Regex: Matching against groups in different order without repeating the group

Posted by Jimmy on Stack Overflow See other posts from Stack Overflow or by Jimmy
Published on 2010-04-08T00:48:46Z Indexed on 2010/04/08 0:53 UTC
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Let's say I have two strings like this:

XABY
XBAY

A simple regex that matches both would go like this:

X(AB|BA)Y

However, I have a case where A and B are complicated strings, and I'm looking for a way to avoid having to specify each of them twice (on each side of the |). Is there a way to do this (that presumably is simpler than having to specify them twice)?

Thanks

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