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#ifndef QDECLARATIVEEXPRESSION_P_H

#define QDECLARATIVEEXPRESSION_P_H

//

//  W A R N I N G

//  -------------

//

// This file is not part of the Qt API.  It exists purely as an

// implementation detail.  This header file may change from version to

// version without notice, or even be removed.

//

// We mean it.

//

#include "qdeclarativeexpression.h"

#include "private/qdeclarativeengine_p.h"

#include "private/qdeclarativeguard_p.h"

#include <QtScript/qscriptvalue.h>

QT_BEGIN_NAMESPACE

class QDeclarativeAbstractExpression

{

public:

    QDeclarativeAbstractExpression();

    virtual ~QDeclarativeAbstractExpression();

    bool isValid() const;

    QDeclarativeContextData *context() const;

    void setContext(QDeclarativeContextData *);

    virtual void refresh();

private:

    friend class QDeclarativeContext;

    friend class QDeclarativeContextData;

    friend class QDeclarativeContextPrivate;

    QDeclarativeContextData *m_context;

    QDeclarativeAbstractExpression **m_prevExpression;

    QDeclarativeAbstractExpression  *m_nextExpression;

};

class QDeclarativeDelayedError 

{

public:

    inline QDeclarativeDelayedError() : nextError(0), prevError(0) {}

    inline ~QDeclarativeDelayedError() { removeError(); }

    QDeclarativeError error;

    bool addError(QDeclarativeEnginePrivate *);

    inline void removeError() {

        if (!prevError) return;

        if (nextError) nextError->prevError = prevError;

        *prevError = nextError;

        nextError = 0;

        prevError = 0;

    }

private:

    QDeclarativeDelayedError  *nextError;

    QDeclarativeDelayedError **prevError;

};

class QDeclarativeQtScriptExpression : public QDeclarativeAbstractExpression, 

                                       public QDeclarativeDelayedError

{

public:

    enum Mode { SharedContext, ExplicitContext };

    QDeclarativeQtScriptExpression();

    virtual ~QDeclarativeQtScriptExpression();

    QDeclarativeRefCount *dataRef;

    QString expression;

    Mode expressionFunctionMode;

    QScriptValue expressionFunction;

    QScriptValue expressionContext; // Only used in ExplicitContext

    QObject *scopeObject;           // Only used in SharedContext

    bool notifyOnValueChange() const;

    void setNotifyOnValueChange(bool);

    void resetNotifyOnChange();

    void setNotifyObject(QObject *, int );

    QScriptValue scriptValue(QObject *secondaryScope, bool *isUndefined);

    class DeleteWatcher {

    public:

        inline DeleteWatcher(QDeclarativeQtScriptExpression *data);

        inline ~DeleteWatcher();

        inline bool wasDeleted() const;

    private:

        bool *m_wasDeleted;

        bool m_wasDeletedStorage;

        QDeclarativeQtScriptExpression *m_d;

    };

private:

    void clearGuards();

    QScriptValue eval(QObject *secondaryScope, bool *isUndefined);

    void updateGuards(const QPODVector<QDeclarativeEnginePrivate::CapturedProperty> &properties);

    bool trackChange;

    QDeclarativeNotifierEndpoint *guardList;

    int guardListLength;

    QObject *guardObject;

    int guardObjectNotifyIndex;

    bool *deleted;

};

class QDeclarativeExpression;

class QString;

class QDeclarativeExpressionPrivate : public QObjectPrivate, public QDeclarativeQtScriptExpression

{

    Q_DECLARE_PUBLIC(QDeclarativeExpression)

public:

    QDeclarativeExpressionPrivate();

    ~QDeclarativeExpressionPrivate();

    void init(QDeclarativeContextData *, const QString &, QObject *);

    void init(QDeclarativeContextData *, void *, QDeclarativeRefCount *, QObject *, const QString &, int);

    QVariant value(QObject *secondaryScope = 0, bool *isUndefined = 0);

    QScriptValue scriptValue(QObject *secondaryScope = 0, bool *isUndefined = 0);

    static QDeclarativeExpressionPrivate *get(QDeclarativeExpression *expr) {

        return static_cast<QDeclarativeExpressionPrivate *>(QObjectPrivate::get(expr));

    }

    static QDeclarativeExpression *get(QDeclarativeExpressionPrivate *expr) {

        return expr->q_func();

    }

    void _q_notify();

    virtual void emitValueChanged();

    static void exceptionToError(QScriptEngine *, QDeclarativeError &);

    static QScriptValue evalInObjectScope(QDeclarativeContextData *, QObject *, const QString &, const QString &,

                                          int, QScriptValue *);

    static QScriptValue evalInObjectScope(QDeclarativeContextData *, QObject *, const QScriptProgram &, 

                                          QScriptValue *);

    bool expressionFunctionValid:1;

    QString url; // This is a QString for a reason.  QUrls are slooooooow...

    int line;

};

QDeclarativeQtScriptExpression::DeleteWatcher::DeleteWatcher(QDeclarativeQtScriptExpression *data)

: m_wasDeletedStorage(false), m_d(data) 

{

    if (!m_d->deleted) 

        m_d->deleted = &m_wasDeletedStorage; 

    m_wasDeleted = m_d->deleted;

}

QDeclarativeQtScriptExpression::DeleteWatcher::~DeleteWatcher() 

{

    if (false == *m_wasDeleted && m_wasDeleted == m_d->deleted)

        m_d->deleted = 0;

}

bool QDeclarativeQtScriptExpression::DeleteWatcher::wasDeleted() const 

{ 

    return *m_wasDeleted; 

}

QT_END_NAMESPACE

#endif // QDECLARATIVEEXPRESSION_P_H