qLess< Item::List > Class Template Reference

Functor used by Qt's qSort() and qStableSort(). Used for FLWOR's order by expression. More...

Public Functions
bool	operator() (const Item &item1, const Item &item2) const
	qLess (const OrderBy::OrderSpec::Vector &orderspecs, const DynamicContext::Ptr &context)

Static Private Functions
static bool	isNaN (const Item &i)

Properties
const DynamicContext::Ptr &	m_context
const OrderBy::OrderSpec::Vector &	m_orderSpecs

Detailed Description

template<>
class qLess< Item::List >

Functor used by Qt's qSort() and qStableSort(). Used for FLWOR's order by expression.

This must be in the global namespace, since it is specializing qLess(), which is in the global namespace. Hence it can't be in QPatternist.

Definition at line 85 of file qorderby.cpp.

Constructors and Destructors

qLess()

qLess< Item::List >::qLess ( const OrderBy::OrderSpec::Vector &  orderspecs, const DynamicContext::Ptr &  context  )

inline

Definition at line 96 of file qorderby.cpp.

                                                   : m_orderSpecs(orderspecs)
                                                     , m_context(context)
    {
        Q_ASSERT(!m_orderSpecs.isEmpty());
        Q_ASSERT(context);
    }

Functions

isNaN()

static bool qLess< Item::List >::isNaN ( const Item &  i )

inlinestaticprivate

Definition at line 89 of file qorderby.cpp.

    {
        return BuiltinTypes::xsDouble->xdtTypeMatches(i.type()) &&
               i.as<Numeric>()->isNaN();
    }

operator()()

bool qLess< Item::List >::operator() ( const Item &  item1, const Item &  item2  ) const

inline

Definition at line 104 of file qorderby.cpp.

    {
        const SortTuple *const s1 = item1.as<SortTuple>();
        const SortTuple *const s2 = item2.as<SortTuple>();

        const Item::Vector &sortKeys1 = s1->sortKeys();
        const Item::Vector &sortKeys2 = s2->sortKeys();
        const int len = sortKeys1.count();
        Q_ASSERT(sortKeys1.count() == sortKeys2.count());

        for(int i = 0; i < len; ++i)
        {
            const Item &i1 = sortKeys1.at(i);
            const Item &i2 = sortKeys2.at(i);
            const OrderBy::OrderSpec &orderSpec = m_orderSpecs.at(i);

            if(!i1)
            {
                if(i2 && !isNaN(i2))
                {
                    /* We got ((), item()). */
                    return orderSpec.orderingEmptySequence == StaticContext::Least ? orderSpec.direction == OrderBy::OrderSpec::Ascending
                                                                                   : orderSpec.direction != OrderBy::OrderSpec::Ascending;
                }
                else
                    return false;
            }

            if(!i2)
            {
                if(i1 && !isNaN(i1))
                    /* We got (item(), ()). */
                    return orderSpec.orderingEmptySequence == StaticContext::Greatest ? orderSpec.direction == OrderBy::OrderSpec::Ascending
                                                                                      : orderSpec.direction != OrderBy::OrderSpec::Ascending;
                else
                    return false;
            }

            Q_ASSERT(orderSpec.direction == OrderBy::OrderSpec::Ascending ||
                     orderSpec.direction == OrderBy::OrderSpec::Descending);
            const AtomicComparator::ComparisonResult result = orderSpec.detailedFlexibleCompare(i1, i2, m_context);

            switch(result)
            {
                case AtomicComparator::LessThan:
                    return orderSpec.direction == OrderBy::OrderSpec::Ascending;
                case AtomicComparator::GreaterThan:
                    return orderSpec.direction != OrderBy::OrderSpec::Ascending;
                case AtomicComparator::Equal:
                    continue;
                case AtomicComparator::Incomparable:
                    Q_ASSERT_X(false, Q_FUNC_INFO, "This code path assume values are always comparable.");
            }
        }

        return false;
    }

Properties

m_context

const DynamicContext::Ptr& qLess< Item::List >::m_context

private

Definition at line 165 of file qorderby.cpp.

m_orderSpecs

const OrderBy::OrderSpec::Vector& qLess< Item::List >::m_orderSpecs

private

Definition at line 164 of file qorderby.cpp.

---

The documentation for this class was generated from the following file:

• /src/xmlpatterns/expr/qorderby.cpp