/** * An *action* is a plain object that represents an intention to change the * state. Actions are the only way to get data into the store. Any data, * whether from UI events, network callbacks, or other sources such as * WebSockets needs to eventually be dispatched as actions. * * Actions must have a `type` field that indicates the type of action being * performed. Types can be defined as constants and imported from another * module. These must be strings, as strings are serializable. * * Other than `type`, the structure of an action object is really up to you. * If you're interested, check out Flux Standard Action for recommendations on * how actions should be constructed. * * @template T the type of the action's `type` tag. */ type Action = { type: T; }; /** * An Action type which accepts any other properties. * This is mainly for the use of the `Reducer` type. * This is not part of `Action` itself to prevent types that extend `Action` from * having an index signature. */ interface UnknownAction extends Action { [extraProps: string]: unknown; } /** * An Action type which accepts any other properties. * This is mainly for the use of the `Reducer` type. * This is not part of `Action` itself to prevent types that extend `Action` from * having an index signature. * @deprecated use Action or UnknownAction instead */ interface AnyAction extends Action { [extraProps: string]: any; } /** * An *action creator* is, quite simply, a function that creates an action. Do * not confuse the two terms—again, an action is a payload of information, and * an action creator is a factory that creates an action. * * Calling an action creator only produces an action, but does not dispatch * it. You need to call the store's `dispatch` function to actually cause the * mutation. Sometimes we say *bound action creators* to mean functions that * call an action creator and immediately dispatch its result to a specific * store instance. * * If an action creator needs to read the current state, perform an API call, * or cause a side effect, like a routing transition, it should return an * async action instead of an action. * * @template A Returned action type. */ interface ActionCreator { (...args: P): A; } /** * Object whose values are action creator functions. */ interface ActionCreatorsMapObject { [key: string]: ActionCreator; } /** * A *reducer* is a function that accepts * an accumulation and a value and returns a new accumulation. They are used * to reduce a collection of values down to a single value * * Reducers are not unique to Redux—they are a fundamental concept in * functional programming. Even most non-functional languages, like * JavaScript, have a built-in API for reducing. In JavaScript, it's * `Array.prototype.reduce()`. * * In Redux, the accumulated value is the state object, and the values being * accumulated are actions. Reducers calculate a new state given the previous * state and an action. They must be *pure functions*—functions that return * the exact same output for given inputs. They should also be free of * side-effects. This is what enables exciting features like hot reloading and * time travel. * * Reducers are the most important concept in Redux. * * *Do not put API calls into reducers.* * * @template S The type of state consumed and produced by this reducer. * @template A The type of actions the reducer can potentially respond to. * @template PreloadedState The type of state consumed by this reducer the first time it's called. */ type Reducer = (state: S | PreloadedState | undefined, action: A) => S; /** * Object whose values correspond to different reducer functions. * * @template S The combined state of the reducers. * @template A The type of actions the reducers can potentially respond to. * @template PreloadedState The combined preloaded state of the reducers. */ type ReducersMapObject = keyof PreloadedState extends keyof S ? { [K in keyof S]: Reducer; } : never; /** * Infer a combined state shape from a `ReducersMapObject`. * * @template M Object map of reducers as provided to `combineReducers(map: M)`. */ type StateFromReducersMapObject = M[keyof M] extends Reducer | undefined ? { [P in keyof M]: M[P] extends Reducer ? S : never; } : never; /** * Infer reducer union type from a `ReducersMapObject`. * * @template M Object map of reducers as provided to `combineReducers(map: M)`. */ type ReducerFromReducersMapObject = M[keyof M] extends Reducer | undefined ? M[keyof M] : never; /** * Infer action type from a reducer function. * * @template R Type of reducer. */ type ActionFromReducer = R extends Reducer ? A : never; /** * Infer action union type from a `ReducersMapObject`. * * @template M Object map of reducers as provided to `combineReducers(map: M)`. */ type ActionFromReducersMapObject = ActionFromReducer>; /** * Infer a combined preloaded state shape from a `ReducersMapObject`. * * @template M Object map of reducers as provided to `combineReducers(map: M)`. */ type PreloadedStateShapeFromReducersMapObject = M[keyof M] extends Reducer | undefined ? { [P in keyof M]: M[P] extends (inputState: infer InputState, action: UnknownAction) => any ? InputState : never; } : never; /** * A *dispatching function* (or simply *dispatch function*) is a function that * accepts an action or an async action; it then may or may not dispatch one * or more actions to the store. * * We must distinguish between dispatching functions in general and the base * `dispatch` function provided by the store instance without any middleware. * * The base dispatch function *always* synchronously sends an action to the * store's reducer, along with the previous state returned by the store, to * calculate a new state. It expects actions to be plain objects ready to be * consumed by the reducer. * * Middleware wraps the base dispatch function. It allows the dispatch * function to handle async actions in addition to actions. Middleware may * transform, delay, ignore, or otherwise interpret actions or async actions * before passing them to the next middleware. * * @template A The type of things (actions or otherwise) which may be * dispatched. */ interface Dispatch { (action: T, ...extraArgs: any[]): T; } /** * Function to remove listener added by `Store.subscribe()`. */ interface Unsubscribe { (): void; } type ListenerCallback = () => void; declare global { interface SymbolConstructor { readonly observable: symbol; } } /** * A minimal observable of state changes. * For more information, see the observable proposal: * https://github.com/tc39/proposal-observable */ type Observable = { /** * The minimal observable subscription method. * @param {Object} observer Any object that can be used as an observer. * The observer object should have a `next` method. * @returns {subscription} An object with an `unsubscribe` method that can * be used to unsubscribe the observable from the store, and prevent further * emission of values from the observable. */ subscribe: (observer: Observer) => { unsubscribe: Unsubscribe; }; [Symbol.observable](): Observable; }; /** * An Observer is used to receive data from an Observable, and is supplied as * an argument to subscribe. */ type Observer = { next?(value: T): void; }; /** * A store is an object that holds the application's state tree. * There should only be a single store in a Redux app, as the composition * happens on the reducer level. * * @template S The type of state held by this store. * @template A the type of actions which may be dispatched by this store. * @template StateExt any extension to state from store enhancers */ interface Store { /** * Dispatches an action. It is the only way to trigger a state change. * * The `reducer` function, used to create the store, will be called with the * current state tree and the given `action`. Its return value will be * considered the **next** state of the tree, and the change listeners will * be notified. * * The base implementation only supports plain object actions. If you want * to dispatch a Promise, an Observable, a thunk, or something else, you * need to wrap your store creating function into the corresponding * middleware. For example, see the documentation for the `redux-thunk` * package. Even the middleware will eventually dispatch plain object * actions using this method. * * @param action A plain object representing “what changed”. It is a good * idea to keep actions serializable so you can record and replay user * sessions, or use the time travelling `redux-devtools`. An action must * have a `type` property which may not be `undefined`. It is a good idea * to use string constants for action types. * * @returns For convenience, the same action object you dispatched. * * Note that, if you use a custom middleware, it may wrap `dispatch()` to * return something else (for example, a Promise you can await). */ dispatch: Dispatch; /** * Reads the state tree managed by the store. * * @returns The current state tree of your application. */ getState(): S & StateExt; /** * Adds a change listener. It will be called any time an action is * dispatched, and some part of the state tree may potentially have changed. * You may then call `getState()` to read the current state tree inside the * callback. * * You may call `dispatch()` from a change listener, with the following * caveats: * * 1. The subscriptions are snapshotted just before every `dispatch()` call. * If you subscribe or unsubscribe while the listeners are being invoked, * this will not have any effect on the `dispatch()` that is currently in * progress. However, the next `dispatch()` call, whether nested or not, * will use a more recent snapshot of the subscription list. * * 2. The listener should not expect to see all states changes, as the state * might have been updated multiple times during a nested `dispatch()` before * the listener is called. It is, however, guaranteed that all subscribers * registered before the `dispatch()` started will be called with the latest * state by the time it exits. * * @param listener