doc: update javascript.md.
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@ -386,18 +386,18 @@ sum(3, 6); // 9
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### 匿名函数
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```javascript
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// Named function
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// 命名函数
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function rocketToMars() {
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return 'BOOM!';
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}
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// Anonymous function
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// 匿名函数
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const rocketToMars = function() {
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return 'BOOM!';
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}
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```
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### 箭头函数 (ES6)
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<!--rehype:wrap-class=row-span-2-->
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<!--rehype:wrap-class=row-span-3-->
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#### 有两个参数
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@ -590,6 +590,48 @@ for (let j = 0; j < 3; j++) {
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JavaScript Arrays
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----
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### 方法
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<!--rehype:wrap-class=row-span-6-->
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:- | :-
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:- | :-
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`Array.from()` | 类似数组对象创建一个新的 [#](https://developer.mozilla.org/zh-CN/docs/Web/JavaScript/Reference/Global_Objects/Array/from)
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`Array.isArray()` | 值是否是一个 Array [#](https://developer.mozilla.org/zh-CN/docs/Web/JavaScript/Reference/Global_Objects/Array/isArray)
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`Array.of()` | 创建一个新数组示例 [#](https://developer.mozilla.org/zh-CN/docs/Web/JavaScript/Reference/Global_Objects/Array/of)
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`.at()` | 返回值索引对应的元素 [#](https://developer.mozilla.org/zh-CN/docs/Web/JavaScript/Reference/Global_Objects/Array/at)
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`.concat()` | 合并两个或多个数组 [#](https://developer.mozilla.org/zh-CN/docs/Web/JavaScript/Reference/Global_Objects/Array/concat)
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`.copyWithin()` | 浅复制替换某个位置 [#](https://developer.mozilla.org/zh-CN/docs/Web/JavaScript/Reference/Global_Objects/Array/copyWithin)
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`.entries()` | 新的 Array Iterator 对象 [#](https://developer.mozilla.org/zh-CN/docs/Web/JavaScript/Reference/Global_Objects/Array/entries)
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`.every()` | 是否能通过回调函数的测试 [#](https://developer.mozilla.org/zh-CN/docs/Web/JavaScript/Reference/Global_Objects/Array/every)
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`.fill()` | 固定值填充一个数组中 [#](https://developer.mozilla.org/zh-CN/docs/Web/JavaScript/Reference/Global_Objects/Array/fill)
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`.filter()` | 返回过滤后的数组 [#](https://developer.mozilla.org/zh-CN/docs/Web/JavaScript/Reference/Global_Objects/Array/filter)
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`.find()` | 第一个元素的值 [#](https://developer.mozilla.org/zh-CN/docs/Web/JavaScript/Reference/Global_Objects/Array/find)
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`.findIndex()` | 第一个元素的索引 [#](https://developer.mozilla.org/zh-CN/docs/Web/JavaScript/Reference/Global_Objects/Array/findIndex)
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`.findLast()` | 最后一个元素的值 [#](https://developer.mozilla.org/zh-CN/docs/Web/JavaScript/Reference/Global_Objects/Array/findLast)
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`.findLastIndex()` | 最后一个元素的索引 [#](https://developer.mozilla.org/zh-CN/docs/Web/JavaScript/Reference/Global_Objects/Array/findLastIndex)
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`.flat()` | 扁平化嵌套数组 [#](https://developer.mozilla.org/zh-CN/docs/Web/JavaScript/Reference/Global_Objects/Array/flat)
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`.flatMap()` | 与 flat 相同 [#](https://developer.mozilla.org/zh-CN/docs/Web/JavaScript/Reference/Global_Objects/Array/flatMap)
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`.forEach()` | 升序循环执行 [#](https://developer.mozilla.org/zh-CN/docs/Web/JavaScript/Reference/Global_Objects/Array/forEach)
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`.includes()` | 是否包含一个指定的值 [#](https://developer.mozilla.org/zh-CN/docs/Web/JavaScript/Reference/Global_Objects/Array/includes)
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`.indexOf()` | 找到给定元素的第一个索引 [#](https://developer.mozilla.org/zh-CN/docs/Web/JavaScript/Reference/Global_Objects/Array/indexOf)
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`.join()` | 数组链接成一个字符串 [#](https://developer.mozilla.org/zh-CN/docs/Web/JavaScript/Reference/Global_Objects/Array/join)
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`.keys()` | 每个索引键 [#](https://developer.mozilla.org/zh-CN/docs/Web/JavaScript/Reference/Global_Objects/Array/keys)
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`.lastIndexOf()` | 给定元素的最后一个索引 [#](https://developer.mozilla.org/zh-CN/docs/Web/JavaScript/Reference/Global_Objects/Array/lastIndexOf)
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`.map()` | 循环返回一个新数组 [#](https://developer.mozilla.org/zh-CN/docs/Web/JavaScript/Reference/Global_Objects/Array/map)
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`.pop()` | `删除`最后一个元素 [#](https://developer.mozilla.org/zh-CN/docs/Web/JavaScript/Reference/Global_Objects/Array/pop)
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`.push()` | 元素`添加`到数组的末尾 [#](https://developer.mozilla.org/zh-CN/docs/Web/JavaScript/Reference/Global_Objects/Array/push)
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`.reduce()` | 循环函数传递当前和上一个值 [#](https://developer.mozilla.org/zh-CN/docs/Web/JavaScript/Reference/Global_Objects/Array/Reduce)
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`.reduceRight()` | 类似 `reduce` 从右往左循环 [#](https://developer.mozilla.org/zh-CN/docs/Web/JavaScript/Reference/Global_Objects/Array/ReduceRight)
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`.reverse()` | 数组元素的位置颠倒 [#](https://developer.mozilla.org/zh-CN/docs/Web/JavaScript/Reference/Global_Objects/Array/reverse)
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`.shift()` | `删除`第一个元素 [#](https://developer.mozilla.org/zh-CN/docs/Web/JavaScript/Reference/Global_Objects/Array/shift)
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`.slice()` | `提取`元素 [#](https://developer.mozilla.org/zh-CN/docs/Web/JavaScript/Reference/Global_Objects/Array/slice)
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`.some()` | 至少有一个通过测试函数 [#](https://developer.mozilla.org/zh-CN/docs/Web/JavaScript/Reference/Global_Objects/Array/some)
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`.sort()` | 元素进行排序 [#](https://developer.mozilla.org/zh-CN/docs/Web/JavaScript/Reference/Global_Objects/Array/sort)
