package HashRefAsObject;

sub new1 { # using a hash ref as an object
 my $class = shift;
 my $self = { }; # hash ref
 bless( $self, $class );
 $self->{varA} = 123; # set "instvar"
 $self->{varB} = 456;  # another
 return $self;
}

package ArrayRefAsObject;

sub new2 {  # using an array ref as an object
 my $class = shift;
 my $self = []; # array ref
 bless( $self, $class );
 $self->[0] = 123; # set "instvar"
 $self->[1] = 456; # another
 return $self;
}

package Foo; # Using pseudo-hashes
# from fields manpage:
use fields qw(foo bar _Foo_private);
sub new {
 my Foo $self = shift;
 unless (ref $self) {
  $self = fields::new($self);
  $self->{_Foo_private} = "this is Foo's secret";
 }
 $self->{foo} = 10;
 $self->{bar} = 20;
 return $self;
}