Decorators

[yksingh1097]

I was going through a tutorial and encountered this code. Can anybody please make me understand the control flow of this code? Like which line is executed first and what is being passed as argument. I apologize if it is silly but i am mid newbie.

I know that when control encounters @decorator_function, it treat it as the beneath function being passed as argument to the decorator function but then it means that

1	original_function=display

or

1	original_function=display(): print('display function ran')

or what else.
And also when wrapper function is returned, than does that mean or can we say that display defination is replaced by wrapper function

1 2 3

@decorator_function def display():     wrapper_function

OR

1 2	@decorator_function wrapper_function

Please explain...

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def decorator_function(original_function):     def wrapper_function():         print('wrapper executed this before {}'.format(original_function.__name__))         return original_function()     return wrapper_function   @decorator_function def display():     print('display function ran')   #display()   if __name__ == '__main__':     display()

Output:
wrapper executed this before display
display function ran

I understand that the above python code and the below code both are same. But need to understand the proper control flow.

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def decorator_function(original_function):     def wrapper_function():         print('wrapper executed this before {}'.format(original_function.__name__))         return original_function()     return wrapper_function   #@decorator_function def display():     print('display function ran')   #display()   if __name__ == '__main__':     display()     dd=decorator_function(display)     dd()

[Gribouillis]

The only thing to understand is that

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@spam def eggs():     print('ham')

is equivalent to

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def eggs():     print('ham') eggs = spam(eggs)

[yksingh1097]

The only thing to understand is that

1 2 3

@spam def eggs():     print('ham')

is equivalent to

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def eggs():     print('ham') eggs = spam(eggs)

Okay thanks Sir. I get it .