---
title: "@unikvs/null"
description: "Usage of Null in @unikvs/null, a test storage that discards writes."
---

## Overview [#overview]

`@unikvs/null` Usage of Null in @unikvs/null, a test storage that discards writes.

- `name` is `Null`.
- `isOpen` is always `true`.
- No `open` or `close`.

Install with:

```package-install
npm install @unikvs/null
```

## Usage [#usage]

Null implements IStorage. Pass it to UniKvs with persist().

```ts
import { Null } from "@unikvs/null";
```

The following example confirms writes are discarded.

```ts
import { Null } from "@unikvs/null";
import * as unikvs from "unikvs";

const kvs = new unikvs.Builder<{
  greeting: unikvs.PlainValue<string>;
}>()
  .persist(new Null())
  .build();

await kvs.open();
await kvs.set("greeting", "hello");

console.log(await kvs.has("greeting")); // false

await kvs.close();
```

## Data types [#data-types]

| Operation                            | Supported data type             |
| ------------------------------------ | ------------------------------- |
| `write` / `read`                     | Arbitrary values (never stored) |
| `getWritable` / `getReadable` chunks | Arbitrary values (never stored) |

- Discards every written value.
- `read`, `delete`, and `getReadable` always throw `KeyNotFoundError`.
- `exists` always returns `false`.
- `clear` does nothing.
- `getWritable` discards all written chunks.

## Errors [#errors]

This package has no package-specific errors. Failed reads throw `KeyNotFoundError`, the shared error from `@unikvs/core`.