在python中實現final類

• 2019 年 11 月 21 日
• 筆記

當然要利用下metaclass做手腳啦

class Final(type):      def __new__(cls, name, bases, classdict):          for b in bases:              if isinstance(b, Final):                  raise TypeError("type '{0}' is Final type".format(b.__name__))          return type.__new__(cls, name, bases, dict(classdict))      class Hi(object):      def hi(self):          print("hi")      class SubHi(Hi, metaclass=Final):      pass    # 這個沒問題  s = SubHi()  s.hi()    # TypeError: type 'SubHi' is Final type  class SubHi2(SubHi):      pass