# HG changeset patch
# User deba
# Date 1176995579 0
# Node ID 08b64ae5a564e5d648a8a6be8e3b58692a4a8e12
# Parent  95cd24940d00b397b18217d608cc98abc110fd98
Helper classs for checking existence of a nested class

diff -r 95cd24940d00 -r 08b64ae5a564 lemon/bits/utility.h
--- a/lemon/bits/utility.h	Thu Apr 19 15:11:58 2007 +0000
+++ b/lemon/bits/utility.h	Thu Apr 19 15:12:59 2007 +0000
@@ -83,6 +83,12 @@
   template<int T> struct dummy { dummy(int) {} };
 
   /**************** enable_if from BOOST ****************/
+  
+  template <typename Type, typename T = void>
+  struct exists {
+    typedef T type;
+  };
+
  
   template <bool B, class T = void>
   struct enable_if_c {