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
    Being a Dev Dad

    I get asked loads of questions every day but I'm always surprised that they're rarely questions about code or even tech -- many of the questions I get are more about non-dev stuff like what my office is like, what software I use, and oftentimes...

  • By
    CSS Filters

    CSS filter support recently landed within WebKit nightlies. CSS filters provide a method for modifying the rendering of a basic DOM element, image, or video. CSS filters allow for blurring, warping, and modifying the color intensity of elements. Let's have...

Incredible Demos

  • By
    Create Keyboard Shortcuts with Mousetrap

    Some of the finest parts of web apps are hidden in the little things.  These "small details" can often add up to big, big gains.  One of those small gains can be found in keyboard shortcuts.  Awesome web apps like Gmail and GitHub use loads of...

  • By
    CSS Vertical Center with Flexbox

    I'm 31 years old and feel like I've been in the web development game for centuries.  We knew forever that layouts in CSS were a nightmare and we all considered flexbox our savior.  Whether it turns out that way remains to be seen but flexbox does easily...

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!