温酒读Qt：QObject 序篇

一、醉言醉语话夏娃

跟Qt框架打了这么久交道，Qt貌似对我的半斤八两知根知底，我对Qt的认知却还不到半斤八两。o(╥﹏╥)o
或许你知道Qt的meta-object和属性系统，或许你在写代码时无数次显示或者隐示的继承了QObject，不管人家是否乐意的就为她创造了无数个儿子、孙子、曾孙子、曾曾孙子… 但是，你真的了解QObject么？所以，我怀着满心的敬意决定掘无数Qt子类的祖坟，摸摸QObject这美女( 我自视她为Qt世界的夏娃)有个几斤几两~
当然，受限于个人能力水平，xxoo 可能不够深入，有兴趣的朋友可以yy一番，如果类似更深刻的狎妓经验分享一二，吾自当视如珍宝，细细品读，不甚感谢~
在这里插入图片描述

二、子子孙孙、无穷无尽（人话：超能干）

奉上一张QObject的族谱，看看他繁衍子孙后代的能力~ 哦，我不干净了！但，我干净过么~
WPS的pdf转图片工具还是个小趴菜，我这才1.6M的pdf居然转失败了，白瞎了我买的vip（吐槽一波）
另外，上次积分兑换的笔记本支架也是一言难尽（发散性吐槽）

只能缩小范围了，以Qt-Core模块为例：
在这里插入图片描述

在这里插入图片描述

…

太多了不贴不贴了，贴贴也是要跟夏娃贴贴。++（此处念佳佳）
所以用不着我废话说QObject到底有多少子子孙孙，子子孙孙又子子孙孙，反反复复无穷尽矣。

三、贴贴就贴贴

/****************************************************************************
**
** Copyright (C) 2016 The Qt Company Ltd.
** Copyright (C) 2013 Olivier Goffart <ogoffart@woboq.com>
** 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 QOBJECT_H
#define QOBJECT_H

#ifndef QT_NO_QOBJECT

#include <QtCore/qobjectdefs.h>
#include <QtCore/qstring.h>
#include <QtCore/qbytearray.h>
#include <QtCore/qlist.h>
#ifdef QT_INCLUDE_COMPAT
#include <QtCore/qcoreevent.h>
#endif
#include <QtCore/qscopedpointer.h>
#include <QtCore/qmetatype.h>

#include <QtCore/qobject_impl.h>

#if __has_include(<chrono>)
#  include <chrono>
#endif

QT_BEGIN_NAMESPACE


class QEvent;
class QTimerEvent;
class QChildEvent;
struct QMetaObject;
class QVariant;
class QObjectPrivate;
class QObject;
class QThread;
class QWidget;
class QAccessibleWidget;
#ifndef QT_NO_REGEXP
class QRegExp;
#endif
#if QT_CONFIG(regularexpression)
class QRegularExpression;
#endif
#if !QT_DEPRECATED_SINCE(5, 14) || QT_VERSION >= QT_VERSION_CHECK(6, 0, 0)
# define QT_NO_USERDATA
#endif
#ifndef QT_NO_USERDATA
class QObjectUserData;
#endif
struct QDynamicMetaObjectData;

typedef QList<QObject*> QObjectList;

Q_CORE_EXPORT void qt_qFindChildren_helper(const QObject *parent, const QString &name,
                                           const QMetaObject &mo, QList<void *> *list, Qt::FindChildOptions options);
Q_CORE_EXPORT void qt_qFindChildren_helper(const QObject *parent, const QRegExp &re,
                                           const QMetaObject &mo, QList<void *> *list, Qt::FindChildOptions options);
Q_CORE_EXPORT void qt_qFindChildren_helper(const QObject *parent, const QRegularExpression &re,
                                           const QMetaObject &mo, QList<void *> *list, Qt::FindChildOptions options);
Q_CORE_EXPORT QObject *qt_qFindChild_helper(const QObject *parent, const QString &name, const QMetaObject &mo, Qt::FindChildOptions options);

class Q_CORE_EXPORT QObjectData {
    Q_DISABLE_COPY(QObjectData)
public:
    QObjectData() = default;
    virtual ~QObjectData() = 0;
    QObject *q_ptr;
    QObject *parent;
    QObjectList children;

    uint isWidget : 1;
    uint blockSig : 1;
    uint wasDeleted : 1;
    uint isDeletingChildren : 1;
    uint sendChildEvents : 1;
    uint receiveChildEvents : 1;
    uint isWindow : 1; //for QWindow
    uint deleteLaterCalled : 1;
    uint unused : 24;
    int postedEvents;
    QDynamicMetaObjectData *metaObject;
    QMetaObject *dynamicMetaObject() const;

