63 lines
		
	
	
		
			2.0 KiB
		
	
	
	
		
			Markdown
		
	
	
	
	
	
		
		
			
		
	
	
			63 lines
		
	
	
		
			2.0 KiB
		
	
	
	
		
			Markdown
		
	
	
	
	
	
|   | --- | |||
|  | id: 587d7b88367417b2b2512b44 | |||
|  | title: Write Arrow Functions with Parameters | |||
|  | challengeType: 1 | |||
|  | videoUrl: '' | |||
|  | localeTitle: 用参数写箭头函数 | |||
|  | --- | |||
|  | 
 | |||
|  | ## Description
 | |||
|  | <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> | |||
|  | 
 | |||
|  | ## Instructions
 | |||
|  | <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> | |||
|  | 
 | |||
|  | ## Tests
 | |||
|  | <section id='tests'> | |||
|  | 
 | |||
|  | ```yml | |||
|  | tests: | |||
|  |   - text: 用户确实替换了<code>var</code>关键字。 | |||
|  |     testString: 'getUserInput => assert(!getUserInput("index").match(/var/g), "User did replace <code>var</code> keyword.");' | |||
|  |   - text: <code>myConcat</code>应该是一个常量变量(使用<code>const</code> )。 | |||
|  |     testString: 'getUserInput => assert(getUserInput("index").match(/const\s+myConcat/g), "<code>myConcat</code> should be a constant variable (by using <code>const</code>).");' | |||
|  |   - text: <code>myConcat</code>应该是一个函数 | |||
|  |     testString: 'assert(typeof myConcat === "function", "<code>myConcat</code> should be a function");' | |||
|  |   - text: <code>myConcat()</code>返回正确的<code>array</code> | |||
|  |     testString: 'assert(() => { const a = myConcat([1], [2]); return a[0] == 1 && a[1] == 2; }, "<code>myConcat()</code> returns the correct <code>array</code>");' | |||
|  |   - text: <code>function</code>关键字未使用。 | |||
|  |     testString: 'getUserInput => assert(!getUserInput("index").match(/function/g), "<code>function</code> keyword was not used.");' | |||
|  | 
 | |||
|  | ``` | |||
|  | 
 | |||
|  | </section> | |||
|  | 
 | |||
|  | ## Challenge Seed
 | |||
|  | <section id='challengeSeed'> | |||
|  | 
 | |||
|  | <div id='js-seed'> | |||
|  | 
 | |||
|  | ```js | |||
|  | var myConcat = function(arr1, arr2) { | |||
|  |   "use strict"; | |||
|  |   return arr1.concat(arr2); | |||
|  | }; | |||
|  | // test your code | |||
|  | console.log(myConcat([1, 2], [3, 4, 5])); | |||
|  | 
 | |||
|  | ``` | |||
|  | 
 | |||
|  | </div> | |||
|  | 
 | |||
|  | 
 | |||
|  | 
 | |||
|  | </section> | |||
|  | 
 | |||
|  | ## Solution
 | |||
|  | <section id='solution'> | |||
|  | 
 | |||
|  | ```js | |||
|  | // solution required | |||
|  | ``` | |||
|  | </section> |