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diff --git a/include/unotools/weakref.hxx b/include/unotools/weakref.hxx
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+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+/*
+ * This file is part of LibreOffice published API.
+ */
+#pragma once
+
+#include <sal/config.h>
+
+#include <com/sun/star/uno/Reference.hxx>
+#include <com/sun/star/uno/XInterface.hpp>
+#include <cppuhelper/weakref.hxx>
+#include <cppuhelper/weak.hxx>
+#include <rtl/ref.hxx>
+
+namespace unotools
+{
+/** The WeakReference<> holds a weak reference to an object.
+
+    That object must implement the css::uno::XWeak interface.
+
+    The WeakReference itself is *not* thread safe, just as
+    Reference itself isn't, but the implementation of the listeners etc.
+    behind it *is* thread-safe, so multiple threads can have their own
+    WeakReferences to the same XWeak object.
+
+    @tparam interface_type Must be a C++ implementation class type, not a UNO interface type.  (See
+    the C++20 requires-clause on the get member.  That clause is not put on the class as a whole to
+    avoid overly tight requirements on when interface_type needs to be complete.)
+*/
+template <class interface_type>
+class SAL_WARN_UNUSED WeakReference : public com::sun::star::uno::WeakReferenceHelper
+{
+public:
+    /** Default ctor.  Creates an empty weak reference.
+    */
+    WeakReference()
+        : WeakReferenceHelper()
+    {
+    }
+
+    /** Copy ctor.  Initialize this reference with a hard reference.
+
+        @param rRef another hard ref
+    */
+    WeakReference(const rtl::Reference<interface_type>& rRef)
+        : WeakReferenceHelper(css::uno::Reference<css::uno::XWeak>(rRef))
+    {
+    }
+
+    /** Copy ctor.  Initialize this reference with a hard reference.
+
+        @param rRef another hard ref
+    */
+    WeakReference(interface_type& rRef)
+        : WeakReferenceHelper(&rRef)
+    {
+    }
+
+    /** Copy ctor.  Initialize this reference with a hard reference.
+
+        @param rRef another hard ref
+    */
+    WeakReference(interface_type* pRef)
+        : WeakReferenceHelper(
+              css::uno::Reference<css::uno::XWeak>(static_cast<cppu::OWeakObject*>(pRef)))
+    {
+    }
+
+    /** Releases this reference and takes over hard reference xInt.
+        If the implementation behind xInt does not support XWeak
+        or XInt is null, then this reference is null.
+
+        @param xInt another hard reference
+    */
+    WeakReference& operator=(const rtl::Reference<interface_type>& xInt)
+    {
+        WeakReferenceHelper::operator=(xInt);
+        return *this;
+    }
+
+    WeakReference& operator=(rtl::Reference<interface_type>&& xInt)
+    {
+        WeakReferenceHelper::operator=(std::move(xInt));
+        return *this;
+    }
+
+    WeakReference& operator=(interface_type* pInt)
+    {
+        WeakReferenceHelper::operator=(
+            css::uno::Reference<css::uno::XWeak>(static_cast<::cppu::OWeakObject*>(pInt)));
+        return *this;
+    }
+
+    /**  Gets a hard reference to the object.
+
+         @return hard reference or null, if the weakly referenced interface has gone
+    */
+    rtl::Reference<interface_type> SAL_CALL get() const
+#if !(defined __clang__ && __clang_major__ <= 15)
+        requires(!cppu::detail::isUnoInterfaceType<interface_type>)
+#endif
+    {
+        css::uno::Reference<css::uno::XInterface> xInterface = WeakReferenceHelper::get();
+        // If XInterface is an ambiguous base of interface_type, we have to use dynamic_cast,
+        // otherwise we can use the faster static_cast.
+        if constexpr (std::is_convertible_v<interface_type*, css::uno::XInterface*>)
+            return static_cast<interface_type*>(xInterface.get());
+        else
+            return dynamic_cast<interface_type*>(xInterface.get());
+    }
+
+    /**  Gets a hard reference to the object.
+
+         @return hard reference or null, if the weakly referenced interface has gone
+    */
+    operator ::rtl::Reference<interface_type>() const { return get(); }
+};
+}
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */