This modified code demonstrates package inlining and inheritance. For small scripts, I like to inline a package once in a while, escpecially when subclassing a standard module. if I put the main package before the other packages, it doesn't work.

#!/usr/bin/perl
use warnings;
no warnings qw/uninitialized/;
use strict;
use Data::Dumper;


#######################

    package Class1;
    
    sub new {
        my $classname  = shift;
        my $self       = {@_};
        $self->{NAME}   = undef unless $self->{NAME};
        $self->{AGE}    = undef unless $self->{AGE};
        bless($self,$classname);
        return $self;
    }

    sub PrintHello
    {
        my $this = shift;
        print "$this->{TITLE}\tHello $this->{NAME}\t$this->{AGE}\n";;
    }


#######################

    package Class2;
    
    our @ISA = qw(Class1);
   
    sub new {
        my $class  = shift;
        my $self       = $class->SUPER::new(@_);
        $self->{TITLE}  = 'This is Class2';
        return $self;
    }
########################

package main;
my $max = Class1->new(NAME=>'Someone Else',AGE=>42);
my $max2 = Class2->new(NAME => 'MaxKlokan',AGE=>21) ;
$max2->PrintHello();
print Dumper $max;
print Dumper $max2;
exit;
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