# File lib/brakeman/tracker/model.rb, line 42
    def set_attr_accessible exp = nil
      if exp
        args = []

        exp.each_arg do |e|
          if node_type? e, :lit
            args << e.value
          elsif hash? e
            @role_accessible.concat args
          end
        end

        @attr_accessible ||= []
        @attr_accessible.concat args
      else
        @attr_accessible ||= []
      end
    end