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1. mapMaybeM :: Monad m => (a -> m (Maybe b)) -> Stream (Of a) m r -> Stream (Of b) m r

   streaming	Streaming.Prelude

   Map monadically over a stream, producing a new stream only containing the Just values.

2. mapMaybeWithKey :: Enum k => (k -> a -> Maybe b) -> EnumMap k a -> EnumMap k b

   enummapset	Data.EnumMap.Lazy

   No documentation available.

3. mapMaybeWithKey :: Enum k => (k -> a -> Maybe b) -> EnumMap k a -> EnumMap k b

   enummapset	Data.EnumMap.Strict

   No documentation available.

4. mapMaybeWithKey :: (forall (tp :: v) . () => k tp -> f tp -> Maybe (g tp)) -> MapF k f -> MapF k g

   parameterized-utils	Data.Parameterized.Map

   Map keys and elements and collect Just results.

5. mapMaybeNoNull :: (a -> Maybe b) -> MonoidalMap token a -> Maybe (MonoidalMap token b)

   reflex	Data.AppendMap

   Like mapMaybe but indicates whether the resulting container is empty

6. mapMaybeDTyConEnv :: (a -> Maybe b) -> DTyConEnv a -> DTyConEnv b

   ghc-lib-parser	GHC.Core.TyCon.Env

   No documentation available.

7. mapMaybeBag :: (a -> Maybe b) -> Bag a -> Bag b

   ghc-lib-parser	GHC.Data.Bag

   No documentation available.

8. mapMaybeBagM :: Monad m => (a -> m (Maybe b)) -> Bag a -> m (Bag b)

   ghc-lib-parser	GHC.Data.Bag

   No documentation available.

9. mapMaybeFsEnv :: (elt1 -> Maybe elt2) -> FastStringEnv elt1 -> FastStringEnv elt2

   ghc-lib-parser	GHC.Data.FastString.Env

   No documentation available.

10. mapMaybeMissing :: forall (f :: Type -> Type) x y . Applicative f => (Key -> x -> Maybe y) -> WhenMissing f x y

    ghc-lib-parser	GHC.Data.Word64Map.Internal

    Map over the entries whose keys are missing from the other map, optionally removing some. This is the most powerful SimpleWhenMissing tactic, but others are usually more efficient.

    mapMaybeMissing :: (Key -> x -> Maybe y) -> SimpleWhenMissing x y
    

    mapMaybeMissing f = traverseMaybeMissing (\k x -> pure (f k x))
    

    but mapMaybeMissing uses fewer unnecessary Applicative operations.

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