Python迭代器 —— 实现for循环

Posted 2020-10-09

Python的for循环本质上就是通过不断调用next()函数实现的，例如：

 1 #_*_coding:utf-8_*_
 2 #__author__ = "csy"
 3 d = ["咖啡浆果风味拿铁","抹茶星冰乐","可可碎片星冰乐","焦糖玛奇朵","经典巧克力","咖啡密斯朵","热牛奶","东方美人","冰摩卡","卡布奇诺","美式咖啡","双果果汁"]
 4 a = iter([0,1,2,3,4,5,6,8,9,10,11])
 5 while True:
 6     try:
 7         x = next(a)
 8         print(d[x])
 9     except StopIteration:
10         break

输出：

咖啡浆果风味拿铁
抹茶星冰乐
可可碎片星冰乐
焦糖玛奇朵
经典巧克力
咖啡密斯朵
热牛奶
冰摩卡
卡布奇诺
美式咖啡
双果果汁

 

相当于：

1 #_*_coding:utf-8_*_
2 #__author__ = "csy"
3 d = ["咖啡浆果风味拿铁","抹茶星冰乐","可可碎片星冰乐","焦糖玛奇朵","经典巧克力","咖啡密斯朵","热牛奶","东方美人","冰摩卡","卡布奇诺","美式咖啡","双果果汁"]
4 for x in range(0,12):
5     print(d[x])