scala f-bounded types explanation

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The advantage would come when it looks something like this:

trait Container[A <: Container[A]] extends Ordered[A] {
  def clone: A
  def pair: (A, A) = (clone, clone)
}

class MyContainer extends Container[MyContainer] {
  def clone = new MyContainer
}

Now you get pair for free, and you get the correct return type. Without something like this you must manually override every single method that returns the same type (lots of pointless boilerplate), or you lose specificity in your types as soon as you call a non-overridden method.

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