text: /****************************************************************************
  **
  ** Copyright (C) 2014 Digia Plc and/or its subsidiary(-ies).
  ** Contact: http://www.qt-project.org/legal
  **
  ** This file is part of the QtDeclarative module of the Qt Toolkit.
  **
  ** $QT_BEGIN_LICENSE:LGPL21$
  ** Commercial License Usage
  ** Licensees holding valid commercial Qt licenses may use this file in
  ** accordance with the commercial license agreement provided with the
  ** Software or, alternatively, in accordance with the terms contained in
  ** a written agreement between you and Digia. For licensing terms and
  ** conditions see http://qt.digia.com/licensing. For further information
  ** use the contact form at http://qt.digia.com/contact-us.
  **
  ** GNU Lesser General Public License Usage
  ** Alternatively, this file may be used under the terms of the GNU Lesser
  ** General Public License version 2.1 or version 3 as published by the Free
  ** Software Foundation and appearing in the file LICENSE.LGPLv21 and
  ** LICENSE.LGPLv3 included in the packaging of this file. Please review the
  ** following information to ensure the GNU Lesser General Public License
  ** requirements will be met: https://www.gnu.org/licenses/lgpl.html and
  ** http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
  **
  ** In addition, as a special exception, Digia gives you certain additional
  ** rights. These rights are described in the Digia Qt LGPL Exception
  ** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
  **
  ** $QT_END_LICENSE$
  **
  ****************************************************************************/
  
  #ifndef QDECLARATIVEEXPRESSION_H
  #define QDECLARATIVEEXPRESSION_H
  
  #include <QtDeclarative/qdeclarativeerror.h>
  
  #include <QtCore/qobject.h>
  #include <QtCore/qvariant.h>
  
  QT_BEGIN_NAMESPACE
  
  QT_MODULE(Declarative)
  
  class QString;
  class QDeclarativeRefCount;
  class QDeclarativeEngine;
  class QDeclarativeContext;
  class QDeclarativeExpressionPrivate;
  class QDeclarativeContextData;
  class QScriptValue;
  class Q_DECLARATIVE_EXPORT QDeclarativeExpression : public QObject
  {
      Q_OBJECT
  public:
      QDeclarativeExpression();
      QDeclarativeExpression(QDeclarativeContext *, QObject *, const QString &, QObject * = 0);
      virtual ~QDeclarativeExpression();
  
      QDeclarativeEngine *engine() const;
      QDeclarativeContext *context() const;
  
      QString expression() const;
      void setExpression(const QString &);
  
      bool notifyOnValueChanged() const;
      void setNotifyOnValueChanged(bool);
  
      QString sourceFile() const;
      int lineNumber() const;
      void setSourceLocation(const QString &fileName, int line);
  
      QObject *scopeObject() const;
  
      bool hasError() const;
      void clearError();
      QDeclarativeError error() const;
  
      QVariant evaluate(bool *valueIsUndefined = 0);
  
  Q_SIGNALS:
      void valueChanged();
  
  protected:
      QDeclarativeExpression(QDeclarativeContextData *, QObject *, const QString &,
                             QDeclarativeExpressionPrivate &dd);
      QDeclarativeExpression(QDeclarativeContextData *, QObject *, const QScriptValue &,
                             QDeclarativeExpressionPrivate &dd);
      QDeclarativeExpression(QDeclarativeContextData *, void *, QDeclarativeRefCount *rc,
                             QObject *me, const QString &, int, QDeclarativeExpressionPrivate &dd);
  
  private:
      QDeclarativeExpression(QDeclarativeContextData *, QObject *, const QString &);
  
      Q_DISABLE_COPY(QDeclarativeExpression)
      Q_DECLARE_PRIVATE(QDeclarativeExpression)
      Q_PRIVATE_SLOT(d_func(), void _q_notify())
      friend class QDeclarativeDebugger;
      friend class QDeclarativeContext;
      friend class QDeclarativeVME;
  };
  
  QT_END_NAMESPACE
  
  #endif // QDECLARATIVEEXPRESSION_H
  
  