Python decorator

What is a decorator?

A decorator is a function that takes a function and extends its functionality without modifying it explicitly 🤯

Simply giving a function some super powers.

Decorator example

def my_decorator(func):
    def wrapper():
        print("First")
        func()
        print("Last")
    return wrapper
@my_decorator
def say_hello():
    print("Hello I am line Number 2")
say_hello()
# First
# Hello I am line Number 2
# Last

Understand how decorator works

def my_decorator(func):
    def wrapper():
        print("First")
        func()
        print("Last")
    return wrapper
def say_hello():
    print("Hello I am line Number 2")

Here,

• We declare a decorator function and it takes a function as argument.
• Inside that, we write a wrapper function where operations are carried out and return the wrapper function itself.

say_hello_with_decorator = my_decorator(say_hello)
say_hello_with_decorator()
# First
# Hello I am line Number 2
# Last

Uses of decorator

• Setup logger
• Setup configuration
• Setup Error catching
• Extending common functionality for all function and classes