/**************************************************************************** ** ** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies). ** 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_DynamicContext_H #define Patternist_DynamicContext_H #include "qautoptr_p.h" #include "qcachecells_p.h" #include "qexternalvariableloader_p.h" #include "qitem_p.h" #include "qnamepool_p.h" #include "qnodebuilder_p.h" #include "qprimitives_p.h" #include "qreportcontext_p.h" #include "qresourceloader_p.h" QT_BEGIN_HEADER QT_BEGIN_NAMESPACE class QDateTime; template class QVector; namespace QPatternist { class DayTimeDuration; class Expression; class TemplateMode; /** * @short Carries information and facilities used at runtime, and hence * provides a state for that stage in a thread-safe manner. * * @see XQuery * 1.0: An XML Query Language, 2.1.2 Dynamic Context * @see XQuery * 1.0: An XML Query Language, 2.2.3.2 Dynamic Evaluation Phase * @author Frans Englich */ class DynamicContext : public ReportContext { public: /** * @short Carries template parameters at runtime. * * The key is the name of the parameter, and the value the Expression * which supplies the value. */ typedef QHash > TemplateParameterHash; typedef QExplicitlySharedDataPointer Ptr; virtual ~DynamicContext() { } /** * This function intentionally returns by reference. * * @see globalItemCacheCell() */ virtual ItemCacheCell &itemCacheCell(const VariableSlotID slot) = 0; /** * This function intentionally returns by reference. * * @see globalItemSequenceCacheCells */ virtual ItemSequenceCacheCell::Vector &itemSequenceCacheCells(const VariableSlotID slot) = 0; virtual xsInteger contextPosition() const = 0; virtual Item contextItem() const = 0; virtual xsInteger contextSize() = 0; virtual void setRangeVariable(const VariableSlotID slot, const Item &newValue) = 0; virtual Item rangeVariable(const VariableSlotID slot) const = 0; virtual void setExpressionVariable(const VariableSlotID slot, const QExplicitlySharedDataPointer &newValue) = 0; virtual QExplicitlySharedDataPointer expressionVariable(const VariableSlotID slot) const = 0; virtual Item::Iterator::Ptr positionIterator(const VariableSlotID slot) const = 0; virtual void setPositionIterator(const VariableSlotID slot, const Item::Iterator::Ptr &newValue) = 0; virtual void setFocusIterator(const Item::Iterator::Ptr &it) = 0; virtual Item::Iterator::Ptr focusIterator() const = 0; virtual QExplicitlySharedDataPointer implicitTimezone() const = 0; virtual QDateTime currentDateTime() const = 0; virtual QAbstractXmlReceiver *outputReceiver() const = 0; virtual NodeBuilder::Ptr nodeBuilder(const QUrl &baseURI) const = 0; virtual ResourceLoader::Ptr resourceLoader() const = 0; virtual ExternalVariableLoader::Ptr externalVariableLoader() const = 0; virtual NamePool::Ptr namePool() const = 0; /** * @short Returns the item that @c fn:current() returns. * * Hence, this is not the focus, and very different from the focus. * * @see CurrentItemStore * @see CurrentFN */ virtual Item currentItem() const = 0; DynamicContext::Ptr createFocus(); DynamicContext::Ptr createStack(); DynamicContext::Ptr createReceiverContext(QAbstractXmlReceiver *const receiver); /** * Whenever a tree gets built, this function is called. DynamicContext * has the responsibility of keeping a copy of @p nm, such that it * doesn't go out of scope, since no one else will reference @p nm. * * I think this is currently only used for temporary node trees. In * other cases they are stored in the ExternalResourceLoader. * * The caller guarantees that @p nm is not @c null. */ virtual void addNodeModel(const QAbstractXmlNodeModel::Ptr &nm) = 0; /** * Same as itemCacheCell(), but is only used for global varibles. This * is needed because sometimes stack frames needs to be created for * other kinds of variables(such as in the case of user function * calls), while the global variable(s) needs to continue to use the * same cache, instead of one for each new stack frame, typically an * instance of StackContextBase. * * This has two effects: * * - It's an optimization. Instead of that a global variable gets evaluated each * time a user function is called, think recursive functions, it's done * only once. * - Query stability, hence affects things like node identity and * therefore conformance. Hence affects for instance what nodes a query * returns, since node identity affect node deduplication. */ virtual ItemCacheCell &globalItemCacheCell(const VariableSlotID slot) = 0; /** * @short When a template is called, this member carries the template * parameters. * * Hence this is similar to the other variable stack functions such as * rangeVariable() and expressionVariable(), the difference being that * the order of template parameters as well as its arguments can appear * in arbitrary order. Hence the name is used to make the order * insignificant. */ virtual TemplateParameterHash &templateParameterStore() = 0; /** * Same as itemSequenceCacheCells() but applies only for global * variables. * * @see globalItemCacheCell() */ virtual ItemSequenceCacheCell::Vector &globalItemSequenceCacheCells(const VariableSlotID slot) = 0; /** * @short Returns the previous DynamicContext. If this context is the * top-level one, @c null is returned. */ virtual DynamicContext::Ptr previousContext() const = 0; /** * @short Returns the current template mode that is in effect. * * If @c null is returned, it means that the default mode should be * used as the current mode. */ virtual QExplicitlySharedDataPointer currentTemplateMode() const = 0; }; } QT_END_NAMESPACE QT_END_HEADER #endif