A callback to be invoked on every dispatch. * @returns A function to remove this change listener. */ subscribe(listener: ListenerCallback): Unsubscribe; /** * Replaces the reducer currently used by the store to calculate the state. * * You might need this if your app implements code splitting and you want to * load some of the reducers dynamically. You might also need this if you * implement a hot reloading mechanism for Redux. * * @param nextReducer The reducer for the store to use instead. */ replaceReducer(nextReducer: Reducer): void; /** * Interoperability point for observable/reactive libraries. * @returns {observable} A minimal observable of state changes. * For more information, see the observable proposal: * https://github.com/tc39/proposal-observable */ [Symbol.observable](): Observable; } type UnknownIfNonSpecific = {} extends T ? unknown : T; /** * A store creator is a function that creates a Redux store. Like with * dispatching function, we must distinguish the base store creator, * `createStore(reducer, preloadedState)` exported from the Redux package, from * store creators that are returned from the store enhancers. * * @template S The type of state to be held by the store. * @template A The type of actions which may be dispatched. * @template PreloadedState The initial state that is passed into the reducer. * @template Ext Store extension that is mixed in to the Store type. * @template StateExt State extension that is mixed into the state type. */ interface StoreCreator { (reducer: Reducer, enhancer?: StoreEnhancer): Store> & Ext; (reducer: Reducer, preloadedState?: PreloadedState | undefined, enhancer?: StoreEnhancer): Store> & Ext; } /** * A store enhancer is a higher-order function that composes a store creator * to return a new, enhanced store creator. This is similar to middleware in * that it allows you to alter the store interface in a composable way. * * Store enhancers are much the same concept as higher-order components in * React, which are also occasionally called “component enhancers”. * * Because a store is not an instance, but rather a plain-object collection of * functions, copies can be easily created and modified without mutating the * original store. There is an example in `compose` documentation * demonstrating that. * * Most likely you'll never write a store enhancer, but you may use the one * provided by the developer tools. It is what makes time travel possible * without the app being aware it is happening. Amusingly, the Redux * middleware implementation is itself a store enhancer. * * @template Ext Store extension that is mixed into the Store type. * @template StateExt State extension that is mixed into the state type. */ type StoreEnhancer = (next: StoreEnhancerStoreCreator) => StoreEnhancerStoreCreator; type StoreEnhancerStoreCreator = (reducer: Reducer, preloadedState?: PreloadedState | undefined) => Store & Ext; /** * @deprecated * * **We recommend using the `configureStore` method * of the `@reduxjs/toolkit` package**, which replaces `createStore`. * * Redux Toolkit is our recommended approach for writing Redux logic today, * including store setup, reducers, data fetching, and more. * * **For more details, please read this Redux docs page:** * **https://redux.js.org/introduction/why-rtk-is-redux-today** * * `configureStore` from Redux Toolkit is an improved version of `createStore` that * simplifies setup and helps avoid common bugs. * * You should not be using the `redux` core package by itself today, except for learning purposes. * The `createStore` method from the core `redux` package will not be removed, but we encourage * all users to migrate to using Redux Toolkit for all Redux code. * * If you want to use `createStore` without this visual deprecation warning, use * the `legacy_createStore` import instead: * * `import { legacy_createStore as createStore} from 'redux'` * */ declare function createStore(reducer: Reducer, enhancer?: StoreEnhancer): Store> & Ext; /** * @deprecated * * **We recommend using the `configureStore` method * of the `@reduxjs/toolkit` package**, which replaces `createStore`. * * Redux Toolkit is our recommended approach for writing Redux logic today, * including store setup, reducers, data fetching, and more. * * **For more details, please read this Redux docs page:** * **https://redux.js.org/introduction/why-rtk-is-redux-today** * * `configureStore` from Redux Toolkit is an improved version of `createStore` that * simplifies setup and helps avoid common bugs. * * You should not be using the `redux` core package by itself today, except for learning purposes. * The `createStore` method from the core `redux` package will not be removed, but we encourage * all users to migrate to using Redux Toolkit for all Redux code. * * If you want to use `createStore` without this visual deprecation warning, use * the `legacy_createStore` import instead: * * `import { legacy_createStore as createStore} from 'redux'` * */ declare function createStore(reducer: