QtWidgets: replace 0 with \nullptr in documentation

Replace 0 with \nullptr in the documentation.
As a drive-by also replace some 0 with nullptr in the corresponding
code.

Change-Id: I5e5bc1ae892f270d7c3419db1c179053561f1b26
Reviewed-by: Paul Wicking <paul.wicking@qt.io>

12 files changed, 90 insertions, 88 deletions

diff --git a/src/widgets/dialogs/qdialog.cpp b/src/widgets/dialogs/qdialog.cpp
index ebbd2fa9ea..cc04110a30 100644
--- a/src/widgets/dialogs/qdialog.cpp
+++ b/src/widgets/dialogs/qdialog.cpp
@@ -422,7 +422,7 @@ QDialog::~QDialog()
 /*!
   \internal
   This function is called by the push button \a pushButton when it
-  becomes the default button. If \a pushButton is 0, the dialogs
+  becomes the default button. If \a pushButton is \nullptr, the dialogs
   default default button becomes the default button. This is what a
   push button calls when it loses focus.
 */
@@ -1014,7 +1014,7 @@ void QDialog::setExtension(QWidget* extension)
 /*!
     \obsolete
 
-    Returns the dialog's extension or 0 if no extension has been
+    Returns the dialog's extension or \nullptr if no extension has been
     defined.
 
     Instead of using this functionality, we recommend that you simply call
diff --git a/src/widgets/dialogs/qmessagebox.cpp b/src/widgets/dialogs/qmessagebox.cpp
index ac1952a642..c9818624fb 100644
--- a/src/widgets/dialogs/qmessagebox.cpp
+++ b/src/widgets/dialogs/qmessagebox.cpp
@@ -834,7 +834,7 @@ QMessageBox::QMessageBox(QWidget *parent)
     The message box is an \l{Qt::ApplicationModal} {application modal}
     dialog box.
 
-    On \macos, if \a parent is not 0 and you want your message box
+    On \macos, if \a parent is not \nullptr and you want your message box
     to appear as a Qt::Sheet of that parent, set the message box's
     \l{setWindowModality()} {window modality} to Qt::WindowModal
     (default). Otherwise, the message box will be a standard dialog.
@@ -983,7 +983,7 @@ QMessageBox::StandardButton QMessageBox::standardButton(QAbstractButton *button)
     \since 4.2
 
     Returns a pointer corresponding to the standard button \a which,
-    or 0 if the standard button doesn't exist in this message box.
+    or \nullptr if the standard button doesn't exist in this message box.
 
     \sa standardButtons, standardButton()
 */
@@ -1106,7 +1106,7 @@ void QMessageBoxPrivate::detectEscapeButton()
     \since 4.2
 
     Returns the button that was clicked by the user,
-    or 0 if the user hit the \uicontrol Esc key and
+    or \nullptr if the user hit the \uicontrol Esc key and
     no \l{setEscapeButton()}{escape button} was set.
 
     If exec() hasn't been called yet, returns nullptr.
@@ -1173,7 +1173,7 @@ void QMessageBox::setDefaultButton(QMessageBox::StandardButton button)
 /*! \since 5.2
 
     Sets the checkbox \a cb on the message dialog. The message box takes ownership of the checkbox.
-    The argument \a cb can be 0 to remove an existing checkbox from the message box.
+    The argument \a cb can be \nullptr to remove an existing checkbox from the message box.
 
     \sa checkBox()
 */
@@ -1205,7 +1205,7 @@ void QMessageBox::setCheckBox(QCheckBox *cb)
 
 /*! \since 5.2
 
-    Returns the checkbox shown on the dialog. This is 0 if no checkbox is set.
+    Returns the checkbox shown on the dialog. This is \nullptr if no checkbox is set.
     \sa setCheckBox()
 */
 
@@ -1570,7 +1570,7 @@ QList<QAbstractButton *> QMessageBox::buttons() const
     \since 4.5
 
     Returns the button role for the specified \a button. This function returns
-    \l InvalidRole if \a button is 0 or has not been added to the message box.
+    \l InvalidRole if \a button is \nullptr or has not been added to the message box.
 
