56 lines
		
	
	
		
			1.3 KiB
		
	
	
	
		
			Markdown
		
	
	
	
	
	
			
		
		
	
	
			56 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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| 
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| # --description--
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| 
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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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| 
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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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| ```
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| 
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| # --instructions--
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| 
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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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| 
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| # --hints--
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| 
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| You should assign a promise to a declared variable named `makeServerRequest`.
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| 
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| ```js
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| assert(makeServerRequest instanceof Promise);
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| ```
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| 
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| Your promise should receive a function with `resolve` and `reject` as parameters.
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| 
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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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| 
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| # --seed--
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| 
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| ## --seed-contents--
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| 
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| ```js
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| 
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| ```
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| 
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| # --solutions--
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| 
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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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| ```
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