import { EmitterValue } from 'node-on';
export declare type WaitFn = (cb: () => void) => () => void;
export declare type UnsubFn = (() => void) | undefined;
export interface IObserver {
    next: (chunk: any) => void;
    error?: (err: Error) => void;
    complete?: () => void;
}
export interface IObserverEx {
    next: (chunk: EmitterValue) => void;
    error?: (err: EmitterValue) => void;
    complete?: () => void;
}
export interface IAsyncObserver {
    next: (chunk: any) => Promise<void>;
    error?: (err: Error) => Promise<void> | void;
    complete?: () => Promise<void> | void;
}
export interface IAsyncObserverEx {
    next: (chunk: EmitterValue) => Promise<void>;
    error?: (err: EmitterValue) => Promise<void> | void;
    complete?: () => Promise<void> | void;
}