a=[12,23,23,34] b=next(a) # next(a)j就等于a.__next__() print(b) # 输出 TypeError: 'list' object is not an iterator a=[12,23,23,34] a=iter(a)# iter(a)就等于a.__iter__() print(next(a)) print(next(a)) print(next(a)) #输出 12 23 23
a=(i for i in range(1000) ) print(next(a)) print(next(a)) print(next(a)) # 输出 0 1 2 #生成器函数: def d (c): for i in range(c): yield i a= d(12) print(next(a)) print(next(a)) print(next(a)) print(next(a)) #输出 0 1 2 3