import { KVGroupTransform } from '../types/base';
import { Mapper } from 'augmentative-iterable';
import { AnyMapper } from '../types-internal';
import { Choose } from '../types';
/**
 * Returns a functions that make the group operations to get only one item, per group key,
 * The item kept is the preferred one, according to a given choosing criteria,
 * @param choose must return the preferred value over two provided
 */
export declare function getGroupingTopHit<K, T>(choose: Choose<T>): KVGroupTransform<K, T>;
/**
 * Returns a functions that make the group operations get distinct items, according to a giving criteria,
 * keeping the preferred one, according to a given choosing criteria,
 * @param distinct must return the distinction key. The distinction is respected by group
 * @param choose must return the preferred value over two provided
 * @param mapper The property name you want to map for the value
 */
export declare function getGroupingTopHit<K, T, KT extends keyof T>(distinct: AnyMapper<T>, choose: Choose<T[KT]>, mapper: KT): KVGroupTransform<K, T, T[KT][]>;
/**
 * Returns a functions that make the group operations get distinct items, according to a giving criteria,
 * keeping the preferred one, according to a given choosing criteria,
 * @param distinct must return the distinction key. The distinction is respected by group
 * @param choose must return the preferred value over two provided
 * @param mapper If informed, the mapping operation to define the grouping value. If not, the original value is assumed
 */
export declare function getGroupingTopHit<K, T, NewT = T>(distinct: AnyMapper<T>, choose: Choose<NewT>, mapper?: Mapper<T, NewT>): KVGroupTransform<K, T, NewT>;