What testing tool do you use most often when testing new regexes? Is it a desktop or website? Why do you like it better than other tool?  Are there any issues with it?

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Michael

"In theory, theory and practice are the same. In practice, they are not."
Albert Einstein

I use the Regulator for most of my testing. 
PROS:
Free
Modifiable interface.  You can dock or undock sections as need.
You can browse for and open files that contain your data.
You can highlight portions of a pattern and execute just that part.  Good for debugging large patterns.
You can match, replace and split text. The results are shown in a separate window.
Match results are in a tree structure with also show the groups and captures.
Can stop runaway code from a bad pattern.
Can search for and download patterns from the regexlib.
Can upload new patterns to the regexlib.
Will generate code template with your pattern.

CONs
Intelli-sense gets in the way at time. probably good for people new to regex but slows you down if you try to type in a pattern without using it.  But it can be turned off.
Buffer problems. Saving a pattern or turning on or off a option will somethings delete the last character typed. I have to highlight the entire pattern before saving. or type an extra character before changing the options
Can't change the font used for the match results so some Unicode characters are not viewable.


Not really a con but regex engine is for .Net, so patterns are not guarenteed to work with Scripting engines (VBScript/JScript/Javascript).

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Michael

"In theory, theory and practice are the same. In practice, they are not."
Albert Einstein

Both Expresso and the Regulator are more intricate than Chris Sells's Regex Designer, but Chris color codes the captures! Nice if you're in a hurry! In fact, a recent thread documents problems resulting from Expresso's lack of a good way to display 0-length matches (Chris interpolates a little [] in a different color) I like Expresso's way of breaking down expressions, too. There's a nicely-designed tool for Python called Kiki, which unfortunately doesn't do replacement, but Python is an excellent scripting language, which I would certainly prefer to VBScript. Kiki also color-codes matches. There is no really professional-looking GUI front-end around Perl's regex engine, which is a real shame, Regex Coach notwithstanding.

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"Some day, and that day may never come, I will call upon you to do a service for me." — Don Vito Corleone

The Regex Coach is a good testing tool that uses a Perl-compatible engine.  The it has some nice features. One being it's real-time.  patterns are evaluated as soon as you type them in. One of the nice features is that you can step thru the execution of a pattern which is great for debugging.  It's a good tool for regex beginners because the step feature allows you to see how the engine is actually evaluating as opposed to how you thought it would.  There are a couple of cons against it. One it only returns the first match.  So you can't really test multiple values that vary slightly in your source with one pass.  However that really only applies to matching.  Replace and Split work against the entire document.  Second it doesn't  support all the advanced regex features.
The real strength of this application is it's analyst features. Aside from the step thru you can also generate a tree of all the paths the regex engine pursues to evealuate input.

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Michael

"In theory, theory and practice are the same. In practice, they are not."
Albert Einstein

It's not free ($29.95), but I couldn't live without RegexBuddy (http://www.regexbuddy.com/)...absolutely wonderful software. The guy that makes it also has a pretty good regex tutorial site at http://www.regular-expressions.info/

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