freeCodeCamp/curriculum/challenges/english/02-javascript-algorithms-an.../basic-algorithm-scripting/falsy-bouncer.md

64 lines
1.1 KiB
Markdown
Raw Normal View History

---
id: adf08ec01beb4f99fc7a68f2
title: Falsy Bouncer
challengeType: 5
forumTopicId: 16014
dashedName: falsy-bouncer
---
# --description--
Remove all falsy values from an array.
Falsy values in JavaScript are `false`, `null`, `0`, `""`, `undefined`, and `NaN`.
Hint: Try converting each value to a Boolean.
# --hints--
`bouncer([7, "ate", "", false, 9])` should return `[7, "ate", 9]`.
```js
assert.deepEqual(bouncer([7, 'ate', '', false, 9]), [7, 'ate', 9]);
```
`bouncer(["a", "b", "c"])` should return `["a", "b", "c"]`.
```js
assert.deepEqual(bouncer(['a', 'b', 'c']), ['a', 'b', 'c']);
```
`bouncer([false, null, 0, NaN, undefined, ""])` should return `[]`.
```js
assert.deepEqual(bouncer([false, null, 0, NaN, undefined, '']), []);
```
`bouncer([null, NaN, 1, 2, undefined])` should return `[1, 2]`.
```js
assert.deepEqual(bouncer([null, NaN, 1, 2, undefined]), [1, 2]);
```
# --seed--
## --seed-contents--
```js
function bouncer(arr) {
return arr;
}
bouncer([7, "ate", "", false, 9]);
```
# --solutions--
```js
function bouncer(arr) {
return arr.filter(e => e);
}
bouncer([7, "ate", "", false, 9]);
```