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>
55 lines
1.3 KiB
Markdown
55 lines
1.3 KiB
Markdown
---
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id: 5cdafbb0291309899753167f
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title: 创建一个 JavaScript Promise
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challengeType: 1
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forumTopicId: 301197
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dashedName: create-a-javascript-promise
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---
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# --description--
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Promise 是异步编程的一种解决方案 - 它在未来的某时会生成一个值。任务完成，分执行成功和执行失败两种情况。`Promise` 是构造器函数，需要通过 `new` 关键字来创建。构造器参数是一个函数，该函数有两个参数 - `resolve` 和 `reject`。通过它们来判断 promise 的执行结果。用法如下：
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```js
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const myPromise = new Promise((resolve, reject) => {
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});
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```
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# --instructions--
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创建一个名为 `makeServerRequest` 的 promise。给构造器函数传入 `resolve` 和 `reject` 两个参数。
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# --hints--
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应该给名为 `makeServerRequest` 的变量指定一个 promise。
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```js
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assert(makeServerRequest instanceof Promise);
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```
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promise 应该接收一个函数做为参数，该函数应该包含 `resolve` 和 `reject` 两个参数。
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```js
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assert(
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code.match(
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/Promise\(\s*(function\s*\(\s*resolve\s*,\s*reject\s*\)\s*{|\(\s*resolve\s*,\s*reject\s*\)\s*=>\s*{)[^}]*}/g
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)
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);
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```
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# --seed--
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## --seed-contents--
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```js
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```
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# --solutions--
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```js
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const makeServerRequest = new Promise((resolve, reject) => {
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});
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```
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