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Merge pull request #1165 from dym-sh/patch-1

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use `instanceof` to determine if arg is an array
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Angelos Chalaris
2020-07-08 09:19:41 +03:00
committed by GitHub
parent 1a1e78007a f185a793a3
commit cf18160ec1
1 changed files with 2 additions and 2 deletions
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snippets/last.md
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@ -5,10 +5,10 @@ tags: array,beginner
Returns the last element in an array.
Check if `arr` is truthy and has a `length` property, use `arr.length - 1` to compute the index of the last element of the given array and return it, otherwise return `undefined`.
Check if `arr` is an instance of an `Array`, use `arr.length - 1` to compute the index of the last element of the given array and return it, otherwise return `undefined`.
```js
const last = arr => (arr && arr.length ? arr[arr.length - 1] : undefined);
const last = arr => (arr instanceof Array ? arr[arr.length - 1] : undefined);
```
```js