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+//---------------------------------------------------------------------------//
+// Copyright (c) 2013 Kyle Lutz <kyle.r.lutz@gmail.com>
+//
+// Distributed under 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
+//
+// See http://boostorg.github.com/compute for more information.
+//---------------------------------------------------------------------------//
+
+#ifndef BOOST_COMPUTE_ITERATOR_TRANSFORM_ITERATOR_HPP
+#define BOOST_COMPUTE_ITERATOR_TRANSFORM_ITERATOR_HPP
+
+#include <cstddef>
+#include <iterator>
+
+#include <boost/config.hpp>
+#include <boost/iterator/iterator_adaptor.hpp>
+
+#include <boost/compute/functional.hpp>
+#include <boost/compute/detail/meta_kernel.hpp>
+#include <boost/compute/detail/is_buffer_iterator.hpp>
+#include <boost/compute/detail/read_write_single_value.hpp>
+#include <boost/compute/iterator/detail/get_base_iterator_buffer.hpp>
+#include <boost/compute/type_traits/is_device_iterator.hpp>
+#include <boost/compute/type_traits/result_of.hpp>
+
+namespace boost {
+namespace compute {
+
+// forward declaration for transform_iterator
+template<class InputIterator, class UnaryFunction>
+class transform_iterator;
+
+namespace detail {
+
+// meta-function returning the value_type for a transform_iterator
+template<class InputIterator, class UnaryFunction>
+struct make_transform_iterator_value_type
+{
+    typedef typename std::iterator_traits<InputIterator>::value_type value_type;
+
+    typedef typename boost::compute::result_of<UnaryFunction(value_type)>::type type;
+};
+
+// helper class which defines the iterator_adaptor super-class
+// type for transform_iterator
+template<class InputIterator, class UnaryFunction>
+class transform_iterator_base
+{
+public:
+    typedef ::boost::iterator_adaptor<
+        ::boost::compute::transform_iterator<InputIterator, UnaryFunction>,
+        InputIterator,
+        typename make_transform_iterator_value_type<InputIterator, UnaryFunction>::type,
+        typename std::iterator_traits<InputIterator>::iterator_category,
+        typename make_transform_iterator_value_type<InputIterator, UnaryFunction>::type
+    > type;
+};
+
+template<class InputIterator, class UnaryFunction, class IndexExpr>
+struct transform_iterator_index_expr
+{
+    typedef typename
+        make_transform_iterator_value_type<
+            InputIterator,
+            UnaryFunction
+        >::type result_type;
+
+    transform_iterator_index_expr(const InputIterator &input_iter,
+                                  const UnaryFunction &transform_expr,
+                                  const IndexExpr &index_expr)
+        : m_input_iter(input_iter),
+          m_transform_expr(transform_expr),
+          m_index_expr(index_expr)
+    {
+    }
+
+    InputIterator m_input_iter;
+    UnaryFunction m_transform_expr;
+    IndexExpr m_index_expr;
+};
+
+template<class InputIterator, class UnaryFunction, class IndexExpr>
+inline meta_kernel& operator<<(meta_kernel &kernel,
+                               const transform_iterator_index_expr<InputIterator,
+                                                                   UnaryFunction,
+                                                                   IndexExpr> &expr)
+{
+    return kernel << expr.m_transform_expr(expr.m_input_iter[expr.m_index_expr]);
+}
+
+} // end detail namespace
+
+/// \class transform_iterator
+/// \brief A transform iterator adaptor.
+///
+/// The transform_iterator adaptor applies a unary function to each element
+/// produced from the underlying iterator when dereferenced.
+///
+/// For example, to copy from an input range to an output range while taking
+/// the absolute value of each element:
+///
+/// \snippet test/test_transform_iterator.cpp copy_abs
+///
+/// \see buffer_iterator, make_transform_iterator()
+template<class InputIterator, class UnaryFunction>
+class transform_iterator :
+    public detail::transform_iterator_base<InputIterator, UnaryFunction>::type
+{
+public:
+    typedef typename
+        detail::transform_iterator_base<InputIterator,
+                                        UnaryFunction>::type super_type;
+    typedef typename super_type::value_type value_type;
+    typedef typename super_type::reference reference;
+    typedef typename super_type::base_type base_type;
+    typedef typename super_type::difference_type difference_type;
+    typedef UnaryFunction unary_function;
+
+    transform_iterator(InputIterator iterator, UnaryFunction transform)
+        : super_type(iterator),
+          m_transform(transform)
+    {
+    }
+
+    transform_iterator(const transform_iterator<InputIterator,
+                                                UnaryFunction> &other)
+        : super_type(other.base()),
+          m_transform(other.m_transform)
+    {
+    }
+
+    transform_iterator<InputIterator, UnaryFunction>&
+    operator=(const transform_iterator<InputIterator,
+                                       UnaryFunction> &other)
+    {
+        if(this != &other){
+            super_type::operator=(other);
+
+            m_transform = other.m_transform;
+        }
+
+        return *this;
+    }
+
+    ~transform_iterator()
+    {
+    }
+
+    size_t get_index() const
+    {
+        return super_type::base().get_index();
+    }
+
+    const buffer& get_buffer() const
+    {
+        return detail::get_base_iterator_buffer(*this);
+    }
+
+    template<class IndexExpression>
+    detail::transform_iterator_index_expr<InputIterator, UnaryFunction, IndexExpression>
+    operator[](const IndexExpression &expr) const
+    {
+        return detail::transform_iterator_index_expr<InputIterator,
+                                                     UnaryFunction,
+                                                     IndexExpression>(super_type::base(),
+                                                                      m_transform,
+                                                                      expr);
+    }
+
+private:
+    friend class ::boost::iterator_core_access;
+
+    reference dereference() const
+    {
+        const context &context = super_type::base().get_buffer().get_context();
+        command_queue queue(context, context.get_device());
+
+        detail::meta_kernel k("read");
+        size_t output_arg = k.add_arg<value_type *>(memory_object::global_memory, "output");
+        k << "*output = " << m_transform(super_type::base()[k.lit(0)]) << ";";
+
+        kernel kernel = k.compile(context);
+
+        buffer output_buffer(context, sizeof(value_type));
+
+        kernel.set_arg(output_arg, output_buffer);
+
+        queue.enqueue_task(kernel);
+
+        return detail::read_single_value<value_type>(output_buffer, queue);
+    }
+
+private:
+    UnaryFunction m_transform;
+};
+
+/// Returns a transform_iterator for \p iterator with \p transform.
+///
+/// \param iterator the underlying iterator
+/// \param transform the unary transform function
+///
+/// \return a \c transform_iterator for \p iterator with \p transform
+///
+/// For example, to create an iterator which returns the square-root of each
+/// value in a \c vector<int>:
+/// \code
+/// auto sqrt_iterator = make_transform_iterator(vec.begin(), sqrt<int>());
+/// \endcode
+template<class InputIterator, class UnaryFunction>
+inline transform_iterator<InputIterator, UnaryFunction>
+make_transform_iterator(InputIterator iterator, UnaryFunction transform)
+{
+    return transform_iterator<InputIterator,
+                              UnaryFunction>(iterator, transform);
+}
+
+/// \internal_ (is_device_iterator specialization for transform_iterator)
+template<class InputIterator, class UnaryFunction>
+struct is_device_iterator<
+    transform_iterator<InputIterator, UnaryFunction> > : boost::true_type {};
+
+} // end compute namespace
+} // end boost namespace
+
+#endif // BOOST_COMPUTE_ITERATOR_TRANSFORM_ITERATOR_HPP