Describes a user-defined Iterator that is also iterable.
返回此对象的可迭代迭代器。
Returns an iterable iterator for this object.
移至迭代器的下一个值。
Moves to the next value in the iterator.
Optional
结束迭代器并返回值。
Ends the iterator and returns a value.
在迭代器中引发错误。
Throws an error in the iterator.
Describes a user-defined Iterator that is also iterable.