fold using reduce

gistfile1.txt

private[mada] object Fold {
    def apply[A](v: Vector[A], z: A, op: (A, A) => A): A = {
        (Vector.single(z) ++ v).reduce(op)
    }
}

private[mada] object Folder {
    def apply[A](v: Vector[A], z: A, op: (A, A) => A): Vector[A] = {
        (Vector.single(z) ++ v).reducer(op)
    }
}