import { AsyncIterableLike } from "../async-like";
export type GroupFn<T, This, Parent> = (this: This, value: T, parent: Parent) => string;
export type GroupAsyncFn<T, This, Parent> = (this: This, value: T, parent: Parent) => Promise<string> | string;
export declare function group<T, This, Parent>(iterable: Iterable<T>, callbackFn: GroupFn<T, This, Parent>, thisValue?: This, parent?: Parent): IterableIterator<IterableIterator<T>>;
export declare function asyncGroup<T, This, Parent>(iterable: AsyncIterableLike<T>, callbackFn: GroupAsyncFn<T, This, Parent>, thisValue?: This, parent?: Parent): AsyncIterableIterator<AsyncIterableIterator<T>>;