Python full stack development from primer to discard adorner function

1. Function name can be used as parameter of function

1 Import Time2 defTimmer (func):3     #function names can be used as arguments to functions4     definner ():5Start =time.time ()6 func ()7End =time.time ()8         Print(End-start)9     returnInnerTen  One defhahaha (): ATime.sleep (0.1) -     Print('AAAA') -  the hahaha () -  - Output Results -Aaaa

2, if we can not modify the function of the call mode, and can not modify the original code, how to do it

1 Import Time2 defTimmer (func):3     #function names can be used as arguments to functions4     definner ():5Start =time.time ()6 func ()7End =time.time ()8         Print(End-start)9     returnInnerTen  One defhahaha (): ATime.sleep (0.1) -     Print('AAAA') -  thehahaha = Timmer (hahaha)#The address of the Timmer function is given to hahaha and then the call is made - hahaha () -  - AAAA +0.10033607482910156

# hahaha = Timmer (hahaha) #timmer函数的地址给了hahaha
# hahaha () #实际上执行的是timmer

3. Function Transfer parameter

1 defTimmer (func):#---> Hahaha2     defInner (*args,**kwargs):#dynamic parameters received from KKK and compressed into tuples3         #args = = (Kwargs) = = {}4         #*args = = **kwargs = = a =1,b = 25Func (*args,**kwargs)#---"KKK #func把值传给kkk并还原, is actually the compression value of the dynamic parameters received before decompression, return to the KKK function6     returnInner7 8 9 defKKK (A, b):Ten     Print(a) One  AKKK = Timmer (KKK)#the Func in the Timmer function is the KKK function and returns the inner function to KKK -KKK (ON)#the KKK function calls and passes the parameter to the inner (dynamic parameter *args), -  the1

Parameters
#实参: Arguments passed in when a function is called
#形参
#位置参数: value must be passed

1 def aaa (A, B): 2 Print (A, b) 3 aaa (+)

#默认参数: Can not pass

1 def BBB (x=10):      # default parameters are not uploaded parameters, with the default parameters, upload the words will use the upload parameters.  2print(x)3#x =4#x = 20 

#动态参数

1 def CCC (*args):#1,2,3,4,5     #*args  2print(args)  34 CCC (1,2,3,4,5)# pass parameters by location

Extract the parameters

1 def CCC (*args):#1,2,3,4,52     print(args)34  #CCC (1,2,3,4,5) #按位置传参数 56 t = (1,2,3,4,5)7 # ((1, 2, 3, 4, 5),) 8 CCC (*T)  #(1, 2, 3, 4, 5)   #解压

Pass Key by keyword

1 def ddd (**kwargs):   #Kwargs receives the parameters and then stores the 2print in a dictionary     (Kwargs )34'a'b')#  pass parameters by keyword

Scatter assignment

1 defCCC (*args):2     Print('CCC:', args)#(1,2,3,4,5)3     defInner (a,b,c,d,e):4         Print('Inner', A,b,c,d,e)5Inner (*args)#* (1,2,3,4,5) Scattered6 7 defInner (a,b,c,d,e):#receive the extracted parameters and assign them to each value8     Print('Inner', A,b,c,d,e)9CCC (1,2,3,4,5)TenInner (1,2,3,4,5)

4. Grammar sugar

1 defTimmer (func):#---> JJJ2     defInner (*args,**Kwargs):3ret = func (*args,**kwargs)#--->ret = jjj ()4         Print(ret)5         returnret6     returnInner7 8@timmer#JJJ = Timmer (JJJ) syntax sugar9 defjjj ():Ten     return123 One  A  - jjj () #ret = JJJ () -  the  - Output Results -123

5. Adorner function

#装饰器的本质: Closure function
#功能: In the case of not changing the way the original function is called, the extension function is added before and after this function
def Timmer (func):
def inner (*args,**kwargs):
"' Add extension code before function call '
ret = func (*args,**kwargs)
"' Add extension code after function call '
return ret
return inner
Open and closed principle of #设计模式 principle
#对扩展是开放的
#对修改是封闭的

6, adorner decoration two functions

1 defWrapper (func):#Decoration2     defInner (*args,**Kwargs):3 4ret = func (*args,**Kwargs)5 6         returnret7     returnInner8 9@wrapper#AAA = wrapper (AAA)Ten defaaa (): One     Print('ASGHKSDLHF') A  -@wrapper#BBB = wrapper (BBB) - defBBB (): the     Print('ASGHKSDLHF') -  -  - aaa () + BBB () -  +  A #Output Result: at #ASGHKSDLHF - #ASGHKSDLHF

7.

Python full stack development from primer to discard adorner function