The Only Time You Should Use Polymorphism

The only time you should use subtype polymorphism is when you have behavioural variation in the subtypes. I teach two university courses on object oriented programming and I see this problem a lot. Let me explain.

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RECOMMENDED READING:
🛠️ https://geni.us/k8KhT3 (Refactoring)
⭐️ https://geni.us/zzlx (Dependency Injection: Principles, Practices, and Patterns)
💎 https://geni.us/hNDE (Elegant Objects)
🏛️ https://geni.us/IBhtLnh (Clean Architecture)
🧩 https://geni.us/nlbA6 (Head First: Design Patterns)

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CONTENTS:
00:00 Thesis
01:16 Example 1
03:28 Example 2
06:25 Example 3
13:26 Summary