参数练习
1 def story(**kwds): 2 return('Once upon a time.there was a %(job)s called %(name)s.'%kwds) 3 4 def power(x,y,*others): 5 if others: 6 print('Received redundant parameters:'，others) 7 return pow(x,y) 8 9 def interval(start,stop=None,step=1): 10 'Imitates range() for step>0' 11 if stop is None: 12 start, stop = 0,start 13 result = [] 14 i = start 15 while i <stop: 16 result.append(i) 17 i+=step 18 return result
>>> print(story(job='king',name='Gumby'))
Once upon a time.there was a king called Gumby.
>>> print(story(name='Liang',job='leader'))
Once upon a time.there was a leader called Liang.
>>> kwds = {'name':'Morse','job':'detective'}
>>> print(story(**kwds))
Once upon a time.there was a detective called Morse.
>>> del kwds['job']
>>> print(story(job='stroke of genius',**kwds))
Once upon a time.there was a stroke of genius called Morse.
>>> power(2,3)
8
>>> power(3,2)
9
>>> power(y=3,x=2)
8
>>> params = (5,)*2
>>> power(*params)
3125
>>> power(3,3,'hello,world')
Received redundant parameters:hello,world
27
>>> interval(10)
[0, 1, 2, 3, 4, 5, 6, 7, 8, 9]
>>> interval(1,5)
[1, 2, 3, 4]
>>> power(*interval(3,7)) ###power（[3,4,5,6]）
Received redundant parameters: (5, 6)
81
