#!/usr/bin/perl
my %h;
my $val = $h{x}{y};
use Data::Dumper;
print Dumper \%h;

##</code><code>##

$VAR1 = {
          'x' => {}
        };

##</code><code>##

#!/usr/bin/perl
my %h;
%{$h{x}};
use Data::Dumper;
print Dumper \%h;

##</code><code>##

$VAR1 = {};

##</code><code>##

#!/usr/bin/perl -w 
use strict;
my %h;
keys %{$h{x}};
use Data::Dumper;
print Dumper \%h;

##</code><code>##

$VAR1 = {
          'x' => {}
        };