diff --git a/ZCppMain/ZMainHead.H b/ZCppMain/ZMainHead.H
index cb7266b..e48a57e 100644
--- a/ZCppMain/ZMainHead.H
+++ b/ZCppMain/ZMainHead.H
@@ -3261,6 +3261,89 @@ namespace ZNsMain
 
 
 
+    /*###################################################################
+
+    ■  template<typename TDataChain, int TInIndexNo> class ZtCTypeByNo
+
+        ZtCTypeChain, ZtCObjtChain 등을 template 인자로 받아, 어떤 index
+        숫자로부터 type 을 알 수 있게 한다. index 는 0 부터 시작한다.
+
+        이러면 ZtCObjtChain 의 활용성이 점점 높어지는 것이다. -- 2025-10-23 19:47
+
+    ■  예제 -- 2025-10-23 19:55
+
+        typedef ZtCObjtChain
+        <
+            char  , ZtCObjtChain<
+            string, ZtCObjtChain<
+            double, ZtCObjtChain<
+            int   ,
+            ZCEmpty > > >
+        > ZCObjtChain;  ZCObjtChain VO_ZCObjtChain;
+
+        VO_ZCObjtChain.GetChainNext().GetData()="abc";
+        *VO_ZCObjtChain       ='Z'      ;
+        *VO_ZCObjtChain()     ="New Str";
+        *VO_ZCObjtChain()()   =0.8      ;
+        *VO_ZCObjtChain()()() =1234     ;
+        VO_ZCObjtChain.IterHead(VO_ZCTypeView);
+
+        typedef ZtCTypeByNo<ZCObjtChain, 0>::TypeData  TypeDataHere0 ;
+        typedef ZtCTypeByNo<ZCObjtChain, 1>::TypeData  TypeDataHere1 ;
+        typedef ZtCTypeByNo<ZCObjtChain, 2>::TypeData  TypeDataHere2 ;
+        typedef ZtCTypeByNo<ZCObjtChain, 3>::TypeData  TypeDataHere3 ;
+        typedef ZtCTypeByNo<ZCObjtChain, 4>::TypeData  TypeDataHere4 ;
+
+        typedef ZtCTypeByNo<ZCObjtChain, 0>::TypeChain TypeChainHere0;
+        typedef ZtCTypeByNo<ZCObjtChain, 1>::TypeChain TypeChainHere1;
+        typedef ZtCTypeByNo<ZCObjtChain, 2>::TypeChain TypeChainHere2;
+        typedef ZtCTypeByNo<ZCObjtChain, 3>::TypeChain TypeChainHere3;
+        typedef ZtCTypeByNo<ZCObjtChain, 4>::TypeChain TypeChainHere4;
+
+        cout<<"# TypeDataHere0 ="<<typeid(TypeDataHere0 ).name()<<endl;
+        cout<<"# TypeDataHere1 ="<<typeid(TypeDataHere1 ).name()<<endl;
+        cout<<"# TypeDataHere2 ="<<typeid(TypeDataHere2 ).name()<<endl;
+        cout<<"# TypeDataHere3 ="<<typeid(TypeDataHere3 ).name()<<endl;
+        cout<<"# TypeDataHere4 ="<<typeid(TypeDataHere4 ).name()<<endl;
+
+        cout<<"# TypeChainHere0="<<typeid(TypeChainHere0).name()<<endl;
+        cout<<"# TypeChainHere1="<<typeid(TypeChainHere1).name()<<endl;
+        cout<<"# TypeChainHere2="<<typeid(TypeChainHere2).name()<<endl;
+        cout<<"# TypeChainHere3="<<typeid(TypeChainHere3).name()<<endl;
+        cout<<"# TypeChainHere4="<<typeid(TypeChainHere4).name()<<endl;
+
+    ###################################################################*/
+
+    template<typename TDataChain, int TInIndexNo> class ZtCTypeByNo
+    {
+    public:
+        typedef ZtCTypeByNo /*++++++++++++++++++++++++++++++++*/
+            <
+                typename TDataChain::TypeChainNext, TInIndexNo-1
+            >
+        ZCTypeByNoNext ; /*+++++++++++++++++++++++++++++++++++*/
+
+        typedef typename ZCTypeByNoNext::TypeData     TypeData  ;
+        typedef typename ZCTypeByNoNext::TypeDataC    TypeDataC ;
+        typedef typename ZCTypeByNoNext::TypeChain    TypeChain ;
+        typedef typename ZCTypeByNoNext::TypeChainC   TypeChainC;
+    public:
+    };/*
+    :::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::*/
+
+    template<typename TDataChain> class ZtCTypeByNo<TDataChain, 0>
+    {
+    public:
+        typedef /*----*/ TDataChain  /*----*/  TypeChain ;
+        typedef const    TDataChain  /*----*/  TypeChainC;
+        typedef typename TDataChain::TypeData  TypeData  ;
+        typedef typename TDataChain::TypeDataC TypeDataC ;
+    public:
+    };/*
+    :::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::*/
+
+
+
     template<   typename TDataNow, typename TTypeNextChain
             >
     class ZtCTypeChain ///////////////////////////////////
@@ -3650,6 +3733,26 @@ namespace ZNsMain
 
