python：object（）没有参数错误

Question

I'm trying to create an enum class in python2.7. My code looks like this:

from enum import Enum

class Alarms(Enum):
    MOTION = "Motion", 0, False
    SOUND = "Sound", 1, False
    FIRE = "Fire", 2, False


    def __new__(cls, *args, **kwds):
        obj = object.__new__(cls)
        obj.value_ = args[0]
        return obj

    def __init__(self, name, modbusAddress, isActive):
        self.name = name
        self.modbusAddress = modbusAddress
        self.isActive = isActive

This is the error message I get:

  File "/usr/lib/python2.7/dist-packages/enum/__init__.py", line 232, in __new__
    enum_member._value_ = member_type(*args)
TypeError: Error when calling the metaclass bases
    object() takes no parameters

Answer 1

Try the below snippet

from enum import Enum

class Alarms(Enum):
    MOTION = ("Motion", 0, False)
    SOUND = ("Sound", 1, False)
    FIRE = ("Fire", 2, False)

    def __new__(cls, *args, **kwds):
        obj = object.__new__(cls)
        obj.value_ = args[0]
        return obj

    def __init__(self, name, modbusAddress, isActive):
        self._name = name
        self._modbusAddress = modbusAddress
        self._isActive = isActive

Answer 2

You have a typo in your __new__ :

obj.value_ = args[0]

should be

obj._value_ = args[0]

(notice the leading underscore)

If you do want a value_ attribute, then you need to set both.