On Monday 04 October 2010 20:19:39, Daniel Fischer wrote:
Yes, they are fragile. However, since (to my surprise) uncurry isn't available in Data.List, I've tried with a special function for uncurry (:),
cons :: (a,[a]) -> [a] cons (x,xs) = x : xs
vlines :: String -> [String] vlines "" = [] vlines s = cons $ case break (== '\n') s of (l, s') -> (l, case s' of [] -> [] _:s'' -> vlines s'')
, which gives slightly less fragile looking Core (
--the second argument of (:) doesn't contain a reference to the first anymore).
Arrgh. And that is again as strict as the naked case, cons needs a lazy pattern, which means it gets the same core as uncurry (:). Still, it doesn't leak on current GHCs, so for the time being, it's a fix (not on JHC though, that leaks with all implementations I tried). If anybody can offer a more stable fix of the leak, I'd be happy.