77 lines
1.5 KiB
Markdown
77 lines
1.5 KiB
Markdown
---
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id: 56533eb9ac21ba0edf2244ad
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title: Decrement a Number with JavaScript
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challengeType: 1
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videoUrl: 'https://scrimba.com/c/cM2KeS2'
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---
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## Description
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<section id='description'>
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You can easily <dfn>decrement</dfn> or decrease a variable by one with the <code>--</code> operator.
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<code>i--;</code>
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is the equivalent of
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<code>i = i - 1;</code>
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<strong>Note</strong><br>The entire line becomes <code>i--;</code>, eliminating the need for the equal sign.
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</section>
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## Instructions
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<section id='instructions'>
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Change the code to use the <code>--</code> operator on <code>myVar</code>.
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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>myVar</code> should equal <code>10</code>
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testString: assert(myVar === 10);
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- text: <code>myVar = myVar - 1;</code> should be changed
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testString: assert(/var\s*myVar\s*=\s*11;\s*\/*.*\s*([-]{2}\s*myVar|myVar\s*[-]{2});/.test(code));
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- text: Use the <code>--</code> operator on <code>myVar</code>
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testString: assert(/[-]{2}\s*myVar|myVar\s*[-]{2}/.test(code));
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- text: Do not change code above the line
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testString: assert(/var myVar = 11;/.test(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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var myVar = 11;
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// Only change code below this line
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myVar = myVar - 1;
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```
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</div>
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### After Test
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<div id='js-teardown'>
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```js
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(function(z){return 'myVar = ' + z;})(myVar);
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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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var myVar = 11;
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myVar--;
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```
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</section>
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