95 lines
2.6 KiB
Markdown
95 lines
2.6 KiB
Markdown
---
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id: 587d7b89367417b2b2512b49
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title: Use Destructuring Assignment to Assign Variables from Objects
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challengeType: 1
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forumTopicId: 301215
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---
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## Description
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<section id='description'>
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Destructuring allows you to assign a new variable name when extracting values. You can do this by putting the new name after a colon when assigning the value.
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Using the same object from the last example:
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```js
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const user = { name: 'John Doe', age: 34 };
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```
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Here's how you can give new variable names in the assignment:
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```js
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const { name: userName, age: userAge } = user;
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// userName = 'John Doe', userAge = 34
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```
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You may read it as "get the value of <code>user.name</code> and assign it to a new variable named <code>userName</code>" and so on.
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</section>
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## Instructions
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<section id='instructions'>
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Replace the two assignments with an equivalent destructuring assignment. It should still assign the variables <code>highToday</code> and <code>highTomorrow</code> the values of <code>today</code> and <code>tomorrow</code> from the <code>HIGH_TEMPERATURES</code> object.
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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: You should remove the ES5 assignment syntax.
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testString: assert(!code.match(/highToday = HIGH_TEMPERATURES\.today/g) && !code.match(/highTomorrow = HIGH_TEMPERATURES\.tomorrow/g))
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- text: You should use destructuring to create the <code>highToday</code> variable.
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testString: assert(code.match(/(var|const|let)\s*{\s*(today:\s*highToday[^}]*|[^,]*,\s*today\s*:\s*highToday\s*)}\s*=\s*HIGH_TEMPERATURES(;|\s+|\/\/)/g));
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- text: You should use destructuring to create the <code>highTomorrow</code> variable.
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testString: assert(code.match(/(var|const|let)\s*{\s*(tomorrow:\s*highTomorrow[^}]*|[^,]*,\s*tomorrow\s*:\s*highTomorrow\s*)}\s*=\s*HIGH_TEMPERATURES(;|\s+|\/\/)/g));
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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 HIGH_TEMPERATURES = {
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yesterday: 75,
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today: 77,
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tomorrow: 80
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};
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// change code below this line
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const highToday = HIGH_TEMPERATURES.today;
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const highTomorrow = HIGH_TEMPERATURES.tomorrow;
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// change code above this line
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console.log(yesterday) // should be not defined
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console.log(highToday); // should be 77
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console.log(highTomorrow); // should be 80
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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 HIGH_TEMPERATURES = {
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yesterday: 75,
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today: 77,
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tomorrow: 80
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};
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// change code below this line
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const { today: highToday, tomorrow: highTomorrow } = HIGH_TEMPERATURES;
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// change code above this line
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console.log(highToday); // should be 77
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console.log(highTomorrow); // should be 80
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```
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</section>
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