Q_OBJECT

Undocumented in source but is binding to C++. You might be able to learn more by searching the web for its name.
extern (C++)
enum Q_OBJECT = q{ public: /+ QT_WARNING_PUSH Q_OBJECT_NO_OVERRIDE_WARNING +/ extern(C++) extern } ~ exportOnWindows ~ q{static __gshared const(imported!q{qt.core.objectdefs}.QMetaObject) staticMetaObject; extern(C++) override /+ virtual +/ const(imported!q{qt.core.objectdefs}.QMetaObject)* metaObject() const; extern(C++) override /+ virtual +/ void* qt_metacast(const(char)* ); extern(C++) override /+ virtual +/ int qt_metacall(imported!q{qt.core.objectdefs}.QMetaObject.Call, int, void** ); } ~ QT_TR_FUNCTIONS ~ q{ private: /+ Q_OBJECT_NO_ATTRIBUTES_WARNING +/ /+ Q_DECL_HIDDEN_STATIC_METACALL +/ static void qt_static_metacall(imported!"qt.core.object".QObject , imported!q{qt.core.objectdefs}.QMetaObject.Call, int, void** ); /+ QT_WARNING_POP +/ extern(C++) struct QPrivateSignal {}};

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