101 lines
2.3 KiB
Markdown
101 lines
2.3 KiB
Markdown
---
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id: 587d7b8a367417b2b2512b4d
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title: Use Destructuring Assignment to Pass an Object as a Function's Parameters
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challengeType: 1
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forumTopicId: 301217
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---
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## Description
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<section id='description'>
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In some cases, you can destructure the object in a function argument itself.
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Consider the code below:
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```js
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const profileUpdate = (profileData) => {
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const { name, age, nationality, location } = profileData;
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// do something with these variables
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}
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```
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This effectively destructures the object sent into the function. This can also be done in-place:
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```js
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const profileUpdate = ({ name, age, nationality, location }) => {
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/* do something with these fields */
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}
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```
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This removes some extra lines and makes our code look neat.
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This has the added benefit of not having to manipulate an entire object in a function — only the fields that are needed are copied inside the function.
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</section>
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## Instructions
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<section id='instructions'>
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Use destructuring assignment within the argument to the function <code>half</code> to send only <code>max</code> and <code>min</code> inside the function.
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</section>
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## Tests
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<section id='tests'>
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```yml
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tests:
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- text: <code>stats</code> should be an <code>object</code>.
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testString: assert(typeof stats === 'object');
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- text: <code>half(stats)</code> should be <code>28.015</code>
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testString: assert(half(stats) === 28.015);
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- text: Destructuring should be used.
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testString: assert(code.replace(/\s/g, '').match(/half=\({\w+,\w+}\)/));
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- text: Destructured parameter should be used.
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testString: assert(!code.match(/stats\.max|stats\.min/));
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```
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</section>
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## Challenge Seed
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<section id='challengeSeed'>
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<div id='js-seed'>
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```js
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const stats = {
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max: 56.78,
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standard_deviation: 4.34,
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median: 34.54,
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mode: 23.87,
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min: -0.75,
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average: 35.85
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};
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// change code below this line
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const half = (stats) => (stats.max + stats.min) / 2.0; // use function argument destructuring
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// change code above this line
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console.log(stats); // should be object
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console.log(half(stats)); // should be 28.015
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```
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</div>
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</section>
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## Solution
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<section id='solution'>
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```js
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const stats = {
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max: 56.78,
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standard_deviation: 4.34,
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median: 34.54,
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mode: 23.87,
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min: -0.75,
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average: 35.85
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};
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const half = ( {max, min} ) => (max + min) / 2.0;
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```
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</section>
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