369列表/字典的分拆, unpacking

Posted 2021-02-08 alex-bn-lee

参考: python--参数列表的分拆 

当你要传递的参数已经是一个列表，调用的函数却接受分开一个个的参数，这个时候可以考虑参数列表拆分：

• 可以使用* 操作符来自动把参数列表拆开:

args=[3,6]
x=list(range(*args))
print(x)
 
-------------------输出-----------------------------
 
[3, 4, 5]

• 可以使用 ** 操作符分拆关键字参数为字典:

def parrot(voltage,state=‘a stiff‘,action=‘voom‘):
    print("-- This parrot wouldn‘t ",action)
    print("if you put ",voltage,"volts through it.")
    print("E‘s",state,"!")
 
d={"voltage":"four million", "state":"bleedin demised","action":"voom"}
 
parrot(**d)
 
-------------------输出-----------------------------
 
-- This parrot wouldn‘t  voom if you put  four million volts through it. E‘s bleedin demised !