# def wrapper(f): #     def inner(*args,**kwargs): #         print('在被装饰的函数执行之前做的事') #         res = f(*args,**kwargs) #         print('在被装饰的函数执行之后做的事') #         return res #     return inner # @wrapper            # holiday = wrapper(holiday)    这时holiday == inner # def holiday(day): #     print('全体放假%s天'%day) #     return '好开心' # ret = holiday(3) # print(ret) # def outer(*args,**kwargs): #     print(args,kwargs) #     print(*args) #     def inner(*args): #         print('inner:', args) #     inner(*args) # outer(1,2,3,4,a = 1,b = 2) # def wahaha(): #     ''' #     一个打印娃哈哈的函数 #     :return: #     ''' #     print('娃哈哈') # print(wahaha.__name__)  # 查看字符串格式的函数名 # print(wahaha.__doc__)   # document (查看函数的注释) # from functools import wraps # def wrapper(f):     # f = holiday #     @wraps(f)                               # 加上这句话之后, holiday 就是holiday 不是inner了 #     def inner(*args,**kwargs): #         print('在被装饰的函数执行之前做的事') #         res = f(*args,**kwargs) #         print('在被装饰的函数执行之后做的事') #         return res #     return inner # @wrapper            # holiday = wrapper(holiday)    这时holiday == inner  ，这时还没加上面那句话 # def holiday(day): #     print('全体放假%s天'%day) #     return '好开心' # ret = holiday(3) # print(holiday.__name__)     # 输出inner，加了上面那句话之后输出 holiday # ---------------------------------------------------------------------------------------------------- # # 带参数的装饰器 # 500个函数 # # import time # FLAG = True # def timmer_out(flag): #     ''' #     计算机函数执行时间 #     :param flag:flag为真时,运行这个函数,为假时不运行 #     :return: #     ''' #     def timmer(func): #         def inner(*args,**kwargs): #             if FLAG: #                 start_time = time.time() #                 ret = func(*args,**kwargs) #                 end_time = time.time() #                 print(end_time - start_time) #                 return ret #             else: #                 ret = func(*args, **kwargs) #                 return ret #         return inner #     return timmer # @timmer_out(FLAG)           # 先调用timmer_out(FLAG)，返回的结果为timmer, 加了@ 之后就等于 @timmer,就等于wahaha = timmer(wahaha) # # 上个式子等价于： # # timmer = timmer_out(FLAG) # #@timmer # # def wahaha(): #     time.sleep(0.1) #     print('娃哈哈') # @timmer_out(FLAG) # def erguotou(): #     time.sleep(0.1) #     print('二锅头') # wahaha() # erguotou() # 多个装饰器装饰一个函数 # # def wrapper1(func):     # func --> f #     def inner1(): #         print('wrapper1,before func') #         func()      # f #         print('wrapper1,after func') #     return inner1 # # def wrapper2(func):     # func --> inner1 #     def inner2(): #         print('wrapper2, before func') #         func()      # 其实是 inner1() #         print('wrapper2, after func') #     return inner2 # # @wrapper2   # f = wrapper2(f) --> wrapper2(inner1), 返回的inner2，故 f == inner2 # @wrapper1   # f = wrapper1(f) 返回的inner1，故 f == inner1 # # # 先找最近的函数,wrapper2没找到, wrapper1先找的f()，然后wrapper2又找的 # def f(): #     print('in f') # # f() # --> inner2() # ---------------------------------------------------------------------------------- # # 三个 def wrapper1(func):     def inner1():         print('wrapper1,before func')         ret = func()         print('wrapper1,after func')         return ret     return inner1 def wrapper2(func):     def inner2():         print('wrapper2, before func')         ret = func()         print('wrapper2, after func')         return ret     return inner2 def wrapper3(func):     def inner3():         print('wrapper3, before func')         ret = func()         print('wrapper3, after func')         return ret     return inner3 @wrapper3 @wrapper2 @wrapper1 def f():     print('in f')     return '哈哈哈' print(f()) # 记录用户的登录情况 and 计算这个函数的执行时间