Qt 4.8
qcastableas.cpp
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41 
42 #include "qatomictype_p.h"
43 #include "qitem_p.h"
44 #include "qboolean_p.h"
45 #include "qbuiltintypes_p.h"
46 #include "qcommonsequencetypes_p.h"
47 #include "qcommonvalues_p.h"
48 #include "qliteral_p.h"
49 
50 #include "qcastableas_p.h"
51 
53 
54 using namespace QPatternist;
55 
57  const SequenceType::Ptr &tType) : SingleContainer(operand),
58  m_targetType(tType)
59 {
60  Q_ASSERT(tType);
61  Q_ASSERT(!tType->cardinality().allowsMany());
62  Q_ASSERT(tType->itemType()->isAtomicType());
63 }
64 
65 bool CastableAs::evaluateEBV(const DynamicContext::Ptr &context) const
66 {
67  Item item;
68 
70  {
72  item = it->next();
73 
74  if(it->next())
75  return false;
76  }
77  else
78  item = m_operand->evaluateSingleton(context);
79 
80  if(item)
81  return !cast(item, context).as<AtomicValue>()->hasError();
82  else
84 }
85 
87 {
88  const Expression::Ptr me(SingleContainer::compress(context));
89 
90  if(me != this) /* We already managed to const fold, how convenient. */
91  return me;
92 
94 
95  const SequenceType::Ptr opType(m_operand->staticType());
96 
97  /* Casting to these always succeeds, assuming the cardinality also matches,
98  * although the cardinality can fail. */
99  if(( *t == *BuiltinTypes::xsString
101  || *t == *opType->itemType())
102  &&(m_targetType->cardinality().isMatch(opType->cardinality())))
103  {
104  return wrapLiteral(CommonValues::BooleanTrue, context, this);
105  }
106  else
107  return me;
108 }
109 
111  const SequenceType::Ptr &reqType)
112 {
113  checkTargetType(context);
114  const Expression::Ptr me(SingleContainer::typeCheck(context, reqType));
115 
116  return me;
117  if(BuiltinTypes::xsQName->xdtTypeMatches(m_targetType->itemType()))
118  {
119  const SequenceType::Ptr seqt(m_operand->staticType());
120  /* We can cast a string literal, an xs:QName value, and an
121  * empty sequence(if empty is allowed), to xs:QName. */
122  if(m_operand->is(IDStringValue) ||
123  BuiltinTypes::xsQName->xdtTypeMatches(seqt->itemType()) ||
124  (*seqt->itemType() == *CommonSequenceTypes::Empty && m_targetType->cardinality().allowsEmpty()))
125  {
126  return wrapLiteral(CommonValues::BooleanTrue, context, this)->typeCheck(context, reqType);
127  }
128  else
129  return wrapLiteral(CommonValues::BooleanFalse, context, this)->typeCheck(context, reqType);
130  }
131  else
132  {
133  /* Let the CastingPlatform look up its AtomicCaster. */
135 
136  return me;
137  }
138 }
139 
141 {
142  SequenceType::List result;
144  return result;
145 }
146 
148 {
150 }
151 
153 {
154  return visitor->visit(this);
155 }
156 
Item cast(const Item &sourceValue, const ReportContext::Ptr &context) const
#define QT_END_NAMESPACE
This macro expands to.
Definition: qglobal.h:90
virtual ExpressionVisitorResult::Ptr accept(const ExpressionVisitor::Ptr &visitor) const
virtual SequenceType::List expectedOperandTypes() const
static const AtomicValue::Ptr BooleanTrue
virtual bool evaluateEBV(const DynamicContext::Ptr &) const
Definition: qcastableas.cpp:65
#define it(className, varName)
Due to strong interdependencies, this file contains the definitions for the classes Item...
virtual Expression::Ptr compress(const StaticContext::Ptr &context)
Definition: qcastableas.cpp:86
virtual Expression::Ptr typeCheck(const StaticContext::Ptr &context, const SequenceType::Ptr &reqType)
Definition: qexpression.cpp:70
#define Q_ASSERT(cond)
Definition: qglobal.h:1823
virtual Expression::Ptr compress(const StaticContext::Ptr &context)
static const AtomicType::Ptr xsString
void append(const T &t)
Inserts value at the end of the list.
Definition: qlist.h:507
#define QT_BEGIN_NAMESPACE
This macro expands to.
Definition: qglobal.h:89
virtual Expression::Ptr typeCheck(const StaticContext::Ptr &context, const SequenceType::Ptr &reqType)
virtual SequenceType::Ptr staticType() const
Base class for all classes representing atomic values.
Definition: qitem_p.h:118
The namespace for the internal API of QtXmlPatterns.
bool prepareCasting(const ReportContext::Ptr &context, const ItemType::Ptr &sourceType)
virtual Cardinality cardinality() const =0
static const AtomicType::Ptr xsUntypedAtomic
static const SequenceType::Ptr ExactlyOneBoolean
virtual SequenceType::Ptr staticType() const =0
const SequenceType::Ptr m_targetType
static const EmptySequenceType::Ptr Empty
Represents an item in the XPath 2.0 Data Model.
Definition: qitem_p.h:182
static const AtomicType::Ptr xsQName
virtual bool isAtomicType() const =0
CastableAs(const Expression::Ptr &operand, const SequenceType::Ptr &targetType)
Definition: qcastableas.cpp:56
void checkTargetType(const ReportContext::Ptr &context) const
virtual ItemType::Ptr itemType() const =0
bool isMatch(const Cardinality &other) const
TCastTarget * as() const
Definition: qitem_p.h:278
static const SequenceType::Ptr ZeroOrMoreAtomicTypes
static const AtomicValue::Ptr BooleanFalse
bool is(const ID id) const
virtual Item evaluateSingleton(const DynamicContext::Ptr &context) const
The QList class is a template class that provides lists.
Definition: qdatastream.h:62
virtual Item::Iterator::Ptr evaluateSequence(const DynamicContext::Ptr &context) const
Base class for expressions that has exactly one operand.