On Sun, Jul 6, 2008 at 5:25 PM, John Hamilton wrote:

On Sun, Jul 6, 2008 at 16:45, Michael Feathers wrote:

...

segment :: Int -> [a] -> [[a]] segment 0 _ = [] segment _ [] = [] segment n x = (take n x) : segment n (drop n x)

I did a version of this which used splitAt but I wasn't sure whether it was going to buy me anything re performance that would justify its ugliness.

You can use

segment n = takeWhile (not . null) . unfoldr (Just . splitAt n)

I don't know how it compares in performance. It's from http://www.haskell.org/haskellwiki/Blow_your_mind

Watch out for negative numbers, though.