Python functools.wraps Decorator Module

#-*-coding=utf-8-*-__author__='Piay'ImportTime , Functoolsdeffoo ():" "define a normal function: return:" "    Print 'This is foo'foo ()" "here, if we need to look at the function execution time, modify it to:" "deffoo1 (): Start_time=Time.clock ()Print 'This is foo1'End_time=Time.clock ()Print 'The execution time is:', End_time-start_timefoo1 ()" "if our other functions also require execution time, or if the function does not require execution time, then we need to copy it to the other functions. That's the worst way." "defFoo3 ():Print 'This is Foo3'defTimeit (func):" "we could consider redefining a function Timeit, passing the reference to Foo, and then calling Foo in Timeit and timing it so that we can achieve the purpose of not altering the Foo definition:p aram Func: The function passed in: return: " "start_time=Time.clock () func () End_time=Time.clock ()Print 'used:', End_time-Start_timetimeit (Foo3)" "This writes the code that modifies the calling section. That's what we call it: Foo3 (), now Timeit (foo), so if Foo is called at N, you have to change the code in the N place. Or, to be more extreme, consider that the code in which it is called cannot modify the situation, for example: This function is something you give to someone else. " "" "think of a way to not modify the code of the call, if you do not modify the calling code, it means that calling Foo () requires the effect of calling Timeit (foo). We can think of assigning Timeit to Foo, but Timeit seems to have a parameter ... Think of ways to unify the parameters! If Timeit (foo) does not directly produce a call effect, but instead returns a function that is consistent with the Foo argument list ... It's good to have the return value of Timeit (foo) assigned to Foo, and then the code that calls Foo () doesn't have to be modified at all! " "defFoo4 ():Print 'This is Foo4'#Define a timer, pass in one, and return another method with the timer feature attacheddefTIMEIT4 (func):#define an inline wrapper function that adds a timing function to the incoming function    defwrapper (): Start_time=Time.clock () func () End_time=Time.clock ()Print 'used:', End_time-start_time#returns the Wrapped function    returnWrapperfoo_1=Timeit (Foo4)" "The above code is like an adorner, which can be modified as follows:" "@timeit4#adding this line to the definition is exactly equivalent to the other write foo = Timeit (foo)deffoo5 ():Print 'This is foo5'Foo5 ()" "-----------------------------------------------functions using the Functools.wraps (func) Adorner" "defTimeit_3_for_wraps (func): @functools. Wraps (func)defwrapper (): Start=Time.clock () func () End=Time.clock ()Print 'used:', end-StartreturnWrapper@timeit_3_for_wrapsdefFoo6 ():Print 'This is Foo6'Foo6 ()

Python functools.wraps Decorator Module