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>
79 lines
1.3 KiB
Markdown
79 lines
1.3 KiB
Markdown
---
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id: 56533eb9ac21ba0edf2244c0
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title: 函数中的全局作用域和局部作用域
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challengeType: 1
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videoUrl: 'https://scrimba.com/c/c2QwKH2'
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forumTopicId: 18194
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dashedName: global-vs--local-scope-in-functions
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---
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# --description--
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一个程序中有可能具有相同名称的<dfn>局部</dfn>变量 和<dfn>全局</dfn>变量。在这种情况下，`局部`变量将会优先于`全局`变量。
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下面为例：
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```js
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var someVar = "Hat";
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function myFun() {
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var someVar = "Head";
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return someVar;
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}
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```
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函数`myFun`将会返回`"Head"`，因为`局部变量`优先级更高。
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# --instructions--
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给`myOutfit`添加一个局部变量来覆盖`outerWear`的值为`"sweater"`。
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# --hints--
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不要修改全局变量`outerWear`的值。
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```js
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assert(outerWear === 'T-Shirt');
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```
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`myOutfit`应该返回`"sweater"`。
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```js
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assert(myOutfit() === 'sweater');
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```
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不要修改`return`语句。
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```js
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assert(/return outerWear/.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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// Setup
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var outerWear = "T-Shirt";
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function myOutfit() {
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// Only change code below this line
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// Only change code above this line
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return outerWear;
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}
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myOutfit();
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```
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# --solutions--
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```js
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var outerWear = "T-Shirt";
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function myOutfit() {
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var outerWear = "sweater";
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return outerWear;
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}
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```
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