Deconstructive Pattern Matching in Scala

def deconstructList(xs: List[Int]): List[Int] = xs match
    case Nil => Nil
    // Deconstruct a list into head and tail using the cons :: operator.
    // Then, reverse order by concatenating head to tail.
    case y :: ys => deconstructList(ys) ++ List(y)

deconstructList(List(1, 2, 3, 4))

// res0: List[Int] = List(4, 3, 2, 1)