Q_OBJECT_D

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_D = q{ public: extern(C++) extern static __gshared const(imported!q{qt.core.objectdefs}.QMetaObject) staticMetaObject; extern(C++) override const(imported!q{qt.core.objectdefs}.QMetaObject)* metaObject() const { import qt.core.object; return qt.core.object.QObject.d_ptr.metaObject ? qt.core.object.QObject.d_ptr.dynamicMetaObject() : &staticMetaObject; } extern(C++) override void * qt_metacast(const(char)* _clname) { import qt.core.objectdefs; if (!_clname) return null; import core.stdc.string; if (!core.stdc..string.strcmp(_clname, qt.core.objectdefs.MetaObjectImpl!(typeof(this)).stringdata.stringdata0.ptr)) return static_cast!(void*)(this); return super.qt_metacast(_clname); } extern(C++) override int qt_metacall(imported!q{qt.core.objectdefs}.QMetaObject.Call _c, int _id, void **_a) { import qt.core.objectdefs; _id = super.qt_metacall(_c, _id, _a); if (_id < 0) return _id; alias allMethods = qt.core.objectdefs.MetaObjectImpl!(typeof(this)).allMethods; if (_c == qt.core.objectdefs.QMetaObject.Call.InvokeMetaMethod) { if (_id < allMethods.length) qt_static_metacall(this, _c, _id, _a); _id -= allMethods.length; } else if (_c == qt.core.objectdefs.QMetaObject.Call.RegisterMethodArgumentMetaType) { if (_id < allMethods.length) *reinterpret_cast!(int*)(_a[0]) = -1; _id -= allMethods.length; } return _id; } extern(C++) static void qt_static_metacall(imported!"qt.core.object".QObject _o, imported!q{qt.core.objectdefs}.QMetaObject.Call _c, int _id, void **_a) { import qt.core.objectdefs; if (_c == qt.core.objectdefs.QMetaObject.Call.InvokeMetaMethod) { alias allMethods = qt.core.objectdefs.MetaObjectImpl!(typeof(this)).allMethods; import std.conv, std.traits; auto _t = static_cast!(typeof(this))(_o); //Q_UNUSED(_t) switch (_id) { mixin((){ string methodCallCases; static foreach(i; 0..allMethods.length) {{ methodCallCases ~= text("\n case ", i, ": _t.", __traits(identifier, allMethods[i]), "("); static foreach(j, P; Parameters!(allMethods[i])) { methodCallCases ~= text("*cast(Parameters!(allMethods[", i, "])[", j, "]*)(_a[", j + 1, "]), "); } methodCallCases ~= "); break;"; }} return methodCallCases; }()); default: {} } } else if (_c == qt.core.objectdefs.QMetaObject.Call.RegisterMethodArgumentMetaType) { // TODO } else if (_c == qt.core.objectdefs.QMetaObject.Call.IndexOfMethod) { alias allSignals = qt.core.objectdefs.MetaObjectImpl!(typeof(this)).allSignals; int *result = reinterpret_cast!(int *)(_a[0]); static foreach(i; 0..allSignals.length) {{ alias _t = qt.core.objectdefs.CPPMemberFunctionPointer!(typeof(this)); auto fp = &memberFunctionExternDeclaration!(allSignals[i]); qt.core.objectdefs.CPPMemberFunctionPointer!(typeof(this)) memberFunction = qt.core.objectdefs.CPPMemberFunctionPointer!(typeof(this))(fp); if (*reinterpret_cast!(_t *)(_a[1]) == memberFunction) { *result = i; return; } }} } //Q_UNUSED(_a); } } ~ QT_TR_FUNCTIONS ~ q{ private: struct QPrivateSignal {} };

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