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5 ** Contact: Nokia Corporation (qt-info@nokia.com)
7 ** This file is part of the QtXmlPatterns module of the Qt Toolkit.
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42 #include "qcommonsequencetypes_p.h"
43 #include "qcommonvalues_p.h"
44 #include "qemptysequence_p.h"
45 #include "qinteger_p.h"
46 #include "qschemanumeric_p.h"
47 #include "qrangeiterator_p.h"
49 #include "qnodecomparison_p.h"
53 using namespace QPatternist;
55 NodeComparison::NodeComparison(const Expression::Ptr &operand1,
56 const QXmlNodeModelIndex::DocumentOrder op,
57 const Expression::Ptr &operand2)
58 : PairContainer(operand1, operand2)
61 Q_ASSERT(op == QXmlNodeModelIndex::Precedes ||
62 op == QXmlNodeModelIndex::Follows ||
63 op == QXmlNodeModelIndex::Is);
66 Item NodeComparison::evaluateSingleton(const DynamicContext::Ptr &context) const
68 switch(evaluate(context))
71 return CommonValues::BooleanTrue;
73 return CommonValues::BooleanFalse;
79 bool NodeComparison::evaluateEBV(const DynamicContext::Ptr &context) const
81 switch(evaluate(context))
86 /* We include the empty sequence here. */
91 NodeComparison::Result NodeComparison::evaluate(const DynamicContext::Ptr &context) const
93 const Item op1(m_operand1->evaluateSingleton(context));
97 const Item op2(m_operand2->evaluateSingleton(context));
101 /* We just returns an arbitrary value, since there's no order defined for nodes from different
102 * models, except for that the return value must be stable. */
103 if(op1.asNode().model() != op2.asNode().model())
108 case QXmlNodeModelIndex::Is:
109 return op1.asNode().is(op2.asNode()) ? True : False;
110 case QXmlNodeModelIndex::Precedes:
111 return op1.asNode().compareOrder(op2.asNode()) == QXmlNodeModelIndex::Precedes ? True : False;
114 Q_ASSERT(m_op == QXmlNodeModelIndex::Follows);
115 return op1.asNode().compareOrder(op2.asNode()) == QXmlNodeModelIndex::Follows ? True : False;
121 SequenceType::List NodeComparison::expectedOperandTypes() const
123 SequenceType::List result;
124 result.append(CommonSequenceTypes::ZeroOrOneNode);
125 result.append(CommonSequenceTypes::ZeroOrOneNode);
129 Expression::Ptr NodeComparison::compress(const StaticContext::Ptr &context)
131 const Expression::Ptr me(PairContainer::compress(context));
134 /* We're already rewritten. */
137 if(m_operand1->staticType()->cardinality().isEmpty() ||
138 m_operand2->staticType()->cardinality().isEmpty())
140 // TODO issue a warning in the @p context saying that one of the operands
141 // were empty, and that the expression always result in the empty sequence
142 // (which never is the intent, right?).
143 return EmptySequence::create(this, context);
146 return Expression::Ptr(this);
149 QString NodeComparison::displayName(const QXmlNodeModelIndex::DocumentOrder op)
153 case QXmlNodeModelIndex::Is:
154 return QLatin1String("is");
155 case QXmlNodeModelIndex::Precedes:
156 return QLatin1String("<<");
159 Q_ASSERT(op == QXmlNodeModelIndex::Follows);
160 return QLatin1String(">>");
165 SequenceType::Ptr NodeComparison::staticType() const
167 if(m_operand1->staticType()->cardinality().allowsEmpty() ||
168 m_operand2->staticType()->cardinality().allowsEmpty())
169 return CommonSequenceTypes::ZeroOrOneBoolean;
171 return CommonSequenceTypes::ExactlyOneBoolean;
174 QXmlNodeModelIndex::DocumentOrder NodeComparison::operatorID() const
179 ExpressionVisitorResult::Ptr NodeComparison::accept(const ExpressionVisitor::Ptr &visitor) const
181 return visitor->visit(this);