import-lazy

by sindresorhus

sindresorhus / import-lazy

Import a module lazily

207 Stars 10 Forks Last release: over 1 year ago (v4.0.0) MIT License 40 Commits 7 Releases

Available items

No Items, yet!

The developer of this repository has not created any items for sale yet. Need a bug fixed? Help with integration? A different license? Create a request here:

import-lazy Build Status

Import a module lazily

Install

$ npm install import-lazy

Usage

// Pass in `require` or a custom import function
const importLazy = require('import-lazy')(require);
const _ = importLazy('lodash');

// Instead of referring to its exported properties directly… _.isNumber(2);

// …it's cached on consecutive calls _.isNumber('unicorn');

// Works out of the box for functions and regular properties const stuff = importLazy('./math-lib'); console.log(stuff.sum(1, 2)); // => 3 console.log(stuff.PHI); // => 1.618033

Note

Destructuring will cause it to fetch eagerly

While you may be tempted to do leverage destructuring, like this:

const {isNumber, isString} = importLazy('lodash');

Note that this will cause immediate property access, negating the lazy loading, and is equivalent to:

import {isNumber, isString} from 'lodash';

Usage with bundlers

If you're using a bundler, like Webpack, you'll have to import your modules like this in order to have them properly bundled:

const importLazy = require('import-lazy');

const _ = importLazy(() => require('lodash'))();

Related

  • resolve-from - Resolve the path of a module from a given path
  • import-from - Import a module from a given path
  • resolve-pkg - Resolve the path of a package regardless of it having an entry point
  • lazy-value - Create a lazily evaluated value
  • define-lazy-prop - Define a lazily evaluated property on an object

Get professional support for this package with a Tidelift subscription
Tidelift helps make open source sustainable for maintainers while giving companies
assurances about security, maintenance, and licensing for their dependencies.

We use cookies. If you continue to browse the site, you agree to the use of cookies. For more information on our use of cookies please see our Privacy Policy.