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module Maybe where
--
-- 1
--
isJust :: Maybe a -> Bool
isJust (Just _) = True
isJust Nothing = False
isNothing :: Maybe a -> Bool
isNothing (Just _) = False
isNothing Nothing = True
--
-- 2
--
mayybee :: b -> (a -> b) -> Maybe a -> b
mayybee v f Nothing = b
mayybee v f (Maybe x) = f x
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