# File lib/declarative_authorization/development_support/development_support.rb, line 176
        def descendants (priv_symbol = nil)
          priv_symbol ||= @privilege
          # context-specific?
          (@engine.privilege_hierarchy[priv_symbol] || []).
              collect {|lower_priv, context| descendants(lower_priv) }.flatten +
            (priv_symbol == @privilege ? [] : [Privilege.for_sym(priv_symbol, @engine)])
        end