Within my TS file, a declaration is present:
import { Select } from '@ngxs/store';
@Injectable()
export class someService {
@Select(someSELECTOR) varName$!: Observable<someType[]>;
elements$ = this.varName$.pipe(
map(elements => elements.map(SOMElogic),
);
}
I am curious about the varName$! part. Typically, we use $ to denote an observable, but what does the ! signify? It isn't part of the variable name since it is omitted when used in conjunction with pipe below.
Does the ! carry any specific meaning within NGXS, TypeScript, or Angular?