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1. mapMaybe :: (a -> Maybe b) -> NEIntMap a -> IntMap b

   nonempty-containers	Data.IntMap.NonEmpty

   O(n). Map values and collect the Just results. Returns a potentially empty map (IntMap), because the function could potentially return Nothing on all items in the NEIntMap.

   let f x = if x == "a" then Just "new a" else Nothing
   mapMaybe f (fromList ((5,"a") :| [(3,"b")])) == Data.IntMap.singleton 5 "new a"
   

2. mapMaybeWithKey :: (Key -> a -> Maybe b) -> NEIntMap a -> IntMap b

   nonempty-containers	Data.IntMap.NonEmpty

   O(n). Map keys/values and collect the Just results. Returns a potentially empty map (IntMap), because the function could potentially return Nothing on all items in the NEIntMap.

   let f k _ = if k < 5 then Just ("key : " ++ (show k)) else Nothing
   mapMaybeWithKey f (fromList ((5,"a") :| [(3,"b")])) == Data.IntMap.singleton 3 "key : 3"
   

3. mapMaybe :: (a -> Maybe b) -> NEMap k a -> Map k b

   nonempty-containers	Data.Map.NonEmpty

   O(n). Map values and collect the Just results. Returns a potentially empty map (Map), because the function could potentially return Nothing on all items in the NEMap.

   let f x = if x == "a" then Just "new a" else Nothing
   mapMaybe f (fromList ((5,"a") :| [(3,"b")])) == Data.Map.singleton 5 "new a"
   

4. mapMaybeWithKey :: (k -> a -> Maybe b) -> NEMap k a -> Map k b

   nonempty-containers	Data.Map.NonEmpty

   O(n). Map keys/values and collect the Just results. Returns a potentially empty map (Map), because the function could potentially return Nothing on all items in the NEMap.

   let f k _ = if k < 5 then Just ("key : " ++ (show k)) else Nothing
   mapMaybeWithKey f (fromList ((5,"a") :| [(3,"b")])) == Data.Map.singleton 3 "key : 3"
   

5. traverseMaybeWithKey :: Applicative t => (k -> a -> t (Maybe b)) -> NEMap k a -> t (Map k b)

   nonempty-containers	Data.Map.NonEmpty

   O(n). Traverse keys/values and collect the Just results. Returns a potentially empty map (Map), our function might return Nothing on every item in the NEMap. Use traverseMaybeWithKey1 whenever possible (if your Applicative also has Apply instance). This version is provided only for types that do not have Apply instance, since Apply is not at the moment (and might not ever be) an official superclass of Applicative.

6. traverseMaybeWithKey1 :: Apply t => (k -> a -> t (Maybe b)) -> NEMap k a -> t (Map k b)

   nonempty-containers	Data.Map.NonEmpty

   O(n). Traverse keys/values and collect the Just results. Returns a potentially empty map (Map), our function might return Nothing on every item in the NEMap. Is more general than traverseWithKey, since works with all Apply, and not just Applicative.

7. newtype ComposeMaybe (f :: k -> Type) (a :: k)

   patch	Data.Functor.Misc

   We can't use Compose Maybe instead of ComposeMaybe, because that would make the f parameter have a nominal type role. We need f to be representational so that we can use safe coerce.

8. ComposeMaybe :: Maybe (f a) -> ComposeMaybe (f :: k -> Type) (a :: k)

   patch	Data.Functor.Misc

   No documentation available.

9. getComposeMaybe :: ComposeMaybe (f :: k -> Type) (a :: k) -> Maybe (f a)

   patch	Data.Functor.Misc

   No documentation available.

10. catMaybes :: Vector (Maybe a) -> Vector a

    rebase	Rebase.Data.Vector

    No documentation available.

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