How to access one of multiple traits of superclass?

Question

I have a trait which is implemented from some other traits. Each of these traits override the behavior of the supertrait and are mixed-in to a class:

trait T { 
  def name = "t"
}
trait T1 extends T {
  abstract override def name = "t1"
}
trait T2 extends T {
  abstract override def name = "t2"
}
class C extends T with T1 with T2 {
  def printName = super.name
}

Now, in class C I want to access the behavior not of the last mixed-in trait but the behavior of one of these traits. Is this possible?

score 28 · Accepted Answer · answered Sep 23 '11 at 09:09

28

It is possible to specialize the super-call to a specific trait:

class C extends T with T1 with T2 {
  def printName = super[T1].name
}

answered Sep 23 '11 at 09:09

kiritsuku

52,967
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10

This is only possible if the `T1` above is a direct super trait. – axel22 Sep 23 '11 at 09:14
The question and answer, both by same person? – Nawaz Sep 24 '11 at 04:39
4

@Nawaz Why not? It is the sense of SO to share knowledge. Because I haven't found a similar question or someone who answered this already, I created both question and answer. – kiritsuku Sep 24 '11 at 08:10
Does the [superclass] not work for an actual class i.e. not a trait? i can't get this to work. – WestCoastProjects Oct 02 '14 at 03:32
@javadba Without seeing your code I can only guess what is broken. Just ask a new question. – kiritsuku Oct 02 '14 at 12:56
Another awesome feature of Scala forgotten and rediscovered after few years! – Jus12 Oct 10 '16 at 09:57

How to access one of multiple traits of superclass?

1 Answers1