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mapMaybe :: forall (m :: Type -> Type) a b . Monad m => (a -> Maybe b) -> Stream m a -> Stream m bstreamly-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
mapMaybeM :: Monad m => (a -> m (Maybe b)) -> Stream m a -> Stream m bstreamly-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 <$> f x)
mapMStep :: Applicative m => (a -> m b) -> Step s a -> m (Step s b)streamly-core Streamly.Internal.Data.Fold Map a monadic function over the result b in Step s b. Internal
mapMaybe :: forall (m :: Type -> Type) a b r . Monad m => (a -> Maybe b) -> Fold m b r -> Fold m a rstreamly-core Streamly.Internal.Data.Fold mapMaybe f fold maps a Maybe returning function f on the input of the fold, filters out Nothing elements, and return the values extracted from Just.
>>> mapMaybe f = Fold.lmap f . Fold.catMaybes >>> mapMaybe f = Fold.mapMaybeM (return . f)
>>> f x = if even x then Just x else Nothing >>> fld = Fold.mapMaybe f Fold.toList >>> Stream.fold fld (Stream.enumerateFromTo 1 10) [2,4,6,8,10]
mapMaybeM :: Monad m => (a -> m (Maybe b)) -> Fold m b r -> Fold m a rstreamly-core Streamly.Internal.Data.Fold >>> mapMaybeM f = Fold.lmapM f . Fold.catMaybes
mapM_ :: Monad m => (a -> m b) -> Stream m a -> m ()streamly-core Streamly.Internal.Data.Stream Execute a monadic action for each element of the Stream
mapMaybe :: forall (m :: Type -> Type) a b . Monad m => (a -> Maybe b) -> Stream m a -> Stream m bstreamly-core Streamly.Internal.Data.Stream Map a Maybe returning function to a stream, filter out the Nothing elements, and return a stream of values extracted from Just. Equivalent to:
>>> mapMaybe f = Stream.catMaybes . fmap f
mapMaybeM :: Monad m => (a -> m (Maybe b)) -> Stream m a -> Stream m bstreamly-core Streamly.Internal.Data.Stream Like mapMaybe but maps a monadic function. Equivalent to:
>>> mapMaybeM f = Stream.catMaybes . Stream.mapM f
>>> mapM f = Stream.mapMaybeM (\x -> Just <$> f x)
mapMSerial :: Monad m => (a -> m b) -> StreamK m a -> StreamK m bstreamly-core Streamly.Internal.Data.StreamK No documentation available.
mapMWith :: (m b -> StreamK m b -> StreamK m b) -> (a -> m b) -> StreamK m a -> StreamK m bstreamly-core Streamly.Internal.Data.StreamK No documentation available.