L'héritage

Nouvelle instruction extends.

class Developer extends Person {
    constructor(name, age, language) {
        super(name, age);
        this.language = language;
    }

    toString() {
        return super.toString() + ` :: I'm a Developer who likes ${this.language}`;
    }
}

let d = new Developer("Yannick", 29, "JavaScript");
console.log(d.toString());
//  Hi I'm Yannick and I'm 29 years old :: I'm a Developer who likes JavaScript