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diff --git a/boost/log/attributes/constant.hpp b/boost/log/attributes/constant.hpp
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+/*
+ *          Copyright Andrey Semashev 2007 - 2014.
+ * 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)
+ */
+/*!
+ * \file   constant.hpp
+ * \author Andrey Semashev
+ * \date   15.04.2007
+ *
+ * The header contains implementation of a constant attribute.
+ */
+
+#ifndef BOOST_LOG_ATTRIBUTES_CONSTANT_HPP_INCLUDED_
+#define BOOST_LOG_ATTRIBUTES_CONSTANT_HPP_INCLUDED_
+
+#include <boost/move/core.hpp>
+#include <boost/move/utility.hpp>
+#include <boost/type_traits/remove_reference.hpp>
+#include <boost/log/detail/config.hpp>
+#include <boost/log/detail/embedded_string_type.hpp>
+#include <boost/log/attributes/attribute.hpp>
+#include <boost/log/attributes/attribute_cast.hpp>
+#include <boost/log/attributes/attribute_value_impl.hpp>
+#include <boost/log/detail/header.hpp>
+
+#ifdef BOOST_HAS_PRAGMA_ONCE
+#pragma once
+#endif
+
+namespace boost {
+
+BOOST_LOG_OPEN_NAMESPACE
+
+namespace attributes {
+
+/*!
+ * \brief A class of an attribute that holds a single constant value
+ *
+ * The constant is a simplest and one of the most frequently used types of attributes.
+ * It stores a constant value, which it eventually returns as its value each time
+ * requested.
+ */
+template< typename T >
+class constant :
+    public attribute
+{
+public:
+    //! Attribute value type
+    typedef T value_type;
+
+protected:
+    //! Factory implementation
+    class BOOST_SYMBOL_VISIBLE impl :
+        public attribute_value_impl< value_type >
+    {
+        //! Base type
+        typedef attribute_value_impl< value_type > base_type;
+
+    public:
+        /*!
+         * Constructor with the stored value initialization
+         */
+        explicit impl(value_type const& value) : base_type(value) {}
+        /*!
+         * Constructor with the stored value initialization
+         */
+        explicit impl(BOOST_RV_REF(value_type) value) : base_type(boost::move(value)) {}
+    };
+
+public:
+    /*!
+     * Constructor with the stored value initialization
+     */
+    explicit constant(value_type const& value) : attribute(new impl(value)) {}
+    /*!
+     * Constructor with the stored value initialization
+     */
+    explicit constant(BOOST_RV_REF(value_type) value) : attribute(new impl(boost::move(value))) {}
+    /*!
+     * Constructor for casting support
+     */
+    explicit constant(cast_source const& source) : attribute(source.as< impl >())
+    {
+    }
+
+    /*!
+     * \return Reference to the contained value.
+     */
+    value_type const& get() const
+    {
+        return static_cast< impl* >(this->get_impl())->get();
+    }
+};
+
+/*!
+ * The function constructs a \c constant attribute containing the provided value.
+ * The function automatically converts C string arguments to \c std::basic_string objects.
+ */
+template< typename T >
+inline constant<
+    typename boost::log::aux::make_embedded_string_type<
+        typename remove_reference< T >::type
+    >::type
+> make_constant(BOOST_FWD_REF(T) val)
+{
+    typedef typename boost::log::aux::make_embedded_string_type<
+        typename remove_reference< T >::type
+    >::type value_type;
+    return constant< value_type >(boost::forward< T >(val));
+}
+
+} // namespace attributes
+
+BOOST_LOG_CLOSE_NAMESPACE // namespace log
+
+} // namespace boost
+
+#include <boost/log/detail/footer.hpp>
+
+#endif // BOOST_LOG_ATTRIBUTES_CONSTANT_HPP_INCLUDED_