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About JS: Dive into Classes

JavaScript, like any other class language, pays a lot of attention to class organization. This is all done with the aim of being able to reuse code better (in class-based languages, these tricks aren't needed if the language doesn't have classes) and make fewer errors.

On the one hand, this is good, on the other hand, the current possibilities are so varied that one task can be implemented in dozens of ways. The number of combinations of different approaches generates whole schools and directions on how to write code. How often you should use inheritance? When is the Liskov principle needed?

In this course, we'll take a deep dive into class organization and the concept of inheritance. Let's learn how to build class hierarchies correctly, taking the Liskov substitution principle into account. Then we'll learn why inheritance is almost always a bad way to organize code (but popular because it's easy to do) and why using composition is preferred.

Inheritance involves a lot of new things. Inheritance-specific design patterns start to emerge. Inheritance affects how polymorphic code works, though you don't necessarily need polymorphic code to use it. This should be looked at separately.

Finally, we'll introduce you to a really interesting concept - mixins.


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