js（node）实现列表的数据结构

/** @Author: wyt* @Date: ??2018-06-14 17:11:19* @Last Modified by: ??wyt* @Last Modified time: 2018-06-19 19:14:03*/// 列表用于存放数据量较少的数据结构// 当数据量较大时，不需要对其进行查找、排序的情况下，使用列表也比较方便。function List () { ???this.listSize = 0; ?// 列表长度 ???this.pos = 0; ?// 当前位置 ???this.clear = clear; // 清空列表 ???this.getLength = getLength; // 获取列表的长度 ???this.toString = toString; // 返回列表的字符串形式 ???this.getElement = getElement; // 返回当前位置的元素 ???this.insert = insert; //在指定位置后面插入元素 ???this.append =append; // 在列表的末尾添加元素 ???this.remove = remove; // 从列表中删除当前元素 ???this.front = front; // 将列表的当前位置移动到第一个元素位置 ???this.end =end; // 将列表的当前位置移动到最后一个元素位置 ???this.prev = prev; // 将列表的当前位置向前移动一位 ???this.next = next; // 将列表的当前位置向后移动一位 ???this.currentPos = currentPos; // 返回列表的当前位置 ???this.moveTo = moveTo; // 将当前位置移动到指定位置 ???this.find = find; // 获取指定元素的位置 ???this.loop = loop; // 列表的遍历器 ???this.list = []; ???function clear () { ???????this.list.length = 0; ???????this.listSize = 0; ???????this.pos = 0; ???} ???function getLength () { ???????return this.list.length; ???} ???function toString () { ???????return this.list; ???} ???function getElement () { ???????return this.list[this.pos]; ???} ???function insert (item, after) { ???????var index = this.find(after) ???????if(index){ ???????????this.list.splice(index+1, 0, item); ???????????this.listSize++; ???????????return 1; ???????} ???????return -1 ???} ???function append (item) { ???????this.list.push(item); ???????this.listSize++; ???} ???function remove (ele) { ???????for (var i=0;i<this.list.length;i++) { ???????????if(this.list[i]===ele){ ???????????????this.list.splice(i, 1); ???????????????return 1; ???????????}else{ ???????????????return -1; ???????????} ???????} ???????this.listSize--; ???????????} ???function front () { ???????this.pos = 0; ???} ???function end () { ???????this.pos = this.list.length-1; ???} ???function prev () { ???????this.pos--; ???} ???function next () { ???????this.pos++; ???} ???function currentPos () { ???????return this.pos; ???} ???function moveTo (index) { ???????this.pos = index; ???} ???function find (ele) { ???????for (var i = 0; i<this.list.length; i++) { ???????????if(this.list[i] == ele) { ???????????????return i ???????????} ???????} ???????return -1; ???} ???function loop (cb) { ???????for(this.front();this.currentPos()<this.list.length;this.next()){ ???????????var loopItem = this.getElement(); ???????????var index = this.currentPos(); ???????????(function(index, loopItem){ ???????????????cb(index, loopItem); ???????????})(index, loopItem) ???????} ???}}// var li = new List();// li.append("kevin");// li.append("tate");// li.append("pomelott");// li.loop(function(index, loopItem){// ????console.log(index, loopItem);// })const fs = require("fs");let movieListData;let movieList = new List();fs.readFile("movie.txt", "utf-8", function(err, data){ ???movieListData = data.split("\r\n"); ???movieListData.forEach(function(item){ ???????movieList.append(item); ???}) ???movieList.loop(function(index, loopItem){ ???????console.log(index, loopItem); ???})})