Dependent types to the rescue!

Unfortunately dependent types are incredibly difficult to get working (Scala's type system is already turing complete (and can handle path-dependent types) and true dependent types would make reasoning about nigh-on impossible).

I would argue that you're dealing with a sub-typing problem here, Email <: String, LongLat <: (Int, Int)*

* I would say in Scala:

  case class LongLat(longitude: Int, Latitude: Int)