import { OnDestroy } from '@angular/core';
import { Subject } from 'rxjs';
import * as i0 from "@angular/core";
/**
 * @description
 *
 * Developers should explicitly add this service to providers; it then can be injected
 * into a constructor and used as a notifier for the `takeUntil` operator. This eliminates
 * the need for boilerplates with subscriptions, and we don't need to implement the `OnDestroy`
 * interface and teardown subscriptions there.
 *
 * This can be used as follows:
 * ```ts
 * @Component({
 *   selector: 'clr-button-group',
 *   templateUrl: 'button-group.html',
 *   providers: [ClrDestroyService],
 * })
 * export class ClrButtonGroup {
 *   constructor(public buttonGroupNewService: ButtonInGroupService, private destroy$: ClrDestroyService) {}
 *
 *   ngAfterContentInit() {
 *     this.buttonGroupNewService.changes.pipe(takeUntil(this.destroy$)).subscribe(button => this.rearrangeButton(button));
 *   }
 * }
 * ```
 */
export declare class ClrDestroyService extends Subject<void> implements OnDestroy {
    ngOnDestroy(): void;
    static ɵfac: i0.ɵɵFactoryDeclaration<ClrDestroyService, never>;
    static ɵprov: i0.ɵɵInjectableDeclaration<ClrDestroyService>;
}