I'm sure someone will post an efficient regex, but in the meantime you can try this. Still a bit ugly, lines are joined then split on the HR tags.

YuckFoo


#!/usr/bin/perl

   use strict;

   my ($line, @keep);

   for $line ((split(/<HR>\s+/s, join('', (<DATA>))))) {
      if ($line =~ m{\d+\s+is\s+good}) { push (@keep, $line); }
   }

   for $line (@keep) { print "$line\n"; }

__DATA__
<HR>
1 is good<BR>
useless data<BR>
useless data<BR>
useless data<BR>
useless data<BR>
<HR>
2 is not good <BR>
useless data<BR>
useless data<BR>
useless data<BR>
useless data<BR>
<HR>
3 is good<BR>
useless data<BR>
useless data<BR>
useless data<BR>
useless data<BR>
<HR>
4 is not good <BR>
useless data<BR>
useless data<BR>
useless data<BR>
useless data<BR>
<HR>

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In reply to Re: parsing with regex by YuckFoo
in thread parsing with regex by 2501

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