>>How does the regex engine know that it matched $?

Hi.

I think engine doesn't know. It knows e.g. that it matched a zero-length branch once. And it cancels to match second time the same place in order to avoid eternal matching.
I believe you can get similar results with regexes like these: m/.|(?:)/gc, m/.|(?=)|(?:)/gc...

In reply to Re^3: perl indication of end of string already matched by rsFalse
in thread perl indication of end of string already matched by nachumk

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