           -- 2025-10-22 19:41
 
+          ZtCTypeByNo 를 만들고 ZtCObjtChain 에 아래 멤버도 추가하고
+
+              template<int TInTypeNo> typename ZtCTypeByNo
+                  <TypeChainNow, TInTypeNo>::TypeChain & GetChainByNo()
+              template<int TInTypeNo> typename ZtCTypeByNo
+                  <TypeChainNow, TInTypeNo>::TypeChain & GetChainByNo() const
+
+          아래 예제 코드를 추가.
+
+              *VO_ZCObjtChain.GetChainByNo<0>()=('E');
+              *VO_ZCObjtChain.GetChainByNo<1>()=(string("New4 Str"));
+              *VO_ZCObjtChain.GetChainByNo<2>()=(1.8);
+              *VO_ZCObjtChain.GetChainByNo<3>()=(9999);
+              VO_ZCObjtChain.IterHead(ZftMCP(VO_ZCTypeView));
+              cout<<"************************************"<<endl;
+
+            보라! 각 객체에 깔끔하게 접근하고 있지 않는가... 고마운지고!!
+
+            -- 2025-10-24 09:09
+
     ■  ZtCObjtChain<TDataNow, ZCEmpty>::TypeChainLast 을 추가해,
 
            마지막 TypeChainNext 즉 마지막 TypeChainNow
@@ -3734,6 +3837,13 @@ namespace ZNsMain
         VO_ZCObjtChain.IterHead(ZftMCP(VO_ZCTypeView));
         cout<<"************************************"<<endl;
 
+        *VO_ZCObjtChain.GetChainByNo<0>()=('E');
+        *VO_ZCObjtChain.GetChainByNo<1>()=(string("New4 Str"));
+        *VO_ZCObjtChain.GetChainByNo<2>()=(1.8);
+        *VO_ZCObjtChain.GetChainByNo<3>()=(9999);
+        VO_ZCObjtChain.IterHead(ZftMCP(VO_ZCTypeView));
+        cout<<"************************************"<<endl;
+
     ///////////////////////////////////////////////////////////////////*/
 
     template /*########################################################*/
@@ -3772,14 +3882,14 @@ namespace ZNsMain
         TypeDataC& operator* () const{return mo_TypeVar;}
     /************************************************************/
         TypeChainNext & GetChainNext()
-            { return static_cast<TypeChainNext&>(*this); }
+            { return static_cast<TypeChainNext &>(*this); }
         TypeChainNextC& GetChainNext() const
-            { return static_cast<TypeChainNext&>(*this); }
+            { return static_cast<TypeChainNextC&>(*this); }
 
         TypeChainNext & operator()  ()
-            { return static_cast<TypeChainNext&>(*this); }
+            { return static_cast<TypeChainNext &>(*this); }
         TypeChainNextC& operator()  () const
-            { return static_cast<TypeChainNext&>(*this); }
+            { return static_cast<TypeChainNextC&>(*this); }
 
         template<typename TDataHere>
         TypeChainNow  & operator=  (const TDataHere& AR_Data)
@@ -3787,7 +3897,25 @@ namespace ZNsMain
         TypeChainNow  & operator=  (const TypeData & AR_Data)
             { mo_TypeVar=AR_Data; return *this;}
 
