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19 
20 #ifndef INCLUDED_SVX_SOURCE_INC_TREEVISITOR_HXX
21 #define INCLUDED_SVX_SOURCE_INC_TREEVISITOR_HXX
22 
23 #include <stack>
24 
25 template< class ELEMENT, class NODEINFO, class PROCESSOR >
26 class TreeVisitor
27 {
28 public:
TreeVisitor(NODEINFO _nodeInfo)29     TreeVisitor( NODEINFO _nodeInfo )
30         :m_visitedRoot( false )
31         ,m_root()
32         ,m_current()
33         ,m_nodeInfo( _nodeInfo )
34     {
35     }
36 
process(const ELEMENT & _root,PROCESSOR & _processor)37     void    process( const ELEMENT& _root, PROCESSOR& _processor )
38     {
39         m_root = _root;
40         m_visitedRoot = false;
41 
42         while ( do_step() )
43             _processor.process( m_current );
44     }
45 
46 private:
47     bool    do_step();
48 
49 private:
50     bool            m_visitedRoot;
51     ELEMENT         m_root;
52     ELEMENT         m_current;
53     const NODEINFO  m_nodeInfo;
54 
55     ::std::stack< size_t >  m_pathToCurrent;
56     ::std::stack< ELEMENT > m_currentAncestors;
57 };
58 
59 template< class ELEMENT, class NODEINFO, class PROCESSOR >
do_step()60 bool TreeVisitor< ELEMENT, NODEINFO, PROCESSOR >::do_step()
61 {
62     if ( !m_visitedRoot )
63     {
64         m_current = m_root;
65         m_visitedRoot = true;
66         return true;
67     }
68 
69     // can we step down from the current node?
70     size_t childCount = m_nodeInfo.childCount( m_current );
71     if ( childCount )
72     {
73         m_currentAncestors.push( m_current );
74         m_current = m_nodeInfo.getChild( m_current, 0 );
75         m_pathToCurrent.push( 0 );
76         return true;
77     }
78 
79     // is there a right sibling of the current node?
80     while ( !m_pathToCurrent.empty() )
81     {
82         const ELEMENT& currentParent = m_currentAncestors.top();
83         childCount = m_nodeInfo.childCount( currentParent );
84 
85         size_t currentChildPos = m_pathToCurrent.top();
86         if ( ++currentChildPos < childCount )
87         {
88             // yes there is
89             m_pathToCurrent.top() = currentChildPos;
90             m_current = m_nodeInfo.getChild( currentParent, currentChildPos );
91             return true;
92         }
93 
94         // no there isn't => step up
95         m_currentAncestors.pop();
96         m_pathToCurrent.pop();
97     }
98 
99     return false;
100 }
101 
102 #endif // INCLUDED_SVX_SOURCE_INC_TREEVISITOR_HXX
103 
104 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */
105