Perl: dereferencing an hash of hash of hashes

Question

consider the sample code:

$VAR1 = {
      'en' => {
              'new' => {
                       'style' => 'defaultCaption',
                       'tts:fontStyle' => 'bold',
                       'id' => 'new'
                     },
              'defaultCaption' => {
                                  'tts:textAlign' => 'left',
                                  'tts:fontWeight' => 'normal',
                                  'tts:color' => 'white',

                                }
            },
      'es' => {
              'defaultSpeaker' => {
                                  'tts:textAlign' => 'left',
                                  'tts:fontWeight' => 'normal',

                                },
              'new' => {
                       'style' => 'defaultCaption',
                       'tts:fontStyle' => 'bold',
                       'id' => 'new'
                     },
              'defaultCaption' => {
                                  'tts:textAlign' => 'left',
                                  'tts:fontWeight' => 'normal',

                                }
            }
    };

i return it as reference, return \%hash

how do i dereference this?

Answer 1

%$hash. See http://perldoc.perl.org/perlreftut.html for more information.

If your hash is returned by a function call, you can do either:

my $hash_ref = function_call();
for my $key (keys %$hashref) { ...  # etc: use %$hashref to dereference

Or:

my %hash = %{ function_call() };   # dereference immediately

To access values within your hash, you can use the -> operator.

$hash->{en};  # returns hashref { new => { ... }. defaultCaption => { ... } }
$hash->{en}->{new};     # returns hashref { style => '...', ... }
$hash->{en}{new};       # shorthand for above
%{ $hash->{en}{new} };  # dereference
$hash->{en}{new}{style};  # returns 'defaultCaption' as string

Answer 2

try something like below, might be helpful for you:

my %hash = %{ $VAR1};
        foreach my $level1 ( keys %hash) {
            my %hoh = %{$hash{$level1}};
            print"$level1\n";
            foreach my $level2 (keys %hoh ) {
               my %hohoh = %{$hoh{$level2}};
               print"$level2\n";
               foreach my $level3 (keys %hohoh ) {
                        print"$level3, $hohoh{$level3}\n";
                }
             }
        }

Moreover, if you want to access the specific key, you can do it like

my $test = $VAR1->{es}->{new}->{id};