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>
99 lines
2.1 KiB
Markdown
99 lines
2.1 KiB
Markdown
---
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id: 56533eb9ac21ba0edf2244ab
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title: 了解变量名区分大小写
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challengeType: 1
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videoUrl: 'https://scrimba.com/c/cd6GDcD'
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forumTopicId: 18334
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dashedName: understanding-case-sensitivity-in-variables
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---
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# --description--
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在 JavaScript 中所有的变量和函数名都是大小写敏感的。要区别对待大写字母和小写字母。
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`MYVAR`与`MyVar`和`myvar`是截然不同的变量。这有可能导致出现多个相似名字的的变量。所以强烈地建议你，为了保持代码清晰不要使用这一特性。
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<h4>最佳实践</h4>
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使用<dfn>驼峰命名法</dfn>来书写一个 Javascript 变量，在<dfn>驼峰命名法</dfn>中，变量名的第一个单词的首写字母小写，后面的单词的第一个字母大写。
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**示例：**
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```js
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var someVariable;
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var anotherVariableName;
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var thisVariableNameIsSoLong;
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```
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# --instructions--
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修改已声明的变量，让它们的命名符合<dfn>驼峰命名法</dfn>的规范。
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# --hints--
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`studlyCapVar`应该被定义并且值为`10`。
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```js
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assert(typeof studlyCapVar !== 'undefined' && studlyCapVar === 10);
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```
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`properCamelCase`应该被定义并且值为`"A String"`。
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```js
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assert(
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typeof properCamelCase !== 'undefined' && properCamelCase === 'A String'
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);
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```
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`titleCaseOver`应该被定义并且值为`9000`。
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```js
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assert(typeof titleCaseOver !== 'undefined' && titleCaseOver === 9000);
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```
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`studlyCapVar`在声明和赋值时都应该使用驼峰命名法。
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```js
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assert(code.match(/studlyCapVar/g).length === 2);
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```
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`properCamelCase` 在声明和赋值时都应该使用驼峰命名法。
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```js
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assert(code.match(/properCamelCase/g).length === 2);
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```
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`titleCaseOver` 在声明和赋值时都应该使用驼峰命名法。
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```js
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assert(code.match(/titleCaseOver/g).length === 2);
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```
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# --seed--
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## --seed-contents--
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```js
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// Variable declarations
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var StUdLyCapVaR;
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var properCamelCase;
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var TitleCaseOver;
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// Variable assignments
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STUDLYCAPVAR = 10;
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PRoperCAmelCAse = "A String";
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tITLEcASEoVER = 9000;
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```
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# --solutions--
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```js
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var studlyCapVar;
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var properCamelCase;
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var titleCaseOver;
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studlyCapVar = 10;
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properCamelCase = "A String";
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titleCaseOver = 9000;
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```
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