-- | Displays a modified form of the second parameter before returning
-- it.
debugFn :: Show b => (a -> b) -> a -> a
debugFn fn x = debug (fn x) `seq` x
debugFn :: Show b => (a -> b) -> a -> a
debugFn fn x = debug (fn x) `seq` x
debugFn fn x = debug (fn x) `seq` x