     \sa buttons(), addButton()
 */
@@ -1835,7 +1835,7 @@ void QMessageBox::about(QWidget *parent, const QString &title, const QString &te
 
 /*!
     Displays a simple message box about Qt, with the given \a title
-    and centered over \a parent (if \a parent is not 0). The message
+    and centered over \a parent (if \a parent is not \nullptr). The message
     includes the version number of Qt being used by the application.
 
     This is useful for inclusion in the \uicontrol Help menu of an application,
diff --git a/src/widgets/dialogs/qwizard.cpp b/src/widgets/dialogs/qwizard.cpp
index 59168ba14d..9345a4b583 100644
--- a/src/widgets/dialogs/qwizard.cpp
+++ b/src/widgets/dialogs/qwizard.cpp
@@ -2374,8 +2374,8 @@ void QWizard::removePage(int id)
 /*!
     \fn QWizardPage *QWizard::page(int id) const
 
-    Returns the page with the given \a id, or 0 if there is no such
-    page.
+    Returns the page with the given \a id, or \nullptr if there is no
+    such page.
 
     \sa addPage(), setPage()
 */
@@ -2462,8 +2462,8 @@ int QWizard::startId() const
 }
 
 /*!
-    Returns a pointer to the current page, or 0 if there is no current
-    page (e.g., before the wizard is shown).
+    Returns a pointer to the current page, or \nullptr if there is no
+    current page (e.g., before the wizard is shown).
 
     This is equivalent to calling page(currentId()).
 
@@ -2954,7 +2954,7 @@ void QWizard::setDefaultProperty(const char *className, const char *property,
 
     Passing 0 shows no side widget.
 
-    When the \a widget is not 0 the wizard reparents it.
+    When the \a widget is not \nullptr the wizard reparents it.
 
     Any previous side widget is hidden.
 
@@ -2963,7 +2963,7 @@ void QWizard::setDefaultProperty(const char *className, const char *property,
 
     All widgets set here will be deleted by the wizard when it is
     destroyed unless you separately reparent the widget after setting
-    some other side widget (or 0).
+    some other side widget (or \nullptr).
 
     By default, no side widget is present.
 */
@@ -2981,7 +2981,7 @@ void QWizard::setSideWidget(QWidget *widget)
 /*!
     \since 4.7
 
-    Returns the widget on the left side of the wizard or 0.
+    Returns the widget on the left side of the wizard or \nullptr.
 
     By default, no side widget is present.
 */
@@ -3969,7 +3969,7 @@ void QWizardPage::registerField(const QString &name, QWidget *widget, const char
 }
 
 /*!
-    Returns the wizard associated with this page, or 0 if this page
+    Returns the wizard associated with this page, or \nullptr if this page
     hasn't been inserted into a QWizard yet.
 
     \sa QWizard::addPage(), QWizard::setPage()
diff --git a/src/widgets/kernel/qactiongroup.cpp b/src/widgets/kernel/qactiongroup.cpp
index 7934ae1d90..4786437d7e 100644
--- a/src/widgets/kernel/qactiongroup.cpp
+++ b/src/widgets/kernel/qactiongroup.cpp
@@ -316,8 +316,8 @@ bool QActionGroup::isEnabled() const
 }
 
 /*!
-  Returns the currently checked action in the group, or 0 if none
-  are checked.
+  Returns the currently checked action in the group, or \nullptr if
+  none are checked.
 */
 QAction *QActionGroup::checkedAction() const
 {
diff --git a/src/widgets/kernel/qapplication.cpp b/src/widgets/kernel/qapplication.cpp
index 53e1d13455..3594b5c902 100644
--- a/src/widgets/kernel/qapplication.cpp
+++ b/src/widgets/kernel/qapplication.cpp
@@ -784,7 +784,7 @@ QWidget *QApplication::activeModalWidget()
 
 /*!
     Cleans up any window system resources that were allocated by this
-    application. Sets the global variable \c qApp to 0.
+    application. Sets the global variable \c qApp to \nullptr.
 */
 
 QApplication::~QApplication()
@@ -893,8 +893,8 @@ void qt_cleanup()
 /*!
     \fn QWidget *QApplication::widgetAt(const QPoint &point)
 
-    Returns the widget at global screen position \a point, or 0 if there is no
-    Qt widget there.
+    Returns the widget at global screen position \a point, or \nullptr
+    if there is no Qt widget there.
 
