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1. scatMaybes :: Stream r ix (Maybe a) => Array r ix (Maybe a) -> Vector DS a

   massiv	Data.Massiv.Vector

   Keep all Maybes and discard the Nothings.

   Examples

2. simapMaybe :: Stream r ix a => (ix -> a -> Maybe b) -> Array r ix a -> Vector DS b

   massiv	Data.Massiv.Vector

   Similar to smapMaybe, but map with an index aware function.

   Examples

3. simapMaybeM :: forall r ix a b f . (Stream r ix a, Applicative f) => (ix -> a -> f (Maybe b)) -> Array r ix a -> f (Vector DS b)

   massiv	Data.Massiv.Vector

   Similar to smapMaybeM, but map with an index aware function.

   Examples

4. smapMaybe :: Stream r ix a => (a -> Maybe b) -> Array r ix a -> Vector DS b

   massiv	Data.Massiv.Vector

   Apply a function to each element of the array, while discarding Nothing and keeping the Maybe result.

   Examples

5. smapMaybeM :: forall r ix a b f . (Stream r ix a, Applicative f) => (a -> f (Maybe b)) -> Array r ix a -> f (Vector DS b)

   massiv	Data.Massiv.Vector

   Similar to smapMaybe, but with the Applicative function. Similar to mapMaybe id $ mapM f arr

   Examples

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

   openapi3	Data.HashMap.Strict.InsOrd.Compat

   No documentation available.

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

   openapi3	Data.HashMap.Strict.InsOrd.Compat

   No documentation available.

8. bitSizeMaybe :: Bits a => a -> Maybe Int

   protolude	Protolude

   Return the number of bits in the type of the argument. The actual value of the argument is ignored. Returns Nothing for types that do not have a fixed bitsize, like Integer.

9. catMaybes :: [Maybe a] -> [a]

   protolude	Protolude

   The catMaybes function takes a list of Maybes and returns a list of all the Just values.

   Examples

   Basic usage:

   >>> catMaybes [Just 1, Nothing, Just 3]
   [1,3]
   

   When constructing a list of Maybe values, catMaybes can be used to return all of the "success" results (if the list is the result of a map, then mapMaybe would be more appropriate):

   >>> import GHC.Internal.Text.Read ( readMaybe )
   
   >>> [readMaybe x :: Maybe Int | x <- ["1", "Foo", "3"] ]
   [Just 1,Nothing,Just 3]
   
   >>> catMaybes $ [readMaybe x :: Maybe Int | x <- ["1", "Foo", "3"] ]
   [1,3]
   

10. fromMaybe :: a -> Maybe a -> a

    protolude	Protolude

    The fromMaybe function takes a default value and a Maybe value. If the Maybe is Nothing, it returns the default value; otherwise, it returns the value contained in the Maybe.

    Examples

    Basic usage:

    >>> fromMaybe "" (Just "Hello, World!")
    "Hello, World!"
    

    >>> fromMaybe "" Nothing
    ""
    

    Read an integer from a string using readMaybe. If we fail to parse an integer, we want to return 0 by default:

    >>> import GHC.Internal.Text.Read ( readMaybe )
    
    >>> fromMaybe 0 (readMaybe "5")
    5
    
    >>> fromMaybe 0 (readMaybe "")
    0
    

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