13-Python-装饰器

 1 def bar():
 2     print("in the bar")
 3 def foo():
 4     print("in the foo")
 5     bar()
 6 
 7 foo()
 8 
 9 print("----------分割线-----------")
10 
11 def foo1():
12     print("in the foo")
13     bar1()
14 def bar1():
15     print("in the bar")
16 
17 foo1()
18 
19 print("----------分割线-----------")
20 # 这样会报错
21 # def foo2():
22 #     print("in the foo")
23 #     bar2()
24 # foo2()
25 # def bar2():
26 #     print("in the bar")

 1 import time
 2 
 3 def bar1():
 4     time.sleep(3)
 5     print("in the bar")
 6 
 7 def test2(func):
 8     start_time = time.time()
 9     func()  # 相当于运行bar1()
10     stop_time = time.time()
11     print("total run time %s" %(stop_time - start_time))
12 
13 test2(bar1)  

 1 def bar2():
 2     time.sleep(3)
 3     print("in the bar2")
 4 
 5 def test3(func):
 6     print(func)
 7     return func
 8 
 9 print(test3(bar2))  # 获取的是内存地址
10 
11 res = test3(bar2)
12 res()

1 def foo():
2     print("in the foo")
3     def bar():
4         print("in the bar")
5     bar()  # 局部变量只能在其作用域内调用
6 
7 foo()

 1 x = 0
 2 def grandpa():
 3     x = 1
 4     def dad():
 5         x = 2
 6         def son():
 7             x = 3
 8             print(x)  # 最终打印结果为3
 9         son()
10     dad()
11 grandpa()

 1 import time
 2 
 3 
 4 def timer(func):
 5     def deco():
 6         start_time = time.time()
 7         func()
 8         stop_time = time.time()
 9         print("total time is %s" % (stop_time - start_time))
10     return deco  # 返回deco()的内存地址
11 
12 
13 def test1():
14     time.sleep(3)
15     print("in the test1")
16 
17 
18 def test2():
19     time.sleep(3)
20     print("in the test2")
21 
22 
23 timer(test1)  # test1的内存地址赋值给func,返回deco()的内存地址
24 print(timer(test1))  # 返回deco()的内存地址
25 test1 = timer(test1)  # 内存地址赋值给test1
26 test1()  # 相当于执行deco()
27 
28 timer(test2)
29 test2 = timer(test2)
30 test2()
31 
32 print("---------我是分隔符---------")
33 
34 
35 # 装饰器语法如下
36 @timer  # 相当于test1 = timer(test1)
37 def test1():
38     time.sleep(3)
39     print("in the test1")
40 
41 
42 @timer
43 def test2():
44     time.sleep(3)
45     print("in the test2")
46 
47 
48 test1()
49 test2()