     This function can be slow.
 
@@ -904,9 +904,9 @@ QWidget *QApplication::widgetAt(const QPoint &p)
 {
     QWidget *window = QApplication::topLevelAt(p);
     if (!window)
-        return 0;
+        return nullptr;
 
-    QWidget *child = 0;
+    QWidget *child = nullptr;
 
     if (!window->testAttribute(Qt::WA_TransparentForMouseEvents))
         child = window->childAt(window->mapFromGlobal(p));
@@ -942,8 +942,8 @@ QWidget *QApplication::widgetAt(const QPoint &p)
 
     \overload
 
-    Returns the widget at global screen position (\a x, \a y), or 0 if there is
-    no Qt widget there.
+    Returns the widget at global screen position (\a x, \a y), or
+    \nullptr if there is no Qt widget there.
 */
 
 /*!
@@ -1728,8 +1728,8 @@ QWidgetList QApplication::allWidgets()
 }
 
 /*!
-    Returns the application widget that has the keyboard input focus, or 0 if
-    no widget in this application has the focus.
+    Returns the application widget that has the keyboard input focus,
+    or \nullptr if no widget in this application has the focus.
 
     \sa QWidget::setFocus(), QWidget::hasFocus(), activeWindow(), focusChanged()
 */
@@ -1797,7 +1797,7 @@ void QApplicationPrivate::setFocusWidget(QWidget *focus, Qt::FocusReason reason)
 
 /*!
     Returns the application top-level window that has the keyboard input focus,
-    or 0 if no application window has the focus. There might be an
+    or \nullptr if no application window has the focus. There might be an
     activeWindow() even if there is no focusWidget(), for example if no widget
     in that window accepts key events.
 
diff --git a/src/widgets/kernel/qgridlayout.cpp b/src/widgets/kernel/qgridlayout.cpp
index f1c6c96a6d..4f2b505e32 100644
--- a/src/widgets/kernel/qgridlayout.cpp
+++ b/src/widgets/kernel/qgridlayout.cpp
@@ -1330,8 +1330,8 @@ QLayoutItem *QGridLayout::itemAt(int index) const
 /*!
     \since 4.4
 
-    Returns the layout item that occupies cell (\a row, \a column), or 0 if
-    the cell is empty.
+    Returns the layout item that occupies cell (\a row, \a column), or
+    \nullptr if the cell is empty.
 
     \sa getItemPosition(), indexOf()
 */
@@ -1346,7 +1346,7 @@ QLayoutItem *QGridLayout::itemAtPosition(int row, int column) const
             return box->item();
         }
     }
-    return 0;
+    return nullptr;
 }
 
 /*!
diff --git a/src/widgets/kernel/qlayout.cpp b/src/widgets/kernel/qlayout.cpp
index eac5674161..090abc883d 100644
--- a/src/widgets/kernel/qlayout.cpp
+++ b/src/widgets/kernel/qlayout.cpp
@@ -474,8 +474,8 @@ QRect QLayout::contentsRect() const
 
 
 /*!
-    Returns the parent widget of this layout, or 0 if this layout is
-    not installed on any widget.
+    Returns the parent widget of this layout, or \nullptr if this
+    layout is not installed on any widget.
 
