diff --git a/source/ecs/manager.d b/source/ecs/manager.d
index 0d77132..2a34d27 100644
--- a/source/ecs/manager.d
+++ b/source/ecs/manager.d
@@ -514,19 +514,6 @@ class EntityManager
             return ret;
         }
 
-        string genParamsChecking()()
-        {
-            string ret;
-            foreach (func; __traits(getOverloads, Sys, "onUpdate"))
-            {
-                if ((Parameters!(func)).length == 1)
-                    ret ~= "\"" ~ (fullyQualifiedName!(Sys.EntitiesData)) ~ "\" == \"" ~ (
-                            fullyQualifiedName!((Parameters!(func))[0])) ~ "\" || ";
-            }
-            ret ~= "false";
-            return ret;
-        }
-
         static string genFillInputData()()
         {
             string ret;
@@ -596,8 +583,22 @@ class EntityManager
         {
             mixin(genFillInputData());
         }
+        
+        bool checkOnUpdateParams()()
+        {
+            bool ret = false;
+            foreach (func; __traits(getOverloads, Sys, "onUpdate"))
+            {
+                if ((Parameters!(func)).length == 1 && is(Parameters!(func)[0] == Sys.EntitiesData))
+                {
+                    ret = true;
+                    break;
+                }
+            }
+            return ret;
+        }
 
-        static if (hasMember!(Sys, "onUpdate") && (mixin(genParamsChecking())))
+        static if (hasMember!(Sys, "onUpdate") && checkOnUpdateParams())
         {
             static void callUpdate(ref CallData data)
             {
diff --git a/tests/tests.d b/tests/tests.d
index 50c31b6..60fed07 100644
--- a/tests/tests.d
+++ b/tests/tests.d
@@ -329,7 +329,7 @@ struct Sys3
 
 	void onUpdate(EntitiesData data)
 	{
-
+		
 	}
 }