Unable to understand <x> .prototype.constructor?

Question

I have two classes Car and Maruti . When I use inheritance, assigning a Maruti prototype to the new Car object. Why do I need to install Maruti.prototype.constructor in Maruti . Shown in the code below.

 function Car(){ } function Maruti(){ } Maruti.prototype = new Car() Maruti.prototype.constructor = Maruti 

Unable to understand the last line of code. Can someone explain in detail?

Answer 1

If Maruti inherit Car using Maruti.prototype = new Car() , you need to reset the constructor property for the Maruti class using Maruti.prototype.constructor=Maruti; otherwise Maruti instances will have a Car constructor.

Answer 2

Considering this,

 function Car(){ } 

and that the constructor property is a function prototype property

Now, if you look at the constructor of a new instance of Car

new Car().constructor === Car

You see that this is Car , then you install

 function Maruti(){ } Maruti.prototype = new Car(); 

Remember that new Car().constructor === Car ?,
As such, it is now Maruti.prototype.constructor === Car , so it is shaded to an instance of Maruti , overriding the original Maruti.prototype.constructor

So, if you create a new instance of Maruti and search for the constructor

new Maruti().constructor === Car

You see this is Car , although new Maruti() is built on Maruti , not Car

Answer 3

Before setting Maruti.prototype = new Car prototype of Maruti has only one property, constructor , which is set as Maruti :

 function Car() {} function Maruti(){} console.log(Maruti.prototype); // logs the following // { // constructor: Maruti // } Maruti.prototype = new Car; Maruti.prototype.constructor = Maruti; 

After you set the prototype from Maruti to the new Car , the constructor property is lost (because its not the same object). Instead, Maruti.prototype.constructor will now be Car (because it is inherited from Car.prototype ). Therefore, we again set the constructor property to Maruti .

For a better explanation, consider the following answer: fooobar.com/questions/85508 / ...