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diff --git a/src/corelib/kernel/qiterable.h b/src/corelib/kernel/qiterable.h
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+/****************************************************************************
+**
+** Copyright (C) 2020 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the QtCore module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 3 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL3 included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 3 requirements
+** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 2.0 or (at your option) the GNU General
+** Public license version 3 or any later version approved by the KDE Free
+** Qt Foundation. The licenses are as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-2.0.html and
+** https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#ifndef QITERABLE_H
+#define QITERABLE_H
+
+#include <QtCore/qglobal.h>
+#include <QtCore/qtypeinfo.h>
+#include <QtCore/qmetacontainer.h>
+#include <QtCore/qmetatype.h>
+
+QT_BEGIN_NAMESPACE
+
+class Q_CORE_EXPORT QSequentialIterable
+{
+    uint m_revision = 0;
+    const void *m_iterable = nullptr;
+    QMetaSequence m_metaSequence;
+
+public:
+    struct Q_CORE_EXPORT const_iterator
+    {
+    private:
+        const QSequentialIterable *m_iterable = nullptr;
+        void *m_iterator = nullptr;
+        QAtomicInt *m_ref = nullptr;
+
+        friend class QSequentialIterable;
+        explicit const_iterator(const QSequentialIterable *iterable, void *iterator);
+
+    public:
+        ~const_iterator();
+
+        const_iterator(const const_iterator &other);
+
+        const_iterator& operator=(const const_iterator &other);
+
+        const QVariant operator*() const;
+        bool operator==(const const_iterator &o) const;
+        bool operator!=(const const_iterator &o) const;
+        const_iterator &operator++();
+        const_iterator operator++(int);
+        const_iterator &operator--();
+        const_iterator operator--(int);
+        const_iterator &operator+=(int j);
+        const_iterator &operator-=(int j);
+        const_iterator operator+(int j) const;
+        const_iterator operator-(int j) const;
+        friend inline const_iterator operator+(int j, const const_iterator &k) { return k + j; }
+    };
+
+    friend struct const_iterator;
+
+    template<class T>
+    QSequentialIterable(const T *p)
+      : m_iterable(p)
+      , m_metaSequence(QMetaSequence::fromContainer<T>())
+    {
+    }
+
+    QSequentialIterable() = default;
+
+    QSequentialIterable(const QMetaSequence &metaSequence, const void *iterable)
+        : m_iterable(iterable)
+        , m_metaSequence(metaSequence)
+    {
+    }
+
+    const_iterator begin() const;
+    const_iterator end() const;
+
+    QVariant at(qsizetype idx) const;
+    qsizetype size() const;
+
+    bool canReverseIterate() const;
+
+    const void *constIterable() const { return m_iterable; }
+    QMetaSequence metaSequence() const { return m_metaSequence; }
+};
+
+namespace QtPrivate {
+
+template<typename From>
+struct QSequentialIterableConvertFunctor
+{
+    QSequentialIterable operator()(const From &f) const
+    {
+        return QSequentialIterable(&f);
+    }
+};
+
+template<typename T>
+struct SequentialValueTypeIsMetaType<T, true>
+{
+    static bool registerConverter(int id)
+    {
+        const int toId = qMetaTypeId<QSequentialIterable>();
+        if (!QMetaType::hasRegisteredConverterFunction(id, toId)) {
+            QSequentialIterableConvertFunctor<T> o;
+            return QMetaType::registerConverter<T, QSequentialIterable>(o);
+        }
+        return true;
+    }
+};
+
+}
+
+Q_DECLARE_TYPEINFO(QSequentialIterable, Q_MOVABLE_TYPE);
+Q_DECLARE_TYPEINFO(QSequentialIterable::const_iterator, Q_MOVABLE_TYPE);
+
+QT_END_NAMESPACE
+
+#endif // QITERABLE_H