Hi Monks,

I've recently seen this kind of code written by an experience Perler.

perl -ne 'print if s/.*?(?=abc)//...0' inputfile

[download]

I think I understand all of it, except the "...0" part.

The code runs without syntax error, and if I change the "...0" to "....0" or "..0" or ".0" or "" (i.e. remove it), then it seems to give the same output.

What is this "...0" about and why is it that changing it to "....0", "..0", ".0" and "" give the same output?

Thanks.

In reply to What's the "...0" mean? by tel2

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