Javascript Inheritance

oop.js

// Super Base Class
function SuperBase() {}

// Base class
function Base(spec) {
    this.name = spec.name; // Define the "name" property
}

// Child class
function Child(spec) {
    Base.call(this, spec); // Call the base class constructor
}

// Wire prototypes
function F2() {} // This F is a temporary function not part of the chain.
F2.prototype = SuperBase;
const intermediateObj2 = new F2(); 
Base.prototype = intermediateObj2; // This is where we put superclass methods
console.assert(Base.prototype.__proto__ === SuperBase)

// Wire prototypes
function F() {} // This F is a temporary function not part of the chain.
F.prototype = intermediateObj2;
const intermediateObj = new F(); 
Child.prototype = intermediateObj; // This is where we put superclass methods
console.assert(Child.prototype.__proto__ === intermediateObj2)

// Add methods to delegate
intermediateObj.sayHello = function () { // Define the "sayHello" method
    return 'Hello, I\'m ' + this.name;
};

// Add methods to super delegate
intermediateObj2.sayHello2 = function () { // Define the "sayHello" method
    return '!!!!!!!!!!!!!!!';
};

// Usage
const object = new Child({ name: 'a prototypal object' });
console.assert(object.__proto__ === intermediateObj)
console.assert(object.__proto__.__proto__ === intermediateObj2)
console.assert(object.__proto__.__proto__.__proto__ === SuperBase)

object.sayHello(); // 'Hello, I\'m SuperBase'
object.sayHello2(); // '!!!!!!!!!!!!!!!'