# File lib/declarative_authorization/development_support/development_support.rb, line 95
        def ancestors (role_symbol = nil)
          role_symbol ||= @role
          (@engine.role_hierarchy[role_symbol] || []).
              collect {|lower_role| ancestors(lower_role) }.flatten +
            (role_symbol == @role ? [] : [Role.for_sym(role_symbol, @engine)])
        end