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39
40#ifndef QLAZILYALLOCATED_P_H
41#define QLAZILYALLOCATED_P_H
42
43//
44// W A R N I N G
45// -------------
46//
47// This file is not part of the Qt API. It exists purely as an
48// implementation detail. This header file may change from version to
49// version without notice, or even be removed.
50//
51// We mean it.
52//
53
54#include <QtCore/qglobal.h>
55
56#include <private/qflagpointer_p.h>
57
58QT_BEGIN_NAMESPACE
59
60template<typename T>
61class QLazilyAllocated {
62public:
63 inline QLazilyAllocated();
64 inline ~QLazilyAllocated();
65
66 inline bool isAllocated() const;
67
68 inline T *operator->() const;
69
70 inline T &value();
71 inline const T &value() const;
72
73 inline bool flag() const;
74 inline void setFlag();
75 inline void clearFlag();
76 inline void setFlagValue(bool);
77private:
78 mutable QFlagPointer<T> d;
79};
80
81template<typename T>
82QLazilyAllocated<T>::QLazilyAllocated()
83{
84}
85
86template<typename T>
87QLazilyAllocated<T>::~QLazilyAllocated()
88{
89 delete *d;
90}
91
92template<typename T>
93bool QLazilyAllocated<T>::isAllocated() const
94{
95 return !d.isNull();
96}
97
98template<typename T>
99T &QLazilyAllocated<T>::value()
100{
101 if (d.isNull()) d = new T;
102 return *(*d);
103}
104
105template<typename T>
106const T &QLazilyAllocated<T>::value() const
107{
108 if (d.isNull()) d = new T;
109 return *(*d);
110}
111
112template<typename T>
113T *QLazilyAllocated<T>::operator->() const
114{
115 return *d;
116}
117
118template<typename T>
119bool QLazilyAllocated<T>::flag() const
120{
121 return d.flag();
122}
123
124template<typename T>
125void QLazilyAllocated<T>::setFlag()
126{
127 d.setFlag();
128}
129
130template<typename T>
131void QLazilyAllocated<T>::clearFlag()
132{
133 d.clearFlag();
134}
135
136template<typename T>
137void QLazilyAllocated<T>::setFlagValue(bool v)
138{
139 d.setFlagValue(v);
140}
141
142QT_END_NAMESPACE
143
144#endif // QLAZILYALLOCATED_P_H
145

source code of qtdeclarative/src/qml/qml/ftw/qlazilyallocated_p.h