#ifdef QT_DEBUG
    enum { CheckForParentChildLoopsWarnDepth = 4096 };
#endif
};


class Q_CORE_EXPORT QObject
{
    Q_OBJECT

    Q_PROPERTY(QString objectName READ objectName WRITE setObjectName NOTIFY objectNameChanged)
    Q_DECLARE_PRIVATE(QObject)

public:
    Q_INVOKABLE explicit QObject(QObject *parent=nullptr);
    virtual ~QObject();

    virtual bool event(QEvent *event);
    virtual bool eventFilter(QObject *watched, QEvent *event);

#if defined(QT_NO_TRANSLATION) || defined(Q_CLANG_QDOC)
    static QString tr(const char *sourceText, const char * = nullptr, int = -1)
        { return QString::fromUtf8(sourceText); }
#if QT_DEPRECATED_SINCE(5, 0)
    QT_DEPRECATED static QString trUtf8(const char *sourceText, const char * = nullptr, int = -1)
        { return QString::fromUtf8(sourceText); }
#endif
#endif //QT_NO_TRANSLATION

    QString objectName() const;
    void setObjectName(const QString &name);

    inline bool isWidgetType() const { return d_ptr->isWidget; }
    inline bool isWindowType() const { return d_ptr->isWindow; }

    inline bool signalsBlocked() const noexcept { return d_ptr->blockSig; }
    bool blockSignals(bool b) noexcept;

    QThread *thread() const;
    void moveToThread(QThread *thread);

    int startTimer(int interval, Qt::TimerType timerType = Qt::CoarseTimer);
#if __has_include(<chrono>)
    Q_ALWAYS_INLINE
    int startTimer(std::chrono::milliseconds time, Qt::TimerType timerType = Qt::CoarseTimer)
    {
        return startTimer(int(time.count()), timerType);
    }
#endif
    void killTimer(int id);

    template<typename T>
    inline T findChild(const QString &aName = QString(), Qt::FindChildOptions options = Qt::FindChildrenRecursively) const
    {
        typedef typename std::remove_cv<typename std::remove_pointer<T>::type>::type ObjType;
        return static_cast<T>(qt_qFindChild_helper(this, aName, ObjType::staticMetaObject, options));
    }

    template<typename T>
    inline QList<T> findChildren(const QString &aName = QString(), Qt::FindChildOptions options = Qt::FindChildrenRecursively) const
    {
        typedef typename std::remove_cv<typename std::remove_pointer<T>::type>::type ObjType;
        QList<T> list;
        qt_qFindChildren_helper(this, aName, ObjType::staticMetaObject,
                                reinterpret_cast<QList<void *> *>(&list), options);
        return list;
    }

#ifndef QT_NO_REGEXP
#if QT_DEPRECATED_SINCE(5, 13)
    template<typename T>
    QT_DEPRECATED_X("Use findChildren(const QRegularExpression &, ...) instead.")
    inline QList<T> findChildren(const QRegExp &re, Qt::FindChildOptions options = Qt::FindChildrenRecursively) const
    {
        typedef typename std::remove_cv<typename std::remove_pointer<T>::type>::type ObjType;
        QList<T> list;
        qt_qFindChildren_helper(this, re, ObjType::staticMetaObject,
                                reinterpret_cast<QList<void *> *>(&list), options);
        return list;
    }
#endif
#endif

