diff --git a/src/lib/diff/gen-node.hpp b/src/lib/diff/gen-node.hpp
index a821db633..09ad59421 100644
--- a/src/lib/diff/gen-node.hpp
+++ b/src/lib/diff/gen-node.hpp
@@ -101,6 +101,7 @@
 #include "lib/variant.hpp"
 #include "lib/time/timevalue.hpp"
 #include "lib/diff/record.hpp"
+#include "lib/idi/entry-id.hpp"
 //#include "lib/util.hpp"
 //#include "lib/format-string.hpp"
 
@@ -148,13 +149,88 @@ namespace diff{
       DataCap(X&& x)
         : Variant<DataValues>(std::forward<X>(x))
         { }
+      
+      DataCap(DataCap const& o) =default;
+      DataCap(DataCap&& o)      =default;
+      DataCap(DataCap& o)
+        : DataCap((DataCap const&)o)
+        { }
     };
   
   
   /** generic data element node within a tree */
-  class GenNode
+  struct GenNode
     {
-    public:
+      class ID
+        : public idi::BareEntryID
+        {
+          friend class GenNode;
+          
+          template<typename X>
+          ID (X*, string const& symbolicID)
+            : idi::BareEntryID (symbolicID,
+                                idi::getTypeHash<X>())
+            { }
+          
+        public:
+          ID (GenNode const& node)
+            : ID(node.idi)
+            { }
+          
+          // standard copy operations acceptable
+        };
+      
+      ID      idi;
+      DataCap data;
+      
+      template<typename X>
+      GenNode(X&& val)
+        : idi(&val, buildChildID<X>())
+        , data(std::forward<X>(val))
+        { }
+      
+      template<typename X>
+      GenNode(string const& symbolicID, X&& val)
+        : idi(&val, symbolicID)
+        , data(std::forward<X>(val))
+        { }
+      
+      GenNode(string const& symbolicID, const char* text)
+        : GenNode(symbolicID, string(text))
+        { }
+      
+      GenNode(const char* text)
+        : GenNode(string(text))
+        { }
+      
+      GenNode(GenNode const& o)  =default;
+      GenNode(GenNode&& o)       =default;
+      GenNode(GenNode& o)
+        : GenNode((GenNode const&)o)
+        { }
+      
+      // default copy assignable
+      
+      
+      bool
+      isNamed()  const
+        {
+          return util::startsWith (idi.getSym(), "_CHILD_");
+        }
+      
+      friend string
+      name (GenNode const& node)
+      {
+        return node.idi.getSym();
+      }
+      
+    private:
+      template<typename X>
+      static string
+      buildChildID()
+        {
+          return "_CHILD_" + idi::generateSymbolicID<X>();
+        }
     };
   
   
@@ -186,21 +262,21 @@ namespace diff{
   inline GenNode
   Rec::buildTypeAttribute (string const& typeID)
   {
-    return GenNode(); ///TODO
+    return GenNode("type", typeID);
   }
   
   template<>
   inline string
   Rec::extractKey (GenNode const& v)
   {
-    return "todo"; ////TODO
+    return v.idi.getSym();
   }
   
   template<>
   inline GenNode
   Rec::extractVal (GenNode const& v)
   {
-    return GenNode(); ///TODO
+    return GenNode(v); ///TODO
   }
   
   
diff --git a/src/lib/variant.hpp b/src/lib/variant.hpp
index 938fd2203..2ffb00143 100644
--- a/src/lib/variant.hpp
+++ b/src/lib/variant.hpp
@@ -111,6 +111,12 @@ namespace lib {
         using Type = X;
       };
     
+    template<typename X, typename TYPES>
+    struct CanBuildFrom<const X, Node<X, TYPES>>
+      {
+        using Type = X;
+      };
+    
     template<typename X, typename T,typename TYPES>
     struct CanBuildFrom<X, Node<T, TYPES>>
       {
diff --git a/tests/library/diff/gen-node-basic-test.cpp b/tests/library/diff/gen-node-basic-test.cpp
index 58ed90248..161b47854 100644
--- a/tests/library/diff/gen-node-basic-test.cpp
+++ b/tests/library/diff/gen-node-basic-test.cpp
@@ -33,7 +33,9 @@
 //#include <vector>
 #include <cmath>
 
+using util::isnil;
 using util::contains;
+using util::isSameObject;
 using lib::time::Time;
 using lib::time::TimeSpan;
 //using std::string;
@@ -93,7 +95,6 @@ namespace test{
           objectShortcut();
           symbolReference();
           sequenceIteration();
-          duplicateDetection();
           copy_and_move();
         }
       
@@ -110,7 +111,7 @@ namespace test{
           
           // can optionally be named
           GenNode n2("π", 3.14159265358979323846264338328);
-          CHECK (fabs (3.14159265 - n2.data.get<double>) < 1e-5 );
+          CHECK (fabs (3.14159265 - n2.data.get<double>()) < 1e-5 );
           CHECK (n2.isNamed());
           CHECK ("π" == n2.idi.getSym());
           CHECK ("π" == name(n2));
@@ -255,18 +256,14 @@ namespace test{
       void
       sequenceIteration()
         {
-        }
-      
-      
-      void
-      duplicateDetection()
-        {
+          UNIMPLEMENTED ("wtf");
         }
       
       
       void
       copy_and_move()
         {
+          UNIMPLEMENTED ("need to check that?");
         }
     };
   
diff --git a/wiki/thinkPad.ichthyo.mm b/wiki/thinkPad.ichthyo.mm
index d3566b380..8357203dc 100644
--- a/wiki/thinkPad.ichthyo.mm
+++ b/wiki/thinkPad.ichthyo.mm
@@ -35,7 +35,13 @@
 <node CREATED="1435421670349" ID="ID_1358247529" MODIFIED="1435421676200" TEXT="verwende EntryID">
 <node CREATED="1435421678004" ID="ID_691179282" MODIFIED="1435421687224" TEXT="Abh&#xe4;ngigkeitsprobleme">
 <node CREATED="1435421693260" ID="ID_1314021887" MODIFIED="1435421708857" TEXT="generische ID-Funktionen"/>
-<node CREATED="1435421739988" ID="ID_405602814" MODIFIED="1435421749352" TEXT="EntryID geh&#xf6;rt in Library"/>
+<node CREATED="1435421739988" ID="ID_405602814" MODIFIED="1435885199446" TEXT="EntryID geh&#xf6;rt in Library">
+<icon BUILTIN="button_ok"/>
+</node>
+</node>
+<node CREATED="1435885214592" ID="ID_1198930165" MODIFIED="1435885223858" TEXT="sanitise st&#xf6;rt">
+<node CREATED="1435885226222" ID="ID_776697956" MODIFIED="1435885235138" TEXT="verschiebe in EntryID"/>
+<node CREATED="1435885235583" ID="ID_444167455" MODIFIED="1435885247194" TEXT="verwende Subklasse"/>
 </node>
 </node>
 </node>