package MyPackage::Module::ThisFeature;
use base MyPackage::Module;

##</code><code>##

use Test::More 'no_plan';
my $obj = MyPackage::Module::ThisFeature->new();
isa_ok($obj,'MyPackage::Module');
isa_ok($obj,'MyPackage::Module::ThisFeature');
isa_ok($obj,'MyPackage::Module::ThatFeature');

##</code><code>##

perl 01-test.t
ok 1 - The object isa MyPackage::Module
ok 2 - The object isa MyPackage::Module::ThisFeature
not ok 3 - The object isa MyPackage::Module::ThatFeature

##</code><code>##

#!/usr/bin/perl -wT
use strict;
use warnings;

use MyPackage::Module::ThisFeature;
use MyPackage::Module::ThatFeature;

my $obj = MyPackage::Module::ThisFeature->new();
my $result = $obj->this_method();
   .   .   .   


##</code><code>##

package MyPackage::Module;

sub new {
    .  .  .  

  bless $self, $class;
}

sub this_method {

}

sub that_method {

}

1;

package MyPackage::Module::ThisFeature;

use base MyPackage::Module;

sub this_method {

}

sub some_other_method {

}

1;

package MyPackage::Module::ThatFeature;

use base MyPackage::Module;

sub that_method {

}

sub still_another_method {

}

1;