Gregory Wright wrote:
-- A structure with internal state: -- data Tag s = Tag { tagID :: Int, state :: STRef s TagState, count :: STRef s Integer }
data FrozenTag = FrozenTag { ft_tagID :: Int, ft_state :: TagState, ft_count :: Integer } deriving Show
I would make all the fields strict here, to be sure that no lazyness can creep about unseen eg: data Tag s = Tag { tagID :: !Int, state :: !(STRef s TagState), count :: !(STRef s Integer) } -- ditto for FrozenTag (And use (writeSTRef ref $! value) as others have suggested) Regards, Brian. -- Logic empowers us and Love gives us purpose. Yet still phantoms restless for eras long past, congealed in the present in unthought forms, strive mightily unseen to destroy us. http://www.metamilk.com