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
    Detect DOM Node Insertions with JavaScript and CSS Animations

    I work with an awesome cast of developers at Mozilla, and one of them in Daniel Buchner. Daniel's shared with me an awesome strategy for detecting when nodes have been injected into a parent node without using the deprecated DOM Events API.

  • By
    CSS @supports

    Feature detection via JavaScript is a client side best practice and for all the right reasons, but unfortunately that same functionality hasn't been available within CSS.  What we end up doing is repeating the same properties multiple times with each browser prefix.  Yuck.  Another thing we...

Incredible Demos

  • By
    Build a Calendar Using PHP, XHTML, and CSS

    One of the website features my customers love to provider their web users is an online dynamic calendar. An online calendar can be used for events, upcoming product specials, memos, and anything else you can think of. I've taken some time to completely...

  • By
    Build a Slick and Simple MooTools Accordion

    Last week I covered a smooth, subtle MooTools effect called Kwicks. Another great MooTools creation is the Accordion, which acts like...wait for it...an accordion! Now I've never been a huge Weird Al fan so this is as close to playing an accordion as...

Discussion

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