Think lines and grab just those you want. Consider:

use strict;
use warnings;

my $fc = <<FC;
#4 
r0 !
r1 !
r2 !
#5
r3 !
r4 !
r5 !
FC

print "$1\n$2\n" while $fc =~ /^(#\d+).*?^.*?^(.*?)$/gms;

[download]

Prints:

#4
r0 !
#5
r3 !

[download]

Note the regex switches - g to match multiple times, s to let . match new line characters, and m to perform a multi-line match which allows the internal ^ and $ matches to work.

True laziness is hard work

In reply to Re: substitute instead global matching for nested matches by GrandFather
in thread substitute instead global matching for nested matches by utku

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