Modules Namespace

The Module Namespace Object

When you use the syntax:

import * as name from "module";

JavaScript creates a module namespace object.

This is an immutable object that contains all the exported bindings from that module.

Example

// math_module.js

export const PI = 3.14159;

export function add(a, b) {

  return a + b;

}

export function multiply(a, b) {

  return a * b;

}

Module Namespace Support

Module namespace support refers to the mechanism that allows you to import all exports from a module into a single namespace object.

Note: The Module Namespace feature is a part of the ES Modules introduced in ECMAScript 2015 to help organize and access modules in a consistent way.

Module Namespace Features

Related Syntax

import { add } from "./math_module.js";

import math from "./math_module.js";

import * as math from "./math_module.js";

Module Namespace Export

Module namespace export refers to exporting an entire imported module namespace object from another module.

Namespace Export

Normally, you import all of a module's exports into a module namespace object like this:

Example

import * as math from "./math_module.js";

let myPi = math.PI;

let result = math.add(2, 3);

With module namespace exports, you can re-export that entire namespace from your own module - without having to import it first:

utilities.js

export * from "./math_module.js";

Example

import * as math from "./utilities.js";

Note: The syntax export * as name from "module" was added in ECMAScript 2020.

Syntax Overview

Aggregator Scripts

An aggregator script is a script used only to import and re-export items from other modules.

Instead of filling your top module with many import statements, you can use a single aggregator script to do it all.