import { TaskEventModel } from "./models/TaskEventModel";
import { Context, ObserverFilter, ObserverHandler } from "../persistence/index";
import { TaskContext } from "./TaskContext";
import { Observer } from "../interfaces/index";
export declare class TaskEventBus extends ObserverHandler<TaskContext> {
    protected readonly listeners: Set<(evt: TaskEventModel) => void>;
    observe(observer: Observer, filter?: ObserverFilter): void;
    unObserve(observer: Observer): void;
    on(observer: Observer): () => void;
    emit(evt: TaskEventModel, ctx: Context): void;
}