polyfills

How do you wrap a polyfill script as an AMD module and conditionally load it using Modernizr and RequireJS? (Figured it out while I was drafting my question - posting answer for anyone else trying to do the same thing.) The polyfill I needed to load was jquery-placeholder for browsers that don't support input placeholders. It does not provide AMD support out of the box. First I wrapped it as an AMD module like this: define(['jquery'], function ($) { (function(window, document, $) { ... polyfill ... }(this, document, jQuery)); }); Then in main.js I used Modernizr to conditionally require() the

Do I need to include import "babel-polyfill" to the top of each entry file, or is it enough to have babel-polyfill rule just in webpack.config file? I am confused by polyfill docs and still getting following error: only one instance of babel-polyfill is allowed My webpack.config in short: entry1: ['babel-polyfill', 'homepage.js'], entry2: ['babel-polyfill', 'not-homepage.js'], entry3: ['babel-polyfill', 'contacts.js'] You are getting the error because you are calling multiple instances of the babel-polyfill. You can choose any of the two option, but not both. If you use webpack, don't put

Apologize in advance for lengthy post. I am trying to understand array reduce polyfill provided by MDN. I could not understand some lines in the polyfill can you explain it please. Below is the code if (!Array.prototype.reduce) { Object.defineProperty(Array.prototype, 'reduce', { value: function(callback /*, initialValue*/) { if (this === null) { throw new TypeError( 'Array.prototype.reduce ' + 'called on null or undefined' ); } if (typeof callback !== 'function') { throw new TypeError( callback + ' is not a function'); } // 1. Let O be ? ToObject(this value). var o = Object(this); // 2. Let

I just started to play around with Angular2, and ran into a weird component file extension problem: Let's use the 5 minutes quickstart demo from angular.io (I'll reproduce the code here for reference). File structure angular2-quickstart |- app | |- app.component.ts | |- boot.ts | |- index.html |- package.json |- tsconfig.json package.json { "name": "angular2-quickstart", "version": "1.0.0", "scripts": { "tsc": "tsc", "tsc:w": "tsc -w", "lite": "lite-server", "start": "concurrent \"npm run tsc:w\" \"npm run lite\" " }, "license": "ISC", "dependencies": { "angular2": "2.0.0-beta.0", "systemjs":