Python advanced "Nineth" decorator

What is an adorner?

The adorner itself is a function and adds additional functionality to other functions

The principle of adorners: 1. Do not modify the source code of the Decorated object 2. do not modify the calling method of the decorated object
Adorner = higher order function + function nesting + closure

# Res=timmer (Test) #返回的是wrapper的地址 # res () #执行的是wrapper ()

# Test=timmer (test) #返回的是wrapper的地址 # test () #执行的是wrapper ()

# @timmer is equivalent to Test=timmer (test)

# #搭一个高阶函数与函数嵌套的框架 # def Timmer (func): #     def wrapper (): #         Print (func) #         func () #     return Wrapperimport Timedef Timmer (func):    def wrapper ():        start_time=time.time ()        # Print (func)        Res=func () #由于执行新获得的test , so execute wrapper,func as a local variable, not currently, then go to the previous layer to find, that is, test, run test        stop_time = Time.time ()        print (' Run time is%s '% (Stop_time- start_time))        #wrapper里没有返回值, so no matter how the test is changed, the return value is None return        res# since Func runs the test, the value of Func is assigned to Res, Return res is the return value of test    wrapper@timmer# equivalent to test = Timmer (test) #把test函数作为参数传给timmer, execution Timmer gets the return value wrapper, and assign it to testdef test ():    time.sleep (3)    print (' Test run complete ') return    ' This is the return value of test ' test () #执行新的test, The actual execution is wrapper, which is to not change the way test is called

Python advanced "Nineth" decorator