I assume that the pattern must repeat at least twice, otherwise, the full string is always the longest answer.

I wish that were the case. It mostly will be, but sometimes the string will consist of 1 complete and 1 partial rep.

But the partial rep at the end *will* exactly match the same number of characters at the beginning of the string, so it will always be possible to determine the rep.

But how to encode that in a regex or at least avoid a brute force chop and compare?

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In reply to Re^2: Finding repeat sequences. (only mostly regex) by BrowserUk
in thread Finding repeat sequences. by BrowserUk

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