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Export multiple classes in ES6 modules

I'm trying to create a module that exports multiple ES6 classes. Let's say I have the following directory structure:

my/
└── module/
    ├── Foo.js
    ├── Bar.js
    └── index.js

Foo.js and Bar.js each export a default ES6 class:

// Foo.js
export default class Foo {
  // class definition
}

// Bar.js
export default class Bar {
  // class definition
}

I currently have my index.js set up like this:

import Foo from './Foo';
import Bar from './Bar';

export default {
  Foo,
  Bar,
}

However, I am unable to import. I want to be able to do this, but the classes aren't found:

import {Foo, Bar} from 'my/module';

What is the correct way to export multiple classes in an ES6 module?

just use export without the default
You can only have one default export. Imagine if someone tried to do import SomeClass from 'my/module'. This would automatically import the default module from that path. If you had multiple default exports there, how would it know which one to import?

B
Bill Keller

Try this in your code:

import Foo from './Foo';
import Bar from './Bar';

// without default
export {
  Foo,
  Bar,
}

Btw, you can also do it this way:

// bundle.js
export { default as Foo } from './Foo'
export { default as Bar } from './Bar'
export { default } from './Baz'

// and import somewhere..
import Baz, { Foo, Bar } from './bundle'

Using export

export const MyFunction = () => {}
export const MyFunction2 = () => {}

const Var = 1;
const Var2 = 2;

export {
   Var,
   Var2,
}


// Then import it this way
import {
  MyFunction,
  MyFunction2,
  Var,
  Var2,
} from './foo-bar-baz';

The difference with export default is that you can export something, and apply the name where you import it:

// export default
export default class UserClass {
  constructor() {}
};

// import it
import User from './user'

I am getting an Unexpected token error when building export Foo from './Foo'; export Bar from './Bar'
@inostia note, this is ES6 syntax, you probably need "babel" to support it
I am using babel. I got that error when compiling with webpack. I think I need to do something like export { default as Foo } from './Foo';. I've seen that elsewhere
@inostia I also am experiencing this, export { default as Foo } from './Foo'; was required to actually export it.
S
Syed

Hope this helps:

// Export (file name: my-functions.js)
export const MyFunction1 = () => {}
export const MyFunction2 = () => {}
export const MyFunction3 = () => {}

// if using `eslint` (airbnb) then you will see warning, so do this:
const MyFunction1 = () => {}
const MyFunction2 = () => {}
const MyFunction3 = () => {}

export {MyFunction1, MyFunction2, MyFunction3};

// Import
import * as myFns from "./my-functions";

myFns.MyFunction1();
myFns.MyFunction2();
myFns.MyFunction3();


// OR Import it as Destructured
import { MyFunction1, MyFunction2, MyFunction3 } from "./my-functions";

// AND you can use it like below with brackets (Parentheses) if it's a function 
// AND without brackets if it's not function (eg. variables, Objects or Arrays)  
MyFunction1();
MyFunction2();

i
inostia

@webdeb's answer didn't work for me, I hit an unexpected token error when compiling ES6 with Babel, doing named default exports.

This worked for me, however:

// Foo.js
export default Foo
...

// bundle.js
export { default as Foo } from './Foo'
export { default as Bar } from './Bar'
...

// and import somewhere..
import { Foo, Bar } from './bundle'

P
PaoPao
// export in index.js
export { default as Foo } from './Foo';
export { default as Bar } from './Bar';

// then import both
import { Foo, Bar } from 'my/module';

x
xavier bs

For multiple classes in the same js file, extending Component from @wordpress/element, you can do that :

// classes.js
import { Component } from '@wordpress/element';

const Class1 = class extends Component {
}

const Class2 = class extends Component {
}

export { Class1, Class2 }

And import them in another js file :

import { Class1, Class2 } from './classes';

S
Schmidko

For exporting the instances of the classes you can use this syntax:

// export index.js
const Foo = require('./my/module/foo');
const Bar = require('./my/module/bar');

module.exports = {
    Foo : new Foo(),
    Bar : new Bar()
};

// import and run method
const {Foo,Bar} = require('module_name');
Foo.test();

this ist not ES6 Syntax