ee1e8abd87
* feat(tools): add seed/solution restore script * chore(curriculum): remove empty sections' markers * chore(curriculum): add seed + solution to Chinese * chore: remove old formatter * fix: update getChallenges parse translated challenges separately, without reference to the source * chore(curriculum): add dashedName to English * chore(curriculum): add dashedName to Chinese * refactor: remove unused challenge property 'name' * fix: relax dashedName requirement * fix: stray tag Remove stray `pre` tag from challenge file. Signed-off-by: nhcarrigan <nhcarrigan@gmail.com> Co-authored-by: nhcarrigan <nhcarrigan@gmail.com>
81 lines
1.5 KiB
Markdown
81 lines
1.5 KiB
Markdown
---
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id: 56533eb9ac21ba0edf2244bf
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title: 局部作用域和函数
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challengeType: 1
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videoUrl: 'https://scrimba.com/c/cd62NhM'
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forumTopicId: 18227
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dashedName: local-scope-and-functions
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---
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# --description--
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在一个函数内声明的变量，以及该函数的参数都是局部变量，意味着它们只在该函数内可见。
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这是在函数`myTest`内声明局部变量`loc`的例子：
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```js
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function myTest() {
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var loc = "foo";
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console.log(loc);
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}
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myTest(); // logs "foo"
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console.log(loc); // loc is not defined
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```
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在函数外，`loc`是未定义的。
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# --instructions--
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在函数`myFunction`内部声明一个局部变量`myVar`，并删除外部的 console.log。
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**提示：**
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如果你遇到了问题，可以先尝试刷新页面。
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# --hints--
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未找到全局的`myVar`变量。
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```js
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assert(typeof myVar === 'undefined');
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```
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需要定义局部的`myVar`变量。
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```js
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assert(/var\s+myVar/.test(code));
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```
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# --seed--
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## --seed-contents--
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```js
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function myLocalScope() {
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// Only change code below this line
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console.log('inside myLocalScope', myVar);
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}
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myLocalScope();
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// Run and check the console
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// myVar is not defined outside of myLocalScope
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console.log('outside myLocalScope', myVar);
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```
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# --solutions--
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```js
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function myLocalScope() {
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// Only change code below this line
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var myVar;
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console.log('inside myLocalScope', myVar);
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}
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myLocalScope();
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// Run and check the console
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// myVar is not defined outside of myLocalScope
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console.log('outside myLocalScope', myVar);
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```
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