Reducer, preloadedState?: PreloadedState | undefined, enhancer?: StoreEnhancer): Store> & Ext; /** * Creates a Redux store that holds the state tree. * * **We recommend using `configureStore` from the * `@reduxjs/toolkit` package**, which replaces `createStore`: * **https://redux.js.org/introduction/why-rtk-is-redux-today** * * The only way to change the data in the store is to call `dispatch()` on it. * * There should only be a single store in your app. To specify how different * parts of the state tree respond to actions, you may combine several reducers * into a single reducer function by using `combineReducers`. * * @param {Function} reducer A function that returns the next state tree, given * the current state tree and the action to handle. * * @param {any} [preloadedState] The initial state. You may optionally specify it * to hydrate the state from the server in universal apps, or to restore a * previously serialized user session. * If you use `combineReducers` to produce the root reducer function, this must be * an object with the same shape as `combineReducers` keys. * * @param {Function} [enhancer] The store enhancer. You may optionally specify it * to enhance the store with third-party capabilities such as middleware, * time travel, persistence, etc. The only store enhancer that ships with Redux * is `applyMiddleware()`. * * @returns {Store} A Redux store that lets you read the state, dispatch actions * and subscribe to changes. */ declare function legacy_createStore(reducer: Reducer, enhancer?: StoreEnhancer): Store> & Ext; /** * Creates a Redux store that holds the state tree. * * **We recommend using `configureStore` from the * `@reduxjs/toolkit` package**, which replaces `createStore`: * **https://redux.js.org/introduction/why-rtk-is-redux-today** * * The only way to change the data in the store is to call `dispatch()` on it. * * There should only be a single store in your app. To specify how different * parts of the state tree respond to actions, you may combine several reducers * into a single reducer function by using `combineReducers`. * * @param {Function} reducer A function that returns the next state tree, given * the current state tree and the action to handle. * * @param {any} [preloadedState] The initial state. You may optionally specify it * to hydrate the state from the server in universal apps, or to restore a * previously serialized user session. * If you use `combineReducers` to produce the root reducer function, this must be * an object with the same shape as `combineReducers` keys. * * @param {Function} [enhancer] The store enhancer. You may optionally specify it * to enhance the store with third-party capabilities such as middleware, * time travel, persistence, etc. The only store enhancer that ships with Redux * is `applyMiddleware()`. * * @returns {Store} A Redux store that lets you read the state, dispatch actions * and subscribe to changes. */ declare function legacy_createStore(reducer: Reducer, preloadedState?: PreloadedState | undefined, enhancer?: StoreEnhancer): Store> & Ext; /** * Turns an object whose values are different reducer functions, into a single * reducer function. It will call every child reducer, and gather their results * into a single state object, whose keys correspond to the keys of the passed * reducer functions. * * @template S Combined state object type. * * @param reducers An object whose values correspond to different reducer * functions that need to be combined into one. One handy way to obtain it * is to use `import * as reducers` syntax. The reducers may never * return undefined for any action. Instead, they should return their * initial state if the state passed to them was undefined, and the current * state for any unrecognized action. * * @returns A reducer function that invokes every reducer inside the passed * object, and builds a state object with the same shape. */ declare function combineReducers(reducers: M): M[keyof M] extends Reducer | undefined ? Reducer, ActionFromReducersMapObject, Partial>> : never; /** * Turns an object whose values are action creators, into an object with the * same keys, but with every function wrapped into a `dispatch` call so they * may be invoked directly. This is just a convenience method, as you can call * `store.dispatch(MyActionCreators.doSomething())` yourself just fine. * * For convenience, you can also pass an action creator as the first argument, * and get a dispatch wrapped function in return. * * @param actionCreators An object whose values are action * creator functions. One handy way to obtain it is to use `import * as` * syntax. You may also pass a single function. * * @param dispatch The `dispatch` function available on your Redux * store. * * @returns The object mimicking the original object, but with * every action creator wrapped into the `dispatch` call. If you passed a * function as `actionCreators`, the return value will also be a single * function. */ declare function