Python Basics (deep, shallow copy)

Deep, shallow copy

Base: Object, reference, variable and variable

For immutable objects, such as strings, tuples, and digital shades, there is no point.

1. Shallow copy

A shallow copy only copies the first layer of the object (the actual copy is a frame, the copy of the past frame will not change, but the original frame has a variable object, modify the inside of the frame will be changed )

>>> import Copy>>> a = [1,2,[1,2],3]>>> B = copy.copy (a) >>> b              #b拷贝的是a的第一层框子 [1, 2 , [1, 2], 3]>>> a.append (4)        #a对象发生了更改, B object did not change >>> b                  

Python Basics (deep, shallow copy)