source: trunk/src/xmlpatterns/functions/qcomparingaggregator.cpp@ 132

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/**
 * @file qcomparingaggregator.cpp
 * @short This file is included by qcomparingaggregator_p.h.
 * If you need includes in this file, put them in qcomparingaggregator_p.h, outside of the namespace.
 */

template <AtomicComparator::Operator oper, AtomicComparator::ComparisonResult result>
inline Item
ComparingAggregator<oper, result>::applyNumericPromotion(const Item &old,
                                                         const Item &nev,
                                                         const Item &newVal) const
{
    Q_ASSERT(old);
    Q_ASSERT(nev);
    Q_ASSERT(newVal);
    const ItemType::Ptr to(old.type());
    const ItemType::Ptr tn(nev.type());

    if(!(BuiltinTypes::numeric->xdtTypeMatches(to) && BuiltinTypes::numeric->xdtTypeMatches(tn)))
        return newVal; /* At least one of them isn't numeric. */
    else if(BuiltinTypes::xsDouble->xdtTypeMatches(to) || BuiltinTypes::xsDouble->xdtTypeMatches(tn))
        return toItem(Double::fromValue(newVal.as<Numeric>()->toDouble()));
    else if(BuiltinTypes::xsFloat->xdtTypeMatches(to) || BuiltinTypes::xsFloat->xdtTypeMatches(tn))
        return toItem(Float::fromValue(newVal.as<Numeric>()->toDouble()));
    else if(BuiltinTypes::xsInteger->xdtTypeMatches(to) &&
            BuiltinTypes::xsInteger->xdtTypeMatches(tn))
        return newVal; /* Both must be xs:integer. */
    else
        return toItem(Decimal::fromValue(newVal.as<Numeric>()->toDecimal()));
}

template <AtomicComparator::Operator oper, AtomicComparator::ComparisonResult result>
Item
ComparingAggregator<oper, result>::evaluateSingleton(const DynamicContext::Ptr &context) const
{
    const Item::Iterator::Ptr it(m_operands.first()->evaluateSequence(context));
    Item largest;

    while(true)
    {
        Item next(it->next());

        if(!next)
        {
            return largest;
        }

        AtomicComparator::Ptr comp(comparator());

        if(!comp)
        {
            ItemType::Ptr t1(next.type());
            Q_ASSERT(t1);

            if(BuiltinTypes::xsUntypedAtomic->xdtTypeMatches(t1))
            {
                next = cast(next, context);
                t1 = BuiltinTypes::xsDouble;
            }

            if(!largest)
            {
                largest = next;
                continue;
            }

            Q_ASSERT(largest);
            comp = fetchComparator(largest.type(), t1, context);
            Q_ASSERT(comp);
        }
        else if(!largest)
        {
            largest = next;
            continue;
        }

        if(comp->compare(next, operatorID(), largest) == result)
        {
            largest = applyNumericPromotion(largest, next, next);
            continue;
        }

        const ItemType::Ptr t(next.type());

        if(BuiltinTypes::xsDouble->xdtTypeMatches(t) &&
           next.as<Numeric>()->isNaN())
        {
            return CommonValues::DoubleNaN;
        }
        else if(BuiltinTypes::xsFloat->xdtTypeMatches(t) &&
                next.as<Numeric>()->isNaN())
        {
            if(BuiltinTypes::xsDouble->xdtTypeMatches(largest.type()))
                return CommonValues::DoubleNaN;

            /* If we have a xs:double somewhere, we must promote the NaN value to xs:double,
             * and we really should raise error on invalid value. */
            largest = it->next();

            while(largest)
            {
                const ItemType::Ptr tf(largest.type());