Hint : it's much easier to traverse deep data structure when iterating over values instead of keys, especially if you never need the keys.

Please note my naming convention using trailing h_ and a_ to denote hash refs and array refs.

i.e. h_codes -> h_planet -> a_aa see included dump

Like this it's obvious when to use @$a_ and %$h_ for dereferencing ...

use strict;
use warnings;
use Data::Dump qw /pp dd/;


my %aas = (
           'serine'  => ['TCA', 'TCC', 'TCG', 'TCT'],
           'proline' => ['CCA', 'CCC', 'CCG', 'CCT']
          );

my %codes;
$codes{'earth'} = \%aas;
$codes{'mars'} = {
                  'serine'  => ['QWZ', 'QWX', 'QWW'],
                  'proline' => ['ZXZ', 'ZXX', 'ZXQ', 'ZXW']
                 };


dd \%codes;                             # dump for clarity

base_code (\%codes);


sub base_code  {
   my ($h_codes) = @_;
   for my $h_planet (values %$h_codes) {
      for my $a_aa (values  %$h_planet) { #
         for my $codon ( @$a_aa ) {
            print $codon, "\n";
         }
      }
   }
}

[download]

{
  earth => {
             proline => ["CCA", "CCC", "CCG", "CCT"],
             serine  => ["TCA", "TCC", "TCG", "TCT"],
           },
  mars  => {
             proline => ["ZXZ", "ZXX", "ZXQ", "ZXW"],
             serine  => ["QWZ", "QWX", "QWW"],
           },
}
TCA
TCC
TCG
TCT
CCA
CCC
CCG
CCT
QWZ
QWX
QWW
ZXZ
ZXX
ZXQ
ZXW

[download]

Cheers Rolf
(addicted to the Perl Programming Language and ☆☆☆☆ :)
Je suis Charlie!

In reply to Re: printing complex data structures (values) by LanX
in thread printing complex data structures by ic23oluk

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