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fix(learn): remove white space for quick fix (#40231)

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* fix(learn): remove white space for quick fix

Co-authored-by: Nicholas Carrigan (he/him) <nhcarrigan@gmail.com>
This commit is contained in:
Shaun Hamilton
2020-11-20 08:21:21 +00:00
committed by GitHub
parent 72b8629ecc
commit bce3d5b372
1 changed files with 11 additions and 6 deletions
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17
curriculum/challenges/english/02-javascript-algorithms-and-data-structures/functional-programming/use-higher-order-functions-map-filter-or-reduce-to-solve-a-complex-problem.md
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@@ -1,49 +1,53 @@
---
id: 587d7b88367417b2b2512b45
title: Use Higher-Order Functions map, filter, or reduce to Solve a Complex Problem
title: Use Higher-Order Functions map, filter, or reduce to Solve a Complex Problem
challengeType: 1
forumTopicId: 301311
---
## Description
<section id='description'>
Now that you have worked through a few challenges using higher-order functions like <code>map()</code>, <code>filter()</code>, and <code>reduce()</code>, you now get to apply them to solve a more complex challenge.
</section>
## Instructions
<section id='instructions'>
We have defined a function named <code>squareList</code>. You need to complete the code for the <code>squareList</code> function using any combination of <code>map()</code>, <code>filter()</code>, and <code>reduce()</code> so that it returns a new array containing only the square of <em>only</em> the positive integers (decimal numbers are not integers) when an array of real numbers is passed to it. An example of an array containing only real numbers is <code>[-3, 4.8, 5, 3, -3.2]</code>.
<strong>Note:</strong> Your function should not use any kind of <code>for</code> or <code>while</code> loops or the <code>forEach()</code> function.
</section>
## Tests
<section id='tests'>
```yml
tests:
- text: <code>squareList</code> should be a <code>function</code>.
testString: assert.typeOf(squareList, 'function'), '<code>squareList</code> should be a <code>function</code>';
- text: for or while loops or forEach should not be used.
- text: <code>for</code>, <code>while</code>, and <code>forEach</code> should not be used.
testString: assert(!__helpers.removeJSComments(code).match(/for|while|forEach/g));
- text: <code>map</code>, <code>filter</code>, or <code>reduce</code> should be used.
testString: assert(__helpers.removeJSComments(code).match(/\.(map|filter|reduce)\s*\(/g));
testString: assert(__helpers.removeWhiteSpace(__helpers.removeJSComments(code)).match(/\.(map|filter|reduce)\(/g));
- text: The function should return an <code>array</code>.
testString: assert(Array.isArray(squareList([4, 5.6, -9.8, 3.14, 42, 6, 8.34, -2])));
- text: <code>squareList([4, 5.6, -9.8, 3.14, 42, 6, 8.34, -2])</code> should return <code>[16, 1764, 36]</code>.
testString: assert.deepStrictEqual(squareList([4, 5.6, -9.8, 3.14, 42, 6, 8.34, -2]), [16, 1764, 36]);
- text: <code>squareList([-3.7, -5, 3, 10, 12.5, 7, -4.5, -17, 0.3])</code> should return <code>[9, 100, 49]</code>.
testString: assert.deepStrictEqual(squareList([-3.7, -5, 3, 10, 12.5, 7, -4.5, -17, 0.3]), [9, 100, 49]);
testString: assert.deepStrictEqual(squareList([-3.7, -5, 3, 10, 12.5, 7, -4.5, -17, 0.3]), [9, 100, 49]);
```
</section>
## Challenge Seed
<section id='challengeSeed'>
<div id='js-seed'>
```js
const squareList = (arr) => {
const squareList = arr => {
// Only change code below this line
return arr;
// Only change code above this line
@@ -58,10 +62,11 @@ console.log(squaredIntegers);
</section>
## Solution
<section id='solution'>
```js
const squareList = (arr) => {
const squareList = arr => {
const positiveIntegers = arr.filter(num => {
return num >= 0 && Number.isInteger(num);
});