Okay, let me amend my comment. If you have a degree in CS, you're absolutely sure that you've understood all the caveats of the libraries you're using, and you

Okay, let me amend my comment. If you have a degree in CS, you're absolutely sure that you've understood all the caveats of the libraries you're using, and you limit your inputs so that the expected running time is under your target execution time, then you can avoid putting a timeout on your regex executions. In any other case, add a timeout.