package Toy_Iterator;

use overload 
  '""' => sub { $_[0] },
  bool => sub { ! $_[0]->done_p() },
  '++' => \&inc,
  '='  => sub { $_[0] },
;

sub new {
  my ( $class, $arg ) = @_;
  my $self = {};
  bless $self, $class;
  $self->set ( $arg );
  return $self;
}

sub set     { $_[0]->{_i} = $_[1] }
sub get     { return $_[0]->{_i} }
sub inc     { ++$_[0]->{_i} }
sub done_p  { $_[0]->{_i} > 5 }
sub DESTROY { print "Destroying $_[0]\n" }

package main;
use Devel::Peek;

my $a = Toy_Iterator->new ( 2 );

while ( $a++ ) {
  print "$a -> " . $a->get() . "\n";
}

# print "\n"; Dump $a; print "\n";

print "undef'ing \$a...\n";
undef $a;
print "done undef'ing\n";

##</code><code>##

Toy_Iterator=HASH(0x80fbc2c) -> 3
Toy_Iterator=HASH(0x80fbc2c) -> 4
Toy_Iterator=HASH(0x80fbc2c) -> 5
undef'ing $a...
done undef'ing
Destroying Toy_Iterator=HASH(0x80fbc2c)

##</code><code>##

Toy_Iterator=HASH(0x80fbc2c) -> 3
Toy_Iterator=HASH(0x80fbc2c) -> 4
Toy_Iterator=HASH(0x80fbc2c) -> 5
undef'ing $a...
Destroying Toy_Iterator=HASH(0x80fbc2c)
done undef'ing