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1. mapMonotonic :: (a -> b) -> Set a -> Set b

   rio	RIO.Set.Unchecked

   The mapMonotonic f s == map f s, but works only when f is strictly increasing. The precondition is not checked. Semi-formally, we have:

   and [x < y ==> f x < f y | x <- ls, y <- ls]
   ==> mapMonotonic f s == map f s
   where ls = toList s
   

2. mapM_ :: (Monad m, Vector v a) => (a -> m b) -> v a -> m ()

   rio	RIO.Vector

   No documentation available.

3. mapMaybe :: (Vector v a, Vector v b) => (a -> Maybe b) -> v a -> v b

   rio	RIO.Vector

   No documentation available.

4. mapM_ :: Monad m => (a -> m b) -> Vector a -> m ()

   rio	RIO.Vector.Boxed

   No documentation available.

5. mapMaybe :: (a -> Maybe b) -> Vector a -> Vector b

   rio	RIO.Vector.Boxed

   No documentation available.

6. mapM_ :: (Monad m, Storable a) => (a -> m b) -> Vector a -> m ()

   rio	RIO.Vector.Storable

   No documentation available.

7. mapMaybe :: (Storable a, Storable b) => (a -> Maybe b) -> Vector a -> Vector b

   rio	RIO.Vector.Storable

   No documentation available.

8. mapM_ :: (Monad m, Unbox a) => (a -> m b) -> Vector a -> m ()

   rio	RIO.Vector.Unboxed

   No documentation available.

9. mapMaybe :: (Unbox a, Unbox b) => (a -> Maybe b) -> Vector a -> Vector b

   rio	RIO.Vector.Unboxed

   No documentation available.

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

    errors	Control.Error

    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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