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30-seconds-of-code/snippets/forOwnRight.md
Isabelle Viktoria Maciohsek 27c168ce55 Bake date into snippets
2021-06-13 13:55:00 +03:00

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---
title: forOwnRight
tags: object,intermediate
firstSeen: 2018-01-18T16:45:56+02:00
lastUpdated: 2020-10-19T22:49:51+03:00
---
Iterates over all own properties of an object in reverse, running a callback for each one.
- Use `Object.keys(obj)` to get all the properties of the object, `Array.prototype.reverse()` to reverse their order.
- Use `Array.prototype.forEach()` to run the provided function for each key-value pair.
- The callback receives three arguments - the value, the key and the object.
```js
const forOwnRight = (obj, fn) =>
Object.keys(obj)
.reverse()
.forEach(key => fn(obj[key], key, obj));
```
```js
forOwnRight({ foo: 'bar', a: 1 }, v => console.log(v)); // 1, 'bar'
```