import { ActionCreator, ActionType } from "./action";
import { Action } from "./types";
export declare type On<S> = {
    reducer: (state: S, action: Action) => S;
    types: string[];
};
export declare type OnReducer<S, C extends ActionCreator[]> = (state: S, action: ActionType<C[number]>) => S;
export declare type Reducer<S> = (state: S | undefined, action: Action) => S;
export declare function on<C1 extends ActionCreator, S>(creator1: C1, reducer: OnReducer<S, [C1]>): On<S>;
export declare function on<C1 extends ActionCreator, C2 extends ActionCreator, S>(creator1: C1, creator2: C2, reducer: OnReducer<S, [C1, C2]>): On<S>;
export declare function on<C1 extends ActionCreator, C2 extends ActionCreator, C3 extends ActionCreator, S>(creator1: C1, creator2: C2, creator3: C3, reducer: OnReducer<S, [C1, C2, C3]>): On<S>;
export declare function on<S, C extends {
    type: string;
    action: Action;
}>(...args: (C | ((state: S, action: C["action"]) => S))[]): On<S>;
export declare function reducer<S>(initialState: S, ...ons: On<S>[]): Reducer<S>;