source: trunk/src/xmlpatterns/expr/qgenericpredicate.cpp@ 243

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#include "qabstractfloat_p.h"
#include "qboolean_p.h"
#include "qbuiltintypes_p.h"
#include "qcommonsequencetypes_p.h"
#include "qemptysequence_p.h"
#include "qfirstitempredicate_p.h"
#include "qgenericsequencetype_p.h"
#include "qitemmappingiterator_p.h"
#include "qliteral_p.h"
#include "qpatternistlocale_p.h"
#include "qtruthpredicate_p.h"

#include "qgenericpredicate_p.h"

QT_BEGIN_NAMESPACE

using namespace QPatternist;

GenericPredicate::GenericPredicate(const Expression::Ptr &sourceExpression,
                                   const Expression::Ptr &predicate) : PairContainer(sourceExpression,
                                                                                     predicate)
{
}

Expression::Ptr GenericPredicate::create(const Expression::Ptr &sourceExpression,
                                         const Expression::Ptr &predicateExpression,
                                         const StaticContext::Ptr &context,
                                         const QSourceLocation &location)
{
    Q_ASSERT(sourceExpression);
    Q_ASSERT(predicateExpression);
    Q_ASSERT(context);
    const ItemType::Ptr type(predicateExpression->staticType()->itemType());

    if(predicateExpression->is(IDIntegerValue) &&
       predicateExpression->as<Literal>()->item().as<Numeric>()->toInteger() == 1)
    { /* Handle [1] */
        return createFirstItem(sourceExpression);
    }
    else if(BuiltinTypes::numeric->xdtTypeMatches(type))
    { /* A numeric predicate, other than [1]. */
        /* TODO at somepoint we'll return a specialized expr here, NumericPredicate or so.
         * Dependency analysis is a bit tricky, since the contained expression can depend on
         * some loop component. */
        return Expression::Ptr(new GenericPredicate(sourceExpression, predicateExpression));
    }
    else if(*CommonSequenceTypes::Empty == *type)
    {
        return EmptySequence::create(predicateExpression.data(), context);
    }
    else if(*BuiltinTypes::item == *type ||
            *BuiltinTypes::xsAnyAtomicType == *type)
    {
        /* The type couldn't be narrowed at compile time, so we use
         * a generic predicate. This check is before the CommonSequenceTypes::EBV check,
         * because the latter matches these types as well. */
        return Expression::Ptr(new GenericPredicate(sourceExpression, predicateExpression));
    }
    else if(CommonSequenceTypes::EBV->itemType()->xdtTypeMatches(type))
    {
        return Expression::Ptr(new TruthPredicate(sourceExpression, predicateExpression));
    }
    else
    {
        context->error(QtXmlPatterns::tr("A value of type %1 cannot be a "
                                         "predicate. A predicate must have "
                                         "either a numeric type or an "
                                         "Effective Boolean Value type.")
                       .arg(formatType(context->namePool(),
                                       sourceExpression->staticType())),
                       ReportContext::FORG0006, location);
        return Expression::Ptr(); /* Silence compiler warning. */
    }
}

Expression::Ptr GenericPredicate::createFirstItem(const Expression::Ptr &sourceExpression)

{
    return Expression::Ptr(new FirstItemPredicate(sourceExpression));
}

Item GenericPredicate::mapToItem(const Item &item,
                                 const DynamicContext::Ptr &context) const
{
    const Item::Iterator::Ptr it(m_operand2->evaluateSequence(context));
    const Item pcateItem(it->next());