python 自定义 list

class MyList(object):

    def __init__(self):
        self.items = []

    def __iter__(self):
        return MyListIterator(self.items)

    def addItem(self, item):
        self.items.append(item)
        print("保存了：", item)


class MyListIterator(object):

    def __init__(self, items):
        self.items = items
        self.index = 0

    def __iter__(self):
        pass

    def __next__(self):
        if self.index < len(self.items):
            data = self.items[self.index]
            self.index += 1
            return data
        else:
            raise StopIteration


if __name__ == '__main__':
    my_list = MyList()
    my_list.addItem("张飞")
    my_list.addItem("关羽")
    my_list.addItem("刘备")
    my_list.addItem("郭嘉")

    m_iter=iter(my_list)
    x=next(m_iter)
    print(x)

    for value in my_list:
        print(value)

迭代器_斐波那契数列.py

class Fibnacci(object):

    def __init__(self, num):
        self.num = num
        self.a = 1
        self.b = 2
        self.current_index = 0

    def __iter__(self):
        return self

    def __next__(self):
        if self.current_index < self.num:
            data = self.a
            self.a, self.b = self.b, self.a + self.b
            self.current_index += 1
            return data
        else:
            raise StopIteration


if __name__ == '__main__':
    fib = Fibnacci(5)

    print(next(fib))
    print(next(fib))
    print(next(fib))
    print(next(fib))
    print(next(fib))
    print(next(fib))
    print(next(fib))
    print(next(fib))

    # print("")
    #
    # for fibc in fib:
    #     print(fibc)