# oxc/no-this-in-exported-function

> Disallow `this` in exported functions

After `import { save } from "./store"`, a call to `save()` has no object in front of it, so `this` is `undefined` and `this.items` throws. With `import * as store`, `store.save()` sees the module's exports as `this`, but a bundler can turn that into a plain `save()` call, and then the same code only breaks in the bundle.

The rule checks `export function`, `export default function`, and functions listed in `export { name }`. An arrow function inside one of them uses the same `this`, so it's checked too. `export const save = function () {}` and `export default save` aren't checked.

{/* Generated by src/codegen/lint-rule-docs.ts. Do not edit this section. */}

## Configure

Off by default. To turn it on:

```toml bunfig.toml
[lint.rules]
"oxc/no-this-in-exported-function" = "error" # or "warn"
```

{/* End of the generated section. */}

## Examples

Reported:

{/* bad */}
```js
export function save(item) {
  this.items.push(item);
}
```

{/* bad */}
```js
function save(item) {
  return () => this.items.push(item);
}

export { save };
```

Not reported:

{/* good */}
```js
const items = [];

export function save(item) {
  items.push(item);
}
```

Pass the object as an argument if the function works on more than one:

{/* good */}
```js
export function save(store, item) {
  store.items.push(item);
}
```

A regular function or a class inside the exported function has its own `this`:

{/* good */}
```js
export function createStore() {
  return {
    items: [],
    save(item) {
      this.items.push(item);
    },
  };
}
```

## When not to use it

A function you export so it can be attached to an object or called with `.call()` uses `this` on purpose. The rule reports it even if it declares a TypeScript `this` parameter.