Re: [Haskell-cafe] Shouldnt this be lazy too?

Hi

...

Pretty much, yes.

So I just need to write

newtype LazyNatural = LazyNatural [()]

or data Nat = Zero | Succ Nat it's your choice really.

and then add some suitable instances. ;-)

Yes. Lots of them. Lots of instances and lots of methods.

Hey, the "length" function would then just be

ln_length :: [x] -> LazyNatural ln_length = LazyNatural . map (const ())

Ooo, that's hard.

Nope, its really easy. Its just quite a bit of work filling in all the instances. I bet you can't do it and upload the results to hackage within 24 hours :-) Thanks Neil