Can I use alias with NodeJS require function?

Question

I have an ES6 module that exports two constants:

export const foo = "foo";
export const bar = "bar";

I can do the following in another module:

import { foo as f, bar as b } from 'module';
console.log(`${f} ${b}`); // foo bar

When I use NodeJS modules, I would have written it like this:

module.exports.foo = "foo";
module.exports.bar = "bar";

Now when I use it in another module can I somehow rename the imported variables as with ES6 modules?

const { foo as f, bar as b } = require('module'); // invalid syntax
console.log(`${f} ${b}`); // foo bar

How can I rename the imported constants in NodeJS modules?

foo isn't exported directly, it's a property of exports (which I'm presuming module gets exported?), so you can't alias it, not in the import/require anyway — Liam
– Liam, Commented Feb 23, 2018 at 16:58

Jonas Wilms · Accepted Answer · 2020-07-02 14:01:22Z

293

Sure, just use the object destructuring syntax:

 const { old_name: new_name, foo: f, bar: b } = require('module');

edited Jul 2, 2020 at 14:01

answered Feb 23, 2018 at 17:02

Jonas Wilms

139k20 gold badges164 silver badges164 bronze badges

Sign up to request clarification or add additional context in comments.

4 Comments

technogeek1995 Over a year ago

For clarification: const { prevName: newName } = require('../package.json'); I flipped it around and couldn't figure out why it didn't work for a couple minutes.

Nahum Over a year ago

@technogeek1995 you are the real MVP. logged in to SO to thank you!

Beau Over a year ago

If you're requiring a default export (something like export default foo;), "default" is the name so you'd do: const { default: newName } = require('module');

Muhammad Mubashirullah Durrani Over a year ago

In case, its module.exports = () => {some function} then you can assign any variable name you want. const anything = require('module');

barnski · Accepted Answer · 2018-02-23 17:02:19Z

17

It is possible (tested with Node 8.9.4):

const {foo: f, bar: b} = require('module');
console.log(`${f} ${b}`); // foo bar

answered Feb 23, 2018 at 17:02

barnski

1,74214 silver badges19 bronze badges

Comments

clusterBuddy · Accepted Answer · 2020-09-05 19:49:08Z

4

Yes, a simple destructure would adhere to your request.

Instead of:

var events = require('events');
var emitter = new events.EventEmitter();

You can write:

const emitter = {EventEmitter} = require('events');

emitter() will alias the method EventEmitter()

Just remember to instantiate your named function: var e = new emitter(); 😁

edited Sep 5, 2020 at 19:49

answered Sep 5, 2020 at 19:44

clusterBuddy

1,55415 silver badges42 bronze badges

1 Comment

tugrul Over a year ago

There is a little confusion. emitter variable is not alias of EventEmitter. It presents entire module. Testable code is const events = {EventEmitter} = require('events'); assert(events.EventEmitter === EventEmitter);

Rafael Paulino · Accepted Answer · 2018-02-23 16:57:12Z

-5

I would say it is not possible, but an alternative would be:

const m = require('module');
const f = m.foo;
const b = m.bar;

answered Feb 23, 2018 at 16:57

Rafael Paulino

5812 silver badges9 bronze badges

Collectives™ on Stack Overflow

Can I use alias with NodeJS require function?

4 Answers 4

4 Comments

Comments

Instead of:

You can write:

1 Comment

Comments

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

4 Answers 4

4 Comments

Comments

Instead of:

You can write:

1 Comment

Comments

Your Answer

Sign up or log in

Post as a guest

Linked

Related