#if QT_CONFIG(regularexpression)
    template<typename T>
    inline QList<T> findChildren(const QRegularExpression &re, Qt::FindChildOptions options = Qt::FindChildrenRecursively) const
    {
        typedef typename std::remove_cv<typename std::remove_pointer<T>::type>::type ObjType;
        QList<T> list;
        qt_qFindChildren_helper(this, re, ObjType::staticMetaObject,
                                reinterpret_cast<QList<void *> *>(&list), options);
        return list;
    }
#endif // QT_CONFIG(regularexpression)

    inline const QObjectList &children() const { return d_ptr->children; }

    void setParent(QObject *parent);
    void installEventFilter(QObject *filterObj);
    void removeEventFilter(QObject *obj);

    static QMetaObject::Connection connect(const QObject *sender, const char *signal,
                        const QObject *receiver, const char *member, Qt::ConnectionType = Qt::AutoConnection);

    static QMetaObject::Connection connect(const QObject *sender, const QMetaMethod &signal,
                        const QObject *receiver, const QMetaMethod &method,
                        Qt::ConnectionType type = Qt::AutoConnection);

    inline QMetaObject::Connection connect(const QObject *sender, const char *signal,
                        const char *member, Qt::ConnectionType type = Qt::AutoConnection) const;

#ifdef Q_CLANG_QDOC
    template<typename PointerToMemberFunction>
    static QMetaObject::Connection connect(const QObject *sender, PointerToMemberFunction signal, const QObject *receiver, PointerToMemberFunction method, Qt::ConnectionType type = Qt::AutoConnection);
    template<typename PointerToMemberFunction, typename Functor>
    static QMetaObject::Connection connect(const QObject *sender, PointerToMemberFunction signal, Functor functor);
    template<typename PointerToMemberFunction, typename Functor>
    static QMetaObject::Connection connect(const QObject *sender, PointerToMemberFunction signal, const QObject *context, Functor functor, Qt::ConnectionType type = Qt::AutoConnection);
#else
    //Connect a signal to a pointer to qobject member function
    template <typename Func1, typename Func2>
    static inline QMetaObject::Connection connect(const typename QtPrivate::FunctionPointer<Func1>::Object *sender, Func1 signal,
                                     const typename QtPrivate::FunctionPointer<Func2>::Object *receiver, Func2 slot,
                                     Qt::ConnectionType type = Qt::AutoConnection)
    {
        typedef QtPrivate::FunctionPointer<Func1> SignalType;
        typedef QtPrivate::FunctionPointer<Func2> SlotType;

        Q_STATIC_ASSERT_X(QtPrivate::HasQ_OBJECT_Macro<typename SignalType::Object>::Value,
                          "No Q_OBJECT in the class with the signal");

        //compilation error if the arguments does not match.
        Q_STATIC_ASSERT_X(int(SignalType::ArgumentCount) >= int(SlotType::ArgumentCount),
                          "The slot requires more arguments than the signal provides.");
        Q_STATIC_ASSERT_X((QtPrivate::CheckCompatibleArguments<typename SignalType::Arguments, typename SlotType::Arguments>::value),
                          "Signal and slot arguments are not compatible.");
        Q_STATIC_ASSERT_X((QtPrivate::AreArgumentsCompatible<typename SlotType::ReturnType, typename SignalType::ReturnType>::value),
                          "Return type of the slot is not compatible with the return type of the signal.");

        const int *types = nullptr;
        if (type == Qt::QueuedConnection || type == Qt::BlockingQueuedConnection)
            types = QtPrivate::ConnectionTypes<typename SignalType::Arguments>::types();

        return connectImpl(sender, reinterpret_cast<void **>(&signal),
                           receiver, reinterpret_cast<void **>(&slot),
                           new QtPrivate::QSlotObject<Func2, typename QtPrivate::List_Left<typename SignalType::Arguments, SlotType::ArgumentCount>::Value,
                                           typename SignalType::ReturnType>(slot),
                            type, types, &SignalType::Object::staticMetaObject);
    }

    //connect to a function pointer  (not a member)
    template <typename Func1, typename Func2>
    static inline typename std::enable_if<int(QtPrivate::FunctionPointer<Func2>::ArgumentCount) >= 0, QMetaObject::Connection>::type
            connect(const typename QtPrivate::FunctionPointer<Func1>::Object *sender, Func1 signal, Func2 slot)
    {
        return connect(sender, signal, sender, slot, Qt::DirectConnection);
    }