     If the layout is a sub-layout, this function returns the parent
     widget of the parent layout.
@@ -490,11 +490,11 @@ QWidget *QLayout::parentWidget() const
             QLayout *parentLayout = qobject_cast<QLayout*>(parent());
             if (Q_UNLIKELY(!parentLayout)) {
                 qWarning("QLayout::parentWidget: A layout can only have another layout as a parent.");
-                return 0;
+                return nullptr;
             }
             return parentLayout->parentWidget();
         } else {
-            return 0;
+            return nullptr;
         }
     } else {
         Q_ASSERT(parent() && parent()->isWidgetType());
@@ -950,8 +950,8 @@ void QLayout::setMenuBar(QWidget *widget)
 }
 
 /*!
-    Returns the menu bar set for this layout, or 0 if no menu bar is
-    set.
+    Returns the menu bar set for this layout, or \nullptr if no
+    menu bar is set.
 */
 
 QWidget *QLayout::menuBar() const
@@ -1130,8 +1130,9 @@ bool QLayout::activate()
 
     Searches for widget \a from and replaces it with widget \a to if found.
     Returns the layout item that contains the widget \a from on success.
-    Otherwise \c 0 is returned. If \a options contains \c Qt::FindChildrenRecursively
-    (the default), sub-layouts are searched for doing the replacement.
+    Otherwise \nullptr is returned.
+    If \a options contains \c Qt::FindChildrenRecursively  (the default),
+    sub-layouts are searched for doing the replacement.
     Any other flag in \a options is ignored.
 
     Notice that the returned item therefore might not belong to this layout,
diff --git a/src/widgets/kernel/qlayoutitem.cpp b/src/widgets/kernel/qlayoutitem.cpp
index 25890e888b..9e6d1c5eac 100644
--- a/src/widgets/kernel/qlayoutitem.cpp
+++ b/src/widgets/kernel/qlayoutitem.cpp
@@ -309,24 +309,24 @@ void QLayoutItem::invalidate()
 
 /*!
     If this item is a QLayout, it is returned as a QLayout; otherwise
-    0 is returned. This function provides type-safe casting.
+    \nullptr is returned. This function provides type-safe casting.
 
     \sa spacerItem(), widget()
 */
-QLayout * QLayoutItem::layout()
+QLayout *QLayoutItem::layout()
 {
-    return 0;
+    return nullptr;
 }
 
 /*!
     If this item is a QSpacerItem, it is returned as a QSpacerItem;
-    otherwise 0 is returned. This function provides type-safe casting.
+    otherwise \nullptr is returned. This function provides type-safe casting.
 
     \sa layout(), widget()
 */
-QSpacerItem * QLayoutItem::spacerItem()
+QSpacerItem *QLayoutItem::spacerItem()
 {
-    return 0;
+    return nullptr;
 }
 
 /*!
@@ -354,7 +354,7 @@ QSpacerItem * QSpacerItem::spacerItem()
 
 /*!
     If this item manages a QWidget, returns that widget. Otherwise,
-    \c nullptr is returned.
+    \nullptr is returned.
 
     \note While the functions layout() and spacerItem() perform casts, this
     function returns another object: QLayout and QSpacerItem inherit QLayoutItem,
@@ -362,9 +362,9 @@ QSpacerItem * QSpacerItem::spacerItem()
 
     \sa layout(), spacerItem()
 */
-QWidget * QLayoutItem::widget()
+QWidget *QLayoutItem::widget()
 {
-    return 0;
+    return nullptr;
 }
 
 /*!
diff --git a/src/widgets/kernel/qopenglwidget.cpp b/src/widgets/kernel/qopenglwidget.cpp
index 89f860150f..cf15614680 100644
--- a/src/widgets/kernel/qopenglwidget.cpp
+++ b/src/widgets/kernel/qopenglwidget.cpp
@@ -1118,8 +1118,8 @@ void QOpenGLWidget::setTextureFormat(GLenum texFormat)
 /*!
     \return the active internal texture format if the widget has already
     initialized, the requested format if one was set but the widget has not yet
-    been made visible, or 0 if setTextureFormat() was not called and the widget
-    has not yet been made visible.
+    been made visible, or \nullptr if setTextureFormat() was not called and the
+    widget has not yet been made visible.
 
