#!/usr/bin/perl

package MySubClass;
use MyClass;
use strict;
our @ISA = qw(MyClass);    # inherits from MyClass

# Override constructor
sub new {
    my ($class) = @_;

    # Call the constructor of the parent class, Person.
    my $self = $class->SUPER::new( $_[1] );
    # Add few more attributes
    $self->{_arg2}   = $_[2];
    bless $self, $class;
    return $self;
}

# Override helper function
sub getarg1 {
    my( $self ) = @_;
    # This is child class function.
    return $self->{_arg1};
}

# Add more methods
sub setarg2{
    my ( $self, $arg2 ) = @_;
    $self->{_arg2} = $arg2 if defined($arg2);
    return $self->{_arg2};
}

sub getarg2 {
    my( $self ) = @_;
    return $self->{_arg2};
}

1;

#my $obj1 = new MyClass "obj1";
#my $obj2 = MySubClass->new("obj2_1","obj2_2");

#print "a1:" . $obj1->getarg1() . "\n";
#$obj1->setarg1("arg1");
#print "a2:" . $obj1->getarg1() . "\n";

#print "b1:" . $obj2->getarg1() . "\n";
#$obj2->setarg1("arg1");
#print "b2:" . $obj2->getarg1() . "\n";

#print "b3:" . $obj2->getarg2() . "\n";
#$obj2->setarg2("arg2");
#print "b4:" . $obj2->getarg2() . "\n";