[![NPM version][npm-image]][npm-url] [![Build Status][travis-image]][travis-url] [![Dependency Status][daviddm-image]][daviddm-url] [![devDependency Status][daviddm-dev-image]][daviddm-dev-url] # Optional Require node.js require that let you handle module not found error without try/catch. Allows you to gracefully require a module only if it exists and contains no error. ## Why not try/catch? So why not just do: ```ts let some; try { some = require("some-optional-module"); } catch { // do nothing } ``` 1. You need to keep the variable outside: `let some` before try/catch 2. If `"some-optional-module"` contains error itself, above code will silently ignore it, leaving you, and more importantly, your users, puzzling on why it's not working. ## Usage TypeScript: ```ts import { optionalRequire } from "optional-require"; const some = optionalRequire("some-optional-module"); ``` JavaScript: ```js const { optionalRequire } = require("optional-require"); const foo = optionalRequire("foo") || {}; const bar = optionalRequire("bar", true); // true enables console.log a message when not found const xyz = optionalRequire("xyz", "test"); // "test" enables console.log a message with "test" added. const fbPath = optionalRequire.resolve("foo", "foo doesn't exist"); // relative module path works - *but* you need to pass in `require` from your file const rel = optionalRequire("../foo/bar", { require }); ``` ### Binding `require` The default `optionalRequire` uses `require` from the context of this module. While you can pass in your `require` in `options`, if you want to create your own function that's bound to your `require`, you can do it with `makeOptionalRequire`: ```ts import { makeOptionalRequire } from "optional-require"; const optionalRequire = makeOptionalRequire(require); // now you can optional require files in same dir as your file const myModule = optionalRequire("./my-module"); ``` ### Legacy Usage In older versions, this module exports `makeOptionalRequire` directly and this is the legacy usage in JavaScript, which is still supported: ```js const optionalRequire = require("optional-require")(require); const foo = optionalRequire("foo") || {}; const bar = optionalRequire("bar", true); // true enables console.log a message when not found const xyz = optionalRequire("xyz", "test"); // "test" enables console.log a message with "test" added. const fbPath = optionalRequire.resolve("foo", "foo doesn't exist"); const rel = optionalRequire("../foo/bar"); // relative module path works ``` ## API # LICENSE Apache-2.0 © [Joel Chen](https://github.com/jchip) [travis-image]: https://travis-ci.org/jchip/optional-require.svg?branch=master [travis-url]: https://travis-ci.org/jchip/optional-require [npm-image]: https://badge.fury.io/js/optional-require.svg [npm-url]: https://npmjs.org/package/optional-require [daviddm-image]: https://david-dm.org/jchip/optional-require/status.svg [daviddm-url]: https://david-dm.org/jchip/optional-require [daviddm-dev-image]: https://david-dm.org/jchip/optional-require/dev-status.svg [daviddm-dev-url]: https://david-dm.org/jchip/optional-require?type=dev