eg1: Can args and kwargs be printed, what is the result of printing?
def func(*args,**kwargs):
print(args)
print(kwargs)
func (1,2,3,4, sex = 'ols', male = 'chuchu')
print result: tuples and dictionaries
Interpretation: The args print result is the tuple, and kwargs prints the result dictionary.
eg2: Positional parameters, what is the order of parameters received by args?
def func(a,b,c,*args):
print(a)
print(b)
print(c)
print(args,type(args))
func (1,2, 'alex')
print result
Interpretation: First print the positional parameters, then print the args. If you put *args first, then a, b, and c cannot receive the value and report an error.
eg3 What is the order of receiving parameters for positional parameters, args, default parameters?
def func(a,b,c,sex='nan',*args):
print(a)
print(b)
print(c)
print(sex)
print(args,type(args))
func(1,2,'alex','wusir','ritian')
print result
Interpretation: first position, then args, and finally default parameters, otherwise the default parameters are overwritten, like the one above, sex='nan' is overwritten directly and cannot be printed.
positional arguments, *args, default arguments, **kwargs
Magic operation:
def func(*args):
print(args)
li = [1,2,3]
l2 = [4,5,6]
func(li) #Output result: ([1, 2, 3],)
func(*li) #Output result: (1, 2, 3)
func(*li,l2) #Output result: (1, 2, 3, [4, 5, 6])
func(*li,*l2) #Output result: (1, 2, 3, 4, 5, 6)