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

On Thu, Jun 21, 2012 at 5:36 PM, Richard O'Keefe wrote: It always struck me as odd that Enum doesn't extend Ord.

There's a reason given for not having Bounded extend Ord, which doesn't really apply to a class having fromEnum :: a -> Int. Testing whether an enum bound is at a limit is thus a bit tricky.

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