72 lines
1.3 KiB
Markdown
72 lines
1.3 KiB
Markdown
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---
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id: 598f48a36c8c40764b4e52b3
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title: Prevent Object Mutation
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challengeType: 1
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videoUrl: ''
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localeTitle: ''
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---
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## Description
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undefined
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## Instructions
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undefined
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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: ''
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testString: 'getUserInput => assert(getUserInput("index").match(/const/g), "Do not replace <code>const</code> keyword.");'
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- text: ''
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testString: 'getUserInput => assert(getUserInput("index").match(/const\s+MATH_CONSTANTS/g), "<code>MATH_CONSTANTS</code> should be a constant variable (by using <code>const</code>).");'
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- text: ''
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testString: 'getUserInput => assert(getUserInput("index").match(/const\s+MATH_CONSTANTS\s+=\s+{\s+PI:\s+3.14\s+};/g), "Do not change original <code>MATH_CONSTANTS</code>.");'
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- text: ''
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testString: 'assert(PI === 3.14, "<code>PI</code> equals <code>3.14</code>.");'
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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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function freezeObj() {
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"use strict";
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const MATH_CONSTANTS = {
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PI: 3.14
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};
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// change code below this line
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// change code above this line
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try {
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MATH_CONSTANTS.PI = 99;
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} catch( ex ) {
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console.log(ex);
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}
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return MATH_CONSTANTS.PI;
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}
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const PI = freezeObj();
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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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// solution required
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```
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</section>
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