
            actual = L.Traverse(combined, typeof(Maybe<string>), i => Maybe.Just(i + ""), FuncList.Make(FuncList.Make<int>())).ToMaybe();

            Assert.Single(actual.Value());
            Assert.Empty(actual.Value()[0]);

            actual = L.Traverse(combined, typeof(Maybe<string>), i => Maybe.JustIf(i % 2 == 0, () => i + ""), FuncList.Make(FuncList.Make(0,2,4,6), FuncList.Make(10,12))).ToMaybe();