SOLID principles

Liskov Substitution (L)

A subclass must be usable ANYWHERE its parent is, without surprising the caller. If substituting it breaks behaviour, the inheritance is a lie. An animated lesson where the diagram draws itself as the design grows.

  • Lesson 3 of 5
  • Animated diagrams
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SOLID principles

  1. 1Single Responsibility (S)
  2. 2Open / Closed (O)
  3. 3Liskov Substitution (L)
  4. 4Interface Segregation (I)
  5. 5Dependency Inversion (D)
5 lessons, each with diagrams that draw themselves.

What you will learn

  • Substitutability is the contract
  • The famous trap: Square *is-a* Rectangle?
  • The fix

More low-level design

Watch Liskov Substitution (L) take shape

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DSA comes with the all labs plan and every ChaiCode batch.