I am trying to use something like the following to create routes for types that implement a trait:

trait HasPayload {
	type Payload: DeserializeOwned;
}

async fn handler_doesnt_work<T: HasPayload>(Json(payload): Json<T::Payload>) -> impl IntoResponse {
	/* ... */
}

async fn handler_works<T: HasPayload>() -> impl IntoResponse {
	/* ... */
}

fn router<T: HasPayload>() -> Router {
	Router::new()
		.route("/works", get(handler_works::<T>))
		.route("/doesnt_work", post(handler_doesnt_work::<T>))
}

However handler_doesnt_work doesn't satisfy the trait bounds. Why is this, and how can I fix or work around it? #[axum::debug_handler] says it doesn't support generic functions

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