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

   strict-base-types	Data.Maybe.Strict

   Analogous to mapMaybe in Data.Maybe.

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

   unboxing-vector	Data.Vector.Unboxing

   No documentation available.

3. mapMaybe :: Interval k e => (a -> Maybe b) -> IntervalMap k a -> IntervalMap k b

   IntervalMap	Data.IntervalMap.Generic.Lazy

   O(n). Map values and collect the Just results.

4. mapMaybe :: Interval k e => (a -> Maybe b) -> IntervalMap k a -> IntervalMap k b

   IntervalMap	Data.IntervalMap.Generic.Strict

   O(n). Map values and collect the Just results.

5. mapMaybe :: Interval k e => (a -> Maybe b) -> IntervalMap k a -> IntervalMap k b

   IntervalMap	Data.IntervalMap.Lazy

   O(n). Map values and collect the Just results.

6. mapMaybe :: Interval k e => (a -> Maybe b) -> IntervalMap k a -> IntervalMap k b

   IntervalMap	Data.IntervalMap.Strict

   O(n). Map values and collect the Just results.

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

   classy-prelude-yesod	ClassyPrelude.Yesod

   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. mapMaybe :: Fractional prob => (a -> Maybe b) -> T prob a -> T prob b

   probability	Numeric.Probability.Distribution

   No documentation available.

9. mapMaybe :: forall s k a b . (a -> Maybe b) -> HashMap s k a -> SomeHashMapWith (SupersetProof 'Hashed s) k b

   refined-containers	Data.HashMap.Refined

   Apply a function to all values in a map and collect only the Just results, returning a potentially smaller map.

10. mapMaybe :: forall s k a b . (a -> Maybe b) -> HashMap s k a -> SomeHashMapWith (SupersetProof 'Hashed s) k b

    refined-containers	Data.HashMap.Strict.Refined

    Apply a function to all values in a map and collect only the Just results, returning a potentially smaller map.

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