export type StorageItemMapOptions<T> = {
    area?: chrome.storage.AreaName;
    defaultValue?: T;
};
export declare class StorageItemMap<
/** Only specify this if you don't have a default value */
Base, 
/** The return type will be undefined unless you provide a default value */
Return = Base | undefined> {
    #private;
    readonly prefix: `${string}:::`;
    readonly areaName: chrome.storage.AreaName;
    readonly defaultValue?: Return;
    constructor(key: string, { area, defaultValue, }?: StorageItemMapOptions<Exclude<Return, undefined>>);
    has(secondaryKey: string): Promise<boolean>;
    get(secondaryKey: string): Promise<Return>;
    set(secondaryKey: string, value: Exclude<Return, undefined>): Promise<void>;
    remove(secondaryKey: string): Promise<void>;
    /** @deprecated Only here to match the Map API; use `remove` instead */
    delete(secondaryKey: string): Promise<void>;
    keys(): Promise<string[]>;
    clear(): Promise<void>;
    entries(): AsyncIterableIterator<[string, Exclude<Return, undefined>]>;
    [Symbol.asyncIterator](): AsyncIterableIterator<[string, Exclude<Return, undefined>]>;
    onChanged(callback: (key: string, value: Exclude<Return, undefined>) => void, signal?: AbortSignal): void;
    private getRawStorageKey;
    private getSecondaryStorageKey;
}