What is the best way to create a generic function parameter for a single property of an object?

I am trying to refactor a generic function into accepting parameters as a single object

function test<T>(a: string, b: T, c: number)

Instead, I want the function to receive an object like this:

function test(params: {a: string; b: T, c: number})

I understand that I can create a generic object type using TypeScript

type MyObject<T> = {a: string; b: T, c: number}

However, I am struggling with how to handle the generic parameter when using this type as a function parameter

function test(params: MyObject<T>) // Where should I define T?

I have attempted to destructure the params type to specify the generic parameter, but it did not work as expected

function test<{_, T, __}>(params: MyObject<T>) // This approach did not achieve the intended result

Any advice or suggestions would be greatly appreciated. Thank you.

Answer №1

You're almost at the finish line, just remember to combine the general syntax in the function definition (<T>) with the parameter list. The only thing that changes is the b property, so using {a: string; b: T, c: number} will suffice - using string and number for the other properties is perfectly fine.

function exam<T>(params: {a: string; b: T, c: number}) {
    
}

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