-    /************************************************************/
+    /**************************************************************/
+
+        template<int TInTypeNo> typename ZtCTypeByNo
+            <TypeChainNow, TInTypeNo>::TypeChain & GetChainByNo()
+        {
+            typedef typename ZtCTypeByNo
+                <TypeChainNow, TInTypeNo>::TypeChain  TypeChain ;
+
+            return *static_cast<TypeChain *>(this);
+        }
+        template<int TInTypeNo> typename ZtCTypeByNo
+            <TypeChainNow, TInTypeNo>::TypeChainC& GetChainByNo() const
+        {
+            typedef typename ZtCTypeByNo
+                <TypeChainNow, TInTypeNo>::TypeChainC TypeChainC;
+
+            return *static_cast<TypeChainC*>(this);
+        }
+        /*:::::::::::::::::::::::::::::::::::::::::::::::::::::::::::*/
 
         template<int TTypNo, typename TDataHere>
             bool SetDataRecur(const TDataHere& AR_Data)
@@ -3937,6 +4065,20 @@ namespace ZNsMain
             { mo_TypeVar=AR_Data; return *this;}
     /************************************************************/
 
+        template<int TInTypeNo> typename ZtCTypeByNo
+            <TypeChainNow, TInTypeNo>::TypeChain & GetChainByNo()
+        {
+            return *(this);
+        }
+        template<int TInTypeNo> typename ZtCTypeByNo
+            <TypeChainNow, TInTypeNo>::TypeChainC& GetChainByNo() const
+        {
+            return *(this);
+        }/*
+        template<int TInTypeNo> typename ZtCTypeByNo
+            <TypeChainNow, TInTypeNo>::TypeChainC& GetChainByNo() const
+        */
+
         template<int TTypNo, typename TDataHere>
             bool SetDataRecur(const TDataHere& AR_Data)
         {
@@ -3993,83 +4135,27 @@ namespace ZNsMain
     class ZtCObjtChain<TDataNow, ZCEmpty> /////////////////////////////*/
 
 
-
-    /*###################################################################
-
-    ■  template<typename TDataChain, int TInIndexNo> class ZtCTypeByNo
-
-        ZtCTypeChain, ZtCObjtChain 등을 template 인자로 받아, 어떤 index
-        숫자로부터 type 을 알 수 있게 한다. index 는 0 부터 시작한다.
-
-        이러면 ZtCObjtChain 의 활용성이 점점 높어지는 것이다. -- 2025-10-23 19:47
-
-    ■  예제 -- 2025-10-23 19:55
+    template<typename TDataNow, typename TTypeNextChain> std::ostream& operator<<
+        (
+            std::ostream& AR_COStream, const ZtCObjtChain
+                <TDataNow, TTypeNextChain>& AR_CChain
+        )
+    /*:::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::*/
+    {
+        AR_COStream<<AR_CChain.GetData();
 
         typedef ZtCObjtChain
-        <
-            char  , ZtCObjtChain<
-            string, ZtCObjtChain<
-            double, ZtCObjtChain<
-            int   ,
-            ZCEmpty > > >
-        > ZCObjtChain;  ZCObjtChain VO_ZCObjtChain;
+            <TDataNow, TTypeNextChain> TypeObjtChain;
 
-        VO_ZCObjtChain.GetChainNext().GetData()="abc";
-        *VO_ZCObjtChain       ='Z'      ;
-        *VO_ZCObjtChain()     ="New Str";
-        *VO_ZCObjtChain()()   =0.8      ;
-        *VO_ZCObjtChain()()() =1234     ;
-        VO_ZCObjtChain.IterHead(VO_ZCTypeView);
+        if(TypeObjtChain::ZEBoolNext>0)
+        {
+            cout<<", ";   return AR_COStream<<AR_CChain.GetChainNext() ;
+        }/*
+        if(TypeObjtChain::ZEBoolNext>0)*/
 
