Python Tutorial: Decorator Pattern 🎯

Welcome to CodeYourCraft! Today, we're diving into the fascinating world of Python Decorators. Let's get started! 🎉

What are Decorators? 📝

Decorators in Python are a design technique that allows you to add new functionality to an existing object (function or class) without modifying its source code. They are a powerful tool that helps in writing reusable and modular code.

Why Decorators? 💡

Decorators help in organizing code, making it more readable, and reusable. They can be used for logging, caching, or adding additional behavior to existing functions or classes.

How to Create a Decorator? 🎯

A decorator is a special type of function that takes another function as an argument and returns a new function with added behavior. Let's create a simple example:

python

def my_decorator(func):
    def wrapper(*args, **kwargs):
        print("Something is happening before the function is called.")
        func(*args, **kwargs)
        print("Something is happening after the function is called.")
    return wrapper

@my_decorator
def say_hello():
    print("Hello, World!")

say_hello()

In this example, my_decorator is a decorator that takes the say_hello function as an argument and returns a new function (wrapper). The @my_decorator syntax is used to apply the decorator to the say_hello function.

Practical Example 💡

Let's create a decorator that logs the time taken by a function to execute:

python

import time

def timer(func):
    def wrapper(*args, **kwargs):
        start_time = time.time()
        result = func(*args, **kwargs)
        end_time = time.time()
        print(f"Time taken by {func.__name__} to execute: {end_time - start_time} seconds")
        return result
    return wrapper

@timer
def factorial(n):
    if n == 0:
        return 1
    return n * factorial(n-1)

print(factorial(5))

Quiz Time! 🎯

Stay tuned for more exciting lessons on Python! Happy coding! 🚀