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diff --git a/Source/WTF/wtf/Box.h b/Source/WTF/wtf/Box.h
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+/*
+ * Copyright (C) 2015 Apple Inc. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE INC. OR
+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
+ * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 
+ */
+
+#ifndef WTF_Box_h
+#define WTF_Box_h
+
+#include <wtf/RefPtr.h>
+#include <wtf/ThreadSafeRefCounted.h>
+
+namespace WTF {
+
+// Box<T> is a reference-counted pointer to T that allocates T using FastMalloc and prepends a reference
+// count to it.
+template<typename T>
+class Box {
+public:
+    Box()
+    {
+    }
+
+    Box(std::nullptr_t)
+    {
+    }
+
+    template<typename... Arguments>
+    static Box create(Arguments&&... arguments)
+    {
+        Box result;
+        result.m_data = adoptRef(new Data(std::forward<Arguments>(arguments)...));
+        return result;
+    }
+
+    T* get() const { return &m_data->value; }
+
+    T& operator*() const { return m_data->value; }
+    T* operator->() const { return &m_data->value; }
+
+    explicit operator bool() { return m_data; }
+    
+private:
+    struct Data : ThreadSafeRefCounted<Data> {
+        template<typename... Arguments>
+        Data(Arguments&&... arguments)
+            : value(std::forward<Arguments>(arguments)...)
+        {
+        }
+        
+        T value;
+    };
+
+    RefPtr<Data> m_data;
+};
+
+} // namespace WTF
+
+using WTF::Box;
+
+#endif // WTF_Box_h
+