#!/usr/bin/perl -w

package Tie::Hash::Test;
use Tie::Hash;
use Attribute::Handlers autotie => { __CALLER__::Test => __PACKAGE__ };
use vars qw(@ISA);
@ISA = 'Tie::StdHash';
sub TIEHASH {
  my $class = shift;

  my %self;
  @self{@_} = (undef) x @_;

  bless \%self, $class;
}

package main;

my %hash : Test('one', 'two', 'three');

print join(':', keys %hash), "\n";