How do you debug a regex?

debugging, pcre, regex

Solution

You buy RegexBuddy and use its built in debug feature. If you work with regexes more than twice a year, you will make this money back in time saved in no time. RegexBuddy will also help you to create simple and complex regular expressions, and even generate the code for you in a variety of languages.

Also, according to the developer, this tool runs nearly flawlessly on Linux when used with WINE.

Problem

Regular expressions can become quite complex. The lack of white space makes them difficult to read. I can't step though a regular expression with a debugger. So how do experts debug complex regular expressions?

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