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+//---------------------------------------------------------------------------//
+// Copyright (c) 2013-2014 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_DISCARD_ITERATOR_HPP
+#define BOOST_COMPUTE_ITERATOR_DISCARD_ITERATOR_HPP
+
+#include <string>
+#include <cstddef>
+#include <iterator>
+
+#include <boost/config.hpp>
+#include <boost/iterator/iterator_facade.hpp>
+
+#include <boost/compute/detail/meta_kernel.hpp>
+#include <boost/compute/type_traits/is_device_iterator.hpp>
+
+namespace boost {
+namespace compute {
+
+// forward declaration for discard_iterator
+class discard_iterator;
+
+namespace detail {
+
+// helper class which defines the iterator_facade super-class
+// type for discard_iterator
+struct discard_iterator_base
+{
+    typedef ::boost::iterator_facade<
+        ::boost::compute::discard_iterator,
+        void,
+        ::std::random_access_iterator_tag,
+        void *
+    > type;
+};
+
+template<class IndexExpr>
+struct discard_iterator_index_expr
+{
+    typedef void result_type;
+
+    discard_iterator_index_expr(const IndexExpr &expr)
+        : m_expr(expr)
+    {
+    }
+
+    IndexExpr m_expr;
+};
+
+template<class IndexExpr>
+inline meta_kernel& operator<<(meta_kernel &kernel,
+                               const discard_iterator_index_expr<IndexExpr> &expr)
+{
+    (void) expr;
+
+    return kernel;
+}
+
+} // end detail namespace
+
+/// \class discard_iterator
+/// \brief An iterator which discards all values written to it.
+///
+/// \see make_discard_iterator(), constant_iterator
+class discard_iterator : public detail::discard_iterator_base::type
+{
+public:
+    typedef detail::discard_iterator_base::type super_type;
+    typedef super_type::reference reference;
+    typedef super_type::difference_type difference_type;
+
+    discard_iterator(size_t index = 0)
+        : m_index(index)
+    {
+    }
+
+    discard_iterator(const discard_iterator &other)
+        : m_index(other.m_index)
+    {
+    }
+
+    discard_iterator& operator=(const discard_iterator &other)
+    {
+        if(this != &other){
+            m_index = other.m_index;
+        }
+
+        return *this;
+    }
+
+    ~discard_iterator()
+    {
+    }
+
+    /// \internal_
+    template<class Expr>
+    detail::discard_iterator_index_expr<Expr>
+    operator[](const Expr &expr) const
+    {
+        return detail::discard_iterator_index_expr<Expr>(expr);
+    }
+
+private:
+    friend class ::boost::iterator_core_access;
+
+    /// \internal_
+    reference dereference() const
+    {
+        return 0;
+    }
+
+    /// \internal_
+    bool equal(const discard_iterator &other) const
+    {
+        return m_index == other.m_index;
+    }
+
+    /// \internal_
+    void increment()
+    {
+        m_index++;
+    }
+
+    /// \internal_
+    void decrement()
+    {
+        m_index--;
+    }
+
+    /// \internal_
+    void advance(difference_type n)
+    {
+        m_index = static_cast<size_t>(static_cast<difference_type>(m_index) + n);
+    }
+
+    /// \internal_
+    difference_type distance_to(const discard_iterator &other) const
+    {
+        return static_cast<difference_type>(other.m_index - m_index);
+    }
+
+private:
+    size_t m_index;
+};
+
+/// Returns a new discard_iterator with \p index.
+///
+/// \param index the index of the iterator
+///
+/// \return a \c discard_iterator at \p index
+inline discard_iterator make_discard_iterator(size_t index = 0)
+{
+    return discard_iterator(index);
+}
+
+/// internal_ (is_device_iterator specialization for discard_iterator)
+template<>
+struct is_device_iterator<discard_iterator> : boost::true_type {};
+
+} // end compute namespace
+} // end boost namespace
+
+#endif // BOOST_COMPUTE_ITERATOR_DISCARD_ITERATOR_HPP