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Message-ID: <1653533.WIYo4VKPqX@PointedEars.de>
From: Thomas 'PointedEars' Lahn <PointedEars@web.de>
Reply-To: Thomas 'PointedEars' Lahn <usenet@PointedEars.de>
Organization: PointedEars Software (PES)
Date: Tue, 22 Jan 2013 18:34:06 +0100
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Subject: Re: RegExp debugging tool
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Asen Bozhilov wrote:

> I developed tool which traces the steps needed by JS regular
> expression to find matching substring or fail. It shows step by steps
> how the regex is applying on the input data. If the engine performs
> step backward aka backtracking, the tool indicates for that. That was
> primary goal. I was inspired by RegexBuddy and wanted such tool, but
> online. I used BESEN's debug mode of RegExp.
> 
> <URL:http://www.regexter.com/>
> 
> The tool is still in beta and any suggestions or bug reports are
> welcome.

I do not understand why “f*” would first try to match “f” instead of “fff” 
in “fff”.  ISTM that efficiency of the parser could be greatly improved if 
the latter was the case.  Is this due to BESEN?

I do not know RegexBuddy, but for visualization you should look into Bastian 
Bergerhoff's QuickREx [1].  I have always found the highlighting of 
subexpressions and matching substrings to be useful in Eclipse (and 
fortunately that extension is still working even in Eclipse 4.3 [Kepler] M4; 
the only thing it is lacking is support for ECMAScript RE).

> Also I think the FAQ of clj should have a link to this tool.

Noted for discussion.

[1]
<http://www.bastian-bergerhoff.com/eclipse/features/web/QuickREx/toc.html>

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PointedEars

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