Multiple inheritance: Baz uses Bar as a base, who uses Foo as a base.

Baz.pm

package Baz;
use base "Bar";
1;

Foo.pm

package Foo;

sub new {
  my $class = shift;
  return bless {}, $class;
}

sub exclaim { 
    $self = @_;
    print "I can have such a thing?!\n";
}
1;

perl inheritance. Bar.pm

package Bar;
use base "Foo";
sub from_bar { 
    $self = @_;
    "I come from Bar" 
}

sub exclaim { 
    $self = @_;
    print "I come from Bar\n"; 
    $self->SUPER::exclaim(); 
}
1;

test.pm

use Baz;

my $ob = Baz->new();
$ob->exclaim();