diff -r 53c2a0ccc9a4 -r afaa773d0ad0 src/lemon/utility.h
--- a/src/lemon/utility.h	Sat May 14 17:29:28 2005 +0000
+++ b/src/lemon/utility.h	Sat May 14 17:32:11 2005 +0000
@@ -107,6 +107,47 @@
   template <class Cond, class T> 
   struct lazy_disable_if : public lazy_disable_if_c<Cond::value, T> {};
 
+  // smart referencing
+
+  template <typename _Type, typename Enable = void>
+  struct SmartReference {
+    typedef _Type& Type;
+  };
+  
+  template <typename _Type>
+  struct SmartReference<
+    _Type, 
+    typename enable_if<typename _Type::NeedCopy, void>::type
+  > {
+    typedef _Type Type;
+  };
+
+  template <typename _Type, typename Enable = void>
+  struct SmartConstReference {
+    typedef const _Type& Type;
+  };
+  
+  template <typename _Type>
+  struct SmartConstReference<
+    _Type, 
+    typename enable_if<typename _Type::NeedCopy, void>::type
+  > {
+    typedef const _Type Type;
+  };
+
+  template <typename _Type, typename Enable = void>
+  struct SmartParameter {
+    typedef _Type& Type;
+  };
+  
+  template <typename _Type>
+  struct SmartParameter<
+    _Type, 
+    typename enable_if<typename _Type::NeedCopy, void>::type
+  > {
+    typedef const _Type& Type;
+  };
+
 } // namespace lemon
 
 #endif