Objects and Data Models
Design objects that own coherent state, protect rules, and collaborate through small interfaces.
Functions, collections, and input validation.
Model related state and behavior using classes while preserving object invariants through encapsulation, validation, and proper method design.
Read in order, or jump to what you need.
Every lesson builds on the one before it. Open any lesson to read the explanation, run the examples, and try the practice challenges.
- 06.01Classes and Objects4 min
Bring related state and behavior together without turning every function into a class.
- 06.02Methods and Properties4 min
Design readable object interfaces with deliberate mutation, computed attributes, and alternative constructors.
- 06.03Composition and Inheritance4 min
Choose relationships that let objects collaborate without creating fragile hierarchies.
- 06.04Inheritance in depth4 min
Use single, multilevel, and multiple inheritance deliberately, and understand the method resolution order that makes cooperative super calls work.
- 06.05Dataclasses and Models4 min
Define records with useful generated behavior while keeping validation and mutability decisions explicit.
Ready to move on?
Create two independent object instances, update one, and verify that a rejected update leaves the original state unchanged—invariants are preserved.
Open the module self-check