Why not inherit from List?

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悲哀的现实
悲哀的现实 2020-11-21 05:39

When planning out my programs, I often start with a chain of thought like so:

A football team is just a list of football players. Therefore, I should

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  •  轮回少年
    2020-11-21 05:58

    This reminds me of the "Is a" versus "has a" tradeoff. Sometimes it is easier and makesmore sense to inherit directly from a super class. Other times it makes more sense to create a standalone class and include the class you would have inherited from as a member variable. You can still access the functionality of the class but are not bound to the interface or any other constraints that might come from inheriting from the class.

    Which do you do? As with a lot of things...it depends on the context. The guide I would use is that in order to inherit from another class there truly should be an "is a" relationship. So if you a writing a class called BMW, it could inherit from Car because a BMW truly is a car. A Horse class can inherit from the Mammal class because a horse actually is a mammal in real life and any Mammal functionality should be relevant to Horse. But can you say that a team is a list? From what I can tell, it does not seem like a Team really "is a" List. So in this case, I would have a List as a member variable.

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