Instantiation of traits

Question
4

It’s because in A with B , if A is a trait, the list of parents is extended to include the supertype of A , as per 5.1 in the spec.

But why the difference between new A with B and new A? Why not let new A mean new Object with A if A is a trait?

From a user’s perspective this irregularity is unexpected and confusing:

trait A
trait B
trait C
trait D
new A with B with C with D
new A with B with C
new A with B
new A {}