deptup1.hs

module Deptup () where

import Language.Haskell.Liquid.Prelude

{-@ data Pair a b <p :: x0:a -> x1:b -> Bool> = P {pX :: a, pY :: b<p pX> } @-}
data Pair a b = P a b

incr        :: Int -> Int
incr x      = x + 1

baz x       = P x (incr x)

bazList xs  = map baz xs

n           = choose 0
xs          = [0..n]

chk (P x y) = liquidAssertB (x < y)
prop_baz    = map chk $ bazList xs