# File lib_wpm/wpm.rb, line 1462
    def set_property(name, attr_map, value)
      case (name)
      when 'condition'
        @condition = get_property(attr_map, value, 'bool', 'accessor', 'eval')
      when 'negate'
        @negate = get_property(attr_map, value, 'bool', 'accessor', 'eval')
      else
        raise PropertyError, "unknown property: #{name.inspect}: at #{widget_id.inspect}"
      end

      nil
    end