Alexander Dunlap wrote:
You might also look at Control.Monad.filterM. I often define a function "partitionM" which is like partition except it uses a monadic test, just like you have.
Just for completeness, my partitionM: partitionM :: (Monad m) => (a -> m Bool) -> [a] -> m ([a], [a]) partitionM _ [] = return ([], []) partitionM p (x:xs) = do flg <- p x (ys, ns) <- partitionM p xs return (if flg then (x:ys, ns) else (ys, x:ns)) Cheers, Erik -- ----------------------------------------------------------------- Erik de Castro Lopo ----------------------------------------------------------------- "Indeed, I am impressed that Google runs an 8,000 node Linux cluster, 5 data centers, an extensive network, and a rapidly evolving application all with a staff of 12." -- http://research.microsoft.com/~gray/papers/FAAMs_HPTS.doc