Data.List.partition on infinite lists

I encountered that the implementation of 'partition' in GHC 6.2.1 fails on infinite lists:

partition :: (a -> Bool) -> [a] -> ([a],[a]) partition p xs = foldr (select p) ([],[]) xs

select p x (ts,fs) | p x = (x:ts,fs) | otherwise = (ts, x:fs)

With the following definition we don't have this problem:

partition :: (a -> Bool) -> [a] -> ([a], [a]) partition _ [] = ([],[]) partition p (x:xs) = let (y,z) = partition p xs in if p x then (x : y, z) else (y, x : z)

Prelude> take 10 $ fst $ partition even [0..] [0,2,4,6,8,10,12,14,16,18] Prelude> take 10 $ snd $ partition even [0..] [1,3,5,7,9,11,13,15,17,19]