Type Safety with ES2022's Array.prototype.at
Ben Asher
Engineering Leadership
1 minute read
ES2022 introduces Array.prototype.at
and we've come to love using it. Array.prototype.at
can replace using the standard index operator []
:
1const arr: number[] = [];
2
3arr[0].toString();
4
5// Same as above!
6arr.at(0).toString();
In the example above, even though index 0 may not have anything there, Typescript is happy to allow us to to call toString()
. With .at()
, we get a compiler error:

Array.prototype.at
is not officially supported in all versions of Node. Check node.green to see if you can use it!