import { Collector, BaseCollector } from "../collector";
import { Mapper } from "../collections/groupingBy";
export declare class FlatMappingCollector<T, U, A, R> extends BaseCollector<T, A, R> {
    protected mapper: Mapper<T, Iterable<U>>;
    protected collector: Collector<U, A, R>;
    constructor(mapper: Mapper<T, Iterable<U>>, collector: Collector<U, A, R>);
    supply(): A;
    accumulate(container: A, item: T): void;
    combine(container1: A, container2: A): A;
    finish(container: A): R;
}
export declare function flatMapping<T, U>(mapper: Mapper<T, Iterable<U>>): Collector<T, U[], U[]>;
export declare function flatMapping<T, U, A, R>(mapper: Mapper<T, Iterable<U>>, collector?: Collector<U, A, R>): Collector<T, A, R>;