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39
40#ifndef Q_QDOC
41
42#ifndef QOBJECT_H
43#error Do not include qobject_impl.h directly
44#endif
45
46#if 0
47#pragma qt_sync_skip_header_check
48#pragma qt_sync_stop_processing
49#endif
50
51QT_BEGIN_NAMESPACE
52
53
54namespace QtPrivate {
55 /*
56 Logic to statically generate the array of qMetaTypeId
57 ConnectionTypes<FunctionPointer<Signal>::Arguments>::types() returns an array
58 of int that is suitable for the types arguments of the connection functions.
59
60 The array only exist of all the types are declared as a metatype
61 (detected using the TypesAreDeclaredMetaType helper struct)
62 If one of the type is not declared, the function return 0 and the signal
63 cannot be used in queued connection.
64 */
65 template <typename ArgList> struct TypesAreDeclaredMetaType { enum { Value = false }; };
66 template <> struct TypesAreDeclaredMetaType<List<>> { enum { Value = true }; };
67 template <typename Arg, typename... Tail> struct TypesAreDeclaredMetaType<List<Arg, Tail...> >
68 { enum { Value = QMetaTypeId2<Arg>::Defined && TypesAreDeclaredMetaType<List<Tail...>>::Value }; };
69
70 template <typename ArgList, bool Declared = TypesAreDeclaredMetaType<ArgList>::Value > struct ConnectionTypes
71 { static const int *types() { return nullptr; } };
72 template <> struct ConnectionTypes<List<>, true>
73 { static const int *types() { return nullptr; } };
74 template <typename... Args> struct ConnectionTypes<List<Args...>, true>
75 { static const int *types() { static const int t[sizeof...(Args) + 1] = { (QtPrivate::QMetaTypeIdHelper<Args>::qt_metatype_id())..., 0 }; return t; } };
76
77 // implementation of QSlotObjectBase for which the slot is a static function
78 // Args and R are the List of arguments and the return type of the signal to which the slot is connected.
79 template<typename Func, typename Args, typename R> class QStaticSlotObject : public QSlotObjectBase
80 {
81 typedef QtPrivate::FunctionPointer<Func> FuncType;
82 Func function;
83 static void impl(int which, QSlotObjectBase *this_, QObject *r, void **a, bool *ret)
84 {
85 switch (which) {
86 case Destroy:
87 delete static_cast<QStaticSlotObject*>(this_);
88 break;
89 case Call:
90 FuncType::template call<Args, R>(static_cast<QStaticSlotObject*>(this_)->function, r, a);
91 break;
92 case Compare: // not implemented
93 case NumOperations:
94 Q_UNUSED(ret);
95 }
96 }
97 public:
98 explicit QStaticSlotObject(Func f) : QSlotObjectBase(&impl), function(f) {}
99 };
100}
101
102
103QT_END_NAMESPACE
104
105#endif
106

source code of qtbase/src/corelib/kernel/qobject_impl.h