db369fbed1
* Removes comments in js challanges by default * fix local-scope-and-functions test regex * fix all languages * revert language changes * removed unnecessary removeJSComments from challenges * fix challanges in other languages * removed removeJSComments from all challanges
87 lines
1.5 KiB
Markdown
87 lines
1.5 KiB
Markdown
---
|
|
id: 587d7b8b367417b2b2512b50
|
|
title: 用 ES6 编写简洁的函数声明
|
|
challengeType: 1
|
|
forumTopicId: 301224
|
|
dashedName: write-concise-declarative-functions-with-es6
|
|
---
|
|
|
|
# --description--
|
|
|
|
在 ES5 中，当我们需要在对象中定义一个函数的时候，必须像这样使用 `function` 关键字：
|
|
|
|
```js
|
|
const person = {
|
|
name: "Taylor",
|
|
sayHello: function() {
|
|
return `Hello! My name is ${this.name}.`;
|
|
}
|
|
};
|
|
```
|
|
|
|
用 ES6 的语法在对象中定义函数的时候，可以删除 `function` 关键词和冒号。 请看以下例子：
|
|
|
|
```js
|
|
const person = {
|
|
name: "Taylor",
|
|
sayHello() {
|
|
return `Hello! My name is ${this.name}.`;
|
|
}
|
|
};
|
|
```
|
|
|
|
# --instructions--
|
|
|
|
使用以上这种简短的语法，重构在 `bicycle` 对象中的 `setGear` 函数。
|
|
|
|
# --hints--
|
|
|
|
不应使用传统的函数定义方法。
|
|
|
|
```js
|
|
(getUserInput) => assert(!code.match(/function/));
|
|
```
|
|
|
|
`setGear` 应是一个声明函数。
|
|
|
|
```js
|
|
assert(
|
|
typeof bicycle.setGear === 'function' && code.match(/setGear\s*\(.+\)\s*\{/)
|
|
);
|
|
```
|
|
|
|
`bicycle.setGear(48)` 应将 `gear` 的值改为 48。
|
|
|
|
```js
|
|
assert(new bicycle.setGear(48).gear === 48);
|
|
```
|
|
|
|
# --seed--
|
|
|
|
## --seed-contents--
|
|
|
|
```js
|
|
// Only change code below this line
|
|
const bicycle = {
|
|
gear: 2,
|
|
setGear: function(newGear) {
|
|
this.gear = newGear;
|
|
}
|
|
};
|
|
// Only change code above this line
|
|
bicycle.setGear(3);
|
|
console.log(bicycle.gear);
|
|
```
|
|
|
|
# --solutions--
|
|
|
|
```js
|
|
const bicycle = {
|
|
gear: 2,
|
|
setGear(newGear) {
|
|
this.gear = newGear;
|
|
}
|
|
};
|
|
bicycle.setGear(3);
|
|
```
|