Use YAML. Here are just some highlights. Use YAML. It obviates the need to reinvent the wheel. Use YAML. It's easy.

NOTES ON DATASTRUCTURE The easiest way to visualize and understand the data structure: it is just like an Excel 'spreadhsheet workbook'. Each 'worksheet' represents an element of your model. Each worksheet holds one and only one 'table'.
You can create any level of heirarchy with this model simply by adding 'links'. You can easily translate this model in and out of a database because everything is organized as tables. You can easily translate this model into a directed graph. You can easily translate this model into just about *anything* you can represent digitally.

NOTES ON FIELDS

• name : the 'database-friendly' version of the name
• caption : the 'user-input-form-friendly' version of the name

ADDITIONAL CONSIDERATIONS

• you can easily create links and multiple nested levels with YAML without modifying the simple datastructure

The Code

### INIT script
    use strict;
    use warnings;
    use YAML;
    use Data::Dumper;
    my  $dataroot   = YAML::Load(join "", (<DATA>));

    print $dataroot->{person}[0]{fname};
    print "\n------------------\n";

    print $dataroot->{person}[0]{lname};
    print "\n------------------\n";

    print $dataroot->{person}[0]{city}{caption};
    print "\n------------------\n";

    print   Data::Dumper->Dump([$dataroot], [qw(dataroot)]);
    print "\n------------------\n";

1;
__END__
country:
  - &IDxCountryA
    name:       CountryA
    caption:    Country Alpha

  - &IDxCountryB
    name:       CountryB
    caption:    La Cuidad Del B

  - &IDxCountryC
    name:       CountryC
    caption:    United C Emirates

state:
  - &IDxStateWashatovia
    name:       washatovia
    caption:    Washatovia
    country:    *IDxCountryC

  - name:       nervada_dc
    caption:    Nervada D.C.
    country:    *IDxCountryC

city:
  - &IDxCityParisis
    name:       Parisis
    caption:    Parisis

person:
  - fname:      Samir
    lname:      Krishnamurty
    city:       *IDxCityParisis
    state:      *IDxStateWashatovia
    country:    *IDxCountryC
[download]