> For the complete documentation index, see [llms.txt](https://voici.larswaechter.dev/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://voici.larswaechter.dev/examples/fill-empty.md).

# Fill Empty

Using the `fillEmpty` option you can provide functions for each row that replace empty values.

```javascript
import { Table } from 'voici.js'

const data = [
  { firstname: 'Homer', lastname: 'Simpson', age: 39 },
  { firstname: 'Marge', lastname: 'Simpson', age: 36 },
  { firstname: 'Bart', lastname: '', age: 10 },
  { firstname: 'Lisa', lastname: 'Simpson', age: 8 },
  { firstname: 'Maggie', lastname: '', age: 1 }
];

const config = {
  body: {
    fillEmpty: {
      lastname: () => 'Simpson'
    }
  }
};

const table = new Table(data, config);
table.printPlain();
```

Output:

```
 firstname    lastname    age  
===============================
  Homer        Simpson     39  
  Marge        Simpson     36  
  Bart         Simpson     10  
  Lisa         Simpson     8   
  Maggie       Simpson     1   
```

{% hint style="info" %}
Columns not listed in `order` appear in their original order.
{% endhint %}


---

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