I don't know if this adds anything valuable to this thread, but I've played around quite a bit with code eval expressions. Here's a trick that allows you to do modification without using substitution:

perl -wMstrict -E 'for(1..3){/2(?{$_ += 10})/;say}'
1
12
3

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In reply to Re: Value of $_ inside a regex by stevieb
in thread Value of $_ inside a regex by Athanasius

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