[Jorgen Grahn] > Neither C++ nor Python has tree structures in their standard > libraries. I assume that's because there is no single interface that > is proven to suit everybody's needs.
It is already easy writing "tree constants" using recursive tuples or lists. To process simple trees in Python, I usually subclass some Node type from list, and write the traversal methods that suit the application. The sub-classing already allow for indexing sub-nodes by "self[index]", and iterating over all by "for subnode in self:", etc. In my experience, it all goes pretty easily, while staying simple. However, things related to balancing, finding paths between nodes, or searching for patterns, etc. may require more work. There are surely a flurry of tree algorithms out there. What are the actual needs you have, and would want to see covered by a library? -- François Pinard http://pinard.progiciels-bpi.ca -- http://mail.python.org/mailman/listinfo/python-list
