21 lines
661 B
Markdown
21 lines
661 B
Markdown
---
|
|
title: omitBy
|
|
tags: object,intermediate
|
|
---
|
|
|
|
Creates an object composed of the properties the given function returns falsy for. The function is invoked with two arguments: (value, key).
|
|
|
|
- Use `Object.keys(obj)` and `Array.prototype.filter()`to remove the keys for which `fn` returns a truthy value.
|
|
- Use `Array.prototype.reduce()` to convert the filtered keys back to an object with the corresponding key-value pairs.
|
|
|
|
```js
|
|
const omitBy = (obj, fn) =>
|
|
Object.keys(obj)
|
|
.filter(k => !fn(obj[k], k))
|
|
.reduce((acc, key) => ((acc[key] = obj[key]), acc), {});
|
|
```
|
|
|
|
```js
|
|
omitBy({ a: 1, b: '2', c: 3 }, x => typeof x === 'number'); // { b: '2' }
|
|
```
|