Use of uninitialized value in addition (+) at Parent.pm line 17.
Use of uninitialized value in addition (+) at Parent.pm line 17.
##</code><code>##


 package Parent;
 use strict;
 use warnings;
 use Carp;
 use Data::Dumper;
 
 use Class::MethodMaker
 get_set => [ 
              { -read_cb => sub {  ## THIS ONE IS NOT WORKING .........                                
			my ($self,$val1,$val2) = shift;
                        $self->{val1} = $val1;
                        $self->{val2} = $val2;

##</code><code>##

my $out =  $self->{val1} + $self->{val2};
              return $out;
                         }
             },'add',
             { -read_cb => sub {
                                  $_[1] - 1;
                               }
             },'subtract'
            ],
 new => 'new';
1;



# Child Class .............

 package Child;

 use Data::Dumper;
 use Parent;

 my (%val1,%val2);
 sub new {

  bless [ ] => shift;

 }

 sub subtract {
    $self = shift;
    $val1{$self}=shift;
    $val2{$self}=shift;
    return $val1{$self}-$val2{$self};
 }

 $myobj = Child->new();
 $subobj=$myobj->subtract(34,31); # this method s working 
 print Dumper $subobj;


 $pObj = Parent->new(); # This is not working 
 $pObj->add(100,3);
 print Dumper $pObj;

 $pObj=Parent->subtract(100); # subtracts 1 from 100 .
 print Dumper $pObj;