Top of the mornin!

Ive been hacking around all night and I have gargled some code which is confusing me. 

perl -wle '$_="a"x20;s/(?{print "${^O}rules".-"${0}macs"})//g'|wc -l

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I was obfuscating sorry.

the idea is that no matter what you change the length of $_ to, it is always going to run the print command 2x the number plus two. I am speculating that this number may change on different platforms. But anyways. What is the logic here? What is the regex doing to come to that magical number of executes?

In reply to (${code}) Regex - Iteration by zer

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