Learn ECMAScript - Second Edition

Overriding the result of the constructor method

The constructor method, by default, returns the new instance if there is no return statement in it. If there is a return statement, then any value in the return statement is returned. This might seem a little weird if you're coming from a language like C++ as you cannot usually return any value from the constructor there.

Here is an example to demonstrate this:

class myClass {     constructor() {         return Object.create(null);     } } console.log(new myClass() instanceof myClass); //Output "false"