Decorators: Enhancing Functions with Style

Learning Objectives Define a Python function that takes another function as an argument. Explain the concept of a 'wrapper' function and its role in a decorator. Write a simple decorator from scratch. Apply a decorator to a function using the '@' syntax. By the end of of this lesson, students will be able to create a decorator that works correctly with functions that accept arguments. Identify and fix common errors in decorator implementation, such as forgetting to return the wrapper function. What if you could give any of your functions a superpower, like a force field or a special announcement, without changing its original code? 🦸✨ In this lesson, you'll learn about Decorators, a powerful advanced Python feature. Decorators are like special &#0...

TermDefinitionExample FunctionA reusable block of code that performs a specific task. You already know how to define and call functions using `def`.def greet(name): print(f'Hello, {name}!') First-Class FunctionsIn Python, functions are 'first-class citizens'. This means you can treat them just like any other variable, such as an integer or a string. You can pass them as arguments to other functions, and functions can return them.def say_hello(): return 'Hello!' greeting = say_hello print(greeting()) # This will print 'Hello!' Higher-Order FunctionA function that either takes one or more functions as arguments, or returns a function as its result. Decorators are a type of higher-order function.def do_twice(func): func() func() def say_whee(...

The Basic Decorator Pattern def decorator_name(original_function): def wrapper_function(*args, **kwargs): # 1. Code to run BEFORE the original function result = original_function(*args, **kwargs) # 2. Code to run AFTER the original function return result return wrapper_function This is the fundamental structure of any decorator. It defines an outer function (the decorator) and an inner function (the wrapper). The wrapper calls the original function and the decorator returns the wrapper. Applying a Decorator @decorator_name def my_function(): # function code here Place the '@' symbol followed by the decorator's name on the line directly above the function you want to enhance. This automatically applies the decorator's logic to your fu...