module Foo () where import Language.Haskell.Liquid.Prelude -- gpp :: Monad m => m Int -> m Int gpp z = do x <- z return $ liquidAssert (x > 0) (x - 10) incrlist n = n : incrlist (n+1) xs, ys, zs :: Maybe Int xs = Just 9 ys = gpp xs zs = gpp ys