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  • Yu Sasaki thinks this is interesting:

The rule of polymorphism states that classes can be altered according to their state, in effect making them a different object based on values of attributes, type, or function. We use polymorphism in almost every coding situation, especially patterns. This rule gives us the power to use abstraction and inheritance, allowing inherited members to change according to how they implement their base class. It also allows us to change a class’s purpose and function based on its current state. Polymorphism helps interfaces change their implementation class type simply by allowing several different classes to use the same interface. Polymorphic declarations of specific implementations of classes with a common base or i...

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Cover of Design Patterns

Note

Polymorphism