# Detectors

**Kind:** Type

**Source:** [`src/middleware/language/language.ts`](https://github.com/honojs/hono/blob/main/src/middleware/language/language.ts#L197)

**Part of:** [Middleware](subsystem-src-middleware)

Type-safe detector map

`Detectors` defines the type-safe map of language detector entries used by the language middleware. It keeps detector registration aligned with the detector contract expected by the middleware.

## Definition

```ts
Record<keyof typeof detectors, DetectorFunction>
```

## Diagram

```mermaid
graph LR
  Middleware[Language middleware] --> Detectors[Detectors map]
  Detectors --> Detector[Detector entry]
  Detector --> Result[Detected language result]
```

## Usage

```ts
import type { Detectors } from './middleware/language/language';

const detectors: Detectors = {
  // Add detector entries that match the detector contract.
};

export function getDetectors(): Detectors {
  return detectors;
}
```

## AI Coding Instructions

- Keep detector map entries compatible with the detector type defined in `language.ts`.
- Import `Detectors` with `import type` when it is only used for type checking.
- Add new detector registrations through the typed map instead of bypassing type checks with casts.
- Update middleware configuration when changing the detector map or detector registration flow.