import { Observer } from '../observer.js';
export type StorageType = 'localStorage' | 'sessionStorage';
export declare const getSessionStorageEntry: <T extends string>(key: string) => PersistentStorageEntry<T>;
export declare const getSessionStorageValue: (key: string) => string | null;
export declare const getLocalStorageEntry: <T extends string>(key: string) => PersistentStorageEntry<T>;
export declare const getLocalStorageValue: (key: string) => string | null;
export declare class PersistentStorageEntry<V extends string = string> extends Observer<V | null> {
    #private;
    constructor(storage: Storage | null, key: string);
    get storage(): Storage | null;
    get key(): string;
    get(): V | null;
    set(value: V): boolean;
    delete(): void;
    forceSync(): boolean;
}