import { type MaybePromise } from '@augment-vir/core';
/**
 * Polyfill for `Object.groupBy`:
 * https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Object/groupBy
 *
 * @category Array
 * @category Object
 * @example
 *
 * ```ts
 * import {arrayToObject} from '@augment-vir/common';
 *
 * const result = arrayToObject(
 *     [
 *         'a',
 *         'b',
 *     ],
 *     (value) => `key-${value}`,
 * );
 * // result is `{key-a: ['a'], key-b: ['b']}`
 * ```
 */
export declare function groupArrayBy<ElementType, NewKey extends PropertyKey>(inputArray: ReadonlyArray<ElementType>, callback: (value: ElementType, index: number, originalArray: ReadonlyArray<ElementType>) => NewKey): Partial<Record<NewKey, ElementType[]>>;
export declare function arrayToObject<ElementType, NewKey extends PropertyKey, NewValue>(inputArray: ReadonlyArray<ElementType>, callback: (value: ElementType, index: number, originalArray: ReadonlyArray<ElementType>) => Promise<{
    key: NewKey;
    value: NewValue;
} | undefined>): Promise<Partial<Record<NewKey, NewValue>>>;
export declare function arrayToObject<ElementType, NewKey extends PropertyKey, NewValue>(inputArray: ReadonlyArray<ElementType>, callback: (value: ElementType, index: number, originalArray: ReadonlyArray<ElementType>) => {
    key: NewKey;
    value: NewValue;
} | undefined): Partial<Record<NewKey, NewValue>>;
export declare function arrayToObject<ElementType, NewKey extends PropertyKey, NewValue>(inputArray: ReadonlyArray<ElementType>, callback: (value: ElementType, index: number, originalArray: ReadonlyArray<ElementType>) => MaybePromise<{
    key: NewKey;
    value: NewValue;
} | undefined>): MaybePromise<Partial<Record<NewKey, NewValue>>>;