public class B[T]
{
  public Add (mutable  _obj : T) :  int
  {
     -1;
  }

  public AddRange (mutable  o : object) :  void
  {
    mutable  obj = ( o :> T);
    _ = Add (obj);
  }
}

public interface IA
{
}

public class A : IA
{
}

public class Test
{
  public static Main () :  void
  {
    mutable  aux =  B ();
    aux.AddRange ( A ());
  }    
}
/*
BEGIN-OUTPUT
END-OUTPUT
*/