bfa5c26288
* Use dfn tags
* remove misused <dfn> tags
* Revert "remove misused <dfn> tags"
This reverts commit b24968a968.
* Update curriculum/challenges/english/01-responsive-web-design/basic-html-and-html5/fill-in-the-blank-with-placeholder-text.english.md
Co-Authored-By: Randell Dawson <5313213+RandellDawson@users.noreply.github.com>
* Make "array" lowercase
Co-Authored-By: Randell Dawson <5313213+RandellDawson@users.noreply.github.com>
* Fix dfn usage
* Address last dfn tags
80 lines
2.1 KiB
Markdown
80 lines
2.1 KiB
Markdown
---
|
|
id: 587d7da9367417b2b2512b66
|
|
title: Combine Two Arrays Using the concat Method
|
|
challengeType: 1
|
|
forumTopicId: 301229
|
|
---
|
|
|
|
## Description
|
|
<section id='description'>
|
|
<dfn>Concatenation</dfn> means to join items end to end. JavaScript offers the <code>concat</code> method for both strings and arrays that work in the same way. For arrays, the method is called on one, then another array is provided as the argument to <code>concat</code>, which is added to the end of the first array. It returns a new array and does not mutate either of the original arrays. Here's an example:
|
|
|
|
```js
|
|
[1, 2, 3].concat([4, 5, 6]);
|
|
// Returns a new array [1, 2, 3, 4, 5, 6]
|
|
```
|
|
|
|
</section>
|
|
|
|
## Instructions
|
|
<section id='instructions'>
|
|
Use the <code>concat</code> method in the <code>nonMutatingConcat</code> function to concatenate <code>attach</code> to the end of <code>original</code>. The function should return the concatenated array.
|
|
</section>
|
|
|
|
## Tests
|
|
<section id='tests'>
|
|
|
|
```yml
|
|
tests:
|
|
- text: Your code should use the <code>concat</code> method.
|
|
testString: assert(code.match(/\.concat/g));
|
|
- text: The <code>first</code> array should not change.
|
|
testString: assert(JSON.stringify(first) === JSON.stringify([1, 2, 3]));
|
|
- text: The <code>second</code> array should not change.
|
|
testString: assert(JSON.stringify(second) === JSON.stringify([4, 5]));
|
|
- text: <code>nonMutatingConcat([1, 2, 3], [4, 5])</code> should return <code>[1, 2, 3, 4, 5]</code>.
|
|
testString: assert(JSON.stringify(nonMutatingConcat([1, 2, 3], [4, 5])) === JSON.stringify([1, 2, 3, 4, 5]));
|
|
|
|
```
|
|
|
|
</section>
|
|
|
|
## Challenge Seed
|
|
<section id='challengeSeed'>
|
|
|
|
<div id='js-seed'>
|
|
|
|
```js
|
|
function nonMutatingConcat(original, attach) {
|
|
// Add your code below this line
|
|
|
|
|
|
// Add your code above this line
|
|
}
|
|
var first = [1, 2, 3];
|
|
var second = [4, 5];
|
|
nonMutatingConcat(first, second);
|
|
```
|
|
|
|
</div>
|
|
|
|
|
|
|
|
</section>
|
|
|
|
## Solution
|
|
<section id='solution'>
|
|
|
|
```js
|
|
function nonMutatingConcat(original, attach) {
|
|
// Add your code below this line
|
|
return original.concat(attach);
|
|
// Add your code above this line
|
|
}
|
|
var first = [1, 2, 3];
|
|
var second = [4, 5];
|
|
nonMutatingConcat(first, second);
|
|
```
|
|
|
|
</section>
|