--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/src/xmlpatterns/expr/qforclause.cpp Mon Jan 11 14:00:40 2010 +0000
@@ -0,0 +1,200 @@
+/****************************************************************************
+**
+** Copyright (C) 2009 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.
+**
+**
+**
+**
+**
+**
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "qcommonsequencetypes_p.h"
+#include "qemptysequence_p.h"
+#include "qgenericsequencetype_p.h"
+#include "qitemmappingiterator_p.h"
+#include "qoptimizationpasses_p.h"
+#include "qsequencemappingiterator_p.h"
+
+#include "qforclause_p.h"
+
+QT_BEGIN_NAMESPACE
+
+using namespace QPatternist;
+
+ForClause::ForClause(const VariableSlotID varSlot,
+ const Expression::Ptr &bindingSequence,
+ const Expression::Ptr &returnExpression,
+ const VariableSlotID positionSlot) : PairContainer(bindingSequence, returnExpression),
+ m_varSlot(varSlot),
+ m_positionSlot(positionSlot),
+ m_allowsMany(true)
+{
+ Q_ASSERT(m_positionSlot > -2);
+}
+
+Item ForClause::mapToItem(const Item &item,
+ const DynamicContext::Ptr &context) const
+{
+ context->setRangeVariable(m_varSlot, item);
+ return m_operand2->evaluateSingleton(context);
+}
+
+Item::Iterator::Ptr ForClause::mapToSequence(const Item &item,
+ const DynamicContext::Ptr &context) const
+{
+ context->setRangeVariable(m_varSlot, item);
+ return m_operand2->evaluateSequence(context);
+}
+
+void ForClause::riggPositionalVariable(const DynamicContext::Ptr &context,
+ const Item::Iterator::Ptr &source) const
+{
+ if(m_positionSlot > -1)
+ context->setPositionIterator(m_positionSlot, source);
+}
+
+Item::Iterator::Ptr ForClause::evaluateSequence(const DynamicContext::Ptr &context) const
+{
+ const Item::Iterator::Ptr source(m_operand1->evaluateSequence(context));
+
+ riggPositionalVariable(context, source);
+
+ if(m_allowsMany)
+ {
+ return makeSequenceMappingIterator<Item>(ConstPtr(this),
+ source,
+ context);
+ }
+ else
+ {
+ return makeItemMappingIterator<Item>(ConstPtr(this),
+ source,
+ context);
+ }
+}
+
+Item ForClause::evaluateSingleton(const DynamicContext::Ptr &context) const
+{
+ return evaluateSequence(context)->next();
+}
+
+void ForClause::evaluateToSequenceReceiver(const DynamicContext::Ptr &context) const
+{
+ Item::Iterator::Ptr it;
+ const Item::Iterator::Ptr source(m_operand1->evaluateSequence(context));
+
+ riggPositionalVariable(context, source);
+
+ Item next(source->next());
+
+ while(next)
+ {
+ context->setRangeVariable(m_varSlot, next);
+ m_operand2->evaluateToSequenceReceiver(context);
+ next = source->next();
+ }
+}
+
+Expression::Ptr ForClause::typeCheck(const StaticContext::Ptr &context,
+ const SequenceType::Ptr &reqType)
+{
+ const Expression::Ptr me(PairContainer::typeCheck(context, reqType));
+ const Cardinality card(m_operand1->staticType()->cardinality());
+
+ /* If our source is empty we will always evaluate to the empty sequence, so rewrite. */
+ if(card.isEmpty())
+ return EmptySequence::create(this, context);
+ else
+ return me;
+
+ /* This breaks because the variable references haven't rewritten themselves, so
+ * they dangle. When this is fixed, evaluateSingleton can be removed. */
+ /*
+ else if(card->allowsMany())
+ return me;
+ else
+ return m_operand2;
+ */
+}
+
+Expression::Ptr ForClause::compress(const StaticContext::Ptr &context)
+{
+ const Expression::Ptr me(PairContainer::compress(context));
+ if(me != this)
+ return me;
+
+ /* This is done after calling PairContainer::typeCheck(). The advantage of this is that
+ * m_allowsMany is updated according to what the operand says after it has compressed. However,
+ * if it was initialized to false(as it once was..), ForClause::evaluateSequence()
+ * would potentially have been called by PairContainer::compress(), and it would have
+ * used an unsafe branch. */
+ m_allowsMany = m_operand2->staticType()->cardinality().allowsMany();
+
+ return me;
+}
+
+SequenceType::Ptr ForClause::staticType() const
+{
+ const SequenceType::Ptr returnType(m_operand2->staticType());
+
+ return makeGenericSequenceType(returnType->itemType(),
+ m_operand1->staticType()->cardinality()
+ * /* multiply operator */
+ returnType->cardinality());
+}
+
+SequenceType::List ForClause::expectedOperandTypes() const
+{
+ SequenceType::List result;
+ result.append(CommonSequenceTypes::ZeroOrMoreItems);
+ result.append(CommonSequenceTypes::ZeroOrMoreItems);
+ return result;
+}
+
+ExpressionVisitorResult::Ptr ForClause::accept(const ExpressionVisitor::Ptr &visitor) const
+{
+ return visitor->visit(this);
+}
+
+OptimizationPass::List ForClause::optimizationPasses() const
+{
+ return OptimizationPasses::forPasses;
+}
+
+Expression::ID ForClause::id() const
+{
+ return IDForClause;
+}
+
+QT_END_NAMESPACE