Code-Parsing Regular Expressions via Lighter.js

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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!

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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.

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