73 lines
2.1 KiB
Markdown
73 lines
2.1 KiB
Markdown
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---
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id: adf08ec01beb4f99fc7a68f2
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title: Falsy Bouncer
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isRequired: true
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challengeType: 5
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---
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## Description
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<section id='description'>
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Remove all falsy values from an array.
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Falsy values in JavaScript are <code>false</code>, <code>null</code>, <code>0</code>, <code>""</code>, <code>undefined</code>, and <code>NaN</code>.
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Hint: Try converting each value to a Boolean.
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Remember to use <a href="http://forum.freecodecamp.org/t/how-to-get-help-when-you-are-stuck/19514" target="_blank">Read-Search-Ask</a> if you get stuck. Write your own code.
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</section>
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## Instructions
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<section id='instructions'>
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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>bouncer([7, "ate", "", false, 9])</code> should return <code>[7, "ate", 9]</code>.'
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testString: 'assert.deepEqual(bouncer([7, "ate", "", false, 9]), [7, "ate", 9], ''<code>bouncer([7, "ate", "", false, 9])</code> should return <code>[7, "ate", 9]</code>.'');'
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- text: '<code>bouncer(["a", "b", "c"])</code> should return <code>["a", "b", "c"]</code>.'
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testString: 'assert.deepEqual(bouncer(["a", "b", "c"]), ["a", "b", "c"], ''<code>bouncer(["a", "b", "c"])</code> should return <code>["a", "b", "c"]</code>.'');'
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- text: '<code>bouncer([false, null, 0, NaN, undefined, ""])</code> should return <code>[]</code>.'
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testString: 'assert.deepEqual(bouncer([false, null, 0, NaN, undefined, ""]), [], ''<code>bouncer([false, null, 0, NaN, undefined, ""])</code> should return <code>[]</code>.'');'
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- text: '<code>bouncer([1, null, NaN, 2, undefined])</code> should return <code>[1, 2]</code>.'
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testString: 'assert.deepEqual(bouncer([1, null, NaN, 2, undefined]), [1, 2], ''<code>bouncer([1, null, NaN, 2, undefined])</code> should return <code>[1, 2]</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 bouncer(arr) {
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// Don't show a false ID to this bouncer.
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return arr;
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}
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bouncer([7, "ate", "", false, 9]);
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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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function bouncer(arr) {
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return arr.filter(e => e);
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}
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bouncer([7, "ate", "", false, 9]);
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```
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</section>
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