qsort algorithm in Scala

QSort.scala

 def qsort[T <% Ordered[T]](list: List[T]): List[T] = {
  
    list match {
 
      case Nil => Nil
      case x:: xs =>
        val (before, after) = xs partition (_ < x )
        qsort (before) ++ (x :: qsort(after))
  
    }
  }