* 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: Create a 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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A promise in JavaScript is exactly what it sounds like - you use it to make a promise to do something, usually asynchronously. When the task completes, you either fulfill your promise or fail to do so. `Promise` is a constructor function, so you need to use the `new` keyword to create one. It takes a function, as its argument, with two parameters - `resolve` and `reject`. These are methods used to determine the outcome of the promise. The syntax looks like this:
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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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Create a new promise called `makeServerRequest`. Pass in a function with `resolve` and `reject` parameters to the constructor.
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# --hints--
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You should assign a promise to a declared variable named `makeServerRequest`.
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```js
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assert(makeServerRequest instanceof Promise);
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```
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Your promise should receive a function with `resolve` and `reject` as parameters.
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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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