source: trunk/src/xmlpatterns/expr/qcombinenodes.cpp@ 966

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#include "qcommonsequencetypes_p.h"
#include "qexceptiterator_p.h"
#include "qgenericsequencetype_p.h"
#include "qintersectiterator_p.h"
#include "qitemmappingiterator_p.h"
#include "qnodesort_p.h"
#include "qunioniterator_p.h"

#include "qcombinenodes_p.h"

QT_BEGIN_NAMESPACE

using namespace QPatternist;

CombineNodes::CombineNodes(const Expression::Ptr &operand1,
                           const Operator op,
                           const Expression::Ptr &operand2) : PairContainer(operand1, operand2),
                                                              m_operator(op)
{
    Q_ASSERT(op == Union    ||
             op == Except   ||
             op == Intersect);
}

Item::Iterator::Ptr CombineNodes::evaluateSequence(const DynamicContext::Ptr &context) const
{
    const Item::Iterator::Ptr op1(m_operand1->evaluateSequence(context));
    const Item::Iterator::Ptr op2(m_operand2->evaluateSequence(context));

    switch(m_operator)
    {
        case Intersect:
            return Item::Iterator::Ptr(new IntersectIterator(op1, op2));
        case Except:
            return Item::Iterator::Ptr(new ExceptIterator(op1, op2));
        default:
        {
            Q_ASSERT(m_operator == Union);
            return Item::Iterator::Ptr(new UnionIterator(op1, op2));
        }
    }
}

Item CombineNodes::evaluateSingleton(const DynamicContext::Ptr &context) const
{
    return evaluateSequence(context)->next();
}

Expression::Ptr CombineNodes::typeCheck(const StaticContext::Ptr &context,
                                        const SequenceType::Ptr &reqType)
{

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