Python Tutorial: Decorators - Dynamically Alter The Functionality Of Your Functions
Why Stack Overflow recommends it
Stack Overflow users link it when answering questions about the @ syntax and decorators, as a clear walkthrough to learn them from.
Recommended by 3 people across 4 different months, 2018 to 2022.
What it is
A 30-minute Python tutorial by Corey Schafer explaining decorators: functions that wrap other functions to add behavior such as logging without changing the original code. He builds up from simple wrappers to handling arguments with *args and **kwargs, and points to his earlier videos on first-class functions and closures as prerequisites.
What people said
Recommends user4851126 · 2018-08 · Stack Overflow · on “@ operator at the beginning of the line in python”
I think what you are looking for is called PythonDecorators Here is the Wiki For Python Decorators [LINK] A Python decorator is a specific change to the Python syntax that allows us to more conveniently alter functions and methods (and possibly classes in a future version). This supports more readable applications of the DecoratorPattern but also other uses as well. The best way to understand them is from Corey Schafer's Video on Python Decorators [this video]
Recommends Mandera · 2020-08 · Stack Overflow · on “Dash callback 'unexpected EOF while parsing' bug”
You are using @ for some reason without a following function definition. @ is the syntax for a decorator, if you don't have a following function definition then you will get SyntaxError: unexpected EOF while parsing . A simple decorator looks like this: @decoratorFunctionThatReturnsAnotherFunction def myDecoratedFunction(): pass Recommending Corey Schafer's video about decorators on YouTube: [this video]
Recommends Matiiss · 2020-10 · Stack Overflow · on “Is there a way to find out what function was called within a list comprehension in another function?”
because you do not have to edit the function directly to add functionality. they are called decorators and I do not really know about them much but here is a video that may be helpful this link [this video] However it will still require you to do some changes to test.py
Recommends Mandera · 2020-11 · Stack Overflow · on “Is there a clean way to check a variable inside a loop on the first iteration only or before its execution?”
Glad I could help! I recommend this answer [LINK] or this video [this video] to learn wrappers and decorators. `_visual_decorator` takes any _callable_ as an argument and returns another _callable_ with the same _signature_. The returned _callable_, once called, will in our case call the `print` function and then return the result of the first given _callable_.
Cites Josh · 2019-06 · Stack Overflow · on “Python inner functions/decorators: When should I use parentheses when returning an inner function?”
I am learning about Python decorators and inner functions and have some questions about the lesson I'm learning via a YouTube video from codeacademy.com [LINK] . When using inner functions sometimes I have to return the function with parenthesis, and sometimes without. If I call an inner function without using decorators, I have to use parentheses when returning the inner function, otherwise it seems the inner function is returned as an object(?). In the YouTube video from codeacademy.com as well as this one [this video] , they call the inner function without parentheses and the expected result is output. If I call an inner function using decorators, I have to not use parentheses when returning t
Cites Thingamabobs · 2021-12 · Stack Overflow · on “How can I make a sound when a button is pressed?”
I think you want to alter your functions with a common functionality. For this decorators [this video] are really good. A decorator allows you to add functionality to existing functions. An exampel can be found below: import tkinter as tk import winsound as snd def sound_decorator(function): def wrapped_function(*args,**kwargs): print('I am here') snd.PlaySound('Sound.wav', snd.SND_FILENAME) return function(*args,**kwargs) return wrapped_function @sound_decorator def cmd(): print('command') root = tk.Tk() button = tk.Button(root, text = 'Play', command = cmd) button.pack() root.mainloop()
Cites Evil LLC · 2022-11 · Stack Overflow · on “Python Decorators | How the arguments of a function pass through a wrapper function”
In this decorators video [this video] by Corey Schafer he said the display_info function wouldn't run because it takes two arguments but wrapper_function takes 0 arguments. def decorator_function(original_function): def wrapper_function(): print('wrapper executed this before {}'.format(original_function.__name__)) return original_function() return wrapper_function @decorator_function def display(): print('display function ran') @decorator_function def display_info(name, age): print('display_info ran with arguments({},{})'.format(name, age)) display_info('John', 25) Then he adds *args and **kwargs to the wrapper function so it can take any number of arguments. def decorator_function(original_funct