package my::data;

use strict;
use warnings;

my $Config ={
# this would be loaded from a config.ini file
  root => {
    local => 'c:/local',
    remote => 'docroot',
  },
  category => {
    europe => 'europe.html',
    women  => 'women.html',
  },
};

sub Config{
  if (@_ == 4){
    $Config->{$_[1]}{$_[2]} = $_[3];
    return $_[3];
  }
  elsif (@_ == 3){
    if (exists $Config->{$_[1]}{$_[2]}){
      return $Config->{$_[1]}{$_[2]};
    }
    else{
      return;
    }
  }
  else{
    return;
  }
}

1;

##</code><code>##

use my::data;

##</code><code>##

$data = my::data->Config('root', 'local');

##</code><code>##

my::data->Config('root', 'local' => 'c:/local_path');