|
纠结的元组到底可变不可变
>>> x = (1,2,3)
# 元组中的元素不可修改
>>> x[0] = 4
Traceback (most recent call last):
??File "",line 1,in
????x[0] = 4
TypeError: 'tuple' object does not support item assignment
>>> x = ([1,2],3)
# 不能修改元组中的元素值
>>> x[0] = [3]
Traceback (most recent call last):
??File "",in
????x[0] = [3]
TypeError: 'tuple' object does not support item assignment
>>> x
([1,3)
>>> x[0] = x[0] + [3]
Traceback (most recent call last):
??File "",in
????x[0] = x[0] + [3]
TypeError: 'tuple' object does not support item assignment
>>> x
([1,3)
# 这里有个坑，虽然显示操作失败了，但实际上成功了
>>> x[0] += [3]
Traceback (most recent call last):
??File "",in
????x[0] += [3]
TypeError: 'tuple' object does not support item assignment
>>> x
([1,3],3)
>>> x[0].append(4)
>>> x
([1,3,4],3)
# y和x[0]指向同一个列表，通过其中一个可以影响另一个
>>> y = x[0]
>>> y += [5]
>>> x
([1,4,5],3)
# 执行完下面的语句，y和x[0]不再是同一个对象
>>> y = y + [6]
>>> x
([1,3)
>>> y
[1,5,6]
---------------------?
作者：dongfuguo?
来源：CSDN?
原文：https://blog.csdn.net/dongfuguo/article/details/53968555?
版权声明：本文为博主原创文章，转载请附上博文链接！ （编辑：李大同）
【声明】本站内容均来自网络，其相关言论仅代表作者个人观点，不代表本站立场。若无意侵犯到您的权利，请及时与联系站长删除相关内容!
|
