:: (a -> c) -> (b -> d) -> Either a b -> Either c d package:diagrams-lib

Map over both arguments at the same time.
bimap f g ≡ first f . second g

Examples

>>> bimap toUpper (+1) ('j', 3)
('J',4)
>>> bimap toUpper (+1) (Left 'j')
Left 'J'
>>> bimap toUpper (+1) (Right 3)
Right 4