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44 #include "qcachingiterator_p.h"
48 using namespace QPatternist;
50 CachingIterator::CachingIterator(ItemSequenceCacheCell::Vector &cacheCells,
51 const VariableSlotID slot,
52 const DynamicContext::Ptr &context) : m_position(0),
55 m_cacheCells(cacheCells),
58 Q_ASSERT(m_varSlot > -1);
60 Q_ASSERT(m_cacheCells.at(m_varSlot).sourceIterator);
61 Q_ASSERT_X((m_cacheCells.at(m_varSlot).cachedItems.isEmpty() && m_cacheCells.at(m_varSlot).cacheState == ItemSequenceCacheCell::Empty) ||
62 m_cacheCells.at(m_varSlot).cacheState == ItemSequenceCacheCell::PartiallyPopulated,
64 "It makes no sense to construct a CachingIterator for a cache that is ItemSequenceCacheCell::Full.");
67 Item CachingIterator::next()
69 ItemSequenceCacheCell &cell = m_cacheCells[m_varSlot];
77 /* QAbstractXmlForwardIterator::position() starts at 1, while Qt's container classes
79 if(m_position - 1 < cell.cachedItems.count())
81 m_current = cell.cachedItems.at(m_position - 1);
86 cell.cacheState = ItemSequenceCacheCell::PartiallyPopulated;
88 /* We decrement here so we don't have to add a branch for this
89 * when using the source QAbstractXmlForwardIterator below. */
94 m_current = cell.sourceIterator->next();
98 cell.cachedItems.append(m_current);
99 Q_ASSERT(cell.cacheState == ItemSequenceCacheCell::PartiallyPopulated);
106 cell.cacheState = ItemSequenceCacheCell::Full;
111 Item CachingIterator::current() const
116 xsInteger CachingIterator::position() const
121 Item::Iterator::Ptr CachingIterator::copy() const
123 const ItemSequenceCacheCell &cell = m_cacheCells.at(m_varSlot);
124 if(cell.cacheState == ItemSequenceCacheCell::Full)
125 return makeListIterator(cell.cachedItems);
127 return Item::Iterator::Ptr(new CachingIterator(m_cacheCells, m_varSlot, m_context));