Violating the 7 rules of the Liskov Substitution Principle (L in SOLID) leads to code that is difficult to reason about. The 3 type rules can be checked by compilers but the 4 behavioral rules have to be respected by us developers. 

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⭐️ More about LSP in Clean Architecture (Chapter 9): https://geni.us/IBhtLnh

Watch First: https://youtu.be/FdFBYUQCuHQ

📄 The paper: https://dl.acm.org/doi/pdf/10.1145/197320.197383
🏛️ Design By Contract: https://en.wikipedia.org/wiki/Design_by_contract

CONTENTS
00:00 Intro
01:33 Formal Definition
02:56 Robustness Principle
06:09 Type Rules
08:50 Terminology
11:59 Behavioral rules
19:15 Conclusion