     \since 5.10
  */
diff --git a/src/widgets/kernel/qstackedlayout.cpp b/src/widgets/kernel/qstackedlayout.cpp
index 7430d833db..0412dc188d 100644
--- a/src/widgets/kernel/qstackedlayout.cpp
+++ b/src/widgets/kernel/qstackedlayout.cpp
@@ -378,20 +378,20 @@ void QStackedLayout::setCurrentWidget(QWidget *widget)
 
 
 /*!
-    Returns the current widget, or 0 if there are no widgets in this
-    layout.
+    Returns the current widget, or \nullptr if there are no widgets
+    in this layout.
 
     \sa currentIndex(), setCurrentWidget()
 */
 QWidget *QStackedLayout::currentWidget() const
 {
     Q_D(const QStackedLayout);
-    return d->index >= 0 ? d->list.at(d->index)->widget() : 0;
+    return d->index >= 0 ? d->list.at(d->index)->widget() : nullptr;
 }
 
 /*!
-    Returns the widget at the given \a index, or 0 if there is no
-    widget at the given position.
+    Returns the widget at the given \a index, or \nullptr if there is
+    no widget at the given position.
 
     \sa currentWidget(), indexOf()
 */
@@ -399,7 +399,7 @@ QWidget *QStackedLayout::widget(int index) const
 {
     Q_D(const QStackedLayout);
      if (index < 0 || index >= d->list.size())
-        return 0;
+        return nullptr;
     return d->list.at(index)->widget();
 }
 
diff --git a/src/widgets/kernel/qwidget.cpp b/src/widgets/kernel/qwidget.cpp
index 3b1d82df18..87cc150530 100644
--- a/src/widgets/kernel/qwidget.cpp
+++ b/src/widgets/kernel/qwidget.cpp
@@ -511,10 +511,10 @@ void QWidget::setAutoFillBackground(bool enabled)
     Every widget's constructor accepts one or two standard arguments:
 
     \list 1
-        \li  \c{QWidget *parent = 0} is the parent of the new widget. If it is 0
-            (the default), the new widget will be a window. If not, it will be
-            a child of \e parent, and be constrained by \e parent's geometry
-            (unless you specify Qt::Window as window flag).
+        \li  \c{QWidget *parent = \nullptr} is the parent of the new widget.
+            If it is \nullptr (the default), the new widget will be a window.
+            If not, it will be a child of \e parent, and be constrained by
+            \e parent's geometry (unless you specify Qt::Window as window flag).
         \li  \c{Qt::WindowFlags f = 0} (where available) sets the window flags;
             the default is suitable for almost all widgets, but to get, for
             example, a window without a window system frame, you must use
@@ -1003,7 +1003,7 @@ struct QWidgetExceptionCleaner
     Constructs a widget which is a child of \a parent, with  widget
     flags set to \a f.
 
-    If \a parent is 0, the new widget becomes a window. If
+    If \a parent is \nullptr, the new widget becomes a window. If
     \a parent is another widget, this widget becomes a child window
     inside \a parent. The new widget is deleted when its \a parent is
     deleted.
@@ -2497,12 +2497,12 @@ void QWidgetPrivate::deactivateWidgetCleanup()
 
     The window identifier type depends on the underlying window
     system, see \c qwindowdefs.h for the actual definition. If there
-    is no widget with this identifier, 0 is returned.
+    is no widget with this identifier, \nullptr is returned.
 */
 
 QWidget *QWidget::find(WId id)
 {
-    return QWidgetPrivate::mapper ? QWidgetPrivate::mapper->value(id, 0) : 0;
+    return QWidgetPrivate::mapper ? QWidgetPrivate::mapper->value(id, 0) : nullptr;
 }
 
 
@@ -3279,7 +3279,7 @@ void QWidget::addActions(QList<QAction*> actions)
 
 /*!
     Inserts the action \a action to this widget's list of actions,
-    before the action \a before. It appends the action if \a before is 0 or
+    before the action \a before. It appends the action if \a before is \nullptr or
     \a before is not a valid action for this widget.
 
