Type Alias ReducersMapObject<S, A, PreloadedState>

ReducersMapObject: keyof PreloadedState extends keyof S
    ? {
        [K in keyof S]: Reducer<
            S[K],
            A,
            K extends keyof PreloadedState ? PreloadedState[K] : never,
        >
    }
    : never

Object whose values correspond to different reducer functions.