Standard regex symbols don't seem to behave correctly. Is there documentation on this?
We don't tend to document regex itself, since there are several excellent sites (like this one) which do a far more extensive job than we would. We do have some basic hints in the group builder, if you hover over the "?" icon (as shown below), that are usually sufficient for 'casual' Regex users.
I've also had occasion to make quite complicated regex strings involving 'look back' and so on which have been fine. That's not to say you might have uncovered something though!
Could you post back with the regex you are trying to use, and the description of what you want to achieve with it?
We were provided several regular expressions from another team that didn't return any results, but after adding .* to the end of the expression they now work.
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