     A QWidget should only have one of each action.
@@ -3313,7 +3313,7 @@ void QWidget::insertAction(QAction *before, QAction *action)
 
 /*!
     Inserts the actions \a actions to this widget's list of actions,
-    before the action \a before. It appends the action if \a before is 0 or
+    before the action \a before. It appends the action if \a before is \nullptr or
     \a before is not a valid action for this widget.
 
     A QWidget can have at most one of each action.
@@ -4336,7 +4336,8 @@ QWidget *QWidget::window() const
     \since 4.4
 
     Returns the native parent for this widget, i.e. the next ancestor widget
-    that has a system identifier, or 0 if it does not have any native parent.
+    that has a system identifier, or \nullptr if it does not have any native
+    parent.
 
     \sa effectiveWinId()
 */
@@ -5273,7 +5274,7 @@ QPixmap QWidget::grab(const QRect &rectangle)
     \brief The graphicsEffect function returns a pointer to the
     widget's graphics effect.
 
-    If the widget has no graphics effect, 0 is returned.
+    If the widget has no graphics effect, \nullptr is returned.
 
     \since 4.6
 
@@ -5917,10 +5918,10 @@ QPixmap QWidgetEffectSourcePrivate::pixmap(Qt::CoordinateSystem system, QPoint *
 
     Finds the nearest widget embedded in a graphics proxy widget along the chain formed by this
     widget and its ancestors. The search starts at \a origin (inclusive).
-    If successful, the function returns the proxy that embeds the widget, or 0 if no embedded
-    widget was found.
+    If successful, the function returns the proxy that embeds the widget, or \nullptr if no
+    embedded widget was found.
 */
-QGraphicsProxyWidget * QWidgetPrivate::nearestGraphicsProxyWidget(const QWidget *origin)
+QGraphicsProxyWidget *QWidgetPrivate::nearestGraphicsProxyWidget(const QWidget *origin)
 {
     if (origin) {
         QWExtra *extra = origin->d_func()->extra;
@@ -5928,7 +5929,7 @@ QGraphicsProxyWidget * QWidgetPrivate::nearestGraphicsProxyWidget(const QWidget
             return extra->proxyWidget;
         return nearestGraphicsProxyWidget(origin->parentWidget());
     }
-    return 0;
+    return nullptr;
 }
 #endif
 
@@ -6400,7 +6401,7 @@ void QWidget::setWindowRole(const QString &role)
 
 
 /*!
-    Sets the widget's focus proxy to widget \a w. If \a w is 0, the
+    Sets the widget's focus proxy to widget \a w. If \a w is \nullptr, the
     function resets this widget to have no focus proxy.
 
     Some widgets can "have focus", but create a child widget, such as
@@ -6433,15 +6434,15 @@ void QWidget::setFocusProxy(QWidget * w)
 
 
 /*!
-    Returns the focus proxy, or 0 if there is no focus proxy.
+    Returns the focus proxy, or \nullptr if there is no focus proxy.
 
     \sa setFocusProxy()
 */
 
-QWidget * QWidget::focusProxy() const
+QWidget *QWidget::focusProxy() const
 {
     Q_D(const QWidget);
-    return d->extra ? (QWidget *)d->extra->focus_proxy : 0;
+    return d->extra ? (QWidget *)d->extra->focus_proxy : nullptr;
 }
 
 
@@ -8819,7 +8820,7 @@ QSize QWidget::minimumSizeHint() const
 /*!
     \fn QWidget *QWidget::parentWidget() const
 
-    Returns the parent of this widget, or 0 if it does not have any
+    Returns the parent of this widget, or \nullptr if it does not have any
     parent widget.
 */
 
@@ -10229,7 +10230,7 @@ QRegion QWidget::mask() const
 }
 
 /*!
-    Returns the layout manager that is installed on this widget, or 0
+    Returns the layout manager that is installed on this widget, or \nullptr
     if no layout manager is installed.
 
