import-lazy

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

Warning: 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';

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

License

MIT © Sindre Sorhus

Current Tags

• 4.0.0                                ...           latest (6 years ago)

4 Versions

• 4.0.0                                ...           6 years ago
• 3.1.0                                ...           7 years ago
• 3.0.0                                ...           7 years ago
• 2.1.0                                ...           8 years ago