These changes introduce the new `@Service` decorator which is a more ergonomic alternative to `@Injectable`. The reason we're adding a new decorator is that `@Injectable` has been around since the beginning of Angular and it has a lot of baggage that adds unnecessary overhead for users that generally want to define a singleton service, available in their entire app. The key differences between `@Service` and `@Injectable` are:
1. `@Service` is `providedIn: 'root'` by default. You can opt into providing the service yourself by setting `autoProvided: false` on it.
2. `@Service` doesn't allow constructor-based injection, only the `inject` function.
3. `@Service` doesn't support the complex type signature of `@Injectable` (`useClass`, `useValue` etc.). Instead it supports a single `factory` function.
Example:
```ts
import {Service} from '@angular/core';
import {HttpClient} from '@angular/common/http';
import {AuthService} from './auth';
@Service()
export class PostService {
private readonly httpClient = inject(HttpClient);
private readonly authService = inject(AuthService);
getUserPosts() {
return this.httpClient.get('/api/posts/' + this.authService.userId);
}
}
```