export interface SetItemOptions {
    /** Expiration Date */
    expires?: Date;
    /** Maximum age in seconds */
    maxAge?: number;
}
/**
 * CookieStorage is a handler for reading and writing cookies in Javascript
 * Usage is similar to `localStorage` and `sessionStorage`
 */
export declare class CookieStorage implements Storage {
    get length(): number;
    /**
     * Retrieve an item from the stored cookie
     * @param key The key of the cookie to be retrieved
     * @returns The value of the cookie, `null` if it doesn't exist
     */
    getItem(key: string): string;
    /**
     * Sets an item to the stored cookie
     * @param key The key of the cookie to be set
     * @param value The value of the cookie
     * @param options Available options are `expires`, `maxAge` and `secure` @see SetItemOptions interface for reference
     * @returns `true` if successful
     */
    setItem(key: string, value: any, options?: SetItemOptions): boolean;
    /**
     * Remove an item from the stored cookie
     * @param {string} key The key of the cookie to be removed
     * @returns {boolean} `true` if successful
     */
    removeItem(key: string): boolean;
    /**
     * Verifies if an item exists in the cookie
     * @param {string} key The key of the item to be verified
     * @returns {boolean} `true` if it exists
     */
    hasItem(key: string): boolean;
    clear(): void;
    /**
     * Retrives the list of keys in the stored cookie
     * @returns The list of keys in the stored cookie
     */
    keys(): Array<string>;
    /**
     * @param index The index of the array of keys
     * @returns The key at the given index, if any
     */
    key(index: number): string;
}