[Haskell-cafe] Code Golf

[Sebastian Fischer]

> ghci> let diag = foldr (curry (prod mappend fst snd . uncurry  
> (coprod mappend (splitAt 2) (splitAt 1)))) []

nice :)

thanks to the comments of Martijn and Jan we can replace prod and  
coprod by liftA2 and <fancy dots>:

 > let diag = foldr (curry (liftA2 mappend fst snd.uncurry (((flip.). 
(((.).).).(.)) mappend (splitAt 2) (splitAt 1)))) []

It works for the finite tests but, unfortunately, not for the infinite  
one :(

 > take 10 $ diag [[ (m,n) | n <- [1..]] | m <- [1..]]
*** Exception: stack overflow