Config::Model::Itself::BackendDetector3pm

 # this class should be referenced in a configuration model and
 # created only by Config::Model::Node
 my $model = Config::Model->new() ;
 $model ->create_config_class
  (
   name => "Test",
   'element'
   => [ 
       'backend' => { type => 'leaf',
                      class => 'Config::Model::Itself::BackendDetector' ,
                      value_type => 'enum',
                      # specify backends built in Config::Model
                      choice => [qw/cds_file perl_file ini_file custom/],
                      help => {
                               cds_file => "file ...",
                               ini_file => "Ini file ...",
                               perl_file => "file  perl",
                               custom => "Custom format",
                              }
                    }
      ],
  );
  my $root = $model->instance(root_class_name => 'Test') -> config_root ;
  my $backend = $root->fetch_element('backend') ;
  my @choices = $backend->get_choice ;