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Jonathan Healy21,601 Points
Can someone explain why we construct the RepositoryInterface in the Collection class opposed to implementing it?
I am unclear on the purpose of introducing the Repository Interface, and it's purpose there, inside of the constructor function of the Collection class.
Does this serve a different purpose as opposed to implementing it as we are with the Iterator and Countable interface?
Shoko Ishigaki21,826 Points
In collection class, we have property called repo which is type "RepositoryInterface" (or class implementing RepositoryInterface). Inside constructor, we initialise the repo and then use that repo's function. Hope this helps.