# Extract Options & Callback Status of the GitHub Workflow: bevry NPM version NPM downloads
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Discord server badge Twitch community badge Extract the options and callback from a function's arguments easily ## Usage ```javascript var log = console.log.bind(console) var extractOptsAndCallback = require('extract-opts') // fs.readFile(filename, [options], callback) function readFile(filename, opts, next) { // Extract options and callback var args = extractOptsAndCallback(opts, next) opts = args[0] next = args[1] // Forward for simplicities sake require('fs').readFile(filename, opts, next) } // Test it readFile('package.json', log) // works with no options readFile('package.json', null, log) // works with null options readFile('package.json', { next: log }) // works with just options ``` ### Customisation Extract Options and Callback also supports a third argument. You can use this third argument to customize the `completionCallbackNames` property that defaults to `['next']`. This is useful if your completion callback has other names besides `next`. Allowing you to do the following: ```javascript var log = console.log.bind(console) function extractOptsAndCallback(opts, next, config) { if (config == null) config = {} if (config.completionCallbackNames == null) config.completionCallbackNames = ['next', 'complete', 'done'] return require('extract-opts')(opts, next, config) } // The readFile method as before // Test it readFile('package.json', { next: log }) // works the standard completion callback name readFile('package.json', { complete: log }) // works with our custom completion callback name readFile('package.json', { done: log }) // works with our custom completion callback name ``` ## Install ### [npm](https://npmjs.com "npm is a package manager for javascript") - Install: `npm install --save extract-opts` - Import: `import * as pkg from ('extract-opts')` - Require: `const pkg = require('extract-opts')` ### [jspm](https://jspm.io "Native ES Modules CDN") ``` html ``` ### [Editions](https://editions.bevry.me "Editions are the best way to produce and consume packages you care about.") This package is published with the following editions: - `extract-opts` aliases `extract-opts/index.cjs` which uses the [Editions Autoloader](https://github.com/bevry/editions "You can use the Editions Autoloader to autoload the appropriate edition for your consumers environment") to automatically select the correct edition for the consumer's environment - `extract-opts/source/index.js` is [ESNext](https://en.wikipedia.org/wiki/ECMAScript#ES.Next "ECMAScript Next") source code for [Node.js](https://nodejs.org "Node.js is a JavaScript runtime built on Chrome's V8 JavaScript engine") 6 || 8 || 10 || 12 || 14 || 16 || 18 || 20 || 21 with [Require](https://nodejs.org/dist/latest-v5.x/docs/api/modules.html "Node/CJS Modules") for modules - `extract-opts/edition-browsers/index.js` is [ESNext](https://en.wikipedia.org/wiki/ECMAScript#ES.Next "ECMAScript Next") compiled for web browsers with [Require](https://nodejs.org/dist/latest-v5.x/docs/api/modules.html "Node/CJS Modules") for modules - `extract-opts/edition-node-4/index.js` is [ESNext](https://en.wikipedia.org/wiki/ECMAScript#ES.Next "ECMAScript Next") compiled for [Node.js](https://nodejs.org "Node.js is a JavaScript runtime built on Chrome's V8 JavaScript engine") 4 || 6 || 8 || 10 || 12 || 14 || 16 || 18 || 20 || 21 with [Require](https://nodejs.org/dist/latest-v5.x/docs/api/modules.html "Node/CJS Modules") for modules ## History [Discover the release history by heading on over to the `HISTORY.md` file.](https://github.com/bevry/extract-opts/blob/HEAD/HISTORY.md#files) ## Backers ### Code [Discover how to contribute via the `CONTRIBUTING.md` file.](https://github.com/bevry/extract-opts/blob/HEAD/CONTRIBUTING.md#files) #### Authors - [Benjamin Lupton](https://balupton.com) — Accelerating collaborative wisdom. #### Maintainers - [Benjamin Lupton](https://balupton.com) — Accelerating collaborative wisdom. #### Contributors - [Benjamin Lupton](https://github.com/balupton) — [view contributions](https://github.com/bevry/extract-opts/commits?author=balupton "View the GitHub contributions of Benjamin Lupton on repository bevry/extract-opts") - [Matt Bierner](https://github.com/mjbvz) — [view contributions](https://github.com/bevry/extract-opts/commits?author=mjbvz "View the GitHub contributions of Matt Bierner on repository bevry/extract-opts") - [Sean Fridman](https://github.com/sfrdmn) — [view contributions](https://github.com/bevry/extract-opts/commits?author=sfrdmn "View the GitHub contributions of Sean Fridman on repository bevry/extract-opts") ### Finances GitHub Sponsors donate button ThanksDev donate button Patreon donate button Liberapay donate button Buy Me A Coffee donate button Open Collective donate button crypto donate button PayPal donate button #### Sponsors - [Andrew Nesbitt](https://nesbitt.io) — Software engineer and researcher - [Balsa](https://balsa.com) — We're Balsa, and we're building tools for builders. - [Codecov](https://codecov.io) — Empower developers with tools to improve code quality and testing. - [Poonacha Medappa](https://poonachamedappa.com) - [Rob Morris](https://github.com/Rob-Morris) - [Sentry](https://sentry.io) — Real-time crash reporting for your web apps, mobile apps, and games. - [Syntax](https://syntax.fm) — Syntax Podcast #### Donors - [Andrew Nesbitt](https://nesbitt.io) - [Armen Mkrtchian](https://mogoni.dev) - [Balsa](https://balsa.com) - [Chad](https://opencollective.com/chad8) - [Codecov](https://codecov.io) - [dr.dimitru](https://veliovgroup.com) - [Elliott Ditman](https://elliottditman.com) - [entroniq](https://gitlab.com/entroniq) - [GitHub](https://github.com/about) - [Hunter Beast](https://cryptoquick.com) - [Jean-Luc Geering](https://github.com/jlgeering) - [Michael Duane Mooring](https://mdm.cc) - [Michael Harry Scepaniak](https://michaelscepaniak.com) - [Mohammed Shah](https://github.com/smashah) - [Mr. Henry](https://mrhenry.be) - [Nermal](https://arjunaditya.vercel.app) - [Pleo](https://pleo.io) - [Poonacha Medappa](https://poonachamedappa.com) - [Rob Morris](https://github.com/Rob-Morris) - [Robert de Forest](https://github.com/rdeforest) - [Sentry](https://sentry.io) - [ServieJS](https://github.com/serviejs) - [Skunk Team](https://skunk.team) - [Syntax](https://syntax.fm) - [WriterJohnBuck](https://github.com/WriterJohnBuck) ## License Unless stated otherwise all works are: - Copyright © [Benjamin Lupton](https://balupton.com) and licensed under: - [Artistic License 2.0](http://spdx.org/licenses/Artistic-2.0.html)