Extra Maybe functions.
maybe : b -> (a -> b) -> Maybe a -> b
Takes a default value, a function, and a Maybe
value. If the Maybe
value
is Nothing
, the function returns the default value. Otherwise, it applies the
function to the value inside the Just
and returns the result.
mapMaybe : (a -> Maybe b) -> List a -> List b
Version of map which throw out elements.
catMaybes : List (Maybe a) -> List a
Takes a list of Maybe
and returns a list of all the Just
values.
isJust : Maybe a -> Basics.Bool
Returns True
if its argument is of the form Just _
isNothing : Maybe a -> Basics.Bool
Returns True
if its argument is Nothing