/**
 * Creates an object composed of keys generated from the specified property of each element.
 *
 * @example
 * const users = [{ id: 'a', name: 'Alice' }, { id: 'b', name: 'Bob' }];
 * keyBy(users, 'id') // { a: { id: 'a', name: 'Alice' }, b: { id: 'b', name: 'Bob' } }
 */
export declare function keyBy<T extends Record<string, any>, K extends keyof T>(array: readonly T[], key: K): Record<string, T>;