import { BuilderFunction, Reducer } from '../types';
import { ActorEvent } from '../types/actor-event.type';
/**
 * Utility function to create reducers
 * @param initialState reducer initial state
 * @param builderFunction a function that takes an instance of `ReducerBuilder<S>` as parameter to generate the reducer
 * @returns a reducer function
 * @example
 *
 * import { createEvent, createReducer } from 'reactive-actor';
 *
 * export interface LayoutState {
 *   loading: boolean;
 *   error: string;
 * }
 *
 * export const layoutInitialState: LayoutState = {
 *   loading: false,
 *   error: '',
 * };
 *
 * export const startLoader = createEvent('START_LOADER');
 *
 * export const stopLoader = createEvent('STOP_LOADER');
 *
 * export const layoutReducer = createReducer(layoutInitialState, (builder) =>
 *   builder
 *     .addCase(startLoader, (state) => ({ ...state, loading: true }))
 *     .addCase(stopLoader, (state) => ({ ...state, loading: false }))
 * );
 *
 */
export declare function createReducer<TState, TEvent extends ActorEvent = ActorEvent>(initialState: TState, builderFunction: BuilderFunction<TState>): Reducer<TState, TEvent>;