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

   ghc-internal	GHC.Internal.Data.Maybe

   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]
   

2. mapM_ :: (Source r a, Index ix, Monad m) => (a -> m b) -> Array r ix a -> m ()

   massiv	Data.Massiv.Array

   Map a monadic function over an array sequentially, while discarding the result.

   Examples

   >>> import Data.Massiv.Array as A
   
   >>> rangeStepM Par (Ix1 10) 12 60 >>= A.mapM_ print
   10
   22
   34
   46
   58
   

3. mapMaybe :: (v1 -> Maybe v2) -> InsOrdHashMap k v1 -> InsOrdHashMap k v2

   openapi3	Data.HashMap.Strict.InsOrd.Compat

   No documentation available.

4. mapMaybeWithKey :: (k -> v1 -> Maybe v2) -> InsOrdHashMap k v1 -> InsOrdHashMap k v2

   openapi3	Data.HashMap.Strict.InsOrd.Compat

   No documentation available.

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

   protolude	Protolude

   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.

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

   protolude	Protolude

   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]
   

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

   reflex	Data.AppendMap

   Like mapMaybe but indicates whether the resulting container is empty

8. 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.

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

   reflex	Reflex.Class

   Like mapMaybe.

10. mapMixedAmount :: (Amount -> Amount) -> MixedAmount -> MixedAmount

    hledger-lib	Hledger.Data.Amount

    Apply a transform to a mixed amount's component Amounts.

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