let authors = {
		allAuthors:{
			fiction:["周","吴","郑"],
			scienceFiction:["王赵","钱孙","冯陈"],
			fantasy:["蒋沈韩杨","朱秦尤许","何吕施张"]
		},
		addres:[]
	}
	authors[Symbol.iterator] = function () {  // 自定义遍历器
		let allAuthors = this.allAuthors // this 指向的是 authors 
		let keys = Reflect.ownKeys(allAuthors) // 获取key  fiction fiction fantasy
		let values = []
		return {  // 格式如此 必须要有
			next(){ 
				if(!values.length){
					if(keys.length){
						values = allAuthors[keys[0]]
						keys.shift()
					}
				}
				return{
					done:!values.length, // 布尔值  false结束
					value:values.shift()    // value的值自定义
				}
			}
		}
	}
	let r = []
	for(let v in authors){
		r.push(v)
	}
	console.log(r)