export declare class _Crossbar {
    private listenersByCollection;
    private listenersByCollectionCount;
    private nextId;
    constructor(options: any);
    _collectionForMessage(msg: {
        collection?: any;
    }): string;
    listen(trigger: any, callback: any): {
        stop: () => void;
    };
    fire(notification: Record<string, any>): void;
    _matches(notification: Record<string, any>, trigger: Record<string, any>): boolean;
}
export declare const _InvalidationCrossbar: _Crossbar;