import { Entry, EventSchema, Registry } from './types';
export declare class EventContractBuilder<R extends EventSchema, T extends Registry<R> = {}> {
    private readonly jsonObject;
    private constructor();
    static create<K extends EventSchema>(): EventContractBuilder<K>;
    build(): T;
    required<K extends string, V extends R>(key: K, value: V): EventContractBuilder<R, T & {
        [k in K]: Entry<V>;
    }>;
    optional<K extends string, V extends R>(key: K, value: V): EventContractBuilder<R, T & {
        [k in K]: Entry<V>;
    }>;
}