Understanding what new keyword do and the prototype inheritance.

understanding_new_keyword.js

'use strict'

function Scope() {
	this.va = '123';
};

Scope.prototype.va = 'abc';

var s = new Scope();

/* The properties in the prototype can be override */
console.log(s.va); // -> '123'
/* The prototype of the newly created object is undefined */
console.log(s instanceof(Scope), s.prototype); // -> true undefined
/* Constructor is automatically set to parent */
console.log(s.constructor === Scope); // -> true

/*
When new Xxx() is called, JavaScript does four things:

1. It creates a new object.
2. It sets the constructor property of the object to Vehicle.
3. It sets up the object to DELEGATE to Xxx.prototype.
4. It calls Xxx() in the context of the new object.
*/