Using Function.toString to Troubleshoot JavaScript Issues

By  on  

Sometimes JavaScript bugs can be the most frustrating damn things in the world. That problem is compounded when a JavaScript file is created from multiple files on the server side or you simply aren't familiar with some of the code used in a project (i.e. troubleshooting an issue with a JavaScript framework you aren't familiar with. Sometimes just identifying the code within a function is enough to point you in the correct direction. So to quickly check the code for a given function, I'll type into the console something like:

myProblemFunction.toString();

That would return something like:

function myProblemFunction() {
	/* bunch of code here */
	
	some.problem().code;
	
	/* bunch of code here */
}

Awesome. Now that I can get the function code at a glance, I can more easily browse through what could be causing the issue and see what needs to be changed. Usually any hint you can get toward finding where the issue resides is a big help!

Recent Features

  • By
    fetch API

    One of the worst kept secrets about AJAX on the web is that the underlying API for it, XMLHttpRequest, wasn't really made for what we've been using it for.  We've done well to create elegant APIs around XHR but we know we can do better.  Our effort to...

  • By
    CSS Animations Between Media Queries

    CSS animations are right up there with sliced bread. CSS animations are efficient because they can be hardware accelerated, they require no JavaScript overhead, and they are composed of very little CSS code. Quite often we add CSS transforms to elements via CSS during...

Incredible Demos

  • By
    WebKit Marquee CSS:  Bringin’ Sexy Back

    We all joke about the days of Web yesteryear.  You remember them:  stupid animated GIFs (flames and "coming soon" images, most notably), lame counters, guestbooks, applets, etc.  Another "feature" we thought we had gotten rid of was the marquee.  The marquee was a rudimentary, javascript-like...

  • By
    Fancy FAQs with jQuery Sliders

    Frequently asked questions can be super boring, right? They don't have to be! I've already shown you how to create fancy FAQs with MooTools -- here's how to create the same effect using jQuery. The HTML Simply a series of H3s and DIVs wrapper...

Discussion

    Wrap your code in <pre class="{language}"></pre> tags, link to a GitHub gist, JSFiddle fiddle, or CodePen pen to embed!