这是因为a指向的1是一个immutable对象,也就是不可变对象,如果试图去改变一个immutable对象,在python中执行的操作就是在内存中重新创建一个对象,然后把变量指向这个新的对象,也就是说不可变对象的值是不可变的,这个类似于const类型的变量,如果试图通过某个引用去修改不可变对象,python就会在内存中新建一个对象...
Mutable objects can be changed, while immutable objects can't. In Python, strings are immutable, so strings can't be edited "in place". You have to make a copy.
这期视频讲一下mutable和immutable,也就是可变对象和不可变对象。很多人可能压根没意识到,python对于mutable和immutable的操作是完全一致的,也就是python根本无法区分一个对象是mutable还是immutable。那这个概念背后到底有着什么值得思考的内容呢?, 视频播放量 9178、
In this lesson, you will learn what mutable and immutable objects are, and the difference between them. This understanding will help you determine when objects can be modified in place, and when new objects must be created. List is mutable, which means everytime it returns the same id whethe...
常見的immutable objects: Numeric types: int, float, complex string tuple frozen set 常見的mutable objects: list dict set byte array Case One >>>a=[1, 2, 3]>>>id(a)4317018016>>>a[1]=10>>>id(a)4317018016>>>a[1, 10, 3]
这里可能有点绕,不过这里也就是所说的mutable和immutable的问题了,在Python中,immutable的类型有整数、浮点数、字符串以及元组等等,而mutable的类型有list,dict以及自定义的类型。 那么回到上面一开始的问题中,知道了list是mutable的,所以在创建的时候,并不是赋值到了新的位置,只是创建了三个指针(a[0], a[1], ...
In this lesson, you will learn what mutable and immutable objects are, and the difference between them. This understanding will help you determine when objects can be modified in place, and when new objects must be created. List is mutable, which means everytime it returns the same id whethe...
python的基本类型中,分为mutable和immutable。mutable就是创建后可以修改,immutable就是创建后不能修改的。(一般的user defined class都是mutable,当然想要immutable的可以专门搜索一下“python custom immutable class”) 图片来源:https://medium.com/@meghamohan/mutable-and-immutable-side-of-python-c2145cf72747 ...
You see that you updated the value of var1 and the value of var2 also changed. This happens only with mutable types. With immutable objects, since a new object is created in order to update a value, then each name will be pointing to a different object. For example, with strings:...
mutable-Java中mutable对象和immutable对象的区别,Python的数据类型分为可变(mutable)与不可变(immutable)。不可变类型包含字符串(str),整数(int),元组(tuple);可变类型包含列表(list),字典(dict)。是否为可变类型在于内存单元的值是否可以被改变。如果是内存单元的值