import { OnDestroy } from '@angular/core';
import { Observable } from 'rxjs';
import * as i0 from "@angular/core";
export declare class DestroyableDirective implements OnDestroy {
    readonly destroyed$: Observable<void>;
    private readonly destroyed$$;
    constructor();
    ngOnDestroy(): void;
    static ɵfac: i0.ɵɵFactoryDeclaration<DestroyableDirective, never>;
    static ɵdir: i0.ɵɵDirectiveDeclaration<DestroyableDirective, "[inViewportDestroyable]", never, {}, {}, never, never, true, never>;
}