tree_traits.hpp
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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
#include <boost/tuple/tuple.hpp> //For boost::tie()
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 */