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  1. mapAndUnzipM :: Applicative m => (a -> m (b, c)) -> [a] -> m ([b], [c])

    verset Verset

    The mapAndUnzipM function maps its first argument over a list, returning the result as a pair of lists. This function is mainly used with complicated data structures or a state monad.

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

    verset Verset

    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]

  3. mappend :: Monoid a => a -> a -> a

    verset Verset

    An associative operation NOTE: This method is redundant and has the default implementation mappend = (<>) since base-4.11.0.0. Should it be implemented manually, since mappend is a synonym for (<>), it is expected that the two functions are defined the same way. In a future GHC release mappend will be removed from Monoid.

  4. mapChildren :: String -> Element -> (Element -> Maybe a) -> Maybe [a]

    xml-helpers Text.XML.Light.Helpers

    Map the given function over the children of the given element with the given name.

  5. mapChildrenWithAttName :: String -> Element -> (Element -> Maybe a) -> Maybe [a]

    xml-helpers Text.XML.Light.Helpers

    Map the given function over the children of the given element that have an attribute "name" matching the given string.

  6. mapElements :: String -> Element -> (Element -> Maybe a) -> Maybe [a]

    xml-helpers Text.XML.Light.Helpers

    Map the given function over all subelements of the given element with the given name.

  7. mapElementsWithAttName :: String -> Element -> (Element -> Maybe a) -> Maybe [a]

    xml-helpers Text.XML.Light.Helpers

    Map the given function over the subelements of the given element that have an attribute "name" matching the given string.

  8. maps :: SearchEngine

    xmonad-contrib XMonad.Actions.Search

    No documentation available.

  9. mapE :: (Bool -> a -> b) -> Either a a -> Either b b

    xmonad-contrib XMonad.Util.Stack

    Map a function across both Lefts and Rights. The Bool argument is True in a Right, False in a Left.

  10. mapEM :: Monad m => (Bool -> a -> m b) -> Either a a -> m (Either b b)

    xmonad-contrib XMonad.Util.Stack

    Monadic version of mapE

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