Extract the options and callback from a function's arguments easily
- Install:
npm install --save extract-opts - Require:
require('extract-opts')
<script type="module">
import * as pkg from '//dev.jspm.io/extract-opts'
</script>This package is published with the following editions:
-
extract-optsaliasesextract-opts/source/index.js -
extract-opts/source/index.jsis esnext source code with require for modules -
extract-opts/edition-browsers/index.jsis esnext compiled for browsers with require for modules
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 optionsExtract 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:
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 nameDiscover the release history by heading on over to the HISTORY.md file.
Discover how you can contribute by heading on over to the CONTRIBUTING.md file.
These amazing people are maintaining this project:
No sponsors yet! Will you be the first?
These amazing people have contributed code to this project:
- Benjamin Lupton — view contributions
- Sean Fridman — view contributions
- Matt Bierner — view contributions
- dependabot-preview[bot] — view contributions
Discover how you can contribute by heading on over to the CONTRIBUTING.md file.
Unless stated otherwise all works are:
- Copyright © 2013+ Bevry Pty Ltd
- Copyright © 2011+ Benjamin Lupton
and licensed under: