/**
 * Removes empty keys from an object.
 *
 * @remark
 * - Empty keys are keys with null, undefined, empty string, empty array, or empty object values.
 * - If `keysToKeep` is provided, it will not remove empty keys that match the provided keys.
 *
 * @param obj - The object to remove empty keys from.
 * @param keysToKeep - The keys to keep even if they are empty (optional).
 * @returns A new object with empty keys removed.
 *
 * @example
 * ```ts
 * const obj = {
 *  name: "John",
 *  age: 23,
 *  address: {
 *  street: "123 Main St.",
 *  city: "New York",
 *  state: "NY",
 *  zip: "",
 *  },
 * };
 *
 * removeEmptyKeys(obj);
 * // {
 * //   name: "John",
 * //   age: 23,
 * //   address: {
 *  //    street: "123 Main St.",
 * //     city: "New York",
 * //     state: "NY",
 * //   },
 * // }
 *
 * removeEmptyKeys(obj, ["address.zip"]);
 * // {
 * //   name: "John",
 * //   age: 23,
 * //   address: {
 * //     street: "123 Main St.",
 * //     city: "New York",
 * //     state: "NY",
 * //     zip: "",
 * //   },
 * // }
 * ```
 */
export declare function removeEmptyKeys<T extends Record<string, any>>(obj: T, keysToKeep?: string[]): T;