sorry to trouble you once more, i have changed my regex into:

$tekst=~/(\b\w{3}\b)(?=.*\b\1\b)/g

And it appears to be working. Can someone explain the look ahead assertion.The part:

 ?=.*\b\1\b

It seems to me this ought to be ?=\1.

I dont understand it like this. Thank you.

In reply to Re: regex backreference by Anonymous Monk
in thread regex backreference by Anonymous Monk

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