type GroupByOptions<TRecord, TKey> = {
    keyExtractor: (record: TRecord) => TKey;
    records: Array<TRecord>;
};
/**
 * @description
 * Use helper to group records by a key derived from each record.
 *
 * It returns a `Map` where keys are group keys and values are record sets of grouped records.
 */
export declare const groupBy: <TRecord, TKey>(options: GroupByOptions<TRecord, TKey>) => Map<TKey, Array<TRecord>>;
export {};