What is the difference between composition and inheritance in JavaScript OOP?

What is the difference between composition and inheritance in JavaScript OOP?

In JavaScript OOP, inheritance allows a class to inherit properties and methods from another class, while composition involves building complex objects by combining simpler ones.

Can you give me an example of inheritance in JavaScript?

Sure! Here's a simple example:

class Animal {
    speak() {
        console.log('Animal speaks');
    }
}

class Dog extends Animal {
    speak() {
        console.log('Dog barks');
    }
}

const dog = new Dog();
dog.speak(); // Output: Dog barks

And what about composition? How does it work?

Composition can be illustrated like this:

class Bark {
    speak() {
        console.log('Dog barks');
    }
}

class Dog {
    constructor() {
        this.bark = new Bark();
    }
    speak() {
        this.bark.speak();
    }
}

const dog = new Dog();
dog.speak(); // Output: Dog barks

Which one is better to use in practice?

It depends on the situation! Composition is often favored for its flexibility and reusability, while inheritance can be simpler for straightforward hierarchies.