有什么办法可以避免在初始化类时调用__init__
,比如从类方法中?Python:在不调用初始化程序的情况下创建类实例
我想在Python中创建一个用于高效比较的案例和标点符号不敏感的字符串类,但在创建新实例时无法调用__init__
。
>>> class String:
def __init__(self, string):
self.__string = tuple(string.split())
self.__simple = tuple(self.__simple())
def __simple(self):
letter = lambda s: ''.join(filter(lambda s: 'a' <= s <= 'z', s))
return filter(bool, map(letter, map(str.lower, self.__string)))
def __eq__(self, other):
assert isinstance(other, String)
return self.__simple == other.__simple
def __getitem__(self, key):
assert isinstance(key, slice)
string = String()
string.__string = self.__string[key]
string.__simple = self.__simple[key]
return string
def __iter__(self):
return iter(self.__string)
>>> String('Hello, world!')[1:]
Traceback (most recent call last):
File "<pyshell#2>", line 1, in <module>
String('Hello, world!')[1:]
File "<pyshell#1>", line 17, in __getitem__
string = String()
TypeError: __init__() takes exactly 2 positional arguments (1 given)
>>>
我应该代替string = String(); string.__string = self.__string[key]; string.__simple = self.__simple[key]
与初始化与片新对象?
编辑:
至于灵感来自下面写答案,初始化已被编辑以快速检查没有参数。
def __init__(self, string=None):
if string is None:
self.__string = self.__simple =()
else:
self.__string = tuple(string.split())
self.__simple = tuple(self.__simple())
可能的重复[有没有一种方法来实例化一个类,而不会调用\ _ \ _ init \ _ \ _?](http:// stackoverflow。com/questions/6383914/is-there-a-way-to-instantiate-a-class-without-calling-init) – kay 2013-10-31 23:22:25