import { ddpReactiveCollection } from './ddpReactiveCollection';
/**
 * A reducer class for a reactive document.
 * @constructor
 */
export declare class ddpReducer<RArgs extends [any[], any, number, any[]], RResult, RInit, TCol> {
    private _ddpReactiveCollectionInstance;
    private readonly _reducer;
    private _started;
    private readonly _data;
    private _tickers;
    private readonly _initialValue;
    constructor(ddpReactiveCollectionInstance: ddpReactiveCollection<TCol>, reducer: (...args: RArgs) => RResult, initialValue: RInit);
    /**
   * Forcibly reduces reactive data.
   */
    doReduce(): void;
    /**
   * Starts reactiveness for the reduced value of the collection.
   * This method is being called on instance creation.
   */
    start(): void;
    /**
   * Stops reactiveness.
   */
    stop(): void;
    /**
   * Returns reactive reduce.
   */
    data(): Record<string, any>;
    /**
   * Runs a function every time a change occurs.
   * @param {Function} f - Function which recieves a reduced value at each change.
   */
    onChange(f: {}): {
        start: () => void;
        stop: () => void;
    };
}