{-# LANGUAGE PatternSignatures #-}
module Main where

import Test.QuickCheck
import Test.QuickCheck.Function
import Test.QuickCheck.Poly

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prop_MapFilter (xs :: [A]) (Fun _ f) (Fun _ p) =
  filter p (map f xs) == map f (filter p xs)

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prop_Fold (Fun _ f) (xs :: [A]) =
  not (null xs) ==>
  foldl1 (curry f) xs == foldr1 (curry f) xs

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prop_Compose (x :: A) (Fun _ f) (Fun _ g) =
  f (g x) == g (f x)

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prop_String (Fun _ p) =
  p "some long string" ==> p "some other string"

----------------------------------------------------------------------------