Why Are Decorator Functions Designed In The Way They Are?

It was bothering me for a long time. Why are decorator functions designed like that, they seem to me over complicated. Let's take for example something like this: def dec(f): d

Solution 1:

A decorator should return a function not the result of a function. In your first example, it returns a function ... In the second, it returns whatever your function f returns. - julien

1. Why second sample does not works?

   Because you are calling the function on the return, you are not returning a function.

2. Why args,kwargs are "magically" appears if we are using a nested function?

   They don't appear magically, we are declaring them, as in:

   defdeco(*args, **kwargs):
   

   These are generic, and will match any function signature (argument list). You don't have to call them args and kwargs, that's just a convention, you could call them sharon and tracy.

3. What can i do, to make 2nd sample work? Except nesting another function, ofcourse.

   Well you don't say what you expect the 2nd sample to do. But I guess to turn it into a decorator then:

   def func(f):
       return f
   

   But that's not doing a lot!

By the way, it is usually a bad idea to override an existing Python builtin (sum) - you have to have a very good reason for that. - cdarke

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