Decorators with arguments in Python

If you've been working with Python for a while, you've probably already encountered decorators - these handy tools that allow you to modify the behavior of functions or classes with minimal code. But did you know that decorators can also take arguments? This powerful feature allows you to create smarter, more versatile decorators that can be customized for different use cases. In this Python tutorial, we'll dive into the world of decorators with arguments, exploring how they work, how to create them, and how to use them to supercharge your Python code. 

Decorators with arguments :

• Python decorators can also take arguments, 
• This can be useful when you want to customize the behavior of a decorator for different use cases.
• To add arguments to a decorator, you need to define a nested function that takes the arguments and returns the actual decorator function.

Creating decorators with arguments

• In the code sample below we'll create a decorator with arguments
• Code Sample :

def greeting_decorator(greeting):
   
   def my_decorator(func):
       
       def wrapper_function(*args, kwargs):
           print(greeting)
           result = func(*args, kwargs)
           return result
       
       return wrapper_function
   
   return my_decorator

Explanation:

• In this example, the  greeting_decorator  is a function that takes a  greeting  argument 
• It returns a decorator function  my_decorator .
• The my_decorator is a nested function that takes a function   func()  as an argument 
• It returns a wrapped function   wrapper_function  that prints the greeting, calls the original function, 
  and returns its result.

Using decorators with arguments

• In the code sample below we'll see how we can use the decorator that we created in previous section.
• Code Sample :

@greeting_decorator("Welcome to the party!")
def my_function(name):
   print(f"Hello, {name}!")

my_function("Alice")
my_function("Bob")


Output:
Welcome to the party!
Hello, Alice!
Welcome to the party!
Hello, Bob!

Explanation:

• In this example, we use the  greeting_decorator  to create a decorator that displays a custom greeting before calling the decorated function.
• We use the  @  symbol to apply the  greeting_decorator  decorator to the  my_function  function and pass the "Welcome to the party!" greeting as an argument.
• When we call  my_function("Alice") , the output shows the greeting followed by the function's output with the given name parameter.
• Similarly, when we call  my_function("Bob") , the output shows the greeting followed by the function's output with the given name parameter.