-        typedef ZtCTypeByNo<ZCObjtChain, 0>::TypeData  TypeDataHere0 ;
-        typedef ZtCTypeByNo<ZCObjtChain, 1>::TypeData  TypeDataHere1 ;
-        typedef ZtCTypeByNo<ZCObjtChain, 2>::TypeData  TypeDataHere2 ;
-        typedef ZtCTypeByNo<ZCObjtChain, 3>::TypeData  TypeDataHere3 ;
-        typedef ZtCTypeByNo<ZCObjtChain, 4>::TypeData  TypeDataHere4 ;
-
-        typedef ZtCTypeByNo<ZCObjtChain, 0>::TypeChain TypeChainHere0;
-        typedef ZtCTypeByNo<ZCObjtChain, 1>::TypeChain TypeChainHere1;
-        typedef ZtCTypeByNo<ZCObjtChain, 2>::TypeChain TypeChainHere2;
-        typedef ZtCTypeByNo<ZCObjtChain, 3>::TypeChain TypeChainHere3;
-        typedef ZtCTypeByNo<ZCObjtChain, 4>::TypeChain TypeChainHere4;
-
-        cout<<"# TypeDataHere0 ="<<typeid(TypeDataHere0 ).name()<<endl;
-        cout<<"# TypeDataHere1 ="<<typeid(TypeDataHere1 ).name()<<endl;
-        cout<<"# TypeDataHere2 ="<<typeid(TypeDataHere2 ).name()<<endl;
-        cout<<"# TypeDataHere3 ="<<typeid(TypeDataHere3 ).name()<<endl;
-        cout<<"# TypeDataHere4 ="<<typeid(TypeDataHere4 ).name()<<endl;
-
-        cout<<"# TypeChainHere0="<<typeid(TypeChainHere0).name()<<endl;
-        cout<<"# TypeChainHere1="<<typeid(TypeChainHere1).name()<<endl;
-        cout<<"# TypeChainHere2="<<typeid(TypeChainHere2).name()<<endl;
-        cout<<"# TypeChainHere3="<<typeid(TypeChainHere3).name()<<endl;
-        cout<<"# TypeChainHere4="<<typeid(TypeChainHere4).name()<<endl;
-
-    ###################################################################*/
-
-    template<typename TDataChain, int TInIndexNo> class ZtCTypeByNo
-    {
-    public:
-        typedef ZtCTypeByNo /*++++++++++++++++++++++++++++++++*/
-            <
-                typename TDataChain::TypeChainNext, TInIndexNo-1
-            >
-        ZCTypeByNoNext ; /*+++++++++++++++++++++++++++++++++++*/
-
-        typedef typename ZCTypeByNoNext::TypeData     TypeData ;
-        typedef typename ZCTypeByNoNext::TypeChain    TypeChain;
-    public:
-    };/*
-    :::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::*/
-
-    template<typename TDataChain> class ZtCTypeByNo<TDataChain, 0>
-    {
-    public:
-        typedef /*----*/ TDataChain  /*----*/ TypeChain;
-        typedef typename TDataChain::TypeData TypeData ;
-    public:
-    };/*
-    :::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::*/
+        return AR_COStream;
+    }
+    /*:::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::*/
 
 
 
diff --git a/ZCppMainTest/c++_test_006.cpp b/ZCppMainTest/c++_test_006.cpp
index d5d0fae..ea1fef1 100644
--- a/ZCppMainTest/c++_test_006.cpp
+++ b/ZCppMainTest/c++_test_006.cpp
@@ -215,10 +215,18 @@ namespace ZNsMain
             VO_ZCObjtChain.SetDataRecur<4>('D');
             VO_ZCObjtChain.SetDataRecur<3>(string("New3 Str"));
             VO_ZCObjtChain.SetDataRecur<2>(0.8);
-            VO_ZCObjtChain.SetDataRecur<1>(9999);
+            VO_ZCObjtChain.SetDataRecur<1>(9990);
             VO_ZCObjtChain.IterHead(ZftMCP(VO_ZCTypeView));
             cout<<"************************************"<<endl;
 
+            *VO_ZCObjtChain.GetChainByNo<0>()=('E');
+            *VO_ZCObjtChain.GetChainByNo<1>()=(string("New4 Str"));
+            *VO_ZCObjtChain.GetChainByNo<2>()=(1.8);
+            *VO_ZCObjtChain.GetChainByNo<3>()=(9999);
+            VO_ZCObjtChain.IterHead(ZftMCP(VO_ZCTypeView));
+            cout<<"#VO_ZCObjtChain = "<<VO_ZCObjtChain<<endl;
+            cout<<"************************************"<<endl;
+
 
             typedef ZtCTypeByNo<ZCObjtChain, 0>::TypeData  TypeDataHere0 ;
             typedef ZtCTypeByNo<ZCObjtChain, 1>::TypeData  TypeDataHere1 ;