hi all,

my question is quite simple: is it possible to individually override a method an object has inherited from its mother class? 
package MyMother;
use strict;
use vars qw/@ISA/;
use Exporter;
@ISA = qw/Exporter/;

sub new {
   my ($class, @args) = @_;
   my $self = { MODIFIED => 0,
                TYPE => $args[0],
              };
   bless $self, $class
}

sub modified { $_[0]->{MODIFIED} }

[download]
so far for the mother class, here's the child: 
package MyChild;
use strict;
use vars qw/@ISA/;
use MyMother;
@ISA = qw/MyMother/;

sub new {
   my ($class, @args) = @_;
   my $self = $class->SUPER::new(@args);
   bless $self, $class;
   if ($self->{TYPE} == 1) {
     $self->modified = sub { 0 };
   }
   $self;
}

[download]
the script for testing: 
#!/usr/bin/perl -wd
use MyChild;
my $ch = MyChild->new(2);
$ch->{MODIFIED} = 1;
print $ch->modified."\n";
$ch = MyChild->new(1);
$ch->{MODIFIED} = 1;
print $ch->modified."\n";

[download]
as you can see, my intention is to make some certain instances always return the false value in a call to $obj->modified. the thing is that $self->modified = sub { 0 }; produces the error: "Can't modify non-lvalue subroutine call at MyChild.pm line 12", whereas $self::modified = sub { 0 } has no effect.

maybe that question has been put here already sometime, i couldn't find it by a search query. however, if you happen to find an appropriate node, please let me know. (even if it's the link to a manpage. ;-))

many thx in advance
TOD
--------------------------------
masses are the opiate for religion.

In reply to "individually" override a super class's object methods by TOD

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