One of the projects I am working on involves screen scraping information off various web sites. Shortly after I started, I quickly learnt that any attempts towards serious screen scraping will required the use of regular expressions to detect patterns in the HTML source. And so began my (short lived) search for a tool to help me build and test regular expressions - thanks to Expresso 3.0 by Ultrapico.
Expresso is by far the best free regular expression tool I have used to date. It has the following features that I consider very important in a regular expression tool (and much, much more)
- Expression builder (Expresso enables you to create regular expressions without having to remember an arcane syntax.)
- Expression library (library of common and frequently used expressions) and the ability add to it.
- Expression analyzer (Complex regular expressions can be notoriously obtuse to read)
- Expression validator
- Grouping of matches showing captured groups.
But the wow factor really kicked in when I saw that Expresso has many more features like exporting results, partial matching, performance testing, character class subtraction etc.