pyscripter 689 Posted November 25, 2018 One of the improvements in Delphi Rio is the upgrade of PCRE to version 8.42 and more importantly the inclusion of UTF-16 support on Windows. What this means is that Delphi strings are no longer converted to UTF-8 and back when using Regular Expressions. This blog post describes a benchmark of various regular expression options. I wanted to see the impact of the Rio improvements and here are the results. The results below use the test suite of the above mentioned article. Delphi 10.2: Total Time: 12639.00 ms Delphi 10.3: Total Time: 10614.00 ms (about 17% faster) Further improvement can be achieved by using PCRE Study. Fir a bit of extra compile time you have significant execution benefits. You need a class helper to use Study with TRegEx: type TRegExHelper = record helper for TRegEx public procedure Study; end; procedure TRegExHelper.Study; begin with Self do FRegEx.Study; end; You can call study after TRegEx,Create. Here are the results with Study. Delphi 10.2: Total Time: 9863.00 ms Delphi 10.3: Total Time: 7895.00 ms (about 20% faster) 2 2 Share this post Link to post