The new RegularExpressionsCore unit in Delphi XE is based on the PerlRegEx unit that I wrote many years ago. Since I donated full rights to a copy rather than full rights to the original, I can continue to make my version of TPerlRegEx available to people using older versions of Delphi. I did make a few changes to the code to modernize it a bit prior to donating a copy to Embarcadero. The latest TPerlRegEx includes those changes. This allows you to use the same regex-based code using the RegularExpressionsCore unit in Delphi XE, and the PerlRegEx unit in Delphi 2010 and earlier.

If you’re writing new code using regular expressions in Delphi 2010 or earlier, I strongly recomment you use the new version of my PerlRegEx unit. If you later migrate your code to Delphi XE, all you have to do is replace PerlRegEx with RegularExrpessionsCore in the uses clause of your units.

If you have code written using an older version of TPerlRegEx that you want to migrate to the latest TPerlRegEx, you’ll need to take a few changes into account.

The original TPerlRegEx was developed when Borland’s goal was to have a component for everything on the component palette. So the old TPerlRegEx derives from TComponent, allowing you to put it on the component palette and drop it on a form.

The new TPerlRegEx derives from TObject. It can only be instantiated at runtime. If you want to migrate from an older version of TPerlRegEx to the latest TPerlRegEx, start with removing any TPerlRegEx components you may have placed on forms or data modules and instantiate the objects at runtime instead. When instantiating at runtime, you no longer need to pass an owner component to the Create() constructor. Simply remove the parameter.

Some of the property and method names in the original TPerlRegEx were a bit unwieldy. These have been renamed in the latest TPerlRegEx. Essentially, in all identifiers SubExpression was replaced with Group and MatchedExpression was replaced with Matched. Here is a complete list of the changed identifiers:

Download TPerlRegEx. Source is included under the MPL 1.1 license.