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diff --git a/boost/geometry/util/transform_variant.hpp b/boost/geometry/util/transform_variant.hpp
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+// Boost.Geometry (aka GGL, Generic Geometry Library)
+
+// Copyright (c) 2007-2012 Barend Gehrels, Amsterdam, the Netherlands.
+// Copyright (c) 2008-2012 Bruno Lalande, Paris, France.
+// Copyright (c) 2009-2012 Mateusz Loskot, London, UK.
+
+// Parts of Boost.Geometry are redesigned from Geodan's Geographic Library
+// (geolib/GGL), copyright (c) 1995-2010 Geodan, Amsterdam, the Netherlands.
+
+// 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)
+
+#ifndef BOOST_GEOMETRY_UTIL_TRANSFORM_VARIANT_HPP
+#define BOOST_GEOMETRY_UTIL_TRANSFORM_VARIANT_HPP
+
+
+#include <boost/mpl/transform.hpp>
+#include <boost/variant/variant_fwd.hpp>
+
+
+namespace boost { namespace geometry
+{
+
+
+/*!
+    \brief Meta-function that takes a Sequence type, an MPL lambda
+        expression and an optional Inserter and returns a variant type over
+        the same types as the initial variant type, each transformed using
+        the lambda expression.
+    \ingroup utility
+    \par Example
+    \code
+        typedef mpl::vector<int, float, long> types;
+        typedef transform_variant<types, add_pointer<_> > transformed;
+        typedef variant<int*, float*, long*> result;
+        BOOST_MPL_ASSERT(( equal<result, transformed> ));
+    \endcode
+*/
+template <typename Sequence, typename Op, typename In = boost::mpl::na>
+struct transform_variant:
+    make_variant_over<
+        typename mpl::transform<
+            Sequence,
+            Op,
+            In
+        >::type
+    >
+{};
+
+
+/*!
+    \brief Meta-function that takes a boost::variant type and an MPL lambda
+        expression and returns a variant type over the same types as the
+        initial variant type, each transformed using the lambda expression.
+    \ingroup utility
+    \par Example
+    \code
+        typedef variant<int, float, long> variant_type;
+        typedef transform_variant<variant_type, add_pointer<_> > transformed;
+        typedef variant<int*, float*, long*> result;
+        BOOST_MPL_ASSERT(( equal<result, transformed> ));
+    \endcode
+*/
+template <BOOST_VARIANT_ENUM_PARAMS(typename T), typename Op>
+struct transform_variant<variant<BOOST_VARIANT_ENUM_PARAMS(T)>, Op, boost::mpl::na> :
+    make_variant_over<
+        typename mpl::transform<
+            typename variant<BOOST_VARIANT_ENUM_PARAMS(T)>::types,
+            Op
+        >::type
+    >
+{};
+
+
+}} // namespace boost::geometry
+
+
+#endif // BOOST_GEOMETRY_UTIL_TRANSFORM_VARIANT_HPP