Example Improved

ExampleImproved.scala

def addAllCombinations() = {
    val a = Future(Set(1, 2, 3))
    val b = Future(Set(1, 2, 3))
    for {
        x <- SetF(a)
        y <- SetF(b) if y > 2
    } yield {
        x + y
    }
} // Result: Future[Set(4,5,6)]
// PS. To get from SetF to Future[Set[Int]] use SetF.future