http://www.perlmonks.org?node_id=1016410


in reply to regex on previous lines

This is, or could be, quite easy.   First, read (or otherwise get ...) all three strings.   (Die horribly if you can’t...)   Simply put them into three variables ... let’s call ’em $x, $y, $z.

I said it would be easy....

if ($y ~= /regex2/) { if ($y =~ /regex1/) { ... feel free ... } }

Perhaps you would instead decide to keep the three strings in an array.   In that case, $x would be $array[0] and so-on.   If you want to maintain a three-string “window” on a file, functions such as length(), push, shift will come in handy.

If you will please give us more details about exactly what you’re up to, The Monks will be pleased to help you more.   “Ask a more-precise question, get a more-precise answer, and, hey, both of us can call it a day and go to the pub.”