import type { List, ValueIteratee } from 'lodash';
/**
 * Creates an object composed of keys generated from the results of running each element of collection through
 * iteratee. The corresponding value of each key is an array of the elements responsible for generating the
 * key. The iteratee is invoked with one argument: (value).
 *
 * @param collection - The collection to iterate over.
 * @param iteratee - The function invoked per iteration.
 * @returns Returns the composed aggregate object.
 */
export declare function groupBy<T>(collection: ArrayLike<T> | null | undefined, iteratee?: ValueIteratee<T>): {
    [index: string]: T[];
};
/**
 * Creates an array of elements split into two groups, the first of which contains elements predicate returns truthy for,
 * while the second of which contains elements predicate returns falsey for.
 * The predicate is invoked with three arguments: (value, index|key, collection).
 *
 * @param collection - The collection to iterate over.
 * @param callback - The function called per iteration.
 * @returns Returns the array of grouped elements.
 */
export declare function partition<T>(collection: List<T> | null | undefined, callback: ValueIteratee<T>): [T[], T[]];