Today,We will talk some about the argument and arguments ...

#!/usr/bin/pythondef fun(*args):    for value in args:        print valueif __name__ == '__main__':        fun(11,22,33,44,55)

 

What is type of (*args) ?

Do you really want to know ,just keep read ...

#!/usr/bin/pythondef fun(*args):    print type(args)    for value in args:        print valueif __name__ == '__main__':        fun(11,22,33,44,55)

 

Okay,We know the (*args ) just a tuple type?

so,we can input a tuple as argument ...

#!/usr/bin/pythondef fun(*args):    print type(args)    for value in args:        print valueif __name__ == '__main__':        my_tuple=(11,22,33,44,55)    fun(my_tuple)

 

Oh,What happened ? The result is no what we expect ...

See the below code,you will find the answer ...

#!/usr/bin/pythondef fun(*args):    print type(args)    for value in args:        print valueif __name__ == '__main__':        my_tuple=(11,22,33,44,55)    fun(*my_tuple)

 

Okay,see we got the result what we expect ...

 

Good,time to talk (**kwargs)

#!/usr/bin/pythondef fun(**kwargs):        print type(kwargs)    for key in kwargs:        print 'key: ',key,'value: ',kwargs[key]    if __name__ == '__main__':    fun(name='Frank',age=23,school='IMUT')

 

 

Of course,you can input a dict as argument,but Don't forget the (**) again ...

If you really want to forget (**) ,like the below code ...

#!/usr/bin/pythondef fun(**kwargs):        print type(kwargs)    for key in kwargs:        print 'key: ',key,'value: ',kwargs[key]    if __name__ == '__main__':    my_dict={
   'name':'Frank','age':23,'school':'IMUT'}    fun(my_dict)

 

You will got a error like the below :

 

So ,You don't really want to do it again ,right ...haha

#!/usr/bin/pythondef fun(**kwargs):        print type(kwargs)    for key in kwargs:        print 'key: ',key,'value: ',kwargs[key]    if __name__ == '__main__':    my_dict={
   'name':'Frank','age':23,'school':'IMUT'}    fun(**my_dict)

 

Okay ! see the right result :

 

But,You may ask when we should use **kwargs ...

and where use it ...

Okay,see example 01 below:

#!/usr/bin/pythonclass Student(object):        def __init__(self,name):        super(Student,self).__init__()        self.name = nameif __name__ == '__main__':        s = Student('Frank')    print s.name

 

Okay,keep going ..

sometime ,you may see the below argument usage ...

if __name__ == '__main__':        s = Student('Frank',age=23,id=0011,phone=12345)

But,how it is work inside ...

see the below code ...

#!/usr/bin/pythonclass Student(object):        def __init__(self,name,**kwargs):        super(Student,self).__init__()        self.name = name        for k in kwargs:            setattr(self,k,kwargs[k])if __name__ == '__main__':        s = Student('Frank',age=23,id=0011,phone=12345)    print s.name    print s.age    print s.id    print s.phone

Thank you !