Index: const_iterator.hpp
===================================================================
--- const_iterator.hpp	(revision 50412)
+++ const_iterator.hpp	(working copy)
@@ -21,6 +21,7 @@
 #include <boost/range/detail/const_iterator.hpp>
 #else
 
+#include <boost/range/detail/extract_optional_type.hpp>
 #include <boost/type_traits/remove_const.hpp>
 #include <cstddef>
 #include <utility>
@@ -31,11 +32,13 @@
     // default
     //////////////////////////////////////////////////////////////////////////
     
-    template< typename C >
-    struct range_const_iterator
-    {
-        typedef BOOST_DEDUCED_TYPENAME C::const_iterator type;
-    };
+	namespace detail {
+		BOOST_EXTRACT_OPTIONAL_TYPE( const_iterator )
+	}
+
+	template< typename C >
+	struct range_const_iterator: detail::extract_const_iterator<C>
+	{};
     
     //////////////////////////////////////////////////////////////////////////
     // pair
Index: detail/extract_optional_type.hpp
===================================================================
--- detail/extract_optional_type.hpp	(revision 0)
+++ detail/extract_optional_type.hpp	(revision 0)
@@ -0,0 +1,29 @@
+#ifndef BOOST_EXTRACT_OPTIONAL_TYPE_HPP
+#define BOOST_EXTRACT_OPTIONAL_TYPE_HPP
+
+#if defined(_MSC_VER) && (_MSC_VER >= 1200)
+# pragma once
+#endif
+
+#include <boost/config.hpp>
+
+namespace boost {
+	namespace detail {
+		template< typename T > struct exists { typedef void type; };
+	}
+}
+
+// Defines extract_some_typedef<T> which exposes T::some_typedef as extract_some_typedef<T>::type
+// if T::some_typedef exists. Otherwise extract_some_typedef<T> is empty.
+#define BOOST_EXTRACT_OPTIONAL_TYPE( some_typedef )                                                    \
+	template< typename C, typename Enable=void >                                                       \
+	struct extract_ ## some_typedef                                                                    \
+	{};                                                                                                \
+	template< typename C >                                                                             \
+	struct extract_ ## some_typedef< C                                                                 \
+		, BOOST_DEDUCED_TYPENAME boost::detail::exists< BOOST_DEDUCED_TYPENAME C::some_typedef >::type \
+	> {                                                                                                \
+		typedef BOOST_DEDUCED_TYPENAME C::some_typedef type;                                           \
+	};
+
+#endif
\ No newline at end of file
Index: mutable_iterator.hpp
===================================================================
--- mutable_iterator.hpp	(revision 50412)
+++ mutable_iterator.hpp	(working copy)
@@ -21,6 +21,7 @@
 #include <boost/range/detail/iterator.hpp>
 #else
 
+#include <boost/range/detail/extract_optional_type.hpp>
 #include <boost/iterator/iterator_traits.hpp>
 #include <cstddef>
 #include <utility>
@@ -31,11 +32,13 @@
     // default
     //////////////////////////////////////////////////////////////////////////
     
-    template< typename C >
-    struct range_mutable_iterator
-    {
-        typedef BOOST_DEDUCED_TYPENAME C::iterator type;
-    };
+	namespace detail {
+		BOOST_EXTRACT_OPTIONAL_TYPE( iterator )
+	}
+
+	template< typename C >
+	struct range_mutable_iterator: detail::extract_iterator<C>
+	{};
     
     //////////////////////////////////////////////////////////////////////////
     // pair