[boost][range] - Added has_range_iterator and has_range_const_iterator. Trac ticket 4296.

[SVN r67433]

include/boost/range/has_range_iterator.hpp

@@ -0,0 +1,62 @@
+// Boost.Range library
+//
+//  Copyright Neil Groves 2010. Use, modification and
+//  distribution is subject to the Boost Software License, Version
+//  1.0. (See accompanying file LICENSE_1_0.txt or copy at
+//  http://www.boost.org/LICENSE_1_0.txt)
+//
+// For more information, see http://www.boost.org/libs/range/
+//
+#ifndef BOOST_RANGE_HAS_ITERATOR_HPP_INCLUDED
+#define BOOST_RANGE_HAS_ITERATOR_HPP_INCLUDED
+
+#include <boost/mpl/bool.hpp>
+#include <boost/mpl/has_xxx.hpp>
+#include <boost/range/iterator.hpp>
+#include <boost/utility.hpp>
+
+namespace boost
+{
+    namespace range_detail
+    {
+        BOOST_MPL_HAS_XXX_TRAIT_DEF(type);
+
+        template<class T, class Enabler = void>
+        struct has_range_iterator_impl
+            : boost::mpl::false_
+        {
+        };
+
+        template<class T>
+        struct has_range_iterator_impl<T, BOOST_DEDUCED_TYPENAME enable_if< has_type< range_mutable_iterator<T> > >::type>
+            : boost::mpl::true_
+        {
+        };
+
+        template<class T, class Enabler = void>
+        struct has_range_const_iterator_impl
+            : boost::mpl::false_
+        {
+        };
+
+        template<class T>
+        struct has_range_const_iterator_impl<T, BOOST_DEDUCED_TYPENAME enable_if< has_type< range_const_iterator<T> > >::type>
+            : boost::mpl::true_
+        {
+        };
+
+    } // namespace range_detail
+
+    template<class T>
+    struct has_range_iterator
+        : range_detail::has_range_iterator_impl<T>
+    {};
+
+    template<class T>
+    struct has_range_const_iterator
+        : range_detail::has_range_const_iterator_impl<T>
+    {};
+} // namespace boost
+
+#endif // include guard
+