如果mutable,那么call function前后指向的object的值可能会发生变化,如果是immutable则肯定不会。如果在调用的function中,出现了“=”,那么不论mutable或immutable,function argument的那个variable name都会从那一刻起指向另一个object,其scope仅限于callee function。 2020.2.1
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...
python学习之---mutable python的数据类型分为mutable(可变) 和 immutable (不可变) mutable : list ,dict inmutable : int , string , float ,tuple... mutable和immutable 字面意思理解就是说数据可变和数据不可变 由于python的变量(variable)不需要声明,而在赋值的时候,变量可以重新赋值为任意值,这就涉及到Py...
python里面的类型其实也分为immutable和mutable二种,对于mutable,如果b指向a,当b改变时,a也会改变;对于immutable,如果b改变,不会影响a。 参考:http://www.ibaiyang.org/2012/05/04/howtopython/
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 12332、
python immutable and mutable python mutable as default parameter(NONONO) def f(l=[]): l.append(l) print(l) f() f() 那么在python那些是immutable呢? numbers, strings, tuples, frozensets 其实,还有一种特殊情况,就是自定义的类型呢? 一般情况下,程序员自定义的python类型都是mutable的,但是如果你...
Your Own Immutable Objects Python is very flexible and it gives you a lot of control over how to customize its behavior. As you can see from the list at the beginning of this article, custom created classes belong to the mutable types. But what happens if you want to define your own i...
>>> s.append(4)>>> s [1, 2, 3, 4]>>> id(s)46985544L >>> id([1,2,3])46987080L >>> id([1,2,3,4])47011016L add,append类似的方法创建了新的对象,关键在于python中的变量是对象的引用(s是对[1,2,3]的引用),对象的改变创建了新的对象([1,2,3]+[4]),变量指向...
TL;DR: What are mutable and immutable objects in Python? Mutable objects in Python are those that can be changed after they are created, like lists or dictionaries. Immutable objects, on the other hand, cannot be changed after they are created, such as strings, integers, or tuples. To be...