diff --git a/ndn-cpp/encoding/der/visitor/simple-visitor.cpp b/ndn-cpp/encoding/der/visitor/simple-visitor.cpp
index 7007505..8539950 100644
--- a/ndn-cpp/encoding/der/visitor/simple-visitor.cpp
+++ b/ndn-cpp/encoding/der/visitor/simple-visitor.cpp
@@ -6,6 +6,9 @@
  * See COPYING for copyright and distribution information.
  */
 
+#if 1 // TODO: Remove this when we don't throw "not implemented".
+#include <stdexcept>
+#endif
 #include "simple-visitor.hpp"
 #include "../der.hpp"
 #include <ndn-cpp/encoding/oid.hpp>
@@ -62,6 +65,7 @@
 ndnboost::any 
 SimpleVisitor::visit(DerOid& derOid)
 {
+#if 0 // Include again when der is defined.
   vector<int> intList;
   int offset = 0;
 
@@ -79,6 +83,9 @@
   }
   
   return ndnboost::any(OID(intList));
+#else
+  throw std::runtime_error("not implemented");
+#endif
 }
 
 ndnboost::any