qandexpression.cpp

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#include "qboolean_p.h"
#include "qcommonsequencetypes_p.h"
#include "qcommonvalues_p.h"
#include "qliteral_p.h"

#include "qandexpression_p.h"

QT_BEGIN_NAMESPACE

using namespace QPatternist;

AndExpression::AndExpression(const Expression::Ptr &operand1,
                             const Expression::Ptr &operand2) : PairContainer(operand1, operand2)
{
}

bool AndExpression::evaluateEBV(const DynamicContext::Ptr &context) const
{
    return m_operand1->evaluateEBV(context) && m_operand2->evaluateEBV(context);
}

Expression::Ptr AndExpression::compress(const StaticContext::Ptr &context)
{
    const Expression::Ptr newMe(PairContainer::compress(context));

    if(newMe != this)
        return newMe;

    /* Both operands mustn't be evaluated in order to be able to compress. */
    if(m_operand1->isEvaluated() && !m_operand1->evaluateEBV(context->dynamicContext()))
        return wrapLiteral(CommonValues::BooleanFalse, context, this);
    else if(m_operand2->isEvaluated() && !m_operand2->evaluateEBV(context->dynamicContext()))
        return wrapLiteral(CommonValues::BooleanFalse, context, this);
    else
        return Expression::Ptr(this);
}

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

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

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

QT_END_NAMESPACE