source: trunk/src/xmlpatterns/expr/qquantifiedexpression.cpp@ 612

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#include "qcommonsequencetypes_p.h"
#include "qgenericsequencetype_p.h"
#include "qitemmappingiterator_p.h"

#include "qquantifiedexpression_p.h"

QT_BEGIN_NAMESPACE

using namespace QPatternist;

QuantifiedExpression::QuantifiedExpression(const VariableSlotID varSlot,
                                           const Operator quantifier,
                                           const Expression::Ptr &inClause,
                                           const Expression::Ptr &testExpression)
                                           : PairContainer(inClause, testExpression),
                                             m_varSlot(varSlot),
                                             m_quantifier(quantifier)
{
    Q_ASSERT(quantifier == Some || quantifier == Every);
}

Item QuantifiedExpression::mapToItem(const Item &item,
                                          const DynamicContext::Ptr &context) const
{
    context->setRangeVariable(m_varSlot, item);
    return item;
}

bool QuantifiedExpression::evaluateEBV(const DynamicContext::Ptr &context) const
{
    const Item::Iterator::Ptr it(makeItemMappingIterator<Item>(ConstPtr(this),
                                                               m_operand1->evaluateSequence(context),
                                                               context));

    Item item(it->next());

    if(m_quantifier == Some)
    {
        while(item)
        {
            if(m_operand2->evaluateEBV(context))
                return true;
            else
                item = it->next();
        };

        return false;
    }
    else
    {
        Q_ASSERT(m_quantifier == Every);

        while(item)
        {
            if(m_operand2->evaluateEBV(context))
                item = it->next();
            else
                return false;
        }

        return true;
    }
}

QString QuantifiedExpression::displayName(const Operator quantifier)
{
    if(quantifier == Some)
        return QLatin1String("some");
    else
    {
        Q_ASSERT(quantifier == Every);
        return QLatin1String("every");
    }
}

SequenceType::Ptr QuantifiedExpression::staticType() const
{
    return CommonSequenceTypes::ExactlyOneBoolean;
}

SequenceType::List QuantifiedExpression::expectedOperandTypes() const
{
    SequenceType::List result;
    result.append(CommonSequenceTypes::ZeroOrMoreItems);
    result.append(CommonSequenceTypes::EBV);
    return result;
}

QuantifiedExpression::Operator QuantifiedExpression::operatorID() const
{
    return m_quantifier;
}

ExpressionVisitorResult::Ptr QuantifiedExpression::accept(const ExpressionVisitor::Ptr &visitor) const
{
    return visitor->visit(this);
}

QT_END_NAMESPACE