Determine the type and create an instance of a fresh class

In my app, I have a function that handles all API requests. Any interaction I make goes through this function.

I'm trying to set a specific return type for this function, but the return type is of a class. In order to use the methods of this class, I need to instantiate it dynamically.

const sendRequest = async <T>(uri: string, options: any): Promise<T> => {
  // ... request logic here.

  const data = await response.json();

  return new T(data);
}

As expected, this approach didn't work. I'm wondering if there's a workaround or solution that would allow me to return a class instance when passing in the data?

Answer №1

If you define a parameter with a construct signature that returns T, you can then use it within the function body to instantiate an object of that "class".

const sendRequest = async <T>(uri: string, options: any, into: new (data: any) => T): Promise<T> => {
  // ... request logic goes here.

  const data = await response.json();

  return new into(data);
};

This approach also works with String or Number, but caution is advised! These will yield types String and Number, not string and number.

Interactive example

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

What is the best way to define types for an array of objects with interconnected properties?

I need to define a type for an object called root, which holds a nested array of objects called values. Each object in the array has properties named one (of any type) and all (an array of the same type as one). Below is my attempt at creating this type d ...

Ways to invoke a slice reducer from a library rather than a React component

I've been working on a React application using the React Boilerplate CRA Template as my foundation. This boilerplate utilizes Redux with slices, which is great for updating state within a React component. However, I'm facing a challenge when try ...

Specify the object key type when using a `for-in` loop

My current situation involves an object type: interface ShortUrlParam { openid: string; avatar: string; nickname: string; } const param: ShortUrlParam = { openid: 'abc123', avatar: '', nickname: 'wenzi&apo ...

Error message: Angular material StaticInjectorError - MatDialog provider not found

After trying to launch my Angular 5 page in the browser, I encountered an error message in the console. ERROR Error: StaticInjectorError(AppModule)[AppComponent -> MatDialog]: StaticInjectorError(Platform: core)[AppComponent -> MatDialog]: ...

Guide to building a nested React component

My custom dropdown component requires 2 props: trigger (to activate the dropdown) list (content to display in the dropdown) Below is the implementation of my component: import { useLayer } from "react-laag"; import { ReactElement, useState } fr ...

Working with e.charcode in TypeScript allows for easy access to

I'm having trouble understanding why this code snippet is not functioning as expected. const addRate = (e: { charCode: KeyboardEvent }) => { if (e.charCode >= 48) { ... } } The error message I receive states: 'Operator '>=& ...

Trouble with V-if not updating after property is modified within an async TypeScript function

There is a scenario where one HTML element becomes hidden after an async call returns from the server, while another HTML element is displayed: <template> <div v-if="!showElementTwo">Element 1</div> <div v-if="show ...

Exploring the @HostBinding argument in Angular directives

Need help grasping the concept behind the @Hostbinding argument: Snippet of the code: import { Directive, HostBinding } from "@angular/core"; @Directive({ selector: '[appDropdown]' }) export class DropdownDirective { @HostBinding(&apos ...

Issues with NPM start arise moments after incorporating create react app typescript into the project

I've encountered an error while trying to initiate my create react app with Typescript. Despite following all the necessary steps, including adding the .env file (with SKIP_PREFLIGHT_CHECK=true) and updating/reinstalling NPM, I keep facing this issue. ...

Declaring and accessing class variables in Angular 4

I am facing an issue with the following TypeScript model: export class User { email: string; token: string; username: string; bio: string; image: string; constructor() {} } When I attempt to instantiate this model in another TypeScript file, ...

Tips for utilizing playFromPositionAsync method with expo-av Video in React Native

While working with the Video Expo component, I came across a prop called playFromPositionAsync. In the Video.d.ts file, it is defined like this: export default class Video extends React.Component<VideoProps, VideoState> implements Playback { ... ...

Is it possible for an Interface's property to be a type that contains an array?

As I dive into the Angular code, I encountered a peculiar type for a property within an Interface named 'Origin' that has left me perplexed. Here's the snippet: export interface Origin { areaNum?: number; open?: { [key: stri ...

typescript - transforming text into numerical values

newbalance = (Number(this.balance)) + (Number(this.pastAmount)); The result for my newbalance calculation is coming back as undefined, even though this.balance is 34 and this.pastAmount is 23. I've set this up in the controller and I'm trying t ...

Submit a Post request with a file and JSON information included

I'm encountering an issue while trying to pass files with a JSON object. It seems like there might be an error in the controller where the 'consumes' and 'produces' declarations are possibly incorrect. I need assistance on how to a ...

"Troubleshooting the issue of Angular's ng-selected not functioning properly within an edit

https://i.stack.imgur.com/ZpCmx.png https://i.stack.imgur.com/h3TA6.png TS Pincodes: Array<string> = []; Html <ng-select [items]="Pincodes" [searchable]="true" [multiple]="true" [(ngModel)]="updateZoneDetails ...

Testing @microsoft/applicationinsights-web within an Angular project on a local environment

How can I test Microsoft's application insights locally? Most guides I've come across suggest testing it on the Azure portal, but I can't do that as it would mean testing it in a production environment. ...

Error encountered while fetching client credentials in Next-Auth Credential-Provider [next-auth]

Exploring the combination of nextjs and next-auth for authentication using a credential provider has been intriguing. However, I've encountered an issue when attempting to access a protected route while logged in: [next-auth][error][client_fetch_error ...

Unable to determine the data type of the JSON object during the

I'm having trouble reading an Object type of json... Here is the json I'm working with: body: { "111": { "name": "name1", "status": 10000 }, "222": { "name": "name2", "status": 20000 }, "333": ...

Creating a ref in React with TypeScript to access the state of a child component

Is there a way to access the state of a child component within the parent component without using handlers in the child or lifting the state up in the parent? How can I utilize refs in React with TypeScript to createRef and retrieve the child's state ...

Issue with Socket.io: Data not received by the last user who connected

I have developed a Node.js and Express application with real-time drawing functionality on canvas using socket.io version 1.7.2. Users are divided into separate socket rooms to enable multiple teams to draw independently. However, there is an issue where t ...