Code-Parsing Regular Expressions via Lighter.js

By  on  

Perfecting a regular expression can take a lot of time and testing but once achieved can be a absolutely golden. While looking through the source code of MooTools syntax highlighter Lighter.js I stumbled upon a few code-parsing regular expressions that you might be interested in.

The JavaScript

	// Matches a C style single-line comment.
	slashComments: /(?:^|[^\\])\/\/.*$/gm,
	
	// Matches a Perl style single-line comment.
	poundComments: /#.*$/gm,
	
	// Matches a C style multi-line comment.
	multiComments: /\/\*[\s\S]*?\*\//gm,
	
	// Matches a string enclosed by single quotes.
	aposStrings:   /'[^'\\]*(?:\\.[^'\\]*)*'/gm, 
	
	// Matches a string enclosed by double quotes.
	quotedStrings: /"[^"\\]*(?:\\.[^"\\]*)*"/gm, 
	
	// Matches both.
	strings:       /'[^'\\]*(?:\\.[^'\\]*)*'|"[^"\\]*(?:\\.[^"\\]*)*"/gm,
	
	// Matches a property: .property style.
	properties:    /\.([\w]+)\s*/gi,   
	
	// Matches a method call: .methodName() style.
	methodCalls:   /\.([\w]+)\s*\(/gm, 
	
	// Matches a function call: functionName() style.
	functionCalls: /\b([\w]+)\s*\(/gm,   
	
	// Matches any of the common brackets.
	brackets:      /\{|\}|\(|\)|\[|\]/g, 
	
	// Matches integers, decimals, hexadecimals.
	numbers:       /\b((?:(\d+)?\.)?[0-9]+|0x[0-9A-F]+)\b/gi 

Regular expressions can look heinous so I apologize to anyone whose brains imploded after looking at the above hieroglyphics text. Have useful regular expressions you use often? Share them!

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
    39 Shirts – Leaving Mozilla

    In 2001 I had just graduated from a small town high school and headed off to a small town college. I found myself in the quaint computer lab where the substandard computers featured two browsers: Internet Explorer and Mozilla. It was this lab where I fell...

Incredible Demos

  • By
    Control Element Outline Position with outline-offset

    I was recently working on a project which featured tables that were keyboard navigable so obviously using cell outlining via traditional tabIndex=0 and element outlines was a big part of allowing the user navigate quickly and intelligently. Unfortunately I ran into a Firefox 3.6 bug...

  • By
    Record Text Selections Using MooTools or jQuery AJAX

    One technique I'm seeing more and more these days (CNNSI.com, for example) is AJAX recording of selected text. It makes sense -- if you detect users selecting the terms over and over again, you can probably assume your visitors are searching that term on Google...

Discussion

  1. David: very interesting, could you provide examples for each expression? ty so much!

  2. That’s pretty neat

    I’ve always used http://www.gskinner.com/RegExr/ to text my RegExp

  3. Well, im not a veteran programmer but i did a noobMatcher to test my regExp hehe

    http://vrs.host56.com/noobMatcher/

  4. Thanks for this Tutorial. Can u provide Demo for this.

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