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---
id: 587d7b88367417b2b2512b46
title: Set Default Parameters for Your Functions
challengeType: 1
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forumTopicId: 301209
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---
## Description
<section id='description'>
In order to help us create more flexible functions, ES6 introduces <dfn>default parameters</dfn> for functions.
Check out this code:
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```js
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const greeting = (name = "Anonymous") => "Hello " + name;
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console.log(greeting("John")); // Hello John
console.log(greeting()); // Hello Anonymous
```
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The default parameter kicks in when the argument is not specified (it is undefined). As you can see in the example above, the parameter <code>name</code> will receive its default value <code>"Anonymous"</code> when you do not provide a value for the parameter. You can add default values for as many parameters as you want.
</section>
## Instructions
<section id='instructions'>
Modify the function <code>increment</code> by adding default parameters so that it will add 1 to <code>number</code> if <code>value</code> is not specified.
</section>
## Tests
<section id='tests'>
```yml
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tests:
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- text: The result of <code>increment(5, 2)</code> should be <code>7</code>.
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testString: assert(increment(5, 2) === 7);
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- text: The result of <code>increment(5)</code> should be <code>6</code>.
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testString: assert(increment(5) === 6);
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- text: A default parameter value of <code>1</code> should be used for <code>value</code>.
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testString: assert(code.match(/value\s*=\s*1/g));
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```
</section>
## Challenge Seed
<section id='challengeSeed'>
<div id='js-seed'>
```js
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// Only change code below this line
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const increment = (number, value) => number + value;
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// Only change code above this line
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```
</div>
</section>
## Solution
<section id='solution'>
```js
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const increment = (number, value = 1) => number + value;
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```
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</section>