> For AI agents: the complete documentation index is available at https://rslint.rs/llms.txt, the full documentation bundle is available at https://rslint.rs/llms-full.txt.

# no-null

[Added in v0.9.1](https://github.com/web-infra-dev/rslint/releases/tag/v0.9.1)
## Configuration

| Preset                              | Configured Value |
| ----------------------------------- | ---------------- |
| ✅ unicornPlugin.configs.recommended | `"error"`        |


```ts title=rslint.config.ts
import { defineConfig, unicornPlugin } from '@rslint/core';

export default defineConfig([
  unicornPlugin.configs.recommended,
  {
    rules: {
      'unicorn/no-null': 'error',
    },
  },
]);
```

## Rule Details

Disallow the `null` literal and encourage using `undefined` as the single value
for missing data.

Examples of **incorrect** code for this rule:

```javascript
let value = null;

if (value == null) {}
```

Examples of **correct** code for this rule:

```javascript
let value;

if (value == undefined) {}

const dictionary = Object.create(null);
```

Strict equality comparisons are ignored by default:

```javascript
if (value === null) {}
```

## Options

This rule accepts an object with two boolean options:

- `checkArguments` (default: `true`) checks `null` when it is a direct function
  call or constructor argument. Set it to `false` when APIs require `null`
  arguments.
- `checkStrictEquality` (default: `false`) checks strict equality and inequality
  comparisons against `null`.

The rule follows Unicorn's built-in exceptions for `Object.create(null)`,
`useRef(null)`, `React.useRef(null)`, and `null` as the second argument of a
two-argument `insertBefore` call.

## Original Documentation

- [eslint-plugin-unicorn: no-null](https://github.com/sindresorhus/eslint-plugin-unicorn/blob/v74.0.0/docs/rules/no-null.md)
- [Source code](https://github.com/sindresorhus/eslint-plugin-unicorn/blob/v74.0.0/rules/no-null.js)