my $this = { 'name' => 'alex' };
my $that = \%{ $this };
# now i thought that $that would be an independent copy, but:
$that->{'name'} = 'madonna';
print $this->{'name'}; 
# oh no! i'm madonna! they both referenced the same thing

##</code><code>##

my $this = { 'name' => 'alex' };
my %that = %{ $this };
my $that = \%that;
# now $that really is an independent copy, and:
$that->{'name'} = 'madonna';
print $this->{'name'}; #alex
# phew! I'm still me!