import abc
class SetterGetter(object):
__metaclass__ = abc.ABCMeta
@abc.abstractmethod
def set_val(self, inp):
return
@abc.abstractmethod
def get_val(self):
return
class TryAbsMethod(SetterGetter):
def get_val(self):
return self.inp
def set_valz(self, inp):
self.inp = inp
a = TryAbsMethod()
print(a)
根据教程,我期望从上面的代码中得到好处,但是我却从python得到了输出,这很奇怪,有人可以解释一下为什么吗?
输出得到
/usr/bin/python3.4 /home/murtuza/MyCodes/abstract.py
<__main__.TryAbsMethod object at 0x7f93ba8ab048>
Process finished with exit code 0
预期的异常
TypeError: Can't instantiate abstract class TryAbsMethod with abstract method set_val
最佳答案
您正在使用Python3.x。在Python 3.x中,元类声明语法已更改。
class SetterGetter(object, metaclass=abc.ABCMeta): # <---
@abc.abstractmethod
def set_val(self, inp):
return
@abc.abstractmethod
def get_val(self):
return
请参见Customizing class creation - Data model - Python 3.x documentation,PEP3115 - Metaclasses in Python 3
关于python - python中的抽象方法,我们在Stack Overflow上找到一个类似的问题:https://stackoverflow.com/questions/32431272/