# taken from: http://perldoc.perl.org/perlobj.html
use strict;
use warnings;
use 5.014;

package A;
  sub new {
      return bless {}, shift;
  }
  sub speak {
      my $self = shift;
      $self->SUPER::speak();
      say 'A';
  }
package B;
  use parent 'A';
  sub speak {
      my $self = shift;
      $self->SUPER::speak();
      say 'B';
  }
package C;
  use parent 'B';
  sub speak {
      my $self = shift;
      $self->SUPER::speak();
      say 'C';
  }
  my $c = C->new();
  $c->speak();