# Decorators and Advanced Features — Babel & SWC

Source: https://www.geekswithgeeks.com/en/babel-swc/bs-decorator-transform

> Transform decorators, class properties, and experimental JavaScript features.

## Decorators: metadata and class enhancement

Decorators (like `@Component`) are experimental. Babel and SWC need plugins to transform them into metadata or function calls.

## TypeScript decorators to function calls

`@Component` becomes a function call that wraps or modifies the class. Requires `@babel/plugin-proposal-decorators`.

```typescript
// TypeScript + Decorators
@Component({ selector: 'app' })
class AppComponent {}

// Transformed by Babel plugin
var AppComponent = __decorate([
  Component({ selector: 'app' })
], AppComponent);
```

## Use plugin options for decorator version

Decorators have multiple proposals (legacy vs new). Specify `version: '2023-05'` or similar in plugin config to control which standard Babel follows.