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1. mapMaybe :: (a -> Maybe b) -> Event a -> Event b

   reactive-midyim	Reactive.Banana.MIDI.Utility

   No documentation available.

2. mapM_ :: (Generator c, Monad m) => (Elem c -> m b) -> c -> m ()

   reducers	Data.Generator.Combinators

   Efficiently mapReduce a Generator using the Action monoid. A specialized version of its namesake from Data.Foldable and Control.Monad

   mapReduceWith getAction
   

3. mapMaybe :: forall (m :: Type -> Type) a b r . Monad m => (a -> Maybe b) -> Fold m b r -> Fold m a r

   streamly-core	Streamly.Data.Fold

   mapMaybe f fold maps a Maybe returning function f on the input of the fold, filters out Nothing elements, and return the values extracted from Just.

   >>> mapMaybe f = Fold.lmap f . Fold.catMaybes
   
   >>> mapMaybe f = Fold.mapMaybeM (return . f)
   

   >>> f x = if even x then Just x else Nothing
   
   >>> fld = Fold.mapMaybe f Fold.toList
   
   >>> Stream.fold fld (Stream.enumerateFromTo 1 10)
   [2,4,6,8,10]
   

4. mapMaybe :: forall (m :: Type -> Type) a b . Monad m => (a -> Maybe b) -> Stream m a -> Stream m b

   streamly-core	Streamly.Data.Stream

   Map a Maybe returning function to a stream, filter out the Nothing elements, and return a stream of values extracted from Just. Equivalent to:

   >>> mapMaybe f = Stream.catMaybes . fmap f
   

5. mapMaybeM :: Monad m => (a -> m (Maybe b)) -> Stream m a -> Stream m b

   streamly-core	Streamly.Data.Stream

   Like mapMaybe but maps a monadic function. Equivalent to:

   >>> mapMaybeM f = Stream.catMaybes . Stream.mapM f
   

   >>> mapM f = Stream.mapMaybeM (\x -> Just <$> f x)
   

6. mapMStep :: Applicative m => (a -> m b) -> Step s a -> m (Step s b)

   streamly-core	Streamly.Internal.Data.Fold

   Map a monadic function over the result b in Step s b. Internal

7. mapMaybe :: forall (m :: Type -> Type) a b r . Monad m => (a -> Maybe b) -> Fold m b r -> Fold m a r

   streamly-core	Streamly.Internal.Data.Fold

   mapMaybe f fold maps a Maybe returning function f on the input of the fold, filters out Nothing elements, and return the values extracted from Just.

   >>> mapMaybe f = Fold.lmap f . Fold.catMaybes
   
   >>> mapMaybe f = Fold.mapMaybeM (return . f)
   

   >>> f x = if even x then Just x else Nothing
   
   >>> fld = Fold.mapMaybe f Fold.toList
   
   >>> Stream.fold fld (Stream.enumerateFromTo 1 10)
   [2,4,6,8,10]
   

8. mapMaybeM :: Monad m => (a -> m (Maybe b)) -> Fold m b r -> Fold m a r

   streamly-core	Streamly.Internal.Data.Fold

   >>> mapMaybeM f = Fold.lmapM f . Fold.catMaybes
   

9. mapM_ :: Monad m => (a -> m b) -> Stream m a -> m ()

   streamly-core	Streamly.Internal.Data.Stream

   Execute a monadic action for each element of the Stream

10. mapMaybe :: forall (m :: Type -> Type) a b . Monad m => (a -> Maybe b) -> Stream m a -> Stream m b

    streamly-core	Streamly.Internal.Data.Stream

    Map a Maybe returning function to a stream, filter out the Nothing elements, and return a stream of values extracted from Just. Equivalent to:

    >>> mapMaybe f = Stream.catMaybes . fmap f
    

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