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1. mapM_ :: Monad m => (a -> m b) -> Vector a -> m ()

   rio	RIO.Vector.Boxed

   No documentation available.

2. mapMaybe :: (a -> Maybe b) -> Vector a -> Vector b

   rio	RIO.Vector.Boxed

   No documentation available.

3. mapM_ :: (Monad m, Storable a) => (a -> m b) -> Vector a -> m ()

   rio	RIO.Vector.Storable

   No documentation available.

4. mapMaybe :: (Storable a, Storable b) => (a -> Maybe b) -> Vector a -> Vector b

   rio	RIO.Vector.Storable

   No documentation available.

5. mapM_ :: (Monad m, Unbox a) => (a -> m b) -> Vector a -> m ()

   rio	RIO.Vector.Unboxed

   No documentation available.

6. mapMaybe :: (Unbox a, Unbox b) => (a -> Maybe b) -> Vector a -> Vector b

   rio	RIO.Vector.Unboxed

   No documentation available.

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

   errors	Control.Error

   The mapMaybe function is a version of map which can throw out elements. In particular, the functional argument returns something of type Maybe b. If this is Nothing, no element is added on to the result list. If it is Just b, then b is included in the result list.

   Examples

   Using mapMaybe f x is a shortcut for catMaybes $ map f x in most cases:

   >>> import GHC.Internal.Text.Read ( readMaybe )
   
   >>> let readMaybeInt = readMaybe :: String -> Maybe Int
   
   >>> mapMaybe readMaybeInt ["1", "Foo", "3"]
   [1,3]
   
   >>> catMaybes $ map readMaybeInt ["1", "Foo", "3"]
   [1,3]
   

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

   >>> mapMaybe Just [1,2,3]
   [1,2,3]
   

8. mapMaybeT :: (m (Maybe a) -> n (Maybe b)) -> MaybeT m a -> MaybeT n b

   errors	Control.Error

   Transform the computation inside a MaybeT.

   • runMaybeT (mapMaybeT f m) = f (runMaybeT
     m)

9. mapM_ :: HashTable h => ((k, v) -> ST s b) -> h s k v -> ST s ()

   hashtables	Data.HashTable.Class

   A side-effecting map over the key-value records of a hash table. O(n).

10. mapM_ :: HashTable h => ((k, v) -> IO a) -> IOHashTable h k v -> IO ()

    hashtables	Data.HashTable.IO

    See the documentation for this function in mapM_.

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