in the book UML @ Classroom An Introduction to Object-Oriented Modeling is written "Use cases—even included or extending use cases—can always be executed independently. If they can only be executed within the scope of another use case and not independently, they are not use cases and mustnot be depicted as such. Their functionality must then be covered in thedescription of the use case that uses them.", however all examples of extends relationships my Professor gave to me and I found in internet the extending use cases can only be triggered within the scope of the base use case.I'm lost, which one is correct ?
I have a mini-project, I ignored the extending use cases that can't be triggered by any actor, should I draw these extending use cases ?