SOURCE

console 命令行工具 X clear
> {"value":1,"done":false}
> {"value":2,"done":false}
> {"value":3,"done":false}
> {"done":true}
>
console
const arr = [1, 2, 3];
const iterator = arr[Symbol.iterator]();

console.log(iterator.next());
console.log(iterator.next());
console.log(iterator.next());
console.log(iterator.next());