Question

I want to extend the type ‘Number’ with a new function and hence I have to define a prototype. When I think about this, I get a bunch of questions:

1. Does Number inherit from both Object.prototype as well as Function.prototype?
2. Is ‘Number’ an ‘Object’ or a ‘Function’?
3. When should I define an object as a prototype for Number? Does it make sense?

Answer 1

1- True. Number instanceof Object returns true also Function instanceof Object returns true. So Number has all methods that Object and Function has.

2- Number is a function. typeof Number returns “function”.

3- If you want to add a method to Number’s prototype, just use

Number.prototype.METHOD_NAME = function() {
    // your logic
}

Then you can call your method on all numbers like 1..METHOD_NAME()