Hi, I'm sorry to bother. I was using the splitRegex function http://cvs.haskell.org/Hugs/pages/libraries/base/Text-Regex.html#t%3ARegex and it enters an infinite loop when I enter the command (splitRegex (mkRegex "") "hi") I apologize if this is not a bug or if it's the wrong place to submit it. Best regards, damian.