    //connect to a function pointer  (not a member)
    template <typename Func1, typename Func2>
    static inline typename std::enable_if<int(QtPrivate::FunctionPointer<Func2>::ArgumentCount) >= 0 &&
                                          !QtPrivate::FunctionPointer<Func2>::IsPointerToMemberFunction, QMetaObject::Connection>::type
            connect(const typename QtPrivate::FunctionPointer<Func1>::Object *sender, Func1 signal, const QObject *context, Func2 slot,
                    Qt::ConnectionType type = Qt::AutoConnection)
    {
        typedef QtPrivate::FunctionPointer<Func1> SignalType;
        typedef QtPrivate::FunctionPointer<Func2> SlotType;

        Q_STATIC_ASSERT_X(QtPrivate::HasQ_OBJECT_Macro<typename SignalType::Object>::Value,
                          "No Q_OBJECT in the class with the signal");

        //compilation error if the arguments does not match.
        Q_STATIC_ASSERT_X(int(SignalType::ArgumentCount) >= int(SlotType::ArgumentCount),
                          "The slot requires more arguments than the signal provides.");
        Q_STATIC_ASSERT_X((QtPrivate::CheckCompatibleArguments<typename SignalType::Arguments, typename SlotType::Arguments>::value),
                          "Signal and slot arguments are not compatible.");
        Q_STATIC_ASSERT_X((QtPrivate::AreArgumentsCompatible<typename SlotType::ReturnType, typename SignalType::ReturnType>::value),
                          "Return type of the slot is not compatible with the return type of the signal.");

        const int *types = nullptr;
        if (type == Qt::QueuedConnection || type == Qt::BlockingQueuedConnection)
            types = QtPrivate::ConnectionTypes<typename SignalType::Arguments>::types();

        return connectImpl(sender, reinterpret_cast<void **>(&signal), context, nullptr,
                           new QtPrivate::QStaticSlotObject<Func2,
                                                 typename QtPrivate::List_Left<typename SignalType::Arguments, SlotType::ArgumentCount>::Value,
                                                 typename SignalType::ReturnType>(slot),
                           type, types, &SignalType::Object::staticMetaObject);
    }

    //connect to a functor
    template <typename Func1, typename Func2>
    static inline typename std::enable_if<QtPrivate::FunctionPointer<Func2>::ArgumentCount == -1, QMetaObject::Connection>::type
            connect(const typename QtPrivate::FunctionPointer<Func1>::Object *sender, Func1 signal, Func2 slot)
    {
        return connect(sender, signal, sender, std::move(slot), Qt::DirectConnection);
    }

    //connect to a functor, with a "context" object defining in which event loop is going to be executed
    template <typename Func1, typename Func2>
    static inline typename std::enable_if<QtPrivate::FunctionPointer<Func2>::ArgumentCount == -1, QMetaObject::Connection>::type
            connect(const typename QtPrivate::FunctionPointer<Func1>::Object *sender, Func1 signal, const QObject *context, Func2 slot,
                    Qt::ConnectionType type = Qt::AutoConnection)
    {
        typedef QtPrivate::FunctionPointer<Func1> SignalType;
        const int FunctorArgumentCount = QtPrivate::ComputeFunctorArgumentCount<Func2 , typename SignalType::Arguments>::Value;

        Q_STATIC_ASSERT_X((FunctorArgumentCount >= 0),
                          "Signal and slot arguments are not compatible.");
        const int SlotArgumentCount = (FunctorArgumentCount >= 0) ? FunctorArgumentCount : 0;
        typedef typename QtPrivate::FunctorReturnType<Func2, typename QtPrivate::List_Left<typename SignalType::Arguments, SlotArgumentCount>::Value>::Value SlotReturnType;

        Q_STATIC_ASSERT_X((QtPrivate::AreArgumentsCompatible<SlotReturnType, typename SignalType::ReturnType>::value),
                          "Return type of the slot is not compatible with the return type of the signal.");

