import { IObservable } from '../internal/Observable';
import { IObserver } from '../internal/Observer';
import { ISubscription } from '../internal/Subscription';
import { IScheduler } from '../schedulers/Scheduler';
export declare type TOnNext<T> = {
    (value: T): void;
} | IObserver<T>;
export declare type TSource<T> = IObservable<T>;
export declare type TResult = ISubscription;
export declare type ForEachType = {
    <T>(onNext: TOnNext<T>, source: TSource<T>, scheduler?: IScheduler): TResult;
    <T>(onNext: TOnNext<T>): {
        (source: TSource<T>, scheduler?: IScheduler): TResult;
    };
};
export declare const forEach: ForEachType;