How to narrow the type of a path param?

[rhuanbarreto]

In a route like this:

/$itemType/info

How can I assure that the type of itemType in useParams can be narrowed to an union of strings?

I already do the validation in the beforeLoad handler in $itemType.tsx:

beforeLoad: async ({ params: { itemType } }) => {
  if (!possibleTypes.find((n) => n === itemType))
    redirect({ to: "/not-found", throw: true });
}

[schiller-manuel]

this should do it https://tanstack.com/router/latest/docs/framework/react/api/router/RouteOptionsType#paramsparse-method

[rhuanbarreto]

And when does this run? Before or after beforeLoad?

[schiller-manuel]

before