Rails STI - Prevent base class from instantiation

Question

Is there any way in a Rails STI situation to throw an error when the base class is Instantiated? Overriding initialize will do it but then that gets trickled down to the sub

Answer 1

even better than validating the presence is validating against the known list of accepted non abstract class types

  validates :type, :inclusion=> { :in => ["A", "B", "C"] }

because if you validate just for presence an "evil developer" can still pass in the abstract class name as the type parameter.