In theoretical computer science and formal language theory, a regular expression (abbreviated regex or regexp) is a sequence of characters that forms a search pattern, mainly for use in pattern matching with strings, or string matching, i.e. “find and replace”-like operations. The concept arose in the 1950s, when the American mathematician Stephen Kleene formalized the description of a regular language, and came into common use with the Unix text processing utilities ed, an editor, and grep (global regular expression print), a filter.
There are many tools to build and test regular expressions. The purpose here is not to draw up a complete list of such tools, but to share the best of the ones I know, ordered by preference (ie completely subjective!)
- Regex Hero
Rubular is a Ruby-based regular expression editor. It’s a handy way to test regular expressions as you write them.
Definitely my favorite!
A tool for generating and testing regular expressions.
Regex Hero runs directly off of the Regex class library inside Silverlight. I will say that Silverlight is missing the RegexOptions.
Online Regular Expression Tester that supports PHP, Ruby, Python, Javasript. Real-time result and permalink to share regex.