This small modification makes your code work: 
foreach my $line (split /^/, $text) {
    print $line;
    my $separator_printed = 0;
    foreach ($line =~ m/\[.*?\]\[(.*?)\]/g) {
        my $link_number = $_;
         $separator_printed++ or print "\n";
        print grep(/(\[$link_number\]\:.*)/, @url_list);
        print "\n";
    }
}

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        What is the sound of Perl? Is it not the sound of a wall that people have stopped banging their heads against?
              -Larry Wall, 1992

In reply to Re: Preventing Blank Lines Between Printed Array Elements by NetWallah
in thread Preventing Blank Lines Between Printed Array Elements by immamanatee

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