Index: boost/range/adaptor/map.hpp
===================================================================
--- boost/range/adaptor/map.hpp	(revision 66808)
+++ boost/range/adaptor/map.hpp	(working copy)
@@ -25,7 +25,7 @@
         template< class Map >
         struct select_first
         {
-            typedef BOOST_DEDUCED_TYPENAME range_value<Map>::type pair_t;
+            typedef BOOST_DEDUCED_TYPENAME range_value<const Map>::type pair_t;
             typedef const BOOST_DEDUCED_TYPENAME pair_t::first_type&
                 result_type;