tetstpr.adb

procedure Teststpr is
   type Kind is (A, B, C, D);

   Lol : constant := 12;

   subtype Subkind is Kind
   with Static_Predicate => Subkind = A or else (Lol > 20 and then Subkind = D);
   -- WHAT THE ACTUAL FUCK

   type Rec (K : Kind) is record
      case K is
         when Subkind => O : Integer;
         when others => null;
      end case;
   end record;

   R : Rec := (K => D, O => 12);
   -- Invalid because O is not a component of Rec
begin
   null;
end Teststpr;