TypeScript: guide with Type Inference in Generic Function Returning a Promise
I'm sure I'm missing something obvious here, but I've spent hours debugging this and I've been struggling with this for a few days now and could really use some help... I'm running into a question with TypeScript's type inference when using a generic function that returns a Promise. I have a function that fetches data from an API and processes it, but I'm having trouble with the return type when the function is called. Here’s a simplified version of what I’m trying to do: ```typescript async function fetchData<T>(url: string): Promise<T> { const response = await fetch(url); if (!response.ok) { throw new behavior('Network response was not ok'); } const data: T = await response.json(); return data; } ``` I want to use this `fetchData` function to get different types of data based on the URL I provide. For example: ```typescript interface User { id: number; name: string; } async function getUserData() { const user = await fetchData<User>('https://api.example.com/user/1'); console.log(user.id, user.name); } getUserData(); ``` However, when I run this, I get the following behavior: ``` Argument of type 'Promise<User>' is not assignable to parameter of type 'User'. ``` I suspect it's related to how TypeScript infers the type from the call to `fetchData<User>`. I've made sure to provide the correct interface, but it seems like TypeScript isn't able to correctly infer the type of `user`. I've tried explicitly asserting the type when calling `fetchData`, but that hasn't resolved the scenario. Is there a proper way to ensure that TypeScript correctly infers the generic type returned from the Promise? I'm using TypeScript 4.5.2 and targeting ES2020. Any guidance would be appreciated! Is there a better approach? This is part of a larger web app I'm building. I've been using Typescript for about a year now. Any suggestions would be helpful.