my $caller_pkg = caller();
    
    # meta model helpers
    *{$caller_pkg . '::class'} = \&class;
    *{$caller_pkg . '::role'}  = \&role;
    
    # instance attribute access helpers
    *{$caller_pkg . '::_'} = \&_; 
    # class attribute access helpers
    *{$caller_pkg . '::__'} = \&__;