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module Or where
import Data.Semigroup
import Test.QuickCheck
data Or a b =
Fst a
| Snd b
deriving (Eq, Show)
instance Semigroup (Or a b) where
(Snd x) <> _ = Snd x
_ <> x = x
instance (Arbitrary a, Arbitrary b) => Arbitrary (Or a b) where
arbitrary = do
x <- arbitrary
y <- arbitrary
frequency [ (1, return $ Fst x), (1, return $ Snd y) ]
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