public virtual void VisitMultipleTypeRef(BoundMultipleTypeRef x)
        {
            Debug.Assert(x != null);
            Debug.Assert(x.TypeExpression == null);
            Debug.Assert(x.BoundTypes.Length > 1);

            for (int i = 0; i < x.BoundTypes.Length; i++)
            {
                x.BoundTypes[i].Accept(this);
            }
        }
 public virtual TResult VisitMultipleTypeRef(BoundMultipleTypeRef x) => DefaultVisitOperation(x);
 public virtual TResult VisitMultipleTypeRef(BoundMultipleTypeRef x) => DefaultVisitType(x);