notElem package:relude

Like notElem but doesn't work on Set and HashSet for performance reasons.

>>> notElem 'x' ("abc" :: String)
True

>>> notElem False (one True :: Set Bool)
...
... Do not use 'elem' and 'notElem' methods from 'Foldable' on Set
Suggestions:
Instead of
elem :: (Foldable t, Eq a) => a -> t a -> Bool
use
member :: Ord a => a -> Set a -> Bool
...
Instead of
notElem :: (Foldable t, Eq a) => a -> t a -> Bool
use
not . member
...