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


sub MotionSensorA::new { bless { type => $_[1] }, $_[0] }
sub MotionSensorB::new { bless { type => $_[1] }, $_[0] }

{   package Device;
    use Moose;

    has laboratory  => (is      => 'ro',
                        isa     => 'MotionSensorB',
                        default => sub {
                            'MotionSensorB'->new('senMotion_H2_S1');
                        });
    has fruitcellar => (is      => 'ro',
                        isa     => 'MotionSensorA',
                        default => sub {
                            'MotionSensorA'->new('senMotion_H1_S1');
                        });

    sub event {
        my ($self) = @_;

        foreach my $device ($self->meta->get_attribute_list) {
            print "$device: ", $self->$device->{type}, "\n";
        }
    }
    __PACKAGE__->meta->make_immutable;
}

my $d = 'Device'->new;
$d->event;