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// (C) Copyright Jeremy Siek 1999.
// Distributed under the Boost Software License, Version 1.0. (See
// accompanying file LICENSE_1_0.txt or copy at
// http://www.boost.org/LICENSE_1_0.txt)
#ifndef BOOST_TREE_STRUCTURE_HPP
#define BOOST_TREE_STRUCTURE_HPP
namespace boost {
template <class T>
struct tree_traits {
typedef typename T::node_descriptor node_descriptor;
typedef typename T::children_iterator children_iterator;
};
template <class Tree, class TreeVisitor>
void traverse_tree(typename tree_traits<Tree>::node_descriptor v,
Tree& t, TreeVisitor visitor)
{
visitor.preorder(v, t);
typename tree_traits<Tree>::children_iterator i, end;
boost::tie(i, end) = children(v, t);
if (i != end) {
traverse_tree(*i++, t, visitor);
visitor.inorder(v, t);
while (i != end)
traverse_tree(*i++, t, visitor);
} else
visitor.inorder(v, t);
visitor.postorder(v, t);
}
struct null_tree_visitor {
template <typename Node, typename Tree> void preorder(Node, Tree&) { }
template <typename Node, typename Tree> void inorder(Node, Tree&) { }
template <typename Node, typename Tree> void postorder(Node, Tree&) { }
};
} /* namespace boost */
#endif /* BOOST_TREE_STRUCTURE_HPP */
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