How to get QScriptValue property changes

I have program which use global properties in QScriptEngine.
There is the class of variable used in script code:

Code:

---

#ifndef VARIABLECONFIGURATION_H
#define VARIABLECONFIGURATION_H
 
#include <QMetaType>
 
class VariableConfiguration : public QObject
{
    Q_OBJECT
private:
    int _value;
public:
    explicit VariableConfiguration(QObject *parent = 0);
public slots:
    void setValue(int value);
    int value() const;
signals:
    void valueChanged(int value);
};
 
Q_DECLARE_METATYPE(VariableConfiguration*)
 
#endif // VARIABLECONFIGURATION_H

---

Code:

---

#include "VariableConfiguration.h"
 
VariableConfiguration::VariableConfiguration(QObject *parent) :
    QObject(parent), _value(0) {
}
 
void VariableConfiguration::setValue(int value) {
    if (_value != value) {
        _value = value;
        emit valueChanged(_value);
    }
}
 
int VariableConfiguration::value() const {
    return _value;
}

---

In main code:

Code:

---

_scriptEngine = new QScriptEngine(this);
qScriptRegisterMetaType(_scriptEngine, toScriptValue, fromScriptValue);
 
VariableConfiguration* var = new VariableConfiguration(this);
connect(var, SIGNAL(valueChanged(int)), this, SLOT(variableValueChanged(int)));
 
_scriptEngine->globalObject().setProperty("intVar", toScriptValue(_scriptEngine, var));

---

For example, I need to run script code:
intVar = 10;
How can I do that variable emit valueChanged signal when property value changed while script running?
P.S. Now I can use my variable class as intVar.setValue(10); but need intVar = 10;

Thank you.