A regular expression (regex) is a pattern that can be used to match a string of text. They are a standard feature of many programming languages that are used for text-processing purposes (and they have the inconvenient habit of being implemented ever-so-slightly differently in different languages).
What is Kernow?
Kernow is an open source tool designed to make it faster and easier to repeatedly run transforms using Saxon.
It uses compiled stylesheets, multiple threads and caching resolvers to make the transforms run efficiently, and comboboxes that remember between runs to save your fingers having to retype paths. Kernow is runnable from Ant allowing it to slot into your build process, and its a high level API for Saxon making it very easy to run transforms from your own Java applications.