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39
40#include "qcommonsequencetypes_p.h"
41#include "qcommonvalues_p.h"
42#include "qemptysequence_p.h"
43#include "qinteger_p.h"
44#include "qschemanumeric_p.h"
45#include "qrangeiterator_p.h"
46
47#include "qnodecomparison_p.h"
48
49QT_BEGIN_NAMESPACE
50
51using namespace QPatternist;
52
53NodeComparison::NodeComparison(const Expression::Ptr &operand1,
54 const QXmlNodeModelIndex::DocumentOrder op,
55 const Expression::Ptr &operand2)
56 : PairContainer(operand1, operand2)
57 , m_op(op)
58{
59 Q_ASSERT(op == QXmlNodeModelIndex::Precedes ||
60 op == QXmlNodeModelIndex::Follows ||
61 op == QXmlNodeModelIndex::Is);
62}
63
64Item NodeComparison::evaluateSingleton(const DynamicContext::Ptr &context) const
65{
66 switch(evaluate(context))
67 {
68 case True:
69 return CommonValues::BooleanTrue;
70 case False:
71 return CommonValues::BooleanFalse;
72 default:
73 return Item();
74 }
75}
76
77bool NodeComparison::evaluateEBV(const DynamicContext::Ptr &context) const
78{
79 switch(evaluate(context))
80 {
81 case True:
82 return true;
83 default:
84 /* We include the empty sequence here. */
85 return false;
86 }
87}
88
89NodeComparison::Result NodeComparison::evaluate(const DynamicContext::Ptr &context) const
90{
91 const Item op1(m_operand1->evaluateSingleton(context));
92 if(!op1)
93 return Empty;
94
95 const Item op2(m_operand2->evaluateSingleton(context));
96 if(!op2)
97 return Empty;
98
99 /* We just returns an arbitrary value, since there's no order defined for nodes from different
100 * models, except for that the return value must be stable. */
101 if(op1.asNode().model() != op2.asNode().model())
102 return False;
103
104 switch(m_op)
105 {
106 case QXmlNodeModelIndex::Is:
107 return op1.asNode().is(other: op2.asNode()) ? True : False;
108 case QXmlNodeModelIndex::Precedes:
109 return op1.asNode().compareOrder(other: op2.asNode()) == QXmlNodeModelIndex::Precedes ? True : False;
110 default:
111 {
112 Q_ASSERT(m_op == QXmlNodeModelIndex::Follows);
113 return op1.asNode().compareOrder(other: op2.asNode()) == QXmlNodeModelIndex::Follows ? True : False;
114 }
115 }
116}
117
118
119SequenceType::List NodeComparison::expectedOperandTypes() const
120{
121 SequenceType::List result;
122 result.append(t: CommonSequenceTypes::ZeroOrOneNode);
123 result.append(t: CommonSequenceTypes::ZeroOrOneNode);
124 return result;
125}
126
127Expression::Ptr NodeComparison::compress(const StaticContext::Ptr &context)
128{
129 const Expression::Ptr me(PairContainer::compress(context));
130
131 if(me != this)
132 /* We're already rewritten. */
133 return me;
134
135 if(m_operand1->staticType()->cardinality().isEmpty() ||
136 m_operand2->staticType()->cardinality().isEmpty())
137 {
138 // TODO issue a warning in the @p context saying that one of the operands
139 // were empty, and that the expression always result in the empty sequence
140 // (which never is the intent, right?).
141 return EmptySequence::create(replacementFor: this, context);
142 }
143
144 return Expression::Ptr(this);
145}
146
147QString NodeComparison::displayName(const QXmlNodeModelIndex::DocumentOrder op)
148{
149 switch(op)
150 {
151 case QXmlNodeModelIndex::Is:
152 return QLatin1String("is");
153 case QXmlNodeModelIndex::Precedes:
154 return QLatin1String("<<");
155 default:
156 {
157 Q_ASSERT(op == QXmlNodeModelIndex::Follows);
158 return QLatin1String(">>");
159 }
160 }
161}
162
163SequenceType::Ptr NodeComparison::staticType() const
164{
165 if(m_operand1->staticType()->cardinality().allowsEmpty() ||
166 m_operand2->staticType()->cardinality().allowsEmpty())
167 return CommonSequenceTypes::ZeroOrOneBoolean;
168 else
169 return CommonSequenceTypes::ExactlyOneBoolean;
170}
171
172QXmlNodeModelIndex::DocumentOrder NodeComparison::operatorID() const
173{
174 return m_op;
175}
176
177ExpressionVisitorResult::Ptr NodeComparison::accept(const ExpressionVisitor::Ptr &visitor) const
178{
179 return visitor->visit(this);
180}
181
182QT_END_NAMESPACE
183

source code of qtxmlpatterns/src/xmlpatterns/expr/qnodecomparison.cpp