import { Future } from '../classes/Future';
import { Result } from '../classes/Result';
export declare const ITERATOR_EXHAUSTED: unique symbol;
type MP<T> = T | PromiseLike<T>;
type MR<T> = T | Result<T>;
type MPP<T> = MP<MP<T> | MR<T>>;
type MRR<T> = MR<MP<T> | MR<T>>;
type MPR<T> = MP<MPP<T> | MRR<T>>;
export type AsyncGenerator<I> = () => MPR<I>;
export type AsyncStepper<I> = (previous: I) => MPR<I>;
export type AsyncIterator<I, O> = (input: I) => MPR<O>;
export type AsyncValidator<O> = (output: O) => MPR<boolean>;
export declare function iterateAsync<I, O>(
	genfn: AsyncGenerator<I>,
	iterator: AsyncIterator<I, O>,
	validator: AsyncValidator<O>
): Future<O>;
export declare function iterateAsync<I, O>(
	iterable: Iterable<I>,
	iterator: AsyncIterator<I, O>,
	validator: AsyncValidator<O>
): Future<O>;
export declare function iterateAsync<I, O>(
	init: AsyncGenerator<I>,
	step: AsyncStepper<I>,
	iterator: AsyncIterator<I, O>,
	validator: AsyncValidator<O>
): Future<O>;
export declare function iterateAsyncIterableWrapper<I, O>(
	iterable: Iterable<I>,
	iterator: AsyncIterator<I, O>,
	validator: AsyncValidator<O>
): Future<O>;
export declare function iterateAsyncResultWrapper<I, O>(
	init: AsyncGenerator<I>,
	step: AsyncStepper<I>,
	iterator: AsyncIterator<I, O>,
	validator?: AsyncValidator<O>
): Future<O>;
export declare function unwrap<T>(item: MPR<T>): Promise<T>;
export declare function iterateAsyncImpl<I, O>(
	init: AsyncGenerator<I>,
	step: AsyncStepper<I>,
	iterator: AsyncIterator<I, O>,
	validator?: AsyncValidator<O>
): Promise<O>;
export {};