/**
 * Returns a reduced array based on given comparator (if none given, will use `Type.is`)
 * @param arr Array to be reduced
 * @param comparator comparator function to use `(arg1, arg2)=>boolean`
 * @returns
 */
export declare function uniqueFilter<T>(arr: Array<T>, comparator?: (arg1: T, arg2: T) => boolean): Array<T>;