        Q_STATIC_ASSERT_X(QtPrivate::HasQ_OBJECT_Macro<typename SignalType::Object>::Value,
                          "No Q_OBJECT in the class with the signal");

        const int *types = nullptr;
        if (type == Qt::QueuedConnection || type == Qt::BlockingQueuedConnection)
            types = QtPrivate::ConnectionTypes<typename SignalType::Arguments>::types();

        return connectImpl(sender, reinterpret_cast<void **>(&signal), context, nullptr,
                           new QtPrivate::QFunctorSlotObject<Func2, SlotArgumentCount,
                                typename QtPrivate::List_Left<typename SignalType::Arguments, SlotArgumentCount>::Value,
                                typename SignalType::ReturnType>(std::move(slot)),
                           type, types, &SignalType::Object::staticMetaObject);
    }
#endif //Q_CLANG_QDOC

    static bool disconnect(const QObject *sender, const char *signal,
                           const QObject *receiver, const char *member);
    static bool disconnect(const QObject *sender, const QMetaMethod &signal,
                           const QObject *receiver, const QMetaMethod &member);
    inline bool disconnect(const char *signal = nullptr,
                           const QObject *receiver = nullptr, const char *member = nullptr) const
        { return disconnect(this, signal, receiver, member); }
    inline bool disconnect(const QObject *receiver, const char *member = nullptr) const
        { return disconnect(this, nullptr, receiver, member); }
    static bool disconnect(const QMetaObject::Connection &);

#ifdef Q_CLANG_QDOC
    template<typename PointerToMemberFunction>
    static bool disconnect(const QObject *sender, PointerToMemberFunction signal, const QObject *receiver, PointerToMemberFunction method);
#else
    template <typename Func1, typename Func2>
    static inline bool disconnect(const typename QtPrivate::FunctionPointer<Func1>::Object *sender, Func1 signal,
                                  const typename QtPrivate::FunctionPointer<Func2>::Object *receiver, Func2 slot)
    {
        typedef QtPrivate::FunctionPointer<Func1> SignalType;
        typedef QtPrivate::FunctionPointer<Func2> SlotType;

        Q_STATIC_ASSERT_X(QtPrivate::HasQ_OBJECT_Macro<typename SignalType::Object>::Value,
                          "No Q_OBJECT in the class with the signal");

        //compilation error if the arguments does not match.
        Q_STATIC_ASSERT_X((QtPrivate::CheckCompatibleArguments<typename SignalType::Arguments, typename SlotType::Arguments>::value),
                          "Signal and slot arguments are not compatible.");

        return disconnectImpl(sender, reinterpret_cast<void **>(&signal), receiver, reinterpret_cast<void **>(&slot),
                              &SignalType::Object::staticMetaObject);
    }
    template <typename Func1>
    static inline bool disconnect(const typename QtPrivate::FunctionPointer<Func1>::Object *sender, Func1 signal,
                                  const QObject *receiver, void **zero)
    {
        // This is the overload for when one wish to disconnect a signal from any slot. (slot=nullptr)
        // Since the function template parameter cannot be deduced from '0', we use a
        // dummy void ** parameter that must be equal to 0
        Q_ASSERT(!zero);
        typedef QtPrivate::FunctionPointer<Func1> SignalType;
        return disconnectImpl(sender, reinterpret_cast<void **>(&signal), receiver, zero,
                              &SignalType::Object::staticMetaObject);
    }
#endif //Q_CLANG_QDOC


#if QT_VERSION < QT_VERSION_CHECK(6, 0, 0)
    void dumpObjectTree(); // ### Qt 6: remove
    void dumpObjectInfo(); // ### Qt 6: remove
#endif
    void dumpObjectTree() const;
    void dumpObjectInfo() const;

#ifndef QT_NO_PROPERTIES
    bool setProperty(const char *name, const QVariant &value);
    QVariant property(const char *name) const;
    QList<QByteArray> dynamicPropertyNames() const;
#endif // QT_NO_PROPERTIES

