Moduleprotolude-0.3.5Haskell2010

Protolude.Either

valuemaybeToLeft :: r -> Maybe l -> Either l r

valuemaybeToRight :: l -> Maybe r -> Either l r

valueleftToMaybe :: Either l r -> Maybe l

valuerightToMaybe :: Either l r -> Maybe r

valuemaybeEmpty :: Monoid b => (a -> b) -> Maybe a -> b

valuemaybeToEither :: e -> Maybe a -> Either e a

valuefromLeft :: a -> Either a b -> a

Return the contents of a Left-value or a default value otherwise.

Basic usage:

Example2 expressions

>>> fromLeft 1 (Left 3)3>>> fromLeft 1 (Right "foo")1

valuefromRight :: b -> Either a b -> b

Return the contents of a Right-value or a default value otherwise.

Basic usage:

Example2 expressions

>>> fromRight 1 (Right 3)3>>> fromRight 1 (Left "foo")1