f1c9b08cf3
This includes certificates (where it does nothing), but does not include any translations.
81 lines
2.0 KiB
Markdown
81 lines
2.0 KiB
Markdown
---
|
|
id: 587d7dab367417b2b2512b6e
|
|
title: Use the every Method to Check that Every Element in an Array Meets a Criteria
|
|
challengeType: 1
|
|
isHidden: false
|
|
forumTopicId: 301312
|
|
---
|
|
|
|
## Description
|
|
<section id='description'>
|
|
The <code>every</code> method works with arrays to check if <em>every</em> element passes a particular test. It returns a Boolean value - <code>true</code> if all values meet the criteria, <code>false</code> if not.
|
|
For example, the following code would check if every element in the <code>numbers</code> array is less than 10:
|
|
|
|
```js
|
|
var numbers = [1, 5, 8, 0, 10, 11];
|
|
numbers.every(function(currentValue) {
|
|
return currentValue < 10;
|
|
});
|
|
// Returns false
|
|
```
|
|
|
|
</section>
|
|
|
|
## Instructions
|
|
<section id='instructions'>
|
|
Use the <code>every</code> method inside the <code>checkPositive</code> function to check if every element in <code>arr</code> is positive. The function should return a Boolean value.
|
|
</section>
|
|
|
|
## Tests
|
|
<section id='tests'>
|
|
|
|
```yml
|
|
tests:
|
|
- text: Your code should use the <code>every</code> method.
|
|
testString: assert(code.match(/\.every/g));
|
|
- text: <code>checkPositive([1, 2, 3, -4, 5])</code> should return <code>false</code>.
|
|
testString: assert.isFalse(checkPositive([1, 2, 3, -4, 5]));
|
|
- text: <code>checkPositive([1, 2, 3, 4, 5])</code> should return <code>true</code>.
|
|
testString: assert.isTrue(checkPositive([1, 2, 3, 4, 5]));
|
|
- text: <code>checkPositive([1, -2, 3, -4, 5])</code> should return <code>false</code>.
|
|
testString: assert.isFalse(checkPositive([1, -2, 3, -4, 5]));
|
|
|
|
```
|
|
|
|
</section>
|
|
|
|
## Challenge Seed
|
|
<section id='challengeSeed'>
|
|
|
|
<div id='js-seed'>
|
|
|
|
```js
|
|
function checkPositive(arr) {
|
|
// Only change code below this line
|
|
|
|
|
|
// Only change code above this line
|
|
}
|
|
checkPositive([1, 2, 3, -4, 5]);
|
|
```
|
|
|
|
</div>
|
|
|
|
|
|
|
|
</section>
|
|
|
|
## Solution
|
|
<section id='solution'>
|
|
|
|
```js
|
|
function checkPositive(arr) {
|
|
// Only change code below this line
|
|
return arr.every(num => num > 0);
|
|
// Only change code above this line
|
|
}
|
|
checkPositive([1, 2, 3, -4, 5]);
|
|
```
|
|
|
|
</section>
|