import { EventData } from 'web3-eth-contract';
import { Subscription } from 'web3-core-subscriptions';
/**
 * If the event is not yet subscribed (and so, has 'id' value of null) the 'unsubscribe' call will not work and the CB will get called.
 * Therefore we will wait until it is connected in order to disconnect it.
 */
export declare function getUnsubscribePromise(eventEmitter: Subscription<EventData>): Promise<boolean | undefined>;