration of a *discrete* set.