[feature-request] Allow list of variants for route params

[xaota]

{
  path: "route/:param/:type?",
  Component,
  errorElement: <ErrorBoundary />
}

How i can describe variants for :param and :type?

I need show errorElement if param in my route not in variants array

Feature Request

{
  path: "route/:param/:type?",
  variants: {
    ":param": ["feature-a", "feature-b", "feature-c"],
    ":type": ["type-a", "type-b", "type-c"]
  },
  Component,
  errorElement: <ErrorBoundary />
}

And, if param not in variants[paramName] list -> return errorElement

[Bessonov]

+1. In an unreleased version of my (nodejs/server-side) router, I am using some sort of validator for this:

router.addRoute({
	matcher: endpoint('GET', /^\/user\/(?<userId>[^/]+)$/
		{
			url: {
				userId: chain(getNthVal(), requiredVal(), toNumVal()),
			},
			query: {
				// profile query parameter is optional in this example
				profile: chain(atLeastOneVal([undefined, 'short', 'full']), getNthVal()),
			},
		},
	),
	handler: ({ match: { result: { pathname, query } } }) => {
		return `User id: ${pathname.params.userId}, profile: ${query.profile}.`,
	}
})

They are more flexible than just variants.