63 lines
		
	
	
		
			2.0 KiB
		
	
	
	
		
			Markdown
		
	
	
	
	
	
		
		
			
		
	
	
			63 lines
		
	
	
		
			2.0 KiB
		
	
	
	
		
			Markdown
		
	
	
	
	
	
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								id: 587d7b88367417b2b2512b44
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								title: Write Arrow Functions with Parameters
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								challengeType: 1
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								videoUrl: ''
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								localeTitle: 用参数写箭头函数
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								---
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								## Description
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								<section id="description">就像普通函数一样,您可以将参数传递给箭头函数。 <blockquote> //将输入值加倍并返回<br> const doubler =(item)=> item * 2; </blockquote>您也可以将多个参数传递给箭头函数。 </section>
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								## Instructions
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								<section id="instructions">重写<code>myConcat</code>函数,该函数将<code>arr2</code>内容追加到<code>arr1</code>以便该函数使用箭头函数语法。 </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: 用户确实替换了<code>var</code>关键字。
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								    testString: 'getUserInput => assert(!getUserInput("index").match(/var/g), "User did replace <code>var</code> keyword.");'
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								  - text: <code>myConcat</code>应该是一个常量变量(使用<code>const</code> )。
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								    testString: 'getUserInput => assert(getUserInput("index").match(/const\s+myConcat/g), "<code>myConcat</code> should be a constant variable (by using <code>const</code>).");'
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								  - text: <code>myConcat</code>应该是一个函数
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								    testString: 'assert(typeof myConcat === "function", "<code>myConcat</code> should be a function");'
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								  - text: <code>myConcat()</code>返回正确的<code>array</code>
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								    testString: 'assert(() => { const a = myConcat([1], [2]); return a[0] == 1 && a[1] == 2; }, "<code>myConcat()</code> returns the correct <code>array</code>");'
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								  - text: <code>function</code>关键字未使用。
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								    testString: 'getUserInput => assert(!getUserInput("index").match(/function/g), "<code>function</code> keyword was not 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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								var myConcat = function(arr1, arr2) {
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								  "use strict";
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								  return arr1.concat(arr2);
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								};
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								// test your code
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								console.log(myConcat([1, 2], [3, 4, 5]));
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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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