#ifndef QT_NO_USERDATA
    QT_DEPRECATED_VERSION_5_14
    static uint registerUserData();
    QT_DEPRECATED_VERSION_X_5_14("Use setProperty()")
    void setUserData(uint id, QObjectUserData* data);
    QT_DEPRECATED_VERSION_X_5_14("Use property()")
    QObjectUserData* userData(uint id) const;
#endif // QT_NO_USERDATA

Q_SIGNALS:
    void destroyed(QObject * = nullptr);
    void objectNameChanged(const QString &objectName, QPrivateSignal);

public:
    inline QObject *parent() const { return d_ptr->parent; }

    inline bool inherits(const char *classname) const
        { return const_cast<QObject *>(this)->qt_metacast(classname) != nullptr; }

public Q_SLOTS:
    void deleteLater();

protected:
    QObject *sender() const;
    int senderSignalIndex() const;
    int receivers(const char* signal) const;
    bool isSignalConnected(const QMetaMethod &signal) const;

    virtual void timerEvent(QTimerEvent *event);
    virtual void childEvent(QChildEvent *event);
    virtual void customEvent(QEvent *event);

    virtual void connectNotify(const QMetaMethod &signal);
    virtual void disconnectNotify(const QMetaMethod &signal);

protected:
    QObject(QObjectPrivate &dd, QObject *parent = nullptr);

protected:
    QScopedPointer<QObjectData> d_ptr;

    static const QMetaObject staticQtMetaObject;
    friend inline const QMetaObject *qt_getQtMetaObject() noexcept;

    friend struct QMetaObject;
    friend struct QMetaObjectPrivate;
    friend class QMetaCallEvent;
    friend class QApplication;
    friend class QApplicationPrivate;
    friend class QCoreApplication;
    friend class QCoreApplicationPrivate;
    friend class QWidget;
    friend class QAccessibleWidget;
    friend class QThreadData;

private:
    Q_DISABLE_COPY(QObject)
    Q_PRIVATE_SLOT(d_func(), void _q_reregisterTimers(void *))

private:
    static QMetaObject::Connection connectImpl(const QObject *sender, void **signal,
                                               const QObject *receiver, void **slotPtr,
                                               QtPrivate::QSlotObjectBase *slot, Qt::ConnectionType type,
                                               const int *types, const QMetaObject *senderMetaObject);

    static bool disconnectImpl(const QObject *sender, void **signal, const QObject *receiver, void **slot,
                               const QMetaObject *senderMetaObject);

};

inline QMetaObject::Connection QObject::connect(const QObject *asender, const char *asignal,
                                            const char *amember, Qt::ConnectionType atype) const
{ return connect(asender, asignal, this, amember, atype); }

inline const QMetaObject *qt_getQtMetaObject() noexcept
{ return &QObject::staticQtMetaObject; }

#ifndef QT_NO_USERDATA
class Q_CORE_EXPORT QObjectUserData {
    Q_DISABLE_COPY(QObjectUserData)
public:
    QObjectUserData() = default;
    virtual ~QObjectUserData();
};
#endif

#if QT_DEPRECATED_SINCE(5, 0)
template<typename T>
inline QT_DEPRECATED T qFindChild(const QObject *o, const QString &name = QString())
{ return o->findChild<T>(name); }

template<typename T>
inline QT_DEPRECATED QList<T> qFindChildren(const QObject *o, const QString &name = QString())
{
    return o->findChildren<T>(name);
}

#if !defined(QT_NO_REGEXP) || defined(Q_CLANG_QDOC)
template<typename T>
inline QT_DEPRECATED QList<T> qFindChildren(const QObject *o, const QRegExp &re)
{
    return o->findChildren<T>(re);
}
#endif

