Signature of sorted method in SeqLike

Question

I don't understand the purpose for the signature of the

sorted

method within the

SeqLike

trait:

def sorted[B >: A](implicit ord: Ordering[B]): Repr

More precise, I don't get:

Perhaps you can shed some light on this.

Thanks in advance for the effort in answering!

Answer 1

The method takes an implicit Ordering which should be able to handle some supertype of A (hence B >: A). I.e. you should be able to use an Ordering[AnyVal] to compare Int values (as AnyVal is a supertype of Int).
Repr is a type parameter of the SeqLike trait itself (SeqLike[+A, +Repr]) described as "the type of the actual collection containing the elements". This is meant to ensure that methods like sorted will return a collection of the same type (e.g. List.sorted will still be a List).

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