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Most people do not understand the knowledge points of this article "Python decorator how to use code to achieve", so the editor summarizes the following contents, detailed contents, clear steps, and has a certain reference value. I hope you can get something after reading this article. Let's take a look at this "Python decorator how to use code to achieve" article.

Before I talk about the Python decorator, I would like to give an example. Although it is a little dirty, it is very relevant to the topic of the decorator.

Before talking about decorators, we should understand that the functions in Python are different from those in Java and C++. Functions in Python can be passed to another function as arguments like ordinary variables, for example:

Let's start with a simple example, although the actual code may be much more complex than this:

Now there is a new requirement that you want to record the execution log of the function, so add the log code to the code:

Simple decorator

@ grammatical sugar

* args, * * kwargs

One might ask, what if my business logic function foo requires parameters? For example:

We can specify parameters when defining the wrapper function:

For example:

At this point, you can assign the wrapper function to the keyword function:

Decorator with parameters

@ use_logging (level= "warn") is equivalent to @ decorator

Class decorator

Functools.wraps

Example:

Decorator sequence

A function can also define multiple decorators at the same time, such as:

The above is about the content of this article on "how to implement Python decorator in code". I believe we all have a certain understanding. I hope the content shared by the editor will be helpful to you. If you want to know more about the relevant knowledge, please pay attention to the industry information channel.

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