/**
 * Adds unique values to an array.
 *
 * @param arr the array to add to.
 * @param values the values to add.
 */
export declare const pushToIfMissing: <T>(arr: T[], ...values: T[]) => T[];
/**
 * Removes values from an array if they are present.
 *
 * @param arr the array to remove from.
 * @param values the values to remove.
 */
export declare const removeFromIfPresent: <T>(arr: T[], ...values: T[]) => T[];