singleton_pattern.py
· 242 B · Python
Исходник
class Singleton:
_instance = None
def __new__(cls):
if cls._instance is None:
cls._instance = super().__new__(cls)
return cls._instance
a = Singleton()
b = Singleton()
print(a is b) # True，同一個
| 1 | class Singleton: |
| 2 | _instance = None |
| 3 | |
| 4 | def __new__(cls): |
| 5 | if cls._instance is None: |
| 6 | cls._instance = super().__new__(cls) |
| 7 | return cls._instance |
| 8 | |
| 9 | |
| 10 | a = Singleton() |
| 11 | b = Singleton() |
| 12 | |
| 13 | print(a is b) # True，同一個 |
| 14 |