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

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---
title: dropRightWhile
tags: array,intermediate
firstSeen: 2018-01-26T12:23:18+02:00
lastUpdated: 2020-10-19T18:51:03+03:00
---
Removes elements from the end of an array until the passed function returns `true`.
Returns the remaining elements in the array.
- Loop through the array, using `Array.prototype.slice()` to drop the last element of the array until the value returned from `func` is `true`.
- Return the remaining elements.
```js
const dropRightWhile = (arr, func) => {
let rightIndex = arr.length;
while (rightIndex-- && !func(arr[rightIndex]));
return arr.slice(0, rightIndex + 1);
};
```
```js
dropRightWhile([1, 2, 3, 4], n => n < 3); // [1, 2]
```