bindActionCreators>(actionCreator: C, dispatch: Dispatch): C; declare function bindActionCreators, B extends ActionCreator>(actionCreator: A, dispatch: Dispatch): B; declare function bindActionCreators>(actionCreators: M, dispatch: Dispatch): M; declare function bindActionCreators(actionCreators: M, dispatch: Dispatch): N; interface MiddlewareAPI { dispatch: D; getState(): S; } /** * A middleware is a higher-order function that composes a dispatch function * to return a new dispatch function. It often turns async actions into * actions. * * Middleware is composable using function composition. It is useful for * logging actions, performing side effects like routing, or turning an * asynchronous API call into a series of synchronous actions. * * @template DispatchExt Extra Dispatch signature added by this middleware. * @template S The type of the state supported by this middleware. * @template D The type of Dispatch of the store where this middleware is * installed. */ interface Middleware<_DispatchExt = {}, // TODO: see if this can be used in type definition somehow (can't be removed, as is used to get final dispatch type) S = any, D extends Dispatch = Dispatch> { (api: MiddlewareAPI): (next: (action: unknown) => unknown) => (action: unknown) => unknown; } /** * Creates a store enhancer that applies middleware to the dispatch method * of the Redux store. This is handy for a variety of tasks, such as expressing * asynchronous actions in a concise manner, or logging every action payload. * * See `redux-thunk` package as an example of the Redux middleware. * * Because middleware is potentially asynchronous, this should be the first * store enhancer in the composition chain. * * Note that each middleware will be given the `dispatch` and `getState` functions * as named arguments. * * @param middlewares The middleware chain to be applied. * @returns A store enhancer applying the middleware. * * @template Ext Dispatch signature added by a middleware. * @template S The type of the state supported by a middleware. */ declare function applyMiddleware(): StoreEnhancer; declare function applyMiddleware(middleware1: Middleware): StoreEnhancer<{ dispatch: Ext1; }>; declare function applyMiddleware(middleware1: Middleware, middleware2: Middleware): StoreEnhancer<{ dispatch: Ext1 & Ext2; }>; declare function applyMiddleware(middleware1: Middleware, middleware2: Middleware, middleware3: Middleware): StoreEnhancer<{ dispatch: Ext1 & Ext2 & Ext3; }>; declare function applyMiddleware(middleware1: Middleware, middleware2: Middleware, middleware3: Middleware, middleware4: Middleware): StoreEnhancer<{ dispatch: Ext1 & Ext2 & Ext3 & Ext4; }>; declare function applyMiddleware(middleware1: Middleware, middleware2: Middleware, middleware3: Middleware, middleware4: Middleware, middleware5: Middleware): StoreEnhancer<{ dispatch: Ext1 & Ext2 & Ext3 & Ext4 & Ext5; }>; declare function applyMiddleware(...middlewares: Middleware[]): StoreEnhancer<{ dispatch: Ext; }>; type Func = (...a: T) => R; /** * Composes single-argument functions from right to left. The rightmost * function can take multiple arguments as it provides the signature for the * resulting composite function. * * @param funcs The functions to compose. * @returns A function obtained by composing the argument functions from right * to left. For example, `compose(f, g, h)` is identical to doing * `(...args) => f(g(h(...args)))`. */ declare function compose(): (a: R) => R; declare function compose(f: F): F; declare function compose(f1: (a: A) => R, f2: Func): Func; declare function compose(f1: (b: B) => R, f2: (a: A) => B, f3: Func): Func; declare function compose(f1: (c: C) => R, f2: (b: B) => C, f3: (a: A) => B, f4: Func): Func; declare function compose(f1: (a: any) => R, ...funcs: Function[]): (...args: any[]) => R; declare function compose(...funcs: Function[]): (...args: any[]) => R; declare function isAction(action: unknown): action is Action; /** * @param obj The object to inspect. * @returns True if the argument appears to be a plain object. */ declare function isPlainObject(obj: any): obj is object; /** * These are private action types reserved by Redux. * For any unknown actions, you must return the current state. * If the current state is undefined, you must return the initial state. * Do not reference these action types directly in your code. */ declare const ActionTypes: { INIT: string; REPLACE: string; PROBE_UNKNOWN_ACTION: () => string; }; export { Action, ActionCreator, ActionCreatorsMapObject, ActionFromReducer, ActionFromReducersMapObject, AnyAction, Dispatch, Middleware, MiddlewareAPI, Observable, Observer, PreloadedStateShapeFromReducersMapObject, Reducer, ReducerFromReducersMapObject, ReducersMapObject, StateFromReducersMapObject, Store, StoreCreator, StoreEnhancer, StoreEnhancerStoreCreator, UnknownAction, Unsubscribe, ActionTypes as __DO_NOT_USE__ActionTypes, applyMiddleware, bindActionCreators, combineReducers, compose, createStore, isAction, isPlainObject, legacy_createStore };