Return type of debounced function not preserved

[todor-a]

TanStack Pacer version

0.2.0

Framework/Library version

React 19

Describe the bug and the steps to reproduce it

import { debounce } from '@tanstack/react-pacer';
import debounceLodash from 'lodash.debounce';

const withTanstack = debounce(
    () => 1,
    { wait: 500 }
);

const withLodash = debounceLodash(
    () => 2,
    500
);

withTanstack;
// ^? const withTanstack: () => void

withLodash;
// ^ const withLodash: DebouncedFunc<() => number>

Is this intentional?

Playground.

Your Minimal, Reproducible Example - (Sandbox Highly Recommended)

https://www.typescriptlang.org/play/?#code/JYWwDg9gTgLgBAbzgEwKYCMIFcB2BjVOAXzgDMoIQ4ByAARgEMcBnRvAawHopUG8YAtGD6oo1ANwAoUJFgoM2fKgAyEZA2YALMhSrUANmo2aAdGky4CEyZLwQW8AO7AYmgCpNWfdnAC88iyUACkk4MLgggEo-AD5EUPDEnhgsKBw4AEYpRKIAGgSwpEcGFwAuOABWAAYq4klIqVt7VjhnV1V1LT8AxQIO4xDEqNj4xKTUFLS4ACZs8LyCypr6xrb3TzZ2KU5OOAA9AH4bNf6tbd29oA

Screenshots or Videos (Optional)

No response

Do you intend to try to help solve this bug with your own PR?

yes

Terms & Code of Conduct

• I agree to follow this project's Code of Conduct
• I understand that if my bug cannot be reliable reproduced in a debuggable environment, it will probably not be fixed and this issue may even be closed.

[KevinVandy]

The next version is going to have better TFn generic patterns that fixes this. Thanks for the issue.

[KevinVandy]

Correction: Only the "Async" versions of each utility will be able to return a useful result for now. The normal debounce function will still have a void return type, as there are no promises under the hood there. This will just be one of the pros and cons of using async vs non-async versions. I could be convinced otherwise, but there seemed to be too many gotchas, or at least frustrating behavior with return previous results from the sync debounce or throttle utilities

[todor-a]

Thanks!

Btw, why are there two separate versions for async and not async?

[KevinVandy]

Btw, why are there two separate versions for async and not async?

They just have different use-cases, and can have a different API surface. In lots of situations where awaiting the promise is not needed, it both simplifies the API and the usage a lot. Our higher-level hooks like useDebouncedValue, createDebouncedSignal, etc. only need the sync versions.

[todor-a]

Thanks!