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
    Write Better JavaScript with Promises

    You've probably heard the talk around the water cooler about how promises are the future. All of the cool kids are using them, but you don't see what makes them so special. Can't you just use a callback? What's the big deal? In this article, we'll...

  • By
    An Interview with Eric Meyer

    Your early CSS books were instrumental in pushing my love for front end technologies. What was it about CSS that you fell in love with and drove you to write about it? At first blush, it was the simplicity of it as compared to the table-and-spacer...

Incredible Demos

  • By
    Spyjax:  Ajax For Evil Using Dojo

    The idea of Spyjax is nothing new. In pasts posts I've covered how you can spy on your user's history with both MooTools and jQuery. Today we'll cover how to check user history using the Dojo Toolkit. The HTML For the sake of this...

  • By
    dwProgressBar v2:  Stepping and Events

    dwProgressBar was a huge hit when it debuted. For those of you who didn't catch my first post, dwProgressBar is a MooTools 1.2-based progress bar which allows for as much flexibility as possible. Every piece of dwProgressBar can be controlled by CSS...

Discussion

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