#!/usr/bin/perl
use strict;

package person;
sub new
{
        my $class = shift(@_);
        #my $self  = { 'name' => 'Alice' };
        my $self = { 'name' => shift };
        bless($self, $class);
        return($self);
}

sub tellName  {
        my($self)=$_[0];
        print "$self->{'name'}.\n";
}

sub introduce {
        my($self)=$_[0];
        print "Hello, I'm ";
        #$self->tellName();
        person::tellName($self);
}
1;

package child;
our @ISA = qw(person);    # inherits from person
sub new {
        my $class = shift(@_);
        #my $self = $class->SUPER::new();
        my $self = $class->SUPER::new(shift);
        #$self ->{'nickName'} = 'Billy The Kid';
        $self ->{'nickName'} = shift;
        $self->{mom} = shift;
        $self->{dad} = shift;
        bless $self, $class;
        return $self;
}

sub tellName  {
        my($self)=$_[0];
        print "$self->{'nickName'}.\n";
}

sub introduce {
        #my($self)=$_[0]; print "Hi, I'm ";
        my($self)=$_[0]; 
        $self->SUPER::introduce();
        print 'but they also call me ';
        $self->tellName;
        print "Here's my mom: ";
        #$self->SUPER::introduce();
        $self->{mom}->introduce;
        print "Here's my dad: ";
        $self->{dad}->introduce;
}
1;



package main;

my $mom = new person('Alice');
my $dad = person->new('Charlie');
$mom->introduce();      # that time it works.
$dad->introduce;

print "\n";

my $son = new child('Billy', 'Billy the Kid', $mom, $dad);
$son->introduce();

##</code><code>##

Hello, I'm Alice.
Hello, I'm Charlie.

Hello, I'm Billy.
but they also call me Billy the Kid.
Here's my mom: Hello, I'm Alice.
Here's my dad: Hello, I'm Charlie.