Re: [Haskell-cafe] Strange subtract operator behavior - and lazy naturals

On 10/19/07, Yitzchak Gale wrote:

So why not make the laziness available also for cases where "1 - 2 == 0" does _not_ do the right thing?

data LazyInteger = IntZero | IntSum Bool Integer LazyInteger

or

data LazyInteger = LazyInteger Bool Nat

I think data LazyInteger = IntDiff Nat Nat would admit implementation of most of the nice properties of this implementation. Comparison operators could short circuit when one of the two naturals is zero. The only value which would diverge when compared to a constant would be infinity - infinity. Luke