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diff --git a/include/comphelper/weakbag.hxx b/include/comphelper/weakbag.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 .
+ */
+
+#ifndef INCLUDED_COMPHELPER_WEAKBAG_HXX
+#define INCLUDED_COMPHELPER_WEAKBAG_HXX
+
+#include <sal/config.h>
+
+#include <vector>
+#include <com/sun/star/uno/Reference.h>
+#include <cppuhelper/weakref.hxx>
+#include <osl/diagnose.h>
+
+namespace comphelper {
+
+/**
+   A bag of UNO weak references.
+*/
+template< typename T > class WeakBag {
+public:
+    /**
+       Add a new weak reference.
+
+       The implementation keeps the amount of memory consumed linear in the
+       number of living references added, not linear in the number of total
+       references added.
+
+       @param e
+       a non-null reference.
+    */
+    void add(css::uno::Reference< T > const & e) {
+        OSL_ASSERT(e.is());
+        for (auto i = m_list.begin(); i != m_list.end();) {
+            if (css::uno::Reference< T >(*i).is()) {
+                ++i;
+            } else {
+                i = m_list.erase(i);
+            }
+        }
+        m_list.push_back(css::uno::WeakReference< T >(e));
+    }
+
+    /**
+       Remove a living reference.
+
+       @return
+       a living reference, or null if there are none.
+    */
+    css::uno::Reference< T > remove() {
+        while (!m_list.empty()) {
+            css::uno::Reference< T > r(m_list.back());
+            m_list.pop_back();
+            if (r.is()) {
+                return r;
+            }
+        }
+        return css::uno::Reference< T >();
+    }
+
+private:
+    std::vector< css::uno::WeakReference< T > > m_list;
+};
+
+}
+
+#endif
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */