is expression for template structs/classes instances?

[d coder]

Greetings

I want to find if a given struct type is instantiated from a
particular template struct type. For example:

struct S (T)  {
  alias T Type;
  T t;
}

And later I want to find out if a given type is of type S(*)
(basically any type instantiated from template struct S). In fact I do
not know the type value T used at the time of instantiating S!(T).

I was looking at "is ( Type Identifier : TypeSpecialization ,
TemplateParameterList )" expression at
http://www.digitalmars.com/d/2.0/expression.html#IsExpression .
Thought there would be some way using that, but I could not find any.

Regards
Cherry