/**************************************************************************** | |
** | |
** Copyright (C) 2011 Nokia Corporation and/or its subsidiary(-ies). | |
** All rights reserved. | |
** Contact: Nokia Corporation (qt-info@nokia.com) | |
** | |
** This file is part of the QtXmlPatterns module of the Qt Toolkit. | |
** | |
** $QT_BEGIN_LICENSE:LGPL$ | |
** GNU Lesser General Public License Usage | |
** This file may be used under the terms of the GNU Lesser General Public | |
** License version 2.1 as published by the Free Software Foundation and | |
** appearing in the file LICENSE.LGPL included in the packaging of this | |
** file. Please review the following information to ensure the GNU Lesser | |
** General Public License version 2.1 requirements will be met: | |
** http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html. | |
** | |
** In addition, as a special exception, Nokia gives you certain additional | |
** rights. These rights are described in the Nokia Qt LGPL Exception | |
** version 1.1, included in the file LGPL_EXCEPTION.txt in this package. | |
** | |
** GNU General Public License Usage | |
** Alternatively, this file may be used under the terms of the GNU General | |
** Public License version 3.0 as published by the Free Software Foundation | |
** and appearing in the file LICENSE.GPL included in the packaging of this | |
** file. Please review the following information to ensure the GNU General | |
** Public License version 3.0 requirements will be met: | |
** http://www.gnu.org/copyleft/gpl.html. | |
** | |
** Other Usage | |
** Alternatively, this file may be used in accordance with the terms and | |
** conditions contained in a signed written agreement between you and Nokia. | |
** | |
** | |
** | |
** | |
** | |
** $QT_END_LICENSE$ | |
** | |
****************************************************************************/ | |
// | |
// 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. | |
#ifndef Patternist_ExpressionSequence_H | |
#define Patternist_ExpressionSequence_H | |
#include "qunlimitedcontainer_p.h" | |
QT_BEGIN_HEADER | |
QT_BEGIN_NAMESPACE | |
namespace QPatternist | |
{ | |
/** | |
* @short Implements the comma(",") operator, the sequence constructor. | |
* | |
* For example, the expression <tt>alpha, beta</tt> evaluates to a sequence | |
* containing the items the nodetest @c alpha evaluates to, concatenated | |
* with the items the nodetest @c beta evaluates to. | |
* | |
* @see <a href="http://www.w3.org/TR/xpath20/#construct_seq">XML Path Language | |
* (XPath) 2.0, 3.3.1 Constructing Sequences</a> | |
* @author Frans Englich <frans.englich@nokia.com> | |
* @ingroup Patternist_expressions | |
*/ | |
class ExpressionSequence : public UnlimitedContainer | |
{ | |
public: | |
/** | |
* Creates an ExpressionSequence with the operands @p operands. @p operands | |
* must contain two or more Expression instances. | |
*/ | |
ExpressionSequence(const Expression::List &operands); | |
virtual Item::Iterator::Ptr evaluateSequence(const DynamicContext::Ptr &) const; | |
/** | |
* Forwards the call to its children. | |
*/ | |
virtual void evaluateToSequenceReceiver(const DynamicContext::Ptr &context) const; | |
virtual SequenceType::List expectedOperandTypes() const; | |
virtual SequenceType::Ptr staticType() const; | |
/** | |
* Removes any empty sequences, typically "()", from its list of children. If | |
* after that rewrite has no children, it rewrites itself to the CommonValues::empty; | |
* if it has only one, it rewrites to the child. | |
* | |
* This optimization is not very usable by itself, but potentially becomes effective after other | |
* optimizations have rewritten themselves into empty sequences. Thus, | |
* saving memory consumption and runtime overhead. | |
*/ | |
virtual Expression::Ptr compress(const StaticContext::Ptr &context); | |
inline Item::Iterator::Ptr mapToSequence(const Expression::Ptr &, | |
const DynamicContext::Ptr &) const; | |
virtual Expression::Ptr typeCheck(const StaticContext::Ptr &context, | |
const SequenceType::Ptr &reqType); | |
/** | |
* @returns Expression::DisableElimination, plus the union | |
* of all this ExpressionSequence's children's properties. If any child | |
* does not have IsEvaluated, it is removed from the result. | |
*/ | |
virtual Expression::Properties properties() const; | |
virtual ExpressionVisitorResult::Ptr accept(const ExpressionVisitor::Ptr &visitor) const; | |
virtual ID id() const; | |
private: | |
typedef QExplicitlySharedDataPointer<const ExpressionSequence> ConstPtr; | |
}; | |
} | |
QT_END_NAMESPACE | |
QT_END_HEADER | |
#endif |