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Fixed Bugs With Saving Locally, The Analyzer, And a New Recommendation Engine

Bug Fixes

Today's update takes care of a couple bugs:
  1. Saving locally to your computer with Regex Hero Professional would fail with certain special characters.
  2. The analyzer would fail in rare situations involving very complex character classes.

Recommendation Engine

And lastly, I've included a beta version of a new recommendation engine. This is available only to users of Regex Hero Professional. The recommendations that are produced are all related to performance. And the type of recommendations that are produced are limited at this point. Often you'll see the message, "No recommendations found." This is something I intend to continue to work on and improve in the upcoming months.

Here are the possible recommendations I've included so far:

  1. IgnoreCase is not needed and slows down processing. Please disable it. This one determines when the IgnoreCase flag isn't doing anything for you. For example, \w matches word characters and it's case insensitive, so adding the IgnoreCase just for that would be pointless and would slow down the regular expression.
  2. Redundant quantifiers may be slow. Please remove the first quantifier. This identifies situations such as x+x+. The '+' quantifier used back to back on the same character does nothing but make the regular expression much slower than it should be. This can be simplified to xx+.
  3. Alternations are slow. Please change to a character class. This identifies single character alternations such as a|b|c. It is slightly more efficient to use [abc] instead.
  4. Do not repeat 3 or more characters. Use a numbered quantifier instead. This is a minor one, but rather than \w\w\w you can use \w{3} and see slightly improved performance. The performance gains are greater the more characters you're dealing with.
  5. Do not perform case insensitive matching with a character class. Use the IgnoreCase option instead. In some old regex implementations, there was no IgnoreCase flag. So the workaround would be to explicitly include both cases, e.g. [Aa][Bb][Cc]. But there's no need for that anymore, and it's more efficient to just use the IgnoreCase option.
There will be more rules coming, as well as improvements to the intelligence and guidance behind these existing rules. But the big feature to come next is to actually allow you to simply click a button to fix the problem.


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