import { Observable } from 'rxjs';
import * as i0 from "@angular/core";
export declare class StateService {
    private sources;
    constructor();
    set(key: string, value: any, storage?: 'NONE' | 'LOCAL' | 'SESSION'): void;
    get(key: string): any;
    clear(): void;
    watch(key: string): Observable<any>;
    private getSource;
    static ɵfac: i0.ɵɵFactoryDeclaration<StateService, never>;
    static ɵprov: i0.ɵɵInjectableDeclaration<StateService>;
}