packages feed

liquidhaskell-0.9.0.2.1: tests/neg/Monad6.hs

{-@ LIQUID "--expect-any-error" @-}
module Monad6 where

import Language.Haskell.Liquid.Prelude 

{-@ gpp :: Monad m => m {v:Int|v>=0} -> m {v:Int|v>0} @-}
gpp :: Monad m => m Int -> m Int
gpp z = do x <- z
           return $ liquidAssert (x >= 0) (x)