I think you've rather shot yourself in the foot with that data structure. It really makes it difficult to access the second level categories that are children of a particular category.

Personally I'd use the flexibility of Perl data structures to my advantage and build a structure like this:

#!/usr/local/bin/perl

use strict;
use warnings;

my %category_hash =
  (
   1 => {
         name => 'whatever',
         children => {
           2 => {
                 name => 'something',
                 children => {
                   3 => { name => 'another subcategory' }
                 }
                }
          }
         },
    4 => { name => 'something else' }
  );

[download]

You can then display the structure with code like this: 

show(\%category_hash, 0);

sub show {
  my ($hash, $lvl) = @_;

  my $prefix = '  ' x $lvl;

  foreach (sort keys %$hash) {
    print "$prefix$_ : $hash->{$_}{name}\n";
    show($hash->{$_}{children}, ++$lvl)
      if exists $hash->{$_}{children};
  }
}

[download]

But you should also look at the Tree modules from CPAN.

--
<http://www.dave.org.uk>

"The first rule of Perl club is you do not talk about Perl club."
-- Chip Salzenberg

In reply to Re: Looping through Multi Dimensional Hashes by davorg
in thread Looping through Multi Dimensional Hashes by CodeJunkie

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