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Diffstat (limited to 'src/xmlpatterns/iterators/qdistinctiterator_p.h')
| -rw-r--r-- | src/xmlpatterns/iterators/qdistinctiterator_p.h | 128 |
1 files changed, 128 insertions, 0 deletions
diff --git a/src/xmlpatterns/iterators/qdistinctiterator_p.h b/src/xmlpatterns/iterators/qdistinctiterator_p.h new file mode 100644 index 0000000..70d7e3a --- /dev/null +++ b/src/xmlpatterns/iterators/qdistinctiterator_p.h @@ -0,0 +1,128 @@ +/**************************************************************************** +** +** 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. +** +** $QT_BEGIN_LICENSE:LGPL$ +** No Commercial Usage +** This file contains pre-release code and may not be distributed. +** You may use this file in accordance with the terms and conditions +** contained in the Technology Preview License Agreement accompanying +** this package. +** +** 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 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. +** +** If you have questions regarding the use of this file, please contact +** Nokia at qt-info@nokia.com. +** +** +** +** +** +** +** +** +** $QT_END_LICENSE$ +** +****************************************************************************/ + +// +// 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_DistinctIterator_H +#define Patternist_DistinctIterator_H + +#include <QList> + +#include "qexpression_p.h" +#include "qitem_p.h" +#include "qatomiccomparator_p.h" +#include "qcomparisonplatform_p.h" +#include "qsourcelocationreflection_p.h" + +QT_BEGIN_HEADER + +QT_BEGIN_NAMESPACE + +namespace QPatternist +{ + + /** + * @short Filters another sequence by removing duplicates such that the items are unique. + * + * DistinctIterator takes an input sequence, and returns a sequence where each + * item is unique. Thus, DistinctIterator removes the duplicates of items + * in a sequence. DistinctIterator is central in the implementation of the + * <tt>fn:distinct-values()</tt> function. + * + * @see <a href="http://www.w3.org/TR/xpath-functions/#func-distinct-values">XQuery 1.0 + * and XPath 2.0 Functions and Operators, 15.1.6 fn:distinct-values</a> + * @author Frans Englich <frans.englich@nokia.com> + * @ingroup Patternist_iterators + */ + class DistinctIterator : public Item::Iterator + , public ComparisonPlatform<DistinctIterator, false> + , public SourceLocationReflection + { + public: + /** + * Creates a DistinctIterator. + * @param comp the AtomicComparator to be used for comparing values. This may be @c null, + * meaning the IndexOfIterator iterator will dynamically determine what comparator to use + * @param seq the sequence whose duplicates should be filtered out + * @param context the usual context, used for error reporting and by AtomicComparators. + * @param expression the Expression that this DistinctIterator is + * evaluating for. It is used for error reporting, via + * actualReflection(). + */ + DistinctIterator(const Item::Iterator::Ptr &seq, + const AtomicComparator::Ptr &comp, + const Expression::ConstPtr &expression, + const DynamicContext::Ptr &context); + + virtual Item next(); + virtual Item current() const; + virtual xsInteger position() const; + virtual Item::Iterator::Ptr copy() const; + virtual const SourceLocationReflection *actualReflection() const; + + inline AtomicComparator::Operator operatorID() const + { + return AtomicComparator::OperatorEqual; + } + + private: + const Item::Iterator::Ptr m_seq; + const DynamicContext::Ptr m_context; + const Expression::ConstPtr m_expr; + Item m_current; + xsInteger m_position; + Item::List m_processed; + }; +} + +QT_END_NAMESPACE + +QT_END_HEADER + +#endif |