Node.js v6.2.0 class extends is not a function error?

Question

So I'm trying to extend a class in node js and the compiler keeps returning the following error:

TypeError: Class extends value #<Object> is not a function or null 

I checked that I was exporting the class correctly and I am, any ideas? I'll post my code below:

/handler/venue.js:

var VenueViews = require('../views/venue'); // If I remove this the error will dissapear (as expected) class Venue {   constructor(data) {     this.setDataHere = data;   }    main () {    var View = new VenueViews(); // This doesn't run   }   }  module.exports = Venue; 

/views/venue.js:

var Venue = require('../handlers/venue'); console.log  (Venue) // This returns {} ???  class VenueViews extends Venue {   constructor() {     super();   } }  module.exports = VenueViews; 

I know that node supports these es6 features, so I'm unsure why they aren't working?

Edit:

I'm not sure if this is suppose to happen but, when I log my Venue require it returns an empty object {}.

console.log  (Venue) // This returns {} ??? 

Answer 1

So it turns out I had a circular reference in my code, where I was importing the class that was extending, into the class that itself was extending (tongue twister :P).

The obvious fix was to simply remove the extends reference and find another way of doing what I was trying to achieve. In my case it was passing the Venue class properties down into the VenueViews constructor.

E.g var x = VenueViews(this)

Answer 2

In my instance, it was the same issue as @James111 was experiencing (circular import) due to a factory pattern I was trying to set up in Typescript. My fix was to do move the code into files, similar to the following:

// ./src/interface.ts import { ConcreteClass } from './concrete';  export interface BaseInterface {    someFunction(): any; }  export class Factory {   static build(): BaseInterface {      return new ConcreteClass();   } }  // ./src/base.ts import { BaseInterface } from './interface'; class BaseClass implements BaseInterface {   someFunction(): any {     return true;   } }  // ./src/concrete.ts import { BaseClass } from './base'; export class ConcreteClass extends BaseClass {   someFunction(): any {     return false;   } }