import { Observable } from 'rxjs';
import { BuilderState } from '../types';
/**
 *
 * @param tag
 * @param states
 * @param project
 */
export declare function joinBuilderStates<T, R>(tag: string, states: Array<BuilderState<T>>, project: (...args: T[]) => Observable<BuilderState<R>>): Observable<BuilderState<R>>;