use warnings;
use Data::Dumper;

my @things_to_sort = (
                   { author => 'bart', title => 'skateboarding' },
                   { author => 'lisa', title => 'postmodernism' },
                   { author => 'marge', title => 'hairstyles' },
                   { author => 'lisa', title => 'THIS BOOK FIRST' },
                   { author => 'homer', title => 'donuts' },
                   { author => 'bart', title => 'coolness' }
                  );

my $author = '';
my @sort = 
  map { $_->[0] }
  sort { 
    $b->[1] <=> $a->[1] 
          ||
    $a->[0]->{author} cmp $b->[0]->{author}
          ||
    $a->[0]->{title} cmp $b->[0]->{title}
  } map { 
        [ 
          $_->[0], 
          $_->[0]->{author} eq $author ? $_->[1] + 2 
                                       : $_->[1] 
        ] 
      } map { 
            [
              $_, 
              $_->{title} eq 'THIS BOOK FIRST' 
                          ? ($author = $_->{author}) && 4 
                          : 0 
            ] 
            } @things_to_sort;

print Dumper \@sort
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#!/usr/bin/perl
use strict;
use warnings;
print TestSub();
print TestSub();
######################################
sub TestSub {
######################################
  open THIS,'>', \my $variable || die $!;
  print THIS "fooo\n" || die $!;
  close(THIS) || die $!;
  return $variable;
} #TestSub

__END__
fooo
Use of uninitialized value in open at ./foo.pl line 18.
fooo
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#!/usr/bin/perl
use strict;
use warnings;

for  (1 .. 4 ){
  open THIS,'>',\my $variable || die $!;
  print THIS "$_\n" || die $!;
  close(THIS) || die $!;
  print $variable || die $!;
};
__END__
1
Use of uninitialized value in open at ./foo.pl line 6.
2
Use of uninitialized value in open at ./foo.pl line 6.
3
Use of uninitialized value in open at ./foo.pl line 6.
4
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