---
title: orderWith
tags: array,object,intermediate
---

Sorts an array of objects, ordered by a property, based on the array of orders provided.

- Use `Array.prototype.reduce()` to create an object from the `order` array with the values as keys and their original index as the value.
- Use `Array.prototype.sort()` to sort the given array, skipping elements for which `prop` is empty or not in the `order` array.

```js
const orderWith = (arr, prop, order) => {
  const orderValues = order.reduce((acc, v, i) => {
    acc[v] = i;
    return acc;
  }, {});
  return [...arr].sort((a, b) => {
    if (orderValues[a[prop]] === undefined) return 1;
    if (orderValues[b[prop]] === undefined) return -1;
    return orderValues[a[prop]] - orderValues[b[prop]];
  });
};
```

```js
const users = [
  { name: 'fred', language: 'Javascript' },
  { name: 'barney', language: 'TypeScript' },
  { name: 'frannie', language: 'Javascript' },
  { name: 'anna', language: 'Java' },
  { name: 'jimmy' },
  { name: 'nicky', language: 'Python' },
];
orderWith(users, 'language', ['Javascript', 'TypeScript', 'Java']);
/* 
[
  { name: 'fred', language: 'Javascript' },
  { name: 'frannie', language: 'Javascript' },
  { name: 'barney', language: 'TypeScript' },
  { name: 'anna', language: 'Java' },
  { name: 'jimmy' },
  { name: 'nicky', language: 'Python' }
]
*/
```