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39
40#ifndef QQMLNULLABLEVALUE_P_H
41#define QQMLNULLABLEVALUE_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
54QT_BEGIN_NAMESPACE
55
56template<typename T>
57struct QQmlNullableValue
58{
59 QQmlNullableValue()
60 : value(T()) {}
61 QQmlNullableValue(const QQmlNullableValue<T> &o)
62 : isNull(o.isNull), value(o.value) {}
63 QQmlNullableValue(const T &t)
64 : isNull(false), value(t) {}
65 QQmlNullableValue<T> &operator=(const T &t)
66 { isNull = false; value = t; return *this; }
67 QQmlNullableValue<T> &operator=(const QQmlNullableValue<T> &o)
68 { isNull = o.isNull; value = o.value; return *this; }
69 operator T() const { return value; }
70
71 void invalidate() { isNull = true; }
72 bool isValid() const { return !isNull; }
73 bool isNull = true;
74 T value;
75};
76
77QT_END_NAMESPACE
78
79#endif // QQMLNULLABLEVALUE_P_H
80