interface AnyStorage {
    setItem: (key: string, value: string) => Promise<void> | void;
    getItem: (key: string) => Promise<string | null> | string | null;
    removeItem: (key: string) => Promise<void> | void;
}
export interface KeeperOption {
    storage: AnyStorage;
    rootKey?: string;
}
export declare function configureKeeper(option: KeeperOption): void;
export declare function getItem(key: string): Promise<any>;
export declare function setItem(key: string, value: string): Promise<void>;
export declare function removeItem(key: string): Promise<void>;
export declare function removeRoot(): Promise<void>;
export {};