64 lines
		
	
	
		
			1.9 KiB
		
	
	
	
		
			Markdown
		
	
	
	
	
	
			
		
		
	
	
			64 lines
		
	
	
		
			1.9 KiB
		
	
	
	
		
			Markdown
		
	
	
	
	
	
| ---
 | ||
| id: 587d7b8b367417b2b2512b50
 | ||
| title: Write Concise Declarative Functions with ES6
 | ||
| challengeType: 1
 | ||
| videoUrl: ''
 | ||
| localeTitle: 用ES6编写简明的声明函数
 | ||
| ---
 | ||
| 
 | ||
| ## Description
 | ||
| <section id="description">在ES5中定义对象内的函数时,我们必须使用关键字<code>function</code> ,如下所示: <blockquote> const person = { <br>名称:“泰勒”, <br> sayHello:function(){ <br>回来`你好!我的名字是$ {this.name} .`; <br> } <br> }; </blockquote>使用ES6,您可以在定义对象中的函数时完全删除<code>function</code>关键字和冒号。以下是此语法的示例: <blockquote> const person = { <br>名称:“泰勒”, <br>问好() { <br>回来`你好!我的名字是$ {this.name} .`; <br> } <br> }; </blockquote></section>
 | ||
| 
 | ||
| ## Instructions
 | ||
| <section id="instructions">重构对象<code>bicycle</code>内的函数<code>setGear</code>以使用上述简写语法。 </section>
 | ||
| 
 | ||
| ## Tests
 | ||
| <section id='tests'>
 | ||
| 
 | ||
| ```yml
 | ||
| tests:
 | ||
|   - text: 未使用传统函数表达式。
 | ||
|     testString: 'assert(!getUserInput("index").match(/function/),"Traditional <code>function</code> expression was not used.");'
 | ||
|   - text: <code>setGear</code>是一个声明函数。
 | ||
|     testString: 'assert(typeof bicycle.setGear === "function" && getUserInput("index").match(/setGear\s*\(.+\)\s*\{/), "<code>setGear</code> is a declarative function.");'
 | ||
|   - text: ''
 | ||
|     testString: 'assert((new bicycle.setGear(48)).gear === 48, "<code>bicycle.setGear(48)</code> changes the <code>gear</code> value to 48.");'
 | ||
| 
 | ||
| ```
 | ||
| 
 | ||
| </section>
 | ||
| 
 | ||
| ## Challenge Seed
 | ||
| <section id='challengeSeed'>
 | ||
| 
 | ||
| <div id='js-seed'>
 | ||
| 
 | ||
| ```js
 | ||
| // change code below this line
 | ||
| const bicycle = {
 | ||
|   gear: 2,
 | ||
|   setGear: function(newGear) {
 | ||
|     "use strict";
 | ||
|     this.gear = newGear;
 | ||
|   }
 | ||
| };
 | ||
| // change code above this line
 | ||
| bicycle.setGear(3);
 | ||
| console.log(bicycle.gear);
 | ||
| 
 | ||
| ```
 | ||
| 
 | ||
| </div>
 | ||
| 
 | ||
| 
 | ||
| 
 | ||
| </section>
 | ||
| 
 | ||
| ## Solution
 | ||
| <section id='solution'>
 | ||
| 
 | ||
| ```js
 | ||
| // solution required
 | ||
| ```
 | ||
| </section>
 |