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extract-opts

Extract the options and callback from a function's arguments easily

Extract Options & Callback


Extract the options and callback from a function's arguments easily

  • Install: npm install --save extract-opts
  • Module: require('extract-opts')
    • Install: npm install --save extract-opts
    • Module: require('extract-opts')
    • CDN URL: //wzrd.in/bundle/extract-opts@3.3.1
      • Install: ender add extract-opts
      • Module: require('extract-opts')
      • Editions

        This package is published with the following editions:

        • extract-opts aliases extract-opts/index.js which uses Editions to automatically select the correct edition for the consumers environment
        • extract-opts/source/index.js is Source + ESNext + Require
        • extract-opts/es2015/index.js is Babel Compiled + ES2015 + Require

        Older environments may need Babel's Polyfill or something similar.

        var log = console.log.bind(console)
        var extractOptsAndCallback = require('extract-opts')
         
        // fs.readFile(filename, [options], callback) 
        function readFile (filenameoptsnext) {
        // 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 

        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:

        var log = console.log.bind(console)
        function extractOptsAndCallback (optsnextconfig) {
        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

        Discover 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:

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        These amazing people have contributed code to this project:

        Discover how you can contribute by heading on over to the CONTRIBUTING.md file.

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