Python基础-使用__slots__

slots

不带 slots 的demo

#!/usr/bin/env python3
# -*- coding: utf-8 -*-
# __slots__

class Student1(object):
pass

def runTest1():
s = Student1()
s.name = "蜡笔小新"
s.age = 6
s.score = 100
print("%s:%d:%d"%(s.name, s.age,s.score))

runTest1()

D:\PythonProject\sustudy>python main.py
蜡笔小新:6:100

带 slots 的demo

class Student2(object):
# 用tuple定义允许绑定的属性名称
__slots__ = ('name', 'age')

def runTest2():
s = Student2()
s.name = "蜡笔小新"
s.age = 6
s.score = 100
print("%s:%d:%d"%(s.name, s.age,s.score))

runTest2()

Traceback (most recent call last):
File "main.py", line 30, in <module>
runTest2()
File "main.py", line 27, in runTest2
print("%s:%d:%d"%(s.name, s.age,s.score))
AttributeError: 'Student2' object has no attribute 'score'