diff --git a/include/onnxruntime/core/framework/data_types_internal.h b/include/onnxruntime/core/framework/data_types_internal.h
index 7dfd5da467..23e4166e20 100644
--- a/include/onnxruntime/core/framework/data_types_internal.h
+++ b/include/onnxruntime/core/framework/data_types_internal.h
@@ -224,10 +224,11 @@ inline bool IsPrimitiveDataType(const PrimitiveDataTypeBase* prim_type) {
 // GCC until very recently does not support template parameter pack expansion within lambda context.
 namespace mltype_dispatcher_internal {
 // T - type handled by this helper
-struct CallableDispatchableHelper {
+class CallableDispatchableHelper {
   int32_t dt_type_;  // Type currently dispatched
   size_t called_;
 
+ public:
   explicit CallableDispatchableHelper(int32_t dt_type) noexcept : dt_type_(dt_type), called_(0) {}
 
   // Must return integer to be in a expandable context
@@ -239,6 +240,11 @@ struct CallableDispatchableHelper {
     }
     return 0;
   }
+
+  void CheckCalledOnce() {
+    ORT_ENFORCE(called_ < 2, "Check for duplicate types in MLTypeCallDispatcher");
+    ORT_ENFORCE(called_ == 1, "Unsupported data type: ", dt_type_);
+  }
 };
 
 // Default policy is to throw with no return type.
@@ -251,11 +257,12 @@ struct UnsupportedTypeDefaultPolicy {
 
 // Helper with the result type
 template <class Ret, class UnsupportedPolicy = UnsupportedTypeDefaultPolicy<Ret>>
-struct CallableDispatchableRetHelper {
+class CallableDispatchableRetHelper {
   int32_t dt_type_;  // Type currently dispatched
   size_t called_;
   Ret result_;
 
+ public:
   explicit CallableDispatchableRetHelper(int32_t dt_type) noexcept : dt_type_(dt_type), called_(0), result_() {}
 
   Ret Get() {
@@ -312,8 +319,7 @@ class MLTypeCallDispatcher {
     mltype_dispatcher_internal::CallableDispatchableHelper helper(dt_type_);
     int results[] = {0, helper.template Invoke<Types>(Fn<Types>(), std::forward<Args>(args)...)...};
     ORT_UNUSED_PARAMETER(results);
-    ORT_ENFORCE(helper.called_ < 2, "Check for duplicate types in MLTypeCallDispatcher");
-    ORT_ENFORCE(helper.called_ == 1, "Unsupported data type: ", dt_type_);
+    helper.CheckCalledOnce();
   }
 };
 
@@ -370,7 +376,7 @@ class MLTypeCallDispatcher2 {
     // avoid "unused parameter" warning for the case where Types is empty
     static_cast<void>(std::array<int, sizeof...(Args)>{(ORT_UNUSED_PARAMETER(args), 0)...});
 
-    ORT_ENFORCE(helper.called_ == 1, "Unsupported data type: ", dt_type_);
+    helper.CheckCalledOnce();
   }
 
   template <template <typename...> class Fn, typename LeadingTemplateArgTypeList, typename... Args>
@@ -385,7 +391,7 @@ class MLTypeCallDispatcher2 {
     // avoid "unused parameter" warning for the case where Types is empty
     static_cast<void>(std::array<int, sizeof...(Args)>{(ORT_UNUSED_PARAMETER(args), 0)...});
 
-    ORT_ENFORCE(helper.called_ == 1, "Unsupported data type: ", dt_type_);
+    helper.CheckCalledOnce();
   }
 };