LC crossai-2033

Incorrect ES5 fallbacks

Over the weekend I implemented a few Array methods in plain JavaScript to avoid recently patched Rhino bugs. That got my thinking about ES5 fallback implementations in various JavaScript libs/frameworks/transpilers. I decided to compile a not-so-complete list of ES5 related discrepancies found in many of them. Differences in native vs. fallback implementations create cross-browser inconsistencies and increase the chance of usage errors. I hope this post will raise awareness of just how hard it is to follow spec (during my research I found a couple of issues in my own projects too). All library developers should to take a closer look at their code and make the small changes needed to follow the specification (especially if your code forks for native methods).

Common Issues

Most implementations suffer from the foll

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	copyright 2008 Thomas Frank

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	* Preload images, CSS and JavaScript files without executing them
	* Script by Stoyan Stefanov – http://www.phpied.com/preload-cssjavascript-without-execution/
	* Slightly rewritten by Mathias Bynens – http://mathiasbynens.be/
	* Demo: http://mathiasbynens.be/demo/javascript-preload
	*/

	function preload(arr) {
	var i = arr.length,

	<!doctype html>
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