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1. productMaybeWith :: (a -> b -> Maybe c) -> [[a]] -> [[b]] -> [[c]]

   leancheck	Test.LeanCheck

   Take the product of lists of tiers by a function returning a Maybe value discarding Nothing values.

2. productMaybeWith :: (a -> b -> Maybe c) -> [[a]] -> [[b]] -> [[c]]

   leancheck	Test.LeanCheck.Error

   Take the product of lists of tiers by a function returning a Maybe value discarding Nothing values.

3. funToListMaybe :: Listable a => (a -> b) -> [Maybe b]

   leancheck	Test.LeanCheck.Function.List

   Converts a function to a list of Just result values or Nothing on error.

   > take 6 $ funToListMaybe $ head :: [Maybe Int]
   [Nothing,Just 0,Just 0,Just 1,Just 0,Just 0]
   

   This uses errorToNothing and consequently unsafePerformIO.

4. catMaybesT :: [[Maybe a]] -> [[a]]

   leancheck	Test.LeanCheck.Tiers

   Concatenate tiers of maybes

5. mapMaybeT :: (a -> Maybe b) -> [[a]] -> [[b]]

   leancheck	Test.LeanCheck.Tiers

   Like mapMaybe but for tiers.

6. productMaybeWith :: (a -> b -> Maybe c) -> [[a]] -> [[b]] -> [[c]]

   leancheck	Test.LeanCheck.Tiers

   Take the product of lists of tiers by a function returning a Maybe value discarding Nothing values.

7. mapMaybeMProp :: (IsList c, IsList d, Eq d, Show d, Show b, Item c ~ a, Item d ~ b, Arbitrary c, Arbitrary b, Show c, Show a, CoArbitrary a, Function a) => Proxy a -> Proxy b -> (forall s . () => (a -> ST s (Maybe b)) -> c -> ST s d) -> Property

   quickcheck-classes-base	Test.QuickCheck.Classes.Base.IsList

   No documentation available.

8. mapMaybeProp :: (IsList c, Item c ~ a, Item d ~ b, Eq d, IsList d, Arbitrary b, Show d, Show b, Arbitrary c, Show c, Show a, Eq c, CoArbitrary a, Function a) => Proxy a -> Proxy b -> ((a -> Maybe b) -> c -> d) -> Property

   quickcheck-classes-base	Test.QuickCheck.Classes.Base.IsList

   Property for the mapMaybe function, which keeps elements for which the predicate holds true.

9. fromMaybeS :: Selective f => f a -> f (Maybe a) -> f a

   selective	Control.Selective

   A lifted version of fromMaybe.

10. greadMaybe :: GRead t => String -> (forall (a :: k) . () => t a -> b) -> Maybe b

    some	Data.GADT.Show

    >>> greadMaybe "InL Refl" mkSome :: Maybe (Some (Sum ((:~:) Int) ((:~:) Bool)))
    Just (mkSome (InL Refl))
    

    >>> greadMaybe "L1 Refl" mkSome :: Maybe (Some ((:~:) Int :+: (:~:) Bool))
    Just (mkSome (L1 Refl))
    

    >>> greadMaybe "garbage" mkSome :: Maybe (Some ((:~:) Int))
    Nothing
    

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