An implementation of groupBy which returns a list of mono traversable

MonoGroupBy.hs

import ClassyPrelude

groupBy' :: IsSequence seq => (Element seq -> Element seq -> Bool) -> seq -> [MinLen (Succ Zero) seq]
groupBy' eq s = case uncons s of
    Nothing -> mempty
    Just (x, xs) -> mlcons x (toMinLenZero ys) : groupBy' eq zs
                      where
                        (ys,zs) = span (eq x) xs