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1. 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.

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

   reflex	Data.AppendMap

   Like mapMaybe but indicates whether the resulting container is empty

3. mapMapWithAdjustWithMove :: (Adjustable t m, Ord k) => (k -> v -> m v') -> Map k v -> Event t (PatchMapWithMove k v) -> m (Map k v', Event t (PatchMapWithMove k v'))

   reflex	Reflex.Adjustable.Class

   Traverses a Map, running the provided Adjustable action. The provided Event of patches to the Map can add, remove, update, move, or swap values.

4. mapMaybe :: Filterable f => (a -> Maybe b) -> f a -> f b

   reflex	Reflex.Class

   Like mapMaybe.

5. mapM_ :: (Monad m, FoldableLL full item) => (item -> m b) -> full -> m ()

   ListLike	Data.ListLike

   A map in monad space, discarding results.

6. mapM_ :: (Monad m, FoldableLL full item) => (item -> m b) -> full -> m ()

   ListLike	Data.ListLike.FoldableLL

   A map in monad space, discarding results.

7. mapM_ :: (Foldable t, Monad m) => (a -> m b) -> t a -> m ()

   basic-prelude	BasicPrelude

   Map each element of a structure to a monadic action, evaluate these actions from left to right, and ignore the results. For a version that doesn't ignore the results see mapM. mapM_ is just like traverse_, but specialised to monadic actions.

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

   basic-prelude	CorePrelude

   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]
   

9. mapMaybe :: (a -> Maybe b) -> IMap a -> IMap b

   brick	Data.IMap

   No documentation available.

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

    classy-prelude	ClassyPrelude

    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]
    

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