One thought on initialization: To improve readability and perhaps simplify maintenance, I would be inclined to store the list of information in a __DATA__ section and create the hash dynamically, something like this: 
my %country_hash;

chomp (my @data_rows = <DATA>);
foreach my $this_country (@data_rows) {
  my $country_code = substr($this_country,0,2);
  my $country_name = substr($this_country,3);
  $country_hash{$country_code} = $country_hash{$country_name} = $this_
+country;
}

# ... your tie code ...
__DATA__
AF Afghanistan
AL Albania
DZ Algeria
.....

[download]

In my eyes this would be easier to read and maintain. Also, special chars like the apostrophe Cote d'Ivoire no longer require escaping.

In reply to Re: Validate Country by ISO 3166 data by seattlejohn
in thread Validate Country by ISO 3166 data by shotgunefx

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