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`.splice()` | `删除`或`替换`或`添加`元素 [#](https://developer.mozilla.org/zh-CN/docs/Web/JavaScript/Reference/Global_Objects/Array/splice)
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`.toLocaleString()` | 字符串表示数组中的元素 [#](https://developer.mozilla.org/zh-CN/docs/Web/JavaScript/Reference/Global_Objects/Array/toLocaleString)
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`.toString()` | 返回字符串 [#](https://developer.mozilla.org/zh-CN/docs/Web/JavaScript/Reference/Global_Objects/Array/toString)
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`.unshift()` | 元素`添加`到数组的`开头` [#](https://developer.mozilla.org/zh-CN/docs/Web/JavaScript/Reference/Global_Objects/Array/unshift)
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`.values()` | 返回新的 ArrayIterator 对象 [#](https://developer.mozilla.org/zh-CN/docs/Web/JavaScript/Reference/Global_Objects/Array/values)
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### 数组
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@ -652,24 +694,24 @@ console.log(fruits); // ["apple", "dew"]
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### 方法 .shift()
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```javascript
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let cats = ['Bob', 'Willy', 'Mini'];
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cats.shift(); // ['Willy', 'Mini']
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const array1 = [1, 2, 3];
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const firstElement = array1.shift();
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console.log(array1); // 输出: Array [2, 3]
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console.log(firstElement); // 输出: 1
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```
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**从头删除**一个项目并返回已删除的项目。
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### 方法 .unshift()
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### 方法 .some()
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```javascript
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let cats = ['Bob'];
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// => ['Willy', 'Bob']
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cats.unshift('Willy');
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// => ['Puff', 'George', 'Willy', 'Bob']
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cats.unshift('Puff', 'George');
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```js
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const array = [1, 2, 3, 4, 5];
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// 检查元素是否为偶数
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const even = (element) => element % 2 === 0;
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console.log(array.some(even));
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// 预期输出: true
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```
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将项目**添加到开头**并返回新的数组长度。
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### 方法 .concat()
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```javascript
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@ -685,6 +727,45 @@ numbers.concat(newFirstNumber)
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如果你想避免改变你的原始数组，你可以使用 concat。
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### 方法 .splice()
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```javascript
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const months = ['Jan', 'March'];
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months.splice(1, 0, 'Feb');
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// 在索引 1 处插入
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console.log(months);
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// 预期输出: Array ["Jan", "Feb", "March"]
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months.splice(2, 1, 'May');
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// 替换索引 2 处的 1 个元素
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console.log(months);
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// 预期输出: Array ["Jan", "Feb", "May"]
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```
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### 方法 .unshift()
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```javascript
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let cats = ['Bob'];
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// => ['Willy', 'Bob']
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cats.unshift('Willy');
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// => ['Puff', 'George', 'Willy', 'Bob']
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cats.unshift('Puff', 'George');
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```
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将项目**添加到开头**并返回新的数组长度。
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### 方法 .filter()
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```javascript
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const words = ['js', 'java', 'golang'];
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const result = words.filter(word => {
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return word.length > 3
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});
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console.log(result);
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// 预期输出: Array ["java", "golang"]
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```
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JavaScript 循环
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----
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@ -998,19 +1079,16 @@ console.log(age); // '22'
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```javascript
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const person = {
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firstName: "Matilda",
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age: 27,
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hobby: "knitting",
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goal: "learning JavaScript"
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};
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delete person.hobby; // or delete person[hobby];
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delete person.hobby; // 或 delete person['hobby'];
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console.log(person);
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/*
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{
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firstName: "Matilda"
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age: 27
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goal: "learning JavaScript"
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}
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*/
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} */
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```
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### 对象作为参数
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