     The layout manager sets the geometry of the widget's children
@@ -12117,14 +12118,14 @@ bool QWidgetPrivate::navigateToDirection(Direction direction)
     Searches for a widget that is positioned in the \a direction, starting
     from the current focusWidget.
 
-    Returns the pointer to a found widget or 0, if there was no widget in
-    that direction.
+    Returns the pointer to a found widget or \nullptr, if there was no widget
+    in that direction.
 */
 QWidget *QWidgetPrivate::widgetInNavigationDirection(Direction direction)
 {
     const QWidget *sourceWidget = QApplication::focusWidget();
     if (!sourceWidget)
-        return 0;
+        return nullptr;
     const QRect sourceRect = sourceWidget->rect().translated(sourceWidget->mapToGlobal(QPoint()));
     const int sourceX =
             (direction == DirectionNorth || direction == DirectionSouth) ?
@@ -12138,7 +12139,7 @@ QWidget *QWidgetPrivate::widgetInNavigationDirection(Direction direction)
     const QPoint sourceCenter = sourceRect.center();
     const QWidget *sourceWindow = sourceWidget->window();
 
-    QWidget *targetWidget = 0;
+    QWidget *targetWidget = nullptr;
     int shortestDistance = INT_MAX;
 
     const auto targetCandidates = QApplication::allWidgets();
@@ -12805,7 +12806,7 @@ void QWidget::releaseKeyboard()
     Returns the widget that is currently grabbing the mouse input.
 
     If no widget in this application is currently grabbing the mouse,
-    0 is returned.
+    \nullptr is returned.
 
     \sa grabMouse(), keyboardGrabber()
 */
@@ -12822,7 +12823,7 @@ QWidget *QWidget::mouseGrabber()
     Returns the widget that is currently grabbing the keyboard input.
 
     If no widget in this application is currently grabbing the
-    keyboard, 0 is returned.
+    keyboard, \nullptr is returned.
 
     \sa grabMouse(), mouseGrabber()
 */
diff --git a/src/widgets/styles/qstyleoption.cpp b/src/widgets/styles/qstyleoption.cpp
index 97631a5841..88031a9f1e 100644
--- a/src/widgets/styles/qstyleoption.cpp
+++ b/src/widgets/styles/qstyleoption.cpp
@@ -3270,7 +3270,7 @@ QStyleOptionViewItem::QStyleOptionViewItem(int version)
     \fn template <typename T> T qstyleoption_cast<T>(const QStyleOption *option)
     \relates QStyleOption
 
-    Returns a T or 0 depending on the \l{QStyleOption::type}{type} and
+    Returns a T or \nullptr depending on the \l{QStyleOption::type}{type} and
     \l{QStyleOption::version}{version} of the given \a option.
 
     Example:
@@ -3285,7 +3285,7 @@ QStyleOptionViewItem::QStyleOptionViewItem(int version)
     \overload
     \relates QStyleOption
 
-    Returns a T or 0 depending on the type of the given \a option.
+    Returns a T or \nullptr depending on the type of the given \a option.
 */
 
 #if QT_CONFIG(tabwidget)
@@ -4006,7 +4006,7 @@ QStyleHintReturnVariant::~QStyleHintReturnVariant()
     \fn template <typename T> T qstyleoption_cast<T>(const QStyleHintReturn *hint)
     \relates QStyleHintReturn
 
-    Returns a T or 0 depending on the \l{QStyleHintReturn::type}{type}
+    Returns a T or \nullptr depending on the \l{QStyleHintReturn::type}{type}
     and \l{QStyleHintReturn::version}{version} of \a hint.
 
     Example:
@@ -4021,7 +4021,7 @@ QStyleHintReturnVariant::~QStyleHintReturnVariant()
     \overload
     \relates QStyleHintReturn
 
-    Returns a T or 0 depending on the type of \a hint.
+    Returns a T or \nullptr depending on the type of \a hint.
 */
 
 #if !defined(QT_NO_DEBUG_STREAM)