append method

@override Option<A> append(Option<A> oa1, Option<A> oa2)

Implementation

@override Option<A> append(Option<A> oa1, Option<A> oa2) => oa1.fold(() => oa2, (a1) => oa2.fold(() => oa1, (a2) => some(_tSemigroup.append(a1, a2))));