python - 在 Python 中传递值

Question

这个问题在这里已经有了答案:

How do I pass a variable by reference? (39 个回答)

关闭 9年前。

当你将一个集合(如列表、数组)传递给 python 中的另一个函数时，它是复制它，还是只是一个指针？

Answer 1

Python passes references-to-objects by value .

Python passes references-to-objects byvalue (like Java), and everything inPython is an object. This soundssimple, but then you will notice thatsome data types seem to exhibitpass-by-value characteristics, whileothers seem to act likepass-by-reference... what's the deal?

It is important to understand mutableand immutable objects. Some objects,like strings, tuples, and numbers, areimmutable. Altering them inside afunction/method will create a newinstance and the original instanceoutside the function/method is notchanged. Other objects, like listsand dictionaries are mutable, whichmeans you can change the objectin-place. Therefore, altering anobject inside a function/method willalso change the original objectoutside.