both-0.1.1.0: Like Maybe, but with a different Monoid instance.
The Monoid instance for Maybe behaves like so:
instance Monoid a => Monoid (Maybe a) where mappend (Just x) (Just y) = Just $ x <> y mappend (Just x) Nothing = Just x mappend Nothing (Just y) = Just y mappend Nothing Nothing = Nothing mempty = Nothing
Both is a newtype wrapper around Maybe providing this instance:
instance Monoid a => Monoid (Both a) where mappend (Just x) (Just y) = Just $ x <> y mappend _ _ = Nothing mempty = Just mempty
Modules
- Data