88 lines
3.3 KiB
Markdown
88 lines
3.3 KiB
Markdown
---
|
|
id: 587d7dab367417b2b2512b6d
|
|
title: Apply Functional Programming to Convert Strings to URL Slugs
|
|
challengeType: 1
|
|
forumTopicId: 301227
|
|
---
|
|
|
|
## Description
|
|
<section id='description'>
|
|
The last several challenges covered a number of useful array and string methods that follow functional programming principles. We've also learned about <code>reduce</code>, which is a powerful method used to reduce problems to simpler forms. From computing averages to sorting, any array operation can be achieved by applying it. Recall that <code>map</code> and <code>filter</code> are special cases of <code>reduce</code>.
|
|
Let's combine what we've learned to solve a practical problem.
|
|
Many content management sites (CMS) have the titles of a post added to part of the URL for simple bookmarking purposes. For example, if you write a Medium post titled "Stop Using Reduce", it's likely the URL would have some form of the title string in it (".../stop-using-reduce"). You may have already noticed this on the freeCodeCamp site.
|
|
</section>
|
|
|
|
## Instructions
|
|
<section id='instructions'>
|
|
Fill in the <code>urlSlug</code> function so it converts a string <code>title</code> and returns the hyphenated version for the URL. You can use any of the methods covered in this section, and don't use <code>replace</code>. Here are the requirements:
|
|
The input is a string with spaces and title-cased words
|
|
The output is a string with the spaces between words replaced by a hyphen (<code>-</code>)
|
|
The output should be all lower-cased letters
|
|
The output should not have any spaces
|
|
</section>
|
|
|
|
## Tests
|
|
<section id='tests'>
|
|
|
|
```yml
|
|
tests:
|
|
- text: The <code>globalTitle</code> variable should not change.
|
|
testString: assert(globalTitle === "Winter Is Coming");
|
|
- text: Your code should not use the <code>replace</code> method for this challenge.
|
|
testString: assert(!code.match(/\.replace/g));
|
|
- text: <code>urlSlug("Winter Is Coming")</code> should return <code>"winter-is-coming"</code>.
|
|
testString: assert(urlSlug("Winter Is Coming") === "winter-is-coming");
|
|
- text: <code>urlSlug(" Winter Is Coming")</code> should return <code>"winter-is-coming"</code>.
|
|
testString: assert(urlSlug(" Winter Is Coming") === "winter-is-coming");
|
|
- text: <code>urlSlug("A Mind Needs Books Like A Sword Needs A Whetstone")</code> should return <code>"a-mind-needs-books-like-a-sword-needs-a-whetstone"</code>.
|
|
testString: assert(urlSlug("A Mind Needs Books Like A Sword Needs A Whetstone") === "a-mind-needs-books-like-a-sword-needs-a-whetstone");
|
|
- text: <code>urlSlug("Hold The Door")</code> should return <code>"hold-the-door"</code>.
|
|
testString: assert(urlSlug("Hold The Door") === "hold-the-door");
|
|
|
|
```
|
|
|
|
</section>
|
|
|
|
## Challenge Seed
|
|
<section id='challengeSeed'>
|
|
|
|
<div id='js-seed'>
|
|
|
|
```js
|
|
// the global variable
|
|
var globalTitle = "Winter Is Coming";
|
|
|
|
// Add your code below this line
|
|
function urlSlug(title) {
|
|
|
|
|
|
}
|
|
// Add your code above this line
|
|
|
|
var winterComing = urlSlug(globalTitle); // Should be "winter-is-coming"
|
|
```
|
|
|
|
</div>
|
|
|
|
|
|
|
|
</section>
|
|
|
|
## Solution
|
|
<section id='solution'>
|
|
|
|
```js
|
|
// the global variable
|
|
var globalTitle = "Winter Is Coming";
|
|
|
|
// Add your code below this line
|
|
function urlSlug(title) {
|
|
return title.trim().split(/\s+/).join("-").toLowerCase();
|
|
}
|
|
// Add your code above this line
|
|
|
|
var winterComing = urlSlug(globalTitle); // Should be "winter-is-coming"
|
|
```
|
|
|
|
</section>
|