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1. partitionMaybe :: (a -> Maybe b) -> [a] -> ([b], [a])

   utility-ht	Data.List.HT

   Partition a list into elements which evaluate to Just or Nothing by f.

   forAllMaybeFn $ \f xs -> partitionMaybe f xs == (mapMaybe f xs, filter (isNothing . f) xs)
   

   forAllPredicates $ \p xs -> partition p xs == partitionMaybe (\x -> toMaybe (p x) x) xs
   

2. segmentAfterMaybe :: (a -> Maybe b) -> [a] -> ([([a], b)], [a])

   utility-ht	Data.List.HT

   Deprecated: use segmentAfterJust instead

3. segmentBeforeMaybe :: (a -> Maybe b) -> [a] -> ([a], [(b, [a])])

   utility-ht	Data.List.HT

   Deprecated: use segmentBeforeJust instead

4. toMaybe :: Bool -> a -> Maybe a

   utility-ht	Data.Maybe.HT

   Returns Just if the precondition is fulfilled. prop> b x -> (guard b >> x) == (toMaybe b =<< (x::Maybe Char))

5. mapMaybe :: forall (m :: Type -> Type) a b . Functor m => (a -> Maybe b) -> SourceT m a -> SourceT m b

   servant	Servant.Types.SourceT

   Filter values.

   >>> toList $ mapMaybe (\x -> if odd x then Just x else Nothing) (source [0..10]) :: [Int]
   [1,3,5,7,9]
   

   >>> mapMaybe (\x -> if odd x then Just x else Nothing) (source [0..2]) :: SourceT Identity Int
   fromStepT (Effect (Identity (Skip (Yield 1 (Skip Stop)))))
   

   Illustrates why we need Skip.

6. mapMaybeStep :: forall (m :: Type -> Type) a b . Functor m => (a -> Maybe b) -> StepT m a -> StepT m b

   servant	Servant.Types.SourceT

   No documentation available.

7. parseMaybe :: (a -> Parser b) -> a -> Maybe b

   yaml	Data.Yaml

   Run a Parser with a Maybe result type.

8. genMaybe :: Gen a -> Gen (Maybe a)

   genvalidity	Data.GenValidity.Utils

   No documentation available.

9. shrinkMaybe :: (a -> [a]) -> Maybe a -> [Maybe a]

   genvalidity	Data.GenValidity.Utils

   Lift a shrinker function into a maybe

10. flagToMaybe :: Flag a -> Maybe a

    Cabal	Distribution.Simple.Flag

    Converts a Flag value to a Maybe value.

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