Decorator 2

2 decorators 1


def print_more(func):
    def wrapper(*args, **kwargs):
        print('func:', func.__name__)
        print('args:', args)
        print('kwargs:', kwargs)
        result = func(*args, **kwargs)
        print('result:', result)
        return result
    return wrapper

def print_info(func):
    def wrapper(*args, **kwargs):
        print('start')
        result = func(*args, **kwargs)
        print('end')
        return result
    return wrapper

@print_info
@print_more
def add_num(a, b):
    return a + b
    
r = add_num(10, 40)
print(r)

Execution result of two decorators 1


start
func: add_num
args: (10, 20)
kwargs: {}
result: 30
end
30

If you change the order of @print_info and @print_more The execution result is

Execution result when replaced


func: wrapper
args: (10, 40)
kwargs: {}
start
end
result: 50
50

Becomes

this is, As below It may be a little easier to understand if you write it without using @. .. ..

2 decorators 2


def print_more(func):
    def wrapper(*args, **kwargs):
        print('func:', func.__name__)
        print('args:', args)
        print('kwargs:', kwargs)
        result = func(*args, **kwargs)
        print('result:', result)
        return result
    return wrapper

def print_info(func):
    def wrapper(*args, **kwargs):
        print('start')
        result = func(*args, **kwargs)
        print('end')
        return result
    return wrapper

def add_num(a, b):
    return a + b

f = print_info(print_more(add_num))
r = f(10, 40)
print(r)

Execution result of two decorators 2


start
func: add_num
args: (10, 20)
kwargs: {}
result: 30
end
30

An image that wraps print_more in print_info. .. ..

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