This is my first Moose experiment. Suggestions for improvement are welcome.

In this code, class ThreeD has a class variable $active_model. $active_model is a ThreeD::Model object which has an $active_entities variable.

On line 19, ThreeD::Model->new() is called, but the constructor is never actually run. Line 20 attempts to get the active_entities from the new model, but fails saying that there is no active_entities method in ThreeD::Model.

Expected output:

DEBUG
DEBUG3
DEBUG2
DEBUG2a
DEBUG1a
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Actual output:

DEBUG
Can't locate object method "active_entities" via package "ThreeD::Mode
+l" at /home/john/workspace/TestOOP/MY/ThreeD.pm line 13.
[download]

The code:

#!/usr/bin/perl
#

package ThreeD;
use Moose;
use MooseX::ClassAttribute;
use namespace::autoclean;

class_has 'active_model' => (isa => 'Model',
                                is => 'ro',
                                default => sub {print "DEBUG\n"; 
                                                my $model = ThreeD::Mo
+del->new();
                                                my $entities = $model-
+>active_entities;
                                                print "DEBUG 1a\n";
                                                return $model});

__PACKAGE__->meta->make_immutable;
no Moose;
no MooseX::ClassAttribute;
1;

{
   package ThreeD::Model;
   use Moose;
   use namespace::autoclean;

   has 'active_entities' => (isa => 'Entities',
                             is => 'ro',
                             lazy => 0,
                             default => sub {print "DEBUG 2\n"; 
                                              my $entities = ThreeD::E
+ntities->new();
                                             print "DEBUG 2b\n";
                                             return $entities});

   around BUILDARGS => sub {
      my ($orig, $class, %args) = @_;
      print "DEBUG 3\n";
      return $class->$orig(%args);
   };
                      
   __PACKAGE__->meta->make_immutable;

   1;
}

{
   package ThreeD::Entity;
   use Moose;
   use namespace::autoclean;
   use MooseX::FollowPBP;

   my $my_index = 0;
   
   has 'entityID' => (isa => 'Int',
                      is => 'ro',
                      required => 1);
                      
   around BUILDARGS => sub {
      my ($orig, $class, %args) = @_;
      $args{entityID} = $my_index;
      $my_index++;
      return $class->$orig(%args);
   };
   
   __PACKAGE__->meta->make_immutable;

   1;
}

{
   package ThreeD::Entities;
   use Moose;
   use namespace::autoclean;
   #use MooseX::FollowPBP;
   use OpenGL;

   has 'entity' => (isa => 'ArrayRef[ThreeD::Entity]',
                      is => 'rw',
                      default => sub {[]});
 
   __PACKAGE__->meta->make_immutable;

   1;
}



package main;

use strict;
use warnings;

my $model = ThreeD->active_model;
my $entities = $model->active_entities;
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