66 lines
2.0 KiB
Markdown
66 lines
2.0 KiB
Markdown
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---
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id: 587d7b88367417b2b2512b44
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title: Write Arrow Functions with Parameters
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challengeType: 1
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---
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## Description
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<section id='description'>
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Just like a normal function, you can pass arguments into arrow functions.
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<blockquote>// doubles input value and returns it<br>const doubler = (item) => item * 2;</blockquote>
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You can pass more than one argument into arrow functions as well.
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</section>
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## Instructions
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<section id='instructions'>
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Rewrite the <code>myConcat</code> function which appends contents of <code>arr2</code> to <code>arr1</code> so that the function uses arrow function syntax.
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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: User did replace <code>var</code> keyword.
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testString: 'getUserInput => assert(!getUserInput(''index'').match(/var/g), ''User did replace <code>var</code> keyword.'');'
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- text: <code>myConcat</code> should be a constant variable (by using <code>const</code>).
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testString: 'getUserInput => assert(getUserInput(''index'').match(/const\s+myConcat/g), ''<code>myConcat</code> should be a constant variable (by using <code>const</code>).'');'
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- text: <code>myConcat</code> should be a function
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testString: 'assert(typeof myConcat === ''function'', ''<code>myConcat</code> should be a function'');'
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- text: <code>myConcat()</code> returns the correct <code>array</code>
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testString: 'assert(() => { const a = myConcat([1], [2]); return a[0] == 1 && a[1] == 2; }, ''<code>myConcat()</code> returns the correct <code>array</code>'');'
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- text: <code>function</code> keyword was not used.
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testString: 'getUserInput => assert(!getUserInput(''index'').match(/function/g), ''<code>function</code> keyword was not used.'');'
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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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var myConcat = function(arr1, arr2) {
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"use strict";
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return arr1.concat(arr2);
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};
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// test your code
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console.log(myConcat([1, 2], [3, 4, 5]));
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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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