package bar;

# base class. Has a description method and an id method

sub new {
 my $proto = shift;
 my $class = ref($proto) || $proto;
 my $self = {};
 $self->{DESCRIPTION} = "Bar!!!";
 bless($self,$class);
 return $self;
}

sub description 
{ my $self = shift;
  return $self->{DESCRIPTION};
}
# return a description

sub id { return __PACKAGE__; }

# return the package name

package foo;

# inheriting from bar package, not overriding the id method.

@ISA = qw(bar);

use bar;

sub new {
 my $proto = shift;
 my $class = ref($proto) || $proto;
 my $self = $class->SUPER::new;
 $self->{DESCRIPTION} = "Foo!!";
 # yes I'm lazy :)
 bless($self,$class);
 return $self;
}

package main;

use foo;

$foo = new foo;
print "Description is ",$foo->description,"\n";
print "Package is ",$foo->id,"\n";