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#include "qcommonsequencetypes_p.h"

#include "qgenericsequencetype_p.h"

#include "qoptimizationpasses_p.h"

#include "qifthenclause_p.h"

QT_BEGIN_NAMESPACE

using namespace QPatternist;

IfThenClause::IfThenClause(const Expression::Ptr &test,

                           const Expression::Ptr &then,

                           const Expression::Ptr &el) : TripleContainer(test, then, el)

{

}

Item::Iterator::Ptr IfThenClause::evaluateSequence(const DynamicContext::Ptr &context) const

{

    return m_operand1->evaluateEBV(context)

            ? m_operand2->evaluateSequence(context)

            : m_operand3->evaluateSequence(context);

}

Item IfThenClause::evaluateSingleton(const DynamicContext::Ptr &context) const

{

    return m_operand1->evaluateEBV(context)

            ? m_operand2->evaluateSingleton(context)

            : m_operand3->evaluateSingleton(context);

}

bool IfThenClause::evaluateEBV(const DynamicContext::Ptr &context) const

{

    return m_operand1->evaluateEBV(context)

            ? m_operand2->evaluateEBV(context)

            : m_operand3->evaluateEBV(context);

}

void IfThenClause::evaluateToSequenceReceiver(const DynamicContext::Ptr &context) const

{

    if(m_operand1->evaluateEBV(context))

        m_operand2->evaluateToSequenceReceiver(context);

    else

        m_operand3->evaluateToSequenceReceiver(context);

}

Expression::Ptr IfThenClause::compress(const StaticContext::Ptr &context)

{

    const Expression::Ptr me(TripleContainer::compress(context));

    if(me != this)

        return me;

    /* All operands mustn't be evaluated in order for const folding to

     * be possible. Let's see how far we get. */

    if(m_operand1->isEvaluated())

    {

        if(m_operand1->evaluateEBV(context->dynamicContext()))

            return m_operand2;

        else

            return m_operand3;

    }

    else

        return me;

}

QList<QExplicitlySharedDataPointer<OptimizationPass> > IfThenClause::optimizationPasses() const

{

    return OptimizationPasses::ifThenPasses;

}

SequenceType::List IfThenClause::expectedOperandTypes() const

{

    SequenceType::List result;

    result.append(CommonSequenceTypes::EBV);

    result.append(CommonSequenceTypes::ZeroOrMoreItems);

    result.append(CommonSequenceTypes::ZeroOrMoreItems);

    return result;

}

SequenceType::Ptr IfThenClause::staticType() const

{

    const SequenceType::Ptr t1(m_operand2->staticType());

    const SequenceType::Ptr t2(m_operand3->staticType());

    return makeGenericSequenceType(t1->itemType() | t2->itemType(),

                                   t1->cardinality() | t2->cardinality());

}

ExpressionVisitorResult::Ptr IfThenClause::accept(const ExpressionVisitor::Ptr &visitor) const

{

    return visitor->visit(this);

}

Expression::ID IfThenClause::id() const

{

    return IDIfThenClause;

}

/*

Expression::Properties IfThenClause::properties() const

{

    return   m_operand1->properties()

           | m_operand2->properties()

           | m_operand3->properties()

           & (  Expression::RequiresFocus

              | Expression::IsEvaluated

              | Expression::DisableElimination);

}

*/

QT_END_NAMESPACE