Node / JS create new instance right upon import

Question

I want to make an instance of a class without importing the class first and making new afterwards.

Instead of

var mainClass = require('../dist/main'); // has "class Main { ... }"
var mainInstance = new mainClass();

I want

var mainInstance = new require('../dist/main').Main();

But something with the syntax is wrong.

var main = new require('../dist/main').Main();
                                       ^
TypeError: Class constructor Main cannot be invoked without 'new'

Is this even possible? I use a combination of TypeScript and plain JS.

Answer 1

You can use parenthesis to achieve that:

var main = new (require('../dist/main').Main)();

And if your module.exports was solely exporting a class you'd do it like following:

var main = new (require('../dist/main'))();