I think primes is really cool! I would like to fully understand how it works and I have 2 questions about the second part of the regex: 1. why isn't (xx+) greedy? I mean why doesn't it match the whole string of x in $_? 2. I thought it was possible substitute \1 with $1: ^(xx+)$1+$, but this regex doesn't work correctly. why? TIA for any explanation. marcos

In reply to RE: RE: RE: Primes by marcos
in thread Primes by Mo

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