What you and I and, it seems, everyone else are missing is a clear understanding of BernieC's requirements.

What I understand (or imagine I understand) is that one must detect repetition only of a set of characters given in a "template" string. So if the template is 'abc', the string 'xxxabcxxx' has no repetition and the string 'aba' does. See Re^3: Nonrepeating characters in an RE (updated) and Re: Nonrepeating characters in an RE (updated) for my take on solutions to what I imagine BernieC's requirements to be.

Give a man a fish:  <%-{-{-{-<

In reply to Re^2: Nonrepeating characters in an RE by AnomalousMonk
in thread Nonrepeating characters in an RE by BernieC

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