scalaz.Monoid
Monoid instances must satisfy scalaz.Semigroup.SemigroupLaw and 2 additional laws:
forall a. append(zero, a) == a
forall a. append(a, zero) == a
Monoid instances must satisfy scalaz.Semigroup.SemigroupLaw and 2 additional laws:
forall a. append(zero, a) == a
forall a. append(a, zero) == a