64 lines
2.3 KiB
Markdown
64 lines
2.3 KiB
Markdown
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---
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id: 587d7b8a367417b2b2512b4c
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title: Use Destructuring Assignment with the Rest Operator to Reassign Array Elements
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challengeType: 1
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videoUrl: ''
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localeTitle: 使用与Rest运算符的Destructuring Assignment重新分配数组元素
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---
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## Description
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<section id="description">在某些涉及数组解构的情况下，我们可能希望将其余元素收集到一个单独的数组中。结果类似于<code>Array.prototype.slice()</code> ，如下所示： <blockquote> const [a，b，... arr] = [1,2,3,4,5,7]; <br> console.log（a，b）; // 1,2 <br>的console.log（ARR）; // [3,4,5,7] </blockquote>变量<code>a</code>和<code>b</code>从数组中获取第一个和第二个值。之后，由于rest操作符的存在， <code>arr</code>以数组的形式获取其余的值。 rest元素仅作为列表中的最后一个变量正常工作。在中，您不能使用rest运算符来捕获一个子数组，该子数组会遗漏原始数组的最后一个元素。 </section>
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## Instructions
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<section id="instructions">使用与rest运算符的解构赋值来执行有效的<code>Array.prototype.slice()</code>以便<code>arr</code>是原始数组<code>source</code>的子数组，省略前两个元素。 </section>
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## Tests
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<section id='tests'>
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```yml
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tests:
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- text: '<code>arr</code>应为<code>[3,4,5,6,7,8,9,10]</code>'
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testString: 'assert(arr.every((v, i) => v === i + 3) && arr.length === 8,"<code>arr</code> should be <code>[3,4,5,6,7,8,9,10]</code>");'
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- text: 应该使用解构。
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testString: 'getUserInput => assert(getUserInput("index").match(/\[\s*\w*\s*,\s*\w*\s*,\s*...\w+\s*\]/g),"Destructuring should be used.");'
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- text: 不应使用<code>Array.slice()</code> 。
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testString: 'getUserInput => assert(!getUserInput("index").match(/slice/g), "<code>Array.slice()</code> should not be used.");'
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```
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</section>
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## Challenge Seed
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<section id='challengeSeed'>
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<div id='js-seed'>
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```js
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const source = [1,2,3,4,5,6,7,8,9,10];
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function removeFirstTwo(list) {
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"use strict";
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// change code below this line
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arr = list; // change this
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// change code above this line
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return arr;
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}
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const arr = removeFirstTwo(source);
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console.log(arr); // should be [3,4,5,6,7,8,9,10]
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console.log(source); // should be [1,2,3,4,5,6,7,8,9,10];
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```
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</div>
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</section>
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## Solution
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<section id='solution'>
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```js
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// solution required
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```
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</section>
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