Lists all indices.
[:package:](https://www.npmjs.com/package/@extra-array/keys)
[:smiley_cat:](https://github.com/orgs/nodef/packages?repo_name=extra-array)
[:running:](https://npm.runkit.com/@extra-array/keys)
[:vhs:](https://asciinema.org/a/332087)
[:moon:](https://www.npmjs.com/package/@extra-array/keys.min)
[:scroll:](https://unpkg.com/@extra-array/keys/)
[:newspaper:](https://nodef.github.io/extra-array/)
[:blue_book:](https://github.com/nodef/extra-array/wiki/)

> Similar: [keys], [values], [entries].

> This is part of package [extra-array].

[extra-array]: https://www.npmjs.com/package/extra-array

<br>

```javascript
array.keys(x);
// x: an array
```

```javascript
const array = require("extra-array");

var x = [1, 2, 3];
[...array.keys(x)];
// [ 0, 1, 2 ]
```

<br>
<br>


## References

- [Array.prototype.keys: MDN web docs](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/keys)

[keys]: https://github.com/nodef/extra-array/wiki/keys
[values]: https://github.com/nodef/extra-array/wiki/values
[entries]: https://github.com/nodef/extra-array/wiki/entries