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Introducing Code Hinting for Regular Expressions

It's been a long time in the making but code hinting is here, and I'm pretty excited about it.

Regex Code Hinting

I've created a short code hinting demo that shows it off a bit. This feature is available only to licensed users. If you're a licensed user and you open up the tester now you'll see hints appear as you start typing an open parenthesis "(", bracket "[" or brace "{".

I took a lot of inspiration from Intellisense. In particular, I based my design off of the Intellisense in Expression Blend. I like the look & feel of Expression Blend. But the regular expression language is so different than anything Intellisense is used for. So functionality-wise I was on my own.

I knew one thing I didn't want. I didn't want the code hinting to aggressively autocomplete. In other words, Intellisense in Visual Studio will sometimes autocomplete whatever you're typing at the time, sometimes adding code that you don't even want. That's a side effect of their complex algorithm that's normally pretty good. However, the regular expression syntax is tricky. And I have this theory. Most people can't write regular expressions as quickly and easily as .NET. So attempting aggressive auto-completion doesn't make much sense when the user may not know what they're looking for until they see it in the description. I fear that if Regex Hero tries too hard to predict what you're going to type before you type it then it'll inevitably make mistakes.

So I've made it impossible for the code hinting to do anything you don't want it to. You literally have to select the pattern from the list to add it to your regular expression. You can do that either by using the arrow keys to move to it and hitting enter or tab to select it, or by double clicking the pattern. I think this still makes the code hinting easy to use, but without all the fuss of accidental code modification. In my humble opinion, the end result is pretty awesome. It's a beautiful addition that allows you to be even more productive. And if it saves you from having to look up something in the reference then I've done my job.

I still want to add a few patterns to the mix and make it work with replacement patterns as well. But for now I think it's ready for primetime and I'd love to hear your thoughts.


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