Defining the type of the createAction() function in TypeScript within the context of Redux Toolkit

Lately, I have been delving into the redux-toolkit library but I am struggling with understanding the type declaration of the createAction function as demonstrated below.


The createAction function returns a PayloadActionCreator which includes a generic of 

<ReturnType<PA>['payload'], T, PA>
. Could someone explain what is meant by ReturnType<PA>['payload']?

export declare function createAction<PA extends PrepareAction<any>, T extends string = string>(type: T, prepareAction: PA): PayloadActionCreator<ReturnType<PA>['payload'], T, PA>
typescriptgenericsreduxredux-toolkit

Answer №1

ReturnType<PA>['payload'] represents the payload attribute of the object that is given back by the prepare function - following the format specified for the prepare notation.

Nevertheless, you don't need to worry about this too much. Typically, you would use it like so: 

const actionCreator = createAction<PayloadType>('some/action/type')
.

An alternate way to write this is using the prepare notation, as shown here: 

createAction('some/action/type', (payload: string) => ({ payload, meta: {something: "foo"}})
.

For more details and examples in TypeScript, please visit the API documentation, which covers most scenarios. It's recommended not to overcomplicate the typings beyond what's necessary. (And yes, there aren't many types to handle, which is intentional ;) )

Similar questions

If you have not found the answer to your question or you are interested in this topic, then look at other similar questions below or use the search

Callback for dispatching a union type

I am currently in the process of developing a versatile function that will be used for creating callback actions. However, I am facing some uncertainty on how to handle union types in this particular scenario. The function is designed to take a type as inp ...

typescriptreduxtypescript-generics

Trouble arises when attempting to import React JSX project/modules from npm into an AngularJS TypeScript module

In the process of developing a proof-of-concept React framework/library, I aim to create a versatile solution that can be utilized in both React and AngularJS applications. To achieve this goal, I have initiated two separate projects: - sample-react-frame ...

angularjstypescriptnpmwebpackreactjs

The error message states that the property "user" is not found in the type "Session & Partial<SessionData>"

I recently had a javascript code that I'm now attempting to convert into typescript route.get('/order', async(req,res) => { var sessionData = req.session; if(typeof sessionData.user === 'undefined') { ...

javascriptnode.jstypescriptexpresssession

Guide to building an interface for an object containing a nested array

While working on my Angular/TypeScript project, I encountered a challenge in processing a GET request to retrieve objects from an integration account. Here is a snippet of the response data: { "value": [ { "properties": { ...

angulartypescript

Filtering nested arrays in Javascript involves iterating through each nested

I have a nested array inside an array of objects in my Angular app that I'm attempting to filter. Here is a snippet of the component code: var teams = [ { name: 'Team1', members: [{ name: 'm1' }, { name: 'm2' }, { name ...

javascriptangulartypescript

What causes React component state initialization to return a `never` type when set to null?

Initializing a component's state to null outside of the constructor results in the state having the type never in the render function. However, when the state is initialized within the constructor, the correct type is maintained. Despite many StackO ...

reactjstypescript

NativeScript: TypeScript for Formatting Numbers

Being a beginner in NativeScript, I'm finding it difficult to find basic information through Google search. But now, I have a specific question: I have the number 1234567.89 stored in a variable, and I want to display it in a label with the format ...

typescriptnativescript

Component unit testing in Angular 2/4 fails to register click events causing a lack of change detection

I'm currently working on testing a component in Angular 2/4 to determine if clicking on a button element will result in the desired changes. However, I'm facing an issue with triggering the click event. Here is the component code: import { Comp ...

angularunit-testingtypescript

Is it possible to dynamically check values in TypeScript?

[Summary] I am looking to dynamically expand my type in TypeScript based on an initial set of values. I want to avoid managing separate arrays/types and instead extend all strings in my type with '_max'. type ExtendedValueTypes = 'money&apos ...

typescripttype-declaration

Creating Dynamic Forms in React with Typescript: A Step-by-Step Guide to Adding Form Elements with an onClick Event Handler

I am looking to create a dynamic generation of TextFields and then store their values in an array within the state. Here are my imports: import TextField from '@material-ui/core/TextField'; import Button from '@material-ui/core/Button&apos ...

reactjstypescriptmaterial-ui

Can you explain the significance of using square brackets in the typescript enum declaration?

While reviewing a typescript file within an Angular ngrx project titled collection.ts, I came across the declaration of enum constants. import { Action } from '@ngrx/store'; import { Book } from '../models/book'; export enum Collecti ...

angulartypescriptenumsngrxngrx-store

After upgrading Expo, the React Native Auth Session ceased to function

During my use of Expo SDK 48, my app successfully implemented Google and Facebook authentication with a web browser-based authentication method. Functional code: type AuthResponse = AuthSession.AuthSessionResult & { params: { access_token ...

typescriptreact-nativeoauth-2.0expoexpo-auth-session

Changing the ngModel value within ngFor loop

I am working on a project where I need to display a list of grades from an object called 'grades'. Additionally, I want to integrate a slider component for each grade, with the value of the slider corresponding to a predefined list. However, it s ...

angulartypescriptsliderangular-ngmodel

A comprehensive guide on enabling visibility of a variable within the confines of a function scope

In the code snippet shown below, I am facing an issue with accessing the variable AoC in the scope of the function VectorTileLayer. The variable is declared but not defined within that scope. How can I access the variable AoC within the scope of VectorTile ...

angulartypescriptopenlayersangular-openlayers

What allows the type expression to be considered valid with a reduced amount of arguments?

Currently diving into Typescript and focusing on functions in this unit. Check out the following code snippet: type FunctionTypeForArrMap = (value: number, index: number, arr: number[]) => number function map (arr: number[], cb: FunctionTypeForArr ...

typescriptfunctionparametersarguments

Axios is causing my Pokemon state elements to render in a jumbled order

Forgive me if this sounds like a silly question - I am currently working on a small Pokedex application using React and TypeScript. I'm facing an issue where after the initial page load, some items appear out of order after a few refreshes. This make ...

javascriptreactjstypescriptaxios

The form will not appear if there is no data bound to it

Can anyone help me with displaying the form even when the data is empty in my template? <form class="nobottommargin" *ngIf="details" [formGroup]="form" (ngSubmit)="onSubmit(form.value)" name="template-contactform"> <div class="col-sm-12 nopad ...

angulartypescript

Navigating JSON data with unexpected fields in Typescript and React.js

Looking to parse a JSON string with random fields in Typescript, without prior knowledge of the field types. I want to convert the JSON string into an object with default field types, such as strings. The current parsing method is: let values = JSON.parse ...

javascriptreactjstypescript

Is it possible to modify the number format of an input field while in Antd's table-row-edit mode?

I am currently utilizing the Table Component of Ant Design v2.x and unfortunately, I cannot conduct an upgrade. My concern lies with the inconsistent formatting of numbers in row-edit mode. In Display mode, I have German formatting (which is desired), but ...

reactjstypescriptantd

There seems to be an issue with the TypeScript error: it does not recognize the property on the options

I have an item that looks like this: let options = {title: "", buttons: undefined} However, I would like to include a function, such as the following: options.open() {...} TypeScript is giving an error message: property does not exist on the options ty ...

typescript