3.3.4 序列操作符
处理序列的操作符可以分为4组:建立序列、搜索元素、访问内容以及从序列删除元素。
from operator import *
a = [1,2,3]
b = ['a','b','c']
print('a =',a)
print('b =',b)
print('\nConstructive:')
print(' concat(a,b):',concat(a,b))
print('\nSearching:')
print(' contains:(a,1) :',contains(a,1))
print(' contains:(b,"d"):',contains(b,"d"))
print(' countOf(a,1) :',countOf(a,1))
print(' countOf(b,"d") :',countOf(b,"d"))
print(' indexOf(a,5) :',indexOf(a,1))
print('\nAccess Items:')
print(' getitem(b,1) :',
getitem(b,1))
print(' setitem(b,slice(1,3) :',
getitem(b,slice(1,3)))
print(' setitem(b,1,"d") :',end=' ')
setitem(b,1,"d")
print(b)
print(' setitem(a,slice(1,3),[4,5]) :',end=' ')
setitem(a,slice(1,3),[4,5])
print(a)
print('\nDestructive:')
print(' delitem(b,1) :',end=' ')
delitem(b,1)
print(b)
print(' delitem(a,slice(1,3)):',end=' ')
delitem(a,slice(1,3))
print(a)
其中一些操作符(如setitem()和delitem())会原地修改序列,而且不返回任何值。
运行结果: