75 lines
1.6 KiB
Markdown
75 lines
1.6 KiB
Markdown
---
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id: bd7123c9c441eddfaeb5bdef
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challengeType: 1
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videoUrl: 'https://scrimba.com/c/c9Me8t4'
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forumTopicId: 301176
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title: 理解布尔值
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---
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## Description
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<section id='description'>
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另一种数据类型是<dfn>布尔</dfn>（Boolean）。<code>布尔</code>值要么是<code>true</code>要么是<code>false</code>。它非常像电路开关，<code>true</code>是 “开”，<code>false</code>是 “关”。这两种状态是互斥的。
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<strong>注意</strong><br><code>布尔值</code>是不带引号的，<code>"true"</code>和<code>"false"</code>是<code>字符串</code>而不是<code>布尔值</code>，在 JavaScript 中也没有特殊含义。
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</section>
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## Instructions
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<section id='instructions'>
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修改<code>welcomeToBooleans</code>函数，让它返回<code>true</code>而不是<code>false</code>。
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</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>welcomeToBooleans()</code>函数应该返回一个布尔值 (true/false)。
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testString: assert(typeof welcomeToBooleans() === 'boolean');
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- text: <code>welcomeToBooleans()</code>应该返回 true。
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testString: assert(welcomeToBooleans() === true);
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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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function welcomeToBooleans() {
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// Only change code below this line.
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return false; // Change this line
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// Only change code above this line.
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}
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```
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</div>
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### After Test
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<div id='js-teardown'>
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```js
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welcomeToBooleans();
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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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function welcomeToBooleans() {
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return true; // Change this line
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}
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```
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</section>
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