Class Syntax (constructor, extends, super, get, set)

Expert-Level Explanation

In JavaScript, class syntax provides a more clear and concise way to create objects and deal with inheritance. A class can include a constructor (for initialising new objects), methods to define behaviours, and can extend other classes. The extends keyword is used for inheritance,super for calling the parent's constructor, and get/set for accessing properties in a controlled way.

Creative Explanation

Think of a class as a blueprint for building a house. The constructor is like the ground-breaking ceremony where you lay down the foundation. extends is like designing your house based on an existing model but with your own modifications. super is like referencing the original blueprint when making these modifications. get andset are like having security guards at the gate who control who enters and exits.

Practical Explanation with Code

class Animal {
    constructor(name) {
        this.name = name;
    }
    speak() {
        console.log(`${this.name} makes a sound.`);
    }
}

class Dog extends Animal {
    constructor(name, breed) {
        super(name); // Call the super class constructor
        this.breed = breed;
    }
    speak() {
        console.log(`${this.name} barks.`);
    }
}

let dog = new Dog("Rex", "Golden Retriever");
dog.speak(); // Rex barks.

Real-world Example

Imagine a class like a recipe for a specific type of cake. You can create many cakes (objects) from this recipe, and if you want a different flavour (subclass), you can modify the original recipe (inheritance) while keeping the basic steps (super). The get and set methods are like having specific instructions on how to add or remove ingredients.