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41
42#ifndef QPOINTER_H
43#define QPOINTER_H
44
45#include <QtCore/qobject.h>
46
47QT_BEGIN_HEADER
48
49QT_BEGIN_NAMESPACE
50
51QT_MODULE(Core)
52
53template <class T>
54class QPointer
55{
56 QObject *o;
57public:
58 inline QPointer() : o(0) {}
59 inline QPointer(T *p) : o(p)
60 { QMetaObject::addGuard(&o); }
61 inline QPointer(const QPointer<T> &p) : o(p.o)
62 { QMetaObject::addGuard(&o); }
63 inline ~QPointer()
64 { QMetaObject::removeGuard(&o); }
65 inline QPointer<T> &operator=(const QPointer<T> &p)
66 { if (this != &p) QMetaObject::changeGuard(&o, p.o); return *this; }
67 inline QPointer<T> &operator=(T* p)
68 { if (o != p) QMetaObject::changeGuard(&o, p); return *this; }
69
70 inline bool isNull() const
71 { return !o; }
72
73 inline T* operator->() const
74 { return static_cast<T*>(const_cast<QObject*>(o)); }
75 inline T& operator*() const
76 { return *static_cast<T*>(const_cast<QObject*>(o)); }
77 inline operator T*() const
78 { return static_cast<T*>(const_cast<QObject*>(o)); }
79 inline T* data() const
80 { return static_cast<T*>(const_cast<QObject*>(o)); }
81};
82
83
84#if (!defined(Q_CC_SUN) || (__SUNPRO_CC >= 0x580)) // ambiguity between const T * and T *
85
86template <class T>
87inline bool operator==(const T *o, const QPointer<T> &p)
88{ return o == p.operator->(); }
89
90template<class T>
91inline bool operator==(const QPointer<T> &p, const T *o)
92{ return p.operator->() == o; }
93
94#else
95
96template<class T>
97inline bool operator==(const void *o, const QPointer<T> &p)
98{ return o == p.operator->(); }
99
100template<class T>
101inline bool operator==(const QPointer<T> &p, const void *o)
102{ return p.operator->() == o; }
103
104#endif
105
106template <class T>
107inline bool operator==(T *o, const QPointer<T> &p)
108{ return o == p.operator->(); }
109
110template<class T>
111inline bool operator==(const QPointer<T> &p, T *o)
112{ return p.operator->() == o; }
113
114template<class T>
115inline bool operator==(const QPointer<T> &p1, const QPointer<T> &p2)
116{ return p1.operator->() == p2.operator->(); }
117
118
119#if (!defined(Q_CC_SUN) || (__SUNPRO_CC >= 0x580)) // ambiguity between const T * and T *
120
121template <class T>
122inline bool operator!=(const T *o, const QPointer<T> &p)
123{ return o != p.operator->(); }
124
125template<class T>
126inline bool operator!= (const QPointer<T> &p, const T *o)
127{ return p.operator->() != o; }
128
129#else
130
131template<class T>
132inline bool operator!= (const void *o, const QPointer<T> &p)
133{ return o != p.operator->(); }
134
135template<class T>
136inline bool operator!= (const QPointer<T> &p, const void *o)
137{ return p.operator->() != o; }
138
139#endif
140
141template <class T>
142inline bool operator!=(T *o, const QPointer<T> &p)
143{ return o != p.operator->(); }
144
145template<class T>
146inline bool operator!= (const QPointer<T> &p, T *o)
147{ return p.operator->() != o; }
148
149template<class T>
150inline bool operator!= (const QPointer<T> &p1, const QPointer<T> &p2)
151{ return p1.operator->() != p2.operator->() ; }
152
153// Make MSVC < 1400 (2005) handle "if (NULL == p)" syntax
154#if defined(Q_CC_MSVC) && (_MSC_VER < 1400)
155template<class T>
156inline bool operator== (int i, const QPointer<T> &p)
157{ Q_ASSERT(i == 0); return !i && p.isNull(); }
158
159template<class T>
160inline bool operator!= (int i, const QPointer<T> &p)
161{ Q_ASSERT(i == 0); return !i && !p.isNull(); }
162#endif
163
164QT_END_NAMESPACE
165
166QT_END_HEADER
167
168#endif // QPOINTER_H
169