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39
40#include "qitem_p.h"
41
42#include "qexceptiterator_p.h"
43
44QT_BEGIN_NAMESPACE
45
46using namespace QPatternist;
47
48ExceptIterator::ExceptIterator(const Item::Iterator::Ptr &it1,
49 const Item::Iterator::Ptr &it2) : m_it1(it1)
50 , m_it2(it2)
51 , m_position(0)
52 , m_node1(m_it1->next())
53 , m_node2(m_it2->next())
54{
55 Q_ASSERT(m_it1);
56 Q_ASSERT(m_it2);
57}
58
59Item ExceptIterator::fromFirstOperand()
60{
61 ++m_position;
62 m_current = m_node1;
63 m_node1 = m_it1->next();
64
65 return m_current;
66}
67
68Item ExceptIterator::next()
69{
70 while(true)
71 {
72 if(!m_node1)
73 {
74 m_position = -1;
75 m_current = Item();
76 return Item();
77 }
78 else if(!m_node2)
79 return fromFirstOperand();
80
81 if(m_node1.asNode().model() != m_node2.asNode().model())
82 return fromFirstOperand();
83
84 switch(m_node1.asNode().compareOrder(other: m_node2.asNode()))
85 {
86 case QXmlNodeModelIndex::Precedes:
87 return fromFirstOperand();
88 case QXmlNodeModelIndex::Follows:
89 {
90 m_node2 = m_it2->next();
91 if(m_node2)
92 continue;
93 else
94 return fromFirstOperand();
95 }
96 default:
97 {
98 m_node1 = m_it1->next();
99 m_node2 = m_it2->next();
100 }
101 }
102 }
103}
104
105Item ExceptIterator::current() const
106{
107 return m_current;
108}
109
110xsInteger ExceptIterator::position() const
111{
112 return m_position;
113}
114
115Item::Iterator::Ptr ExceptIterator::copy() const
116{
117 return Item::Iterator::Ptr(new ExceptIterator(m_it1->copy(), m_it2->copy()));
118}
119
120QT_END_NAMESPACE
121

source code of qtxmlpatterns/src/xmlpatterns/iterators/qexceptiterator.cpp