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     7 ** This file is part of the QtXmlPatterns module of the Qt Toolkit.

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    41 

    42 #include "qitem_p.h"

    43 #include "qboolean_p.h"

    44 #include "qbuiltintypes_p.h"

    45 #include "qcommonsequencetypes_p.h"

    46 #include "qemptysequence_p.h"

    47 #include "qoptimizationpasses_p.h"

    48 

    49 #include "qvaluecomparison_p.h"

    50 

    51 QT_BEGIN_NAMESPACE

    52 

    53 using namespace QPatternist;

    54 

    55 ValueComparison::ValueComparison(const Expression::Ptr &op1,

    56                                  const AtomicComparator::Operator op,

    57                                  const Expression::Ptr &op2) : PairContainer(op1, op2),

    58                                                                m_operator(op)

    59 {

    60 }

    61 

    62 Item ValueComparison::evaluateSingleton(const DynamicContext::Ptr &context) const

    63 {

    64     const Item it1(m_operand1->evaluateSingleton(context));

    65     if(!it1)

    66         return Item();

    67 

    68     const Item it2(m_operand2->evaluateSingleton(context));

    69     if(!it2)

    70         return Item();

    71 

    72     return Boolean::fromValue(flexibleCompare(it1, it2, context));

    73 }

    74 

    75 Expression::Ptr ValueComparison::typeCheck(const StaticContext::Ptr &context,

    76                                            const SequenceType::Ptr &reqType)

    77 {

    78     const Expression::Ptr me(PairContainer::typeCheck(context, reqType));

    79     const ItemType::Ptr t1(m_operand1->staticType()->itemType());

    80     const ItemType::Ptr t2(m_operand2->staticType()->itemType());

    81     Q_ASSERT(t1);

    82     Q_ASSERT(t2);

    83 

    84     if(*CommonSequenceTypes::Empty == *t1 ||

    85        *CommonSequenceTypes::Empty == *t2)

    86     {

    87         return EmptySequence::create(this, context);

    88     }

    89     else

    90     {

    91         prepareComparison(fetchComparator(t1, t2, context));

    92 

    93         return me;

    94     }

    95 }

    96 

    97 Expression::Ptr ValueComparison::compress(const StaticContext::Ptr &context)

    98 {

    99     const Expression::Ptr me(PairContainer::compress(context));

   100 

   101     if(me != this)

   102         return me;

   103 

   104     if(isCaseInsensitiveCompare(m_operand1, m_operand2))

   105         useCaseInsensitiveComparator();

   106 

   107     return me;

   108 }

   109 

   110 bool ValueComparison::isCaseInsensitiveCompare(Expression::Ptr &op1, Expression::Ptr &op2)

   111 {

   112     Q_ASSERT(op1);

   113     Q_ASSERT(op2);

   114 

   115     const ID iD = op1->id();

   116 

   117     if((iD == IDLowerCaseFN || iD == IDUpperCaseFN) && iD == op2->id())

   118     {

   119         /* Both are either fn:lower-case() or fn:upper-case(). */

   120 

   121         /* Replace the calls to the functions with its operands. */

   122         op1 = op1->operands().first();

   123         op2 = op2->operands().first();

   124 

   125         return true;

   126     }

   127     else

   128         return false;

   129 }

   130 

   131 OptimizationPass::List ValueComparison::optimizationPasses() const

   132 {

   133     return OptimizationPasses::comparisonPasses;

   134 }

   135 

   136 SequenceType::List ValueComparison::expectedOperandTypes() const

   137 {

   138     SequenceType::List result;

   139     result.append(CommonSequenceTypes::ZeroOrOneAtomicType);

   140     result.append(CommonSequenceTypes::ZeroOrOneAtomicType);

   141     return result;

   142 }

   143 

   144 SequenceType::Ptr ValueComparison::staticType() const

   145 {

   146     if(m_operand1->staticType()->cardinality().allowsEmpty() ||

   147        m_operand2->staticType()->cardinality().allowsEmpty())

   148         return CommonSequenceTypes::ZeroOrOneBoolean;

   149     else

   150         return CommonSequenceTypes::ExactlyOneBoolean;

   151 }

   152 

   153 ExpressionVisitorResult::Ptr ValueComparison::accept(const ExpressionVisitor::Ptr &visitor) const

   154 {

   155     return visitor->visit(this);

   156 }

   157 

   158 Expression::ID ValueComparison::id() const

   159 {

   160     return IDValueComparison;

   161 }

   162 

   163 QT_END_NAMESPACE