export declare function reduce<T, R = T>(source: AsyncIterable<T>, accumulator: (previousValue: R, currentValue: T, currentIndex: number) => R | Promise<R>, seed?: never[]): Promise<R>;
export declare function reduce<T, R = T>(source: AsyncIterable<T>, accumulator: (previousValue: R, currentValue: T, currentIndex: number) => R | Promise<R>, seed?: R): Promise<R>;