import { Awaitable } from 'justypes';
export declare function reduceAsync<T>(iterable: Iterable<T> | AsyncIterable<T>, fn: (accumulator: Awaited<T>, currentValue: Awaited<T>, index: number) => Awaitable<Awaited<T>>): Promise<Awaited<T>>;
export declare function reduceAsync<T, U>(iterable: Iterable<T> | AsyncIterable<T>, fn: (accumulator: Awaited<U>, currentValue: Awaited<T>, index: number) => Awaitable<U>, initialValue: U): Promise<Awaited<U>>;