cumulative role attrs? role meta attrs?

Hi.  I tried to follow the example in
Moose::Cookbook::Meta::Recipe5 but I got this error: 'Can't
locate object method "table" via package
"Moose::Meta::Class::__ANON__::SERIAL::1'.  I filed a bug.

What I am trying to do is create a container object for
another class of objects, apply selected roles to the
container on construction, which tell it what other roles to
apply to the contained objects.

I.e.

 my $hostset = My::HostSet
     ->with_traits(qw( Cluster Hardware ))
     ->new( hostnames => [qw( foo bar baz )]);

 package My::HostSet;
 with 'MooseX::Traits';
 has '+_trait_namespace' => ( default => 'My::Role::HostSet' );
 use My::Host;
 use Moose::Util qw( apply_all_roles );

 has hostnames (
     # ...
 );
 has hosts (
     # ...
     lazy_build => 1,
 );
 sub _build_hosts {
     my @hosts = map My::Host->new( hostname => $_ ), @{$hostnames};

     my @contained_object_roles = foo();  # ...
     # here I want to find out from My::Role::HostSet::Cluster
     # and My::Role::HostSet::Hardware what other roles it
     # should apply to the contained objects.

     apply_all_roles( $_, @contained_object_roles ) for @hosts;
     return \@hosts;
 }

I don't see a good way to do this.  Having same name attribute in
each HostSet role class conflicts, obviously.  I thought maybe
adding meta attributes to the HostSet role classes would be
the way to go, but the example doesn't work.

I don't know what I'm doing... thanks.  :-)

Mark