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46 // This file is not part of the Qt API. It exists purely as an
47 // implementation detail. This header file may change from version to
48 // version without notice, or even be removed.
52 #ifndef QPatternist_ReferenceCountedValue_p_h
53 #define QPatternist_ReferenceCountedValue_p_h
61 \class ReferenceCountedValue
64 \brief A template class that reference counts a value.
66 This class is useful when an instance needs to have ownership semantics
67 as if it was value based. A typical examples is a QObject pointer, which
68 doesn't have a single owner.
70 This is achieved through storing a copy of the object as
71 a member inside ReferenceCountedValue, which never is copied. It will
72 stay in scope until the last reference to the ReferenceCountedValue instance
73 is removed, and subsequently ReferenceCountedValue is deleted and hence also
74 the contained value. One should use ReferenceCountedValue by passing around
75 copies of Ptr, which is a typedef for the QExplicitlySharedDataPointer
79 class ReferenceCountedValue : public QSharedData
82 typedef QExplicitlySharedDataPointer<ReferenceCountedValue<T> > Ptr;
84 inline ReferenceCountedValue(T *const v) : value(v)
88 inline ~ReferenceCountedValue()
96 Disabled, no implementation provided.
98 inline ReferenceCountedValue();
99 Q_DISABLE_COPY(ReferenceCountedValue)