export declare type Subscriber<T> = (value: T) => void;

export declare type Unsubscriber = () => void;

export declare type Updater<T> = (value?: T) => T;

export declare type Invalidator<T> = (value?: T) => void;

export declare type SubscribeInvalidateTuple<T> = [Subscriber<T>, Invalidator<T>];

export declare type StartStopNotifier<T> = (set: Subscriber<T>) => Unsubscriber | void;

export interface Readable<T> {

/**

* Get value and inform subscribers.

*/

get(): T;

/**

* Subscribe on value changes.

* @param run subscription callback

* @param invalidate cleanup callback

*/

subscribe(run: Subscriber<T>, invalidate?: Invalidator<T>): Unsubscriber;

}

export interface Writable<T> extends Readable<T> {

/**

* Set value and inform subscribers.

* @param value to set

*/

set(value?: T): void;

/**

* Update value using callback and inform subscribers.

* @param updater callback

*/

update(updater: Updater<T>): void;

}

/** One or more `Readable`s. */

export declare type Stores = Readable<any> | [Readable<any>, ...Array<Readable<any>>];

/** One or more values from `Readable` stores. */

export declare type StoresValues<T> = T extends Readable<infer U> ? U : {

[K in keyof T]: T[K] extends Readable<infer U> ? U : never;

};