/** @see https://developer.mozilla.org/en-US/docs/Web/API/Storage for native specifications */
export declare class LocalStorageUtility {
    readonly localStorageSupported: boolean;
    /** Integer number */
    readonly version?: number;
    /** Passive expiration time in ms */
    readonly expiration?: number;
    readonly prefix: string;
    private CONTROL_ITEM_KEY;
    constructor(version?: number, expiration?: number, prefix?: string);
    get length(): number;
    key(n: number): string | undefined;
    getItem<T = any>(key: string): T | null;
    setItem<T>(key: string, value: T): void;
    removeItem(key: string): void;
    clear(): void;
    getAll(): any[];
    private getAllKeys;
    private filterStorage;
    /** Wrapper for localStorage.getItem that parses the result */
    private get;
    /** Wrapper for localStorage.setItem that stringify the value */
    private set;
    private checkIfExpired;
    private getControlItem;
    private setControlItem;
    private checkIfOldVersion;
}