#endif //QT_DEPRECATED

template <class T>
inline T qobject_cast(QObject *object)
{
    typedef typename std::remove_cv<typename std::remove_pointer<T>::type>::type ObjType;
    Q_STATIC_ASSERT_X(QtPrivate::HasQ_OBJECT_Macro<ObjType>::Value,
                    "qobject_cast requires the type to have a Q_OBJECT macro");
    return static_cast<T>(ObjType::staticMetaObject.cast(object));
}

template <class T>
inline T qobject_cast(const QObject *object)
{
    typedef typename std::remove_cv<typename std::remove_pointer<T>::type>::type ObjType;
    Q_STATIC_ASSERT_X(QtPrivate::HasQ_OBJECT_Macro<ObjType>::Value,
                      "qobject_cast requires the type to have a Q_OBJECT macro");
    return static_cast<T>(ObjType::staticMetaObject.cast(object));
}


template <class T> inline const char * qobject_interface_iid()
{ return nullptr; }


#if defined(Q_CLANG_QDOC)
#  define Q_DECLARE_INTERFACE(IFace, IId)
#elif !defined(Q_MOC_RUN)
#  define Q_DECLARE_INTERFACE(IFace, IId) \
    template <> inline const char *qobject_interface_iid<IFace *>() \
    { return IId; } \
    template <> inline IFace *qobject_cast<IFace *>(QObject *object) \
    { return reinterpret_cast<IFace *>((object ? object->qt_metacast(IId) : nullptr)); } \
    template <> inline IFace *qobject_cast<IFace *>(const QObject *object) \
    { return reinterpret_cast<IFace *>((object ? const_cast<QObject *>(object)->qt_metacast(IId) : nullptr)); }
#endif // Q_MOC_RUN

#ifndef QT_NO_DEBUG_STREAM
Q_CORE_EXPORT QDebug operator<<(QDebug, const QObject *);
#endif

class QSignalBlocker
{
public:
    inline explicit QSignalBlocker(QObject *o) noexcept;
    inline explicit QSignalBlocker(QObject &o) noexcept;
    inline ~QSignalBlocker();

    inline QSignalBlocker(QSignalBlocker &&other) noexcept;
    inline QSignalBlocker &operator=(QSignalBlocker &&other) noexcept;

    inline void reblock() noexcept;
    inline void unblock() noexcept;
private:
    Q_DISABLE_COPY(QSignalBlocker)
    QObject * m_o;
    bool m_blocked;
    bool m_inhibited;
};

QSignalBlocker::QSignalBlocker(QObject *o) noexcept
    : m_o(o),
      m_blocked(o && o->blockSignals(true)),
      m_inhibited(false)
{}

QSignalBlocker::QSignalBlocker(QObject &o) noexcept
    : m_o(&o),
      m_blocked(o.blockSignals(true)),
      m_inhibited(false)
{}

QSignalBlocker::QSignalBlocker(QSignalBlocker &&other) noexcept
    : m_o(other.m_o),
      m_blocked(other.m_blocked),
      m_inhibited(other.m_inhibited)
{
    other.m_o = nullptr;
}

QSignalBlocker &QSignalBlocker::operator=(QSignalBlocker &&other) noexcept
{
    if (this != &other) {
        // if both *this and other block the same object's signals:
        // unblock *this iff our dtor would unblock, but other's wouldn't
        if (m_o != other.m_o || (!m_inhibited && other.m_inhibited))
            unblock();
        m_o = other.m_o;
        m_blocked = other.m_blocked;
        m_inhibited = other.m_inhibited;
        // disable other:
        other.m_o = nullptr;
    }
    return *this;
}

QSignalBlocker::~QSignalBlocker()
{
    if (m_o && !m_inhibited)
        m_o->blockSignals(m_blocked);
}

void QSignalBlocker::reblock() noexcept
{
    if (m_o) m_o->blockSignals(true);
    m_inhibited = false;
}

void QSignalBlocker::unblock() noexcept
{
    if (m_o) m_o->blockSignals(m_blocked);
    m_inhibited = true;
}

namespace QtPrivate {
    inline QObject & deref_for_methodcall(QObject &o) { return  o; }
    inline QObject & deref_for_methodcall(QObject *o) { return *o; }
}
#define Q_SET_OBJECT_NAME(obj) QT_PREPEND_NAMESPACE(QtPrivate)::deref_for_methodcall(obj).setObjectName(QLatin1String(#obj))

QT_END_NAMESPACE

#endif

#endif // QOBJECT_H