import { E as ExactRecord } from './ExactRecord-or8-oNP7.js';
import './IfBoundedRecord-WIX9x_oz.js';
import 'type-fest';

/**
 * Converts a list of objects into an object indexing the objects by the given
 * key.
 *
 * There are several other functions that could be used to build an object from
 * an array:
 * * `fromKeys` - Builds an object from an array of *keys* and a mapper for values.
 * * `pullObject` - Builds an object from an array of items with mappers for *both* keys and values.
 * * `fromEntries` - Builds an object from an array of key-value pairs.
 * * `mapToObj` - Builds an object from an array of items and a single mapper for key-value pairs.
 * Refer to the docs for more details.
 *
 * @param data - The array.
 * @param mapper - The indexing function.
 * @signature
 *    R.indexBy(array, fn)
 * @example
 *    R.indexBy(['one', 'two', 'three'], x => x.length) // => {3: 'two', 5: 'three'}
 * @dataFirst
 * @category Array
 */
declare function indexBy<T, K extends PropertyKey>(data: ReadonlyArray<T>, mapper: (item: T, index: number, data: ReadonlyArray<T>) => K): ExactRecord<K, T>;
/**
 * Converts a list of objects into an object indexing the objects by the given
 * key.
 *
 * There are several other functions that could be used to build an object from
 * an array:
 * * `fromKeys` - Builds an object from an array of *keys* and a mapper for values.
 * * `pullObject` - Builds an object from an array of items with mappers for *both* keys and values.
 * * `fromEntries` - Builds an object from an array of key-value pairs.
 * * `mapToObj` - Builds an object from an array of items and a single mapper for key-value pairs.
 * Refer to the docs for more details.
 *
 * @param mapper - The indexing function.
 * @signature
 *    R.indexBy(fn)(array)
 * @example
 *    R.pipe(
 *      ['one', 'two', 'three'],
 *      R.indexBy(x => x.length)
 *    ) // => {3: 'two', 5: 'three'}
 * @dataLast
 * @category Array
 */
declare function indexBy<T, K extends PropertyKey>(mapper: (item: T, index: number, data: ReadonlyArray<T>) => K): (data: ReadonlyArray<T>) => ExactRecord<K, T>;

export { indexBy };