python之装饰器

装饰器:　　

 1 import time
 2 def cal(l):
 3     start_time=time.time()
 4     res=0
 5     for i in l:
 6         time.sleep(0.1)
 7         res+=i
 8     stop_time = time.time()
 9     print('函数的运行时间是%s' %(stop_time-start_time))
10     return res
11 
12 print(cal(range(100)))

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装饰器预演:

 1 import time
 2 def timmer(func):
 3     def wrapper(*args,**kwargs):
 4         start_time=time.time()
 5         res=func(*args,**kwargs)
 6         stop_time = time.time()
 7         print('函数运行时间是%s' %(stop_time-start_time))
 8         return res
 9     return wrapper
10 @timmer
11 def cal(l):
12     res=0
13     for i in l:
14         time.sleep(0.1)
15         res+=i
16     return res
17 
18 res=cal(range(10))
19 print(res)

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高阶函数:

　　1.函数接收的参数是一个函数名
　　2.函数的返回值是一个函数名
　　3.满足上述条件任意一个,都可称之为高阶函数

 1 例1:
 2 import  time
 3 def foo():
 4     time.sleep(1)
 5     print('你好啊玉哥')
 6 
 7 def tests(func):
 8     start_time = time.time()
 9     func()
10     stop_time = time.time()
11     print('函数运行时间是%s'%(stop_time-start_time))
12 # foo()
13 tests(foo)

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1 例2:
2 def foo1():
3     print('from the foo1')
4 def test(func):
5     return func
6 
7 ress = test(foo1)
8 ress()

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1 foo1 = test(foo1)
2 foo1()

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函数嵌套:　

1 def father1(auth_type):
2     def son():
3         def grandson():
4             print('我的爷爷是%s'%auth_type)
5         grandson()
6     son()
7 father1('sqy')

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