I believe many have touched on the fact that infinite possibilities exist for any given situation unless you already had some notion of what you expected in the first place. I use the following tool to help with tricky regex expressions, not because I can't do them myself, but rather to help speed up the process. http://weitz.de/regex-coach/

In reply to Re: Reverse engineering regular expressions by onegative
in thread Reverse engineering regular expressions by paulski

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