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1. mapMaybe :: forall b a . (a -> Maybe b) -> Slist a -> Slist b

   slist	Slist.Maybe

   The Maybe version of map which can throw out elements. If appliying the given function returns Nothing, no element is added on to the result list. If it is Just b, then b is included in the result list.

   >>> maybeEven x = if even x then Just x else Nothing
   
   >>> s = cons 1 $ cons 2 $ one 3
   

   >>> mapMaybe maybeEven s
   Slist {sList = [2], sSize = Size 1}
   

   If we map the Just constructor, the entire list should be returned:

   >>> mapMaybe Just s
   Slist {sList = [1,2,3], sSize = Size 3}
   

2. mapM_ :: Monad m => (a -> m b) -> SerialT m a -> m ()

   streamly	Streamly.Internal.Data.Stream.IsStream

   mapM_ = Stream.drain . Stream.mapM
   

   Apply a monadic action to each element of the stream and discard the output of the action. This is not really a pure transformation operation but a transformation followed by fold.

3. mapMaybe :: forall t (m :: Type -> Type) a b . (IsStream t, Monad m) => (a -> Maybe b) -> t m a -> t m b

   streamly	Streamly.Internal.Data.Stream.IsStream

   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.map fromJust . Stream.filter isJust . Stream.map f
   

4. mapMaybeM :: (IsStream t, MonadAsync m, Functor (t m)) => (a -> m (Maybe b)) -> t m a -> t m b

   streamly	Streamly.Internal.Data.Stream.IsStream

   Like mapMaybe but maps a monadic function. Equivalent to:

   mapMaybeM f = Stream.map fromJust . Stream.filter isJust . Stream.mapM f
   

   Concurrent (do not use with fromParallel on infinite streams)

5. mapM_ :: Monad m => (a -> m b) -> SerialT m a -> m ()

   streamly	Streamly.Prelude

   mapM_ = Stream.drain . Stream.mapM
   

   Apply a monadic action to each element of the stream and discard the output of the action. This is not really a pure transformation operation but a transformation followed by fold.

6. mapMaybe :: forall t (m :: Type -> Type) a b . (IsStream t, Monad m) => (a -> Maybe b) -> t m a -> t m b

   streamly	Streamly.Prelude

   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.map fromJust . Stream.filter isJust . Stream.map f
   

7. mapMaybeM :: (IsStream t, MonadAsync m, Functor (t m)) => (a -> m (Maybe b)) -> t m a -> t m b

   streamly	Streamly.Prelude

   Like mapMaybe but maps a monadic function. Equivalent to:

   mapMaybeM f = Stream.map fromJust . Stream.filter isJust . Stream.mapM f
   

   Concurrent (do not use with fromParallel on infinite streams)

8. mapMaybe :: (a -> Maybe b) -> [a] -> [b]

   strict-base-types	Data.Maybe.Strict

   Analogous to mapMaybe in Data.Maybe.

9. mapM_ :: (Monad m, Unboxable a) => (a -> m b) -> Vector a -> m ()

   unboxing-vector	Data.Vector.Unboxing

   No documentation available.

10. mapMaybe :: (Unboxable a, Unboxable b) => (a -> Maybe b) -> Vector a -> Vector b

    unboxing-vector	Data.Vector.Unboxing

    No documentation available.

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