23 lines
493 B
Markdown
23 lines
493 B
Markdown
---
|
|
title: Logical complement
|
|
type: snippet
|
|
tags: [function,logic]
|
|
cover: flower-portrait-10
|
|
dateModified: 2020-09-15T16:28:04+03:00
|
|
---
|
|
|
|
Returns a function that is the logical complement of the given function, `fn`.
|
|
|
|
- Use the logical not (`!`) operator on the result of calling `fn` with any supplied `args`.
|
|
|
|
```js
|
|
const complement = fn => (...args) => !fn(...args);
|
|
```
|
|
|
|
```js
|
|
const isEven = num => num % 2 === 0;
|
|
const isOdd = complement(isEven);
|
|
isOdd(2); // false
|
|
isOdd(3); // true
|
|
```
|